WorldWideScience

Sample records for horizontal distribution patterns

  1. Localisation of nursery areas based on comparative analyses of the horizontal and vertical distribution patterns of juvenile Baltic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Nielsen, J. Rasmus; Lundgren, Bo; Kristensen, Kasper

    2013-01-01

    and acoustic research surveys. Horizontal distribution maps for the 2001–2010 cohorts of juvenile cod are further generated by applying a statistical log-Gaussian Cox process model to the standard trawl survey data. The analyses indicate size-dependent horizontal and distinct vertical and diurnal distribution......Knowledge of the spatial distribution of juvenile cod is essential for obtaining precise recruitment data to conduct sustainable management of the eastern and western Baltic cod stocks. In this study, the horizontal and vertical distribution and density patterns of settled juvenile 0- and 1-group...... Baltic cod are determined, and their nursery areas are localised according to the environmental factors affecting them. Comparative statistical analyses of biological, hydrographic and hydroacoustic data are carried out based on standard ICES demersal trawl surveys and special integrated trawl...

  2. Localisation of nursery areas based on comparative analyses of the horizontal and vertical distribution patterns of juvenile Baltic cod (Gadus morhua.

    Directory of Open Access Journals (Sweden)

    J Rasmus Nielsen

    Full Text Available Knowledge of the spatial distribution of juvenile cod is essential for obtaining precise recruitment data to conduct sustainable management of the eastern and western Baltic cod stocks. In this study, the horizontal and vertical distribution and density patterns of settled juvenile 0- and 1-group Baltic cod are determined, and their nursery areas are localised according to the environmental factors affecting them. Comparative statistical analyses of biological, hydrographic and hydroacoustic data are carried out based on standard ICES demersal trawl surveys and special integrated trawl and acoustic research surveys. Horizontal distribution maps for the 2001-2010 cohorts of juvenile cod are further generated by applying a statistical log-Gaussian Cox process model to the standard trawl survey data. The analyses indicate size-dependent horizontal and distinct vertical and diurnal distribution patterns related to the seabed topography, water layer depth, and the presence of hydrographic frontal zones (pycnoclines as well as intraspecific patterns in relation to the presence of adult cod. The extent of the nursery areas also depends on the cod year class strength. Juvenile cod (≥3 cm are present in all areas of the central Baltic Sea (CBS, showing broad dispersal. However, their highest density in the Baltic Basins is found at localities with a 40-70 m bottom depth in waters with oxygen concentrations above 2 ml O₂.l⁻¹ and temperatures above 5°C. The smallest juveniles are also found in deep sea localities down to a 100 m depth and at oxygen concentrations between 2-4 ml O₂.l⁻¹. The vertical, diurnally stratified and repeated trawling and hydroacoustic target strength-depth distributions obtained from the special surveys show juvenile cod concentrations in frontal zone water layers (pycnocline. However, the analyses indicate that in the CBS, juvenile cod of all sizes do not appear to aggregate in dense schooling patterns, which differs

  3. Localisation of nursery areas based on comparative analyses of the horizontal and vertical distribution patterns of juvenile Baltic cod (Gadus morhua).

    Science.gov (United States)

    Nielsen, J Rasmus; Lundgren, Bo; Kristensen, Kasper; Bastardie, Francois

    2013-01-01

    Knowledge of the spatial distribution of juvenile cod is essential for obtaining precise recruitment data to conduct sustainable management of the eastern and western Baltic cod stocks. In this study, the horizontal and vertical distribution and density patterns of settled juvenile 0- and 1-group Baltic cod are determined, and their nursery areas are localised according to the environmental factors affecting them. Comparative statistical analyses of biological, hydrographic and hydroacoustic data are carried out based on standard ICES demersal trawl surveys and special integrated trawl and acoustic research surveys. Horizontal distribution maps for the 2001-2010 cohorts of juvenile cod are further generated by applying a statistical log-Gaussian Cox process model to the standard trawl survey data. The analyses indicate size-dependent horizontal and distinct vertical and diurnal distribution patterns related to the seabed topography, water layer depth, and the presence of hydrographic frontal zones (pycnoclines) as well as intraspecific patterns in relation to the presence of adult cod. The extent of the nursery areas also depends on the cod year class strength. Juvenile cod (≥3 cm) are present in all areas of the central Baltic Sea (CBS), showing broad dispersal. However, their highest density in the Baltic Basins is found at localities with a 40-70 m bottom depth in waters with oxygen concentrations above 2 ml O₂.l⁻¹ and temperatures above 5°C. The smallest juveniles are also found in deep sea localities down to a 100 m depth and at oxygen concentrations between 2-4 ml O₂.l⁻¹. The vertical, diurnally stratified and repeated trawling and hydroacoustic target strength-depth distributions obtained from the special surveys show juvenile cod concentrations in frontal zone water layers (pycnocline). However, the analyses indicate that in the CBS, juvenile cod of all sizes do not appear to aggregate in dense schooling patterns, which differs from what has

  4. Decapod crustacean larval communities in the Balearic Sea (western Mediterranean): Seasonal composition, horizontal and vertical distribution patterns

    Science.gov (United States)

    Torres, Asvin P.; Dos Santos, Antonina; Balbín, Rosa; Alemany, Francisco; Massutí, Enric; Reglero, Patricia

    2014-10-01

    Decapod crustaceans are the main target species of deep water bottom trawl fisheries in the Balearic Sea but little is known about their larval stages. This work focuses on the species composition of the decapod larval community, describing the main spatio-temporal assemblages and assessing their vertical distribution. Mesozooplankton sampling was carried out using depth-stratified sampling devices at two stations located over the shelf break and the mid slope, in the north-western and southern Mallorca in late autumn 2009 and summer 2010. Differences among decapod larvae communities, in terms of composition, adult's habitat such as pelagic or benthic, and distribution patterns were observed between seasons, areas and station. Results showed that for both seasons most species and developmental stages aggregated within the upper water column (above 75 m depth) and showed higher biodiversity in summer compared to late autumn. Most abundant species were pelagic prawns (e.g., Sergestidae) occurring in both seasons and areas. The larval assemblages' distributions were different between seasonal hydrographic scenarios and during situations of stratified and non-stratified water column. The vertical distribution patterns of different larval developmental stages in respect to the adult's habitat were analyzed in relation to environmental variables. Fluorescence had the highest explanatory power. Four clearly different vertical patterns were identified: two corresponding to late autumn, which were common for all the main larval groups and other two in summer, one corresponding to larvae of coastal benthic and the second to pelagic species larvae.

  5. An analysis of the horizontal burrow morphology of the oriental mole cricket (Gryllotalpa orientalis) and the distribution pattern of surface vegetation

    National Research Council Canada - National Science Library

    Endo, C

    2008-01-01

    .... The burrowing patterns of the oriental mole cricket (Gryllotalpa orientalis Brumeister, 1838) (Orthoptera: Gryllotalpidae) were investigated based on analyses of the relation between burrow morphology and plant distribution...

  6. comparative evaluation of pressure distribution between horizontal ...

    African Journals Online (AJOL)

    user

    Green and source function were used to evaluate the performance of horizontal well and vertical well, eventually, compared based dimensionless pressures and pressure derivatives computed by varying the reservoir geometry. Results presented as type curves show that the rate of decline of the pressure derivative curve is.

  7. Comparative evaluation of pressure distribution between horizontal ...

    African Journals Online (AJOL)

    Green and source function were used to evaluate the performance of horizontal well and vertical well, eventually, compared based dimensionless pressures and pressure derivatives computed by varying the reservoir geometry. Results presented as type curves show that the rate of decline of the pressure derivative curve is ...

  8. Determination of horizontal and vertical distribution of tree species in ...

    African Journals Online (AJOL)

    Determination of horizontal and vertical distribution of tree species in Turkey via Shuttle Radar Topography Mission (SRTM) satellite data and geographic information system: the case of Crimean pine ( Pinus nigra )

  9. FLOW DISTRIBUTION IN A SOLAR COLLECTOR PANEL WITH HORIZONTAL FINS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Shah, Louise Jivan; Furbo, Simon

    2005-01-01

    The objective of this work is to theoretically and experimentally investigate the flow and temperature distribution in a solar collector panel with an absorber consisting of horizontal fins. Fluid flow and heat transfer in the collector panel are studied by means of computational fluid dynamics...... (CFD) calculations. Further, experimental investigations of a 12.5 m² solar collector panel with 16 parallel connected horizontal fins are carried out. The flow distribution through the absorber is evaluated by means of temperature measurements on the backside of the absorber tubes. The measured...

  10. Coolant rate distribution in horizontal steam generator under natural circulation

    Energy Technology Data Exchange (ETDEWEB)

    Blagovechtchenski, A.; Leontieva, V.; Mitrioukhin, A. [St. Petersburg State Technical Univ. (Russian Federation)

    1997-12-31

    In the presentation the major factors determining the conditions of NCC (Natural Coolant Circulation) in the primary circuit and in particular conditions of coolant rate distribution on the horizontal tubes of PGV-1000 in NPP with VVER-1000 under NCC are considered. 5 refs.

  11. Determination of horizontal and vertical distribution of tree species in ...

    African Journals Online (AJOL)

    Yomi

    2012-01-24

    Jan 24, 2012 ... using a digital elevation model obtained from Shuttle Radar Topography Mission (SRTM) satellite data and 1/100,000 scale Forest Information System database, horizontal and vertical distribution of Pinus nigra (Crimean Pine), which is geographically the largest spread needled tree species in Turkey, (to.

  12. The patterning of retinal horizontal cells: normalizing the regularity index enhances the detection of genomic linkage

    Directory of Open Access Journals (Sweden)

    Patrick W. Keeley

    2014-10-01

    Full Text Available Retinal neurons are often arranged as non-random distributions called mosaics, as their somata minimize proximity to neighboring cells of the same type. The horizontal cells serve as an example of such a mosaic, but little is known about the developmental mechanisms that underlie their patterning. To identify genes involved in this process, we have used three different spatial statistics to assess the patterning of the horizontal cell mosaic across a panel of genetically distinct recombinant inbred strains. To avoid the confounding effect cell density, which varies two-fold across these different strains, we computed the real/random regularity ratio, expressing the regularity of a mosaic relative to a randomly distributed simulation of similarly sized cells. To test whether this latter statistic better reflects the variation in biological processes that contribute to horizontal cell spacing, we subsequently compared the genetic linkage for each of these two traits, the regularity index and the real/random regularity ratio, each computed from the distribution of nearest neighbor (NN distances and from the Voronoi domain (VD areas. Finally, we compared each of these analyses with another index of patterning, the packing factor. Variation in the regularity indexes, as well as their real/random regularity ratios, and the packing factor, mapped quantitative trait loci (QTL to the distal ends of Chromosomes 1 and 14. For the NN and VD analyses, we found that the degree of linkage was greater when using the real/random regularity ratio rather than the respective regularity index. Using informatic resources, we narrow the list of prospective genes positioned at these two intervals to a small collection of six genes that warrant further investigation to determine their potential role in shaping the patterning of the horizontal cell mosaic.

  13. Horizonte

    OpenAIRE

    BABIANO MARTÍNEZ, CARLOS JOSÉ

    2015-01-01

    Este proyecto intenta ahondar en la idea de horizonte tratado desde la filosofía japonesa y de su nexo con el mundo occidental. De la necesidad latente de una restructuración de la educación para convertirla en una educación estética capaz de permitir a los individuos completarse plenamente como personas. A través de las enseñanzas orientales del zen, del haiku, de filósofos como Tanizaki, y sus ideas sobre la sombra y la sugerencia, frente a Kierkegaard o Schiller en el lado occidental y sus...

  14. Itaipu reservoir limnology: eutrophication degree and the horizontal distribution of its limnological variables

    Directory of Open Access Journals (Sweden)

    RA. Ribeiro Filho

    Full Text Available Reservoirs are manmade habitats, intermediate between rivers and lakes, presenting distinct hydrological and morphometric characteristics, with differential mean water residence time. They also present proper vertical and horizontal organisations, and their evolution depends on several variables acting on different special and temporal scales. The water quality evolution of the Itaipu Reservoir was evaluated through the analysis of the physical, chemical and biological variables, and by the application of Trophic State Indices. We concluded that the limnological variables present a horizontal pattern of variation highly dependent upon the hydrological regime. The turbidity and total suspended solids presented the same distribution pattern in the reservoir zones. The fluvial zone had the highest concentrations of nutrients, suspended solids and turbidity. The results of the Trophic State Indices indicate a mesotrophic level for the fluvial and transition zones, and an oligotrophic one for the lacustrine zone.

  15. Modeling residence-time distribution in horizontal screw hydrolysis reactors

    Energy Technology Data Exchange (ETDEWEB)

    Sievers, David A.; Stickel, Jonathan J.

    2018-01-01

    The dilute-acid thermochemical hydrolysis step used in the production of liquid fuels from lignocellulosic biomass requires precise residence-time control to achieve high monomeric sugar yields. Difficulty has been encountered reproducing residence times and yields when small batch reaction conditions are scaled up to larger pilot-scale horizontal auger-tube type continuous reactors. A commonly used naive model estimated residence times of 6.2-16.7 min, but measured mean times were actually 1.4-2.2 the estimates. This study investigated how reactor residence-time distribution (RTD) is affected by reactor characteristics and operational conditions, and developed a method to accurately predict the RTD based on key parameters. Screw speed, reactor physical dimensions, throughput rate, and process material density were identified as major factors affecting both the mean and standard deviation of RTDs. The general shape of RTDs was consistent with a constant value determined for skewness. The Peclet number quantified reactor plug-flow performance, which ranged between 20 and 357.

  16. Insights into horizontal acquisition patterns of dormancy and ...

    Indian Academy of Sciences (India)

    2016-07-22

    Jul 22, 2016 ... Horizontal Gene Transfer (HGT) events, initially thought to be rare in Mycobacterium tuberculosis, have recently been shown to be involved in the acquisition of virulence operons in M. tuberculosis. We have developed a new partitioning framework based HGT prediction algorithm, called Grid3M, and ...

  17. Insights into horizontal acquisition patterns of dormancy and ...

    Indian Academy of Sciences (India)

    Horizontal Gene Transfer (HGT) events, initially thought to be rare in Mycobacterium tuberculosis, have recentlybeen shown to be involved in the acquisition of virulence operons in M. tuberculosis. We have developed a newpartitioning framework based HGT prediction algorithm, called Grid3M, and applied the same for the ...

  18. Driving Risk Affected Areas and Distribution Function of Sharp Horizontal Curves of Expressway

    Directory of Open Access Journals (Sweden)

    Xiao-fei Wang

    2015-01-01

    Full Text Available The average death and injury intensity on sharp horizontal curves (SHCs are much higher than those of straight sections of the expressway in China. In this paper, the statistics of crashes from 2008 to 2012 on 2200 km expressways in Guangdong province are collected, and the relationships between the radius of plane curves and the crash rate are analyzed. After that, the curved expressway section with radius equal to or less than 1000 m is defined as SHCs. According to the results of the test of the operating speed, the heart rate change of drivers, and the vehicle acceleration, the distribution patterns of driving risks on the certain SHCs were theoretically analyzed. Hence, the driving risk affected areas on adjacent line units of SHCs are determined as 200 m sections before entering or after exiting the SHCs. Combining with surveyed data, the spatial distribution of crashes on SHCs is analyzed, and the driving risk distribution function of SHCs in expressway is finally deduced. The result of this research provides a theoretical basis to enhance expressway safety management and to improve the driving safety on SHCs.

  19. Receiving beam patterns in the horizontal plane of a harbor porpoise (Phocoena phocoena)

    NARCIS (Netherlands)

    Kastelein, R.A.; Janssen, M.; Verboom, W.C.; Haan, D. de

    2005-01-01

    Receiving beam patterns of a harbor porpoise were measured in the horizontal plane, using narrow-band frequency modulated signals with center frequencies of 16, 64, and 100 kHz. Total signal duration was 1000 ms, including a 200 ms rise time and 300 ms fall time. The harbor porpoise was trained to

  20. Differences in vertical and horizontal distribution of fish larvae and zooplankton, related to hydrography

    DEFF Research Database (Denmark)

    Höffle, Hannes; Nash, Richard D.M.; Falkenhaug, Tone

    2013-01-01

    Planktonic fish larvae have little influence on their horizontal distribution, while they are able to control their vertical position in the water column. While prey and light are among the factors with an apparent influence on the vertical distribution, the effects of other factors are less clea...

  1. Aerodynamic design of horizontal axis wind turbine with innovative local linearization of chord and twist distributions

    DEFF Research Database (Denmark)

    Tahani, Mojtaba; Kavari, Ghazale; Masdari, Mehran

    2017-01-01

    This study is aimed to aerodynamically design a 1 mega-Watt horizontal axis wind turbine in order to obtain the maximum power coefficient by linearizing the chord and twist distributions. A new linearization method has been used for chord and twist distributions by crossing tangent line through...

  2. Flow Pattern Identification of Horizontal Two-Phase Refrigerant Flow Using Neural Networks

    Science.gov (United States)

    2015-12-31

    making classification difficult. Consequently, Table 5 shows neural net - work classification results for nine flow patterns. The number of runs...AFRL-RQ-WP-TP-2016-0079 FLOW PATTERN IDENTIFICATION OF HORIZONTAL TWO-PHASE REFRIGERANT FLOW USING NEURAL NETWORKS (POSTPRINT) Abdeel J... NEURAL NETWORKS (POSTPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62203F 6. AUTHOR(S) Abdeel J. Roman and

  3. Receiving beam patterns in the horizontal plane of a harbor porpoise (Phocoena phocoena)

    Science.gov (United States)

    Kastelein, Ronald A.; Janssen, Mirjam; Verboom, Willem C.; de Haan, Dick

    2005-08-01

    Receiving beam patterns of a harbor porpoise were measured in the horizontal plane, using narrow-band frequency modulated signals with center frequencies of 16, 64, and 100 kHz. Total signal duration was 1000 ms, including a 200 ms rise time and 300 ms fall time. The harbor porpoise was trained to participate in a psychophysical test and stationed itself horizontally in a specific direction in the center of a 16-m-diameter circle consisting of 16 equally-spaced underwater transducers. The animal's head and the transducers were in the same horizontal plane, 1.5 m below the water surface. The go/no-go response paradigm was used; the animal left the listening station when it heard a sound signal. The method of constants was applied. For each transducer the 50% detection threshold amplitude was determined in 16 trials per amplitude, for each of the three frequencies. The beam patterns were not symmetrical with respect to the midline of the animal's body, but had a deflection of 3-7° to the right. The receiving beam pattern narrowed with increasing frequency. Assuming that the pattern is rotation-symmetrical according to an average of the horizontal beam pattern halves, the receiving directivity indices are 4.3 at 16 kHz, 6.0 at 64 kHz, and 11.7 dB at 100 kHz. The receiving directivity indices of the porpoise were lower than those measured for bottlenose dolphins. This means that harbor porpoises have wider receiving beam patterns than bottlenose dolphins for the same frequencies. Directivity of hearing improves the signal-to-noise ratio and thus is a tool for a better detection of certain signals in a given ambient noise condition.

  4. FLOW DISTRIBUTION IN A SOLAR COLLECTOR PANEL WITH HORIZONTAL ABSORBER STRIPS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Shah, Louise Jivan; Furbo, Simon

    2007-01-01

    The objective of this work is to theoretically and experimentally investigate the flow and temperature distribution in a solar collector panel with an absorber consisting of horizontal strips. Fluid flow and heat transfer in the collector panel are studied by means of computational fluid dynamics...... (CFD) calculations. Further, experimental investigations of a 12.5 m² solar collector panel with 16 parallel connected horizontal fins are carried out. The flow distribution through the absorber is evaluated by means of temperature measurements on the backside of the absorber tubes. The measured...... collector fluid, and by increased collector tilt and inlet temperature, the flow distribution gets worse resulting in a decreased collector efficiency and an increased risk of boiling in the upper part of the collector panel. Keywords: Solar collector; Flow distribution; Computational Fluid Dynamics (CFD...

  5. Flow distribution in a solar collector panel with horizontally inclined absorber strips

    DEFF Research Database (Denmark)

    Fan, Jianhua; Shah, Louise Jivan; Furbo, Simon

    2007-01-01

    The objective of this work is to theoretically and experimentally investigate the flow and temperature distribution in a solar collector panel with an absorber consisting of horizontally inclined strips. Fluid flow and heat transfer in the collector panel are studied by means of computational fluid...... dynamics (CFD) calculations. Further, experimental investigations of a 12.5 m(2) solar collector panel with 16 parallel connected horizontal fins are carried out. The flow distribution through the absorber is evaluated by means of temperature measurements on the backside of the absorber tubes. The measured...... rate, properties of solar collector fluid, solar collector fluid inlet temperature and collector tilt angle are shown. The flow distribution through the absorber fins is uniform if high flow rates are used. By decreased flow rate and decreased content of glycol in the glycol/water mixture used as solar...

  6. The effect of evaporator operating parameters on the flow patterns inside horizontal pipes

    Science.gov (United States)

    Tong, Lige; Li, Haiyan; Wang, Li; Sun, Xinxing; Xie, Yunfei

    2011-08-01

    A general and simple model for simulating the steady state behaviors of air-to-refrigerant fin-and-tube evaporator is introduced with the focus on the detailed flow patterns inside the tubes. In order to simulate the heat transfer between air and the working fluid, the evaporator is divided into a number of control volumes. Empirical correlations from literature were also adopted to estimate the void fraction, the internal and external heat transfer coefficients, and the pressure drops. Simulations were performed to study the effects of varying inlet air temperature, refrigerant mass flow rate and evaporation pressure on the flow patterns inside the horizontal pipe of the evaporator. The simulation results indicate that the proposed model can be used to predict flow patterns well. The predicted results of the model agree well with experimental results, the difference is within ±3% for the cooling capacity, and is within ±0.2% for refrigerant evaporation temperature.

  7. Two-phase flow properties of a horizontal fracture: The effect of aperture distribution

    Science.gov (United States)

    Ye, Zuyang; Liu, Hui-Hai; Jiang, Qinghui; Zhou, Chuangbing

    2015-02-01

    A systematic numerical method has been presented to investigate the constitutive relationships between two-phase flow properties of horizontal fractures and aperture distributions. Based on fractal geometry, single rough-walled fractures are generated numerically by modified successive random addition (SRA) method and then aperture distributions with truncated Gaussian distribution are formed by shear displacement between lower and upper surfaces. (The truncated Gaussian distribution is used to describe aperture evolution under different normal stresses.) According to the assumption of two-dimensional porous media and local parallel plate model, invasion percolation approach is employed to model the two-phase flow displacement (imbibition) in generated horizontal fractures, in which capillary forces are dominant over viscous and gravity forces. For truncated Gaussian distributions, constitutive relationships from numerical simulation are compared to closed-form relationships and a good agreement is obtained. The simulation results indicate strong phase interference with the sum of two phase relative permeability values being less than one in the intermediate saturations. It is found that fracture properties related to residual saturations depend on spatial correlation of aperture distributions. Based on the simulation results, we proposed an empirical relationship between the fracture residual-saturation-rated parameters and the corresponding aperture distributions.

  8. Phase-coexisting patterns, horizontal segregation, and controlled convection in vertically vibrated binary granular mixtures

    Science.gov (United States)

    Ansari, Istafaul Haque; Rivas, Nicolas; Alam, Meheboob

    2018-01-01

    We report patterns consisting of coexistence of synchronous and asynchronous states [for example, a granular gas co-existing with (i) bouncing bed, (ii) undulatory subharmonic waves, and (iii) Leidenfrost-like states] in experiments on vertically vibrated binary granular mixtures in a Hele-Shaw cell. Most experiments have been carried out with equimolar binary mixtures of glass and steel balls of same diameter by varying the total layer height (F ) for a range of shaking acceleration (Γ ). All patterns as well as the related phase diagram in the (Γ ,F ) plane have been reproduced via molecular dynamics simulations of the same system. The segregation of heavier and lighter particles along the horizontal direction is shown to be the progenitor of such phase-coexisting patterns as confirmed in both experiment and simulation. At strong shaking we uncover a partial convection state in which a pair of convection rolls is found to coexist with a Leidenfrost-like state. The crucial role of the relative number density of two species on controlling the buoyancy-driven granular convection is demonstrated. The onset of horizontal segregation can be explained in terms of an anisotropic diffusion tensor.

  9. Experimental investigation of two-phase flow patterns in minichannels at horizontal orientation

    Science.gov (United States)

    Saljoshi, P. S.; Autee, A. T.

    2017-09-01

    Two-phase flow is the simplest case of multiphase flow in which two phases are present for a pure component. The mini channel is considered as diameter below 3.0-0.2 mm and conventional channel is considered diameter above 3.0 mm. An experiment was conducted to study the adiabatic two-phase flow patterns in the circular test section with inner diameter of 1.1, 1.63, 2.0, 2.43 and 3.0 mm for horizontal orientation using air and water as a fluid. Different types of flow patterns found in the experiment. The parameters that affect most of these patterns and their transitions are channel size, phase superficial velocities (air and liquid) and surface tension. The superficial velocity of liquid and gas ranges from 0.01 to 66.70 and 0.01 to 3 m/s respectively. Two-phase flow pattern photos were recorded using a high speed CMOS camera. In this experiment different flow patterns were identified for different tube diameters that confirm the diameter effect on flow patterns in two-phase flows. Stratified flow was not observed for tube diameters less than 3.0 mm. Similarly, wavy-annular flow pattern was not observed in 1.6 and 1.0 mm diameter tubes due to the surface-tension effect and decrease in tube diameter. Buoyancy effects were clearly visible in 2.43 and 3.0 mm diameter tubes flow pattern. It has also observed that as the test-section diameter decreases the transition lines shift towards the higher gas and liquid velocity. However, the result of flow pattern lines in the present study has good agreement with the some of the existing flow patterns maps.

  10. The Efficiency of the Regulation for Horizontal Mergers Among Electricity Distribution Operators in Norway

    DEFF Research Database (Denmark)

    Agrell, Per J.; Bogetoft, Peter; Gammeltvedt, Thor Erik

    2015-01-01

    Merger analysis is usually drawing on concepts derived from competitive horizontal markets, such as market concentration, predatory foreclosure and economies of scale in marketing. In evaluating horizontal mergers among energy network operators, regulators must use different tools to evaluate...... the attractiveness of mergers. Norway is one country having implemented an ex ante regulation for mergers among electricity distribution operators (DSOs). We investigate whether the actual mergers of Norwegian DSOs in the period 1995-2004 can be rationalized as cost saving exercises or whether they should...... be interpreted in other ways. We use Data Envelopment Analysis (DEA) to estimate the potential cost savings from mergers ex ante, and we decompose the gains into gains from learning best practice and from improving economies of scale and scope. Moreover, we compare the sources of post merger performance...

  11. Study on temperature distribution along wellbore of fracturing horizontal wells in oil reservoir

    Directory of Open Access Journals (Sweden)

    Junjun Cai

    2015-12-01

    Full Text Available The application of distributed temperature sensors (DTS to monitor producing zones of horizontal well through a real-time measurement of a temperature profile is becoming increasingly popular. Those parameters, such as flow rate along wellbore, well completion method, skin factor, are potentially related to the information from DTS. Based on mass-, momentum-, and energy-balance equations, this paper established a coupled model to study on temperature distribution along wellbore of fracturing horizontal wells by considering skin factor in order to predict wellbore temperature distribution and analyze the factors influencing the wellbore temperature profile. The models presented in this paper account for heat convective, fluid expansion, heat conduction, and viscous dissipative heating. Arriving temperature and wellbore temperature curves are plotted by computer iterative calculation. The non-perforated and perforated sections show different temperature distribution along wellbore. Through the study on the sensitivity analysis of skin factor and flow rate, we come to the conclusion that the higher skin factor generates larger temperature increase near the wellbore, besides, temperature along wellbore is related to both skin factors and flow rate. Temperature response type curves show that the larger skin factor we set, the less temperature augmenter from toe to heel could be. In addition, larger flow rate may generate higher wellbore temperature.

  12. Atmospheric Test Models and Numerical Experiments for the Simulation of the Global Distributions of Weather Data Transponders III. Horizontal Distributions

    Energy Technology Data Exchange (ETDEWEB)

    Molenkamp, C.R.; Grossman, A.

    1999-12-20

    A network of small balloon-borne transponders which gather very high resolution wind and temperature data for use by modern numerical weather predication models has been proposed to improve the reliability of long-range weather forecasts. The global distribution of an array of such transponders is simulated using LLNL's atmospheric parcel transport model (GRANTOUR) with winds supplied by two different general circulation models. An initial study used winds from CCM3 with a horizontal resolution of about 3 degrees in latitude and longitude, and a second study used winds from NOGAPS with a 0.75 degree horizontal resolution. Results from both simulations show that reasonable global coverage can be attained by releasing balloons from an appropriate set of launch sites.

  13. Horizontal distribution and growth of jellyfish, Aurelia aurita (Linnaeus 1758) sensu lato, in Mikawa Bay, Japan

    OpenAIRE

    Aoki, Kaoru; Yamada, Satoshi; Toyokawa, Masaya; Yasuda, Akira; Kikuchi, Tomohiko

    2012-01-01

    We investigated the occurrence, growth, and horizontal distribution of the moon jelly, Aurelia aurita sensu lato, in Mikawa Bay from April 2007 to November 2008. In May and August 2007, dense populations of adults occurred in the bay mouth. After August, larger individuals with no planula larvae had involuted bells. In March 2008, adults were highly abundant in the western part of the bay. Small-sized moon jellies were observed from March to June, and dense swarms of adults and semi-adults sh...

  14. Determination of the horizontal and vertical distribution of clouds from infrared satellite sounding data

    Science.gov (United States)

    Chahine, M. T.; Susskind, J.

    1982-01-01

    A numerical algorithm, based on a physical inversion of the radiative transfer equation, is developed to retrieve the global distribution of the horizontal cloud cover, the cloud-top pressure levels and their temperature. The algorithm makes use of infrared and microwave temperature sounding data to derive the clear-column vertical temperature profiles and then uses the same infrared sounding data to obtain the corresponding cloud parameters. Experimental verification of this method is carried out using data from the High resolution Infrared Sounder (HIRS) and the Microwave Sounding Unit (MSU) operating on the NOAA weather satellite system.

  15. Characterization of fluid flow patterns and heat transfer in horizontal channel mixed convection

    Energy Technology Data Exchange (ETDEWEB)

    Benderradji, A. [University of Batna, Department of Mechanical Engineering, Batna (Algeria); Haddad, A.; Taher, R.; Medale, M.; Abid, C.; Papini, F. [Technopole de Chateau-Gombert, IUSTI-CNRS UMR 6595, Polytech' Marseille, Marseille (France)

    2008-10-15

    Two mechanisms of roll initiation are highlighted in a horizontal channel flow, uniformly heated from below, at constant heat flux ({gamma}=10, Pr=7, 50{<=}Re{<=}100, 0{<=}Ra{<=}10{sup 6}). The first mechanism is the classical one, it occurs for low Rayleigh numbers and is initiated by the lateral wall effect. The second occurs for higher Rayleigh numbers and combines the previous effect with a supercritical vertical temperature gradient in the lower boundary layer, which simultaneously triggers pairs of rolls in the whole zone in between the two lateral rolls. We have found that in the present configuration, the transition between the two roll initiation mechanisms occurs for Ra/Re{sup 2} {approx}18. Consequently, the heat transfer is significantly enhanced compared to the pure forced convection case owing to the flow pattern responsible of the continuous flooding the heated wall with cold fluid. (orig.)

  16. Changes in retail food and drink distribution in Argentina 2001-2003: Towards new territory horizontalities

    Directory of Open Access Journals (Sweden)

    Josefina Di Nucci

    2007-01-01

    Full Text Available This paper introduces the main changes in the distribution of food and drinks in Argentina, which began with the economic, political and social crisis in 2001. The territory used by some of the social actors involved, such as businesses of different sizes (supermarkets and neighborhood stores and people (consumers, will no longer respond exclusively to a global order or to territorial verticalities. Many of these new tendencies will be led by local norms connected with territorial horizontalities. The most important of these changes is the fact that consumption has become oriented towards: sales, smaller packaging, second and third brands, supermarkets' own brands, new shopping frequencies, a combination of several distribution channels with the so-called "back-to-the-neighborhood" phenomenon, and single-item shopping.

  17. Presentation, distribution pattern, and management of diverticular ...

    African Journals Online (AJOL)

    We embark on this study aimed at evaluating the presentation, distribution pattern, and the management of diverticulosis in our tertiary health facility. Materials and Methods: A prospective descriptive study of the cases of diverticular disease seen between January 2007 and December 2011 at Obafemi Awolowo University ...

  18. Distribution pattern of surgically treated symptomatic prolapsed ...

    African Journals Online (AJOL)

    Background: The pattern of distribution of surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs has been published, though scantily, especially in males. We decided to look at our own series, compare and contrast ours with some of those published. Materials and Methods: We treated 88 locations ...

  19. Seasonal variations and horizontal distribution of precipitation over extratropical continental regions in CMIP5

    Science.gov (United States)

    Hamada, A.; Hirota, N.; Takayabu, Y. N.

    2012-12-01

    Seasonal variations and horizontal distribution of precipitation over extratropical continental regions by the CMIP5 climate models in their historical runs are evaluated, in comparison with GPCP, CMAP, daily gridded gauge data APHRODITE, and with various reanalysis data. Eight regions are selected over the Eastern Europe, northwestern Russia, Mongolia, northeastern Russia, Alaska, western US, eastern Canada, and eastern US. It is shown that precipitation reproducibility over extratropical continental regions in climate models widely varies depending on regions and seasons, probably attributed to the matching of the precipitation characteristics and treatments of physical processes in the climate models. In some regions, additional treatments of physical processes such as those implemented in the Earth System Models improve the result, while in other regions, horizontal resolution looks essential for the improvements. The reproducibility also varies depending on seasons in a same region, for example, differs between summer and winter in the Eastern Europe. It is also noted that estimated rain amounts considerably vary among GPCP, CMAP, and APHRODITE. Acknowledgment: This study is supported by the 6th GPM/TRMM RA of JAXA, Green Network of Excellence (GRENE) Program by the Ministry of Education, Culture, Sports, Science and Technology, Japan, and Environment Research and Technology Development Fund (A-1201) of the Ministry of the Environment, Japan.

  20. Periodically distributed objects with quasicrystalline diffraction pattern

    Energy Technology Data Exchange (ETDEWEB)

    Wolny, Janusz, E-mail: wolny@fis.agh.edu.pl; Strzalka, Radoslaw [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland); Kuczera, Pawel [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland); Laboratory of Crystallography, ETH Zurich, Wolfgang-Pauli-Strasse 10, CH-8093 Zurich (Switzerland)

    2015-03-30

    It is possible to construct fully periodically distributed objects with a diffraction pattern identical to the one obtained for quasicrystals. These objects are probability distributions of distances obtained in the statistical approach to aperiodic structures distributed periodically. The diffraction patterns have been derived by using a two-mode Fourier transform—a very powerful method not used in classical crystallography. It is shown that if scaling is present in the structure, this two-mode Fourier transform can be reduced to a regular Fourier transform with appropriately rescaled scattering vectors and added phases. Detailed case studies for model sets 1D Fibonacci chain and 2D Penrose tiling are discussed. Finally, it is shown that crystalline, quasicrystalline, and approximant structures can be treated in the same way.

  1. Horizontal temperature distribution in a plus-energy house: cooling season measurements

    DEFF Research Database (Denmark)

    Kazanci, Ongun Berk; Olesen, Bjarne W.

    2015-01-01

    The present study is concerned with the air and operative temperatures at different locations in a detached, one-story, single family, plus-energy house. The house was located in Denmark and it has been used as a full-scale experimental facility with heated dummies to simulate occupants living...... of indoor environment in this single space could be challenging. The measurement of horizontal temperature distribution could address these issues and provide a means of improvement, if necessary. The measurements showed that a uniform thermal indoor environment was achieved inside the house. The average...... would follow the temperature changes in the occupied zone closely and, thus, would provide a good indication of the thermal indoor environment to the control system....

  2. Vertical and horizontal distributions of microbial abundances and enzymatic activities in propylene-glycol-affected soils.

    Science.gov (United States)

    Biró, Borbála; Toscano, Giuseppe; Horváth, Nikoletta; Matics, Heléna; Domonkos, Mónika; Scotti, Riccardo; Rao, Maria A; Wejden, Bente; French, Helen K

    2014-01-01

    The natural microbial activity in the unsaturated soil is vital for protecting groundwater in areas where high loads of biodegradable contaminants are supplied to the surface, which usually is the case for airports using aircraft de-icing fluids (ADF) in the cold season. Horizontal and vertical distributions of microbial abundance were assessed along the western runway of Oslo Airport (Gardermoen, Norway) to monitor the effect of ADF dispersion with special reference to the component with the highest chemical oxygen demand (COD), propylene glycol (PG). Microbial abundance was evaluated by several biondicators: colony-forming units (CFU) of some physiological groups (aerobic and anaerobic heterotrophs and microscopic fungi), most probable numbers (MPN) of PG degraders, selected catabolic enzymatic activities (fluorescein diacetate (FDA) hydrolase, dehydrogenase, and β-glucosidase). High correlations were found between the enzymatic activities and microbial counts in vertical soil profiles. All microbial abundance indicators showed a steep drop in the first meter of soil depth. The vertical distribution of microbial abundance can be correlated by a decreasing exponential function of depth. The horizontal trend of microbial abundance (evaluated as total aerobic CFU, MPN of PG-degraders, and FDA hydrolase activity) assessed in the surface soil at an increasing distance from the runway is correlated negatively with the PG and COD loads, suggesting the relevance of other chemicals in the modulation of microbial growth. The possible role of potassium formate, component of runway de-icers, has been tested in the laboratory by using mixed cultures of Pseudomonas spp., obtained by enrichment with a selective PG medium from soil samples taken at the most contaminated area near the runway. The inhibitory effect of formate on the growth of PG degraders is proven by the reduction of biomass yield on PG in the presence of formate.

  3. Vertical and horizontal distribution of wind speed and air temperature in a dense vegetation canopy

    NARCIS (Netherlands)

    Jacobs, A.F.G.; van Boxel, J.H.; El-Kilani, R.M.M.

    1995-01-01

    Wind speed and temperature were measured within a corn row canopy to investigate horizontal and vertical variability of the mean wind speed and temperature. It appears that the mean wind speed can vary between 20% and 30% from its horizontal mean value. In the narrow row crop, the horizontal mean

  4. Fat distribution patterns in young amenorrheic females.

    Science.gov (United States)

    Kirchengast, S; Huber, J

    2001-06-01

    The present study analyzes body fat distribution, a well-known and important indicator of reproductive capability, in young women between 18 and 28 years of age (mean=23.3 years) suffering from secondary amenorrhea and therefore temporary infertility resulting from self-starvation. Body composition parameters estimated by means of dual energy x-ray absorptiometry and the fat distribution index, indicating body shape, were compared with those of healthy controls. Although members of the infertile, amenorrheic group exhibited dramatically low body weight and total amount of body fat, and therefore a marked negative energy balance in comparison with the healthy controls, the sex-specific fat distribution patterns did not differ between infertile and fertile young women. In contrast, the lower the weight and total fat amount, the more gynoid the fat distribution, even in infertile women. This observation may be interpreted in an evolutionary sense: Our ancestors had to cope with frequent food shortages, even starvation, and therefore lengthy periods of negative energy balance. In addition to pregnancy and lactation, temporary infertility as a result of long-term negative energy balance was not an uncommon phenomenon in female life histories. Nevertheless, after a time of plenty, reproductive function recovered, and therefore the gynoid fat distribution patterns in temporarily infertile young women may be interpreted as signal of reproductive capability, which resumes after a time of surplus.

  5. Horizontal distribution of Fukushima-derived radiocesium in zooplankton in the northwestern Pacific Ocean

    Directory of Open Access Journals (Sweden)

    M. Kitamura

    2013-08-01

    Full Text Available The magnitude of the 9.0 Tohoku earthquake and the ensuing tsunami on 11 March 2011, inflicted heavy damage on the Fukushima Dai-ichi nuclear power plant (FNPP1. Fission products were emitted, falling over a broad range in the Northern Hemisphere, and water contaminated with radionuclides leaked into the ocean. In this study, we described the horizontal distribution of the Fukushima-derived radiocesium in zooplankton and in seawater in the western North Pacific Ocean (500–2100 km from the FNPP1 10 months after the accident. 134Cs and 137Cs were detected in zooplankton and seawater from all the stations. Because of its short half-life, the 134Cs detected in our samples could only be derived from the FNPP1 accident. The highest 137Cs activity in zooplankton was the same order of magnitude as it was one month after the accident, and average activity was one or two orders of magnitude higher than 137Cs activities observed before the accident around Japan. Horizontally, the radiocesium activity concentrations in zooplankton were high at around 25° N while those in surface seawater were high at around the transition area between the Kuroshio and the Oyashio currents (36–40° N. We observed subsurface radiocesium maxima in density range of the North Pacific Subtropical Mode Water and the occurrence of many diel vertical migratory zooplankton. These suggested that the high activity concentrations in the subtropical zooplankton at around 25° N were connected to the subsurface radiocesium and active vertical migration of zooplankton. However, the high activity concentrations of radiocesium in subsurface seawater did not necessarily correlate with the higher radiocesium activity in zooplankton. Activity concentrations of radiocesium in zooplankton might be influenced not only by the environmental radiocesium activity concentrations but also by other factors, which are still unknown.

  6. Biomechanics of gecko locomotion: the patterns of reaction forces on inverted, vertical and horizontal substrates.

    Science.gov (United States)

    Wang, Zhouyi; Dai, Zhendong; Ji, Aihong; Ren, Lei; Xing, Qiang; Dai, Liming

    2015-02-04

    The excellent locomotion ability of geckos on various rough and/or inclined substrates has attracted scientists' attention for centuries. However, the moving ability of gecko-mimicking robots on various inclined surfaces still lags far behind that of geckos, mainly because our understanding of how geckos govern their locomotion is still very poor. To reveal the fundamental mechanism of gecko locomotion and also to facilitate the design of gecko-mimicking robots, we have measured the reaction forces (RFs) acting on each individual foot of moving geckos on inverted, vertical and horizontal substrates (i.e. ceiling, wall and floor), have associated the RFs with locomotion behaviors by using high-speed camera, and have presented the relationships of the force components with patterns of reaction forces (PRFs). Geckos generate different PRF on ceiling, wall and floor, that is, the PRF is determined by the angles between the direction of gravity and the substrate on which geckos move. On the ceiling, geckos produce reversed shear forces acting on the front and hind feet, which pull away from the body in both lateral and fore-aft directions. They use a very large supporting angle from 21° to 24° to reduce the forces acting on their legs and feet. On the floor, geckos lift their bodies using a supporting angle from 76° to 78°, which not only decreases the RFs but also improves their locomotion ability. On the wall, geckos generate a reliable self-locking attachment by using a supporting angle of 14.8°, which is only about half of the critical angle of detachment.

  7. Breast compression in mammography: pressure distribution patterns

    Energy Technology Data Exchange (ETDEWEB)

    Dustler, Magnus; Froejd, Patrik; Mattsson, Soeren; Tingberg, Anders; Foernvik, Daniel [Medical Radiation Physics, Lund Univ., Skaane Univ. Hospital, Malmoe (Sweden)], E-mail: Magnus.Dustler@med.lu.se; Andersson, Ingvar; Zackrisson, Sophia [Diagnostic Centre of Imaging and Functional Medicine, Lund Univ., Skaane Univ. Hospital, Malmoe (Sweden); Brorson, Haakan [Plastic and Reconstructive Surgery, Dept. of Clinical Sciences Malmoe, Lund Univ., Skaane Univ. Hospital, Malmoe (Sweden)

    2012-11-15

    Background Breast compression is important in mammography in order to improve image quality, better separate tissue components, and reduce absorbed dose to the breast. In this study we use a method to measure and visualize the distribution of pressure over a compressed breast in mammography. Purpose To measure and describe the pressure distribution over the breast as a result of applied breast compression in mammography. Material and Methods One hundred and three women aged 40.7-74.3 years (median, 48.9 years) invited for mammographic screening consented to take part in this study. They were subjected to two additional breast compressions of the left breast (standard force and approximately 50% reduction). Pressure images of the compressed breast were obtained using force sensing resistor (FSR) sensors placed underneath the compression plate. Subjects rated their experience of pain on a visual analogue scale (VAS). Results Four pressure patterns were identified, fitting 81 of the 103 breasts, which were grouped accordingly. The remaining 22 breasts were found to correspond to a combination of any two patterns. Two groups (43 breasts) showed pressure mainly over the juxtathoracic part of the breast, had significantly greater breast thickness (P = 0.003) and had a lower mean pressure over dense tissue (P < 0.0001) than those with more evenly distributed pressure. Reducing compression force increased average breast thickness by 1.8 mm (P < 0.0001). Conclusion The distribution of pressure differed greatly between breasts. In a large proportion of breasts the compression plate did not provide optimal compression of the breast, the compression force being absorbed in juxtathoracic structures.

  8. Evaluation of ambient dose equivalent rates influenced by vertical and horizontal distribution of radioactive cesium in soil in Fukushima Prefecture

    CERN Document Server

    Malins, Alex; Nakama, Shigeo; Saito, Tatsuo; Okumura, Masahiko; Machida, Masahiko; Kitamura, Akihiro

    2016-01-01

    The air dose rate in an environment contaminated with 134Cs and 137Cs depends on the amount, depth profile and horizontal distribution of these contaminants within the ground. This paper introduces and verifies a tool that models these variables and calculates ambient dose equivalent rates at 1 m above the ground. Good correlation is found between predicted dose rates and dose rates measured with survey meters in Fukushima Prefecture in areas contaminated with radiocesium from the Fukushima Dai-ichi Nuclear Power Plant accident. This finding is insensitive to the choice for modelling the activity depth distribution in the ground using activity measurements of collected soil layers, or by using exponential and hyperbolic secant fits to the measurement data. Better predictions are obtained by modelling the horizontal distribution of radioactive cesium across an area if multiple soil samples are available, as opposed to assuming a spatially homogeneous contamination distribution. Reductions seen in air dose rate...

  9. Distributive Conjugal Transfer: New Insights into Horizontal Gene Transfer and Genetic Exchange in Mycobacteria

    Science.gov (United States)

    Derbyshire, Keith M.; Gray, Todd A.

    2014-01-01

    The last decade has seen an explosion in the application of genomic tools across all biological disciplines. This is also true for mycobacteria, where whole genome sequences are now available for pathogens and non-pathogens alike. Genomes within the Mycobacterium tuberculosis Complex (MTBC) bear the hallmarks of horizontal gene transfer (HGT). Conjugation is the form of HGT with the highest potential capacity and evolutionary influence. Donor and recipient strains of Mycobacterium smegmatis actively conjugate upon co-culturing in biofilms and on solid media. Whole genome sequencing of the transconjugant progeny demonstrated the incredible scale and range of genomic variation that conjugation generates. Transconjugant genomes are complex mosaics of the parental strains. Some transconjugant genomes are up to one-quarter donor-derived, distributed over 30 segments. Transferred segments range from ~50 bp to ~225,000 bp in length, and are exchanged with their recipient orthologs all around the genome. This unpredictable genome-wide infusion of DNA sequences is called Distributive Conjugal Transfer (DCT), to distinguish it from traditional oriT-based conjugation. The mosaicism generated in a single transfer event resembles that seen from meiotic recombination in sexually reproducing organisms, and contrasts with traditional models of HGT. This similarity allowed the application of a GWAS-like approach to map the donor genes that confer a donor mating identity phenotype. The mating identity genes map to the esx1 locus, expanding the central role of ESX-1 function in conjugation. The potential for DCT to instantaneously blend genomes will affect how we view mycobacterial evolution, and provide new tools for the facile manipulation of mycobacterial genomes. PMID:25505644

  10. [Instability pattern of acromioclavicular joint dislocations type Rockwood III: relevance of horizontal instability].

    Science.gov (United States)

    Wellmann, M; da Silva, G; Lichtenberg, S; Magosch, P; Habermeyer, P

    2013-04-01

    There is no evidence-based treatment algorithm established for acromioclavicular joint (AC joint) dislocation classified as type Rockwood III injury. Recent meta-analyses revealed no advantage of surgical treatment compared to the non-operative approach. Both surgical and non-surgical approaches have been reported with inconsistent results. Therefore, the hypothesis of the current study was that patients classified as having Rockwood grade III injury may have different degrees of horizontal AC joint instability. A total of 18 consecutive patients who had sustained a dislocation of the AC joint classified as Rockwood III were evaluated radiologically to quantify the horizontal instability of the AC joint. The specific radiological investigation included lateral stress x-rays (Alexander view) und axial stress x-rays with the affected arm in a horizontal adduction position. The dynamic horizontal instability of the AC joint was found to be independent of the vertical dislocation measured in the Rockwood classification. For further treatment studies Rockwood III injuries should be distinguished in patients presenting with or without a substantial horizontal AC joint instability.

  11. Color Distribution Pattern Metric for Person Reidentification

    Directory of Open Access Journals (Sweden)

    Yingsheng Ye

    2017-01-01

    Full Text Available Accompanying the growth of surveillance infrastructures, surveillance IP cameras mount up rapidly, crowding Internet of Things (IoT with countless surveillance frames and increasing the need of person reidentification (Re-ID in video searching for surveillance and forensic fields. In real scenarios, performance of current proposed Re-ID methods suffers from pose and viewpoint variations due to feature extraction containing background pixels and fixed feature selection strategy for pose and viewpoint variations. To deal with pose and viewpoint variations, we propose the color distribution pattern metric (CDPM method, employing color distribution pattern (CDP for feature representation and SVM for classification. Different from other methods, CDP does not extract features over a certain number of dense blocks and is free from varied pedestrian image resolutions and resizing distortion. Moreover, it provides more precise features with less background influences under different body types, severe pose variations, and viewpoint variations. Experimental results show that our CDPM method achieves state-of-the-art performance on both 3DPeS dataset and ImageLab Pedestrian Recognition dataset with 68.8% and 79.8% rank 1 accuracy, respectively, under the single-shot experimental setting.

  12. Fish larvae at fronts: Horizontal and vertical distributions of gadoid fish larvae across a frontal zone at the Norwegian Trench

    DEFF Research Database (Denmark)

    Munk, Peter

    2014-01-01

    The reproduction and early life history of many fish species are linked to the physical and biological characteristics of fronts. In order to ascertain linkages between frontal physics and fish larvae, we investigated distributional differences among gadoid fish larvae comparing these to both...... horizontal and vertical variability in hydrography and abundances of potential copepod prey The investigation was carried out at a frontal zone along the Norwegian Trench in the northern North Sea, and was based on a series of cross-bathymetric sampling transects. Tows with a large ring net and an opening......-closing net were used for describing fish larval horizontal and vertical distributions, while a submersible pump was used for describing vertical distributions of copepods. Hydrographic profiles and current velocity measurements were used to outline variability in temperature, salinity and current structure...

  13. Horizontal distribution and levels of heavy metals in the biggest snowstorm in a century in Shenyang, China.

    Science.gov (United States)

    An, Jing; Zhou, Qixing; Liu, Weitao; Ren, Liping

    2008-01-01

    The horizontal distribution and levels of heavy metals in the biggest snowstorm in Shenyang since 1904 were investigated by analyzing 4 metals (As, Cd, Pb, and Cu) in a series of ultraclean samples collected from 17 sites distributed in different regions of the Shenyang area, China. The results showed that the concentrations of all the 4 heavy metals in snow from the industrial regions were high, up to 7.3 (As), 2.2 (Cd), 850.0 (Pb), and 0.197-20.2 (Cu) microg/kg, respectively. In the suburb, in contrast, their concentrations were not detected, except for As. Because of the long-term application of arsenical pesticides and herbicides, As was detected in the snow samples which collected on the farm. As, Cd, and Pb were also detected in the snow samples collected from the parks, the residential areas, and the commercial districts mainly by reason of human activities. In a sense, long-term industrial activities, traffic activities, coal combustion, and agricultural activities affected the horizontal distribution and levels of these heavy metals in snow differently. The data relating to the horizontal distribution and concentrations of heavy metals in the snow under extreme climatic conditions can provide with a unique snapshot of environmental pollution situation and behaviors in urban areas.

  14. Stress distribution in maxillary first molar periodontium using straight pull headgear with vertical and horizontal tubes: A finite element analysis

    OpenAIRE

    Feizbakhsh, Masood; Kadkhodaei, Mahmoud; Zandian, Dana; Hosseinpour, Zahra

    2017-01-01

    Background: One of the most effective ways for distal movement of molars to treat Class II malocclusion is using extraoral force through a headgear device. The purpose of this study was the comparison of stress distribution in maxillary first molar periodontium using straight pull headgear in vertical and horizontal tubes through finite element method. Materials and Methods: Based on the real geometry model, a basic model of the first molar and maxillary bone was obtained using three-dimen...

  15. Spatial distribution of human and canine visceral leishmaniasis in Belo Horizonte, Minas Gerais State, Brasil, 1994-1997 Distribuição espacial da leishmaniose visceral humana e canina em Belo Horizonte, Minas Gerais, Brasil, 1994-1997

    Directory of Open Access Journals (Sweden)

    Cláudia Di Lorenzo Oliveira

    2001-10-01

    Full Text Available In this paper, we present spatial analysis of the association between all incidents cases of human Visceral Leishmaniasis and seropositive dogs, from 1994 to 1997 in Belo Horizonte, a large Brazilian city. We geocoded 158 human cases and 11,048 seropositive dogs and compared canine prevalence rates with Human Bayesian Incidence rates in the same areas. We also used Knox's test to evaluate the hypothesis of space-time clustering of human cases in the period. Additionally, we used Kernel's maps for seropositive dogs distribution and located the human cases in the resulting smooth maps. We concluded that human and dog rates are correlated. Also, the Visceral Leishmaniasis in Belo Horizonte spread quickly, but apart from the rates' magnitude, it has kept the same spatial pattern through time. We believe it is possible to use this technique to choose areas to implement control measures against Visceral Leishmaniasis in a more efficient way.Neste artigo, apresentamos uma análise espacial da associação entre todos os casos incidentes de leishmaniose visceral e em cães soropositivos ocorridos em Belo Horizonte no período de 1994 a 1997. Geocodificamos 158 casos humanos e 11.048 cães positivos, comparamos as taxas de prevalência canina por área e as taxas Bayesianas de incidência da doença humana nas mesmas áreas. Usamos o teste de Knox para testar a hipótese de cluster espaço temporal entre os casos humanos no período examinado. Adicionalmente, construímos Mapas de Kernel para cães soropositivos e sobrepusemos os casos humanos em quatro áreas. Os resultados apontam para correlação entre casos humanos e caninos. Além disso, a leishmaniose visceral espalhou-se rapidamente em Belo Horizonte, embora tenha mantido o mesmo padrão durante os anos analisados. Acreditamos ser possível o uso das técnicas empregadas para priorizar áreas onde as medidas de controle devem ser implementadas.

  16. Distribution and behaviour of the amphipod, Talorchestia capensis ...

    African Journals Online (AJOL)

    Muir 1977). No such horizontal distribution pattern was found for T. capensis at Sundays River beach. Although no horizontal segregation of size classes exists, there is a clear vertical distribution pattern, juveniles occurring near the surface and ...

  17. Investigation on Effect of Gravity Level on Bubble Distribution and Liquid Turbulence Modification for Horizontal Channel Bubbly Flow

    Science.gov (United States)

    Pang, M. J.; Wei, J. J.; Yu, B.

    2017-08-01

    Bubbly flows in the horizontal channel or pipe are often seen in industrial engineering fields, so it is very necessary to fully understand hydrodynamics of horizontal bubbly flows so as to improve industrial efficiency and to design an efficient bubbly system. In this paper, in order to fully understand mechanisms of phase distribution and liquid-phase turbulence modulation in the horizontal channel bubbly flow, the influence of gravity level on both of them were investigated in detail with the developed Euler-Lagrange two-way coupling method. For the present investigation, the buoyance on bubbles in both sides of the channel always points to the corresponding wall in order to study the liquid-phase turbulence modulation by bubbles under the symmetric physical condition. The present investigation shows that the gravity level has the important influence on the wall-normal distribution of bubbles and the liquid-phase turbulence modulation; the higher the gravity level is, the more bubbles can overcome the wall-normal resistance to accumulate near the wall, and the more obvious the liquid-phase turbulence modulation is. It is also discovered that interphase forces on the bubbles are various along the wall-normal direction, which leads to the fact that the bubble located in different wall-normal places has a different wall-normal velocity.

  18. Distribution patterns of Iberian Carabidae (Insecta, Coleoptera

    Directory of Open Access Journals (Sweden)

    Serrano, José

    2003-12-01

    Full Text Available We have categorised the 1336 species and subspecies of the Iberian Peninsula according to the chorotype classification proposed by Vigna Taglianti et al. (1992, modified by the addition of new chorotypes. The Iberian Peninsula is noticeable among the different European and Circum-Mediterranean regions by the high proportion of endemic taxa (43.1%. The old age and stability of the northern half, the extreme position of the Peninsula within the Eurasiatic continent, alpine tectonics and abundance of caves are among the factors that have probably contributed to the origin of a distinctive fauna. Taxa with a large distribution pattern are predominant at a regional scale; the proportion of endemic taxa increases to the North and in mountain regions; Mediterranean elements are more frequent in the South whereas European elements increase in the northern half. Adaptation to a Mediterranean climatic regime and dispersal are two of the factors causing these patterns. The Peninsula is poor in Afrotropical elements, probably because of the strong isolation derived from the Sahara Desert. The Balearic Islands have high proportions of widely distributed and Mediterranean taxa, what suggests a main role of dispersal in the colonisation of the archipelago. The proportion of endemic taxa in Mallorca (7.8% is intermediate between that of Sardinia and Sicily; in spite of a relatively long isolation, the Balearic Islands are small in size and moderately rich in caves, what explains that most endemic taxa are found in the lowlands.

    Se han categorizado las 1336 especies y subespecies de la fauna ibérica de Carabidae, usando los corotipos propuestos por Vigna Taglianti et al. (1992, los cuales se han completado con algunos otros adicionales. La Península Ibérica destaca entre las diversas regiones europeas y circunmediterráneas por la elevada proporción de elementos endémicos (43,1%. La antigüedad y estabilidad de la mitad norte

  19. Distribuição vertical e horizontal de temperaturas do ar em ambientes protegidos Vertical and horizontal distribution of air temperature in a plastic greenhouse

    Directory of Open Access Journals (Sweden)

    Raquel A. Furlan

    2002-04-01

    space distribution of the air temperature inside the greenhouse atmosphere, thermo couples of (copper-constantan were installed, forming a grid spaced 3.0 m horizontally, at the heights of 0.5, 1.0, 2.0, 3.0 and 4.0 m above the soil. The data were stored every 15 min by a system of data acquisition. The fog system constituted of two lines with 70 foggers, installed at 3.0 m height and operating at a pressure of 20 kPa. The fog system did not affect the vertical temperature gradient, maintaining the tendency of increase of the air temperature with the height in relation to the soil level. While the effect of fog system to decrease the air temperature was effective when the system was on. The representation of the air temperature distribution in space inside the greenhouse at different height levels was done by isotherm surfaces. It was verified that the fog system had the highest effect in the homogenization of the air temperature distribution inside the greenhouse at the height of 2.0 m from the soil.

  20. Characteristics of two-phase flow pattern transitions and pressure drop of five refrigerants in horizontal circular small tubes

    Energy Technology Data Exchange (ETDEWEB)

    Pamitran, A.S. [Department of Mechanical Engineering, University of Indonesia, Kampus Baru UI, Depok 16424 (Indonesia); Choi, Kwang-Il [Graduate School, Chonnam National University, San 96-1, Dunduk-Dong, Yeosu, Chonnam 550-749 (Korea); Oh, Jong-Taek [Department of Refrigeration and Air Conditioning Engineering, Chonnam National University, San 96-1, Dunduk-Dong, Yeosu, Chonnam 550-749 (Korea); Hrnjak, Pega [Department of Mechanical Science and Engineering, ACRC, University of Illinois at Urbana-Champaign, 1206 West Green Street, Urbana, IL 61801 (United States)

    2010-05-15

    An experimental investigation on the characteristics of two-phase flow pattern transitions and pressure drop of R-22, R-134a, R-410A, R-290 and R-744 in horizontal small stainless steel tubes of 0.5, 1.5 and 3.0 mm inner diameters is presented. Experimental data were obtained over a heat flux range of 5-40 kW/m{sup 2}, mass flux range of 50-600 kg/(m{sup 2} s), saturation temperature range of 0-15 C, and quality up to 1.0. Experimental data were evaluated with Wang et al. and Wojtan et al. [Wang, C.C., Chiang, C.S., Lu, D.C., 1997. Visual observation of two-phase flow pattern of R-22, R-134a, and R-407C in a 6.5-mm smooth tube. Exp. Therm. Fluid Sci. 15, 395-405; Wojtan, L., Ursenbacher, T., Thome, J.R., 2005. Investigation of flow boiling in horizontal tubes: part I - a new diabatic two-phase flow pattern map. Int. J. Heat Mass Transfer 48, 2955-2969.] flow pattern maps. The effects of mass flux, heat flux, saturation temperature and inner tube diameter on the pressure drop of the working refrigerants are reported. The experimental pressure drop was compared with the predictions from some existing correlations. A new two-phase pressure drop model that is based on a superposition model for two-phase flow boiling of refrigerants in small tubes is presented. (author)

  1. Horizontal distribution of invertebrate larvae around the oceanic island of Gran Canaria: the effect of mesoscale variability

    Directory of Open Access Journals (Sweden)

    José María Landeira

    2009-12-01

    Full Text Available In October 1991, the horizontal distribution of invertebrate larvae was studied in the waters surrounding the island of Gran Canaria (Canary Islands. The cruise was typified by the presence of three recurrent mesoscale hydrographic structures: a cyclonic eddy southwest of the island, a warm lee region downstream of the island and the offshore boundary of an upwelling filament from the African coast reaching the southeast of the island. Decapod larvae were the most abundant group. In general, a rather high spatial variability was found. The horizontal distribution of the invertebrate larvae groups showed that the highest values of abundance occurred in an elongated zone around the island oriented in the overall direction of flow, leeward and windward of the island, while the lowest values occurred off the eastern and western flanks of the islands. On the other hand, Stomatopoda and Mollusca larvae showed a distribution associated with the boundary of the upwelling filament and decapod larvae of pelagic species were distributed around the eddy structure. Our results suggest specific retention mechanisms for the larvae of neritic invertebrate populations that are related to the particular physical oceanography around Gran Canaria.

  2. Dust as probe for horizontal field distribution in low pressure gas discharges

    CERN Document Server

    Hartmann, Peter; Reyes, Jorge C; Matthews, Lorin S; Hyde, Truell W

    2014-01-01

    Using dust grains as probes in gas discharge plasma is a very promising, but at the same time very challenging method, as the individual external control of dust grains has to be solved. We propose and demonstrate the applicability of the RotoDust experiment, where the well controlled centrifugal force is balanced by the horizontal confinement field in plane electrode argon radio frequency gas discharges. We have reached a resolution of 0.1 V/cm for the electric field. This technique is used to verify numerical simulations and to map symmetry properties of the confinement in dusty plasma experiments using a glass box.

  3. Stress distribution in maxillary first molar periodontium using straight pull headgear with vertical and horizontal tubes: A finite element analysis.

    Science.gov (United States)

    Feizbakhsh, Masood; Kadkhodaei, Mahmoud; Zandian, Dana; Hosseinpour, Zahra

    2017-01-01

    One of the most effective ways for distal movement of molars to treat Class II malocclusion is using extraoral force through a headgear device. The purpose of this study was the comparison of stress distribution in maxillary first molar periodontium using straight pull headgear in vertical and horizontal tubes through finite element method. Based on the real geometry model, a basic model of the first molar and maxillary bone was obtained using three-dimensional imaging of the skull. After the geometric modeling of periodontium components through CATIA software and the definition of mechanical properties and element classification, a force of 150 g for each headgear was defined in ABAQUS software. Consequently, Von Mises and Principal stresses were evaluated. The statistical analysis was performed using T-paired and Wilcoxon nonparametric tests. Extension of areas with Von Mises and Principal stresses utilizing straight pull headgear with a vertical tube was not different from that of using a horizontal tube, but the numerical value of the Von Mises stress in the vertical tube was significantly reduced ( P 0/05). Based on the results, when force applied to the straight pull headgear with a vertical tube, Von Mises stress was reduced significantly in comparison with the horizontal tube. Therefore, to correct the mesiolingual movement of the maxillary first molar, vertical headgear tube is recommended.

  4. Variation in the Genetic Repertoire of Viruses Infecting Micromonas pusilla Reflects Horizontal Gene Transfer and Links to Their Environmental Distribution.

    Science.gov (United States)

    Finke, Jan F; Winget, Danielle M; Chan, Amy M; Suttle, Curtis A

    2017-05-19

    Prasinophytes, a group of eukaryotic phytoplankton, has a global distribution and is infected by large double-stranded DNA viruses (prasinoviruses) in the family Phycodnaviridae . This study examines the genetic repertoire, phylogeny, and environmental distribution of phycodnaviruses infecting Micromonas pusilla , other prasinophytes and chlorophytes. Based on comparisons among the genomes of viruses infecting M. pusilla and other phycodnaviruses, as well as the genome from a host isolate of M. pusilla , viruses infecting M. pusilla (MpVs) share a limited set of core genes, but vary strongly in their flexible pan-genome that includes numerous metabolic genes, such as those associated with amino acid synthesis and sugar manipulation. Surprisingly, few of these presumably host-derived genes are shared with M. pusilla , but rather have their closest non-viral homologue in bacteria and other eukaryotes, indicating horizontal gene transfer. A comparative analysis of full-length DNA polymerase (DNApol) genes from prasinoviruses with their overall gene content, demonstrated that the phylogeny of DNApol gene fragments reflects the gene content of the viruses; hence, environmental DNApol gene sequences from prasinoviruses can be used to infer their overall genetic repertoire. Thus, the distribution of virus ecotypes across environmental samples based on DNApol sequences implies substantial underlying differences in gene content that reflect local environmental conditions. Moreover, the high diversity observed in the genetic repertoire of prasinoviruses has been driven by horizontal gene transfer throughout their evolutionary history, resulting in a broad suite of functional capabilities and a high diversity of prasinovirus ecotypes.

  5. Distribution Pattern of Healthcare Facilities in Osun State, Nigeria ...

    African Journals Online (AJOL)

    Distribution Pattern of Healthcare Facilities in Osun State, Nigeria. ... Ethiopian Journal of Environmental Studies and Management ... Accessibility to healthcare facilities has generally been identified as a major indicator of development, and the existing spatial pattern of distribution of healthcare facilities play very prominent ...

  6. ALADINA - an unmanned research aircraft for observing vertical and horizontal distributions of ultrafine particles within the atmospheric boundary layer

    Science.gov (United States)

    Altstädter, B.; Platis, A.; Wehner, B.; Scholtz, A.; Wildmann, N.; Hermann, M.; Käthner, R.; Baars, H.; Bange, J.; Lampert, A.

    2015-04-01

    This paper presents the unmanned research aircraft Carolo P360 "ALADINA" (Application of Light-weight Aircraft for Detecting IN situ Aerosol) for investigating the horizontal and vertical distribution of ultrafine particles in the atmospheric boundary layer (ABL). It has a wingspan of 3.6 m, a maximum take-off weight of 25 kg and is equipped with aerosol instrumentation and meteorological sensors. A first application of the system, together with the unmanned research aircraft MASC (Multi-Purpose Airborne Carrier) of the Eberhard Karls University of Tübingen (EKUT), is described. As small payload for ALADINA, two condensation particle counters (CPC) and one optical particle counter (OPC) were miniaturised by re-arranging the vital parts and composing them in a space-saving way in the front compartment of the airframe. The CPCs are improved concerning the lower detection threshold and the response time to less than 1.3 s. Each system was characterised in the laboratory and calibrated with test aerosols. The CPCs are operated in this study with two different lower detection threshold diameters of 11 and 18 nm. The amount of ultrafine particles, which is an indicator for new particle formation, is derived from the difference in number concentrations of the two CPCs (ΔN). Turbulence and thermodynamic structure of the boundary layer are described by measurements of fast meteorological sensors that are mounted at the aircraft nose. A first demonstration of ALADINA and a feasibility study were conducted in Melpitz near Leipzig, Germany, at the Global Atmosphere Watch (GAW) station of the Leibniz Institute for Tropospheric Research (TROPOS) on 2 days in October 2013. There, various ground-based instruments are installed for long-term atmospheric monitoring. The ground-based infrastructure provides valuable additional background information to embed the flights in the continuous atmospheric context and is used for validation of the airborne results. The development of the

  7. Experimental investigation of heat transfer and flow pattern from heated horizontal rectangular fin array under natural convection

    Science.gov (United States)

    Taji, S. G.; Parishwad, G. V.; Sane, N. K.

    2014-07-01

    This paper presents results of the experimental study conducted on heated horizontal rectangular fin array under natural convection. The temperature mapping and the prediction of the flow patterns over the fin array with variable fin spacing is carried out. Dimensionless fin spacing to height (S/H) ratio is varied from 0.05 to 0.3 and length to height ratio (L/H) = 5 is kept constant. The heater input to the fin array assembly is varied from 25 to 100 W. The single chimney flow pattern is observed from 8 to 12 mm fin spacing. The end flow is choked below 6 mm fin spacing. The single chimney flow pattern changes to sliding or end flow choking at 6 mm fin spacing. The average heat transfer coefficient (ha) is very small (2.52-5.78 W/m2 K) at 100 W for S = 5-12 mm. The ha is very small (1.12-1.8 W/m2 K) at 100 W for 2-4 mm fin spacing due to choked fin array end condition. The end flow is not sufficient to reach up to central portion of fin array and in the middle portion there is an unsteady down and up flow pattern resulting in sliding chimney. The central bottom portion of fin array channel does not contribute much in heat dissipation for S = 2-4 mm. The ha has significantly improved at higher spacing as compared to lower spacing region. The single chimney flow pattern is preferred from heat transfer point of view. The optimum spacing is confirmed in the range of 8-10 mm. The average heat transfer results are compared with previous literature and showed similar trend and satisfactory agreement. An empirical equation has been proposed to correlate the average Nusselt number as a function of Grashof number and fin spacing to height ratio. The average error for this equation is -0.32 %.

  8. Distribution and antibiotic susceptibility pattern of methicillin ...

    African Journals Online (AJOL)

    Background: The rise of methicillin resistant Staphylococcus aureus (MRSA) infection has become a serious health issue. The emergence of mutidrug – resistant MRSA strains compounds chemotherapy and has raised public health concern. In this preliminary study, the distribution and antimicrobial susceptibility profile of ...

  9. Vegetation community structure, composition and distribution pattern ...

    African Journals Online (AJOL)

    There was no significant difference in species diversity between sampling areas, which had a Shannon's diversity index ranging from 1.64 to 2.63. ... We conclude that habitat characteristics, fire, past and the present exploitation clearly influence the species diversity, distribution and variation in vegetation communities.

  10. Horizontal and vertical distribution of lignin in surface sediments of the Gdansk Basin

    Directory of Open Access Journals (Sweden)

    Andrzej Staniszewski

    2001-12-01

    Full Text Available The aim of this study was to identify and quantify lignin transported from the River Vistula to the accumulation area in the Gdansk Basin. Sediment samples collected along the Vistula mouth - Gdansk Deep transect were analysed for lignin. Lignin was characterised by oxidative degradation, cupric oxide being chosen as the most suitable oxidising agent. The polar functional groups of the oxidation products were silylated and the derivatives analysed by capillary gas chromatography on fused capillary silica columns with flame ionisation detection. Lignin-derived oxidation products were quantified in the range from 3 to 20 µg g-1 dry wt. for phenolic acids and from 6 to 12 µg g-1 dry wt. for phenolic aldehydes. Differences in oxidation products contents are assigned to different lignin sources in the marine environment. The horizontal and vertical gradients of these compounds in the sediments of the Gdansk Basin are documented. The results are discussed in terms of the origin and fate of organic matter in the Gdansk Basin. The measured differences in quality and quantity of the identified oxidation products provide insight into diagenetic processes in the surface marine sediments.

  11. Development of Spatial Distribution Patterns by Biofilm Cells

    DEFF Research Database (Denmark)

    Haagensen, Janus Anders Juul; Hansen, Susse Kirkelund; Bak Christensen, Bjarke

    2015-01-01

    Confined spatial patterns of microbial distribution are prevalent in nature, such as in microbial mats, soil communities, and water stream biofilms. The symbiotic two-species consortium of Pseudomonas putida and Acinetobacter sp. C6, originally isolated from a creosote-polluted aquifer, has evolved...... in the context of species distribution patterns observed in macroecology, and we summarize observations about the processes involved in co-adaptation between P. putida and Acinetobacter sp. C6. Our results contribute to an understanding of spatial species distribution patterns as they are observed in nature...

  12. Flow patterns and pressure drop in air/water two-phase flow in horizontal helicoidal pipes

    Energy Technology Data Exchange (ETDEWEB)

    Awwad, A.; Xin, R.C.; Dong, Z.F.; Ebadian, M.A. [Florida International Univ., Miami, FL (United States). Dept. of Mechanical Engineering; Soliman, H.M. [Univ. of Manitoba, Winnipeg, Manitoba (Canada). Dept. of Mechanical Engineering

    1995-12-01

    An experimental investigation is conducted for air/water two-phase flow in horizontal helicoidal pipes. The helicoidal pipes are constructed of 25.4 mm I.D. Tygon tubing wrapped around cylindrical concrete forms with outside diameters of 62 cm and 124 cm. The helix angles of the helicoidal pipes vary from 1 to 20 deg. The experiments are performed for superficial water velocity in a range of U{sub L} = 0.008 {approximately} 2.2 m/s and for superficial air velocity in a range of U{sub G} = 0.2 {approximately} 50 m/s. The flow patterns are discerned and recorded photographically. The pressure drop of the air/water two-phase flow in the coils is measured and the Lockhart-Martinelli approach is used to analyze the data. The results are presented in the form of frictional pressure drop multipliers versus the Lockhart-Martinelli parameter. It was found that the flow patterns differ greatly from those of the straight pipe, and that the frictional pressure drop multipliers depend on both the Lockhart-Martinelli parameter and the flow rates. The correlation of the frictional pressure drop has been provided based on the current data. Furthermore, it was also found that the helix angle of the helicoidal pipe had almost no effect on the air/water two-phase flow pressure drop in the present experimental ranges.

  13. Effects of complex hydrodynamic processes on the horizontal and vertical distribution of Tc-99 in the Irish Sea

    Energy Technology Data Exchange (ETDEWEB)

    Olbert, Agnieszka I., E-mail: indiana.olbert@nuigalway.ie [Civil Engineering Department, Environmental Change Institute, National University of Ireland, Galway (Ireland); Hartnett, Michael; Dabrowski, Tomasz [Civil Engineering Department, Environmental Change Institute, National University of Ireland, Galway (Ireland); Kelleher, Kevin [Radiological Protection Institute of Ireland, 3 Clonskeagh Square, Clonskeagh Road, Dublin 14 (Ireland)

    2010-12-01

    The increased discharge of Tc-99 from the Sellafield plant following the commissioning of the Enhance Actinide Removal Plant in 1994 was reflected in higher Tc-99 activity concentrations over much of the Irish Sea. The presence of this radionuclide in the marine environment is of concern not only because of its long half life but also high bio-concentration factor in commercially valuable species, such Norway lobster (Nephrops norvegicus) and common lobster (Homarus gammarus). Accurate predictions of the transport, and spatial and temporal distributions of Tc-99 in the Irish Sea have important environmental and commercial implications. In this study, transport of the Tc-99 material was simulated in order to develop an increased understanding of long-term horizontal and vertical distributions. In particular, impact of seasonal hydrodynamic features such as the summer stratification on the surface-to-bottom Tc-99 ratio was of interest. Also, material retention mechanisms within the western Irish Sea were explored and flushing rates under various release conditions and meteorological forcing were estimated. The results show that highest vertical gradients are observed between June and July in the deepest regions of the North Channel and the western Irish Sea where radionuclide-rich saline-poor water overlays radionuclide-poor saline-rich Atlantic water masses. Strong correlation between top-to-bottom ratio of Tc-99 and strength of stratification was found. Flushing studies demonstrate that as the stratification intensifies, residence times within the western Irish Sea increase. In stratified waters of the gyre Tc-99 material is flushed out from the upper layer much quicker than from the bottom zone. The research also shows that in the gyre the biologically active upper layers above the thermocline are likely to contain higher concentrations than the near-bed region. Long-term horizontal and vertical distributions as determined in this study provide a basis for

  14. EXPERIMENTAL STUDY OF HORIZONTAL PRESSURE DISTRIBUTION ON CORRUGATED STEEL SILO WALLS

    Directory of Open Access Journals (Sweden)

    V. V. Kachurenko

    2016-08-01

    Full Text Available Purpose. The paper aims: 1 qualitative assessment of the nature of the container corrugated wall deformation caused by the load from bulk materials. 2 determination of the horizontal pressure redistribution scheme for each individual corrugation plate and the calculation method that is closer to the real situation. 3 obtaining the quantitativedeformation indicators to compare them with the calculated ones produced by means of mathematical model simulation. Methodology.To achieve this purpose the different types of capacitive structure profiles were investigated and the values of total vertical displacement under load were obtained. The computational experiment used the design computer system Structure CAD for Windows. In addition, the laboratory experiment was conducted, the analysis of which is important to confirm the correctness of pre-made computer models. Findings. The conducted experiment allowed receiving the confirmation of the FEM calculated data, namely qualitatively and quantitatively the deformation direction and nature completely repeated the design situation in SCAD. Thework ofcorrugatedprofile was analysedfordifferenttheoreticallypossibleload schemesanddifferentcalculation methods. Alsotheworkcontainstherecommendationsfortherealcalculationusingcomputersimulation. During a joint study the authors obtained the data that allow for more accurate assessment of the corrugated profile performance under the pressure from bulk materials. Originality. The conducted research and experimental tests explain and clarify the ways for possible redistribution of bulk material pressure on each corrugation plate, while there is no such information in the existing recommendation literature and regulatory framework concerning the capacitive structure design. Practical value.The use of the proposed solutions is useful for correct design of containers with corrugated walls during further calculations and search of new directions for future research.

  15. Comparison of surgically induced astigmatism between horizontal and X-pattern sutures in the scleral tunnel incisions for manual small incision cataract surgery.

    Science.gov (United States)

    Eslami, Yadollah; Mirmohammadsadeghi, Arash

    2015-07-01

    Two types of popular scleral tunnel sutures in the manual small incision cataract surgery (MSICS) are horizontal and X-pattern sutures. Surgically induced corneal astigmatism (SIA) is a useful indicator of the suturing effect. To compare SIA between horizontal and X-pattern sutures in the scleral tunnel incisions for MSICS. Prospective, nonrandomized comparative trial. After superior scleral tunnel incision and capsulorhexis, the nucleus was prolapsed into the anterior chamber and delivered. The wound was sutured with either horizontal or X-pattern suture. The simulated keratometry values were derived from the corneal topography preoperatively and 1.5 and 3 months postoperatively. The SIA was calculated by Cartesian coordinates based analysis. Sixty-four patients (32 patients in each group) were included in the study. In the horizontal suture group, the SIA centroid values at 1.5 and 3 months after the surgery were 0.87 × 1° and 1.11 × 180°, respectively, showing induction of against-the-rule astigmatism. In the X-pattern suture group, the SIA centroid values at 1.5 and 3 months after the surgery were 0.61 × 97° and 0.66 × 92°, respectively, showing induction of mild with-the-rule astigmatism. The difference between the amount of SIA at 1.5 and 3 months after surgery was small. In the MSICS, the X-pattern sutures were preferred to the horizontal sutures in the patients without significant preoperative steepening in line with the central meridian of the incision. In the cases with significant preoperative steepening, sutureless surgery or horizontal sutures were preferred. Corneal astigmatism in the patients undergoing MSICS was stable at 1.5 months after the surgery.

  16. Comparison of surgically induced astigmatism between horizontal and X-pattern sutures in the scleral tunnel incisions for manual small incision cataract surgery

    Directory of Open Access Journals (Sweden)

    Yadollah Eslami

    2015-01-01

    Full Text Available Background: Two types of popular scleral tunnel sutures in the manual small incision cataract surgery (MSICS are horizontal and X-pattern sutures. Surgically induced corneal astigmatism (SIA is a useful indicator of the suturing effect. Aims: To compare SIA between horizontal and X-pattern sutures in the scleral tunnel incisions for MSICS. Design: Prospective, nonrandomized comparative trial. Materials and Methods: After superior scleral tunnel incision and capsulorhexis, the nucleus was prolapsed into the anterior chamber and delivered. The wound was sutured with either horizontal or X-pattern suture. The simulated keratometry values were derived from the corneal topography preoperatively and 1.5 and 3 months postoperatively. Statistical Analysis: The SIA was calculated by Cartesian coordinates based analysis. Results: Sixty-four patients (32 patients in each group were included in the study. In the horizontal suture group, the SIA centroid values at 1.5 and 3 months after the surgery were 0.87 × 1° and 1.11 × 180°, respectively, showing induction of against-the-rule astigmatism. In the X-pattern suture group, the SIA centroid values at 1.5 and 3 months after the surgery were 0.61 × 97° and 0.66 × 92°, respectively, showing induction of mild with-the-rule astigmatism. The difference between the amount of SIA at 1.5 and 3 months after surgery was small. Conclusion: In the MSICS, the X-pattern sutures were preferred to the horizontal sutures in the patients without significant preoperative steepening in line with the central meridian of the incision. In the cases with significant preoperative steepening, sutureless surgery or horizontal sutures were preferred. Corneal astigmatism in the patients undergoing MSICS was stable at 1.5 months after the surgery.

  17. Estimating the Distribution of Dietary Consumption Patterns

    KAUST Repository

    Carroll, Raymond J.

    2014-02-01

    In the United States the preferred method of obtaining dietary intake data is the 24-hour dietary recall, yet the measure of most interest is usual or long-term average daily intake, which is impossible to measure. Thus, usual dietary intake is assessed with considerable measurement error. We were interested in estimating the population distribution of the Healthy Eating Index-2005 (HEI-2005), a multi-component dietary quality index involving ratios of interrelated dietary components to energy, among children aged 2-8 in the United States, using a national survey and incorporating survey weights. We developed a highly nonlinear, multivariate zero-inflated data model with measurement error to address this question. Standard nonlinear mixed model software such as SAS NLMIXED cannot handle this problem. We found that taking a Bayesian approach, and using MCMC, resolved the computational issues and doing so enabled us to provide a realistic distribution estimate for the HEI-2005 total score. While our computation and thinking in solving this problem was Bayesian, we relied on the well-known close relationship between Bayesian posterior means and maximum likelihood, the latter not computationally feasible, and thus were able to develop standard errors using balanced repeated replication, a survey-sampling approach.

  18. Patterns of bird and mammal distribution in Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The present distributional patterns of birds and mammals on the surface of the earth are the combined result of historic and current factors. The historic factors...

  19. The impact of fracking on freight distribution patterns.

    Science.gov (United States)

    2016-11-01

    The increasing production of domestic energy through the use of fracking will likely alter local/regional/national economies and corresponding freight distribution patterns (highway, rail, marine, pipeline) in the United States. The proposed project ...

  20. Horizontal projections of area 17 in Cebus monkeys: metric features, and modular and laminar distribution

    Directory of Open Access Journals (Sweden)

    A.K.J. Amorim

    1997-12-01

    Full Text Available Metric features and modular and laminar distributions of intrinsic projections of area 17 were studied in Cebus apella. Anterogradely and retrogradely labeled cell appendages were obtained using both saturated pellets and iontophoretic injections of biocytin into the operculum. Laminar and modular distributions of the labeled processes were analyzed using Nissl counterstaining, and/or cytochrome oxidase and/or NADPH-diaphorase histochemistry. We distinguished three labeled cell types: pyramidal, star pyramidal and stellate cells located in supragranular cortical layers (principally in layers IIIa, IIIb a, IIIb ß and IIIc. Three distinct axon terminal morphologies were found, i.e., Ia, Ib and II located in granular and supragranular layers. Both complete and partial segregation of group I axon terminals relative to the limits of the blobs of V1 were found. The results are compatible with recent evidence of incomplete segregation of visual information flow in V1 of Old and New World primates

  1. Vertical and horizontal distribution of magnetic susceptibility and metal contents in an industrial district of central Iran

    Science.gov (United States)

    Naimi, Salman; Ayoubi, Shamsollah

    2013-09-01

    This study was conducted to determine the vertical and horizontal distribution of selected metals and magnetic susceptibility (χlf) in an industrial site located in Isfahan province, central Iran. For this purpose, we used a grid sampling methodology and excavated 202 profiles. Soil samples were then collected from 0-30, 60-90, and 120-150 cm depths. The mass magnetic susceptibility (χ) of the soil samples was measured at both low and high frequencies (χlf and χhf) using the Bartington MS2 dual frequency sensor; and χfd was also calculated. Soil samples were also analyzed for iron (Fe), manganese (Mn), lead (Pb), zinc (Zn), copper (Cu), nickel (Ni), chromium (Cr) and cobalt (Co) concentrations. The results showed that there were positive significant correlations among selected metals including Zn, Pb, Fe and Mn, which were mainly added through coal fly ash from an iron smelting factory at the studied site, while the concentration of Ni, Cr and Co was mainly controlled by the parent material of the soils. The trends in results at the site of study were similar in vertical and horizontal distribution for the industrial originated metals as judged by pollution load index (PLI) using χlf. The results of SEM/EDX also confirmed the presence of spheroid of magnetic particles in the surface soil samples taken in close proximity of the factory. Based on the results using the contamination factors (CF) determined for selected metals, the following order was observed: Pb > Zn > Mn > Fe > Cu > Ni ≥ Co > Cr. The results also suggested that magnetic methods could be used to estimate the metal contamination from anthropogenic sources in industrial soils.

  2. Intermodal transport and distribution patterns in ports relationship to hinterland

    Science.gov (United States)

    Dinu, O.; Dragu, V.; Ruscă, F.; Ilie, A.; Oprea, C.

    2017-08-01

    It is of great importance to examine all interactions between ports, terminals, intermodal transport and logistic actors of distribution channels, as their optimization can lead to operational improvement. Proposed paper starts with a brief overview of different goods types and allocation of their logistic costs, with emphasis on storage component. Present trend is to optimize storage costs by means of port storage area buffer function, by making the best use of free storage time available, most of the ports offer. As a research methodology, starting point is to consider the cost structure of a generic intermodal transport (storage, handling and transport costs) and to link this to intermodal distribution patterns most frequently cast-off in port relationship to hinterland. The next step is to evaluate storage costs impact on distribution pattern selection. For a given value of port free storage time, a corresponding value of total storage time in the distribution channel can be identified, in order to substantiate a distribution pattern shift. Different scenarios for transport and handling costs variation, recorded when distribution pattern shift, are integrated in order to establish the reaction of the actors involved in port related logistic and intermodal transport costs evolution is analysed in order to optimize distribution pattern selection.

  3. Patterns in exoplanet count and eccentricity distributions

    Science.gov (United States)

    Taylor, Stuart F.

    2018-01-01

    The distribution of exoplanets of contains an unexpected level of features, starting with an unexpected gap the splits the main pileup of much of the planet population. In the population of planets of metal-rich sunlike single stars (SLSS objects), which comprises 40% of planets found by the radial velocity method, when counting logarithmic periods the main pileup of planets with periods longer than 100 days is split into two peaks separated by a significant gap. There is a wide region which has so few planets that none are found in the current data set. We show that this gap is extremely unlikely to occur by random. Because this gap is well-filled among planets of low surface gravity and low metallicity stars with 31 objects, it is unlikely that the bimodal nature of the metal rich SLSS population is due to observational effects. Comparisons of eccentricity of the metal-rich and metal-poor SLSS populations depend strongly on the two-peak-gap structure of counts of the metal-rich SLSS (rSLSS) population. Consideration of these features is essential to properly study the correlations of eccentricity with other planet-system parameters given how the eccentricity of rSLSS objects is highest in the two peaks of the rSLSS population.

  4. Distribution pattern of histone H3 phosphorylation at serine 10 ...

    Indian Academy of Sciences (India)

    2013-08-06

    Aug 6, 2013 ... in chromosome distribution of H3S10ph when mitosis and meiosis were compared. ... [Paula C. M. P., Techio V. H., Sobrinho F. S. and Freitas A. S. 2013 Distribution pattern of histone H3 phosphorylation at serine 10 during mitosis and meiosis in ... RDWebster], since current knowledge about specific roles ...

  5. Distribution Pattern of Healthcare Facilities in Osun State, Nigeria ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    existing spatial pattern of distribution of healthcare facilities play very prominent role in gauging the level of efficiency or otherwise of the existing level of ... 1998). In investigating the level of provision of central facilities (like healthcare), emphasis .... It is important to note that other statistical measure of spatial distribution of ...

  6. Zoogeographical Patterns in the Distribution of East African ...

    African Journals Online (AJOL)

    The savanna fauna of treefrogs in East Africa includes five distributional patterns: a widely distributed element, an element in the savanna north of the central forest from Cameroun to northern East Africa. an element south of the central forest, an East African lowland fauna. and an element in the dry savanna of Kenya and ...

  7. Assessment of the horizontal, fore-aft component of the ground reaction force from insole pressure patterns by using artificial neural networks

    NARCIS (Netherlands)

    Dr Hans C.C.M. Savelberg; Dr. ir. A. de Lange

    1999-01-01

    Objective. In this study it was investigated whether an artificial neural network can be used to determine the horizontal, fore-aft component of the ground reaction force from insole pressure patterns. Design. An artificial neural network was applied to map insole pressures and ground reaction

  8. Diffuse scarring alopecia in a female pattern hair loss distribution.

    Science.gov (United States)

    Fergie, Bonnie; Khaira, Gurpreet; Howard, Vicki; de Zwaan, Sally

    2017-02-17

    We describe three cases of hair loss in a female pattern hair loss (FPHL) distribution with histologic features of lichen planopilaris (LPP). All patients had a history of diffuse, gradual hair loss in a Christmas tree pattern that clinically presented as FPHL on gross and dermoscopic examination. Notably, there were no characteristic clinical signs of LPP and no histologic features of FPHL. These cases are most consistent with cicatricial pattern hair loss (CPHL). This relatively new entity is similar to fibrosing alopecia in a pattern distribution (FAPD) in that they are both scarring alopecias confined to a FPHL distribution, but CPHL lacks the clinical signs of perifollicular erythema and perifollicular keratosis seen in FAPD. These three cases may present an early, subtle form of CPHL and will be of interest to clinicians and histopathologists alike. © 2017 The Australasian College of Dermatologists.

  9. Horizontal distributions of biogenic and lithogenic elements of suspended particulate matter in the Mediterranean Sea

    Science.gov (United States)

    Price, N. B.; Brand, T.; Pates, J. M.; Mowbray, S.; Theocharis, A.; Civitarese, G.; Miserocchi, S.; Heussner, S.; Lindsay, F.

    1999-08-01

    A study has been made of the distribution of terrigenous (Al and Mn ex, Fe ex) and biogenic (POC, PN tot, P org, Si bio, Ba ex) elements of suspended particulate matter (SPM) on a series of transects in three marginal areas of the Mediterranean Sea; the NW Mediterranean, the western Adriatic to the Strait of Otranto and the southern (Cretan) and northern Aegean Sea, with the intention of assessing the influence that river discharges have on their concentrations. In the Adriatic, high Al concentrations (60-200 μgl -1) occur as a consequence of direct discharge from the River Po but importantly from sediment resuspension the amount of which, under steady state conditions, is also related to riverine discharge. In the Otranto Strait high Al concentrations overlie its western shelf and slope. On the NW Mediterranean only waters influenced by the River Rhone, as off Banyuls-sur-mer, show high Al. Particulate Mn is mostly river derived, but principally exists in marginal areas from redox cycling in surficial sediments, a consequence of high biological production induced by nutrient discharges from rivers. High particulate Mn ex concentrations were measured in the northern Adriatic, off Banyuls-sur-mer and the northern Aegean, where there are strong river influences. In contrast, the more oligotrophic seawaters off Marseilles, the Balearics and the Cretan Sea show lower concentrations of Mn ex, and depth profiles of Mn ex especially in the latter area are similar to those found in ocean waters. Of the biogenic elements studied, the assumed presence of terrigenous organic carbon, especially on the Adriatic shelf, largely precludes POC concentrations from being an indicator of marine production. A better guide to productivity induced by river nutrient discharges is seen in the distribution of P org and Si bio concentrations, which show a gradual southward reduction along the Adriatic shelf and higher concentrations off Banyuls-sur-mer than on other transects in the NW

  10. The distribution of near point of convergence, near horizontal heterophoria, and near vergence among myopic children in South Korea.

    Science.gov (United States)

    Jang, Jung Un; Park, Inn-Jee; Jang, Jung Yun

    2016-01-01

    To assess the distribution of near point of convergence (NPC), near heterophoria, and near vergence among myopic school children in South Korea. One hundred and thirty-six elementary school children, aged 8-13 years, were each given a thorough eye examination including binocular vision testing, NPC using standard push-up technique, horizontal heterophoria measurement by Von Graefe, distance, and near negative and positive vergence with a phoropter and phoropter replacement card. NPC break and recovery points were highest in the age 9 years group, but the mean values of NPC were within the normal range. Of 136 individuals, 52 presented with esophoria, 53 presented with 0 -6-Δ exophoria, and 31 presented with ≥7-Δ exophoria. In the younger age groups (8 years and 10 years) 0-6-Δ exophoria was prevalent, whereas in the older age groups (11 years, 12 years, and 13 years) esophoria was prevalent. Near positive fusional vergence (break and recovery point) presented with statistically significant correlations with the participants' ages. Esophoria showed higher correlations with high myopia (8.00 ± 0.000) rather than with low myopia (3.36 ± 2.499) or medium myopia (3.42 ± 2.149). The mean value of 0-6Δ exophoria was highest in medium myopia (4.04 ± 1.517), and of ≥7-Δ exophoria was the highest in high myopia (12.66 ± 1.154). There were no statistically significant correlations between the school childrens' ages and NPC, near horizontal heterophoria, and near fusional vergence, except near positive fusional vergence. Also, unlike many studies, myopic magnitude did not present a significant correlation with near phoria and fusional vergence.

  11. Relationships between dendritic morphology, spatial distribution and firing patterns in rat layer 1 neurons

    Directory of Open Access Journals (Sweden)

    D.V.V. Santos

    2012-12-01

    Full Text Available The cortical layer 1 contains mainly small interneurons, which have traditionally been classified according to their axonal morphology. The dendritic morphology of these cells, however, has received little attention and remains ill defined. Very little is known about how the dendritic morphology and spatial distribution of these cells may relate to functional neuronal properties. We used biocytin labeling and whole cell patch clamp recordings, associated with digital reconstruction and quantitative morphological analysis, to assess correlations between dendritic morphology, spatial distribution and membrane properties of rat layer 1 neurons. A total of 106 cells were recorded, labeled and subjected to morphological analysis. Based on the quantitative patterns of their dendritic arbor, cells were divided into four major morphotypes: horizontal, radial, ascendant, and descendant cells. Descendant cells exhibited a highly distinct spatial distribution in relation to other morphotypes, suggesting that they may have a distinct function in these cortical circuits. A significant difference was also found in the distribution of firing patterns between each morphotype and between the neuronal populations of each sublayer. Passive membrane properties were, however, statistically homogeneous among all subgroups. We speculate that the differences observed in active membrane properties might be related to differences in the synaptic input of specific types of afferent fibers and to differences in the computational roles of each morphotype in layer 1 circuits. Our findings provide new insights into dendritic morphology and neuronal spatial distribution in layer 1 circuits, indicating that variations in these properties may be correlated with distinct physiological functions.

  12. The influence of vegetation on the horizontal and vertical distribution of pollutants in a street canyon.

    Science.gov (United States)

    Salmond, J A; Williams, D E; Laing, G; Kingham, S; Dirks, K; Longley, I; Henshaw, G S

    2013-01-15

    Space constraints in cities mean that there are only limited opportunities for increasing tree density within existing urban fabric and it is unclear whether the net effect of increased vegetation in street canyons is beneficial or detrimental to urban air quality at local scales. This paper presents data from a field study undertaken in Auckland, New Zealand designed to determine the local impact of a deciduous tree canopy on the distribution of the oxides of nitrogen within a street canyon. The results showed that the presence of leaves on the trees had a marked impact on the transport of pollutants and led to a net accumulation of pollutants in the canyon below the tree tops. The incidence and magnitude of temporally localised spikes in pollutant concentration were reduced within the tree canopy itself. A significant difference in pollutant concentrations with height was not observed when leaves were absent. Analysis of the trends in concentration associated with different wind directions showed a smaller difference between windward and leeward sides when leaves were on the trees. A small relative increase in concentrations on the leeward side was observed during leaf-on relative to leaf-off conditions as predicted by previous modelling studies. However the expected reduction in concentrations on the windward side was not observed. The results suggest that the presence of leaves on the trees reduces the upwards transport of fresh vehicle emissions, increases the storage of pollutants within the canopy space and reduces the penetration of clean air downwards from aloft. Differences observed between NO and NO(2) concentrations could not be accounted for by dispersion processes alone, suggesting that there may also be some changes in the chemistry of the atmosphere associated with the presence of leaves on the trees. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Coralligenous habitat: patterns of vertical distribution of macroalgal assemblages

    Directory of Open Access Journals (Sweden)

    Luigi Piazzi

    2011-06-01

    Full Text Available The present study investigates patterns of distribution of macroalgal coralligenous assemblages in relation to depth and evaluates the role of different environmental conditions on these patterns. Two depths (30 and 40 m were investigated off small islands and off continental coasts in order to select two different environmental conditions. Results showed differences between depths in the structure of assemblages around islands, while along the continental coasts these patterns were not evident. Moreover, differences between assemblages related to different environmental conditions were more evident in the shallower zone of distribution of the coralligenous habitat. This correlative study did not allow us to identify any cause-effect relationship, but patterns we detected agree with those of other studies, suggesting that alterations in the environmental conditions may be the cause of the decrease in differences among assemblages developing at different depths and may lead to a higher spatial homogenization and an impoverishment of the whole subtidal system.

  14. Large scale patterns in vertical distribution and behaviour of mesopelagic scattering layers

    KAUST Repository

    Klevjer, Thor Aleksander

    2016-01-27

    Recent studies suggest that previous estimates of mesopelagic biomasses are severely biased, with the new, higher estimates underlining the need to unveil behaviourally mediated coupling between shallow and deep ocean habitats. We analysed vertical distribution and diel vertical migration (DVM) of mesopelagic acoustic scattering layers (SLs) recorded at 38 kHz across oceanographic regimes encountered during the circumglobal Malaspina expedition. Mesopelagic SLs were observed in all areas covered, but vertical distributions and DVM patterns varied markedly. The distribution of mesopelagic backscatter was deepest in the southern Indian Ocean (weighted mean daytime depth: WMD 590 m) and shallowest at the oxygen minimum zone in the eastern Pacific (WMD 350 m). DVM was evident in all areas covered, on average ~50% of mesopelagic backscatter made daily excursions from mesopelagic depths to shallow waters. There were marked differences in migrating proportions between the regions, ranging from ~20% in the Indian Ocean to ~90% in the Eastern Pacific. Overall the data suggest strong spatial gradients in mesopelagic DVM patterns, with implied ecological and biogeochemical consequences. Our results suggest that parts of this spatial variability can be explained by horizontal patterns in physical-chemical properties of water masses, such as oxygen, temperature and turbidity.

  15. Molecular variation and horizontal gene transfer of the homocysteine methyltransferase gene mmuM and its distribution in clinical pathogens.

    Science.gov (United States)

    Ying, Jianchao; Wang, Huifeng; Bao, Bokan; Zhang, Ying; Zhang, Jinfang; Zhang, Cheng; Li, Aifang; Lu, Junwan; Li, Peizhen; Ying, Jun; Liu, Qi; Xu, Teng; Yi, Huiguang; Li, Jinsong; Zhou, Li; Zhou, Tieli; Xu, Zuyuan; Ni, Liyan; Bao, Qiyu

    2015-01-01

    The homocysteine methyltransferase encoded by mmuM is widely distributed among microbial organisms. It is the key enzyme that catalyzes the last step in methionine biosynthesis and plays an important role in the metabolism process. It also enables the microbial organisms to tolerate high concentrations of selenium in the environment. In this research, 533 mmuM gene sequences covering 70 genera of the bacteria were selected from GenBank database. The distribution frequency of mmuM is different in the investigated genera of bacteria. The mapping results of 160 mmuM reference sequences showed that the mmuM genes were found in 7 species of pathogen genomes sequenced in this work. The polymerase chain reaction products of one mmuM genotype (NC_013951 as the reference) were sequenced and the sequencing results confirmed the mapping results. Furthermore, 144 representative sequences were chosen for phylogenetic analysis and some mmuM genes from totally different genera (such as the genes between Escherichia and Klebsiella and between Enterobacter and Kosakonia) shared closer phylogenetic relationship than those from the same genus. Comparative genomic analysis of the mmuM encoding regions on plasmids and bacterial chromosomes showed that pKF3-140 and pIP1206 plasmids shared a 21 kb homology region and a 4.9 kb fragment in this region was in fact originated from the Escherichia coli chromosome. These results further suggested that mmuM gene did go through the gene horizontal transfer among different species or genera of bacteria. High-throughput sequencing combined with comparative genomics analysis would explore distribution and dissemination of the mmuM gene among bacteria and its evolution at a molecular level.

  16. Distribution patterns and migratory behavior of Antarctic blue whales

    OpenAIRE

    Thomisch, Karolin

    2016-01-01

    After having been one of the primary targets of commercial whaling during the 20th century, Antarctic blue whales (Balaenoptera musculus intermedia) are still listed as critically endangered by the International Union for Conservation of Nature and many aspects of their distribution and migration patterns remain poorly understood to date. This dissertation investigates spatio-temporal patterns in the (acoustic) presence of Antarctic blue whales in the Atlantic sector of the Southern Ocean and...

  17. Surface-Wettability Patterning for Distributing High-Momentum Water Jets on Porous Polymeric Substrates.

    Science.gov (United States)

    Sen, Uddalok; Chatterjee, Souvick; Sinha Mahapatra, Pallab; Ganguly, Ranjan; Dodge, Richard; Yu, Lisha; Megaridis, Constantine M

    2018-02-07

    Liquid jet impingement on porous materials is particularly important in many applications of heat transfer, filtration, or in incontinence products. Generally, it is desired that the liquid not penetrate the substrate at or near the point of jet impact, but rather be distributed over a wider area before reaching the back side. A facile wettability-patterning technique is presented, whereby a water jet impinging orthogonally on a wettability-patterned nonwoven substrate is distributed on the top surface and through the porous matrix, and ultimately dispensed from prespecified points underneath the sample. A systematic approach is adopted to identify the optimum design that allows for a uniform distribution of the liquid on horizontally mounted substrates of ∼50 cm 2 area, with minimal or no spilling over the sample edges at jet flow rates exceeding 1 L/min. The effect of the location of jet impingement on liquid distribution is also studied, and the design is observed to perform well even under offset jet impact conditions.

  18. Thirteen years of Aeolian dust dynamics in a desert region (Negev desert, Israel): analysis of horizontal and vertical dust flux, vertical dust distribution and dust grain size

    NARCIS (Netherlands)

    Offer, Z.Y.; Goossens, D.

    2004-01-01

    At Sede Boqer (northern Negev desert, Israel), aeolian dust dynamics have been measured during the period 1988–2000. This study focuses on temporal records of the vertical and horizontal dust flux, the vertical distribution of the dust particles in the atmosphere, and the grain size of the

  19. Effect of different plant species on nutrient removal and rhizospheric microorganisms distribution in horizontal-flow constructed wetlands.

    Science.gov (United States)

    Meng, Panpan; Hu, Wenrong; Pei, Haiyan; Hou, Qingjie; Ji, Yan

    2014-01-01

    Three macrophyte species, Phragmites australis, Arundo donax L., and Typha latifolia L. have been separately grown in a horizontal-flow (HF) constructed wetland (CW) fed with domestic wastewater to investigate effects of plant species on nutrient removal and rhizospheric microorganisms. All the three mesocosms have been in operation for eight months under the loading rates of 1.14 g Nm(-2) d(-1) and 0.014gP m(-2) d(-1). Appropriately 34-43% phosphorus (P) was removed in HF CWs, and no distinct difference was found among the plants. In the growing season, A. donax L. removed 31.19 gm(-2) of nitrogen (N), followed by P. australis (29.96 g m(-2)), both of which were significantly higher than T. latifolia L. (7.21 g m(-2). Depending on the species, plants absorbed 1.73-7.15% of the overall N, and 0.06-0.56% of the P input. At least 10 common dominant microorganisms were found in the rhizosphere of all the three plants, and 6 of the 10 kinds of bacteria had close relationship with denitrifying bacteria, implying that denitrifiers were dominant microorganism distributed in rhizosphere of wetland plants.

  20. Combining Facility Location and Routing Decisions in Sustainable Urban Freight Distribution under Horizontal Collaboration: How Can Shippers Be Benefited?

    Directory of Open Access Journals (Sweden)

    Hanan Ouhader

    2017-01-01

    Full Text Available This article investigates the potential economic, environmental, and social effects of combining depot location and vehicle routing decisions in urban road freight transportation under horizontal collaboration. We consider a city in which several suppliers decide to joint deliveries to their customers and goods are delivered via intermediate depots. We study a transportation optimization problem from the perspective of sustainability development. This quantitative approach is based on three-objective mathematical model for strategic, tactical, and operational decision-making as a two-echelon location routing problem (2E-LRP. The objectives are to minimize cost and CO2 emissions of the transportation and maximize the created job opportunities. The model was solved with the ε-constraint method using extended known instances reflecting the real distribution in urban area to evaluate several goods’ delivery strategies. The obtained results by comparing collaborative and noncollaborative scenarios show that collaboration leads to a reduction in CO2 emissions, transportation cost, used vehicles, and travelled distances in addition to the improvement of the vehicles load rate but collaboration affects negatively social impact. To evaluate the effect of the method used to allocate the total gains to the different partners, we suggest to decision makers a comparison between well-known allocation methods.

  1. Normal plantar weight distribution pattern and its variations with ...

    African Journals Online (AJOL)

    Normal plantar weight distribution pattern and its variations with change of functional position and its comparison with patients of knee osteoarthritis. ... The participants in group-1 had no knee complaint and those in group-2 had diagnosis of early knee osteoarthritis. Independent test was used for the statistical analysis.

  2. Sparse Distribution Pattern Of Some Plant Species In Two ...

    African Journals Online (AJOL)

    This study analysed species diversity and distribution patterns on two afromontane rain forests of the eastern Arc Mountains of Tanzania in the west Usambaras and Ulugurus to assess any possible threats to biodiversity conservation in this region. A hundred sample plots (0.02 ha) were established on each of the two ...

  3. Photosynthate distribution patterns in cherrybark oak seedling sprouts

    Science.gov (United States)

    Brian Roy Lockhart; John D. Hodges; Emile S. Gardiner; Andrew W. Ezell

    2003-01-01

    Summary We used 14C tracers to determine photosynthate distribution in cherrybark oak (Quercus pagoda Raf.) seedling sprouts following release from competing mid-story vegetation. Fall acquisition of labeled photosynthates by seedlings followed expected source--sink patterns, with root and basal stem tissues...

  4. Heterogeneity of DNA Distribution Pattern in Renal Tumours

    Directory of Open Access Journals (Sweden)

    Hans Nenning

    1997-01-01

    Full Text Available The presence of intratumoural heterogeneity in DNA distribution patterns has been accepted. However, most previous studies have not taken this fact into consideration. The value of DNA cytometry depends on its reproducibility. This could be influenced by heterogeneity failure. The aim of the present study is to evaluate intratumoural heterogeneity in renal cell cancer.

  5. Pattern and distribution of sexually transmitted diseases in Lagos ...

    African Journals Online (AJOL)

    This study was designed to investigate the pattern and distribution of sexually transmitted diseases. A total of 134 adult Subjects (89 women and 45 men) presenting with various signs and symptoms of lower genital tract infections were recruited for the study. Samples such as urine, urethral swab, high vaginal swab and/or ...

  6. Anomalous patterns of formation and distribution of the brachial ...

    African Journals Online (AJOL)

    block Background: Structural variations in the patterns of formation and distribution of the brachial plexus have drawn attentions both in anatomy and anaesthesia. Method: An observational study. Results: The brachial plexus was carefully inspected in both the right and left arms in 90 Nigerian cadavers, comprising of 74 ...

  7. Pattern Recognition for Reliability Assessment of Water Distribution Networks

    NARCIS (Netherlands)

    Trifunović, N.

    2012-01-01

    The study presented in this manuscript investigates the patterns that describe reliability of water distribution networks focusing to the node connectivity, energy balance, and economics of construction, operation and maintenance. A number of measures to evaluate the network resilience has been

  8. A Spatial Analysis of Population Distribution and Housing Patterns ...

    African Journals Online (AJOL)

    The paper examined the spatial patterns of population distribution andhousing in Abraka in Delta State of Nigeria. Population is a vital componentof development in any country including Nigeria. Housing is a physical andsocial necessity of life which holds a place of strategic importance indevelopment. However, the high ...

  9. spatial patterns of zooplankton distribution and abundance in ...

    African Journals Online (AJOL)

    nb

    §The writing of this paper was completed posthumously. ABSTRACT. Spatial patterns and ... consideration because of its changes in limnological conditions caused by nutrients inputs and ..... distribution significantly positively. Table 1: Variation of water quality parameters (mean ± standard error) measured during the study.

  10. Distribution Pattern of Healthcare Facilities in Osun State, Nigeria ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    that the new wave of democratization that started in the country in 1999 has succeeded in achieving a wider spread of healthcare facilities and personnel in the state, thus contributing to the quality of life of the citizenry, especially those in the rural areas. Though the observed pattern of distribution of healthcare facilities and.

  11. Inhomogeneity Based Characterization of Distribution Patterns on the Plasma Membrane.

    Directory of Open Access Journals (Sweden)

    Laura Paparelli

    2016-09-01

    Full Text Available Cell surface protein and lipid molecules are organized in various patterns: randomly, along gradients, or clustered when segregated into discrete micro- and nano-domains. Their distribution is tightly coupled to events such as polarization, endocytosis, and intracellular signaling, but challenging to quantify using traditional techniques. Here we present a novel approach to quantify the distribution of plasma membrane proteins and lipids. This approach describes spatial patterns in degrees of inhomogeneity and incorporates an intensity-based correction to analyze images with a wide range of resolutions; we have termed it Quantitative Analysis of the Spatial distributions in Images using Mosaic segmentation and Dual parameter Optimization in Histograms (QuASIMoDOH. We tested its applicability using simulated microscopy images and images acquired by widefield microscopy, total internal reflection microscopy, structured illumination microscopy, and photoactivated localization microscopy. We validated QuASIMoDOH, successfully quantifying the distribution of protein and lipid molecules detected with several labeling techniques, in different cell model systems. We also used this method to characterize the reorganization of cell surface lipids in response to disrupted endosomal trafficking and to detect dynamic changes in the global and local organization of epidermal growth factor receptors across the cell surface. Our findings demonstrate that QuASIMoDOH can be used to assess protein and lipid patterns, quantifying distribution changes and spatial reorganization at the cell surface. An ImageJ/Fiji plugin of this analysis tool is provided.

  12. Pressure Transient Analysis and Flux Distribution for Multistage Fractured Horizontal Wells in Triple-Porosity Reservoir Media with Consideration of Stress-Sensitivity Effect

    Directory of Open Access Journals (Sweden)

    Jingjing Guo

    2015-01-01

    Full Text Available Triple-porosity model is usually adopted to describe reservoirs with multiscaled pore spaces, including matrix pores, natural fractures, and vugs. Multiple fractures created by hydraulic fracturing can effectively improve the connectivity between existing natural fractures and thus increase well deliverability. However, little work has been done on pressure transient behavior of multistage fractured horizontal wells in triple-porosity reservoirs. Based on source/sink function method, this paper presents a triple-porosity model to investigate the transient pressure dynamics and flux distribution for multistage fractured horizontal wells in fractured-vuggy reservoirs with consideration of stress-dependent natural fracture permeability. The model is semianalytically solved by discretizing hydraulic fractures and Pedrosa’s transformation, perturbation theory, and integration transformation method. Type curves of transient pressure dynamics are generated, and flux distribution among hydraulic fractures for a fractured horizontal well with constant production rate is also discussed. Parametric study shows that major influential parameters on transient pressure responses are parameters pertinent to reservoir properties, interporosity mass transfer, and hydraulic fractures. Analysis of flux distribution indicates that flux density gradually increases from the horizontal wellbore to fracture tips, and the flux contribution of outermost fractures is higher than that of inner fractures. The model can also be extended to optimize hydraulic fracture parameters.

  13. Macroecological patterns in the distribution of marine phytoplankton

    DEFF Research Database (Denmark)

    Mousing, Erik Askov

    and community size structure at the global scale. The statistical approach applied indicated that different nutrients were, apparently, co-limiting the examined phytoplankton processes in different regions of the world’s oceans. It is also shown that there is a strong increase in both phytoplankton total...... for predicting future ocean function. This PhD thesis investigates and describes macroecological patterns in the distribution and diversity of marine phytoplankton. The primary focus has been to describe macroecological patterns in phytoplankton total biomass and community structure and relate these patterns...... are presented as five research chapters shaped as manuscripts. In Manuscript I, the macroecological patterns in phytoplankton community size structure were investigated in relation to temperature and inorganic nutrient concentrations. Although temperature has been shown to directly affect phytoplankton size...

  14. Distribution patterns and coincidence of sesamoid bones at metatarsophalangeal joints.

    Science.gov (United States)

    Sun, Tao; Zhao, Haitao; Wang, Lingxiang; Wu, Wenjuan; Hu, Wenhai

    2017-04-01

    Our aim was to identify the incidence and distribution of sesamoid bones plantar to the metatarsophalangeal (MTP) joints in adults, and to evaluate patterns of coincidence among these sesamoid bones. We conducted a retrospective review of 7949 plain radiographs obtained from patients evaluated for foot trauma or symptomology. Associations between the distributions of MTP sesamoid bones as well as the association of age, sex, and laterality with identified prevalence, distribution, and coincidence were evaluated using Spearman's correlation coefficient. Overall, 17,060 sesamoid bones were identified for 9005 MTP joints, with 16 distinctive distribution patterns. Among possible patterns, we identified a prevalence rate of complete absence of MTP sesamoid of 0.04 %, of a single sesamoid at the hallux of 89.08 % of radiographs; and of sesamoid at ≥2 MTP joints of 10.88 %. The presence of a sesamoid at the hallux was consistent, and was not correlated with the presence or absence of a sesamoid bone at one of the other MTP joints (P > 0.05). However, there was a positive correlation between the presence and absence of sesamoid bones at any two of the other four MTP joints (P joints with sesamoids (P < 0.001). Information from this study would assist clinicians in the diagnosis of patients presenting with pain and discomfort of the foot after trauma and overuse, as well as contribute a robust data set for research in forensic science and anthropology.

  15. Optimal pattern distributions in Rete-based production systems

    Science.gov (United States)

    Scott, Stephen L.

    1994-01-01

    Since its introduction into the AI community in the early 1980's, the Rete algorithm has been widely used. This algorithm has formed the basis for many AI tools, including NASA's CLIPS. One drawback of Rete-based implementation, however, is that the network structures used internally by the Rete algorithm make it sensitive to the arrangement of individual patterns within rules. Thus while rules may be more or less arbitrarily placed within source files, the distribution of individual patterns within these rules can significantly affect the overall system performance. Some heuristics have been proposed to optimize pattern placement, however, these suggestions can be conflicting. This paper describes a systematic effort to measure the effect of pattern distribution on production system performance. An overview of the Rete algorithm is presented to provide context. A description of the methods used to explore the pattern ordering problem area are presented, using internal production system metrics such as the number of partial matches, and coarse-grained operating system data such as memory usage and time. The results of this study should be of interest to those developing and optimizing software for Rete-based production systems.

  16. Diversity and distribution patterns in high southern latitude sponges.

    Directory of Open Access Journals (Sweden)

    Rachel V Downey

    Full Text Available Sponges play a key role in Antarctic marine benthic community structure and dynamics and are often a dominant component of many Southern Ocean benthic communities. Understanding the drivers of sponge distribution in Antarctica enables us to understand many of general benthic biodiversity patterns in the region. The sponges of the Antarctic and neighbouring oceanographic regions were assessed for species richness and biogeographic patterns using over 8,800 distribution records. Species-rich regions include the Antarctic Peninsula, South Shetland Islands, South Georgia, Eastern Weddell Sea, Kerguelen Plateau, Falkland Islands and north New Zealand. Sampling intensity varied greatly within the study area, with sampling hotspots found at the Antarctic Peninsula, South Georgia, north New Zealand and Tierra del Fuego, with limited sampling in the Bellingshausen and Amundsen seas in the Southern Ocean. In contrast to previous studies we found that eurybathy and circumpolar distributions are important but not dominant characteristics in Antarctic sponges. Overall Antarctic sponge species endemism is ∼43%, with a higher level for the class Hexactinellida (68%. Endemism levels are lower than previous estimates, but still indicate the importance of the Polar Front in isolating the Southern Ocean fauna. Nineteen distinct sponge distribution patterns were found, ranging from regional endemics to cosmopolitan species. A single, distinct Antarctic demosponge fauna is found to encompass all areas within the Polar Front, and the sub-Antarctic regions of the Kerguelen Plateau and Macquarie Island. Biogeographical analyses indicate stronger faunal links between Antarctica and South America, with little evidence of links between Antarctica and South Africa, Southern Australia or New Zealand. We conclude that the biogeographic and species distribution patterns observed are largely driven by the Antarctic Circumpolar Current and the timing of past continent

  17. Diversity and Distribution Patterns in High Southern Latitude Sponges

    Science.gov (United States)

    Downey, Rachel V.; Griffiths, Huw J.; Linse, Katrin; Janussen, Dorte

    2012-01-01

    Sponges play a key role in Antarctic marine benthic community structure and dynamics and are often a dominant component of many Southern Ocean benthic communities. Understanding the drivers of sponge distribution in Antarctica enables us to understand many of general benthic biodiversity patterns in the region. The sponges of the Antarctic and neighbouring oceanographic regions were assessed for species richness and biogeographic patterns using over 8,800 distribution records. Species-rich regions include the Antarctic Peninsula, South Shetland Islands, South Georgia, Eastern Weddell Sea, Kerguelen Plateau, Falkland Islands and north New Zealand. Sampling intensity varied greatly within the study area, with sampling hotspots found at the Antarctic Peninsula, South Georgia, north New Zealand and Tierra del Fuego, with limited sampling in the Bellingshausen and Amundsen seas in the Southern Ocean. In contrast to previous studies we found that eurybathy and circumpolar distributions are important but not dominant characteristics in Antarctic sponges. Overall Antarctic sponge species endemism is ∼43%, with a higher level for the class Hexactinellida (68%). Endemism levels are lower than previous estimates, but still indicate the importance of the Polar Front in isolating the Southern Ocean fauna. Nineteen distinct sponge distribution patterns were found, ranging from regional endemics to cosmopolitan species. A single, distinct Antarctic demosponge fauna is found to encompass all areas within the Polar Front, and the sub-Antarctic regions of the Kerguelen Plateau and Macquarie Island. Biogeographical analyses indicate stronger faunal links between Antarctica and South America, with little evidence of links between Antarctica and South Africa, Southern Australia or New Zealand. We conclude that the biogeographic and species distribution patterns observed are largely driven by the Antarctic Circumpolar Current and the timing of past continent connectivity. PMID

  18. Strand-biased Gene Distribution in Bacteria Is Related to both Horizontal Gene Transfer and Strand-biased Nucleotide Composition

    Science.gov (United States)

    Wu, Hao; Qu, Hongzhu; Wan, Ning; Zhang, Zhang; Hu, Songnian; Yu, Jun

    2012-01-01

    Although strand-biased gene distribution (SGD) was described some two decades ago, the underlying molecular mechanisms and their relationship remain elusive. Its facets include, but are not limited to, the degree of biases, the strand-preference of genes, and the influence of background nucleotide composition variations. Using a dataset composed of 364 non-redundant bacterial genomes, we sought to illustrate our current understanding of SGD. First, when we divided the collection of bacterial genomes into non-polC and polC groups according to their possession of DnaE isoforms that correlate closely with taxonomy, the SGD of the polC group stood out more significantly than that of the non-polC group. Second, when examining horizontal gene transfer, coupled with gene functional conservation (essentiality) and expressivity (level of expression), we realized that they all contributed to SGD. Third, we further demonstrated a weaker G-dominance on the leading strand of the non-polC group but strong purine dominance (both G and A) on the leading strand of the polC group. We propose that strand-biased nucleotide composition plays a decisive role for SGD since the polC-bearing genomes are not only AT-rich but also have pronounced purine-rich leading strands, and we believe that a special mutation spectrum that leads to a strong purine asymmetry and a strong strand-biased nucleotide composition coupled with functional selections for genes and their functions are both at work. PMID:23084774

  19. Distribution pattern of benthic invertebrates in Danish estuaries

    DEFF Research Database (Denmark)

    Kristensen, Erik; Delefosse, Matthieu; Quintana, Cintia Organo

    2013-01-01

    distribution of 9 dominating benthic invertebrate species from two study areas, the estuaries Odense Fjord and Roskilde Fjord, Denmark. The slope (b) obtained fromthe power relationship of sample variance (s2) versusmean (μ) appears to be species-specific and independent of location and time. It ranges from...... factors such as behavior and intraspecific interactions. Thus, at the examined spatial scale, the more intense intraspecific interactions (e.g. territoriality) cause less aggregated distribution patterns among large- than small-bodied invertebrates. The species-specific interactions seem sufficiently...

  20. Global patterns of city size distributions and their fundamental drivers.

    Directory of Open Access Journals (Sweden)

    Ethan H Decker

    Full Text Available Urban areas and their voracious appetites are increasingly dominating the flows of energy and materials around the globe. Understanding the size distribution and dynamics of urban areas is vital if we are to manage their growth and mitigate their negative impacts on global ecosystems. For over 50 years, city size distributions have been assumed to universally follow a power function, and many theories have been put forth to explain what has become known as Zipf's law (the instance where the exponent of the power function equals unity. Most previous studies, however, only include the largest cities that comprise the tail of the distribution. Here we show that national, regional and continental city size distributions, whether based on census data or inferred from cluster areas of remotely-sensed nighttime lights, are in fact lognormally distributed through the majority of cities and only approach power functions for the largest cities in the distribution tails. To explore generating processes, we use a simple model incorporating only two basic human dynamics, migration and reproduction, that nonetheless generates distributions very similar to those found empirically. Our results suggest that macroscopic patterns of human settlements may be far more constrained by fundamental ecological principles than more fine-scale socioeconomic factors.

  1. Horizontal and Vertical Distributions of Transparent Exopolymer Particles (TEP) in the NW Mediterranean Sea Are Linked to Chlorophyll a and O2 Variability.

    Science.gov (United States)

    Ortega-Retuerta, Eva; Sala, Maria M; Borrull, Encarna; Mestre, Mireia; Aparicio, Fran L; Gallisai, Rachele; Antequera, Carolina; Marrasé, Cèlia; Peters, Francesc; Simó, Rafel; Gasol, Josep M

    2016-01-01

    Transparent Exopolymer Particles (TEP) are relevant in particle and carbon fluxes in the ocean, and have economic impact in the desalination industry affecting reverse osmosis membrane fouling. However, general models of their occurrence and dynamics are not yet possible because of the poorly known co-variations with other physical and biological variables. Here, we describe TEP distributions in the NW Mediterranean Sea during late spring 2012, along perpendicular and parallel transects to the Catalan coast. The stations in the parallel transect were sampled at the surface, while the stations in the perpendicular transect were sampled from the surface to the bathypelagic, including the bottom nepheloid layers. We also followed the short-term TEP dynamics along a 2-day cycle in offshore waters. TEP concentrations in the area ranged from 4.9 to 122.8 and averaged 31.4 ± 12.0 μg XG eq L-1. The distribution of TEP measured in transects parallel to the Catalan Coast correlated those of chlorophyll a (Chla) in May but not in June, when higher TEP-values with respect to Chla were observed. TEP horizontal variability in epipelagic waters from the coast to the open sea also correlated to that of Chla, O2 (that we interpret as a proxy of primary production) and bacterial production (BP). In contrast, the TEP vertical distributions in epipelagic waters were uncoupled from those of Chla, as TEP maxima were located above the deep chlorophyll maxima. The vertical distribution of TEP in the epipelagic zone was correlated with O2 and BP, suggesting combined phytoplankton (through primary production) and bacterial (through carbon reprocessing) TEP sources. However, no clear temporal patterns arose during the 2-day cycle. In meso- and bathypelagic waters, where phytoplanktonic sources are minor, TEP concentrations (10.1 ± 4.3 μg XG eq l-1) were half those in the epipelagic, but we observed relative TEP increments coinciding with the presence of nepheloid layers. These TEP

  2. Human leptospirosis distribution pattern analysis in Hulu Langat, Selangor

    Science.gov (United States)

    Zulkifli, Zuhafiza; Shariff, Abdul Rashid Mohamed; Tarmidi, Zakri M.

    2016-06-01

    This paper discussed the distribution pattern of human leptospirosis in the Hulu Langat District, Selangor, Malaysia. The data used in this study is leptospirosis cases’ report, and spatial boundaries. Leptospirosis cases, data were collected from Health Office of Hulu Langat and spatial boundaries, including lot and district boundaries was collected from the Department of Mapping and Surveying Malaysia (JUPEM). A total of 599 leptospirosis cases were reported in 2013, and this data was mapped based on the addresses provided in the leptospirosis cases’ report. This study uses three statistical methods to analyze the distribution pattern; Moran's I, average nearest neighborhood (ANN) and kernel density estimation. The analysis was used to determine the spatial distribution and the average distance of leptospirosis cases and located the hotspot locations. Using Moran's I analysis, results indicated the cases were random, with a value of -0.202816 which show negative spatial autocorrelation exist among leptospirosis cases. The ANN analysis result, indicated the cases are in cluster pattern, with value of the average nearest neighbor ratio is -21.80. And results also show the hotspots are has been identified and mapped in the Hulu Langat District.

  3. Determinants of the pattern of horizontal and vertical intra-industry trade: what can we learn from Portuguese data?

    OpenAIRE

    Nuno Crespo; Maria Paula Fontoura

    2001-01-01

    We rely on vertical and horizontal differentiation models to study the cross-industry and cross-country determinants of Portuguese intra-industry trade in 1997. We identify distinct factors for each type and the comparative advantage explanation for the vertical case. To confirm the robustness of the results we use alternative measures for a continuous dependent variable and re-estimate all equations with a Probit model. The probabilistic model takes into account the fact that we expect a rel...

  4. Correlating the Horizontal and Vertical Distribution of LiDAR Point Clouds with Components of Biomass in a Picea crassifolia Forest

    OpenAIRE

    Wang Li; Zheng Niu; Shuai Gao; Ni Huang; Hanyue Chen

    2014-01-01

    Light detection and ranging (LiDAR) has been widely used to estimate forest biomass. In this study, we aim to further explore this capability by correlating horizontal and vertical distribution of LiDAR data with components of biomass in a Picea crassifolia forest. Airborne small footprint full-waveform data were decomposed to acquire higher density point clouds. We calculated LiDAR metrics at the tree level and subplot level and correlated them to biomass components, including branch biomass...

  5. Marine biodiversity in the Caribbean: regional estimates and distribution patterns.

    Directory of Open Access Journals (Sweden)

    Patricia Miloslavich

    Full Text Available This paper provides an analysis of the distribution patterns of marine biodiversity and summarizes the major activities of the Census of Marine Life program in the Caribbean region. The coastal Caribbean region is a large marine ecosystem (LME characterized by coral reefs, mangroves, and seagrasses, but including other environments, such as sandy beaches and rocky shores. These tropical ecosystems incorporate a high diversity of associated flora and fauna, and the nations that border the Caribbean collectively encompass a major global marine biodiversity hot spot. We analyze the state of knowledge of marine biodiversity based on the geographic distribution of georeferenced species records and regional taxonomic lists. A total of 12,046 marine species are reported in this paper for the Caribbean region. These include representatives from 31 animal phyla, two plant phyla, one group of Chromista, and three groups of Protoctista. Sampling effort has been greatest in shallow, nearshore waters, where there is relatively good coverage of species records; offshore and deep environments have been less studied. Additionally, we found that the currently accepted classification of marine ecoregions of the Caribbean did not apply for the benthic distributions of five relatively well known taxonomic groups. Coastal species richness tends to concentrate along the Antillean arc (Cuba to the southernmost Antilles and the northern coast of South America (Venezuela-Colombia, while no pattern can be observed in the deep sea with the available data. Several factors make it impossible to determine the extent to which these distribution patterns accurately reflect the true situation for marine biodiversity in general: (1 highly localized concentrations of collecting effort and a lack of collecting in many areas and ecosystems, (2 high variability among collecting methods, (3 limited taxonomic expertise for many groups, and (4 differing levels of activity in the study

  6. Marine Biodiversity in the Caribbean: Regional Estimates and Distribution Patterns

    Science.gov (United States)

    Miloslavich, Patricia; Díaz, Juan Manuel; Klein, Eduardo; Alvarado, Juan José; Díaz, Cristina; Gobin, Judith; Escobar-Briones, Elva; Cruz-Motta, Juan José; Weil, Ernesto; Cortés, Jorge; Bastidas, Ana Carolina; Robertson, Ross; Zapata, Fernando; Martín, Alberto; Castillo, Julio; Kazandjian, Aniuska; Ortiz, Manuel

    2010-01-01

    This paper provides an analysis of the distribution patterns of marine biodiversity and summarizes the major activities of the Census of Marine Life program in the Caribbean region. The coastal Caribbean region is a large marine ecosystem (LME) characterized by coral reefs, mangroves, and seagrasses, but including other environments, such as sandy beaches and rocky shores. These tropical ecosystems incorporate a high diversity of associated flora and fauna, and the nations that border the Caribbean collectively encompass a major global marine biodiversity hot spot. We analyze the state of knowledge of marine biodiversity based on the geographic distribution of georeferenced species records and regional taxonomic lists. A total of 12,046 marine species are reported in this paper for the Caribbean region. These include representatives from 31 animal phyla, two plant phyla, one group of Chromista, and three groups of Protoctista. Sampling effort has been greatest in shallow, nearshore waters, where there is relatively good coverage of species records; offshore and deep environments have been less studied. Additionally, we found that the currently accepted classification of marine ecoregions of the Caribbean did not apply for the benthic distributions of five relatively well known taxonomic groups. Coastal species richness tends to concentrate along the Antillean arc (Cuba to the southernmost Antilles) and the northern coast of South America (Venezuela – Colombia), while no pattern can be observed in the deep sea with the available data. Several factors make it impossible to determine the extent to which these distribution patterns accurately reflect the true situation for marine biodiversity in general: (1) highly localized concentrations of collecting effort and a lack of collecting in many areas and ecosystems, (2) high variability among collecting methods, (3) limited taxonomic expertise for many groups, and (4) differing levels of activity in the study of

  7. Marine biodiversity in the Caribbean: regional estimates and distribution patterns.

    Science.gov (United States)

    Miloslavich, Patricia; Díaz, Juan Manuel; Klein, Eduardo; Alvarado, Juan José; Díaz, Cristina; Gobin, Judith; Escobar-Briones, Elva; Cruz-Motta, Juan José; Weil, Ernesto; Cortés, Jorge; Bastidas, Ana Carolina; Robertson, Ross; Zapata, Fernando; Martín, Alberto; Castillo, Julio; Kazandjian, Aniuska; Ortiz, Manuel

    2010-08-02

    This paper provides an analysis of the distribution patterns of marine biodiversity and summarizes the major activities of the Census of Marine Life program in the Caribbean region. The coastal Caribbean region is a large marine ecosystem (LME) characterized by coral reefs, mangroves, and seagrasses, but including other environments, such as sandy beaches and rocky shores. These tropical ecosystems incorporate a high diversity of associated flora and fauna, and the nations that border the Caribbean collectively encompass a major global marine biodiversity hot spot. We analyze the state of knowledge of marine biodiversity based on the geographic distribution of georeferenced species records and regional taxonomic lists. A total of 12,046 marine species are reported in this paper for the Caribbean region. These include representatives from 31 animal phyla, two plant phyla, one group of Chromista, and three groups of Protoctista. Sampling effort has been greatest in shallow, nearshore waters, where there is relatively good coverage of species records; offshore and deep environments have been less studied. Additionally, we found that the currently accepted classification of marine ecoregions of the Caribbean did not apply for the benthic distributions of five relatively well known taxonomic groups. Coastal species richness tends to concentrate along the Antillean arc (Cuba to the southernmost Antilles) and the northern coast of South America (Venezuela-Colombia), while no pattern can be observed in the deep sea with the available data. Several factors make it impossible to determine the extent to which these distribution patterns accurately reflect the true situation for marine biodiversity in general: (1) highly localized concentrations of collecting effort and a lack of collecting in many areas and ecosystems, (2) high variability among collecting methods, (3) limited taxonomic expertise for many groups, and (4) differing levels of activity in the study of different

  8. Towards Scalable Distributed Framework for Urban Congestion Traffic Patterns Warehousing

    Directory of Open Access Journals (Sweden)

    A. Boulmakoul

    2015-01-01

    Full Text Available We put forward architecture of a framework for integration of data from moving objects related to urban transportation network. Most of this research refers to the GPS outdoor geolocation technology and uses distributed cloud infrastructure with big data NoSQL database. A network of intelligent mobile sensors, distributed on urban network, produces congestion traffic patterns. Congestion predictions are based on extended simulation model. This model provides traffic indicators calculations, which fuse with the GPS data for allowing estimation of traffic states across the whole network. The discovery process of congestion patterns uses semantic trajectories metamodel given in our previous works. The challenge of the proposed solution is to store patterns of traffic, which aims to ensure the surveillance and intelligent real-time control network to reduce congestion and avoid its consequences. The fusion of real-time data from GPS-enabled smartphones integrated with those provided by existing traffic systems improves traffic congestion knowledge, as well as generating new information for a soft operational control and providing intelligent added value for transportation systems deployment.

  9. Stress distribution in maxillary first molar periodontium using straight pull headgear with vertical and horizontal tubes: A finite element analysis

    Directory of Open Access Journals (Sweden)

    Masood Feizbakhsh

    2017-01-01

    Conclusion: Based on the results, when force applied to the straight pull headgear with a vertical tube, Von Mises stress was reduced significantly in comparison with the horizontal tube. Therefore, to correct the mesiolingual movement of the maxillary first molar, vertical headgear tube is recommended.

  10. Correlating the Horizontal and Vertical Distribution of LiDAR Point Clouds with Components of Biomass in a Picea crassifolia Forest

    Directory of Open Access Journals (Sweden)

    Wang Li

    2014-08-01

    Full Text Available Light detection and ranging (LiDAR has been widely used to estimate forest biomass. In this study, we aim to further explore this capability by correlating horizontal and vertical distribution of LiDAR data with components of biomass in a Picea crassifolia forest. Airborne small footprint full-waveform data were decomposed to acquire higher density point clouds. We calculated LiDAR metrics at the tree level and subplot level and correlated them to biomass components, including branch biomass (BB, leaf biomass (LB and above-ground biomass (AGB, respectively. A new metric (Horizcv describing the horizontal distribution of point clouds was proposed. This metric was found to be highly correlated with canopy biomass (BB and LB at the tree level and subplot level. Correlation between AGB and Horizcv at the subplot level is much lower than that at tree level. AGB for subplot is highly correlated with the mean height metric (Hmean, canopy cover index (CCI and the product of them. On the other hand, the relationship between the vertical distribution of LiDAR point and biomass was explored by developing two types of vertical profiles, including LiDAR distribution profiles and a biomass profile. Good relationships were found between these two types of vertical profiles and assessed by Pearson’s correlation coefficient (R and the area of overlap index (AOI. These good correlations possess potential in predicting the vertical distribution of canopy biomass. Overall, it is concluded that not only the vertical, but also the horizontal distribution of LiDAR points should be taken into account in estimating components of biomass by LiDAR.

  11. Storm blueprints patterns for distributed real-time computation

    CERN Document Server

    Goetz, P Taylor

    2014-01-01

    A blueprints book with 10 different projects built in 10 different chapters which demonstrate the various use cases of storm for both beginner and intermediate users, grounded in real-world example applications.Although the book focuses primarily on Java development with Storm, the patterns are more broadly applicable and the tips, techniques, and approaches described in the book apply to architects, developers, and operations.Additionally, the book should provoke and inspire applications of distributed computing to other industries and domains. Hadoop enthusiasts will also find this book a go

  12. Probability Measure of Navigation pattern predition using Poisson Distribution Analysis

    OpenAIRE

    Dr.V.Valli Mayil; Ms. R. Rooba; Ms. C. Parimala

    2012-01-01

    The World Wide Web has become one of the most important media to store, share and distribute information. The rapid expansion of the web has provided a great opportunity to study user and system behavior by exploring web access logs. Web Usage Mining is the application of data mining techniques to large web data repositories in order to extract usage patterns. Every web server keeps a log of all transactions between the server and the clients. The log data which are collected by web servers c...

  13. Horizontal Accelerator

    Data.gov (United States)

    Federal Laboratory Consortium — The Horizontal Accelerator (HA) Facility is a versatile research tool available for use on projects requiring simulation of the crash environment. The HA Facility is...

  14. Daily pattern of energy distribution and weight loss.

    Science.gov (United States)

    Raynor, Hollie A; Li, Fan; Cardoso, Chelsi

    2018-02-19

    Timing of energy intake, a temporal dietary pattern, may enhance health. Eating a greater amount of energy earlier and a smaller amount of energy later in the day, a behavioral circadian rhythm, may assist with chronoenhancement. Chronoenhancement seeks to enhance entrainment (synchronization) of biological and behavioral circadian rhythms. In humans, research reports that eating a greater amount of energy early and a smaller amount of energy later in the day increases dietary induced thermogenesis, improves cardiometabolic outcomes, and enhances weight loss. However, little human research has examined if this eating pattern enhances regularity of biological circadian rhythm. In a randomized controlled 8-week pilot study, the influence of energy distribution timing on weight loss and regularity of sleep onset and wake times (marker for biological circadian rhythm) was examined. Within an hypocaloric, three-meal prescription, participants (n = 8) were assigned to either: 1) Morning: 50%, 30%, and 20% of kcal at breakfast, lunch, and dinner, respectively; or 2) Evening: 20%, 30%, and 50% of kcal at breakfast, lunch, and dinner, respectively. Percent weight loss and regularity of sleep onset and wake times were significantly (p energy distribution timing on health, longer studies conducted in free-living participants, with dietary intake assessed using time-stamped methods, that include measures of the circadian timing system are needed. This small review is based upon a symposium presentation at the Society of the Study of Ingestive Behavior in 2017. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Enhancement of force patterns classification based on Gaussian distributions.

    Science.gov (United States)

    Ertelt, Thomas; Solomonovs, Ilja; Gronwald, Thomas

    2018-01-23

    Description of the patterns of ground reaction force is a standard method in areas such as medicine, biomechanics and robotics. The fundamental parameter is the time course of the force, which is classified visually in particular in the field of clinical diagnostics. Here, the knowledge and experience of the diagnostician is relevant for its assessment. For an objective and valid discrimination of the ground reaction force pattern, a generic method, especially in the medical field, is absolutely necessary to describe the qualities of the time-course. The aim of the presented method was to combine the approaches of two existing procedures from the fields of machine learning and the Gauss approximation in order to take advantages of both methods for the classification of ground reaction force patterns. The current limitations of both methods could be eliminated by an overarching method. Twenty-nine male athletes from different sports were examined. Each participant was given the task of performing a one-legged stopping maneuver on a force plate from the maximum possible starting speed. The individual time course of the ground reaction force of each subject was registered and approximated on the basis of eight Gaussian distributions. The descriptive coefficients were then classified using Bayesian regulated neural networks. The different sports served as the distinguishing feature. Although the athletes were all given the same task, all sports referred to a different quality in the time course of ground reaction force. Meanwhile within each sport, the athletes were homogeneous. With an overall prediction (R = 0.938) all subjects/sports were classified correctly with 94.29% accuracy. The combination of the two methods: the mathematical description of the time course of ground reaction forces on the basis of Gaussian distributions and their classification by means of Bayesian regulated neural networks, seems an adequate and promising method to discriminate the

  16. Horizontal movements, migration patterns, and population structure of whale sharks in the Gulf of Mexico and northwestern Caribbean sea.

    Science.gov (United States)

    Hueter, Robert E; Tyminski, John P; de la Parra, Rafael

    2013-01-01

    Whale sharks, Rhincodon typus, aggregate by the hundreds in a summer feeding area off the northeastern Yucatan Peninsula, Mexico, where the Gulf of Mexico meets the Caribbean Sea. The aggregation remains in the nutrient-rich waters off Isla Holbox, Isla Contoy and Isla Mujeres, Quintana Roo for several months in the summer and then dissipates between August and October. Little has been known about where these sharks come from or migrate to after they disperse. From 2003-2012, we used conventional visual tags, photo-identification, and satellite tags to characterize the basic population structure and large-scale horizontal movements of whale sharks that come to this feeding area off Mexico. The aggregation comprised sharks ranging 2.5-10.0 m in total length and included juveniles, subadults, and adults of both sexes, with a male-biased sex ratio (72%). Individual sharks remained in the area for an estimated mean duration of 24-33 days with maximum residency up to about 6 months as determined by photo-identification. After leaving the feeding area the sharks showed horizontal movements in multiple directions throughout the Gulf of Mexico basin, the northwestern Caribbean Sea, and the Straits of Florida. Returns of individual sharks to the Quintana Roo feeding area in subsequent years were common, with some animals returning for six consecutive years. One female shark with an estimated total length of 7.5 m moved at least 7,213 km in 150 days, traveling through the northern Caribbean Sea and across the equator to the South Atlantic Ocean where her satellite tag popped up near the Mid-Atlantic Ridge. We hypothesize this journey to the open waters of the Mid-Atlantic was for reproductive purposes but alternative explanations are considered. The broad movements of whale sharks across multiple political boundaries corroborates genetics data supporting gene flow between geographically distinct areas and underscores the need for management and conservation strategies for

  17. Do infants have the horizontal bias?

    Science.gov (United States)

    Van Renswoude, D R; Johnson, S P; Raijmakers, M E J; Visser, I

    2016-08-01

    A robust set of studies show that adults make more horizontal than vertical and oblique saccades, while scanning real-world scenes. In this paper we study the horizontal bias in infants. The directions of eye movements were calculated for 41 infants (M=8.40 months, SD=3.74, range=3.48-15.47) and 47 adults (M=21.74 years, SD=4.54, range=17.89-39.84) while viewing 28 real-world scenes. Saccade directions were binned to study the proportion of saccades in the horizontal, vertical and oblique directions. In addition, saccade directions were also modeled using a mixture of Von Mises distributions, to account for the relatively large amount of variance in infants data. Horizontal bias was replicated in adults and also found in infants, using both the binning and Von Mises approach. Moreover, a developmental pattern was observed in which older infants are more precise in targeting their saccades than younger infants. That infants have a horizontal bias is important in understanding infants' eye movements. Future studies should account for the horizontal bias in their designs and analyses. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. The population distribution pattern in Xinjiang autonomous region.

    Science.gov (United States)

    Yuan, X

    1994-01-01

    Population distribution in Xinjiang Autonomous Region in China follows a high-density horseshoe-shaped pattern of oases surrounded by mountains and desert comprising 70% of the territory. The Region has the largest geographic area of all provinces, has 15.8 million people, and a population density of 9.5/sq. km. 90% of the total population lives in the more than 500 oases, with a population density of 200 people/sq. km. About 80% of the population has lived in the northwestern part of the province over the past 40 years; density is 15.5 people/sq. km compared to only 3.2 people/sq. km in the southeast. Population concentration is affected by natural resource distribution (water), industrial and agricultural production, transportation, and immigration. Population density increased by 4.7 times in northern Xinjiang, 1.2 times in the south, and 2.9 times in the east. Population concentration is also affected by elevation patterns. The largest population (46.33%) is situated in areas 1000-1500 meters above sea level, with declines at either increased or decreased elevations. Population density declines as elevation increases. Most of the old oases were situated in basins between 500 and 1000 meters in the north and between 1000 and 1500 meters in the south. Areas below 500 meters in the north and areas below 100 meters in the south are desert. Population distribution varied among the southern slope of the Altay Mountains, the northern slope of the Tianshan Mountains between 100 and 2500 meters, the eastern part of the northern slope of the Tianshan Mountains, the southern slope of the Tianshan Mountains, the western part of the southern slope of the Tianshan Mountains, the northern slope of the Kunlun Mountains, in Pamirs and the eastern slope of the Tianshan Mountains, and old oases at 500-1000 meters in the heart of Xinjiang, where major transportation routes cross China.

  19. Agricultural Terrace Pattern Distribution and Preservation along Climatic Gradient

    Science.gov (United States)

    Ackermann, Oren

    2017-04-01

    Agricultural terraces are a well-distributed agrotechnical method for planting in various places in the world, from ancient time and until today. The aim of the current research is to demonstrate the spatial distribution and conservation of agricultural terraces along a climatic gradient of sub-humid Mediterranean, semi-arid and arid climate zones by presenting the case study of the Land of Israel. In the Judean Mountains (central Israel), a region under sub-humid Mediterranean conditions, agricultural terraces are characterized by terrace coverage on slopes and in valleys. Annual rainfall average in this region is 800 mm, allowing for vast rain-fed agriculture based on direct rain. In the Judean Shephelah (central Israel), a region under semi-arid conditions, agriculture terraces are located in small spots on the slopes, and in terrace fields in the valleys. Annual average rainfall in this region is between 300 and 400 mm. Rain-fed agriculture was sustained by direct rain and additional runoff generated on rock outcrops. In the Negev Highlands, (southern Israel), a region under arid climate conditions with annual rainfall average of 100 mm, runoff farm terraces are located in valleys, and agriculture sustenance was based on water harvesting from the slopes. The terraces pattern distribution is similar to the natural vegetation pattern distribution of the three given areas. During the past ten of years, changes in land use and farming methods have resulted in the abandonment of many agricultural terraces in the given areas. Terrace abandonment leads to the collapse of retaining walls and erosion of soil and sediments from the terrace body with the latter occurring at a high rate in the arid Negev highlands. However, in the Judean Mountains and the Judean Shephelah, areas under sub-humid Mediterranean and semi-arid conditions, the intensity of erosion is lower since the terraces are covered by dense shrubs such as Sarcopoterium spinosum or by trees. This plant cover

  20. Modelling spatiotemporal distribution patterns of earthworms in order to indicate hydrological soil processes

    Science.gov (United States)

    Palm, Juliane; Klaus, Julian; van Schaik, Loes; Zehe, Erwin; Schröder, Boris

    2010-05-01

    Soils provide central ecosystem functions in recycling nutrients, detoxifying harmful chemicals as well as regulating microclimate and local hydrological processes. The internal regulation of these functions and therefore the development of healthy and fertile soils mainly depend on the functional diversity of plants and animals. Soil organisms drive essential processes such as litter decomposition, nutrient cycling, water dynamics, and soil structure formation. Disturbances by different soil management practices (e.g., soil tillage, fertilization, pesticide application) affect the distribution and abundance of soil organisms and hence influence regulating processes. The strong relationship between environmental conditions and soil organisms gives us the opportunity to link spatiotemporal distribution patterns of indicator species with the potential provision of essential soil processes on different scales. Earthworms are key organisms for soil function and affect, among other things, water dynamics and solute transport in soils. Through their burrowing activity, earthworms increase the number of macropores by building semi-permanent burrow systems. In the unsaturated zone, earthworm burrows act as preferential flow pathways and affect water infiltration, surface-, subsurface- and matrix flow as well as the transport of water and solutes into deeper soil layers. Thereby different ecological earthworm types have different importance. Deep burrowing anecic earthworm species (e.g., Lumbricus terrestris) affect the vertical flow and thus increase the risk of potential contamination of ground water with agrochemicals. In contrast, horizontal burrowing endogeic (e.g., Aporrectodea caliginosa) and epigeic species (e.g., Lumbricus rubellus) increase water conductivity and the diffuse distribution of water and solutes in the upper soil layers. The question which processes are more relevant is pivotal for soil management and risk assessment. Thus, finding relevant

  1. GEMAS: Molybdenum Spatial Distribution Patterns in European Soil

    Science.gov (United States)

    Cicchella, Domenico; Zuzolo, Daniela; Demetriades, Alecos; De Vivo, Benedetto; Eklund, Mikael; Ladenberger, Anna; Negrel, Philippe; O'Connor, Patrick

    2017-04-01

    Molybdenum is an essential trace element for both plants and animals as well as for human being. It is one such trace element for which potential health concerns have been raised but for which few data exist and little investigation or interpretation of distributions in soils has been made. The main goal of this study was to fill this gap. Molybdenum (Mo) concentrations are reported for the interesting anomalous patterns occur also in Italy in correspondence with alkaline volcanics, in Spain and Greece associated with sulfides mineralizations and in Slovenia and Croatia where are probably related to the long weathering history of karstic residual soils. Anomalous concentrations in some areas of Ireland represent a clear example of how an excess of molybdenum has produced potentially toxic pastures. In fact, these give rise to problems particularly in young cattle when excess molybdenum in the herbage acts as an antagonist, which militates against efficient copper absorption by the animal.

  2. Do stacked species distribution models reflect altitudinal diversity patterns?

    Directory of Open Access Journals (Sweden)

    Rubén G Mateo

    Full Text Available The objective of this study was to evaluate the performance of stacked species distribution models in predicting the alpha and gamma species diversity patterns of two important plant clades along elevation in the Andes. We modelled the distribution of the species in the Anthurium genus (53 species and the Bromeliaceae family (89 species using six modelling techniques. We combined all of the predictions for the same species in ensemble models based on two different criteria: the average of the rescaled predictions by all techniques and the average of the best techniques. The rescaled predictions were then reclassified into binary predictions (presence/absence. By stacking either the original predictions or binary predictions for both ensemble procedures, we obtained four different species richness models per taxa. The gamma and alpha diversity per elevation band (500 m was also computed. To evaluate the prediction abilities for the four predictions of species richness and gamma diversity, the models were compared with the real data along an elevation gradient that was independently compiled by specialists. Finally, we also tested whether our richness models performed better than a null model of altitudinal changes of diversity based on the literature. Stacking of the ensemble prediction of the individual species models generated richness models that proved to be well correlated with the observed alpha diversity richness patterns along elevation and with the gamma diversity derived from the literature. Overall, these models tend to overpredict species richness. The use of the ensemble predictions from the species models built with different techniques seems very promising for modelling of species assemblages. Stacking of the binary models reduced the over-prediction, although more research is needed. The randomisation test proved to be a promising method for testing the performance of the stacked models, but other implementations may still be

  3. Do stacked species distribution models reflect altitudinal diversity patterns?

    Science.gov (United States)

    Mateo, Rubén G; Felicísimo, Ángel M; Pottier, Julien; Guisan, Antoine; Muñoz, Jesús

    2012-01-01

    The objective of this study was to evaluate the performance of stacked species distribution models in predicting the alpha and gamma species diversity patterns of two important plant clades along elevation in the Andes. We modelled the distribution of the species in the Anthurium genus (53 species) and the Bromeliaceae family (89 species) using six modelling techniques. We combined all of the predictions for the same species in ensemble models based on two different criteria: the average of the rescaled predictions by all techniques and the average of the best techniques. The rescaled predictions were then reclassified into binary predictions (presence/absence). By stacking either the original predictions or binary predictions for both ensemble procedures, we obtained four different species richness models per taxa. The gamma and alpha diversity per elevation band (500 m) was also computed. To evaluate the prediction abilities for the four predictions of species richness and gamma diversity, the models were compared with the real data along an elevation gradient that was independently compiled by specialists. Finally, we also tested whether our richness models performed better than a null model of altitudinal changes of diversity based on the literature. Stacking of the ensemble prediction of the individual species models generated richness models that proved to be well correlated with the observed alpha diversity richness patterns along elevation and with the gamma diversity derived from the literature. Overall, these models tend to overpredict species richness. The use of the ensemble predictions from the species models built with different techniques seems very promising for modelling of species assemblages. Stacking of the binary models reduced the over-prediction, although more research is needed. The randomisation test proved to be a promising method for testing the performance of the stacked models, but other implementations may still be developed.

  4. Vertical and horizontal distribution of sediment nitrite-dependent methane-oxidizing organisms in a mesotrophic freshwater reservoir.

    Science.gov (United States)

    Long, Yan; Liu, Changbao; Lin, Hengliang; Li, Ningning; Guo, Qingwei; Xie, Shuguang

    2017-06-01

    In the present study, we investigated the spatial change of sediment nitrite-dependent anaerobic methane-oxidizing (n-damo) organisms in the mesotrophic freshwater Gaozhou Reservoir (6 different sampling locations and 2 sediment depths (0-5 cm, 5-10 cm)), one of the largest drinking water reservoirs in China. The abundance of sediment n-damo bacteria was quantified using quantitative polymerase chain reaction assay, while the richness, diversity, and composition of n-damo pmoA gene sequences were characterized using clone library analysis. Vertical and horizontal changes in sediment n-damo bacterial abundance occurred in Gaozhou Reservoir, with 1.37 × 105 to 8.24 × 105 n-damo 16S rRNA gene copies per gram of dry sediment. Considerable horizontal and vertical variations of n-damo pmoA gene diversity (Shannon index = 0.32-2.50) and composition also occurred in this reservoir. Various types of sediment n-damo pmoA genes existed in Gaozhou Reservoir. A small proportion of n-damo pmoA gene sequences (19.1%) were related to those recovered from "Candidatus Methylomirabilis oxyfera". Our results suggested that sediment n-damo pmoA gene diversity might be regulated by nitrite, while n-damo pmoA gene richness might be governed by multiple environmental factors, including total organic carbon, total phosphorus, nitrite, and total nitrogen.

  5. EARTHQUAKE RESPONSE ANALYSIS OF A VIADUCT WITH HORIZONTAL FORCE DISTRIBUTED STRUCTURE USING STRONG MOTION OBSERVED DURING THE 2011 OFF THE PACIFIC COAST OF TOHOKU EARTHQUAKE

    Science.gov (United States)

    Kataoka, Shojiro; Nagaya, Kazuhiro; Yabe, Masaaki; Matsuoka, Kazunari; Kaneko, Masahiro

    Dynamic analysis is widely used for the seismic design of the bridge with horizontal force distributed structure in recent years. There is few research on dynamic analysis of such bridges using real earthquake data. In this research, we carried out dynamic analysis using accelerograms recorded during the 2011 off the Pacific coast of Tohoku earthquake (Mw9.0). The analytical earthquake response shows a good agreement with the observed response when colliding and friction forces acted between sideblocks and shoes are taken into account.

  6. Visualization of oxygen distribution patterns caused by coral and algae

    Directory of Open Access Journals (Sweden)

    Andreas F. Haas

    2013-07-01

    Full Text Available Planar optodes were used to visualize oxygen distribution patterns associated with a coral reef associated green algae (Chaetomorpha sp. and a hermatypic coral (Favia sp. separately, as standalone organisms, and placed in close proximity mimicking coral-algal interactions. Oxygen patterns were assessed in light and dark conditions and under varying flow regimes. The images show discrete high oxygen concentration regions above the organisms during lighted periods and low oxygen in the dark. Size and orientation of these areas were dependent on flow regime. For corals and algae in close proximity the 2D optodes show areas of extremely low oxygen concentration at the interaction interfaces under both dark (18.4 ± 7.7 µmol O2 L- 1 and daylight (97.9 ± 27.5 µmol O2 L- 1 conditions. These images present the first two-dimensional visualization of oxygen gradients generated by benthic reef algae and corals under varying flow conditions and provide a 2D depiction of previously observed hypoxic zones at coral algae interfaces. This approach allows for visualization of locally confined, distinctive alterations of oxygen concentrations facilitated by benthic organisms and provides compelling evidence for hypoxic conditions at coral-algae interaction zones.

  7. Distributional patterns of cecropia (Cecropiaceae: a panbiogeographic analysis

    Directory of Open Access Journals (Sweden)

    Franco Rosselli Pilar

    1997-06-01

    Full Text Available A panbiogeographic analysis of the distributional patterns of 60 species of Cecropia was carried out. Based on the distributional ranges of 36 species, we found eight generalized tracks for Cecropia species. whereas distributional patterns of 24 species were uninformative for the analysis. The major concentration of species of Cecropia is in the Neotropical Andean region. where there are three generalized tracks and two nodes. The northern Andes in Colombia and Ecuador are richer than the Central Andes in Perú. they contain two generalized tracks; one to the west and another to the east, formed by individual tracks of eight species each. There are four generalized tracks outside the Andean region: two in the Amazonian region in Guayana-Pará and in Manaus. one in Roraima. one in Serra do Mar in the Atlantic forest of Brazil and one in Central America. Speciation in Cecropia may be related to the Andean first uplift.Con base en la distribución de 60 especies del género Cecropia, se hizo un análisis panbiogeográfico. Se construyeron 8 trazos generalizados con base en el patrón de distribución de 36 especies; la distribución de las demás especies no aportaba información para la definición de los trazos. La región andina tiene la mayor concentración de especies de Cecropia representada por la presencia de tres trazos generalizados y dos nodos; los dos trazos con mayor número de especies se localizan en su parte norte, en Colombia y Ecuador y el otro en los Andes centrales en Perú. Se encontraron además, cuatro trazos extrandinos: dos en la región amazónica, en Pará-Guayana y en Manaus, uno en Roraima, uno en Serra do Mar en la Selva Atlánfíca del Brasil y uno en Centro América. La especiación en Cecropia parece estar relacionada con el primer levantamiento de los Andes.

  8. The structure and spatio-temporal distribution of the Archaea in a horizontal subsurface flow constructed wetland.

    Science.gov (United States)

    Bouali, Moez; Zrafi-Nouira, Ines; Bakhrouf, Amina; Le Paslier, Denis; Chaussonnerie, Sébastien; Ammar, Emna; Sghir, Abdelghani

    2012-10-01

    In this study, archaeal community structure and temporal dynamics were monitored, using 16S rRNA clone libraries construction from a horizontal subsurface flow constructed wetland. Phylogenetic assignation of 1026 16S rRNA gene sequences shows that 96.2% of the total operational taxonomic units (OTUs) were affiliated with Thaumarchaeota, a newly proposed archaeal phylum and 3.7% with unclassified Archaea. Among the total sequences, 42% and 40.2% were affiliated with Candidatus Nitrososphaera and unclassified Nitrosopumilus respectively with more than 99% similarity. Results suggest that several dominant and active nitrifiers may benefit from the micro-aerobic conditions around the reed roots to perform ammonia oxidation. The archaeal diversity detected in the rhizosphere zone is clearly different from that detected in the bottom basin. This engineered habitat revealed the reed root and the water composition effects on the archaeal diversity. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. The effect of horizontal gradients and spatial measurement resolution on the retrieval of global vertical NO2 distributions from SCIAMACHY measurements in limb only mode

    Directory of Open Access Journals (Sweden)

    U. Platt

    2010-08-01

    Full Text Available Limb measurements provided by the Scanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY on the ENVISAT satellite allow retrieving stratospheric profiles of various trace gases on a global scale. Combining measurements of the same air volume from different viewing positions along the orbit, a tomographic approach can be applied and 2-D distribution fields of stratospheric trace gases can be acquired in one inversion. With this approach, it is possible to improve the accounting for the effect of horizontal gradients in the trace gas distribution on the profile retrieval. This was shown in a previous study for the retrieval of NO2 and OClO profiles in the Arctic region near the polar vortex boundary. In this study, the tomographic retrieval is applied on measurements during special limb-only orbits performed on 14 December 2008. For these orbits the distance between consecutive limb scanning sequences was reduced to ~3.3° of the orbital circle (i.e. more than two times with respect to the nominal operational mode. Thus, the same air volumes are scanned successively by more than one scanning sequence also for midlatitudes and the tropics. It is found that the profiles obtained by the tomographic 2-D approach show significant differences to those obtained by the 1-D approach. In particular, for regions close to stratospheric transport barriers (i.e. near to the edge of the polar vortex and subtropical transport barrier up to 50% larger or smaller NO2 number densities (depending on the sign of the gradient along the line of sight for altitudes below the peak of the profile (around 20 km are obtained. The limb-only measurements allow examining the systematic error if the horizontal gradient is not accounted for, and studying the impact of the gradient strength on the profile retrieval on a global scale. The findings for the actual SCIAMACHY observations are verified by sensitivity studies for simulated data for which the NO2

  10. Multi-beam raindrop size distributions retrievals on the Doppler spectra : Influence of averaging and mean horizontal wind correction

    NARCIS (Netherlands)

    Unal, C.M.H.

    2012-01-01

    Acquiring the raindrop size distribution (DSD) from radar data is still a challenge. For profiling radar, this distribution can be estimated from the Doppler spectra. However the Doppler spectrum is not a direct measure of the DSD. The radial component of the wind shifts the Doppler spectrum related

  11. Distribution patterns, stock size and life-history strategies of cape ...

    African Journals Online (AJOL)

    Research surveys of Cape horse mackerel Trachurus trachurus capensis abundance on the south coast of South Africa are complicated because changes in the species' vertical and horizontal distribution limit the value of stock assessments based a single survey method. Annual bottom trawl surveys conducted in spring ...

  12. Effect of Vegetation Patterns on SAR derived Surface Soil Moisture Distribution

    Science.gov (United States)

    Koyama, C. N.; Schneider, K.

    2012-12-01

    Soil moisture can be regarded as one of the important life sustaining entities on our planet. Among its various functions, the first is probably to enable the growth of vegetation on the land surface. Apart from this, water stored in soils plays many other important roles in the global water (and energy) cycle. In the past decades, radar imaging has proven its potential to quantitatively estimate the near surface water content of soils at high spatial resolutions. The use of active microwave data to measure surface soil moisture requires the consideration of several factors like e.g. soil texture, surface roughness, and vegetation. Among these factors, the presence of a vegetation cover is perhaps the major impediment to accurate quantitative retrievals of soil moisture. On the one hand, the vegetation has a disturbing effect on the radar reflectivity and thus causes errors in the soil moisture retrieval which is generally based on theoretical or experimental relationships between the dielectric properties of the soil surface and the radar backscattering coefficient. On the other hand, the spatial distribution of vegetation with e.g. different crop types with different transpiration coefficients and different phenological development, etc, can cause large variations in the plant water consumption and thus has a significant impact on the soil moisture patterns. We have developed methods to estimate the amount of biomass for different crop types and the underlying surface soil water content directly from polarimetric L-band SAR images. While the horizontally-transmit horizontally-receive co-polarization (hh) is most sensitive towards the dielectric soil properties, the horizontally-transmit vertically-receive cross-polarization (hv) is much more sensitive towards the backscattering from the vegetation canopy. In addition the polarimetric observables entropy (H), alpha angle (α), and the total reflected power (span), all of which are highly affected by the canopy

  13. Satellite Image Edge Detection for Population Distribution Pattern Identification using Levelset with Morphological Filtering Process

    Science.gov (United States)

    Harsiti; Munandar, T. A.; Suhendar, A.; Abdullah, A. G.; Rohendi, D.

    2017-03-01

    Population distribution pattern is directly related with economic gap of a region. Analysis of population distribution pattern is usually performed by studying statistical data on population. This study aimed to analyze population distribution pattern using image analysis concept, i.e. using satellite images. Levelset and morphological image filtering methods were used to analyze images to see distribution pattern. The research result showed that Levelset and morphological image filtering could remove a lot of noises in analysis result images and form object edge contours very clearly. The detected object contours were used as references to recognize population distribution pattern based on satellite image analysis. The pattern made based on the research result didn’t show optimal result because Levelset performed image segmentation based on the contours of the analyzed objects. Other segmentation methods should be combined with it to produce clearer population distribution pattern.

  14. Within-twig leaf distribution patterns differ among plant life-forms in a subtropical Chinese forest.

    Science.gov (United States)

    Meng, Fengqun; Cao, Rui; Yang, Dongmei; Niklas, Karl J; Sun, Shucun

    2013-07-01

    In theory, plants can alter the distribution of leaves along the lengths of their twigs (i.e., within-twig leaf distribution patterns) to optimize light interception in the context of the architectures of their leaves, branches and canopies. We hypothesized that (i) among canopy tree species sharing similar light environments, deciduous trees will have more evenly spaced within-twig leaf distribution patterns compared with evergreen trees (because deciduous species tend to higher metabolic demands than evergreen species and hence require more light), and that (ii) shade-adapted evergreen species will have more evenly spaced patterns compared with sun-adapted evergreen ones (because shade-adapted species are generally light-limited). We tested these hypotheses by measuring morphological traits (i.e., internode length, leaf area, lamina mass per area, LMA; and leaf and twig inclination angles to the horizontal) and physiological traits (i.e., light-saturated net photosynthetic rates, Amax; light saturation points, LSP; and light compensation points, LCP), and calculated the 'evenness' of within-twig leaf distribution patterns as the coefficient of variation (CV; the higher the CV, the less evenly spaced leaves) of within-twig internode length for 9 deciduous canopy tree species, 15 evergreen canopy tree species, 8 shade-adapted evergreen shrub species and 12 sun-adapted evergreen shrub species in a subtropical broad-leaved rainforest in eastern China. Coefficient of variation was positively correlated with large LMA and large leaf and twig inclination angles, which collectively specify a typical trait combination adaptive to low light interception, as indicated by both ordinary regression and phylogenetic generalized least squares analyses. These relationships were also valid within the evergreen tree species group (which had the largest sample size). Consistent with our hypothesis, in the canopy layer, deciduous species (which were characterized by high LCP, LSP and

  15. Distribution pattern of cholinesterase enzymes in human tooth germs.

    Science.gov (United States)

    Nandasena, T L; Jayawardena, C K; Tilakaratne, W M; Nanayakkara, C D

    2010-08-01

    The two distinct molecular forms of cholinesterase (ChE) are acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Our previous studies have reported that ChE is involved in tooth development. However, further experiments are needed to understand the precise action of ChE in tooth development. This study aimed to localise types of ChE in human tooth germs, and identify their distribution pattern. ChE were localised in frozen sections of jaws which were prepared from dead fetuses, neonates and stillborns who were free from visible abnormalities by Karnovsky and Root method. AChE was identified in the inner and outer enamel epithelia including the cervical loop region, stratum intermedium and preameloblasts of tooth germs at bell stage. Secretory ameloblasts were free from staining. The bud and cap stages of permanent tooth germs showed AChE activity on the lingual aspect and top surface of the epithelial ingrowths, respectively. BuChE activity was localised in the degenerating dental lamina. Our study reported the first evidence of localisation of ChE in human tooth development and identified the possible molecular form of ChE in tooth germs as AChE. Also, our results have provided strong evidence to speculate the action of AChE is on the cells of enamel organ during tooth development.

  16. Concentration distribution and slip velocity of coarse-particle-water mixture in horizontal and inclined pipe sections

    OpenAIRE

    Vlasák, Pavel

    2017-01-01

    Narrow particle size distribution basalt pebbles of mean particle size 11.5 mm conveyed by water in the pipe sections of different inclination were investigated on an experimental pipe loop of inner diameter D = 100 mm. Mixture flow-behaviour and the concentration distribution were studied in a pipe viewing section and with the application of a gamma-ray densitometer. The study refers to the effect of mixture velocity, overall concentration, and angle of pipe inclination on chord-averaged con...

  17. Structures in the Milky Way’s Halo System using the Age Distribution of Field Horizontal-Branch Stars

    Science.gov (United States)

    Lentner, Geoffrey; Beers, Timothy C.; Placco, Vinicius M.; Carollo, Daniela; Whitten, Deven; Denissenkov, Pavel; Santucci, Rafael; Rossi, Silvia

    2017-01-01

    Twenty five years ago it was demonstrated that the colors of blue horizontal-branch (BHB) stars in the halo of the Milky Way correlate with age (Preston et al., 1991). More recently, this property of BHB stars has been used to construct chronographic (age) maps of the Galaxy (Santucci et al., 2015; Carollo et al., 2016), which revealed the presence of substructures on the basis of the age contrast between younger accreted satellites with respect to the diffuse halo field stars, and, for the first time, obtained an empirical estimate of the age gradient for the halo of the Galaxy based on field BHB stars. These maps also indicated the presence of an ancient chronographic sphere, including the oldest BHB stars, extending from close to the Galactic center out to some 10-15 kpc.We extend these studies making use of deeper u-band photometry from the recent public data release of the SCUSS survey (Zou et al., 2016). We also describe application of a new grid of ages that takes into account both metallicity and colors for BHB stars.By building deeper chronographic maps we can better explore the age structures that are revealed. Up- coming large surveys, including the public release of Pan-STARRS, as well as photometry from the Dark Energy Survey, will further add to these efforts.This work received partial support from PHY 14-30152; Physics Frontier Center/JINA Center for the Evolution of the Elements (JINA-CEE), awarded by the US National Science Foundation.

  18. Contributions of vertical descent, horizontal transfer and gene loss to the distribution of mycotoxin biosynthetic gene clusters in Fusarium

    Science.gov (United States)

    The genus Fusarium produces a diverse array of mycotoxins and other secondary metabolites, but individual species contribute to only a small fraction of this diversity. Here, we employed comparative genomic and phylogenetic analyses to investigate the distribution and evolution of gene clusters resp...

  19. On the degree distribution of horizontal visibility graphs associated with Markov processes and dynamical systems: diagrammatic and variational approaches

    Science.gov (United States)

    Lacasa, Lucas

    2014-09-01

    Dynamical processes can be transformed into graphs through a family of mappings called visibility algorithms, enabling the possibility of (i) making empirical time series analysis and signal processing and (ii) characterizing classes of dynamical systems and stochastic processes using the tools of graph theory. Recent works show that the degree distribution of these graphs encapsulates much information on the signals' variability, and therefore constitutes a fundamental feature for statistical learning purposes. However, exact solutions for the degree distributions are only known in a few cases, such as for uncorrelated random processes. Here we analytically explore these distributions in a list of situations. We present a diagrammatic formalism which computes for all degrees their corresponding probability as a series expansion in a coupling constant which is the number of hidden variables. We offer a constructive solution for general Markovian stochastic processes and deterministic maps. As case tests we focus on Ornstein-Uhlenbeck processes, fully chaotic and quasiperiodic maps. Whereas only for certain degree probabilities can all diagrams be summed exactly, in the general case we show that the perturbation theory converges. In a second part, we make use of a variational technique to predict the complete degree distribution for special classes of Markovian dynamics with fast-decaying correlations. In every case we compare the theory with numerical experiments.

  20. Effect of Integration Patterns Around Implant Neck on Stress Distribution in Peri-Implant Bone: A Finite Element Analysis.

    Science.gov (United States)

    Han, Jingyun; Sun, Yuchun; Wang, Chao

    2017-08-01

    To investigate the biomechanical performance of different osseointegration patterns between cortical bone and implants using finite element analysis. Fifteen finite element models were constructed of the mandibular fixed prosthesis supported by implants. Masticatory loads (200 N axial, 100 N oblique, 40 N horizontal) were applied. The cortical bone/implant interface was divided equally into four layers: upper, upper-middle, lower-middle, and lower. The bone stress and implant displacement were calculated for 5 degrees of uniform integration (0, 20%, 40%, 60%, and 100%) and 10 integration patterns. The stress was concentrated in the bone margin and gradually decreased as osseointegration progressed, when the integrated and nonintegrated areas were alternated on the bone-implant surface. Compared with full integration, the integration of only the lower-middle layer or lower half layers significantly decreased von Mises, tensile, and compressive stresses in cortical bone under oblique and horizontal loads, and these patterns did not induce higher stress in the cancellous bone. For the integration of only the upper or upper-middle layer, stress in the cortical and cancellous bones significantly increased and was considerably higher than in the case of nonintegration. In addition, the maximum stress in the cortical bone was sensitive to the quantity of integrated nodes at the bone margin; lower quantity was associated with higher stress. There was no significant difference in the displacement of implants among 15 models. Integration patterns of cortical bone significantly affect stress distribution in peri-implant bone. The integration of only the lower-middle or lower half layers helps to increase the load-bearing capacity of peri-implant bone and decrease the risk of overloading, while upper integration may further increase the risk of bone resorption. © 2016 by the American College of Prosthodontists.

  1. Diel horizontal distribution of microcrustaceans and predators throughout a year in a shallow neotropical lake Distribuição horizontal de microcrustáceos e predadores ao longo do ano em um lago neotropical

    Directory of Open Access Journals (Sweden)

    MS. Arcifa

    2013-02-01

    Full Text Available The focus of this study is to investigate if microcrustaceans undergo diel horizontal migration (DHM in a tropical shallow lake on a yearly basis and analyse the adaptive value regarding predation. Abundance of invertebrate predators, chaoborid larvae and water mites, and microcrustaceans (cladocerans and copepods were evaluated on a monthly basis in three stations located on a transect during the day and at night. Both invertebrate predators were predominantly pelagic. Cladocerans did not undergo significant DHM, distributing indistinctly onshore and offshore or being mostly pelagic. Nauplii, copepodites of two copepod species and adults of Tropocyclops prasinus meridionalis Kiefer were mostly distributed offshore, and did not perform DHM. The limnological features (temperature, dissolved oxygen, pH, and conductivity were suitable for the organisms in both zones of the lake. Algal food concentration was a little lower in the littoral than in the limnetic zone during the day, but it seems to be suitable for the organisms. However, as the algae quality was not evaluated, it is not possible to be conclusive concerning its influence. The results indicated that DHM was not performed by the microcrustaceans and is not, therefore, a strategy for decreasing predation by both invertebrates, Chaoborus brasiliensis Theobald and Krendowskia sp., on a yearly basis in this shallow lake.O foco deste estudo é verificar se microcrustáceos apresentam migração horizontal diária (MHD em um lago raso tropical, durante um ano, e o valor adaptativo com relação à predação. A abundância de predadores invertebrados, larvas de caoborídeos e ácaros aquáticos, e de cladóceros e copépodos foi avaliada mensalmente em três estações de coleta localizadas em um transecto, de dia e à noite. Ambos os predadores invertebrados foram predominantemente pelágicos. Os cladóceros não realizaram MHD, distribuindo-se indistintamente nas zonas litorânea e pel

  2. Connectivity of vehicular ad hoc networks with continuous node distribution patterns

    OpenAIRE

    Jin, W L; Wang, Bruce

    2010-01-01

    The connectivity of vehicular ad hoc networks (VANets) can be affected by the special distribution patterns, usually dependent and non-uniform, of vehicles in a transportation network. In this study, we introduce a new framework for computing the connectivity in a VANet for continuous distribution patterns of communication nodes on a line in a transportation network. Such distribution patterns can be estimated from traffic densities obtained through loop detectors or other detectors. When com...

  3. Spatial patterns of zooplankton distribution and abundance in ...

    African Journals Online (AJOL)

    Spatial patterns and abundance of zooplankton in aquatic habitats are important determinants for production of fish species, invertebrates and availability of phytoplankton. Weekly monitoring for zooplankton abundance was conducted in Shirati Bay, Lake Victoria, to explore their spatial patterns in relation to phytoplankton, ...

  4. Recognition of distinctive patterns of gallium-67 distribution in sarcoidosis

    Energy Technology Data Exchange (ETDEWEB)

    Sulavik, S.B.; Spencer, R.P.; Weed, D.A.; Shapiro, H.R.; Shiue, S.T.; Castriotta, R.J. (Univ. of Connecticut School of Medicine, Farmington (USA))

    1990-12-01

    Assessment of gallium-67 ({sup 67}Ga) uptake in the salivary and lacrimal glands and intrathoracic lymph nodes was made in 605 consecutive patients including 65 with sarcoidosis. A distinctive intrathoracic lymph node {sup 67}Ga uptake pattern, resembling the Greek letter lambda, was observed only in sarcoidosis (72%). Symmetrical lacrimal gland and parotid gland {sup 67}Ga uptake (panda appearance) was noted in 79% of sarcoidosis patients. A simultaneous lambda and panda pattern (62%) or a panda appearance with radiographic bilateral, symmetrical, hilar lymphadenopathy (6%) was present only in sarcoidosis patients. The presence of either of these patterns was particularly prevalent in roentgen Stages I (80%) or II (74%). We conclude that simultaneous (a) lambda and panda images, or (b) a panda image with bilateral symmetrical hilar lymphadenopathy on chest X-ray represent distinctive patterns which are highly specific for sarcoidosis, and may obviate the need for invasive diagnostic procedures.

  5. Distribution patterns of the ghost crab Ocypode cursor on sandy ...

    African Journals Online (AJOL)

    The spatial distribution of the ghost crab Ocypode cursor was determined for beaches on eastern Boa Vista Island, Cabo Verde Archipelago. The main objectives were to analyse the across-shore distribution by means of burrow counts and to identify preferential zones and spatial segregation. Six beaches were investigated ...

  6. Distributional patterns of the American Peiratinae (Heteroptera: Reduviidae)

    NARCIS (Netherlands)

    Morrone, J.J.; Coscarón, del C M.

    1996-01-01

    Based on distributional data of 40 species of Peiratinae, historical relationships of five Amazonian areas (Paranaense, Atlantic, Pacific, Amazonian, and Cerrado) and two Chacoan areas (Chaco and Caatinga), were investigated through a parsimony analysis of endemicity (PAE). The resulting area

  7. Spatio-temporal pattern of rainfall distribution over Ilorin metropolis ...

    African Journals Online (AJOL)

    Rainfall varies over time and space and the study of its variability cannot be over emphasized. This paper examines spatio-temporal patterns of rainfall in Ilorin metropolis, Nigeria. 30 years data were collected in 3 locations [Nigeria Meteorological Agency (NIMET), Lower Niger River Basin Development Authority (LNRBDA) ...

  8. Phylogenetic tests of distribution patterns in South Asia: towards an ...

    Indian Academy of Sciences (India)

    Madhu

    In the last few decades, significant progress has been made in this field due to the infusion of phylogenetic systematics* (Crisci et al 2003; Lomolino and Heaney 2004). Phylogenetic analyses allow inferences about the pattern and time scale of divergence between lineages and postulation of historical processes at levels.

  9. Assessment of Dermatoglyphic Patterns and Sex Distribution in ...

    African Journals Online (AJOL)

    This study was carried out to find out the possibility of a unique pattern of palm and finger prints (Dermatoglyphics) among 192 adults (96 males and 96 females) of Esan origin who, at the time of this study, were residing in Esan-land - the central senatorial district of Edo state, Nigeria. The subjects were selected via ...

  10. Distribution of strain patterns in children with dilated cardiomyopathy.

    Science.gov (United States)

    den Boer, Susanna L; du Marchie Sarvaas, Gideon J; Klitsie, Liselotte M; van Iperen, Gabriëlle G; Tanke, Ronald B; Helbing, Willem A; Backx, Ad P C M; Rammeloo, Lukas A J; Dalinghaus, Michiel; Ten Harkel, Arend D J

    2017-06-01

    This study aimed to evaluate the predicting value of quantitative and qualitative dyssynchrony parameters as assessed by two-dimensional speckle tracking echocardiography (STE) on outcome in children with dilated cardiomyopathy (DCM). Furthermore, the reproducibility of these parameters was investigated. In previous studies in adults with heart failure, several dyssynchrony parameters have been shown to be a valuable predictor of clinical outcome. This multicenter, prospective study included 75 children with DCM and 75 healthy age-matched controls. Using STE, quantitative (time to global peak strain and parameters describing intraventricular time differences) and qualitative dyssynchrony parameters (pattern analysis) of the apical four-chamber, three-chamber, two-chamber views, and the short axis of the left ventricle were assessed. Cox regression was used to identify risk factors for the primary endpoints of death or heart transplantation. Inter-observer and intra-observer variability were described. During a median of 21 months follow-up, 10 patients (13%) reached an endpoint. Although quantitative dyssynchrony measures were higher in patients as compared to controls, the inter-observer and intra-observer variability were high. Pattern analysis showed mainly reduced strain, instead of dyssynchronous patterns. In this study, quantitative dyssynchrony parameters were not reproducible, precluding their use in children. Qualitative pattern analysis showed predominantly reduced strain, suggesting that in children with DCM dyssynchrony may be a minor problem. © 2017, Wiley Periodicals, Inc.

  11. Distribution patterns of striped mullet Mugil cephalus in mangrove ...

    African Journals Online (AJOL)

    The density of juvenile mullet differed significantly among the creeks, but the spatial patterns within them were consistent with higher densities upstream in three of ... striped mullet vary among sites and creeks in response to refuge availability from turbid, shallow water and the accessibility of food from benthic microalgae.

  12. Species distribution and antifungal sensitivity patterns of vaginal ...

    African Journals Online (AJOL)

    Objectives: To identify yeast isolates in vaginal specimens to species level and determine their antifungal susceptibility patterns. Design: Cross-sectional laboratory-based study. Setting: The Aga Khan University Hospital (AKUH), Nairobi. Subjects: Yeast isolates from high vaginal swabs presented to the laboratory for ...

  13. Distributional patterns and possible origin of leafhoppers (Homoptera, Cicadellidae

    Directory of Open Access Journals (Sweden)

    Mervin W. Nielson

    2000-03-01

    Full Text Available The zoogeographical distribution of 42 cicadellid subfamilies and their assigned tribes and genera is compiled with distributional maps and proposed dispersal pathways of genera that are shared interzoogeographically. Possible origin of the subfamilies and tribes is proposed in an ancestral context from which the more modern extant groups evolved whereas origin of genera is in a more modern context. Notwithstanding their complex biogeography, the distributional data of the higher groups indicate that all of the cosmopolitan and near cosmopolitan subfamilies arose during early Cretaceous or possibly the late Jurassic period (140-116 m.y.a. when continental drift was in its early stages. Nearly all of the New World and some Old World subfamilies are considered of more recent origin (late Cretaceous-Tertiary. Ninety percent of the known genera (2,126 are endemic to their respective zoogeographical region and subregion, thus indicating relatively high host specificity and low rate of dispersal. The majority (76% of known extant genera are pantropical in origin, suggesting early or possible Gondwanaland origin of their ancestors. Dispersal pathways of genera shared by more than one zoogeographical region were generally south to north (Neotropical/Nearctic, Oriental/Palaearctic or west to east (Palaearctic/Nearctic, Oriental/Australian, from regions of high diversity to regions of low diversity and from warmer climates to cooler climates. The most diverse and richest leafhopper fauna are present in the Neotropical and Ethiopian regions although taxal affinities between them are poorest. The most depauperate fauna are in the Nearctic region and in Australia, reflecting the impact of isolating and ecological factors on distribution and radiation. Ecological barriers were more evident between the Ethiopian and Oriental fauna than between any other zoogeographical combination. Taxal affinities appeared to be correlated with close continental proximities

  14. Spatial patterns of distribution and abundance of Harrisia portoricensis, an endangered Caribbean cactus

    Science.gov (United States)

    J. Rojas-Sandoval; E. J. Melendez-Ackerman; NO-VALUE

    2013-01-01

    Aims The spatial distribution of biotic and abiotic factors may play a dominant role in determining the distribution and abundance of plants in arid and semiarid environments. In this study, we evaluated how spatial patterns of microhabitat variables and the degree of spatial dependence of these variables influence the distribution and abundance of the endangered...

  15. Business Pattern of Distributed Energy in Electric Power System Reformation

    Science.gov (United States)

    Liang, YUE; Zhuochu, LIU; Jun, LI; Siwei, LI

    2017-05-01

    Under the trend of the electric power system revolution, the operation mode of micro power grid that including distributed power will be more diversified. User’s demand response and different strategies on electricity all have great influence on the operation of distributed power grid. This paper will not only research sensitive factors of micro power grid operation, but also analyze and calculate the cost and benefit of micro power grid operation upon different types. Then it will build a tech-economic calculation model, which applies to different types of micro power grid under the reformation of electric power system.

  16. Variation in terminology: capoeira in Belo Horizonte

    Directory of Open Access Journals (Sweden)

    César Nardelli Cambraia

    2014-12-01

    Full Text Available In this pilot study we analyzed the variation in the terminology of capoeira in Belo Horizonte. The terms referring to 69 videotaped movements of capoeira were collected from 10 informants (5 men and 5 women, aged between 25 and 32 years, capoeira teachers. As a result we obtained 294 different terms whose patterns of variation are distributed among 15 types. We tested the hypothesis that the figurative terms tend to be replaced by non-figurative ones, and it was confirmed by the collected data. This trend was the result of a search for transparency in terminology, making the terms more descriptive in relation to capoeira’s movements.

  17. Patterns of distribution and conservation status of freshwater fishes ...

    African Journals Online (AJOL)

    The combined fish collection databases of the Albany Museum and the J.L.B. Smith Institute of Ichthyology are used to identify hotspots of endemism and threatened fish distributions in South Africa. Hotspots of fish species richness occur in the north-eastern lowveld sectors of South Africa and along the ecotone between ...

  18. The effect of spatial planning patterns on distribution of pedestrians ...

    African Journals Online (AJOL)

    Such spaces have consequently failed to fulfill the roles ascribed to them and instead have become neglected and unsafe to operate in. Space syntax and structured observation have been used to collect data. Multiple regression analysis establishes that nine public space variables significantly predict the distribution of ...

  19. Petrology and Rare Earth Elements (REE) distribution patterns of ...

    African Journals Online (AJOL)

    Volcanic and intermediate rocks such as basalts, trachyandesites, trachytes, dacites, rhyolites, nepheline syenites and quartz diorites occur within the area intermittently. The distribution of the chondrite normalized values is used to determine the effect due to magmatic fractionation and the crustal contamination. The REE ...

  20. Ecological patterns, distribution and population structure of Prionace glauca (Chondrichthyes: Carcharhinidae) in the tropical-subtropical transition zone of the north-eastern Pacific.

    Science.gov (United States)

    Vögler, Rodolfo; Beier, Emilio; Ortega-García, Sofía; Santana-Hernández, Heriberto; Valdez-Flores, J Javier

    2012-02-01

    Regional ecological patterns, distribution and population structure of Prionace glauca were analyzed based on samples collected on-board two long-line fleets operating in oceanic waters (1994-96/2000-02) and in coastal oceanic waters (2003-2009) of the eastern tropical Pacific off México. Generalized additive models were applied to catch per unit of effort data to evaluate the effect of spatial, temporal and environmental factors on the horizontal distribution of the life stages (juvenile, adult) and the sexes at the estimated depth of catch. The presence of breeding areas was explored. The population structure was characterized by the presence of juveniles' aggregations and pregnant females towards coastal waters and the presence of adult males' aggregations towards oceanic waters. The species exhibited horizontal segregation by sex-size and vertical segregation by sex. Distribution of the sex-size groups at oceanic waters was seasonally affected by the latitude; however, at coastal oceanic waters mainly females were influenced by the longitude. Latitudinal changes on the horizontal distribution were coupled to the seasonal forward and backward of water masses through the study area. Adult males showed positive relationship with high temperatures and high-salinities waters (17.0°-20.0 °C; 34.2-34.4) although they were also detected in low-salinities waters. The distribution of juvenile males mainly occurred beyond low temperatures and low-salinities waters (14.0°-15.0 °C; 33.6-34.1), suggesting a wide tolerance of adult males to explore subartic and subtropical waters. At oceanic areas, adult females were aggregated towards latitudes distribution of juvenile females indicated its preference by lower temperatures and more saline waters. Presence of pregnant females suggests that the eastern tropical Pacific off México represents an ecological key region to the reproductive cycle of P. glauca. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Distribution of tetracycline resistance genes in anaerobic treatment of waste sludge: The role of pH in regulating tetracycline resistant bacteria and horizontal gene transfer.

    Science.gov (United States)

    Huang, Haining; Chen, Yinguang; Zheng, Xiong; Su, Yinglong; Wan, Rui; Yang, Shouye

    2016-10-01

    Although pH value has been widely regarded as an important factor that affects resource recovery of waste sludge, the potential influence of diverse pHs on the distribution of tetracycline resistance genes (TRGs) during sludge anaerobic treatment is largely unknown. Here we reported that in the range of pH 4-10, 0.58-1.18 log unit increase of target TRGs was observed at pH 4, compared with that at pH 7, while 0.70-1.31 log unit further removal were obtained at pH 10. Mechanism study revealed that varied pHs not only altered the community structures of tetracycline resistant bacteria (TRB), but also changed their relative abundances, benefitting the propagation (acidic pHs) or attenuation (alkaline pHs) of TRB. Further investigation indicated that the amount and gene-possessing abilities of key genetic vectors for horizontal TRGs transfer were greatly promoted at acidic pHs but restricted under alkaline conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Depth distribution of preferential flow patterns in a sandy loam soil as affected by tillage

    Directory of Open Access Journals (Sweden)

    C. T. Petersen

    1997-01-01

    Full Text Available Dye-tracer studies using the anionic dye Brilliant Blue FCF were conducted on a structured sandy loam soil (Typic Agrudalf. 25 mm of dye solution was applied to the surface of 11 1.6 x 1.6 m field plots, some of which had been subjected to conventional seed bed preparation (harrowing while others had been rotovated to either 5 or 15 cm depth before sowing. The soil was excavated to about 160 cm depth one or two days after dye application. Flow patterns and structural features appearing on vertical or horizontal cross sections were examined and photographed. The flow patterns were digitized, and depth functions for the number of activated flow pathways and the degree of dye coverage were calculated. Dye was found below 100 cm depth on 26 out of 33 vertical cross sections made in conventionally tilled plots showing that preferential flow was a prevailing phenomenon. The depth-averaged number of stained flow pathways in the 25-100 cm layer was significantly smaller in a plot rotovated to 5 cm depth than in a conventionally tilled plot, both under relatively dry initial soil conditions and when the entire soil profiles were initially at field capacity. There were no examples of dye penetration below 25 cm depth one month after deep rotovation. Distinct horizontal structures in flow patterns appearing at 20-40 cm depth coupled with changes in flow domains indicated soil layering with abrupt changes in soil structure and hydraulic properties.

  3. Distribution patterns of postmortem damage in human mitochondrial DNA

    DEFF Research Database (Denmark)

    Gilbert, M Thomas P; Willerslev, Eske; Hansen, Anders J

    2002-01-01

    The distribution of postmortem damage in mitochondrial DNA retrieved from 37 ancient human DNA samples was analyzed by cloning and was compared with a selection of published animal data. A relative rate of damage (rho(v)) was calculated for nucleotide positions within the human hypervariable region......, such as MT5, have lower in vivo mutation rates and lower postmortem-damage rates. The postmortem data also identify a possible functional subregion of the HVR1, termed "low-diversity 1," through the lack of sequence damage. The amount of postmortem damage observed in mitochondrial coding regions...

  4. Income distribution patterns from a complete social security database

    CERN Document Server

    Derzsy, N; Santos, M A

    2012-01-01

    We analyze the income distribution of employees for 9 consecutive years (2001-2009) using a complete social security database for an economically important district of Romania. The database contains detailed information on more than half million taxpayers, including their monthly salaries from all employers where they worked. Besides studying the characteristic distribution functions in the high and low/medium income limits, the database allows us a detailed dynamical study by following the time-evolution of the taxpayers income. To our knowledge, this is the first extensive study of this kind (a previous japanese taxpayers survey was limited to two years). In the high income limit we prove once again the validity of Pareto's law, obtaining a perfect scaling on four orders of magnitude in the rank for all the studied years. The obtained Pareto exponents are quite stable with values around $\\alpha \\approx 2.5$, in spite of the fact that during this period the economy developed rapidly and also a financial-econ...

  5. EFFECT OF COST INCREMENT DISTRIBUTION PATTERNS ON THE PERFORMANCE OF JIT SUPPLY CHAIN

    Directory of Open Access Journals (Sweden)

    Ayu Bidiawati J.R

    2008-01-01

    Full Text Available Cost is an important consideration in supply chain (SC optimisation. This is due to emphasis placed on cost reduction in order to optimise profit. Some researchers use cost as one of their performance measures and others propose ways of accurately calculating cost. As product moves across SC, the product cost also increases. This paper studied the effect of cost increment distribution patterns on the performance of a JIT Supply Chain. In particular, it is necessary to know if inventory allocation across SC needs to be modified to accommodate different cost increment distribution patterns. It was found that funnel is still the best card distribution pattern for JIT-SC regardless the cost increment distribution patterns used.

  6. Uniform pattern of normal faulting at the temporally distributed centers of eruption along the path of the Yellowstone hotspot

    Science.gov (United States)

    Davarpanah, Armita; Babaie, Hassan

    2016-04-01

    The northeasterly migration of the Yellowstone hotspot (YHS) has led both to the successive eruption of lava from a temporally ordered set of calderas, and related thermally-induced normal faulting along the Snake River Plain (SRP) over the past 16.6 Ma. We have applied a series of structural and statistical methods to analyze the spatial distribution and orientation of the normal faults to understand the kinematics of the mid-Tertiary-Quaternary faulting event along the SRP in the northern Rockies. The azimuths of the linear directional mean (LDM) and the directional (autocorrelation) anisotropy ellipses in the semivariograms, applying Ordinary Kriging, for different sets of normal fault traces give an estimate for the horizontal component of extension for normal faulting. The sub-parabolic spatial pattern of the normal fault LDMs, and their sub-parallel alignment with the minor axes of the Standard Deviation Ellipses (SDEs) in and around different caldera, suggest uniform normal faulting during thermally-induced extensions along the SRP. The asymmetric, sub-parabolic distribution of the spatial trajectories (form lines) of the LDMs and the major axes of the directional (anisotropy) ellipses of the traces of normal faults in the youngest three calderas are similar to the reported parabolic distribution of earthquake epicenters along active normal faults around the YHS. The parallelism of the axis of the sub-parabolic pattern with the trajectories of the LDMs, the major axes of the directional anisotropy ellipses, and the deduced extension directions for each caldera, suggest systematic and progressive normal faulting due to the thermal regime of the hotspot as it migrated to the northeast. This implies that the age of normal faulting progressively decreases to the northeast.

  7. Seasonal and distributional patterns of seabirds along the Aleutian Archipelago

    Science.gov (United States)

    Renner, M.; Hunt, G.L.; Piatt, John F.; Byrd, G.V.

    2008-01-01

    The Aleutian Archipelago is of global importance to seabirds during the northern summer, but little is known about seabird use of these waters during winter. We compare summer and winter abundances of seabirds around 3 islands: Buldir in the western, Kasatochi in the central, and Aiktak in the eastern Aleutians. The density of combined seabird biomass in nearshore marine waters was higher in summer than in winter at Buldir and Kasatochi, but was higher in winter at Aiktak, despite the departure of abundant migratory species. Comparing foraging guilds, we found that only piscivores increased at the western and central sites in winter, whereas at the eastern site several planktivorous species increased as well. The only planktivore remaining in winter at the central and western sites in densities comparable to summer densities was whiskered auklet Aethia pygmaea. Crested auklet Aethia cristatella and thick-billed murre Uria lomvia showed the greatest proportional winter increase at the eastern site. The seasonal patterns of the seabird communities suggest a winter breakdown of the copepod-based food web in the central and western parts of the archipelago, and a system that remains rich in euphausiids in the eastern Aleutians. We suggest that in winter crested auklets take the trophic role that short-tailed shearwaters Puffinus tenuirostris occupy during summer. We hypothesize that advection of euphausiids in the Aleutian North Slope Current is important for supporting the high biomass of planktivores that occupy the Unimak Pass region on a year-round basis. ?? Inter-Research 2008.

  8. Distribution patterns of invasive alien species in Alabama, USA

    Directory of Open Access Journals (Sweden)

    Xiongwen Chen

    2012-12-01

    Full Text Available Invasive alien species (IAS cause environmental and economical problems. How to effectively manage all IAS at a large area is a challenge.Hypotheses about IAS (such as the “human activity” hypothesis, the “biotic acceptance” and the “biotic resistance” have been proposedfrom numerous studies. Here the state of Alabama in USA, widely occupied by IAS, is used as a case study for characterizing the emergentpatterns of IAS. The results indicate that most IAS are located in metropolitan areas and in the Black Belt area which is a historical intensiveland use area. There are positive relationships between the richness of IAS and the change of human population, the species richness and thenumber of endangered species, as well as the total road length and farmland area across Alabama. This study partially supports the abovethree hypotheses and provides a general pattern of local IAS. Based on possible processes related with IAS, some implications forstrategically managing local IAS are discussed.

  9. Tree species exhibit complex patterns of distribution in bottomland hardwood forests

    Science.gov (United States)

    Luben D Dimov; Jim L Chambers; Brian R. Lockhart

    2013-01-01

    & Context Understanding tree interactions requires an insight into their spatial distribution. & Aims We looked for presence and extent of tree intraspecific spatial point pattern (random, aggregated, or overdispersed) and interspecific spatial point pattern (independent, aggregated, or segregated). & Methods We established twelve 0.64-ha plots in natural...

  10. A Study of Thumb Print Patterns and ABO Blood Group Distribution ...

    African Journals Online (AJOL)

    The aim of this study was to establish a possible relationship between thumb print pattern and ABO blood group distribution. The study involves two hundred and nine-two volunteers comprising 159 female and 133 male. The blood group and finger print patterns were determined using standard techniques. Results ...

  11. The distribution pattern of Hirneola auricula-judae in the Netherlands

    NARCIS (Netherlands)

    Laan, van der H.F.

    1976-01-01

    The distribution pattern of Hirneola auricula-judae in the Netherlands is discussed. At first this pattern was thought to be mainly determined by the average daily minimum temperatures in winter; high population densities correlating with high winter temperatures. The curve which best fits the data

  12. [Relations between reward-distribution patterns and distribution strategies: how five-year-old children distribute rewards].

    Science.gov (United States)

    Tsutsu, Kiyomi

    2013-08-01

    The relationship between children's reward-distribution judgments and their distribution strategies was investigated. Five-year-old children (N = 61) were presented with two stories where two characters made different numbers of origami stars. The children were asked to distribute different numbers of rewards to the characters: equal to (Middle-N), less than (Small-N), or more than (Large-N) the total number of stars in each story. Distribution strategies were categorized into two types: One-round, where rewards were distributed in one round only, and Cyclic, where the rewards were distributed in several cycles across the characters. In the Small-N of both stories (4 or 8 rewards), most children distributed rewards equally. When the number of rewards was 4, more than half used the One-round strategy, but when it was 8, more than half used the Cyclic strategy. In the Middle-N and Large-N conditions, most equal distributions used the Cyclic strategy, whereas almost all the proportional-equity distributions were associated with the One-round strategy, and most ordinal-equity distributions used the Cyclic strategy. The relationships between automatic/controlled reward-distribution judgments and distribution strategies were discussed.

  13. Tardigrades of Alaska: distribution patterns, diversity and species richness

    Directory of Open Access Journals (Sweden)

    Carl Johansson

    2013-05-01

    Full Text Available During the summer of 2010, a biotic survey of tardigrades was conducted along a latitudinal transect in central Alaska from the Kenai Peninsula, via Fairbanks and the Arctic Circle to the coastal plain. Work was centred at the Toolik and Bonanza Creek Long Term Ecological Research Network sites and supplemented by opportunistic collections from the Kenai Peninsula and Anchorage areas. The 235 samples collected at 20 sites over 10 degrees of latitude yielded 1463 tardigrades representing two classes, three orders, 10 families, 23 genera and 73 species from 142 positive samples. A total of 50 species are new to Alaska, increasing the state's known species richness to 84. Several environmental metrics, such as pH, substrate, elevation, location and habitat were measured, recorded and analysed along the latitudinal gradient. Contrary to expectations, pH did not appear to be a predictor of tardigrade abundance or distribution. Density and species richness were relatively consistent across sites. However, the assemblages were highly variable within and between sites at only 14–20% similarity. We detected no correlation between species diversity and latitudinal or environmental gradients, though this may be affected by a high (59.9% occurrence of single-species samples (containing individuals of only one species. Estimates of species richness were calculated for Alaska (118 and the Arctic (172. Our efforts increased the number of known species in Alaska to 84, and those results led us to question the validity of the estimate numbers.

  14. Distributed dynamical computation in neural circuits with propagating coherent activity patterns.

    Directory of Open Access Journals (Sweden)

    Pulin Gong

    2009-12-01

    Full Text Available Activity in neural circuits is spatiotemporally organized. Its spatial organization consists of multiple, localized coherent patterns, or patchy clusters. These patterns propagate across the circuits over time. This type of collective behavior has ubiquitously been observed, both in spontaneous activity and evoked responses; its function, however, has remained unclear. We construct a spatially extended, spiking neural circuit that generates emergent spatiotemporal activity patterns, thereby capturing some of the complexities of the patterns observed empirically. We elucidate what kind of fundamental function these patterns can serve by showing how they process information. As self-sustained objects, localized coherent patterns can signal information by propagating across the neural circuit. Computational operations occur when these emergent patterns interact, or collide with each other. The ongoing behaviors of these patterns naturally embody both distributed, parallel computation and cascaded logical operations. Such distributed computations enable the system to work in an inherently flexible and efficient way. Our work leads us to propose that propagating coherent activity patterns are the underlying primitives with which neural circuits carry out distributed dynamical computation.

  15. Diffraction patterns from holographic masks generated using combined axicon and helical phase distributions

    Science.gov (United States)

    Mihailescu, M.; Preda, L.; Kusko, C.; Scarlat, E. I.

    2015-02-01

    The diffraction patterns (DPs) from helical phase distributions were intensively studied due to their peculiar capability of carrying orbital angular momentum. In the present study, we investigated the combination between a helical phase distribution and another distribution: axicon in our case. Such phase distributions were digitally embedded into holographic masks (HMs). The reconstruction step is performed by simulating the propagation through these HMs, using scalar diffraction theory, Fraunhofer approximation. The spatial intensity arrangement of the DPs is investigated linked with the radial and azimuthal constructive parameters values of the diffractive phase structures embedded in the HMs and transferred in these DPs. Keywords: helical phase distribution

  16. Patterns of distribution of childhood cancer in Africa.

    Science.gov (United States)

    Stefan, D Cristina

    2015-06-01

    Very little is known about the regional variation in the incidence of childhood malignancies in Africa. The aim of the study was to perform a comprehensive analysis of the distribution of childhood cancer in Sub-Saharan Africa and compare the results to the Globocan estimations. A letter of invitation to participate was sent to all registry centers in Africa registered with the International Agency for Research on Cancer and to all African centers registered with AORTIC and SIOP Africa, requesting similar information as in CanReg 4. Childhood cancers were defined as those occurring below the age of 15 years. The data requested was from 2000 to 2010. The malignancies were classified and coded according to the International Classification of Childhood Cancer, 2004 system. Data obtained were analyzed using EpiInfo and Statistica 10 software. Information regarding the estimation of the numbers and incidence of the top 5 childhood cancers in specific countries was obtained from Globocan Web site. There were 21 centers included in the study from 18 Sub-Saharan African countries. The data analyzed differed from center to center and included cases from 1985 to 2011. The proportion of childhood cancer out of all cancers ranged between 1.4% in Ghana to 10.0% in Rwanda. In Southern Africa, Kaposi sarcoma was the most common malignancy in children in Mozambique (15.8% of all cases) and the second most common in Zambia (15.6%) and in Malawi (12.4%). In Eastern Africa, Uganda recorded Kaposi sarcoma as the most common tumor in children (22.0%), while two Kenyan centers reported mainly Burkitt lymphoma (25.1 and 37.1%, respectively). In Central Africa, Congo classified retinoblastoma as the most common childhood cancer with an incidence of 20.1%. In Western Africa, Non-Hodgkin lymphoma was the most common in Ghana (53.6%), in Ivory Coast (73.6%) and in Mali (32.7%). Nephroblastoma remains the most common solid tumor in Africa exceeding 10% of total pediatric cancers in many

  17. The Analysis of Tree Species Distribution Information Extraction and Landscape Pattern Based on Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Yi Zeng

    2017-08-01

    Full Text Available The forest ecosystem is the largest land vegetation type, which plays the role of unreplacement with its unique value. And in the landscape scale, the research on forest landscape pattern has become the current hot spot, wherein the study of forest canopy structure is very important. They determines the process and the strength of forests energy flow, which influences the adjustments of ecosystem for climate and species diversity to some extent. The extraction of influencing factors of canopy structure and the analysis of the vegetation distribution pattern are especially important. To solve the problems, remote sensing technology, which is superior to other technical means because of its fine timeliness and large-scale monitoring, is applied to the study. Taking Lingkong Mountain as the study area, the paper uses the remote sensing image to analyze the forest distribution pattern and obtains the spatial characteristics of canopy structure distribution, and DEM data are as the basic data to extract the influencing factors of canopy structure. In this paper, pattern of trees distribution is further analyzed by using terrain parameters, spatial analysis tools and surface processes quantitative simulation. The Hydrological Analysis tool is used to build distributed hydrological model, and corresponding algorithm is applied to determine surface water flow path, rivers network and basin boundary. Results show that forest vegetation distribution of dominant tree species present plaque on the landscape scale and their distribution have spatial heterogeneity which is related to terrain factors closely. After the overlay analysis of aspect, slope and forest distribution pattern respectively, the most suitable area for stand growth and the better living condition are obtained.

  18. Spatial pattern of 2009 dengue distribution in Kuala Lumpur using GIS application.

    Science.gov (United States)

    Aziz, S; Ngui, R; Lim, Y A L; Sholehah, I; Nur Farhana, J; Azizan, A S; Wan Yusoff, W S

    2012-03-01

    In the last few years in Malaysia, dengue fever has increased dramatically and has caused huge public health concerns. The present study aimed to establish a spatial distribution of dengue cases in the city of Kuala Lumpur using a combination of Geographic Information System (GIS) and spatial statistical tools. Collation of data from 1,618 dengue cases in 2009 was obtained from Kuala Lumpur City Hall (DBKL). These data were processed and then converted into GIS format. Information on the average monthly rainfall was also used to correlate with the distribution pattern of dengue cases. To asses the spatial distribution of dengue cases, Average Nearest Neighbor (ANN) Analysis was applied together with spatial analysis with the ESRI ArcGIS V9.3 programme. Results indicated that the distribution of dengue cases in Kuala Lumpur for the year 2009 was spatially clustered with R value less than 1 (R = 0.42; z-scores = - 4.47; p 1) between August and November. In addition, the mean monthly rainfall has not influenced the distribution pattern of the dengue cases. Implementation of control measures is more difficult for dispersed pattern compared to clustered pattern. From this study, it was found that distribution pattern of dengue cases in Kuala Lumpur in 2009 was spatially distributed (dispersed or clustered) rather than cases occurring randomly. It was proven that by using GIS and spatial statistic tools, we can determine the spatial distribution between dengue and population. Utilization of GIS tools is vital in assisting health agencies, epidemiologist, public health officer, town planner and relevant authorities in developing efficient control measures and contingency programmes to effectively combat dengue fever.

  19. Formal Verification of Architectural Patterns in Support of Dependable Distributed Systems

    Science.gov (United States)

    2005-07-01

    JUL 2005 2. REPORT TYPE 3. DATES COVERED 00-00-2005 to 00-00-2005 4. TITLE AND SUBTITLE Extended Abstract: Formal Verification of Architectural...Rev. 8-98) Prescribed by ANSI Std Z39-18 Extended Abstract: Formal Verification of Architectural Patterns in Support of Dependable Distributed...itd.nrl.navy.mil Keywords: Architectural patterns, dependable software, component-based development, formal verification . 1. Introduction Building

  20. [Spatial distribution patterns of adult population of Pseudorobitis gibbus (Coleoptera: Apionidae) in Taixing Garden, Tai'an, Shandong, China].

    Science.gov (United States)

    Li, Yan; Zheng, Fang-Qiang; Yu, Li-Ying; Qiao, Lu-Qin; Lu, Xi-Ping

    2014-01-01

    The vertical and horizontal distributions of Pseudorobitis gibbus adults on Lagerstroemia indica were analyzed by using the aggregation indices and geostatistics. The results from aggregation index methods indicated that its vertical distribution was an aggregated distribution, and the aggregation average (lambda) was above two, showing that the aggregation resulted from its bionomics and behaviors, not from the environmental factors. The results of geostatistic analysis showed that the best fitting models for the five different sampling data in June 4, June 16, June 29, July 25 and August 22 were Gaussian, Gaussian, Linear, Gaussian and Linear models, respectively, but random models in July 12 and August 7. It was concluded that the horizontal distribution of the pest was aggregated on the whole, and there existed a spatial correlation ranging from 1.68 to 9.79 m on the different dates.

  1. The intestinal distribution pattern of appetite- and glucose regulatory peptides in mice, rats and pigs

    DEFF Research Database (Denmark)

    Albrechtsen, Nicolai Jacob Wewer; Kuhre, Rune Ehrenreich; Toräng, Signe

    2016-01-01

    in mice (n = 9), rats (n = 9) and pigs (n = 8), using validated radioimmunoassays. RESULTS: GLP-1, GLP-2 and oxyntomodulin/glicentin show similar patterns of distribution within the respective species, but for rats and pigs the highest levels were found in the distal small intestine, whereas for the mouse...... in all three species. Most surprisingly, in the pig PYY was found in large amounts in the proximal part of the small intestine whereas both rats and mice had undetectable levels until the distal small intestine. CONCLUSIONS: In summary, the distribution patterns of extractable GIP, GLP-1, GLP-2...

  2. The numerical model of the sediment distribution pattern at Lampulo National fisheries port

    Science.gov (United States)

    Irham, M.; Setiawan, I.

    2018-01-01

    The spatial distribution of sediment pattern was studied at Lampulo Fisheries Port, Krueng Aceh estuarial area, Banda Aceh. The research was conducted using the numerical model of wave-induced currents at shallow water area. The study aims to understand how waves and currents react to the pattern of sediment distribution around the beach structure in that region. The study demonstrated that the port pool area had no sedimentation and erosion occurred because the port was protected by the jetty as the breakwater to defend the incoming waves toward the pool. The protected pool created a weak current circulation to distribute the sediments. On the other hand, the sediments were heavily distributed along the beach due to the existence of longshore currents near the shoreline (outside the port pool area). Meanwhile, at the estuarial area, the incoming fresh water flow responded to the coastal shallow water currents, generating Eddy-like flow at the mouth of the river.

  3. Sediment-hosted contaminants and distribution patterns in the Mississippi and Atchafalaya River Deltas

    Science.gov (United States)

    Flocks, James G.; Kindinger, Jack G.; Ferina, Nicholas; Dreher, Chandra

    2002-01-01

    The Mississippi and Atchafalaya Rivers transport very large amounts of bedload and suspended sediments to the deltaic and coastal environments of the northern Gulf of Mexico. Absorbed onto these sediments are contaminants that may be detrimental to the environment. To adequately assess the impact of these contaminants it is first necessary to develop an understanding of sediment distribution patterns in these deltaic systems. The distribution patterns are defined by deltaic progradational cycles. Once these patterns are identified, the natural and industrial contaminant inventories and their depositional histories can be reconstructed. Delta progradation is a function of sediment discharge, as well as channel and receiving-basin dimensions. Fluvial energy controls the sediment distribution pattern, resulting in a coarse grained or sandy framework, infilled with finer grained material occupying the overbank, interdistributary bays, wetlands and abandoned channels. It has been shown that these fine-grained sediments can carry contaminants through absorption and intern them in the sediment column or redistribute them depending on progradation or degradation of the delta deposit. Sediment distribution patterns in delta complexes can be determined through high-resolution geophysical surveys and groundtruthed with direct sampling. In the Atchafalaya and Mississippi deltas, remote sensing using High-Resolution Single-Channel Seismic Profiling (HRSP) and Sidescan Sonar was correlated to 20-ft vibracores to develop a near-surface geologic framework that identifies variability in recent sediment distribution patterns. The surveys identified bedload sand waves, abandoned-channel back-fill, prodelta and distributary mouth bars within the most recently active portions of the deltas. These depositional features respond to changes in deltaic processes and through their response may intern or transport absorbed contaminants. Characterizing these features provides insight into the

  4. Centrifugal spreader mass and nutrients distribution patterns for application of fresh and aged poultry litter.

    Science.gov (United States)

    Temple, W D; Skowrońska, M; Bomke, A A

    2014-06-15

    A spin-type centrifugal spreader was evaluated using fresh and aged poultry litter upon dry mass, product nitrogen (N), phosphorus (P) and potassium (K), incubation study soil available N and particle size distribution patterns. Relative to the aged litter (37% moisture content), the fresh litter (17% moisture content) had greater litter, the broadcast fresh litter resulted in higher coefficients of variation (CV) over its transverse distance, a narrower calculated space distance between passes for uniform spread and lower soil available N concentrations. For nitrogen application over the broadcast transverse distance the fresh litter displayed a high R(2) best fit 4th order polynomial distribution pattern, while the aged litter showed high R(2) best fit 6th order polynomial distribution pattern. A soil incubation study of the fresh and aged broadcast litter resulted in a more variable or lower R(2) best fit 2nd order polynomial distribution pattern. For both the fresh and aged litter, the calculated distance between passes to achieve a uniform mass distribution was greater than that required for the broadcast of soil available N. For the fresh litter, the soil available N and litter P concentration levels strongly correlated (relatively high p and R(2) values) with the litter this relationship was not as significant. In addition to reducing the health risk (i.e. pathogens, antibiotic residues and resistant bacteria) and/or environment issues (particulate fallout onto waterways, adjacent fields and/or residences) our study mass, particulate and N distribution patterns results suggest that poultry litter should be allowed to age before broadcast application is attempted. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Water Breakthrough Shape Description of Horizontal Wells in Bottom-Water Reservoir

    Directory of Open Access Journals (Sweden)

    Shijun Huang

    2014-01-01

    Full Text Available Horizontal wells have been applied in bottom-water reservoir since their advantages were found on distribution of linear dropdown near wellbore, higher critical production, and more OOIP (original oil in place controlled. In the paper, one 3D visible physical model of horizontal physical model is designed and built to simulate the water cresting process during the horizontal well producing and find water breakthrough point in homogenous and heterogeneous reservoir with bottom water. Water cresting shape and water cut of horizontal well in between homogenous and heterogeneous reservoir are compared on the base of experiment’s result. The water cresting pattern of horizontal well in homogeneous reservoir can be summarized as “central breakthrough, lateral expansion, thorough flooding, and then flank uplifting.” Furthermore, a simple analysis model of horizontal well in bottom water reservoir is established and water breakthrough point is analyzed. It can be drawn from the analysis result that whether or not to consider the top and bottom border, breakthrough would be located in the middle of horizontal segment with equal flow velocity distribution.

  6. Distribution patterns of shallow water polychaetes (Annelida along the Alexandria coast, Egypt (eastern Mediterranean

    Directory of Open Access Journals (Sweden)

    M. M. DORGHAM

    2014-10-01

    Full Text Available Shallow hard bottom and intertidal soft bottom polychaete assemblages of the Alexandria coast, southeastern Mediterranean (Levantine Sea, were studied during a complete annual cycle in order to analyze spatial temporal patterns of variation in assemblages, and relevant factors related to polychaete distribution. The present study recorded a total of 73 species, belonging to Syllidae (22 species, Nereididae (9 species, Serpulidae (6 species, Eunicidae (5 species and other 19 families. The assemblages experienced pronounced spatial and temporal variation throughout the study area, but spatial variation appeared more important in determining the observed patterns. Polychaete distribution related to variation of grain size and sessile macrobenthos cover suggesting that these structural variables accounted more than the physical-chemical ones (namely BOD, dissolved oxygen, organic carbon, organic matter, salinity, temperature, pH in influencing the patterns of assemblages’ distribution. The present study is the southeastern-most one dealing with ecology and distribution patterns of hard bottom polychaetes from the Mediterranean Sea, as well as one of the few studies dealing with intertidal soft bottom polychaetes in the Levant Basin.

  7. Distribution pattern assessment of a dual-purpose disc agrochemical applicator for field crops

    Directory of Open Access Journals (Sweden)

    M. S. Abubakar

    2012-08-01

    Full Text Available A dual-purpose disc agrochemical applicator for field crops was developed to boost agricultural mechanization in crop production and also to overcome the safety concern of hazardous spray drift during agrochemical application by the field crop farmers. The dual purpose agrochemical applicator was mounted on a high clearance tractor and tested with respect to the granular fertilizer distribution patterns uniformity/liquid chemical uniformity of droplet sizes in spraying of the agrochemical. Results for NPK granular chemical indicated that, at low (50 kg/ha and high (150 kg/ha application rates with 550 rpm disc speed, distribution patterns skewed to the left whereas the distribution pattern at medium (100 kg/ha application rates was good flattop. Also at high application rate with 1000 rpm disc speed, mean distribution pattern became poor (W-shape. For the liquid chemical herbicide HC 48 amine liquid, the mean values of volume median diameter (VMD and number median diameter (NMD were 108 µm and 80 µm at 90 lt/ha application rate at 5000 rpm rotary disc speed, and also 344 and 222 µm at 30 lt/ha application rate with 2000 rpm rotary disc speed. The mean values of coefficient of uniformity for droplet sizes expressed as VMD/NMD found in this study were in the range of 1.35 to 1.55 for HC amine 48 liquid chemical.

  8. An Algorithm to Compute the Character Access Count Distribution for Pattern Matching Algorithms

    NARCIS (Netherlands)

    T. Marschall (Tobias); S. Rahmann (Sven)

    2011-01-01

    textabstractWe propose a framework for the exact probabilistic analysis of window-based pattern matching algorithms, such as Boyer--Moore, Horspool, Backward DAWG Matching, Backward Oracle Matching, and more. In particular, we develop an algorithm that efficiently computes the distribution of a

  9. Distribution patterns of medicinal plants along an elevational gradient in central Himalaya, Nepal

    Czech Academy of Sciences Publication Activity Database

    Rokaya, Maan Bahadur; Münzbergová, Zuzana; Shrestha, M.R.; Timsina, B.

    2012-01-01

    Roč. 9, č. 2 (2012), s. 201-213 ISSN 1672-6316 R&D Projects: GA ČR GA526/09/0549 Institutional research plan: CEZ:AV0Z60050516 Keywords : distribution patterns * medicinal plants * unimodal relationships Subject RIV: EF - Botanics Impact factor: 0.664, year: 2012

  10. Pattern and spatial distribution of plague in Lushoto, north-eastern ...

    African Journals Online (AJOL)

    A review of plague records from 1986 to 2002 and household interviews were carried out in the plague endemic villages to establish a pattern and spatial distribution of the disease in Lushoto district, Tanzania. Spatial data of households and village centres were collected and mapped using a hand held Global Positioning ...

  11. Distribution patterns of terrestrial mammals in KwaZulu-Natal | Rowe ...

    African Journals Online (AJOL)

    Distribution patterns, plotted by eighth-degree squares (7.5' x 7.5'), of the 162 mammal species recorded in the province of KwaZulu-Natal, South Africa were examined in relation to the combined factors of vegetation type, climate, and altitude (= bioregions); and in relation to protected areas within the nine bioregions.

  12. Pattern of hair distribution on the dorsal phalanges of the hand in ...

    African Journals Online (AJOL)

    Background: The distribution of hair in the dorsal aspect of the hand digits were investigated in this study. Aim: To determine dorsal phalengeal hair pattern in an African ethnic group. Methods: The study involved 160 male and 140 female of Urhobo volunteers whose ages ranged between 18 and 38 years. Results: Hair ...

  13. Spatial Distribution Characteristics of Healthcare Facilities in Nanjing: Network Point Pattern Analysis and Correlation Analysis.

    Science.gov (United States)

    Ni, Jianhua; Qian, Tianlu; Xi, Changbai; Rui, Yikang; Wang, Jiechen

    2016-08-18

    The spatial distribution of urban service facilities is largely constrained by the road network. In this study, network point pattern analysis and correlation analysis were used to analyze the relationship between road network and healthcare facility distribution. The weighted network kernel density estimation method proposed in this study identifies significant differences between the outside and inside areas of the Ming city wall. The results of network K-function analysis show that private hospitals are more evenly distributed than public hospitals, and pharmacy stores tend to cluster around hospitals along the road network. After computing the correlation analysis between different categorized hospitals and street centrality, we find that the distribution of these hospitals correlates highly with the street centralities, and that the correlations are higher with private and small hospitals than with public and large hospitals. The comprehensive analysis results could help examine the reasonability of existing urban healthcare facility distribution and optimize the location of new healthcare facilities.

  14. Integrating satellite actual evapotranspiration patterns into distributed model parametrization and evaluation for a mesoscale catchment

    Science.gov (United States)

    Demirel, M. C.; Mai, J.; Stisen, S.; Mendiguren González, G.; Koch, J.; Samaniego, L. E.

    2016-12-01

    Distributed hydrologic models are traditionally calibrated and evaluated against observations of streamflow. Spatially distributed remote sensing observations offer a great opportunity to enhance spatial model calibration schemes. For that it is important to identify the model parameters that can change spatial patterns before the satellite based hydrologic model calibration. Our study is based on two main pillars: first we use spatial sensitivity analysis to identify the key parameters controlling the spatial distribution of actual evapotranspiration (AET). Second, we investigate the potential benefits of incorporating spatial patterns from MODIS data to calibrate the mesoscale Hydrologic Model (mHM). This distributed model is selected as it allows for a change in the spatial distribution of key soil parameters through the calibration of pedo-transfer function parameters and includes options for using fully distributed daily Leaf Area Index (LAI) directly as input. In addition the simulated AET can be estimated at the spatial resolution suitable for comparison to the spatial patterns observed using MODIS data. We introduce a new dynamic scaling function employing remotely sensed vegetation to downscale coarse reference evapotranspiration. In total, 17 parameters of 47 mHM parameters are identified using both sequential screening and Latin hypercube one-at-a-time sampling methods. The spatial patterns are found to be sensitive to the vegetation parameters whereas streamflow dynamics are sensitive to the PTF parameters. The results of multi-objective model calibration show that calibration of mHM against observed streamflow does not reduce the spatial errors in AET while they improve only the streamflow simulations. We will further examine the results of model calibration using only multi spatial objective functions measuring the association between observed AET and simulated AET maps and another case including spatial and streamflow metrics together.

  15. Patterns of shift in ADC distributions in abdominal tumours during chemotherapy - feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, Kirsteen; Olsen, Oeystein E. [Great Ormond Street Hospital for Children NHS Trust, Radiology Department, London (United Kingdom); Sebire, Neil J. [Great Ormond Street Hospital for Children NHS Trust, Histopathology Department, London (United Kingdom); Anderson, John [Great Ormond Street Hospital for Children NHS Trust, Oncology Department, London (United Kingdom)

    2011-01-15

    Apparent diffusion coefficient (ADC) relates to tissue cellularity, and change in ADC during chemotherapy may be a promising tool for assessing oncological response. To investigate the feasibility of measuring changes in ADC distribution in solid abdominal and pelvic paediatric tumours during chemotherapy, and to assess patterns of change. Consecutive children were included in a prospective observational study. ADC maps were calculated at presentation and following chemotherapy from a diffusion-sensitised sequence. ADC distribution in the whole tumour, excluding areas of low or absent gadolinium-enhancement, was investigated. Change during chemotherapy was assessed for each patient individually. Histopathological slices from the resected specimens were reviewed. There were seven children (nine tumours) included in the study. ADC in all except one deviated from a normal distribution. All tumours changed their ADC distribution during chemotherapy. Median ADC increased in all upper abdominal tumours, but more in tumours with histopathologically good or marked response to chemotherapy. Seven out of nine tumours attained a wider ADC distribution, the remaining two showed little chemotherapy response. ADC distribution changes during chemotherapy in childhood abdominal tumours are measurable. Distinct patterns of shift can be observed and ADC change is therefore promising as a noninvasive biomarker for therapy response. (orig.)

  16. Design pattern mining using distributed learning automata and DNA sequence alignment.

    Directory of Open Access Journals (Sweden)

    Mansour Esmaeilpour

    Full Text Available CONTEXT: Over the last decade, design patterns have been used extensively to generate reusable solutions to frequently encountered problems in software engineering and object oriented programming. A design pattern is a repeatable software design solution that provides a template for solving various instances of a general problem. OBJECTIVE: This paper describes a new method for pattern mining, isolating design patterns and relationship between them; and a related tool, DLA-DNA for all implemented pattern and all projects used for evaluation. DLA-DNA achieves acceptable precision and recall instead of other evaluated tools based on distributed learning automata (DLA and deoxyribonucleic acid (DNA sequences alignment. METHOD: The proposed method mines structural design patterns in the object oriented source code and extracts the strong and weak relationships between them, enabling analyzers and programmers to determine the dependency rate of each object, component, and other section of the code for parameter passing and modular programming. The proposed model can detect design patterns better that available other tools those are Pinot, PTIDEJ and DPJF; and the strengths of their relationships. RESULTS: The result demonstrate that whenever the source code is build standard and non-standard, based on the design patterns, then the result of the proposed method is near to DPJF and better that Pinot and PTIDEJ. The proposed model is tested on the several source codes and is compared with other related models and available tools those the results show the precision and recall of the proposed method, averagely 20% and 9.6% are more than Pinot, 27% and 31% are more than PTIDEJ and 3.3% and 2% are more than DPJF respectively. CONCLUSION: The primary idea of the proposed method is organized in two following steps: the first step, elemental design patterns are identified, while at the second step, is composed to recognize actual design patterns.

  17. Design Pattern Mining Using Distributed Learning Automata and DNA Sequence Alignment

    Science.gov (United States)

    Esmaeilpour, Mansour; Naderifar, Vahideh; Shukur, Zarina

    2014-01-01

    Context Over the last decade, design patterns have been used extensively to generate reusable solutions to frequently encountered problems in software engineering and object oriented programming. A design pattern is a repeatable software design solution that provides a template for solving various instances of a general problem. Objective This paper describes a new method for pattern mining, isolating design patterns and relationship between them; and a related tool, DLA-DNA for all implemented pattern and all projects used for evaluation. DLA-DNA achieves acceptable precision and recall instead of other evaluated tools based on distributed learning automata (DLA) and deoxyribonucleic acid (DNA) sequences alignment. Method The proposed method mines structural design patterns in the object oriented source code and extracts the strong and weak relationships between them, enabling analyzers and programmers to determine the dependency rate of each object, component, and other section of the code for parameter passing and modular programming. The proposed model can detect design patterns better that available other tools those are Pinot, PTIDEJ and DPJF; and the strengths of their relationships. Results The result demonstrate that whenever the source code is build standard and non-standard, based on the design patterns, then the result of the proposed method is near to DPJF and better that Pinot and PTIDEJ. The proposed model is tested on the several source codes and is compared with other related models and available tools those the results show the precision and recall of the proposed method, averagely 20% and 9.6% are more than Pinot, 27% and 31% are more than PTIDEJ and 3.3% and 2% are more than DPJF respectively. Conclusion The primary idea of the proposed method is organized in two following steps: the first step, elemental design patterns are identified, while at the second step, is composed to recognize actual design patterns. PMID:25243670

  18. Design pattern mining using distributed learning automata and DNA sequence alignment.

    Science.gov (United States)

    Esmaeilpour, Mansour; Naderifar, Vahideh; Shukur, Zarina

    2014-01-01

    Over the last decade, design patterns have been used extensively to generate reusable solutions to frequently encountered problems in software engineering and object oriented programming. A design pattern is a repeatable software design solution that provides a template for solving various instances of a general problem. This paper describes a new method for pattern mining, isolating design patterns and relationship between them; and a related tool, DLA-DNA for all implemented pattern and all projects used for evaluation. DLA-DNA achieves acceptable precision and recall instead of other evaluated tools based on distributed learning automata (DLA) and deoxyribonucleic acid (DNA) sequences alignment. The proposed method mines structural design patterns in the object oriented source code and extracts the strong and weak relationships between them, enabling analyzers and programmers to determine the dependency rate of each object, component, and other section of the code for parameter passing and modular programming. The proposed model can detect design patterns better that available other tools those are Pinot, PTIDEJ and DPJF; and the strengths of their relationships. The result demonstrate that whenever the source code is build standard and non-standard, based on the design patterns, then the result of the proposed method is near to DPJF and better that Pinot and PTIDEJ. The proposed model is tested on the several source codes and is compared with other related models and available tools those the results show the precision and recall of the proposed method, averagely 20% and 9.6% are more than Pinot, 27% and 31% are more than PTIDEJ and 3.3% and 2% are more than DPJF respectively. The primary idea of the proposed method is organized in two following steps: the first step, elemental design patterns are identified, while at the second step, is composed to recognize actual design patterns.

  19. Distribution patterns of fish assemblages in an Eastern Mediterranean intermittent river

    Directory of Open Access Journals (Sweden)

    Vardakas L.

    2015-01-01

    Full Text Available The distribution patterns of fish assemblages within streams can provide insights for river type classifications and may warrant specific conservation actions. However, there is limited knowledge of how fish assemblages assort along a longitudinal axis in Mediterranean intermittent streams. Patterns in spatial and temporal distribution of fish communities were analysed in a Mediterranean intermittent river (Evrotas River located in Southern Greece, hosting three endemic range restricted species of high conservation concern, during the period 2007−2009, with 80% of the river’s total length desiccating in the 2007 and 2008 droughts. The general trend was an increase in fish density and species richness along an upstream-downstream gradient. Fish assemblages from upstream to downstream were characterized by a decrease of the most rheophilic species (Squalius keadicus and an increase of the most stagnophilic species (Tropidophoxinellus spartiaticus. Three river segments, characterized by a high degree of homogeneity were delineated. Habitat and environmental preferences for the studied fish species were identified, with elevation and low flowing habitats being the most important environmental factors affecting fish distribution patterns. The current study provides evidence that even in an intermittent river an assemblage pattern following a longitudinal gradient can be identified, mainly due to the lack of instream barriers that allows recolonization after flow resumption.

  20. Protein Adsorption Patterns and Analysis on IV Nanoemulsions—The Key Factor Determining the Organ Distribution

    Directory of Open Access Journals (Sweden)

    Mirko Jansch

    2012-12-01

    Full Text Available Intravenous nanoemulsions have been on the market for parenteral nutrition since the 1950s; meanwhile, they have also been used successfully for IV drug delivery. To be well tolerable, the emulsions should avoid uptake by the MPS cells of the body; for drug delivery, they should be target-specific. The organ distribution is determined by the proteins adsorbing them after injection from the blood (protein adsorption pattern, typically analyzed by two-dimensional polyacrylamide gel electrophoresis, 2-D PAGE. The article reviews the 2-D PAGE method, the analytical problems to be faced and the knowledge available on how the composition of emulsions affects the protein adsorption patterns, e.g., the composition of the oil phase, stabilizer layer and drug incorporation into the interface or oil core. Data were re-evaluated and compared, and the implications for the in vivo distribution are discussed. Major results are that the interfacial composition of the stabilizer layer is the main determining factor and that this composition can be modulated by simple processes. Drug incorporation affects the pattern depending on the localization of the drug (oil core versus interface. The data situation regarding in vivo effects is very limited; mainly, it has to be referred to in the in vivo data of polymeric nanoparticles. As a conclusion, determination of the protein adsorption patterns can accelerate IV nanoemulsion formulation development regarding optimized organ distribution and related pharmacokinetics.

  1. MartiTracks: a geometrical approach for identifying geographical patterns of distribution.

    Directory of Open Access Journals (Sweden)

    Susy Echeverría-Londoño

    Full Text Available Panbiogeography represents an evolutionary approach to biogeography, using rational cost-efficient methods to reduce initial complexity to locality data, and depict general distribution patterns. However, few quantitative, and automated panbiogeographic methods exist. In this study, we propose a new algorithm, within a quantitative, geometrical framework, to perform panbiogeographical analyses as an alternative to more traditional methods. The algorithm first calculates a minimum spanning tree, an individual track for each species in a panbiogeographic context. Then the spatial congruence among segments of the minimum spanning trees is calculated using five congruence parameters, producing a general distribution pattern. In addition, the algorithm removes the ambiguity, and subjectivity often present in a manual panbiogeographic analysis. Results from two empirical examples using 61 species of the genus Bomarea (2340 records, and 1031 genera of both plants and animals (100118 records distributed across the Northern Andes, demonstrated that a geometrical approach to panbiogeography is a feasible quantitative method to determine general distribution patterns for taxa, reducing complexity, and the time needed for managing large data sets.

  2. Comparing Two Types of Fertilizer Distributor (centrifuge in Order to ptimize the Pattern of Fertilizer Distribution

    Directory of Open Access Journals (Sweden)

    P Ahmadi Moghaddam

    2013-09-01

    Full Text Available Increasing demand for food production in the recent years has raised the usage of granular fertilizers. Consequently, the growing use of fertilizers has reduced the quality and quantity of crop production. In addition pollution problems such as soil and water (surface and subterranean water contaminations has increased. Consistent spreading of fertilizers in the farmlands is of fundamental rules in conventional framings. In present study, the effects of the number and the arrangement (position of blades of a single disk fertilizer distributer and for two different fertilizers were investigated in order to obtain optimized distribution of fertilizer. The tests were conducted in factorial arrangement and in a completely randomized model. The variables were the number of blades in three levels of 4, 6 and 8, the blade position angles (in two patterns of radial and non-radial and the type of fertilizer (phosphate and nitrate. Statistical analysis of results indicated that the number of blades on the disk and type of fertilizer are not effective parameters in order to reach a consistent distribution pattern of fertilizer while the position of blades on the disk has significant influence for this purpose. The best pattern of distribution was obtained from the disk with four non-radial blades and nitrate fertilizer.

  3. Distributional patterns of herbivore megamammals during the Late Pleistocene of South America

    Directory of Open Access Journals (Sweden)

    VALERIA GALLO

    2013-06-01

    Full Text Available The geographic distribution of 27 species of the South American megafauna of herbivore mammals during the Late Pleistocene was analyzed in order to identify their distributional patterns. The distribution of the species was studied using the panbiogeographical method of track analysis. Six generalized tracks (GTs and two biogeographic nodes were obtained. The GTs did not completely superpose with the areas of open savanna present in Pleistocene, nor with the biotic tracks of some arthropods typical of arid climate, indicating that these animals avoided arid environment. Overall, the GTs coincided with some biogeographic provinces defined on the basis of living taxa, indicating that certain current distributional patterns already existed in Pleistocene. The biogeographic nodes coincided with the borders between the main vegetal formations of the Pleistocene, showing that the type of vegetation had great influence in the distribution of the mammalian megafauna. The node 1 confirmed the existence of contact zones between paleobiogeographic regions near Argentina-Uruguay border. The node 2 connects the Brazilian Intertropical regions.

  4. Distributed Storage Algorithm for Geospatial Image Data Based on Data Access Patterns.

    Directory of Open Access Journals (Sweden)

    Shaoming Pan

    Full Text Available Declustering techniques are widely used in distributed environments to reduce query response time through parallel I/O by splitting large files into several small blocks and then distributing those blocks among multiple storage nodes. Unfortunately, however, many small geospatial image data files cannot be further split for distributed storage. In this paper, we propose a complete theoretical system for the distributed storage of small geospatial image data files based on mining the access patterns of geospatial image data using their historical access log information. First, an algorithm is developed to construct an access correlation matrix based on the analysis of the log information, which reveals the patterns of access to the geospatial image data. Then, a practical heuristic algorithm is developed to determine a reasonable solution based on the access correlation matrix. Finally, a number of comparative experiments are presented, demonstrating that our algorithm displays a higher total parallel access probability than those of other algorithms by approximately 10-15% and that the performance can be further improved by more than 20% by simultaneously applying a copy storage strategy. These experiments show that the algorithm can be applied in distributed environments to help realize parallel I/O and thereby improve system performance.

  5. Size matters: point pattern analysis biases the estimation of spatial properties of stomata distribution.

    Science.gov (United States)

    Naulin, Paulette I; Valenzuela, Gerardo; Estay, Sergio A

    2017-03-01

    Stomata distribution is an example of biological patterning. Formal methods used to study stomata patterning are generally based on point-pattern analysis, which assumes that stomata are points and ignores the constraints imposed by size on the placement of neighbors. The inclusion of size in the analysis requires the use of a null model based on finite-size object geometry. In this study, we compare the results obtained by analyzing samples from several species using point and disc null models. The results show that depending on the null model used, there was a 20% reduction in the number of samples classified as uniform; these results suggest that stomata patterning is not as general as currently reported. Some samples changed drastically from being classified as uniform to being classified as clustered. In samples of Arabidopsis thaliana, only the disc model identified clustering at high densities of stomata. This reinforces the importance of selecting an appropriate null model to avoid incorrect inferences about underlying biological mechanisms. Based on the results gathered here, we encourage researchers to abandon point-pattern analysis when studying stomata patterning; more realistic conclusions can be drawn from finite-size object analysis. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  6. Mammographic Breast Density in Chinese Women: Spatial Distribution and Autocorrelation Patterns.

    Science.gov (United States)

    Lai, Christopher W K; Law, Helen K W

    2015-01-01

    Mammographic breast density (MBD) is a strong risk factor for breast cancer. The spatial distribution of MBD in the breast is variable and dependent on physiological, genetic, environmental and pathological factors. This pilot study aims to define the spatial distribution and autocorrelation patterns of MBD in Chinese women aged 40-60. By analyzing their digital mammographic images using a public domain Java image processing program for segmentation and quantification of MBD, we found their left and right breasts were symmetric to each other in regard to their breast size (Total Breast Area), the amount of BMD (overall PD) and Moran's I values. Their MBD was also spatially autocorrelated together in the anterior part of the breast in those with a smaller breast size, while those with a larger breast size tend to have their MBD clustered near the posterior part of the breast. Finally, we observed that the autocorrelation pattern of MBD was dispersed after a 3-year observation period.

  7. Historical distribution patterns of trigonioidids (non-marine Cretaceous bivalves) in Asia and their palaeogeographic significance

    Science.gov (United States)

    Sha, Jingeng

    2010-01-01

    The non-marine trigonioidid bivalves show five phases of radiation in the Cretaceous of Pal-Asia: pre-Aptian (?Valanginian/Hauterivian–Barremian), Aptian, Albian, Cenomanian and Turonian–Maastrichtian. Their distribution patterns show two distinct palaeo-river systems feeding trigonioidids. Before the Cenomanian, the river system occupied the southwestern–southern–southeastern Pal-Asian continental margin areas. During the Turonian–Maastrichtian, it extended along the line of southcentral China−eastern China−northeastern China−northern China and Mongolia−northwestern China–eastern Fergana Basin of Kyrgyzstan−western Tajikistan Basin of Tajikistan–Tashkent area of Kazakhstan−central Kyzylkum of northern Uzbekistan–Aral Sea area of Kazakhstan. Furthermore, the general trigonioidid distribution pattern demonstrates that Japan was probably attached to part of eastern China and/or Korea during the ?Valanginian/Hauterivian–Cenomanian stages. PMID:19605391

  8. Synthesis of Seafood Catch, Distribution, and Consumption Patterns in the Gulf of Mexico Region

    Energy Technology Data Exchange (ETDEWEB)

    Steimle and Associates, Inc.

    1999-08-16

    The purpose of this task was to gather and assemble information that will provide a synthesis of seafood catch, distribution and consumption patterns for the Gulf of Mexico (GOM) region. This task was part of a U.S. Department of Energy (DOE)-sponsored project entitled ''Environmental and Economic Assessment of Discharges from Gulf of Mexico Region Oil and Gas Operations.'' Personal interviews were conducted with a total of 905 recreational fishermen and 218 commercial fishermen (inclusive of shrimpers, crabbers, oystermen and finfishermen) in Louisiana and Texas using survey questionnaires developed for the study. Results of these interviews detail the species and quantities caught, location of catch, mode of fishing, distribution of catch, family consumption patterns and demographics of the fishermen.

  9. Public policy and population distribution: developing appropriate indicators of settlement patterns

    OpenAIRE

    Mike Coombes; Simon Raybould

    2001-01-01

    In this paper we are concerned with the measurement of aspects of population distribution, or settlement patterns, and the use of these measures in public-policy contexts in particular. More specifically, we query the adequacy of the population-density indicator, which is widely used in statistical formulae such as those by which the British government allocates funding to English local authorities. Our approach is to work through a series of topics, starting with an introductory discussion o...

  10. Hypothesizing Origin, Migration Routes and Distribution Patterns of Gymnosperms in Taiwan

    Directory of Open Access Journals (Sweden)

    Shing-Fan Huang

    2014-06-01

    Full Text Available Phytogeographical study of gymnosperms in Taiwan is carried out based on reviewing data gathered from published papers on fossils, phylogeny and phylogeography. Following questions are asked. (1 How is the high degree of endemism of gymnosperm flora of Taiwan derived? (2 How many source areas of gymnosperms in Taiwan are there? (3 Is there relation between distribution pattern of endemic gymnosperms in Taiwan and those of their sister species? (4 How do gymnosperms migrate to Taiwan?

  11. Quantifying shark distribution patterns and species-habitat associations: implications of marine park zoning.

    Science.gov (United States)

    Espinoza, Mario; Cappo, Mike; Heupel, Michelle R; Tobin, Andrew J; Simpfendorfer, Colin A

    2014-01-01

    Quantifying shark distribution patterns and species-specific habitat associations in response to geographic and environmental drivers is critical to assessing risk of exposure to fishing, habitat degradation, and the effects of climate change. The present study examined shark distribution patterns, species-habitat associations, and marine reserve use with baited remote underwater video stations (BRUVS) along the entire Great Barrier Reef Marine Park (GBRMP) over a ten year period. Overall, 21 species of sharks from five families and two orders were recorded. Grey reef Carcharhinus amblyrhynchos, silvertip C. albimarginatus, tiger Galeocerdo cuvier, and sliteye Loxodon macrorhinus sharks were the most abundant species (>64% of shark abundances). Multivariate regression trees showed that hard coral cover produced the primary split separating shark assemblages. Four indicator species had consistently higher abundances and contributed to explaining most of the differences in shark assemblages: C. amblyrhynchos, C. albimarginatus, G. cuvier, and whitetip reef Triaenodon obesus sharks. Relative distance along the GBRMP had the greatest influence on shark occurrence and species richness, which increased at both ends of the sampling range (southern and northern sites) relative to intermediate latitudes. Hard coral cover and distance across the shelf were also important predictors of shark distribution. The relative abundance of sharks was significantly higher in non-fished sites, highlighting the conservation value and benefits of the GBRMP zoning. However, our results also showed that hard coral cover had a large effect on the abundance of reef-associated shark species, indicating that coral reef health may be important for the success of marine protected areas. Therefore, understanding shark distribution patterns, species-habitat associations, and the drivers responsible for those patterns is essential for developing sound management and conservation approaches.

  12. Quantifying shark distribution patterns and species-habitat associations: implications of marine park zoning.

    Directory of Open Access Journals (Sweden)

    Mario Espinoza

    Full Text Available Quantifying shark distribution patterns and species-specific habitat associations in response to geographic and environmental drivers is critical to assessing risk of exposure to fishing, habitat degradation, and the effects of climate change. The present study examined shark distribution patterns, species-habitat associations, and marine reserve use with baited remote underwater video stations (BRUVS along the entire Great Barrier Reef Marine Park (GBRMP over a ten year period. Overall, 21 species of sharks from five families and two orders were recorded. Grey reef Carcharhinus amblyrhynchos, silvertip C. albimarginatus, tiger Galeocerdo cuvier, and sliteye Loxodon macrorhinus sharks were the most abundant species (>64% of shark abundances. Multivariate regression trees showed that hard coral cover produced the primary split separating shark assemblages. Four indicator species had consistently higher abundances and contributed to explaining most of the differences in shark assemblages: C. amblyrhynchos, C. albimarginatus, G. cuvier, and whitetip reef Triaenodon obesus sharks. Relative distance along the GBRMP had the greatest influence on shark occurrence and species richness, which increased at both ends of the sampling range (southern and northern sites relative to intermediate latitudes. Hard coral cover and distance across the shelf were also important predictors of shark distribution. The relative abundance of sharks was significantly higher in non-fished sites, highlighting the conservation value and benefits of the GBRMP zoning. However, our results also showed that hard coral cover had a large effect on the abundance of reef-associated shark species, indicating that coral reef health may be important for the success of marine protected areas. Therefore, understanding shark distribution patterns, species-habitat associations, and the drivers responsible for those patterns is essential for developing sound management and conservation

  13. Distribution patterns of influenza virus receptors and viral attachment patterns in the respiratory and intestinal tracts of seven avian species

    Directory of Open Access Journals (Sweden)

    Costa Taiana

    2012-04-01

    Full Text Available Abstract This study assessed the presence of sialic acid α-2,3 and α-2,6 linked glycan receptors in seven avian species. The respiratory and intestinal tracts of the chicken, common quail, red-legged partridge, turkey, golden pheasant, ostrich, and mallard were tested by means of lectin histochemistry, using the lectins Maackia amurensis agglutinin II and Sambucus nigra agglutinin, which show affinity for α-2,3 and α-2,6 receptors, respectively. Additionally, the pattern of virus attachment (PVA was evaluated with virus histochemistry, using an avian-origin H4N5 virus and a human-origin seasonal H1N1 virus. There was a great variation of receptor distribution among the tissues and avian species studied. Both α-2,3 and α-2,6 receptors were present in the respiratory and intestinal tracts of the chicken, common quail, red-legged partridge, turkey, and golden pheasant. In ostriches, the expression of the receptor was basically restricted to α-2,3 in both the respiratory and intestinal tracts and in mallards the α-2,6 receptors were absent from the intestinal tract. The results obtained with the lectin histochemistry were, in general, in agreement with the PVA. The differential expression and distribution of α-2,3 and α-2,6 receptors among various avian species might reflect a potentially decisive factor in the emergence of new viral strains.

  14. Effects of habitat fragmentation and road density on the distribution pattern of the moor frog Rana arvalis.

    NARCIS (Netherlands)

    Vos, C.C.; Chardon, P.

    1998-01-01

    1. The effects of habitat fragmentation on the distribution pattern of the moor frog Rana arvalis were investigated. Also, the possible isolation effects of the road network were taken into account. 2. Indications were found that habitat fragmentation partly explains the distribution pattern of the

  15. Foraging pattern, colony distribution, and foraging range of the Florida harvester ant, Pogonomyrmex badius

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, J.S. (Savannah River Ecology Laboratory); Gentry, J.B.; Aiken, S.C.

    1981-12-01

    This report describes the foraging pattern of the Florida harvester ant Pogonomyrmex badius in a high-density population of colonies. The foraging pattern has both promoted and been influenced by the colony distribution. Pogonomyrmex badius forages from short trails which extend into a surrounding foraging range. Direction of foraging trails is influenced by the location of a colony's near neighbors. Seasonal nest relocations always occur along a foraging trail, usually the main trail. Foraging ranges are not actively defended, but are used almost exclusively by foragers from a single colony. Foraging ranges will be extended into an area abandoned by neighboring foragers, indicating that forager presence may define each colony's range. Colony distribution has remained essentially the same for several years, despite seasonal nest relocations and addition of new colonies. Establishment of trails and exclusive foraging ranges by each colony minimizes encounters with neighboring foragers and guarantees access to available resources; this pattern also promotes maintenance of the existing colony distribution and partitioning of resources.

  16. Foraging pattern, colony distribution, and foraging range of the Florida harvester ant Pogonomyrmex badius

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, J.S.; Gentry, J.B.

    1981-12-01

    This report describes the foraging pattern of the Florida harvester ant Pogonomyrmex badius in a high-density population of colonies. The foraging pattern has both promoted and been influenced by the colony distribution. Pogonomyrmex badius forages from short trails which extend into a surrounding foraging range. Direction of foraging trails is influenced by the location of a colony's near neighbors. Seasonal nest relocations always occur along a foraging trail, usually the main trail. Foraging ranges are not actively defended, but are used almost exclusively by foragers from a single colony. Foraging ranges will be extended into an area abondoned by neighboring foragers, indicating that forager presence may define each colony's range. Colony distribution has remained essentially the same for several years, despite seasonal nest relocations and addition of new colonies. Establishment of trails and exclusive foraging ranges by each colony minimizes encounters with neighboring foragers and guarantees access to available resources; this pattern also pomotes maintenance of the existing colony distribution and partitioning of resources.

  17. Patterns of distribution of the helminth parasites of freshwater fishes of Mexico.

    Science.gov (United States)

    Quiroz-Martínez, Benjamín; Salgado-Maldonado, Guillermo

    2013-01-01

    In order to draw patterns in helminth parasite composition and species richness in Mexican freshwater fishes we analyse a presence-absence matrix representing every species of adult helminth parasites of freshwater fishes from 23 Mexican hydrological basins. We examine the distributional patterns of the helminth parasites with regard to the main hydrological basins of the country, and in doing so we identify areas of high diversity and point out the biotic similarities and differences among drainage basins. Our dataset allows us to evaluate the relationships among drainage basins in terms of helminth diversity. This paper shows that the helminth fauna of freshwater fishes of Mexico can characterise hydrological basins the same way as fish families do, and that the basins of south-eastern Mexico are home to a rich, predominantly Neotropical, helminth fauna whereas the basins of the Mexican Highland Plateau and the Nearctic area of Mexico harbour a less diverse Nearctic fauna, following the same pattern of distribution of their fish host families. The composition of the helminth fauna of each particular basin depends on the structure of the fish community rather than on the limnological characteristics and geographical position of the basin itself. This work shows distance decay of similarity and a clear linkage between host and parasite distributions.

  18. Patterns, biases and prospects in the distribution and diversity of Neotropical snakes.

    Science.gov (United States)

    Guedes, Thaís B; Sawaya, Ricardo J; Zizka, Alexander; Laffan, Shawn; Faurby, Søren; Pyron, R Alexander; Bérnils, Renato S; Jansen, Martin; Passos, Paulo; Prudente, Ana L C; Cisneros-Heredia, Diego F; Braz, Henrique B; Nogueira, Cristiano de C; Antonelli, Alexandre; Meiri, Shai

    2018-01-01

    We generated a novel database of Neotropical snakes (one of the world's richest herpetofauna) combining the most comprehensive, manually compiled distribution dataset with publicly available data. We assess, for the first time, the diversity patterns for all Neotropical snakes as well as sampling density and sampling biases. We compiled three databases of species occurrences: a dataset downloaded from the Global Biodiversity Information Facility (GBIF), a verified dataset built through taxonomic work and specialized literature, and a combined dataset comprising a cleaned version of the GBIF dataset merged with the verified dataset. Neotropics, Behrmann projection equivalent to 1° × 1°. Specimens housed in museums during the last 150 years. Squamata: Serpentes. Geographical information system (GIS). The combined dataset provides the most comprehensive distribution database for Neotropical snakes to date. It contains 147,515 records for 886 species across 12 families, representing 74% of all species of snakes, spanning 27 countries in the Americas. Species richness and phylogenetic diversity show overall similar patterns. Amazonia is the least sampled Neotropical region, whereas most well-sampled sites are located near large universities and scientific collections. We provide a list and updated maps of geographical distribution of all snake species surveyed. The biodiversity metrics of Neotropical snakes reflect patterns previously documented for other vertebrates, suggesting that similar factors may determine the diversity of both ectothermic and endothermic animals. We suggest conservation strategies for high-diversity areas and sampling efforts be directed towards Amazonia and poorly known species.

  19. Spatial Distribution Patterns in the Very Rare and Species-Rich Picea chihuahuana Tree Community (Mexico)

    Science.gov (United States)

    Wehenkel, Christian; Brazão-Protázio, João Marcelo; Carrillo-Parra, Artemio; Martínez-Guerrero, José Hugo; Crecente-Campo, Felipe

    2015-01-01

    The very rare Mexican Picea chihuahuana tree community covers an area of no more than 300 ha in the Sierra Madre Occidental. This special tree community has been the subject of several studies aimed at learning more about the genetic structure and ecology of the species and the potential effects of climate change. The spatial distribution of trees is a result of many ecological processes and can affect the degree of competition between neighbouring trees, tree density, variability in size and distribution, regeneration, survival, growth, mortality, crown formation and the biological diversity within forest communities. Numerous scale-dependent measures have been established in order to describe spatial forest structure. The overall aim of most of these studies has been to obtain data to help design preservation and conservation strategies. In this study, we examined the spatial distribution pattern of trees in the P. chihuahuana tree community in 12 localities, in relation to i) tree stand density, ii) diameter distribution (vertical structure), iii) tree species diversity, iv) geographical latitude and v) tree dominance at a fine scale (in 0.25 ha plots), with the aim of obtaining a better understanding of the complex ecosystem processes and biological diversity. Because of the strongly mixed nature of this tree community, which often produces low population densities of each tree species and random tree fall gaps caused by tree death, we expect aggregated patterns in individual Picea chihuahuana trees and in the P. chihuahuana tree community, repulsive Picea patterns to other tree species and repulsive patterns of young to adult trees. Each location was represented by one plot of 50 x 50 m (0.25 ha) established in the centre of the tree community. The findings demonstrate that the hypothesis of aggregated tree pattern is not applicable to the mean pattern measured by Clark-Evans index, Uniform Angle index and Mean Directional index of the uneven-aged P

  20. Spatial Distribution Patterns in the Very Rare and Species-Rich Picea chihuahuana Tree Community (Mexico.

    Directory of Open Access Journals (Sweden)

    Christian Wehenkel

    Full Text Available The very rare Mexican Picea chihuahuana tree community covers an area of no more than 300 ha in the Sierra Madre Occidental. This special tree community has been the subject of several studies aimed at learning more about the genetic structure and ecology of the species and the potential effects of climate change. The spatial distribution of trees is a result of many ecological processes and can affect the degree of competition between neighbouring trees, tree density, variability in size and distribution, regeneration, survival, growth, mortality, crown formation and the biological diversity within forest communities. Numerous scale-dependent measures have been established in order to describe spatial forest structure. The overall aim of most of these studies has been to obtain data to help design preservation and conservation strategies. In this study, we examined the spatial distribution pattern of trees in the P. chihuahuana tree community in 12 localities, in relation to i tree stand density, ii diameter distribution (vertical structure, iii tree species diversity, iv geographical latitude and v tree dominance at a fine scale (in 0.25 ha plots, with the aim of obtaining a better understanding of the complex ecosystem processes and biological diversity. Because of the strongly mixed nature of this tree community, which often produces low population densities of each tree species and random tree fall gaps caused by tree death, we expect aggregated patterns in individual Picea chihuahuana trees and in the P. chihuahuana tree community, repulsive Picea patterns to other tree species and repulsive patterns of young to adult trees. Each location was represented by one plot of 50 x 50 m (0.25 ha established in the centre of the tree community. The findings demonstrate that the hypothesis of aggregated tree pattern is not applicable to the mean pattern measured by Clark-Evans index, Uniform Angle index and Mean Directional index of the uneven

  1. Heavy oil, water and air three-phase flow patterns in horizontal pipes; Padroes de escoamento trifasico de oleo pesado, agua e ar em tubulacoes horizontais

    Energy Technology Data Exchange (ETDEWEB)

    Trevisan, Francisco Exaltacao; Bannwart, Antonio Carlos [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil)

    2004-07-01

    A significant extent of the Brazilian oil reserves consists of heavy oil, and its importance and economic value have been increasing in the last years. However, these oils, besides their elevated densities (API degree lower than 20), have viscosities higher than 100 mPa.s, which make it more difficult their transportation in pipelines. A solution for this problem is the injection of water in the pipe, which causes a reduction of the friction factor and, consequently, of the energy expend for a given oil flow rate. The two-phase flow of heavy oil and water has been the object of a number of recent studies, and concepts such as the core-flow technology can be useful for heavy oil transportation. But in production operations, gas is also present, initially dissolved in the oil phase then leaving the solution to form a free gas phase if the pressure drops below the bubble point pressure, the study of three-phase flow of heavy oil, water and gas is in order. The present paper presents the experimental work developed to evaluate the effect that this third phase causes on the heavy oil-water two-phase flow pattern. Initially two-phase flow of heavy and gas-water was studied to establish the flow rate ranges that cover the main patterns already known. The superficial velocities used varied from 0,04 to 0,5 m/s for water, 0,01 to 22 m/s for gas and 0,02 to 1,2 m/s for oil. After that, three-phase flow patterns were visually determined through a 2,84 cm i.d. plexiglas tube using a high-speed camera. Nine three-phase flow patterns were identified which are presented visually and described. These flow-patterns are also presented in flow maps where the effect of the gas phase can be observed. Water was the continuous phase for all flow patterns observed, ensuring a low pressure drop along the pipe. (author)

  2. Global distribution of a key trophic guild contrasts with common latitudinal diversity patterns.

    Science.gov (United States)

    Boyero, Luz; Pearson, Richard G; Dudgeon, David; Graça, Manuel A S; Gessner, Mark O; Albariño, Ricardo J; Ferreira, Verónica; Yule, Catherine M; Boulton, Andrew J; Arunachalam, Muthukumarasamy; Callisto, Marcos; Chauvet, Eric; Ramírez, Alonso; Chará, Julián; Moretti, Marcelo S; Gonçalves, José F; Helson, Julie E; Chará-Serna, Ana M; Encalada, Andrea C; Davies, Judy N; Lamothe, Sylvain; Cornejo, Aydeè; Li, Aggie O Y; Buria, Leonardo M; Villanueva, Verónica D; Zúñiga, María C; Pringle, Catherine M

    2011-09-01

    Most hypotheses explaining the general gradient of higher diversity toward the equator are implicit or explicit about greater species packing in the tropics. However, global patterns of diversity within guilds, including trophic guilds (i.e., groups of organisms that use similar food resources), are poorly known. We explored global diversity patterns of a key trophic guild in stream ecosystems, the detritivore shredders. This was motivated by the fundamental ecological role of shredders as decomposers of leaf litter and by some records pointing to low shredder diversity and abundance in the tropics, which contrasts with diversity patterns of most major taxa for which broad-scale latitudinal patterns haven been examined. Given this evidence, we hypothesized that shredders are more abundant and diverse in temperate than in tropical streams, and that this pattern is related to the higher temperatures and lower availability of high-quality leaf litter in the tropics. Our comprehensive global survey (129 stream sites from 14 regions on six continents) corroborated the expected latitudinal pattern and showed that shredder distribution (abundance, diversity and assemblage composition) was explained by a combination of factors, including water temperature (some taxa were restricted to cool waters) and biogeography (some taxa were more diverse in particular biogeographic realms). In contrast to our hypothesis, shredder diversity was unrelated to leaf toughness, but it was inversely related to litter diversity. Our findings markedly contrast with global trends of diversity for most taxa, and with the general rule of higher consumer diversity at higher levels of resource diversity. Moreover, they highlight the emerging role of temperature in understanding global patterns of diversity, which is of great relevance in the face of projected global warming.

  3. Effects of Mie tip-vane on pressure distribution of rotor blade and power augmentation of horizontal axis wind turbine; Yokutan shoyoku Mie ben ni yoru suiheijiku fusha yokumenjo no atsuryoku bunpu no kaizen to seino kojo tono kankei

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Y.; Maeda, T.; Kamada, Y. [Mie Univ., Mie (Japan); Seto, H. [Mitsubishi Motors Corp., Tokyo (Japan)

    2000-04-01

    By recent developments of exclusive rotor blade, the efficiency of wind turbine is improved substantially. By measuring pressure on rotor blades of horizontal axis wind turbines rotating in wind tunnels, this report clarified relation between improvement of pressure distribution on main rotor blades by Mie vane and upgrade of wind turbine performance. The results under mentioned have been got by measuring pressure distribution on rotor blades, visualization by tuft, and measuring resistance of Mie vane. (1) The difference of pressure between suction surface and pressure surface on the end of rotor blade increase, and output power of wind turbine improves. (2) Vortex of blade end is inhibited by Mie vane. (3) The reason of reduction on wind turbine performance with Mie vane in aria of high rotating speed ratio is the increase of Mie vane flow resistance.(NEDO)

  4. Carbon dioxide and R410A flow boiling heat transfer, pressure drop, and flow pattern in horizontal tubes at low temperatures

    Science.gov (United States)

    Park, Chang Yong

    Carbon dioxide (CO2) has been seriously considered as an alternate refrigerant for HCFC and HFC fluids, due to the increasing interest of environmentally safe refrigerants in air-conditioning and refrigeration systems. In this study, CO2 flow boiling heat transfer coefficients and pressure drop are measured in macro-scale (6.1 and 3.5 mm) tubes at evaporation temperatures of -15 and -30°C. The measured results show that the nucleate boiling is a main heat transfer mechanism in the 6.1 mm tube and the contribution of convective boiling becomes greater with the decrease of tube diameters and the increase of mass fluxes. The surface roughness of the 6.1 and 3.5 mm tube are presented by SEM and AFM images and surface profiles, and it is shown that the rougher surface of the 6.1 mm tube can affect the flow boiling heat transfer. The CO2 heat transfer coefficients and pressure drop are measured in a mini-scale (0.89 mm) multi-ported tube at the evaporation temperature of -30°C. Also, R410A and R22 flow boiling heat transfer coefficients and pressure drop in a macro-scale (6.1 mm) tube were measured, and they are compared with CO2. This comparison presents that the CO2 flow boiling heat transfer coefficients are higher than R410A and R22 at low vapor qualities, and CO2 pressure drop is significantly lower than R410A and R22. This advantageous characteristic for CO2 could be explained by properties such as surface tension, reduced pressure, and the density ratio of liquid to vapor. The prediction of heat transfer coefficients and pressure drop was performed by general correlations and the calculation results are compared with measured values. Two-phase flow patterns were visualized for CO2 and R410A in the 6 and 3 mm glass tubes, and they are compared with the Weisman et al. and the Wojtan et al. flow pattern maps. The flow pattern maps can determine the flow patterns relatively well, except the transition from intermittent to annular flow.

  5. [Spatial distribution of human activities and their influences on landscape patterns in Daqingshan Nature Reserve].

    Science.gov (United States)

    Sun, Ya-Hui; Meng, Li; Tian, Lü; Li, Guo-Liang; Li, Yue-Hui; Sun, Jian-Xin

    2014-11-01

    Based on forest inventory data and field survey information, and by using GIS spatial analysis technique and landscape indices, this paper studied the spatial distribution of three categories of human activities (settlement, roads, and other sources of disturbances) and their impacts on landscape patterns in three sub-divided regions, i. e., the west, central and east regions of the Daqingshan Nature Reserve in Inner Mongolia. Results showed that the impacts of human activities were stronger in the east and west regions and weaker in the central region. Among the three subdivided regions, the landscape pattern in the west region was predominantly affected by other sources of disturbances, making the landscape patterns of coniferous forests, broadleaf forests and shrubs tended to be of aggregated distribution; the central region was mainly affected by roads, resulting in reduced landscape patch aggregation of broadleaf forests and shrubs; the east region was mostly affected by settlement, resulting in increased fragmentation of coniferous forests and broadleaf forests and apparent increases in landscape patch aggregation of shrubs and grasslands.

  6. Population ecology of Paepalanthus polyanthus (Bong. Kunth: temporal variation in the pattern of spatial distribution

    Directory of Open Access Journals (Sweden)

    Tânia Tarabini Castellani

    2004-11-01

    Full Text Available The temporal variation in density and pattern of spatial distribution of Paepalanthus polyanthus (BONG. Kunth (Eriocaulaceae were evaluated at a determinate sand dune. This study was carried out over a period of five years, at three permanent plots of 25m2 in a sand dune slack at Joaquina Beach, Florianópolis, SC, Brazil. There were strong density fluctuations throughout these years. In areas 1, 2 and 3, the densities changed from 10.4, 2.2 and 1.8 plants/m2 in December 1986 to 75.8, 11.4 and 45.6 plants/m2 in December 1991. Area 3, situated on an elevated site, presented greater variation in density, with no live plants in December 1989 and 102.2 plants/m2 at the recruitment observed in May 1990. Despite these density fluctuations, the pattern of spatial distribution was always aggregated (Id>1, P<0.05. The greatest Id values occurred in periods of low density and not in those of high density, associated with seedling recruitment. Factors such as high seed production with low dispersal, massive germination in moit years and a comparatively high death rate of seedlings at sites more subject to flooding or more distant from the water table proved themselves able to promote this aggregate pattern and increase it during plant development.

  7. High-resolution pattern of mangrove species distribution is controlled by surface elevation

    Science.gov (United States)

    Leong, Rick C.; Friess, Daniel A.; Crase, Beth; Lee, Wei Kit; Webb, Edward L.

    2018-03-01

    Mangrove vegetation species respond to multiple environmental gradients, and an enhanced understanding of how mangrove species are distributed across these gradients will facilitate conservation and management. Many environmental gradients correlate with tidal inundation; however small-scale inundation patterns resulting from microtopographical changes are difficult to capture empirically. In contrast, surface elevation is often a suitable, measurable and cost-effective proxy for inundation. This study investigated the relationships between species distribution and surface elevation in a mangrove forest in northwest Singapore. Through high-resolution land surveying, we developed a digital elevation model (DEM) and conducted a comprehensive survey of 4380 trees with a stem diameter ≥ 5 cm. A total of 15 species were encountered, and elevation envelopes were generated for 12. Species envelopes were distributed along an elevation continuum, with most species overlapping within the continuum. Spatial autocorrelation (SAC) was present for nine of the 15 species, and when taken into account, species ordering was modified across the elevation continuum. The presence of SAC strongly reinforces the need for research to control for SAC: classical spatial description of mangrove species distribution should be revised to account for ecological factors. This study suggests that (1) surface elevation applies strong controls on species distribution and (2) most mangroves at our study site have similar physiological tolerances.

  8. Modeling thalamocortical cell: impact of ca channel distribution and cell geometry on firing pattern.

    Science.gov (United States)

    Zomorrodi, Reza; Kröger, Helmut; Timofeev, Igor

    2008-01-01

    The influence of calcium channel distribution and geometry of the thalamocortical cell upon its tonic firing and the low threshold spike (LTS) generation was studied in a 3-compartment model, which represents soma, proximal and distal dendrites as well as in multi-compartment model using the morphology of a real reconstructed neuron. Using an uniform distribution of Ca(2+) channels, we determined the minimal number of low threshold voltage-activated calcium channels and their permeability required for the onset of LTS in response to a hyperpolarizing current pulse. In the 3-compartment model, we found that the channel distribution influences the firing pattern only in the range of 3% below the threshold value of total T-channel density. In the multi-compartmental model, the LTS could be generated by only 64% of unequally distributed T-channels compared to the minimal number of equally distributed T-channels. For a given channel density and injected current, the tonic firing frequency was found to be inversely proportional to the size of the cell. However, when the Ca(2+) channel density was elevated in soma or proximal dendrites, then the amplitude of LTS response and burst spike frequencies were determined by the ratio of total to threshold number of T-channels in the cell for a specific geometry.

  9. Topographic distribution pattern of morphologically different G cells in the murine antral mucosa

    Directory of Open Access Journals (Sweden)

    Claudia Frick

    2017-09-01

    Full Text Available Gastrin-secreting enteroendocrine cells (G cells in the antrum play an important role in the regulation of gastric secretion, gastric motility and mucosal cell proliferation. Recently we have uncovered the existence of two subpopulations of G cells with pivotally different morphology and a distinct localization in the antral invaginations; the functional implications of the different G cell types are still elusive. In this study a transgenic mouse line in which EGFP is expressed under the control of a gastrin promoter was used to elucidate the distribution pattern of the two G cell types throughout the different regions of the antrum. The results of immunohistochemical analyses revealed that G cells were not equally distributed along the anterior/posterior axis of the antrum. The “typical” pyramidal- or roundish-shaped G cells, which are located in the basal region of the antral invaginations, were more abundant in the proximal antrum bordering the corpus region but less frequent in the distal antrum bordering the pylorus. In contrast, the “atypical” G cells, which are located in the upper part of the antral invaginations and have a spindle-like contour with long processes, were evenly distributed along the anterior/posterior axis. This characteristic topographic segregation supports the notion that the two G cell types may serve different functions. A comparison of the antrum specific G cells with the two pan-gastrointestinal enteroendocrine cell types, somatostatin-secreting D cells and serotonin-secreting enterochromaffin (EC cells, revealed a rather similar distribution pattern of G and D cells, but a fundamentally different distribution of EC cells. These observations suggest that distinct mechanisms govern the spatial segregation of enteroendocrine cells in the antrum mucosa.

  10. Decoding Size Distribution Patterns in Marine and Transitional Water Phytoplankton: From Community to Species Level

    Science.gov (United States)

    Roselli, Leonilde; Basset, Alberto

    2015-01-01

    Understanding the mechanisms of phytoplankton community assembly is a fundamental issue of aquatic ecology. Here, we use field data from transitional (e.g. coastal lagoons) and coastal water environments to decode patterns of phytoplankton size distribution into organization and adaptive mechanisms. Transitional waters are characterized by higher resource availability and shallower well-mixed water column than coastal marine environments. Differences in physico-chemical regime between the two environments have been hypothesized to exert contrasting selective pressures on phytoplankton cell morphology (size and shape). We tested the hypothesis focusing on resource availability (nutrients and light) and mixed layer depth as ecological axes that define ecological niches of phytoplankton. We report fundamental differences in size distributions of marine and freshwater diatoms, with transitional water phytoplankton significantly smaller and with higher surface to volume ratio than marine species. Here, we hypothesize that mixing condition affecting size-dependent sinking may drive phytoplankton size and shape distributions. The interplay between shallow mixed layer depth and frequent and complete mixing of transitional waters may likely increase the competitive advantage of small phytoplankton limiting large cell fitness. The nutrient regime appears to explain the size distribution within both marine and transitional water environments, while it seem does not explain the pattern observed across the two environments. In addition, difference in light availability across the two environments appear do not explain the occurrence of asymmetric size distribution at each hierarchical level. We hypothesize that such competitive equilibria and adaptive strategies in resource exploitation may drive by organism’s behavior which exploring patch resources in transitional and marine phytoplankton communities. PMID:25974052

  11. Diversity distribution patterns of Chinese endemic seed plant species and their implications for conservation planning.

    Science.gov (United States)

    Huang, Jihong; Huang, Jianhua; Lu, Xinghui; Ma, Keping

    2016-09-23

    Endemism is an important concept in biogeography and biodiversity conservation. China is one of the richest countries in biodiversity, with very high levels of plant endemism. In this study, we analysed the distribution patterns of diversity, the degree of differentiation, and the endemicity of Chinese endemic seed plants using the floristic unit as a basic spatial analysis unit and 11 indices. The analysis was based on distribution data of 24,951 native seed plant species (excluding subspecies and varieties) and 12,980 Chinese endemic seed plant species, which were sourced from both specimen records and published references. The distribution patterns of Chinese endemic flora were generally consistent but disproportionate across China for diversity, degree of differentiation and endemicity. The South Hengduan Mountains Subregion had the highest values for all indices. At the regional level, both the Hengduan Mountains and the Central China regions were highest in diversity and degrees of differentiation. However, both the rate of local endemic to native species and the rate of local to Chinese endemic species were highest in the Taiwan Region and the South Taiwan Region. The Hengduan Mountains Region and the Central China Region are two key conservation priority areas for Chinese endemic seed plants.

  12. Quantitative analysis of CT attenuation distribution patterns of nodule components for pathologic categorization of lung nodules

    Science.gov (United States)

    Zhou, Chuan; Chan, Heang-Ping; Wei, Jun; Hadjiiski, Lubomir M.; Chughtai, Aamer; Kazerooni, Ella A.

    2017-03-01

    We investigated the feasibility of classifying pathologic invasive nodules and pre-invasive or benign nodules by quantitative analysis of the CT attenuation distribution patterns and other radiomic features of lung nodule components. We developed a new 3D adaptive multi-component Expectation-Maximization (EM) analysis method to segment the solid and non-solid nodule components and the surrounding lung parenchymal region. Features were extracted to characterize the size, shape, and the CT attenuation distribution of the entire nodule as well as the individual regions. With permission of the National Lung Screening Trial (NLST) project, a data set containing the baseline low dose CT scans of 53 cases with known pathologic tumor type categorization was obtained. The 53 cases contain 45 invasive nodules (group 1) and 42 pre-invasive nodules (group 2). A logistic regression model (LRM) was built using leave-one-case-out resampling and receiver operating characteristic (ROC) analysis for classification of group 1 and group 2, using the pathologic categorization as ground truth. With 4 selected features, the LRM achieved a test area under the curve (AUC) value of 0.877+/-0.036. The results demonstrated that the pathologic invasiveness of lung adenocarcinomas could be categorized according to the CT attenuation distribution patterns of the nodule components manifested on LDCT images.

  13. Diversity and Global Distribution of IncL/M Plasmids Enabling Horizontal Dissemination of β-Lactam Resistance Genes among the Enterobacteriaceae

    Directory of Open Access Journals (Sweden)

    Marcin Adamczuk

    2015-01-01

    Full Text Available Antibiotic resistance determinants are frequently associated with plasmids and other mobile genetic elements, which simplifies their horizontal transmission. Several groups of plasmids (including replicons of the IncL/M incompatibility group were found to play an important role in the dissemination of resistance genes encoding β-lactamases. The IncL/M plasmids are large, broad host range, and self-transmissible replicons. We have identified and characterized two novel members of this group: pARM26 (isolated from bacteria inhabiting activated sludge from a wastewater treatment plant and pIGT15 (originating from a clinical strain of Escherichia coli. This instigated a detailed comparative analysis of all available sequences of IncL/M plasmids encoding β-lactamases. The core genome of these plasmids is comprised of 20 genes with conserved synteny. Phylogenetic analyses of these core genes allowed clustering of the plasmids into four separate groups, which reflect their antibiotic resistance profiles. Examination of the biogeography of the IncL/M plasmids revealed that they are most frequently found in bacteria of the family Enterobacteriaceae originating from the Mediterranean region and Western Europe and that they are able to persist in various ecological niches even in the absence of direct antibiotic selection pressure.

  14. Factors controlling spatial distribution patterns of biocrusts in a heterogeneous and topographically complex semiarid area

    Science.gov (United States)

    Chamizo, Sonia; Rodríguez-Caballero, Emilio; Roncero, Beatriz; Raúl Román, José; Cantón, Yolanda

    2016-04-01

    Biocrusts are widespread soil components in drylands all over the world. They are known to play key roles in the functioning of these regions by fixing carbon and nitrogen, regulating hydrological processes, and preventing from water and wind erosion, thus reducing the loss of soil resources and increasing soil fertility. The rate and magnitude of services provided by biocrusts greatly depend on their composition and developmental stage. Late-successional biocrusts such as lichens and mosses have higher carbon and nitrogen fixation rates, and confer greater protection against erosion and the loss of sediments and nutrients than early-successional algae and cyanobacteria biocrusts. Knowledge of spatial distribution patterns of different biocrust types and the factors that control their distribution is important to assess ecosystem services provided by biocrusts at large spatial scales and to improve modelling of biogeochemical processes and water and carbon balance in drylands. Some of the factors that condition biocrust cover and composition are incoming solar radiation, terrain attributes, vegetation distribution patterns, microclimatic variables and soil properties such as soil pH, texture, soil organic matter, soil nutrients and gypsum and CaCO3 content. However, the factors that govern biocrust distribution may vary from one site to another depending on site characteristics. In this study, we examined the influence of abiotic attributes on the spatial distribution of biocrust types in a complex heterogeneous badland system (Tabernas, SE Spain) where biocrust cover up to 50% of the soil surface. From the analysis of relationships between terrain attributes and proportional abundance of biocrust types, it was found that topography exerted a main control on the spatial distribution of biocrust types in this area. SW-facing slopes were dominated by physical soil crusts and were practically devoid of vegetation and biocrusts. Biocrusts mainly occupied the pediments

  15. Mapping National Plant Biodiversity Patterns in South Korea with the MARS Species Distribution Model.

    Directory of Open Access Journals (Sweden)

    Hyeyeong Choe

    Full Text Available Accurate information on the distribution of existing species is crucial to assess regional biodiversity. However, data inventories are insufficient in many areas. We examine the ability of Multivariate Adaptive Regression Splines (MARS multi-response species distribution model to overcome species' data limitations and portray plant species distribution patterns for 199 South Korean plant species. The study models species with two or more observations, examines their contribution to national patterns of species richness, provides a sensitivity analysis of different range threshold cutoff approaches for modeling species' ranges, and presents considerations for species modeling at fine spatial resolution. We ran MARS models for each species and tested four threshold methods to transform occurrence probabilities into presence or absence range maps. Modeled occurrence probabilities were extracted at each species' presence points, and the mean, median, and one standard deviation (SD calculated to define data-driven thresholds. A maximum sum of sensitivity and specificity threshold was also calculated, and the range maps from the four cutoffs were tested using independent plant survey data. The single SD values were the best threshold tested for minimizing omission errors and limiting species ranges to areas where the associated occurrence data were correctly classed. Eight individual species range maps for rare plant species were identified that are potentially affected by resampling predictor variables to fine spatial scales. We portray spatial patterns of high species richness by assessing the combined range maps from three classes of species: all species, endangered and endemic species, and range-size rarity of all species, which could be used in conservation planning for South Korea. The MARS model is promising for addressing the common problem of few species occurrence records. However, projected species ranges are highly dependent on the

  16. Patterns, biases and prospects in the distribution and diversity of Neotropical snakes

    Science.gov (United States)

    Sawaya, Ricardo J.; Zizka, Alexander; Laffan, Shawn; Faurby, Søren; Pyron, R. Alexander; Bérnils, Renato S.; Jansen, Martin; Passos, Paulo; Prudente, Ana L. C.; Cisneros‐Heredia, Diego F.; Braz, Henrique B.; Nogueira, Cristiano de C.; Antonelli, Alexandre; Meiri, Shai

    2017-01-01

    Abstract Motivation We generated a novel database of Neotropical snakes (one of the world's richest herpetofauna) combining the most comprehensive, manually compiled distribution dataset with publicly available data. We assess, for the first time, the diversity patterns for all Neotropical snakes as well as sampling density and sampling biases. Main types of variables contained We compiled three databases of species occurrences: a dataset downloaded from the Global Biodiversity Information Facility (GBIF), a verified dataset built through taxonomic work and specialized literature, and a combined dataset comprising a cleaned version of the GBIF dataset merged with the verified dataset. Spatial location and grain Neotropics, Behrmann projection equivalent to 1° × 1°. Time period Specimens housed in museums during the last 150 years. Major taxa studied Squamata: Serpentes. Software format Geographical information system (GIS). Results The combined dataset provides the most comprehensive distribution database for Neotropical snakes to date. It contains 147,515 records for 886 species across 12 families, representing 74% of all species of snakes, spanning 27 countries in the Americas. Species richness and phylogenetic diversity show overall similar patterns. Amazonia is the least sampled Neotropical region, whereas most well‐sampled sites are located near large universities and scientific collections. We provide a list and updated maps of geographical distribution of all snake species surveyed. Main conclusions The biodiversity metrics of Neotropical snakes reflect patterns previously documented for other vertebrates, suggesting that similar factors may determine the diversity of both ectothermic and endothermic animals. We suggest conservation strategies for high‐diversity areas and sampling efforts be directed towards Amazonia and poorly known species. PMID:29398972

  17. Towards evenly distributed grazing patterns: including social context in sheep management strategies

    Directory of Open Access Journals (Sweden)

    Agustina di Virgilio

    2016-06-01

    Full Text Available Background. A large proportion of natural grasslands around the world is exposed to overgrazing resulting in land degradation and biodiversity loss. Although there is an increasing effort in the promotion of sustainable livestock management, rangeland degradation still occurs because animals’ foraging behaviour is highly selective at different spatial scales. The assessment of the ecological mechanisms modulating the spatial distribution of grazing and how to control it has critical implications for long term conservation of resources and the sustainability of livestock production. Considering the relevance of social interactions on animals’ space use patterns, our aim was to explore the potential effects of including animals’ social context into management strategies using domestic sheep grazing in rangelands as case study. Methods. We used GPS data from 19 Merino sheep (approximately 10% of the flock grazing on three different paddocks (with sizes from 80 to 1000 Ha during a year, to estimate resource selection functions of sheep grazing in flocks of different levels of heterogeneity. We assessed the effects of sheep class (i.e., ewes, wethers, and hoggets, age, body condition and time since release on habitat selection patterns. Results. We found that social rank was reflected on sheep habitat use, where dominant individuals (i.e., reproductive females used more intensively the most preferred areas and low-ranked (i.e., yearlings used less preferred areas. Our results showed that when sheep grazed on more heterogeneous flocks, grazing patterns were more evenly distributed at all the paddocks considered in this study. On the other hand, when high-ranked individuals were removed from the flock, low-ranked sheep shifted their selection patterns by increasing the use of the most preferred areas and strongly avoided to use less preferred sites (i.e., a highly selective grazing behaviour. Discussion. Although homogenization and segregation of

  18. Towards evenly distributed grazing patterns: including social context in sheep management strategies

    Science.gov (United States)

    Morales, Juan Manuel

    2016-01-01

    Background. A large proportion of natural grasslands around the world is exposed to overgrazing resulting in land degradation and biodiversity loss. Although there is an increasing effort in the promotion of sustainable livestock management, rangeland degradation still occurs because animals’ foraging behaviour is highly selective at different spatial scales. The assessment of the ecological mechanisms modulating the spatial distribution of grazing and how to control it has critical implications for long term conservation of resources and the sustainability of livestock production. Considering the relevance of social interactions on animals’ space use patterns, our aim was to explore the potential effects of including animals’ social context into management strategies using domestic sheep grazing in rangelands as case study. Methods. We used GPS data from 19 Merino sheep (approximately 10% of the flock) grazing on three different paddocks (with sizes from 80 to 1000 Ha) during a year, to estimate resource selection functions of sheep grazing in flocks of different levels of heterogeneity. We assessed the effects of sheep class (i.e., ewes, wethers, and hoggets), age, body condition and time since release on habitat selection patterns. Results. We found that social rank was reflected on sheep habitat use, where dominant individuals (i.e., reproductive females) used more intensively the most preferred areas and low-ranked (i.e., yearlings) used less preferred areas. Our results showed that when sheep grazed on more heterogeneous flocks, grazing patterns were more evenly distributed at all the paddocks considered in this study. On the other hand, when high-ranked individuals were removed from the flock, low-ranked sheep shifted their selection patterns by increasing the use of the most preferred areas and strongly avoided to use less preferred sites (i.e., a highly selective grazing behaviour). Discussion. Although homogenization and segregation of flocks by

  19. Distribution pattern of dorsal root ganglion neurons synthesizing nitric oxide synthase in different animal species.

    Science.gov (United States)

    Kolesár, Dalibor; Kolesárová, Mária; Kyselovič, Ján

    2017-04-01

    The main aim of the present review is to provide at first a short survey of the basic anatomical description of sensory ganglion neurons in relation to cell size, conduction velocity, thickness of myelin sheath, and functional classification of their processes. In addition, we have focused on discussing current knowledge about the distribution pattern of neuronal nitric oxide synthase containing sensory neurons especially in the dorsal root ganglia in different animal species; hence, there is a large controversy in relation to interpretation of the results dealing with this interesting field of research.

  20. [Study on distributed patterns of scoparone and ayapin in Dendrobium species from Yunnan].

    Science.gov (United States)

    Liu, Yan-Yan; Yu, Hong; Yuan, Feng; Zhou, Feng; Chen, Ye-Gao

    2013-11-01

    An HPLC method for determination of scoparone and ayapin was established for investigating the distributed patterns of scoparone and ayapin in 37 species of Dendrobium. The contents of scoparone and ayapin in varied collected samples were determined by the established HPLC method. The pseudo-bulbs sampled were collected according to different growth age of D. thyrsiflorum. The results showed that the contents of scoparone and ayapin were much differently distributed in species of Dendrobium. Only D. thyrsiflorum and D. densfilorum contained both scoparone and ayapin, the content decreased with the growth age. A fewer amount of ayapin was tested in D. loddigesii from Wenshan. The scoparone and ayapin were not determined in the rest species of Dendrobium. The method was concise, sensitive, accurate and reproducible. It could be applied to assay scoparone and ayapin in populations of herbal Dendrobium.

  1. The Tara Oceans voyage reveals global diversity and distribution patterns of marine planktonic ciliates

    Science.gov (United States)

    Gimmler, Anna; Korn, Ralf; de Vargas, Colomban; Audic, Stéphane; Stoeck, Thorsten

    2016-01-01

    Illumina reads of the SSU-rDNA-V9 region obtained from the circumglobal Tara Oceans expedition allow the investigation of protistan plankton diversity patterns on a global scale. We analyzed 6,137,350 V9-amplicons from ocean surface waters and the deep chlorophyll maximum, which were taxonomically assigned to the phylum Ciliophora. For open ocean samples global planktonic ciliate diversity is relatively low (ca. 1,300 observed and predicted ciliate OTUs). We found that 17% of all detected ciliate OTUs occurred in all oceanic regions under study. On average, local ciliate OTU richness represented 27% of the global ciliate OTU richness, indicating that a large proportion of ciliates is widely distributed. Yet, more than half of these OTUs shared oceanic carbonate system and temperature. Planktonic ciliates displayed distinct vertical distributions relative to chlorophyll a. In contrast, the Tara Oceans dataset did not reveal any evidence that latitude is structuring ciliate communities. PMID:27633177

  2. Petechiae: reproducible pattern of distribution and increased appearance after bed rest.

    Science.gov (United States)

    Ganse, Bergita; Limper, Ulrich; Bühlmeier, Judith; Rittweger, Jörn

    2013-08-01

    Exposure to acceleration can cause petechial hemorrhages, called G measles. Petechiae usually start to develop between 5 and 9 G with a high interindividual variance. Centrifuge training delays the onset to higher G levels. One might expect onset at lower G levels after bed rest; however, there is no evidence in the literature. A case of petechiae formation after bed rest is presented here. Orthostatic tolerance was tested using a tilt table and lower body negative pressure before and after bed rest in both campaigns of a 2 x 21-d bed rest study with 6 degrees head-down tilt. A 42-yr-old male Caucasian without any history of thrombosis, venous disease, hemorrhage, or petechiae, and with a negative thrombophilia screening, took part in the bed rest study as 1 out of 10 subjects. He was the only one to develop petechiae during the orthostatic tests after, but not before, bed rest in both campaigns. Petechiae were distributed throughout the lower legs and most pronounced at the shin in a stocking-like fashion, surprisingly reoccurring in an identical pattern of distribution. Petechiae appeared slowly over minutes during hyperemia. This case indicates that prolonged bed rest decreases the threshold for petechiae formation. A reproducible distribution pattern suggests that factors predisposing to petechiae formation keep their local distribution over time (possibly due to local vessel structures). Mechanisms of adaptation and interindividual variance are unclear. Findings are of clinical relevance as such cases might occur after prolonged bed rest in patients without need of expensive testing.

  3. Local knowledge, use pattern and geographical distribution of Moringa oleifera Lam. (Moringaceae) in Nigeria.

    Science.gov (United States)

    Popoola, Jacob O; Obembe, Olawole O

    2013-11-25

    All parts of Moringa oleifera are medicinally valuable with overlapping uses in treating myriads of ailments and diseases including body pains and weakness, fever, asthma, cough, blood pressure, arthritis, diabetes, epilepsy, wound, and skin infection. Moringa also has robust ability to challenge terminal diseases such as HIV/AIDs infections, chronic anemia, cancer, malaria and hemorrhage. The present study was to obtain ethnobotanical information on the use and local knowledge variation, geographical distribution, and to collect different landraces of Moringa oleifera from the different agro-ecological regions in Nigeria, for further studies. Ethnobotanical data were collected through face to face interviews, semi structured questionnaires and discussions with selected people who had knowledge about the plant. The fidelity level (FL %) and use value for different use categories of Moringa oleifera and its parts were estimated. The variation in ethnobotanical knowledge was evaluated by comparing the mean use value among ethnic, gender and age groups using sample T test. Garmi GPS was used to determine the locations (latitude and longitude) and height in different areas to assess the geographical spread of the species. Seven (7) categories of use (Food, medicine, fodder, fencing, firewood, gum and coagulant) were recorded for Moringa oleifera. Food and medicinal uses showed highest fidelity level while the leaves and the seeds were the plant parts most utilized for the same purposes. There were significant differences among the ethnic, gender and age groups regarding the ethno-botanical use value. The geographical distribution pattern shows that the Moringa oleifera is well distributed in all ecological zones of Nigeria, well adapted to the varied climatic conditions and gaining unprecedented awareness among the people. Though considered an introduced species, Moringa oleifera has found wide acceptance, recognition and usefulness among the various ethnicities in the

  4. Common distribution patterns of marsupials related to physiographical diversity in Venezuela.

    Science.gov (United States)

    Ventura, Jacint; Bagaria, Guillem; Sans-Fuentes, Maria Assumpció; Pérez-Hernández, Roger

    2014-01-01

    The aim of this study is to identify significant biotic regions (groups of areas with similar biotas) and biotic elements (groups of taxa with similar distributions) for the marsupial fauna in a part of northern South America using physiographical areas as Operational Geographical Units (OGUs). We considered Venezuela a good model to elucidate this issue because of its high diversity in landscapes and the relatively vast amount of information available on the geographical distribution of marsupial species. Based on the presence-absence of 33 species in 15 physiographical sub-regions (OGUs) we identified Operational Biogeographical Units (OBUs) and chorotypes using a quantitative analysis that tested statistical significance of the resulting groups. Altitudinal and/or climatic trends in the OBUs and chorotypes were studied using a redundancy analysis. The classification method revealed four OBUs. Strong biotic boundaries separated: i) the xerophytic zone of the Continental coast (OBU I); ii) the sub-regions north of the Orinoco River (OBU III and IV); and those south to the river (OBU II). Eleven chorotypes were identified, four of which included a single species with a restricted geographic distribution. As for the other chorotypes, three main common distribution patterns have been inferred: i) species from the Llanos and/or distributed south of the Orinoco River; ii) species exclusively from the Andes; and iii) species that either occur exclusively north of the Orinoco River or that show a wide distribution throughout Venezuela. Mean altitude, evapotranspiration and precipitation of the driest month, and temperature range allowed us to characterize environmentally most of the OBUs and chorotypes obtained.

  5. Horizontal and vertical distribution of Chaetognatha in the upper 1000 m of the western Sargasso Sea and the Central and South-east Atlantic.

    Digital Repository Service at National Institute of Oceanography (India)

    Pierrot-Bultsa, A.C.; Nair, V.R.

    The chaetognath abundance, species richness and bathymetric distribution in the upper 1000 m in two regions of the Atlantic Ocean is discussed based on samples collected on two cruises, one to the Sargasso Sea (Northwest Atlantic) on board the R/V R...

  6. Calibration of a distributed hydrologic model using observed spatial patterns from MODIS data

    Science.gov (United States)

    Demirel, Mehmet C.; González, Gorka M.; Mai, Juliane; Stisen, Simon

    2016-04-01

    Distributed hydrologic models are typically calibrated against streamflow observations at the outlet of the basin. Along with these observations from gauging stations, satellite based estimates offer independent evaluation data such as remotely sensed actual evapotranspiration (aET) and land surface temperature. The primary objective of the study is to compare model calibrations against traditional downstream discharge measurements with calibrations against simulated spatial patterns and combinations of both types of observations. While the discharge based model calibration typically improves the temporal dynamics of the model, it seems to give rise to minimum improvement of the simulated spatial patterns. In contrast, objective functions specifically targeting the spatial pattern performance could potentially increase the spatial model performance. However, most modeling studies, including the model formulations and parameterization, are not designed to actually change the simulated spatial pattern during calibration. This study investigates the potential benefits of incorporating spatial patterns from MODIS data to calibrate the mesoscale hydrologic model (mHM). This model is selected as it allows for a change in the spatial distribution of key soil parameters through the optimization of pedo-transfer function parameters and includes options for using fully distributed daily Leaf Area Index (LAI) values directly as input. In addition the simulated aET can be estimated at a spatial resolution suitable for comparison to the spatial patterns observed with MODIS data. To increase our control on spatial calibration we introduced three additional parameters to the model. These new parameters are part of an empirical equation to the calculate crop coefficient (Kc) from daily LAI maps and used to update potential evapotranspiration (PET) as model inputs. This is done instead of correcting/updating PET with just a uniform (or aspect driven) factor used in the mHM model

  7. Distribution and transport patterns of northern rock sole, Lepidopsetta polyxystra, larvae in the southeastern Bering Sea

    Science.gov (United States)

    Lanksbury, Jennifer A.; Duffy-Anderson, Janet T.; Mier, Kathryn L.; Busby, Morgan S.; Stabeno, Phyllis J.

    2007-01-01

    We report the size, abundance, and distribution (horizontal, vertical) of northern rock sole, Lepidopsetta polyxystra, larvae collected from ichthyoplankton surveys on the southeastern Bering Sea shelf near Unimak Island, in Unimak Pass, and in the Gulf of Alaska south of Unimak Island. The greatest abundances of larvae occurred within Unimak Pass and in the Bering Sea northeast of Unimak Island. Larvae were smaller and more abundant in 2002 than in 2003. Larval abundance and size varied with depth. Highest abundances were at depths of 10-30 m during the day, and larger fish appeared to migrate from below 20 m to 0-10 m at night. There was evidence of multiple spawning locales and larval dispersal pathways that were depth- and area-specific. Northern rock sole larvae spawned west of Unimak Pass along the Aleutian Islands may be transported northward by the Bering Slope Current. Larvae spawned in the Gulf of Alaska and advected through Unimak Pass are differentially dispersed, primarily to the middle and outer shelves along the 100 m and 200 m isobaths, or along the Alaska Peninsula. Larvae spawned along the Alaska Peninsula east of Unimak Island appear to have the greatest chance of being transported to nursery areas in the coastal domain. Dispersal of near-surface northern rock sole larvae in any of these locations is likely influenced by wind-driven advection, but below-surface (>10 m) northern rock sole larval transport is probably more affected by factors that modulate geostrophic flow rather than wind-driven surface currents.

  8. Spatial patterns and frequency distributions of regional deformation in the healthy human lung.

    Science.gov (United States)

    Hurtado, Daniel E; Villarroel, Nicolás; Andrade, Carlos; Retamal, Jaime; Bugedo, Guillermo; Bruhn, Alejandro

    2017-08-01

    Understanding regional deformation in the lung has long attracted the medical community, as parenchymal deformation plays a key role in respiratory physiology. Recent advances in image registration make it possible to noninvasively study regional deformation, showing that volumetric deformation in healthy lungs follows complex spatial patterns not necessarily shared by all subjects, and that deformation can be highly anisotropic. In this work, we systematically study the regional deformation in the lungs of eleven human subjects by means of in vivo image-based biomechanical analysis. Regional deformation is quantified in terms of 3D maps of the invariants of the right stretch tensor, which are related to regional changes in length, surface and volume. Based on the histograms of individual lungs, we show that log-normal distributions adequately represent the frequency distribution of deformation invariants in the lung, which naturally motivates the normalization of the invariant fields in terms of the log-normal score. Normalized maps of deformation invariants allow for a direct intersubject comparison, as they display spatial patterns of deformation in a range that is common to all subjects. For the population studied, we find that lungs in supine position display a marked gradient along the gravitational direction not only for volumetric but also for length and surface regional deformation, highlighting the role of gravity in the regional deformation of normal lungs under spontaneous breathing.

  9. Type 2 diabetes mellitus patients manifest characteristic spatial EMG potential distribution pattern during sustained isometric contraction.

    Science.gov (United States)

    Watanabe, Kohei; Miyamoto, Toshiaki; Tanaka, Yoji; Fukuda, Kazuhito; Moritani, Toshio

    2012-09-01

    The purpose of the present study is to investigate spatial surface electromyography (SEMG) potential distribution pattern in type 2 diabetes mellitus (T2DM) patients. Nine T2DM patients and nine age-matched healthy men (CON) performed a sustained isometric knee extension at 10% of maximal voluntary contraction for 120s. Multi-channel SEMG was recorded from the vastus lateralis muscle by means of 64 electrodes. To characterize spatial SEMG potential distribution pattern, modified entropy and correlation coefficients between same electrode locations were calculated at 15, 60 and 120s for the root mean square values. At 60 and 120s, modified entropy in T2DM was significantly lower than those in CON (p<0.05). Correlation coefficients for T2DM were significantly higher than those for CON at 60 and 120s (p<0.05). From these results, we suggested that T2DM patients continue to recruit limited and same motor units during the sustained contraction at low force level. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  10. The Upper Mississippi River floodscape: spatial patterns of flood inundation and associated plant community distributions

    Science.gov (United States)

    DeJager, Nathan R.; Rohweder, Jason J.; Yin, Yao; Hoy, Erin E.

    2016-01-01

    Questions How is the distribution of different plant communities associated with patterns of flood inundation across a large floodplain landscape? Location Thirty-eight thousand nine hundred and seventy hectare of floodplain, spanning 320 km of the Upper Mississippi River (UMR). Methods High-resolution elevation data (Lidar) and 30 yr of daily river stage data were integrated to produce a ‘floodscape’ map of growing season flood inundation duration. The distributions of 16 different remotely sensed plant communities were quantified along the gradient of flood duration. Results Models fitted to the cumulative frequency of occurrence of different vegetation types as a function of flood duration showed that most types exist along a continuum of flood-related occurrence. The diversity of community types was greatest at high elevations (0–10 d of flooding), where both upland and lowland community types were found, as well as at very low elevations (70–180 d of flooding), where a variety of lowland herbaceous communities were found. Intermediate elevations (20–60 d of flooding) tended to be dominated by floodplain forest and had the lowest diversity of community types. Conclusions Although variation in flood inundation is often considered to be the main driver of spatial patterns in floodplain plant communities, few studies have quantified flood–vegetation relationships at broad scales. Our results can be used to identify targets for restoration of historical hydrological regimes or better anticipate hydro-ecological effects of climate change at broad scales.

  11. Habitat Preferences, Distribution Pattern, and Root Weight Estimation of Pasak Bumi (Eurycoma longifolia Jack.

    Directory of Open Access Journals (Sweden)

    Siti Masitoh Kartikawati

    2014-04-01

    Full Text Available Pasak bumi (Eurycoma longifolia Jack is one of non timber forest products with “indeterminate” conservation status and commercially traded in West Kalimantan. The research objective was to determine the potential of pasak bumi root per hectare and its ecological condition under natural habitat. Root weight of E. longifolia Jack was estimated using simple linear regression and exponential equation with stem diameter and height as independent variables. The results showed that the individual number of the population was 114 with the majority in seedling stage with 71 individuals (62.28%. The distribution was found in clumped pattern. Conditions of the habitat could be described as follows: daily average temperature of 25.6oC, daily average relative humidity of 73.6%, light intensity of 0.9 klx, and red-yellow podsolic soil with texture ranged from clay to sandy clay. The selected estimator model for E. longifolia Jack root weight used exponential equation with stem height as independent variable using the equation of Y= 21.99T0,010 and determination coefficient of 0.97. After height variable was added, the potential of E. longifolia Jack minimum root weight that could be harvested per hectare was 0.33 kg.Keywords: Eurycoma longifolia, habitat preference, distribution pattern, root weight

  12. Optimizing Client Latency in a Distributed System by Using the “Remote Façade” Design Pattern

    Directory of Open Access Journals (Sweden)

    Cosmin RABLOU

    2010-01-01

    Full Text Available In this paper we investigate the role of the Remote Façade pattern in the optimization of dis-tributed systems. The intent of this pattern is to wrap fine-grained remote objects in a coarse-grained interface and thus greatly reduce the total number of calls executed over the network. The measurement of the performance gain achieved by implementing this pattern is done through testing with a distributed application written in C# and using the latest Microsoft framework for distributed systems (Windows Communication Framework. Furthermore, we will be presenting the scenarios in which the implementation of the Remote Façade pattern brings a significant performance gain. Finally we show further scenarios in which the per-formance brought by this pattern can be investigated.

  13. Spatial distribution patterns of the peppery furrow shell Scrobicularia plana (da Costa, 1778) along the European coast: A review

    Science.gov (United States)

    Santos, Sílvia; Luttikhuizen, Pieternella C.; Campos, Joana; Heip, Carlo H. R.; van der Veer, Henk W.

    2011-10-01

    The bivalve Scrobicularia plana is an important species of shallow water benthic communities with a wide geographic distribution but also with a general patchy pattern, i.e. irregular in occurrence and in density. This review aims to determine the processes responsible for the species' spatial distribution pattern based on the available information on S. plana. Although several pre- and post-settlement processes are believed to influence spatial patterns of marine invertebrates, the general patchy distribution of S. plana seems to be determined by the existence of specific environmental conditions during settlement. Factors such as temperature, salinity, sediment type, hydrographic conditions and predation affect settlement and spat survival and not one but a combination of factors seems to explain the species distribution pattern. Future work should focus on determining the scale of patchiness, using hierarchical sampling, as well as the connectivity between populations by analysing the population genetic structure.

  14. Modeling the Spatial Distribution and Fruiting Pattern of a Key Tree Species in a Neotropical Forest: Methodology and Potential Applications

    National Research Council Canada - National Science Library

    Caillaud, Damien; Crofoot, Margaret C; Scarpino, Samuel V; Jansen, Patrick A; Garzon-Lopez, Carol X; Winkelhagen, Annemarie J. S; Bohlman, Stephanie A; Walsh, Peter D

    2010-01-01

    ... distributions of food resources. We illustrate our procedure by creating a detailed simulation model of fruit production patterns for Dipteryx oleifera, a keystone tree species, on Barro Colorado Island (BCI), Panama...

  15. Vertical and horizontal distribution of zooplankton and polar cod in southern Baffin Bay (66-71°N) in September 2009

    DEFF Research Database (Denmark)

    Kjellerup, Sanne; Dünweber, Michael; Møller, Eva Friis

    2015-01-01

    Zooplankton are the link connecting primary producers to higher trophic levels, and knowing their distribution and community is important for predicting the distribution of predator species, like fish, seabirds, and marine mammals. However, data from open Arctic oceans are still scarce. In autumn...... fishes in the upper 500 m of southern Baffin Bay in September 2009. The zooplankton community was dominated by copepods (55 % of abundance in the upper 500 m), primarily of the genus Calanus. Other important zooplankton taxa included Limacina helicina, Chaetognatha, and Cirripedia nauplii...... predators such as seabirds and fish. The acoustic survey showed the highest density of polar cod Boreogadus saida in the upper 50 m on the western part of the Greenland Shelf. A particularly high biomass of both zooplankton and polar cod was found in the central part of the basin in association with a local...

  16. Strain distribution across magmatic margins during the breakup stage: Seismicity patterns in the Afar rift zone

    Science.gov (United States)

    Brown, C.; Ebinger, C. J.; Belachew, M.; Gregg, T.; Keir, D.; Ayele, A.; Aronovitz, A.; Campbell, E.

    2008-12-01

    Fault patterns record the strain history along passive continental margins, but geochronological constraints are, in general, too sparse to evaluate these patterns in 3D. The Afar depression in Ethiopia provides a unique setting to evaluate the time and space relations between faulting and magmatism across an incipient passive margin that formed above a mantle plume. The margin comprises a high elevation flood basalt province with thick, underplated continental crust, a narrow fault-line escarpment underlain by stretched and intruded crust, and a broad zone of highly intruded, mafic crust lying near sealevel. We analyze fault and seismicity patterns across and along the length of the Afar rift zone to determine the spatial distribution of strain during the final stages of continental breakup, and its relation to active magmatism and dike intrusions. Seismicity data include historic data and 2005-2007 data from the collaborative US-UK-Ethiopia Afar Geodynamics Project that includes the 2005-present Dabbahu rift episode. Earthquake epicenters cluster within discrete, 50 km-long magmatic segments that lack any fault linkage. Swarms also cluster along the fault-line scarp between the unstretched and highly stretched Afar rift zone; these earthquakes may signal release of stresses generated by large lateral density contrasts. We compare Coulomb static stress models with focal mechanisms and fault kinematics to discriminate between segmented magma intrusion and crank- arm models for the central Afar rift zone.

  17. Large-scale spatial distribution patterns of gastropod assemblages in rocky shores.

    Directory of Open Access Journals (Sweden)

    Patricia Miloslavich

    Full Text Available Gastropod assemblages from nearshore rocky habitats were studied over large spatial scales to (1 describe broad-scale patterns in assemblage composition, including patterns by feeding modes, (2 identify latitudinal pattern of biodiversity, i.e., richness and abundance of gastropods and/or regional hotspots, and (3 identify potential environmental and anthropogenic drivers of these assemblages. Gastropods were sampled from 45 sites distributed within 12 Large Marine Ecosystem regions (LME following the NaGISA (Natural Geography in Shore Areas standard protocol (www.nagisa.coml.org. A total of 393 gastropod taxa from 87 families were collected. Eight of these families (9.2% appeared in four or more different LMEs. Among these, the Littorinidae was the most widely distributed (8 LMEs followed by the Trochidae and the Columbellidae (6 LMEs. In all regions, assemblages were dominated by few species, the most diverse and abundant of which were herbivores. No latitudinal gradients were evident in relation to species richness or densities among sampling sites. Highest diversity was found in the Mediterranean and in the Gulf of Alaska, while highest densities were found at different latitudes and represented by few species within one genus (e.g. Afrolittorina in the Agulhas Current, Littorina in the Scotian Shelf, and Lacuna in the Gulf of Alaska. No significant correlation was found between species composition and environmental variables (r≤0.355, p>0.05. Contributing variables to this low correlation included invasive species, inorganic pollution, SST anomalies, and chlorophyll-a anomalies. Despite data limitations in this study which restrict conclusions in a global context, this work represents the first effort to sample gastropod biodiversity on rocky shores using a standardized protocol across a wide scale. Our results will generate more work to build global databases allowing for large-scale diversity comparisons of rocky intertidal assemblages.

  18. Distinct distribution patterns of prokaryotes between sediment and water in the Yellow River estuary.

    Science.gov (United States)

    Wei, Guangshan; Li, Mingcong; Li, Fenge; Li, Han; Gao, Zheng

    2016-11-01

    There are close exchanges between sediment and water in estuaries; however, the patterns of prokaryotic community assembly in these two habitat types are still unclear. This study investigated the bacterial and archaeal abundance, diversity, and community composition in the sediment and the overlying water of the Yellow River estuary. Notably higher prokaryotic abundance and diversity were detected in the sediment than in the water, and bacterial abundance and diversity were remarkably higher than those of archaea. Furthermore, the ratio of bacterial to archaeal 16S rRNA gene abundance was significantly lower in the sediment than in the water. Bacterial communities at different taxonomic levels were apparently distinct between the sediment and water, but archaeal communities were not. The most dominant bacteria were affiliated with Deltaproteobacteria and Gammaproteobacteria in sediment and with Alphaproteobacteria and Betaproteobacteria in water. Euryarchaeota and Thaumarchaeota were the most abundant archaea in both habitats. Although distinct prokaryotic distribution patterns were observed, most of the dominant bacteria and archaea present were related to carbon, nitrogen, and sulfur cycling processes, such as methanogenesis, ammonia oxidation, and sulfate reduction. Unexpectedly, prokaryotes from the water showed a higher sensitivity to environmental factors, while only a few factors affected sediment communities. Additionally, some potential co-occurrence relationships between prokaryotes were also found in this study. These results suggested distinct distribution patterns of bacterial and archaeal communities between sediment and overlying water in this important temperate estuary, which may serve as a useful community model for the further ecological and evolutionary study of prokaryotes in estuarine ecosystems.

  19. Distribution patterns of muscle fibre types in major muscles of the bull (Bos taurus).

    Science.gov (United States)

    Totland, G K; Kryvi, H

    1991-01-01

    The study describes the variations in distribution and cross-sectional area (fibre size) of three muscle fibre types (I, IIA, IIB) in 34 of the largest muscles of the bull (Bos taurus). The animals had been kept strictly unexercised for one year before slaughter. Representative sampling was done at 15 positions within each muscle, and from 2700 to 4500 fibres were analysed in each muscle. Different intermuscular patterns are described. The overall volume fraction (%) of type I fibres was about 10% higher in the forepart muscles than in the hindpart muscles (41% and 31%, respectively), while the mean content of type IIB fibres was similar. Type I fibres were particularly abundant in antigravity muscles. Of these, the hindlimb muscles contained 50% more type I fibres (by weight) than those of the forelimb. Typical antigravity antagonists contained very few type I fibres. In the thigh cross-section the proportion of type I fibres was highest in the anterior and medial parts, while the IIB fibres tended to be concentrated in the superficial and posterior parts. Intramuscular patterns were revealed, with type I fibres becoming gradually more abundant from superficial to deep regions, while IIB fibres had an opposite distribution. This was particularly evident in the thigh proper and in the scapular region. Within each fasciculus of all the muscles, the muscle fibre types formed a general spatial pattern. Type I fibres in the muscles of the forepart were on average about 15% larger than those of the muscles in the hindpart. The IIB fibres were on average about 10% larger in the hindpart than in the forepart muscles. A covariation between the proportion of type I and IIB fibres and their cross-sectional area was indicated.

  20. Spatio-temporal patterns in acoustic presence and distribution of Antarctic blue whales Balaenoptera musculus intermedia in the Weddell Sea

    OpenAIRE

    Thomisch, Karolin; Boebel, Olaf; Clark, CW; Hagen, W.; Spiesecke, Stefanie; Zitterbart, Daniel; Van Opzeeland, Ilse

    2016-01-01

    Distribution and movement patterns of Antarctic blue whales Balaenoptera musculus intermedia at large temporal and spatial scales are still poorly understood. The objective of this study was to explore spatio-temporal distribution patterns of Antarctic blue whales in the Atlantic sector of the Southern Ocean, using passive acoustic monitoring data. Multi-year data were collected between 2008 and 2013 by 11 recorders deployed in the Weddell Sea and along the Greenwich meridian. Antarctic blue ...

  1. Acoustic surveys for juvenile anchovy in the Bay of Biscay: Abundance estimate as an indicator of the next year's recruitment and spatial distribution patterns

    KAUST Repository

    Boyra, Guillermo

    2013-08-16

    A series of acoustic surveys (JUVENA) began in 2003 targeting juvenile anchovy (Engraulis encrasicolus) in the Bay of Biscay. A specific methodology was designed for mapping and estimating juvenile abundance annually, four months after the spawning season. After eight years of the survey, a consistent picture of the spatial pattern of the juvenile anchovy has emerged. Juveniles show a vertical and horizontal distribution pattern that depends on size. The younger individuals are found isolated from other species in waters closer to the surface, mainly off the shelf within the mid-southern region of the bay. The largest juveniles are usually found deeper and closer to the shore in the company of adult anchovy and other pelagic species. In these eight years, the survey has covered a wide range of juvenile abundances, and the estimates show a significant positive relationship between the juvenile biomasses and the one-year-old recruits of the following year. This demonstrates that the JUVENA index provides an early indication of the strength of next year\\'s recruitment to the fishery and can therefore be used to improve the management advice for the fishery of this short-lived species. © 2013 International Council for the Exploration of the Sea.

  2. Predicting the distribution pattern of small carnivores in response to environmental factors in the Western Ghats.

    Directory of Open Access Journals (Sweden)

    Riddhika Kalle

    Full Text Available Due to their secretive habits, predicting the pattern of spatial distribution of small carnivores has been typically challenging, yet for conservation management it is essential to understand the association between this group of animals and environmental factors. We applied maximum entropy modeling (MaxEnt to build distribution models and identify environmental predictors including bioclimatic variables, forest and land cover type, topography, vegetation index and anthropogenic variables for six small carnivore species in Mudumalai Tiger Reserve. Species occurrence records were collated from camera-traps and vehicle transects during the years 2010 and 2011. We used the average training gain from forty model runs for each species to select the best set of predictors. The area under the curve (AUC of the receiver operating characteristic plot (ROC ranged from 0.81 to 0.93 for the training data and 0.72 to 0.87 for the test data. In habitat models for F. chaus, P. hermaphroditus, and H. smithii "distance to village" and precipitation of the warmest quarter emerged as some of the most important variables. "Distance to village" and aspect were important for V. indica while "distance to village" and precipitation of the coldest quarter were significant for H. vitticollis. "Distance to village", precipitation of the warmest quarter and land cover were influential variables in the distribution of H. edwardsii. The map of predicted probabilities of occurrence showed potentially suitable habitats accounting for 46 km(2 of the reserve for F. chaus, 62 km(2 for V. indica, 30 km(2 for P. hermaphroditus, 63 km(2 for H. vitticollis, 45 km(2 for H. smithii and 28 km(2 for H. edwardsii. Habitat heterogeneity driven by the east-west climatic gradient was correlated with the spatial distribution of small carnivores. This study exemplifies the usefulness of modeling small carnivore distribution to prioritize and direct conservation planning for habitat specialists

  3. Simulating water distribution patterns for fixed spray plate sprinkler using the ballistic theory

    Directory of Open Access Journals (Sweden)

    Sofiane Ouazaa

    2014-07-01

    Full Text Available Ballistic simulation of the spray sprinkler for self-propelled irrigation machines requires the incorporation of the effect of the jet impact with the deflecting plate. The kinetic energy losses produced by the jet impact with the spray plate were experimentally characterized for different nozzle sizes and two working pressures for fixed spray plate sprinklers (FSPS. A technique of low speed photography was used to determine drop velocity at the point where the jet is broken into droplets. The water distribution pattern of FSPS for different nozzle sizes, working at two pressures and under different wind conditions were characterized in field experiments. The ballistic model was calibrated to simulate water distribution in different technical and meteorological conditions. Field experiments and the ballistic model were used to obtain the model parameters (D50, n, K1and K2. The results show that kinetic energy losses decrease with nozzle diameter increments; from 80% for the smallest nozzle diameter (2 mm to 45% for nozzle diameters larger than 5.1 mm, and from 80% for the smallest nozzle diameter (2 mm to 34.7% for nozzle diameters larger than 6.8 mm, at 138 kPa and 69 kPa working pressures, respectively. The results from the model compared well with field observations. The calibrated model has reproduced accurately the water distribution pattern in calm (r=0.98 and high windy conditions (r=0.76. A new relationship was found between the corrector parameters (K1’ and K2’ and the wind speed. As a consequence, model simulation will be possible for untested meteorological conditions.

  4. Habitat characteristics predicting distribution and abundance patterns of scallops in D'Entrecasteaux Channel, Tasmania.

    Science.gov (United States)

    Mendo, Tania; Lyle, Jeremy M; Moltschaniwskyj, Natalie A; Tracey, Sean R; Semmens, Jayson M

    2014-01-01

    Habitat characteristics greatly influence the patterns of distribution and abundance in scallops, providing structure for the settlement of spat and influencing predation risk and rates of survival. Establishing scallop-habitat relationships is relevant to understanding the ecological processes that regulate scallop populations and to managing critical habitats. This information is particularly relevant for the D'Entrecasteaux Channel, south-eastern Tasmania (147.335 W, 43.220 S), a region that has supported significant but highly variable scallop production over many years, including protracted periods of stock collapse. Three species of scallops are present in the region; the commercial scallop Pecten fumatus, the queen scallop Equichlamys bifrons, and the doughboy scallop Mimachlamys asperrima. We used dive surveys and Generalized Additive Modelling to examine the relationship between the distribution and abundance patterns of each species and associated habitat characteristics. The aggregated distribution of each species could be predicted as a function of sediment type and species-specific habitat structural components. While P. fumatus was strongly associated with finer sediments and E. bifrons with coarse grain sediments, M. asperrima had a less selective association, possibly related to its ability to attach on a wide range of substrates. Other habitat characteristics explaining P. fumatus abundance were depth, Asterias amurensis abundance, shell and macroalgae cover. Equichlamys bifrons was strongly associated with macroalgae and seagrass cover, whereas M. asperrima abundance was greatly explained by sponge cover. The models define a set of relationships from which plausible hypotheses can be developed. We propose that these relationships are mediated by predation pressure as well as the specific behavioural characteristics of each species. The findings also highlight the specific habitat characteristics that are relevant for spatial management and habitat

  5. Habitat characteristics predicting distribution and abundance patterns of scallops in D'Entrecasteaux Channel, Tasmania.

    Directory of Open Access Journals (Sweden)

    Tania Mendo

    Full Text Available Habitat characteristics greatly influence the patterns of distribution and abundance in scallops, providing structure for the settlement of spat and influencing predation risk and rates of survival. Establishing scallop-habitat relationships is relevant to understanding the ecological processes that regulate scallop populations and to managing critical habitats. This information is particularly relevant for the D'Entrecasteaux Channel, south-eastern Tasmania (147.335 W, 43.220 S, a region that has supported significant but highly variable scallop production over many years, including protracted periods of stock collapse. Three species of scallops are present in the region; the commercial scallop Pecten fumatus, the queen scallop Equichlamys bifrons, and the doughboy scallop Mimachlamys asperrima. We used dive surveys and Generalized Additive Modelling to examine the relationship between the distribution and abundance patterns of each species and associated habitat characteristics. The aggregated distribution of each species could be predicted as a function of sediment type and species-specific habitat structural components. While P. fumatus was strongly associated with finer sediments and E. bifrons with coarse grain sediments, M. asperrima had a less selective association, possibly related to its ability to attach on a wide range of substrates. Other habitat characteristics explaining P. fumatus abundance were depth, Asterias amurensis abundance, shell and macroalgae cover. Equichlamys bifrons was strongly associated with macroalgae and seagrass cover, whereas M. asperrima abundance was greatly explained by sponge cover. The models define a set of relationships from which plausible hypotheses can be developed. We propose that these relationships are mediated by predation pressure as well as the specific behavioural characteristics of each species. The findings also highlight the specific habitat characteristics that are relevant for spatial

  6. Distribution patterns of macrofaunal species diversity in subtidal soft sediments: biodiversity-productivity relationships from the MacroBen database

    NARCIS (Netherlands)

    Escaravage, V.L.; Herman, P.M.J.; Merckx, B.; Bodarska-Kowalczuk, M.W.; Amouroux, J.M.; Degraer, S.; Grémare, A.; Heip, C.H.R.; Hummel, H.; Karakassis, I.; Labrune, C.; Willems, W.

    2009-01-01

    We analyzed patterns of species diversity in a compiled data set covering the European coast (from Norway to Crete) that was made available in the framework of the MarBEF European Network of Excellence. The focus was on the distribution patterns of species diversity over large areas across Europe.

  7. Positive and negative feedbacks and free-scale pattern distribution in rural-population dynamics.

    Directory of Open Access Journals (Sweden)

    Concepción L Alados

    Full Text Available Depopulation of rural areas is a widespread phenomenon that has occurred in most industrialized countries, and has contributed significantly to a reduction in the productivity of agro-ecological resources. In this study, we identified the main trends in the dynamics of rural populations in the Central Pyrenees in the 20th C and early 21st C, and used density independent and density dependent models and identified the main factors that have influenced the dynamics. In addition, we investigated the change in the power law distribution of population size in those periods. Populations exhibited density-dependent positive feedback between 1960 and 2010, and a long-term positive correlation between agricultural activity and population size, which has resulted in a free-scale population distribution that has been disrupted by the collapse of the traditional agricultural society and by emigration to the industrialized cities. We concluded that complex socio-ecological systems that have strong feedback mechanisms can contribute to disruptive population collapses, which can be identified by changes in the pattern of population distribution.

  8. Links of the significant wave height distribution in the Mediterranean sea with the Northern Hemisphere teleconnection patterns

    Directory of Open Access Journals (Sweden)

    P. Lionello

    2008-06-01

    Full Text Available This study analyzes the link between the SWH (Significant Wave Height distribution in the Mediterranean Sea during the second half of the 20th century and the Northern Hemisphere SLP (Sea Level Pressure teleconnection patterns.

    The SWH distribution is computed using the WAM (WAve Model forced by the surface wind fields provided by the ERA-40 reanalysis for the period 1958–2001. The time series of mid-latitude teleconnection patterns are downloaded from the NOAA web site. This study shows that several mid-latitude patterns are linked to the SWH field in the Mediterranean, especially in its western part during the cold season: East Atlantic Pattern (EA, Scandinavian Pattern (SCA, North Atlantic Oscillation (NAO, East Atlantic/West Russia Pattern (EA/WR and East Pacific/ North Pacific Pattern (EP/NP. Though the East Atlantic pattern exerts the largest influence, it is not sufficient to characterize the dominant variability. NAO, though relevant, has an effect smaller than EA and comparable to other patterns. Some link results from possibly spurious structures. Patterns which have a very different global structure are associated to similar spatial features of the wave variability in the Mediterranean Sea. These two problems are, admittedly, shortcomings of this analysis, which shows the complexity of the response of the Mediterranean SWH to global scale SLP teleconnection patterns.

  9. Distribution Pattern of Earthquake-induced Landslides Triggered by the 12 May 2008 Wenchuan Earthquake

    Science.gov (United States)

    van Westen, Cees; Gorum, Tolga; Fan, Xuanmei; Qiu Huang, Run; Xu, Qiang; Tang, Chuang

    2010-05-01

    The catastrophic 12 May 2008 Wenchuan earthquake (Mw=7.9) occurred on the NE-SW trending Longmenshan fault zone at the eastern margin of the Tibetan Plateau, just west of the Sichuan basin, China. This extraordinary event triggered a large number of landslides, rock avalanches and debris flows, causing fatalities of more than 80,000, more than 374,176 people injured and serious economic loss. Our work shows the preliminary results of an extensive study on the mapping of the distribution of landslides triggered by the earthquake. An extensive landslide interpretation was carried out using a large set of optical high resolution satellite images (e.g. ASTER, ALOS, Cartosat-1, SPOT-5 and IKONOS) as well as air photos for both the pre- and post-earthquake situation. Landslide scarps were mapped as points using multi-temporal visual image interpretation taking into account shape, tone, texture, pattern, elevation and ridge and valley orientation. Nearly 60,000 individual landslide scarps were mapped. The landslide distribution map was compared with the inventory map that was prepared directly after the earthquake, which contains about 11,000 individual landslide points, through the calculation of normalized landslide isopleths maps. Remarkable differences were observed, as the earlier inventory mapping didn't consider the pre-earthquake situation and did not consider all individual landslides. As part of the landslide inventory, all landslides were identified that had blocked the drainage and had formed landslide dams. Detailed event-based landslide dam inventory map was prepared to show the landslide dam distribution and characteristics. The landslide distribution was compared with a number of aspects, such as the seismic parameters (distance to epicenter, distance to fault rupture, co-seismic fault geometry and co-seismic slip rate distribution), and geology. The most remarkable correlation found was with the co-seismic slip rate distribution and the fault geometry

  10. Investigating vertical distribution patterns of lower tropospheric PM2.5 using unmanned aerial vehicle measurements

    Science.gov (United States)

    Li, Xiao-Bing; Wang, Dong-Sheng; Lu, Qing-Chang; Peng, Zhong-Ren; Wang, Zhan-Yong

    2018-01-01

    A lightweight unmanned aerial vehicle (UAV) was outfitted with miniaturized sensors to investigate the vertical distribution patterns and sources of fine aerosol particles (PM2.5) within the 1 000 m lower troposphere. A total of 16 UAV flights were conducted in the Yangtze River Delta (YRD) region, China, from the summer to winter in 2014. The associated ground-level measurements from two environmental monitoring stations were also used for background analysis. The results show that ground-level PM2.5 concentrations demonstrated a decreasing trend from Feb. to Jul. and an increasing trend from Aug. to Jan. (the following year). Higher PM2.5 concentrations during the day were mainly observed in the morning (Local Time, LT 05-09) in the spring and summer. However, higher PM2.5 concentrations occurred mainly in the late afternoon and evening (LT 16-20) in the autumn and winter, excluding severe haze pollution days when higher PM2.5 concentrations were also observed during the morning periods. Lower tropospheric PM2.5 concentrations exhibited similar diurnal vertical distribution patterns from the summer to winter. The PM2.5 concentrations decreased with height in the morning, with significantly large vertical gradients from the summer to winter. By contrast, the aerosol particles were well mixed with PM2.5 concentrations of lower than 35 μg ṡm-3 in the early afternoon (LT 12-16) due to sufficient expansions of the planetary boundary layer. The mean vertical PM2.5 concentrations within the 1 000 m lower troposphere in the morning were much larger in the winter (∼87.5 μg ṡm-3) than in the summer and autumn (∼20 μg ṡm-3). However, subtle differences of ∼11 μg ṡm-3 in the mean vertical PM2.5 concentrations were observed in the early afternoon from the summer to winter. The vertical distribution patterns of black carbon and its relationships with PM2.5 indicated that the lower tropospheric aerosol particles might be mainly derived from fossil

  11. Wind-driven Snow Distribution Patterns Over an Antarctic Ice Floe

    Science.gov (United States)

    Trujillo, E.; Leonard, K. C.; Maksym, T.; Lehning, M.

    2015-12-01

    Sea ice, snow and atmosphere interactions are major drivers of the spatial distribution of snow over sea ice in polar regions. Here, we combine measurements of the wind flow, atmospheric conditions and blowing snow at two locations on an Antarctic sea ice floe, with terrestrial laser scanning to characterize a blowing snow storm and its influence on the spatial patterns of snow distribution at resolutions of 1-10 cm over an area of 100 m x 100 m. The datasets were obtained during the SIPEX II (Sea Ice Physics and Ecosystem eXperiment II) research voyage to East Antarctica (September-November 2012). The pre-storm surface (2012-10-20) exhibits multi-directional elongated snow dunes behind aerodynamic obstacles likely formed during previous snowstorms. The post-storm surface (2012-10-23) exhibits clear new deposition dunes elongated along the predominant wind direction. The new deposition areas amount to 38% of the total surveyed area. Patterns of erosion are less evident but cover a larger portion of the area. This results in a total volume of change near zero with a mean elevation difference of 0.02 m indicating that net erosion or deposition from snowfall was small despite of large mass relocation. After the storm, the statistical distributions of elevation and the 2D correlation functions remain similar to those of the pre-storm surface. The pre- and post-storm surfaces also exhibit power-law relationships in the power spectrum with little change between pre- and post-storm slopes. These observations suggest that despite the significant change observed in the snow surface patterns, the change does not translate into significant changes in the spatial statistical and scaling properties of the surface morphology. Such an observation is important for sea-ice model representations of the sub-pixel variability of sea ice surfaces, particularly between snowstorm events, although more datasets will be required to extend these results to a wider range of sea ice surface

  12. Computational Fluid Dynamics Study on the Influence of Airflow Patterns on Carbon Dioxide Distribution in a Scaled Livestock Building

    DEFF Research Database (Denmark)

    Rong, Li; Nielsen, Peter V.; Tong, Guohong

    2008-01-01

    has been applied to simulate the contaminant distribution. Experiments of tracer gas concentration distribution in the chamber are performed at Air Physic Lab of Aarhus University to validate CFD software. Simulation results and measurements show that ventilation rates and airflow patterns have...

  13. Woody plant encroachment into grasslands: spatial patterns of functional group distribution and community development.

    Science.gov (United States)

    Liu, Feng; Archer, Steven R; Gelwick, Frances; Bai, Edith; Boutton, Thomas W; Wu, Xinyuan Ben

    2013-01-01

    Woody plant encroachment into grasslands has been globally widespread. The woody species invading grasslands represent a variety of contrasting plant functional groups and growth forms. Are some woody plant functional types (PFTs) better suited to invade grasslands than others? To what extent do local patterns of distribution and abundance of woody PFTs invading grasslands reflect intrinsic topoedaphic properties versus plant-induced changes in soil properties? We addressed these questions in the Southern Great Plains, United States at a subtropical grassland known to have been encroached upon by woody species over the past 50-100 years. A total of 20 woody species (9 tree-statured; 11 shrub-statured) were encountered along a transect extending from an upland into a playa basin. About half of the encroaching woody plants were potential N2-fixers (55% of species), but they contributed only 7% to 16 % of the total basal area. Most species and the PFTs they represent were ubiquitously distributed along the topoedaphic gradient, but with varying abundances. Overstory-understory comparisons suggest that while future species composition of these woody communities is likely to change, PFT composition is not. Canonical correspondence analysis (CCA) ordination and variance partitioning (Partial CCA) indicated that woody species and PFT composition in developing woody communities was primarily influenced by intrinsic landscape location variables (e.g., soil texture) and secondarily by plant-induced changes in soil organic carbon and total nitrogen content. The ubiquitous distribution of species and PFTs suggests that woody plants are generally well-suited to a broad range of grassland topoedaphic settings. However, here we only examined categorical and non-quantitative functional traits. Although intrinsic soil properties exerted more control over the floristics of grassland-to-woodland succession did plant modifications of soil carbon and nitrogen concentrations, the latter

  14. Spatio-temporal variations in bloom of the red-tide dinoflagellate Karenia mikimotoi in Imari Bay, Japan, in 2014: Factors controlling horizontal and vertical distribution.

    Science.gov (United States)

    Aoki, Kazuhiro; Kameda, Takahiko; Yamatogi, Toshifumi; Ishida, Naoya; Hirae, Sou; Kawaguchi, Mayumi; Syutou, Toshio

    2017-11-15

    A massive bloom of the dinoflagellate Karenia mikimotoi appeared in 2014 in Imari Bay, Japan. Bloom dynamics and hydrographical conditions were examined by field survey. The bloom initially developed in the eastern area of Imari Bay, subsequently after rainfall during the neap tides, cell density exceeded over 10,000cellsml. Vertical distribution of K. mikimotoi was primarily controlled by the light intensity and secondarily by the water quality during the daytime. Almost all cell-density maxima occurred in depths with weak daytime light intensities of <300μmolm(-2)s(-1). In some cases of weak light intensity, cell-density maxima occurred in depths with favorable hydrodynamic conditions for the growth. Spatially classified areas were identified by cluster analysis using the growth rate calculated from seawater temperature and salinity. This study quantitatively evaluated the environmental factors of the eastern area, where the bloom initially occurred, during the development of the bloom. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. A distribution pattern of cadmium, gadolinium and samarium in Phaseolus vulgaris (L) plants as assessed by dynamic neutron radiography

    Science.gov (United States)

    Kőrösi, Ferenc; Balaskó, Márton; Sváb, Erzsébet

    1999-11-01

    The qualitative and semi-quantitative distributions, presumably apoplast transport patterns for the Gd, Sm and Cd were investigated in the primordial leaf tissues of the bean using dynamic neutron radiography. According to the applied 3D, 2D images and the pixel count distribution histograms of the considered gray levels, peculiar distribution patterns were postulated for the elements. Main and lateral vascular systems for Gd, the cell walls as well as intercellular spaces for Sm and the main leaf vein for Cd assumed to be the apoplast transport spaces and volumes.

  16. Species distributions and climate change:current patterns and future scenarios for biodiversity

    DEFF Research Database (Denmark)

    Hof, Christian

    extinction, one might assume that most species may also be able to successfully cope with contemporary climate change. However, current ecosystems are heavily modified by humans. Among other factors, habitat destruction and fragmentation caused by anthropogenic land-use changes negatively affect species...... orders. The ability to successfully track climatic changes depends on dispersal, which is in turn influenced by ecological adaptations, such as the affiliation with a certain habitat type. A common hypothesis is that species adapted to less persistent habitats have evolved stronger dispersal abilities....... Two studies of my thesis provide evidence for this hypothesis: (1) geographical distributions of dragonflies adapted to less persistent habitats show higher degrees of equilibrium with climatic conditions; (2) spatial patterns of European freshwater species richness and turnover differ strongly among...

  17. Effects of different shoe-lacing patterns on dorsal pressure distribution during running and perceived comfort.

    Science.gov (United States)

    Hagen, Marco; Hömme, Ann-Kathrin; Umlauf, Tim; Hennig, Ewald M

    2010-07-01

    The purpose of this study was to investigate the effects of four lacing patterns (one regular, one tight, and two seven-eyelet lacings) on dorsal foot pressures during running and the perception of comfort and stability with 14 male rearfoot runners. By using a pressure insole, peak dorsal pressures were measured under the shoe's tongue. Highest peak pressures were found above the talus, the navicular bone, and the first ray. Seven-eyelet lacings showed a significant enhancement of perceived stability without differences in perceived comfort compared with a regular six-eyelet technique. Reduction of pressure on the talus, the navicular bone, and the extensor tendons is related to better comfort. With individually chosen special seven-eyelet lacings runners can improve foot-shoe coupling without increasing peak dorsal pressures on the tarsus. Knowledge of the location of the dorsal pressure distribution is useful for new tongue and lacing constructions to improve comfort in running shoes while maintaining stability.

  18. Geospatial analysis and distribution patterns of home nursing care in a metropolitan area - a large-scale analysis.

    Science.gov (United States)

    Bauer, Jan; Reinhard, Julia; Boll, Michael; Groneberg, David

    2017-01-01

    This study focuses on home nursing care distribution in an urban setting in Germany. A shortage of nursing care workforce is present in Germany. A geospatial analysis was performed to examine distribution patterns at the district level in Frankfurt, Germany (n = 46 districts) and factors were analysed influencing the location choice of home nursing care providers (n = 151). Furthermore, within the analysis we focused on the population aged over 65 years to model the demand for nursing care. The analysis revealed a tendency of home nursing care providers to be located near the city centre (centripetal distribution pattern). However, the demand for care showed more inconsistent patterns. Still, a centripetal distribution pattern of demand could be stated. Compared with the control groups (e.g. acute hospitals and pharmacies) similar geographical distribution patterns were present. However, the location of home nursing care providers was less influenced by demand compared with the control groups. The supply of nursing care was unevenly distributed in this metropolitan setting, but still matched the demand for nursing care. Due to the rapidly changing health care environments policy, regulations must be (re-)evaluated critically to improve the management and delivery of nursing care provision. © 2016 John Wiley & Sons Ltd.

  19. Large-scale spatial distribution patterns of echinoderms in nearshore rocky habitats.

    Directory of Open Access Journals (Sweden)

    Katrin Iken

    Full Text Available This study examined echinoderm assemblages from nearshore rocky habitats for large-scale distribution patterns with specific emphasis on identifying latitudinal trends and large regional hotspots. Echinoderms were sampled from 76 globally-distributed sites within 12 ecoregions, following the standardized sampling protocol of the Census of Marine Life NaGISA project (www.nagisa.coml.org. Sample-based species richness was overall low (2 cm in 1 m(2 quadrats was highest in the Caribbean ecoregions and echinoids dominated these assemblages with an average of 5 ind m(-2. In contrast, intertidal echinoderm assemblages collected from clearings of 0.0625 m(2 quadrats had the highest abundance and richness in the Northeast Pacific ecoregions where asteroids and holothurians dominated with an average of 14 ind 0.0625 m(-2. Distinct latitudinal trends existed for abundance and richness in intertidal assemblages with declines from peaks at high northern latitudes. No latitudinal trends were found for subtidal echinoderm assemblages with either sampling technique. Latitudinal gradients appear to be superseded by regional diversity hotspots. In these hotspots echinoderm assemblages may be driven by local and regional processes, such as overall productivity and evolutionary history. We also tested a set of 14 environmental variables (six natural and eight anthropogenic as potential drivers of echinoderm assemblages by ecoregions. The natural variables of salinity, sea-surface temperature, chlorophyll a, and primary productivity were strongly correlated with echinoderm assemblages; the anthropogenic variables of inorganic pollution and nutrient contamination also contributed to correlations. Our results indicate that nearshore echinoderm assemblages appear to be shaped by a network of environmental and ecological processes, and by the differing responses of various echinoderm taxa, making generalizations about the patterns of nearshore rocky habitat echinoderm

  20. Diversity and Distribution Patterns of Cetaceans in the Subtropical Southwestern Atlantic Outer Continental Shelf and Slope.

    Directory of Open Access Journals (Sweden)

    Juliana Couto Di Tullio

    Full Text Available Temporal and spatial patterns of cetacean diversity and distribution were investigated through eight ship-based surveys carried out during spring and autumn between 2009 and 2014 on the outer continental shelf (~150m and slope (1500m off southeastern and southern Brazil (~23°S to ~34°S. The survey area was divided into southeast and south areas according to their oceanographic characteristics. Twenty-one species were observed in 503 sightings. The overall number of species was similar between the two areas, though it was higher in the spring in the south area. Five species were dominant and diversity varied more seasonally than spatially. ANOVA and kernel analyses showed that overall cetacean densities were higher in spring compared to autumn. Physeter macrocephalus, the most frequent species, concentrated throughout the south area at depths over 1000m in both seasons. Despite the overlapped occurrence at a broader scale, small delphinids presented latitudinal and in-offshore gradients as well as seasonal variation in distribution patterns, which could indicate habitat partitioning between some species. Delphinus delphis was only recorded in the south and its density decreased in areas where the presence of Stenella frontalis increased, mainly beyond the 250m isobath. Densities of S. longirostris and S. attenuata increased in lower latitudes and beyond the shelf break. The large delphinids Tursiops truncatus and Globicephala melas formed mixed groups in many occasions and were observed along the study area around depths of 500m. Grampus griseus was twice as frequent in the south area and densities increased in waters deeper than 600m. As expected, densities of both small and large migratory whales were higher during spring, over the continental slope, in the southeast area. The results presented here provided strong evidence on the importance of the outer continental shelf and slope to a diverse community of cetaceans occurring in the

  1. Diversity and Distribution Patterns of Cetaceans in the Subtropical Southwestern Atlantic Outer Continental Shelf and Slope.

    Science.gov (United States)

    Di Tullio, Juliana Couto; Gandra, Tiago B R; Zerbini, Alexandre N; Secchi, Eduardo R

    2016-01-01

    Temporal and spatial patterns of cetacean diversity and distribution were investigated through eight ship-based surveys carried out during spring and autumn between 2009 and 2014 on the outer continental shelf (~150m) and slope (1500m) off southeastern and southern Brazil (~23°S to ~34°S). The survey area was divided into southeast and south areas according to their oceanographic characteristics. Twenty-one species were observed in 503 sightings. The overall number of species was similar between the two areas, though it was higher in the spring in the south area. Five species were dominant and diversity varied more seasonally than spatially. ANOVA and kernel analyses showed that overall cetacean densities were higher in spring compared to autumn. Physeter macrocephalus, the most frequent species, concentrated throughout the south area at depths over 1000m in both seasons. Despite the overlapped occurrence at a broader scale, small delphinids presented latitudinal and in-offshore gradients as well as seasonal variation in distribution patterns, which could indicate habitat partitioning between some species. Delphinus delphis was only recorded in the south and its density decreased in areas where the presence of Stenella frontalis increased, mainly beyond the 250m isobath. Densities of S. longirostris and S. attenuata increased in lower latitudes and beyond the shelf break. The large delphinids Tursiops truncatus and Globicephala melas formed mixed groups in many occasions and were observed along the study area around depths of 500m. Grampus griseus was twice as frequent in the south area and densities increased in waters deeper than 600m. As expected, densities of both small and large migratory whales were higher during spring, over the continental slope, in the southeast area. The results presented here provided strong evidence on the importance of the outer continental shelf and slope to a diverse community of cetaceans occurring in the subtropical Southwestern

  2. Large-scale spatial distribution patterns of echinoderms in nearshore rocky habitats.

    Science.gov (United States)

    Iken, Katrin; Konar, Brenda; Benedetti-Cecchi, Lisandro; Cruz-Motta, Juan José; Knowlton, Ann; Pohle, Gerhard; Mead, Angela; Miloslavich, Patricia; Wong, Melisa; Trott, Thomas; Mieszkowska, Nova; Riosmena-Rodriguez, Rafael; Airoldi, Laura; Kimani, Edward; Shirayama, Yoshihisa; Fraschetti, Simonetta; Ortiz-Touzet, Manuel; Silva, Angelica

    2010-11-05

    This study examined echinoderm assemblages from nearshore rocky habitats for large-scale distribution patterns with specific emphasis on identifying latitudinal trends and large regional hotspots. Echinoderms were sampled from 76 globally-distributed sites within 12 ecoregions, following the standardized sampling protocol of the Census of Marine Life NaGISA project (www.nagisa.coml.org). Sample-based species richness was overall low (species per site), with a total of 32 asteroid, 18 echinoid, 21 ophiuroid, and 15 holothuroid species. Abundance and species richness in intertidal assemblages sampled with visual methods (organisms >2 cm in 1 m(2) quadrats) was highest in the Caribbean ecoregions and echinoids dominated these assemblages with an average of 5 ind m(-2). In contrast, intertidal echinoderm assemblages collected from clearings of 0.0625 m(2) quadrats had the highest abundance and richness in the Northeast Pacific ecoregions where asteroids and holothurians dominated with an average of 14 ind 0.0625 m(-2). Distinct latitudinal trends existed for abundance and richness in intertidal assemblages with declines from peaks at high northern latitudes. No latitudinal trends were found for subtidal echinoderm assemblages with either sampling technique. Latitudinal gradients appear to be superseded by regional diversity hotspots. In these hotspots echinoderm assemblages may be driven by local and regional processes, such as overall productivity and evolutionary history. We also tested a set of 14 environmental variables (six natural and eight anthropogenic) as potential drivers of echinoderm assemblages by ecoregions. The natural variables of salinity, sea-surface temperature, chlorophyll a, and primary productivity were strongly correlated with echinoderm assemblages; the anthropogenic variables of inorganic pollution and nutrient contamination also contributed to correlations. Our results indicate that nearshore echinoderm assemblages appear to be shaped by a

  3. Lifetime earnings patterns, the distribution of future Social Security benefits, and the impact of pension reform.

    Science.gov (United States)

    Bosworth, B; Burtless, G; Steuerle, E

    2000-01-01

    In order to assess the effect of Social Security reform on current and future workers, it is essential to accurately characterize the initial situations of representative workers affected by reform. For the purpose of analyzing typical reforms, the most important characteristic of a worker is the level and pattern of his or her preretirement earnings. Under the current system, pensions are determined largely by the level of the workers' earnings averaged over their work life. However, several reform proposals would create individual retirement accounts for which the pension would depend on the investment accumulation within the account. Thus, the pension would also depend on the timing of the contributions into the account and hence on the exact shape of the worker's lifetime earnings profile. Most analysis of the distributional impact of reform has focused, however, on calculating benefit changes among a handful of hypothetical workers whose relative earnings are constant over their work life. The earnings levels are not necessarily chosen to represent the situations of workers who have typical or truly representative earnings patterns. Consequently, the results of such analysis can be misleading, especially if reform involves introducing a fundamentally new kind of pension formula. This article presents two broad approaches to creating representative earnings profiles for policy evaluation. First, we use standard econometric methods to predict future earnings for a representative sample of workers drawn from the Survey of Income and Program Participation (SIPP). Our statistical estimates are based on a simple representation of typical career earnings paths and a fixed-effect statistical specification. Because our estimation file contains information on each worker's annual earnings from 1951 through 1996 as reported in the Social Security Administration's earnings files, we have a record (though an incomplete one) of the actual earnings that will be used to

  4. Distribuição horizontal e taxas de crescimento, senescência e desfolhação de azevém perene e festuca, puros e em associação Horizontal distribution and growth, senescence and defoliation fluxes of perennial ryegrass and tall fescue pure and mixed swards

    Directory of Open Access Journals (Sweden)

    Andréa Machado Groff

    2002-09-01

    Full Text Available O experimento foi realizado no INRA (Institut National de la Recherche Agronomique em Theix, França. Duas gramíneas (azevém perene e festucaforam semeadas em caixas (0,13 m² usando-se três distribuições horizontais do pasto (pura, linhas alternadas e faixas alternadas e três intervalos de desfolhações (3,5, 7 e 14 dias, com quatro repetições por tratamento. Quatro meses após a semeadura, a cada data de desfolhação, as caixas foram oferecidas, individualmente, a quatro ovelhas secas e retiradas após a realização de 340 bocados.m-2. Para cada gramínea estudaram-se a densidade populacional e a massa de perfilhos, a altura e a produção de matéria seca, a profundidade e a massa do bocado e as taxas de crescimento, senescência e desfolhação. A maior altura do pasto, gerada por desfolhações menos freqüentes, promoveu a realização de bocados mais profundos e de maior massa. Por outro lado, em desfolhações mais freqüentes a altura do pasto foi mantida mais baixa, e a profundidade e massa do bocado foram menores. A distribuição horizontal das plantas promoveu respostas diferenciadas em relação as taxas de crescimento, senescência e desfolhação. Quando em linhas alternadas a festuca teve a taxa de crescimento limitada, provavelmente desfavorecida pela competição.The experiment was carried in INRA (Institut National de la Recherche Agronomique at Theix, France. Two grasses (perennial ryegrass and tall fescue were grown in sward boxes (0,13 m², using three different sward horizontal distribution (pure, alternate rows and alternate strips and three defoliation intervals (3,5, 7 and 14 days between two successive defoliation with four replications. Four months after sowing, at defoliation date, sward boxes were offered to four individual dry ewes and removed after 340 bites.m-2 had been taken. For each grass species, the population density and the tiller mass, sward height, herbage production, bite depth and bite mass

  5. Distributed Patterns of Brain Activity Underlying Real-Time fMRI Neurofeedback Training.

    Science.gov (United States)

    Kopel, Rotem; Emmert, Kirsten; Scharnowski, Frank; Haller, Sven; Van De Ville, Dimitri

    2017-06-01

    Neurofeedback (NF) based on real-time functional magnetic resonance imaging (rt-fMRI) is an exciting neuroimaging application. In most rt-fMRI NF studies, the activity level of a single region of interest (ROI) is provided as a feedback signal and the participants are trained to up or down regulate the feedback signal. NF training effects are typically analyzed using a confirmatory univariate approach, i.e., changes in the target ROI are explained by a univariate linear modulation. However, learning to self-regulate the ROI activity through NF is mediated by distributed changes across the brain. Here, we deploy a multivariate decoding model for assessing NF training effects across the whole brain. Specifically, we first explain the NF training effect by a posthoc multivariate model that leads to a pattern of coactivation based on 90 functional atlas regions. We then use cross validation to reveal the set of brain regions with the best fit. This novel approach was applied to the data from a rt-fMRI NF study where the participants learned to down regulate the auditory cortex. We found that the optimal model consisted of 16 brain regions whose coactivation patterns best described the training effect over the NF training days. Cross validation of the multivariate model showed that it generalized across the participants. Interestingly, the participants could be clustered into two groups with distinct patterns of coactivation, potentially reflecting different NF learning strategies. Overall, our findings revealed that multiple brain regions are involved in learning to regulate an activity in a single ROI, and thus leading to a better understanding of the mechanisms underlying NF training.

  6. Horizontal and vertical distribution of sea lice larvae (Lepeophtheirus salmonis) in and around salmon farms in the Bay of Fundy, Canada.

    Science.gov (United States)

    Nelson, E J; Robinson, S M C; Feindel, N; Sterling, A; Byrne, A; Pee Ang, K

    2017-11-21

    The sea louse, Lepeophtheirus salmonis, is parasitic to salmonid species in the Northern Hemisphere and has become a widespread biological and economic problem for the salmon farming industry. A better understanding is needed of their spatial distribution and early life history to disrupt the life cycle of the sea louse. In this study, sea lice larval densities within salmon farms, between salmon farms and reference sites, and at various depths were quantified using both plankton pumps and plankton nets. Farm sites exhibited significantly higher densities than reference sites; however, these densities dropped an order of magnitude at a distance of 100 m from the cages. The majority of the larvae captured in the study were nauplii (93%), and densities ranged from 0 to 10 larvae/m3 . Free-swimming sea lice larvae were found to exhibit a diel cycle where nauplii larvae were in deeper waters (10-17 m) during the day and in surface waters (1-6 m) during the night. The results of this study suggest that the early life-history stages of sea lice originate from and may remain close to active salmon farms, creating a self-sustaining population. © 2017 Her Majesty the Queen in Right of Canada. Journal of Fish Diseases © 2017 John Wiley & Sons Ltd Reproduced with the permission of the Minister of Fisheries and Oceans of Canada.

  7. Horizontal and Vertical Distribution of Heavy Metals in Farm Produce and Livestock around Lead-Contaminated Goldmine in Dareta and Abare, Zamfara State, Northern Nigeria

    Directory of Open Access Journals (Sweden)

    O. E. Orisakwe

    2017-01-01

    Full Text Available Background. Hitherto studies in response to the June 2010 lead poisoning, Zamfara State, Nigeria, have focused on clinical interventions without information on livestock and other metals. Objective. This study has investigated the distribution of heavy metals in farm produce and livestock around lead-contaminated goldmine in Dareta and Abare, Zamfara State, Nigeria. Methods. Vegetables, soil, water, blood, and different meat samples were harvested from goat, sheep, cattle, and chicken from Dareta, Abare, and Gusau communities. The samples were digested with 10 mL of a mix of nitric and perchloric acids; the mixture was then heated to dryness. Lead, cadmium, zinc, chromium, copper, magnesium, and nickel were analysed using flame Atomic Absorption Spectrophotometer. The daily intake, bioaccumulation factor, and target hazard quotient (THQ were calculated. Results. Chicken bone-muscles from Dareta had the highest concentrations of lead, zinc, and nickel (28.2750, 16.1650, and 4.2700 mg/kg, resp., while chicken brain had the highest levels of cadmium, magnesium (0.3800 and 67.5400 mg/kg, and chromium (6.1650 mg/kg, kidney tissue inclusive. Conclusion. In addition to lead, cadmium may also be of concern in the contaminated mining communities of Zamfara State, Nigeria, given the high levels of cadmium in meat and vegetables samples from these areas.

  8. Horizontal and Vertical Distribution of Heavy Metals in Farm Produce and Livestock around Lead-Contaminated Goldmine in Dareta and Abare, Zamfara State, Northern Nigeria

    Science.gov (United States)

    Oladipo, O. O.; Ajaezi, G. C.; Udowelle, N. A.

    2017-01-01

    Background. Hitherto studies in response to the June 2010 lead poisoning, Zamfara State, Nigeria, have focused on clinical interventions without information on livestock and other metals. Objective. This study has investigated the distribution of heavy metals in farm produce and livestock around lead-contaminated goldmine in Dareta and Abare, Zamfara State, Nigeria. Methods. Vegetables, soil, water, blood, and different meat samples were harvested from goat, sheep, cattle, and chicken from Dareta, Abare, and Gusau communities. The samples were digested with 10 mL of a mix of nitric and perchloric acids; the mixture was then heated to dryness. Lead, cadmium, zinc, chromium, copper, magnesium, and nickel were analysed using flame Atomic Absorption Spectrophotometer. The daily intake, bioaccumulation factor, and target hazard quotient (THQ) were calculated. Results. Chicken bone-muscles from Dareta had the highest concentrations of lead, zinc, and nickel (28.2750, 16.1650, and 4.2700 mg/kg, resp.), while chicken brain had the highest levels of cadmium, magnesium (0.3800 and 67.5400 mg/kg), and chromium (6.1650 mg/kg, kidney tissue inclusive). Conclusion. In addition to lead, cadmium may also be of concern in the contaminated mining communities of Zamfara State, Nigeria, given the high levels of cadmium in meat and vegetables samples from these areas. PMID:28539940

  9. The dynamics of mercury near Idrija mercury mine, Slovenia: Horizontal and vertical distributions of total, methyl, and ethyl mercury concentrations in soils.

    Science.gov (United States)

    Tomiyasu, Takashi; Kodamatani, Hitoshi; Imura, Ryusuke; Matsuyama, Akito; Miyamoto, Junko; Akagi, Hirokatsu; Kocman, David; Kotnik, Jože; Fajon, Vesna; Horvat, Milena

    2017-10-01

    The distributions of the total mercury (T-Hg), methylmercury (MeHg), and ethylmercury (EtHg) concentrations in soil and their relationship to chemical composition of the soil and total organic carbon content (TOC, %) were investigated. Core samples were collected from hill slope on the right and left riverbanks of the Idrija River. Former smelting plant is located on the right bank. The T-Hg average in each of the core samples ranged from 0.25 to 1650 mg kg -1 . The vertical T-Hg variations in the samples from the left bank showed no significant change with depth. Conversely, the T-Hg varied with depth, with the surface, or layers several centimeters from the surface, tending to show the highest values in the samples from the right bank. Since the right and left bank soils have different chemical compositions, different pathways of mercury delivery into soils were suggested. The MeHg and EtHg concentrations ranged from n.d. (not detected) to 444 μg kg -1 and n.d. to 17.4 μg kg -1 , respectively. The vertical variations of MeHg and EtHg were similar to those of TOC, except for the near-surface layers containing TOC greater than 20%. These results suggest that the decomposition of organic matter is closely related to organic mercury formation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Horizontal and vertical distribution of mesozooplankton species richness and composition down to 2,300 m in the southwest Atlantic Ocean

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    Sérgio L.C. Bonecker

    2014-10-01

    Full Text Available We describe the species richness, distribution and composition of mesozooplankton over the continental shelf and slope, and in the water masses in the Campos Basin, southwest Atlantic Ocean. We analyzed the mesozooplankton from two oceanographic cruises (rainy and dry seasons, 2009 with samples taken in five different water masses from the surface to 2,300 m depth. In the Subsurface Water (SS, in both sampling periods, more species were recorded over the slope (rainy: 100; dry: 128 than the continental shelf (rainy: 97; dry: 104. Over the slope, species richness decreased with increasing depth: the highest values were observed in the South Atlantic Central Water (SACW, and the lowest values in the North Atlantic Deep Water (NADW, in both sampling periods. We recorded 262 species in 10 groups (Hydrozoa, Siphonophora, Ctenophora, Branchiopoda, Copepoda, Euphausiacea, Decapoda, Chaetognatha, Appendicularia e Thaliacea, with 13 new occurrences for the southwest Atlantic. Copepoda was the group with the highest species richness, containing 138 species. In both periods, the samples from SS, SACW and Antarctic Intermediate Water (AAIW/Upper Circumpolar Deep Water (UCDW were clustered in different faunistic zones, based on species composition. This study confirmed that zooplankton richness in the southwest Atlantic Ocean is underestimated, and suggests that additional efforts must be directed toward a better understanding of this fairly unknown region.

  11. Gastrointestinal lymphoma in Western Algeria: pattern of distribution and histological subtypes (retrospective study).

    Science.gov (United States)

    Zeggai, Soumia; Harir, Noria; Tou, Abdenacer; Medjamia, Miloud; Guenaoui, Khaira

    2016-12-01

    Primary gastrointestinal (GI) lymphomas (GIL) are uncommon diseases that can involve the whole GI tract. Considerable variation exists in the literature with respect to incidence of the various histological subtypes and sites of involvement. This study was undertaken to establish the anatomic distribution, histological subtypes and sites of GI lymphomas of patients from Western Algeria. The case records of 58 consecutive patients with GIL diagnosed at the Pathologies Departments of Algerian west region (the Military Hospital of Oran city and the Central University Hospital of Sidi Bel Abbes city) from January 2006 to December 2013 were retrospectively evaluated for epidemiology and histopathology report. All lymphomas were reclassified according to the WHO 2008 classification. A total of 58 patients (39 male, 19 female) with mean age of 61 years and a range of 20-89 years were included in this study. Stomach was the most common site involved (70.7%). The commonest histological subtype was mucosa-associated lymphoid tissue (MALT) B cell lymphoma (46.6%), followed by diffuse large B-cell lymphomas (DLBCL) (43.1%).The frequency of Helicobacter pylori (HP) positivity differ between gastric and intestinal location P=0.003 and correlates with the histological type P=0.01. This retrospective study of patients with GI lymphoma from Western Algeria illustrates the pattern of distribution of various common and rare histological subtypes. More studies are necessary to find a potential cause, risk factor or genetic mutation that can explain these specific characteristics of GIL.

  12. Cadmium and polychlorinated biphenyls: Different distribution pattern in North Sea Benthic biota

    Science.gov (United States)

    Everaarts, J. M.; Otter, E.; Fischer, C. V.

    Whole-body concentrations of cadmium in the shrimp Crangon allmanni and the starfish Asterias rubens were significantly higher in specimens collected from areas north and northeast of the Dogger Bank than in other areas of the North Sea studied. In the brown shrimp Crangon crangon, whose distribution is restricted to the estuarine and coastal zone, the cadmium concentration was found to be significantly lower than in C. allmanni and did not vary with sampling site. The cadmium concentrations in shrimp increased from the estuarine area (including the Dutch Wadden Sea) to the coastal zone and Southern Bight of the North Sea and again to the open central North Sea (Dogger Bank). Concentrations of the total of 50 polychlorinated biphenyl congeners ( Σ50-CB) were higher in Crangon crangon and Asterias rubens occurring in the coastal zone of the Southern Bight than in specimens of the central and northern part of the Dutch continental shelf. The Σ50-CB concentration in the shrimp Crangon allmanni was considerably lower than in the closely related species C. crangon. Thus, cadmium and PCBs showed different distribution patterns in North Sea benthic invertebrates: highest concentrations of Σ50-CB were restricted to estuarine and coastal areas and highest concentrations of cadmium were found in the open sea (central North Sea, north of the Dogger Bank).

  13. Controls on morphological variability and role of stream power distribution pattern, Yamuna River, western India

    Science.gov (United States)

    Bawa, Nupur; Jain, Vikrant; Shekhar, Shashank; Kumar, Niraj; Jyani, Vikas

    2014-12-01

    Understanding the controls on the morphological variability of river systems constitutes one of the fundamental questions in geomorphic investigation. Channel morphology is an important indicator of river processes and is of significance for mapping the hydrology-ecologic connectivity in a river system and for predicting the future trajectory of river health in response to external forcings. This paper documents the spatial morphological variability and its natural and anthropogenic controls for the Yamuna River, a major tributary of the Ganga River, India. The Yamuna River runs through a major urban centre i.e. Delhi National Capital Region. The Yamuna River was divided into eight geomorphically distinct reaches on the basis of the assemblages of geomorphic units and the association of landscape, valley and floodplain settings. The morphological variability was analysed through stream power distribution and sediment load data at various stations. Stream power distribution of the Yamuna River basin is characterised by a non-linear pattern that was used to distinguish (a) high energy ‘natural' upstream reaches, (b) ‘anthropogenically altered', low energy middle stream reaches, and (c) ‘rejuvenated' downstream reaches again with higher stream power. The relationship between stream power and channel morphology in these reaches was integrated with sediment load data to define the maximum flow efficiency (MFE) as the threshold for geomorphic transition. This analysis supports the continuity of river processes and the significance of a holistic, basin-scale approach rather than isolated local scale analysis in river studies.

  14. We'll meet again: revealing distributional and temporal patterns of social contact.

    Directory of Open Access Journals (Sweden)

    Thorsten Pachur

    Full Text Available What are the dynamics and regularities underlying social contact, and how can contact with the people in one's social network be predicted? In order to characterize distributional and temporal patterns underlying contact probability, we asked 40 participants to keep a diary of their social contacts for 100 consecutive days. Using a memory framework previously used to study environmental regularities, we predicted that the probability of future contact would follow in systematic ways from the frequency, recency, and spacing of previous contact. The distribution of contact probability across the members of a person's social network was highly skewed, following an exponential function. As predicted, it emerged that future contact scaled linearly with frequency of past contact, proportionally to a power function with recency of past contact, and differentially according to the spacing of past contact. These relations emerged across different contact media and irrespective of whether the participant initiated or received contact. We discuss how the identification of these regularities might inspire more realistic analyses of behavior in social networks (e.g., attitude formation, cooperation.

  15. Flea species infesting dogs in Spain: updated spatial and seasonal distribution patterns.

    Science.gov (United States)

    Gálvez, R; Montoya, A; Checa, R; Martín, O; Marino, V; Miró, G

    2017-03-01

    This entomological survey examines the spatial and seasonal distribution patterns of flea species infesting dogs in Spain. Bioclimatic zones covering broad climate and vegetation ranges were surveyed according to size. In a cross-sectional spatial survey carried out from late May 2013 to mid-July 2015, 1084 dogs from 42 different locations were examined. A total of 3032 fleas were collected and identified as belonging to the following species: Ctenocephalides felis (Siphonaptera: Pulicidae) (81.7%, 2476 fleas); Ctenocephalides canis (11.4%, 347 fleas); Pulex irritans (Siphonaptera: Pulicidae) (6.9%, 208 fleas), and Echidnophaga gallinacea (Siphonaptera: Pulicidae) (0.03%, one flea). Variables observed to have effects on flea abundance were animal weight, sex, length of hair and habitat. In the seasonal survey conducted from June 2014 to June 2015, 1014 fleas were collected from 239 dogs at 30 veterinary practices across Spain. Peaks in C. felis abundance were observed in early summer and late autumn, whereas high numbers of P. irritans and C. canis were recorded in autumn. Numbers of fleas detected in winter were low overall. Based on these findings, the present study updates the spatial and seasonal distributions of flea species in Spain and assesses the impacts of host and habitat variables on flea infestation. © 2016 The Royal Entomological Society.

  16. Distributional patterns of shallow-water polychaetes in the Magellan region: a zoogeographical and ecological synopsis

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    Américo Montiel San Martín

    2005-12-01

    Full Text Available The zoogeography of polychaete annelids was described for the Magellan region. This work considered information available from 19 expeditions carried out in the last 124 years of polychaete taxonomic research around the southernmost tip of the South American continental shelf. The polychaete fauna of the Magellan region comprised a total of 431 species belonging to 108 genera and 41 families. MDS and ANOSIM analyses showed the Magellan region to be divided into two subregions, one on the Pacific side of the tip of South America and one on the Atlantic side. These subregions showed a low percentage of “endemic species” ( 70% of the species recorded for the whole Magellan region showed a wide distribution range, and there were especially high affinities with Antarctic and Subantarctic areas. We suggest that the opening of the Straits of Magellan created a new pathway for enhanced exchange of faunal elements between the Pacific and the Atlantic. Transport of larvae via easterly directed currents of the West Wind Drift plays an important role in current distribution patterns of polychaete fauna around the tip of South America.

  17. Pan-Arctic aerosol number size distributions: seasonality and transport patterns

    Science.gov (United States)

    Freud, Eyal; Krejci, Radovan; Tunved, Peter; Leaitch, Richard; Nguyen, Quynh T.; Massling, Andreas; Skov, Henrik; Barrie, Leonard

    2017-07-01

    The Arctic environment has an amplified response to global climatic change. It is sensitive to human activities that mostly take place elsewhere. For this study, a multi-year set of observed aerosol number size distributions in the diameter range of 10 to 500 nm from five sites around the Arctic Ocean (Alert, Villum Research Station - Station Nord, Zeppelin, Tiksi and Barrow) was assembled and analysed.A cluster analysis of the aerosol number size distributions revealed four distinct distributions. Together with Lagrangian air parcel back-trajectories, they were used to link the observed aerosol number size distributions with a variety of transport regimes. This analysis yields insight into aerosol dynamics, transport and removal processes, on both an intra- and an inter-monthly scale. For instance, the relative occurrence of aerosol number size distributions that indicate new particle formation (NPF) event is near zero during the dark months, increases gradually to ˜ 40 % from spring to summer, and then collapses in autumn. Also, the likelihood of Arctic haze aerosols is minimal in summer and peaks in April at all sites.The residence time of accumulation-mode particles in the Arctic troposphere is typically long enough to allow tracking them back to their source regions. Air flow that passes at low altitude over central Siberia and western Russia is associated with relatively high concentrations of accumulation-mode particles (Nacc) at all five sites - often above 150 cm-3. There are also indications of air descending into the Arctic boundary layer after transport from lower latitudes.The analysis of the back-trajectories together with the meteorological fields along them indicates that the main driver of the Arctic annual cycle of Nacc, on the larger scale, is when atmospheric transport covers the source regions for these particles in the 10-day period preceding the observations in the Arctic. The scavenging of these particles by precipitation is shown to be

  18. Pattern of distribution of serotonergic fibers to the amygdala and extended amygdala in the rat.

    Science.gov (United States)

    Linley, Stephanie B; Olucha-Bordonau, Francisco; Vertes, Robert P

    2017-01-01

    As is well recognized, serotonergic (5-HT) fibers distribute widely throughout the forebrain, including the amygdala. Although a few reports have examined the 5-HT innervation of select nuclei of the amygdala in the rat, no previous report has described overall 5-HT projections to the amygdala in the rat. Using immunostaining for the serotonin transporter, SERT, we describe the complete pattern of distribution of 5-HT fibers to the amygdala (proper) and to the extended amygdala in the rat. Based on its ontogenetic origins, the amygdala was subdivided into two major parts, pallial and subpallial components, with the pallial component further divided into superficial and deep nuclei (Olucha-Bordonau et al. 2015). SERT + fibers were shown to distributed moderately to densely to the deep and cortical pallial nuclei, but, by contrast, lightly to the subpallial nuclei. Specifically, 1) of the deep pallial nuclei, the lateral, basolateral, and basomedial nuclei contained a very dense concentration of 5-HT fibers; 2) of the cortical pallial nuclei, the anterior cortical and amygdala-cortical transition zone rostrally and the posteromedial and posterolateral nuclei caudally contained a moderate concentration of 5-HT fibers; and 3) of the subpallial nuclei, the anterior nuclei and the rostral part of the medial (Me) nuclei contained a moderate concentration of 5-HT fibers, whereas caudal regions of Me as well as the central nuclei and the intercalated nuclei contained a sparse/light concentration of 5-HT fibers. With regard to the extended amygdala (primarily the bed nucleus of stria terminalis; BST), on the whole, the BST contained moderate numbers of 5-HT fibers, spread fairly uniformly throughout BST. The findings are discussed with respect to a critical serotonergic influence on the amygdala, particularly on the basal complex, and on the extended amygdala in the control of states of fear and anxiety. J. Comp. Neurol. 525:116-139, 2017. © 2016 Wiley Periodicals, Inc.

  19. Patterns of distribution and landscape connectivity of the stag beetle in a human-dominated landscape

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    Francesca Della Rocca

    2017-07-01

    Full Text Available Urbanisation and the spread of agriculture have resulted in high levels of forest loss, habitat fragmentation and degradation in many regions of the world. In Italy, the Po Plain is the most human-dominated landscape of the country and, after decades of exploitation, old-growth forests have been reduced to small and isolated patches, often threatened by invasive tree species such as the black locust (Robinia pseudoacacia. In these habitats, the occurrence of many forest-dependent species is related to the quality and availability of suitable areas, as well as the connectivity between the remaining forested patches. Thus, recently developed species distribution models have been applied, namely the Ensemble of Small Models (ESMs, to identify areas of occurrence for a rare and protected saproxylic beetle species, the stag beetle Lucanus cervus and the inverse of the resulting distribution maps as resistance maps have been used to estimate landscape connectivity for this species. Response curves suggested that the probability of the stag beetle occurrence increased with habitat diversity, grassland coverage and native forests, especially oak and mixed forests. The other forest coverage, such as those with black locust, beech, chestnut and black cherry, showed a unimodal relationship peaking approximately at 70%, 8%, 55% and 13% respectively. The stag beetle occurrence was unimodal related to distance to watercourses and distance to human settlements and negatively related to shrub-lands, croplands, sparse and dense human settlements. Landscape connectivity showed similar patterns, except for oak forest coverage, which showed a negative relationship to landscape connectivity. In conclusion, stag beetles can persist in a human dominated landscape only in the presence of forest patches, including those with black locust trees. It is also inferred that ESMs may be suitable for modelling rare species distributions and estimating landscape connectivity to

  20. Pattern and Distribution of Colorectal Cancer in Tanzania: A Retrospective Chart Audit at Two National Hospitals

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    Leonard K. Katalambula

    2016-01-01

    Full Text Available Background. Colorectal cancer (CRC is a growing public health concern with increasing rates in countries with previously known low incidence. This study determined pattern and distribution of CRC in Tanzania and identified hot spots in case distribution. Methods. A retrospective chart audit reviewed hospital registers and patient files from two national institutions. Descriptive statistics, Chi square (χ2 tests, and regression analyses were employed and augmented by data visualization to display risk variable differences. Results. CRC cases increased sixfold in the last decade in Tanzania. There was a 1.5% decrease in incidences levels of rectal cancer and 2% increase for colon cancer every year from 2005 to 2015. Nearly half of patients listed Dar es Salaam as their primary residence. CRC was equally distributed between males (50.06% and females (49.94%, although gender likelihood of diagnosis type (i.e., rectal or colon was significantly different (P=0.027. More than 60% of patients were between 40 and 69 years. Conclusions. Age (P=0.0183 and time (P=0.004 but not gender (P=0.0864 were significantly associated with rectal cancer in a retrospective study in Tanzania. Gender (P=0.0405, age (P=0.0015, and time (P=0.0075 were all significantly associated with colon cancer in this study. This retrospective study found that colon cancer is more prevalent among males at a relatively younger age than rectal cancer. Further, our study showed that although more patients were diagnosed with rectal cancer, the trend has shown that colon cancer is increasing at a faster rate.

  1. A reverse taxonomic approach to assess macrofaunal distribution patterns in abyssal Pacific polymetallic nodule fields.

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    Annika Janssen

    Full Text Available Heightened interest in the exploitation of deep seafloor minerals is raising questions on the consequences for the resident fauna. Assessing species ranges and determination of processes underlying current species distributions are prerequisites to conservation planning and predicting faunal responses to changing environmental conditions. The abyssal central Pacific nodule belt, located between the Clarion and Clipperton Fracture Zones (CCZ, is an area prospected for mining of polymetallic nodules. We examined variations in genetic diversity and broad-scale connectivity of isopods and polychaetes across the CCZ. Faunal assemblages were studied from two mining claims (the eastern German and French license areas located 1300 km apart and influenced by different productivity regimes. Using a reverse taxonomy approach based on DNA barcoding, we tested to what extent distance and large-scale changes in environmental parameters lead to differentiation in two macrofaunal taxa exhibiting different functions and life-history patterns. A fragment of the mitochondrial gene Cytochrome Oxidase Subunit 1 (COI was analyzed. At a 97% threshold the molecular operational taxonomic units (MOTUs corresponded well to morphological species. Molecular analyses indicated high local and regional diversity mostly because of large numbers of singletons in the samples. Consequently, variation in composition of genotypic clusters between sites was exceedingly large partly due to paucity of deep-sea sampling and faunal patchiness. A higher proportion of wide-ranging species in polychaetes was contrasted with mostly restricted distributions in isopods. Remarkably, several cryptic lineages appeared to be sympatric and occurred in taxa with putatively good dispersal abilities, whereas some brooding lineages revealed broad distributions across the CCZ. Geographic distance could explain variation in faunal connectivity between regions and sites to some extent, while assumed

  2. Chemosymbiotic species from the Gulf of Cadiz (NE Atlantic: distribution, life styles and nutritional patterns

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    C. F. Rodrigues

    2013-04-01

    Full Text Available Previous work in the mud volcanoes from the Gulf of Cadiz (South Iberian Margin revealed a high number of chemosymbiotic species, namely bivalves and siboglinid polychaetes. In this study we give an overview of the distribution and life styles of these species in the Gulf of Cadiz, determine the role of autotrophic symbionts in the nutrition of selected species using stable isotope analyses (δ13C, δ15N and δ34S and investigate the intra-specific variation of isotope signatures within and between study sites. During our studies, we identified twenty siboglinidae and nine bivalve chemosymbiotic species living in fifteen mud volcanoes. Solemyid bivalves and tubeworms of the genus Siboglinum are widespread in the study area, whereas other species were found in a single mud volcano (e.g. "Bathymodiolus" mauritanicus or restricted to deeper mud volcanoes (e.g. Polybrachia sp., Lamelisabella denticulata. Species distribution suggests that different species may adjust their position within the sediment according to their particular needs, and to the intensity and variability of the chemical substrata supply. Tissue stable isotope signatures for selected species are in accordance with values found in other studies, with thiotrophy as the dominant nutritional pathway, and with methanotrophy and mixotrophy emerging as secondary strategies. The heterogeneity in terms of nutrient sources (expressed in the high variance of nitrogen and sulphur values and the ability to exploit different resources by the different species may explain the high diversity of chemosymbiotic species found in the Gulf of Cadiz. This study increases the knowledge on distributional patterns and resource partitioning of chemosymbiotic species and highlights how trophic fuelling varies on spatial scales with direct implications to seep assemblages and potentially to the biodiversity of continental margin.

  3. Intra-articular distribution pattern after ultrasound-guided injections in wrist joints of patients with rheumatoid arthritis

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    Boesen, Mikael [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark)], E-mail: parker@frh.regioh.dk; Jensen, Karl Erik [State Hospital, Department of Radiology, MRI Division, Copenhagen (Denmark)], E-mail: karl.erik.Jensen@rh.regionh.dk; Torp-Pedersen, Soren [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark); Cimmino, Marco A. [Rheumatologic Clinic, Department of Internal Medicine, University of Genoa (Italy)], E-mail: cimmino@unige.it; Danneskiold-Samsoe, Bente; Bliddal, Henning [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark)

    2009-02-15

    Objective: To investigate the distribution of an ultrasound-guided intra-articular (IA) injection in the wrist joint of patients with rheumatoid arthritis (RA). Methods: An ultrasound-guided IA drug injection into the wrist joint was performed in 17 patients with 1 ml methylprednisolone (40 mg/ml), 0.5 ml Lidocaine (5 mg/ml) and 0.15 ml gadolinium (Omniscan 0.5 mmol/ml). The drug solution was placed in the central proximal part of the wrist between the distal radius and the lunate bone. Coronal and axial MRI sequences were performed after the injection to visualize the distribution. Carpal distribution (radio-carpal, inter-carpal, and carpo-metacarpal) as well as radio-ulnar distribution was recorded. Full distribution in one compartment was given the value 1, partial distribution 0.5 and no distribution 0. A sum of the total distribution for all four compartments was calculated and correlated to the clinical parameters and the MRI OMERACT scores. Results: No uniform pattern was seen in the distribution of the contrast. Only two patients had full contrast distribution to all four compartments, and the mean distribution count for all patients was 2.4 (range 0.5-4). The distribution count correlated with the MRI OMERACT synovitis score (r = 0.60, p = 0.014), but not with the erosions, bonemarrow oedema scores or any clinical parameters. Conclusion: The distribution of contrast on MRI showed patient specific and random patterns after IA injections in active RA wrist joints. The degree of distribution increased with the MRI synovitis score, while no association was found with the erosion- and bonemarrow oedema score. These results indicate that a single injection into a standard injection site in the proximal part of the wrist cannot be assumed to distribute - and treat - the whole joint.

  4. Belo Horizonte em recortes

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    Ivete Lara Camargos Walty

    1998-03-01

    Full Text Available A partir do conceito de rizoma de Deleuze e Guatari, faz-se uma montagem de trechos de textos literários sobre Belo Horizonte, intercalados com extratos do livro As cidades invisíveis, de Italo Calvino, como objetivo de se esboçar faces/retratos da cidade.

  5. Horizontal violence in Nursing

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    Tsimoulaki Evangelia

    2017-01-01

    Full Text Available One’s effort to clarify the definition of horizontal labour violence is of great importance, due to the variety of definitions that are mentioned in the worldwide scientific literature. Furthermore, the reference of multiple forms of such violence herein the nurse professional group is challenging, as well. Another fact of great importance is that, any form of professional violence (horizontal violence, horizontal mobbing in the work place environment can be possibly escalated and include even physical abuse (Bullying, besides the psychological and emotional impact for the victim. The definitions of Horizontal violence, Mobbing and Bullying, include a repeated negative behaviour emanating from at least one “predator” towards at least one “victim”, with work status differences and the existence or lack of physical abuse (Bullying. Horizontal violence is a hostile, aggressive and harmful behaviour which is either overt or concealed and is pointed from an individual to another individual of the same working rank and causes intense emotional pain at the victim. The manifestations vary from humiliating tasks assignment or the victim’s efforts undermining to clearly aggressive behaviors (criticism, intimidation, sarcasm etc.. The reason behind this phenomenon is multifactorial extended not only towards the working environment but also to the personal characteristics of the “predator” as well as the possible “victim”. The researchers emphasize the high incidence of the phenomenon, as well as the cost that is induced by the violent behaviors to both the health professionals and the hospital. Finally, they point out the paradox of the presence of violence inside a system that is designed to promote health.

  6. Germline methylation patterns determine the distribution of recombination events in the dog genome.

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    Berglund, Jonas; Quilez, Javier; Arndt, Peter F; Webster, Matthew T

    2014-12-19

    The positive-regulatory domain containing nine gene, PRDM9, which strongly associates with the location of recombination events in several vertebrates, is inferred to be inactive in the dog genome. Here, we address several questions regarding the control of recombination and its influence on genome evolution in dogs. First, we address whether the association between CpG islands (CGIs) and recombination hotspots is generated by lack of methylation, GC-biased gene conversion (gBGC), or both. Using a genome-wide dog single nucleotide polymorphism data set and comparisons of the dog genome with related species, we show that recombination-associated CGIs have low CpG mutation rates, and that CpG mutation rate is negatively correlated with recombination rate genome wide, indicating that nonmethylation attracts the recombination machinery. We next use a neighbor-dependent model of nucleotide substitution to disentangle the effects of CpG mutability and gBGC and analyze the effects that loss of PRDM9 has on these rates. We infer that methylation patterns have been stable during canid genome evolution, but that dog CGIs have experienced a drastic increase in substitution rate due to gBGC, consistent with increased levels of recombination in these regions. We also show that gBGC is likely to have generated many new CGIs in the dog genome, but these mostly occur away from genes, whereas the number of CGIs in gene promoter regions has not increased greatly in recent evolutionary history. Recombination has a major impact on the distribution of CGIs that are detected in the dog genome due to the interaction between methylation and gBGC. The results indicate that germline methylation patterns are the main determinant of recombination rates in the absence of PRDM9. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  7. The advertisement call, color patterns and distribution of Ischnocnema izecksohni (Caramaschi and Kisteumacher, 1989 (Anura, Brachycephalidae

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    Pedro P. G. Taucce

    2012-01-01

    Full Text Available Ischnocnema izecksohni inhabits the gallery forests from the Quadrilátero Ferrífero, Southern Espinhaço range, state of Minas Gerais, southeastern Brazil, and it is considered endemic to this region. Its closest related species is I. nasuta according to the original description. We describe the advertisement call of I. izecksohni based on specimens recorded and collected at the municipality of Nova Lima, state of Minas Gerais, distant about 10 km straight line from its type locality. The advertisement call consists of a group of notes emitted sporadically without a regular interval between the calls. Call duration (n = 36 calls in four individuals ranged from 1.03 to 1.85 s (= 1.52 ± 0.21 s and the call rise time from 0.66 to 1.52 s (= 1.16 ± 0.25 s, with 34-57 notes per call (= 47.42 ± 6.03. Peak frequency ranged from 2250 to 2625 Hz, the dominant frequency from 1317.8 to 3128.0 Hz and interval between notes from 22.00 to 41.00 ms (= 28.63 ± 0.03 ms. From the examination of herpetological collections, morphological and bioacoustical data we extended the species known distribution ca. 200 km eastward, to ten new localities, all of them outside the Quadrilátero Ferrífero region, at the Mantiqueira mountain range. We analyzed color patterns and we find some dorsal patterns not described at the original description of I. izecksohni. We also make some comments concerning the taxonomic status of I. izecksohni and I. nasuta.

  8. The geographical pattern of distribution of the genus Tityobuthus Pocock, 1890, a typical Ananterinae element endemic to Madagascar (Scorpiones: Buthidae).

    Science.gov (United States)

    Lourenço, Wilson R; Waeber, Patrick O; Wilmé, Lucienne

    2016-01-01

    New comments are proposed for the Ananterinae (sensu Pocock) or the 'Ananteris Group'. The worldwide pattern of distribution of the elements associated with the Ananterinae, as well as aspects of their ecology, is discussed. The biogeographic patterns presented by extant and fossil elements of this group confirm not only the characteristics of a lineage representing a typical Gondwanian distribution, but correspond also to older Pangean patterns. One new species is described in the genus Tityobuthus Pocock. This new species is also a possible endemic element to the Island of Nosy-Be or at least to the Sambirano region. Generally, the Madagascar pattern of Tityobuthus is following the Neogrosphus rule, showing typical high species richness with low dispersal when the ancestral population had a large niche breadth. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  9. Pattern and distribution of colonic diverticulosis: analysis of 2877 barium enemas in Thailand.

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    Lohsiriwat, Varut; Suthikeeree, Wanwarang

    2013-12-14

    To determine the pattern and distribution of colonic diverticulosis in Thai adults. A review of the computerized radiology database for double contrast barium enema (DCBE) in Thai adults was performed at the Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand. Incomplete studies and DCBE examinations performed in non-Thai individuals were excluded. The pattern and distribution of colonic diverticulosis detected during DCBE studies from June 2009 to October 2011 were determined. The occurrence of solitary cecal diverticulum, rectal diverticulum and giant diverticulum were reported. Factors influencing the presence of colonic diverticulosis were evaluated. A total of 2877 suitable DCBE examinations were retrospectively reviewed. The mean age of patients was 59.8 ± 14.7 years. Of these patients, 1778 (61.8%) were female and 700 (24.3%) were asymptomatic. Colonic diverticulosis was identified in 820 patients (28.5%). Right-sided diverticulosis (641 cases; 22.3%) was more frequently reported than left-sided diverticulosis (383 cases; 13.3%). Pancolonic diverticulosis was found in 98 cases (3.4%). The occurrence of solitary cecal diverticulum, rectal diverticulum and giant diverticulum were 1.5% (42 cases), 0.4% (12 cases), and 0.03% (1 case), respectively. There was no significant difference in the overall occurrence of colonic diverticulosis between male and female patients (28.3% vs 28.6%, P = 0.85). DCBE examinations performed in patients with some gastrointestinal symptoms revealed the frequent occurrence of colonic diverticulosis compared with those performed in asymptomatic individuals (29.5% vs 25.3%, P = 0.03). Change in bowel habit was strongly associated with the presence of diverticulosis (a relative risk of 1.39; P = 0.005). The presence of diverticulosis was not correlated with age in symptomatic patients or asymptomatic individuals (P > 0.05). Colonic diverticulosis was identified in 28.5% of DCBE examinations in Thai adults. There

  10. Foliar Nutrient Distribution Patterns in Sympatric Maple Species Reflect Contrasting Sensitivity to Excess Manganese.

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    Denise R Fernando

    Full Text Available Sugar maple and red maple are closely-related co-occurring tree species significant to the North American forest biome. Plant abiotic stress effects including nutritional imbalance and manganese (Mn toxicity are well documented within this system, and are implicated in enhanced susceptibility to biotic stresses such as insect attack. Both tree species are known to overaccumulate foliar manganese (Mn when growing on unbuffered acidified soils, however, sugar maple is Mn-sensitive, while red maple is not. Currently there is no knowledge about the cellular sequestration of Mn and other nutrients in these two species. Here, electron-probe x-ray microanalysis was employed to examine cellular and sub-cellular deposition of excessively accumulated foliar Mn and other mineral nutrients in vivo. For both species, excess foliar Mn was deposited in symplastic cellular compartments. There were striking between-species differences in Mn, magnesium (Mg, sulphur (S and calcium (Ca distribution patterns. Unusually, Mn was highly co-localised with Mg in mesophyll cells of red maple only. The known sensitivity of sugar maple to excess Mn is likely linked to Mg deficiency in the leaf mesophyll. There was strong evidence that Mn toxicity in sugar maple is primarily a symplastic process. For each species, leaf-surface damage due to biotic stress including insect herbivory was compared between sites with acidified and non-acidified soils. Although it was greatest overall in red maple, there was no difference in biotic stress damage to red maple leaves between acidified and non-acidified soils. Sugar maple trees on buffered non-acidified soil were less damaged by biotic stress compared to those on unbuffered acidified soil, where they are also affected by Mn toxicity abiotic stress. This study concluded that foliar nutrient distribution in symplastic compartments is a determinant of Mn sensitivity, and that Mn stress hinders plant resistance to biotic stress.

  11. Distribution Pattern of Sweet Potato Whitefly Bemisia tabaci (Gennadius on Tomato Plants

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    K.M. Azam

    1997-01-01

    Full Text Available A field experiment was conducted to study the intra plant distribution and temporal dispersion patterns of whitetly (Bemisia tabaci Gennadius eggs and nymphs on tomato plants to establish a sampling method which would give accurate estimates of the population size. From the third week to the ninth week after transplanting, terminal leaflets were collected from the outer and inner canopies of each of the upper, middle, and lower plant strata. A strong ovipositional preference was found in whitefly adults at an early crop age. A maximum of 50.6% of the eggs were deposited in the middle stratum followed by upper (36. 15% and lower strata (13.3%. However, most of the nymphs (65.5% were present in the lower stratum followed by middle (32.4% and upper strata (2. l %. These findings indicated that when taking observations in egg counts the most preferred site is the upper and middle strata while for nymphal counts it is the lower and middle strata. There was a sharp decrease in egg and nymphal counts from the seventh week after transplantation which clearly indicated that, after this age , the corp is not preferred by whitefly . Egg and nymphal population of whitefly on tomato plants in the field were distributed in aggregates as evident by high variance to mean ratio. Values ranged from 2.72 to 14.36 and 4.52 to 21.82 for egg counts and nymphal population, respectively.  Aggregation of whitefly eggs and nymphs in all cases might be due to the behavior of adults to congregate and to the heterogeneity of the environment . The appropriate number of leaflets required for the estimation of egg density at 10% and 20% error was found to be 149 and 37, respectively. In the case of nymphal population the numbers were 163 and 41 at 10% and 20% error, respectively.

  12. [Interpretation of spatial distribution pattern for dissolved inorganic nitrogen concentration in coastal estuary using hyperspectral data].

    Science.gov (United States)

    Zhang, Dong; Xu, Yong; Zhang, Ying; Li, Huan

    2010-06-01

    Choosing dissolved inorganic nitrogen (DIN) as one of the representative nutritional salt monitoring indexes, a hyperspectral remotely sensed inversion model was built and applied to quantitatively retrieve water quality parameters with its spatial distribution patterns in coastal estuary with high suspended sediment concentration (SSC). It was found that when SSC was larger than 0.1 kg/m3, DIN concentration had a notable inverse correlation with SSC and the correlation coefficient R2 reached 0.617. Based on this conclusion, firstly the in-situ observed water surface remote sensing reflectance was resampled according to the spectral response characters of Hyperion sensor. And then, statistical correlation analysis between reflectance and DIN concentration was carried out. The results showed that band reflectance of R804 and R630 representing the second and first reflectance peak of water spectrum curve were sensitive to the variation of DIN concentration. And then, a pseudo remotely sensed sand parameter index R804 x R630/(R804 - R630) was calculated for the construction of the nonlinear DIN quantitative reversion model. Correlation coefficient R2 between observed and simulated DIN concentrations for 29 calibrating samples and 10 validating samples were 0.746 and 0.67, while their mean absolute errors reached 109.07 and 147.58 microg/L, respectively. The model was then applied on Hyperion hyperspectral image to get the spatial distribution character of DIN concentration in Sheyanghe river estuary and the DIN concentration was between 52 to 513 microg/L. Results indicated that in coastal estuary which was dominated by suspended sediments, the diffusive trends of DIN concentration reversed by remote sensing techniques had an intimate relationship with motions of tidal current and transportation attributes of SSC. As the hydrodynamic conditions were unclear, hyperspectral remote sensing technique was an effective technical way for dynamic survey of DIN concentration.

  13. Tissue-specific expression pattern and histological distribution of NLRP3 in Chinese yellow chicken.

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    Ye, Jinhui; Yu, Meng; Zhang, Kaizhao; Liu, Jianxin; Wang, Qingnan; Tao, Pan; Jia, Kun; Liao, Ming; Ning, Zhangyong

    2015-09-01

    Pathogen-associated molecular patterns (PAMPs) play important role in inflammation which means response of the host to stimuli. NOD-like receptor protein 3 (NLRP3) inflammasome is involved in the onset and development of inflammation. NLRP3, as one of the most important inflammasome sensors, has significant effect on the regulation of inflammasome activation to avoid the consequences of over activation. Up to date, there are no detailed tissue specific expression and distribution data about NLPR3 in chicken. Here, NLRP3 of Chinese yellow chicken was cloned and sequence analyzed, the polyclonal antibody was produced by purified protein of recombinant prokaryotic expression. Relative expression levels and tissue distribution of NLRP3 were investigated by real-time quantitative PCR and immunohistochemical analysis, respectively. The results showed that NLRP3 gene is highly variable between mammalian and avian. The nucleotide homology of NLRP3 between yellow chicken and Bos taurus, Hainan black goat, Sus scrofa, Callithrix jacchus, Homo sapiens, Macaca mulatta, Mus musculus and Rattus norvegicus were 54.2%, 53.9%, 53.7%, 55.4%, 54.3%, 54.5%, 53.5% and 53.7%. NLRP3 expressed in all detected tissues and higher in the trachea are lung than in other tissues. Cytoplasmic expression of NLRP3 was detected in ciliated epithelial cells, basal cells and cells in lamina propria of trachea, alveolar epithelial cells, cardiac muscle cells, cerebral cortex neurons, epithelial reticular cells of the spleen, and lymphocytes of medulla in stannius follicle, liver cells and the renal tubule epithelial cells. The results will help to elucidate the role of NLRP3 of different tissues in inflammatory diseases of chicken and provide a basis for further investigations in the function and evolution of NLRP3 in different species, which would be helpful for further research on avian inflammatory diseases.

  14. [Population structure and spatial distribution pattern of Camellia azalea in E' huangzhang Nature Reserve of Guangdong, China].

    Science.gov (United States)

    Li, Xin-lei; Sun, Zhen-yuan; Li, Ji-yuan; Xu, Yi; Luo, Jian

    2013-08-01

    This paper studied the structures of basal diameter, height and canopy width of Camellia azalea population in E' huangzhang Nature Reserve of Guangdong. The spatial distribution patterns and dynamics of the population were measured by applying aggregate indices including disperse coefficient, negative binomial distribution, Cassie index, clumping index, mean crowding, patch index and Green index. The results showed that in the natural distribution region, the population was mainly composed of adult trees, and was in declining due to seriously lack of seedlings. The structures of diameter, height and canopy width were not identical among different plots. In the plots, the spatial distribution pattern of C. azalea population showed clump or random, and changed from clump to random with the development of the population.

  15. Horizontal gene transfer in chromalveolates

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    Bhattacharya Debashish

    2007-09-01

    Full Text Available Abstract Background Horizontal gene transfer (HGT, the non-genealogical transfer of genetic material between different organisms, is considered a potentially important mechanism of genome evolution in eukaryotes. Using phylogenomic analyses of expressed sequence tag (EST data generated from a clonal cell line of a free living dinoflagellate alga Karenia brevis, we investigated the impact of HGT on genome evolution in unicellular chromalveolate protists. Results We identified 16 proteins that have originated in chromalveolates through ancient HGTs before the divergence of the genera Karenia and Karlodinium and one protein that was derived through a more recent HGT. Detailed analysis of the phylogeny and distribution of identified proteins demonstrates that eight have resulted from independent HGTs in several eukaryotic lineages. Conclusion Recurring intra- and interdomain gene exchange provides an important source of genetic novelty not only in parasitic taxa as previously demonstrated but as we show here, also in free-living protists. Investigating the tempo and mode of evolution of horizontally transferred genes in protists will therefore advance our understanding of mechanisms of adaptation in eukaryotes.

  16. Thermal Contraction Crack Polygon Classification and Distribution: Morphological Variations in Northern Hemisphere Patterned Ground

    Science.gov (United States)

    Levy, J.; Head, J.; Marchant, D.

    2008-09-01

    provides context for interpretation of contraction crack polygons at the NASA Phoenix landing site. Survey Parameters We present an updated survey of 413 HiRISE images of the martian northern hemisphere (30-80°N), at resolutions of ~30 cm/pixel, spanning primary science phase orbits 001331 to 007492 [18]. Of the surveyed images, 276 contain polygonally patterned ground (69%). Polygon diameters were measured using centre-to-centre point distance measurements between adjacent polygons, and were averaged across the four nearest-neighbour points to give a representative diameter. Polygon Classification and Distribution We divide polygons into 8 morphological types (Figure 1). Commonly more than one type is present in a single HiRISE image, suggesting variability in polygon-forming substrate conditions on 100 m to km length scales [19]. Polygon types are strongly grouped by latitude, transitioning from one to the next across the studied latitude range. High Relief (HR). Initially described by [16], HR polygons are well-formed and have strong contrasts between polygon centres and depressed polygon margin troughs. HR are morphologically similar to S1 terrain described by [3], averaging ~6 m in diameter (N = 160). HR polygon distribution is centred at 69.4°N. Northern Plains (NP1-3). Northern plains polygons are the predominant northern hemisphere polygon species (196 occurrences). NP are present in the vicinity of the Phoenix lander [16], and occur in three varieties: NP1, consisting of well-formed, low-troughed polygons present on boulder-topped mounds (mean diameter ~5 m, N = 138); NP2, consisting of less-sharply defined polygons, present on both smooth, and gently hummocked surfaces (mean diameter ~5 m, N = 121); and NP3, which are poorly polygonalized features, commonly consisting of long, sinuous cracks which form coarse networks (mean diameter ~6 m, N = 147). Polygons at the Phoenix lander site appear to be NP2/NP3. NP polygons are all broadly similar to the S group

  17. Species distribution and antifungal susceptibility pattern of Candida causing oral candidiasis among hospitalized patients

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    Faseela Taivalap Shafi

    2015-01-01

    Full Text Available Background: Oral candidiasis is increasingly seen among hospitalized patients and is usually treated empirically. It can be the marker of systemic infection. Antifingal resistance is one of the emerging problems in candidiasis. Aim and Objectives: To study the distribution pattern of various Candida species among hospitalised patients with oral candidiasis, to detect the antifungal resistance among Candida and to assess the possible risk factors associated with those patients. Methods: Out of 300 patients screened, oral thrush material was collected from 36 patients having oral candidiasis. Candida spp. were isolated and identified. Antifungal susceptibility test was performed by disk diffusion method. Results: Candida albicans was the most frequently isolated species (64%. Highest resistance was seen with ketoconazole (18%. Except one C. tropicalis, all the isolates were sensitive to amphotericin B. All the patients were on broad spectrum antibiotic treatment. Diabetes mellitus was seen in 50 % of the patients. Other predisposing factors include tuberculosis, COPD, cancer and steroid treatment. Conclusion: Eventhough there is progressive shift from a predominance of C. albicans to non-albicans Candida species in candidiasis, C. albicans remains as the most important pathogen in oral candidiasis. Since azole resistance is increasing, accurate identification of Candida spp. and antifungal susceptibility testing is crucial for patient management and for facilitating hospital control measures.

  18. Patterns of Glycoconjugate Distribution during Molar Tooth Germ Development in Mice

    Directory of Open Access Journals (Sweden)

    AR. Varasteh

    2007-09-01

    Full Text Available Objective: The aim of the present study was to evaluate the structure and distribution of Glycoconjugates during molar tooth germ development in mice.Materials and Methods: Sixteen tooth germs were obtained from BALB/c mice embryos 15 to 18 days post-gestation and fixed in 10% formalin. After routine tissue processing, 5μm sections were cut and stained with BSA1-B4 and PNA using the lectin histochemical method. All slides were evaluated by light microscopy.Results: Both lectins showed positive reaction in the tooth germ but with spatiotemporal differences. During bell stage, the reaction was strong with BSA1-B4 but moderate with PNA. Strong PNA uptake was observed in the odontoblastic and ameloblastic nuclei alongwith the apical cytoplasm of the ameloblasts.Conclusion: Although the lectins that were used in the present study recognize the same terminal sugar residue, they reacted with different disaccharide sequences with various penaltomer sugars. Therefore it may be assumed that the pattern of affinity for different parts of the developing tooth germ such as ameloblasts and odontoblasts is different in various lectins.

  19. Distribution patterns suggest biomagnification of halogenated 1'-methyl-1,2'-bipyrroles (MBPs).

    Science.gov (United States)

    Pangallo, Kristin C; Reddy, Christopher M

    2009-01-01

    The halogenated 1'-methyl-1,2'-bipyrroles (MBPs) are a suite of marine natural products that have been detected in marine mammals worldwide. Although their concentrations are similar to persistent organic pollutants that biomagnify, such as 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), it is notyet clearthat these natural products also biomagnify. Here we analyze MBPs and CB-153 isolated from the blubber and liver of marine mammals stranded on the eastern coast of Massachusetts. Four odontocete species (Delphinus delphis, Lagenorhynchus acutus, Phocoena phocoena, and Globicephala melas) and two pinniped species (Halichoerus grypus and Phoca groenlandica) were sampled. MBPs were present in all odontocetes, but not detected in pinnipeds; CB-153 was detected in every species. MBP patterns indicative of biomagnification were found, including age-dependent concentration increases and reduced concentrations in adult females. Also explored were the similarities and differences with CB-153, the effects of nutritional state on contaminant distribution, and the maternal transfer of blubber-based organic contaminants.

  20. Evidences Dependent Population Distribution Patterns of Tiger and Leopard in Similipal Tiger Reserve, Odisha, India

    Directory of Open Access Journals (Sweden)

    Sandeep Ranjan Mishra

    2015-10-01

    Full Text Available The Tiger (Panthera tigris is an endangered carnivore with uncertain demographic status spanning 13 Asian countries. Due to its larger body size and carnivorous diet in nature it always occurs at low population densities. Further prey depletion due to overhunting (Karanth & Stith, 1998, poaching, habitat shrinkage (Kenny et al., 1995, Wcs, 1995 and direct killing altogether have also become a major factor for depletion of wild tiger populations tiger. Monitoring the abundance and its alteration is always important for the effective management of endangered species. Tiger is categorized as “Endangered” on the IUCN Red List (IUCN, 2008 and listed under Schedule-I of Wildlife (Protection Act, 1972 in India and Appendix-I of the CITES. Leopard (Panthera pardus is also included in the Schedule- I of the Indian Wildlife Protection Act, 1972 and is placed under “Least Concern” category of 2002 IUCN Red List of threatened animals. Similipal Tiger Reserve is one of the largest Tiger Reserves of India with an area of 2750 km2. Therefore we have to depend mainly on the direct sightings and evidence records of the animals to analysis the status and distribution pattern of these two big cats in the core area of this Tiger Reserve.

  1. Limnocythere (Ostracoda) distribution pattern in the Southern Ethiopian Rift during the Late Pleistocene and Holocene

    Science.gov (United States)

    Viehberg, Finn; Gebru, Tsige; Foerster, Verena; Schaebitz, Frank; Wagner, Bernd

    2014-05-01

    Sediment records from two lakes in the biodiversity hotspot of the Southern Ethiopian Rift were retrieved, Lake Chamo (c. 9 ka) and Chew Bahir (c. 45 ka). Sedimentological and palaeoecological proxies infer rapidly changing environmental conditions (wet-dry cycle) such as the African Humid Period. The fossil record in both archives is fairly rich in ostracode taxa throughout the cores and especially diverse in the genus Limnocythere. Here, we discuss the temporal and spatial distribution pattern of Limnocythere species in the Omo-Turkana basin in the context of palaeolimnological changes. In addition, we mapped extensively valve characteristics of the L. species to document morphological intraspecific variation also as a supplementary measure of environmental change. Our preliminary results show that regional biogeographical boundaries might have changed as a consequence, too. For instance, members of the Limnocythere thomasi -group (sensu Martens 1990) occur in our fossil record. In modern studies this species cluster is regarded as endemic fauna of Lakes Zway, Langano and Shala, which are associated with the freshwater ecoregion of the Northern Eastern Rift.

  2. A tale of two genomes: contrasting patterns of phylogeographic structure in a widely distributed bat.

    Science.gov (United States)

    Turmelle, Amy S; Kunz, Thomas H; Sorenson, Michael D

    2011-01-01

    One of the most widely distributed bats in the New World, the big brown bat (Eptesicus fuscus) exhibits well-documented geographic variation in morphology and life history traits, suggesting the potential for significant phylogeographic structure as well as adaptive differentiation among populations. In a pattern broadly consistent with morphologically defined subspecies, we found deeply divergent mitochondrial lineages restricted to different geographic regions. In contrast, sequence data from two nuclear loci suggest a general lack of regional genetic structure except for peripheral populations in the Caribbean and Mexico/South America. Coalescent analyses suggest that the striking difference in population structure between genomes cannot be attributed solely to different rates of lineage sorting, but is likely due to male-mediated gene flow homogenizing nuclear genetic diversity across most of the continental range. Despite this ongoing gene flow, selection has apparently been effective in producing and maintaining adaptive differentiation among populations, while strong female site fidelity, maintained over the course of millions of years, has produced remarkably deep divergence among geographically isolated matrilines. Our results highlight the importance of evaluating multiple genetic markers for a more complete understanding of population structure and history. © 2010 Blackwell Publishing Ltd.

  3. Habitat Preferences, Distribution Pattern, and Root Weight Estimation of Pasak Bumi (Eurycoma longifolia Jack.

    Directory of Open Access Journals (Sweden)

    Siti Masitoh Kartikawati

    2014-04-01

    Full Text Available Pasak bumi (Eurycoma longifolia Jack is one of non timber forest products with “indeterminate” conservation status and commercially traded in West Kalimantan. The research objective was to determine the potential of pasak bumi root per hectare and its ecological condition under natural habitat. Root weight of E. longifolia Jack was estimated using simple linear regression and exponential equation with stem diameter and height as independent variables. The results showed that the individual number of the population was 114 with the majority in seedling stage with 71 individuals (62.28%. The distribution was found in clumped pattern. Conditions of the habitat could be described as follows: daily average temperature of 25.6oC, daily average relative humidity of 73.6%, light intensity of 0.9 klx, and red-yellow podsolic soil with texture ranged from clay to sandy clay. The selected estimator model for E. longifolia Jack root weight used exponential equation with stem height as independent variable using the equation of Y= 21.99T0,010 and determination coefficient of 0.97. After height variable was added, the potential of E. longifolia Jack minimum root weight that could be harvested per hectare was 0.33 kg.

  4. Spatial Distribution and Temporal Patterns of Cassin?s Auklet Foraging and Their Euphausiid Prey in a Variable Ocean Environment

    OpenAIRE

    Suzanne Manugian; Elliott, Meredith L.; Russ Bradley; Julie Howar; Nina Karnovsky; Benjamin Saenz; Anna Studwell; Pete Warzybok; Nadav Nur; Jaime Jahncke

    2015-01-01

    Krill (Euphausiids) play a vital ecosystem role in many of the world's most productive marine regions, providing an important trophic linkage. We introduce a robust modeling approach to link Cassin's auklet (Ptychoramphus aleuticus) abundance and distribution to large-scale and local oceanic and atmospheric conditions and relate these patterns to similarly modeled distributions of an important prey resource, krill. We carried out at-sea strip transect bird surveys and hydroacoustic assessment...

  5. Pan-Arctic aerosol number size distributions: seasonality and transport patterns

    Directory of Open Access Journals (Sweden)

    E. Freud

    2017-07-01

    Full Text Available The Arctic environment has an amplified response to global climatic change. It is sensitive to human activities that mostly take place elsewhere. For this study, a multi-year set of observed aerosol number size distributions in the diameter range of 10 to 500 nm from five sites around the Arctic Ocean (Alert, Villum Research Station – Station Nord, Zeppelin, Tiksi and Barrow was assembled and analysed.A cluster analysis of the aerosol number size distributions revealed four distinct distributions. Together with Lagrangian air parcel back-trajectories, they were used to link the observed aerosol number size distributions with a variety of transport regimes. This analysis yields insight into aerosol dynamics, transport and removal processes, on both an intra- and an inter-monthly scale. For instance, the relative occurrence of aerosol number size distributions that indicate new particle formation (NPF event is near zero during the dark months, increases gradually to  ∼ 40 % from spring to summer, and then collapses in autumn. Also, the likelihood of Arctic haze aerosols is minimal in summer and peaks in April at all sites.The residence time of accumulation-mode particles in the Arctic troposphere is typically long enough to allow tracking them back to their source regions. Air flow that passes at low altitude over central Siberia and western Russia is associated with relatively high concentrations of accumulation-mode particles (Nacc at all five sites – often above 150 cm−3. There are also indications of air descending into the Arctic boundary layer after transport from lower latitudes.The analysis of the back-trajectories together with the meteorological fields along them indicates that the main driver of the Arctic annual cycle of Nacc, on the larger scale, is when atmospheric transport covers the source regions for these particles in the 10-day period preceding the observations in the Arctic. The scavenging of these particles

  6. An analysis of the phylogenetic distribution of the pea pathogenicity genes of Nectria haematococca MPVI supports the hypothesis of their origin by horizontal transfer and uncovers a potentially new pathogen of garden pea: Neocosmospora boniensis.

    Science.gov (United States)

    Temporini, Esteban D; VanEtten, Hans D

    2004-07-01

    The filamentous fungus Nectria haematococca mating population VI (MPVI) contains a cluster of genes required to cause disease on pea. This cluster of pea pathogenicity genes (the PEP cluster) is located on a supernumerary chromosome that is dispensable for normal growth in culture. The genes in the PEP cluster have a different G+C content and codon usage compared with the genes located on the other chromosomes and a non-homogeneous distribution within the species. These features suggest that the PEP cluster may have been acquired by N. haematococca MPVI through horizontal gene transfer (HGT). In this work, we show that homologues of the PEP genes are present in another pea pathogen, Fusarium oxysporum f. sp. pisi, but are not common among fungi that are phylogenetically closely related to N. haematococca MPVI. This phylogenetic discontinuity supports the hypothesis that the PEP cluster originated by HGT. Our analysis has also determined that homologues for all the PEP genes are present in Neocosmospora boniensis. A molecular characterization of the PEP homologues in this fungus shows that they are organized as a cluster, which has a different physical organization from the PEP cluster in N. haematococca. In addition, although no reports have been found to show that N. boniensis is a naturally occurring pea pathogen, we show here that this species is able to cause disease on pea.

  7. Distribuição temporal e espacial da leishmaniose visceral em humanos e cães em Belo Horizonte-MG, 1993 a 2007 Temporal and spatial distribution of leishmaniasis in humans and dogs from Belo Horizonte-MG, 1993-2007

    Directory of Open Access Journals (Sweden)

    E.G.P. Lopes

    2010-10-01

    Full Text Available O objetivo desta pesquisa foi descrever as análises da série cronológica e determinar a tendência da leishmaniose visceral em humanos e cães para o município de Belo Horizonte, de 1993 a 2007. De 1994, quando surgiram os primeiros casos da doença, até 2007, foram registrados 994 casos humanos autóctones com 116 óbitos. De 1993 a 2007, foram analisadas 1.492.401 amostras de sangue canino com percentual de positividade de 5,9%, utilizando-se os testes de enzyme-linked immunosorbent assay (ELISA como triagem e de imunofluorescência indireta (IFI como confirmatório. As análises indicaram que a leishmaniose visceral apresentou tendência crescente dos coeficientes de incidência em humanos e de prevalência em cães, e observaram-se arquétipos distintos dessa tendência, retratando o momento histórico de transição endêmica. A leishmaniose visceral em cães não apresentou características de distribuição sazonal, e não foi possível concluir a existência ou não de ciclicidade do fenômeno. A leishmaniose visceral em humanos e cães tem ampla distribuição espacial nas nove regionais administrativas com risco diferenciado de acometimento da doença, apesar da presença das fontes de infecção e dos susceptíveis em todo o município.The chronological series analysis and the tendencies of both human and canine visceral leishmaniasis were determined in Belo Horizonte city, from 1993 to 2007. From 1994, when the first cases of the disease were reported, until 2007, 994 human cases were recorded, which led to 116 deaths. From 1993 to 2007, 1,492,401 samples of canine blood were analyzed by the enzyme-linked immunosorbent assay (ELISA as screening test and by the Indirect Immunofluorescence (IFI as confirmatory test. The rate of positive results was 5.9%. The analyses indicated that the visceral leishmaniasis presents a tendency of increasing the coefficient of incidence in humans and prevalence in dogs and different archetypes of

  8. Influence of oceanographic fronts and low oxygen on the distribution ...

    African Journals Online (AJOL)

    The horizontal and vertical distributions of eggs and larvae of sardine Sardinops sagax, anchovy Engraulis encrasicolus and horse mackerel Trachurus trachurus capensis were examined in relation to distribution patterns of temperature, salinity and dissolved oxygen. Samples were collected during February–March 2002 ...

  9. Horizontal drilling activity in Manitoba

    Energy Technology Data Exchange (ETDEWEB)

    Fox, J.

    1997-04-01

    An update of horizontal well drilling in Manitoba was provided. Manitoba`s productive formations are: (1) the Bakken Formation, (2) the Lodgepole Formation, (3) the Mission Canyon Formation, (4) the Amaranth Formation, and (5) the Melita Formation. A total of 28 exploratory wells and 29 development wells, including 11 horizontal wells were drilled in 1996. The 11 horizontal wells accounted for 30 per cent of the drilling meterage. The leading drillers for horizontal wells in Manitoba are Tundra Oil and Gas, Chevron, Anderson and HCO. Production from horizontal wells in 1996 totaled 310 cubic meter per day. To date, no horizontal wells have been drilled in the Bakken Formation. The least successful horizontal well application has been in the Lodgepole Formation. A summary of horizontal well production was provided for each Formation. 4 tabs., 10 figs.

  10. Acacia trees pattern distribution as an indicator for changes in flow spatial distributions in a hyper-arid environment

    Science.gov (United States)

    Isaacson, Sivan; Ephrath, Jhonathan E.; Rachmilevitch, Shimon; Maman, Shimrit; Blumberg, Dan G.

    2017-04-01

    Arid regions are characterized by high spatial and temporal variability of precipitation, resulting in high spatial and temporal variation of vegetation cover. Because of low rainfall, the acacia trees in southern Israel are usually restricted to ephemeral stream (Wadi) beds, which possess higher soil moisture content than the surrounding landscape. Spatial analyses of tree distribution at the drainage basin scale contributes to a better understanding of the geo-hydrologic regime because water is the main limiting factor in such areas. That is, the spatial distribution of trees and their characteristics within the Wadi may reflect the spatial variance of water availability within different segments of the Wadi. The main objective of this study was to use the spatial distribution of different parameters of acacia trees as an indicator of past and present hydrological regimes within different segments of the Wadi. Tree size distribution was used as an indicator of long-term (decades) geo-hydrologic spatial processes affecting the acacia population. The tree health (NDVI) distribution was used as an indicator of short-term (months to a few years) geo-hydrologic spatial processes, such as the paths of recent flashfloods events. The distribution of the trees in the Wadi (ephemeral river) was divided into three distinct categories: (1) large trees with high NDVI values, (2) large trees with low NDVI values and (3) small trees with medium NDVI values. Using the resulting classification, we divided the Wadi into three sections, each representing a unique combination of long- and short-term geo-hydrologic processes affecting the acacia trees. We suggest that the lack of spatial correlation between tree size and health status is a result of spatio-temporal changes in the water supply. Our main conclusion is that past and current alterations of the runoff path can be detected by the spatial analysis of trees in hyper-arid regions

  11. Sleep-wake distribution and circadian patterns of epileptic seizures in children.

    Science.gov (United States)

    Gurkas, Esra; Serdaroglu, Ayse; Hirfanoglu, Tugba; Kartal, Ayse; Yılmaz, Unsal; Bilir, Erhan

    2016-07-01

    Epilepsy is one of the most common chronic neurologic disorders. Daily periodicity of epileptic seizures has been known for over a century. The diurnal patterns of epileptic seizures have also been observed in studies. To investigate the sleep/wake cycle, day/night, and 24-h periodicity of various seizure subtypes and seizure onset localizations in children. We analyzed the clinical seizures of 170 consecutive epilepsy patients who underwent video-electroencephalography (EEG) monitoring over the last 5 years. Semiology of the seizures was classified according to the semiological seizure classification. Origin of the seizures was defined by the onset of ictal activity on EEG. Seizures were evaluated in terms of occurrence during the day (06:00-18:00 h) or night (18:00-06:00 h), in wakefulness or in sleep, and within a 3-h time interval throughout 24 h. A total of 909 seizures were analyzed. Auras, dialeptic, myoclonic, hypomotor, atonic seizures, and epileptic spasms occurred more frequently in wakefulness; tonic, clonic, and hypermotor seizures occurred more frequently in sleep. Auras, dialeptic, and atonic seizures and epileptic spasms occurred more often during daytime; hypermotor seizures occurred more often at night. Generalized seizures were seen most frequently in wakefulness (between 12:00 and 18:00 h); frontal lobe seizures were seen at night and in sleep (between 24:00 and 03:00 h); temporal lobe seizures were seen in wakefulness (between 06:00 and 09:00 h and between 12:00 and 15:00 h); occipital seizures were seen during daytime and in wakefulness (between 09:00 and 12:00 h and between 15:00 and 18:00 h, respectively); parietal seizures were seen mostly during daytime. Seizures in children occur in specific circadian patterns and in specific sleep/wake distributions depending on seizure onset location and semiology. Copyright © 2016 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

  12. Patterns of biomass and carbon distribution across a chronosequence of Chinese pine (Pinus tabulaeformis forests.

    Directory of Open Access Journals (Sweden)

    Jinlong Zhao

    Full Text Available Patterns of biomass and carbon (C storage distribution across Chinese pine (Pinus tabulaeformis natural secondary forests are poorly documented. The objectives of this study were to examine the biomass and C pools of the major ecosystem components in a replicated age sequence of P. tabulaeformis secondary forest stands in Northern China. Within each stand, biomass of above- and belowground tree, understory (shrub and herb, and forest floor were determined from plot-level investigation and destructive sampling. Allometric equations using the diameter at breast height (DBH were developed to quantify plant biomass. C stocks in the tree and understory biomass, forest floor, and mineral soil (0-100 cm were estimated by analyzing the C concentration of each component. The results showed that the tree biomass of P. tabulaeformis stands was ranged from 123.8 Mg·ha-1 for the young stand to 344.8 Mg·ha-1 for the mature stand. The understory biomass ranged from 1.8 Mg·ha-1 in the middle-aged stand to 3.5 Mg·ha-1 in the young stand. Forest floor biomass increased steady with stand age, ranging from 14.9 to 23.0 Mg·ha-1. The highest mean C concentration across the chronosequence was found in tree branch while the lowest mean C concentration was found in forest floor. The observed C stock of the aboveground tree, shrub, forest floor, and mineral soil increased with increasing stand age, whereas the herb C stock showed a decreasing trend with a sigmoid pattern. The C stock of forest ecosystem in young, middle-aged, immature, and mature stands were 178.1, 236.3, 297.7, and 359.8 Mg C ha-1, respectively, greater than those under similar aged P. tabulaeformis forests in China. These results are likely to be integrated into further forest management plans and generalized in other contexts to evaluate C stocks at the regional scale.

  13. Patterns of Biomass and Carbon Distribution across a Chronosequence of Chinese Pine (Pinus tabulaeformis) Forests

    Science.gov (United States)

    Wang, Luoxin; Yu, Xiaowen; Zhao, Weihong; Song, Xiaoshuai; Zhang, Yanlei; Chen, Feng; Sun, Yu; He, Tengfei; Han, Hairong

    2014-01-01

    Patterns of biomass and carbon (C) storage distribution across Chinese pine (Pinus tabulaeformis) natural secondary forests are poorly documented. The objectives of this study were to examine the biomass and C pools of the major ecosystem components in a replicated age sequence of P. tabulaeformis secondary forest stands in Northern China. Within each stand, biomass of above- and belowground tree, understory (shrub and herb), and forest floor were determined from plot-level investigation and destructive sampling. Allometric equations using the diameter at breast height (DBH) were developed to quantify plant biomass. C stocks in the tree and understory biomass, forest floor, and mineral soil (0–100 cm) were estimated by analyzing the C concentration of each component. The results showed that the tree biomass of P. tabulaeformis stands was ranged from 123.8 Mg·ha–1 for the young stand to 344.8 Mg·ha–1 for the mature stand. The understory biomass ranged from 1.8 Mg·ha–1 in the middle-aged stand to 3.5 Mg·ha–1 in the young stand. Forest floor biomass increased steady with stand age, ranging from 14.9 to 23.0 Mg·ha–1. The highest mean C concentration across the chronosequence was found in tree branch while the lowest mean C concentration was found in forest floor. The observed C stock of the aboveground tree, shrub, forest floor, and mineral soil increased with increasing stand age, whereas the herb C stock showed a decreasing trend with a sigmoid pattern. The C stock of forest ecosystem in young, middle-aged, immature, and mature stands were 178.1, 236.3, 297.7, and 359.8 Mg C ha–1, respectively, greater than those under similar aged P. tabulaeformis forests in China. These results are likely to be integrated into further forest management plans and generalized in other contexts to evaluate C stocks at the regional scale. PMID:24736660

  14. Wave-like distribution patterns of Gfp-marked Pseudomonas fluorescens along roots of wheat plants grown in two soils

    NARCIS (Netherlands)

    Bruggen, van A.H.C.; Semenov, A.M.; Zelenev, V.V.; Semenov, A.V.; Raaijmakers, J.M.; Sayler, R.J.; Vos, de O.J.

    2008-01-01

    Culturable rhizosphere bacterial communities had been shown to exhibit wave-like distribution patterns along wheat roots. In the current work we show, for the first time, significant wave-like oscillations of an individual bacterial strain, the biocontrol agent Pseudomonas fluorescens 32 marked with

  15. Spatial and depth-associated distribution patterns of shallow gorgonians in the Algarve coast (Portugal, NE Atlantic)

    Science.gov (United States)

    Cúrdia, João; Monteiro, Pedro; Afonso, Carlos M. L.; Santos, Miguel N.; Cunha, Marina R.; Gonçalves, Jorge M. S.

    2013-09-01

    The ecological role of gorgonians for marine rocky bottoms is worldwide recognized, but the information on the distribution patterns of NE Atlantic temperate species is insufficient, considering current global, regional and local threats. To overcome the lack of information on the spatial distribution patterns of gorgonians in south Portugal, in 2009/2010, the occurrence and abundance of gorgonian species in rocky bottoms were quantified over more than 25 km of coast (37.1°N/8.6°W) down to 30 m depth. Eunicella labiata, Eunicella gazella, Eunicella verrucosa and Leptogorgia sarmentosa were abundant and frequent in the studied area, while Leptogorgia lusitanica was less abundant. All species evidenced a similar depth pattern, that is abundance significantly increased with depth below 15 m. At shallower waters (up to 15 m), the distribution of gorgonians may be constrained by abiotic factors and competition with algae. Indeed, the abundance of gorgonians was negatively correlated with the percentage cover of algae along the depth gradient, but gorgonians and sponges coexist. Competition among gorgonian species also seems to be low in this area because of the similarity in the abundance pattern observed for the most abundant species and also their high association. In NE Atlantic shallow temperate rocky bottoms, the distribution of gorgonians seems to be influenced by environmental factors and biological interactions, namely competition (algae) and coexistence (sponges and other gorgonians).

  16. Bipolar Plasma Membrane Distribution of Phosphoinositides and Their Requirement for Auxin-Mediated Cell Polarity and Patterning in Arabidopsis

    NARCIS (Netherlands)

    Tejos, R.; Sauer, M.; Vanneste, S.; Palacios-Gomez, M.; Li, H.; Heilmann, M.; van Wijk, R.; Vermeer, J.E.M.; Heilmann, I.; Munnik, T.; Friml, J.

    2014-01-01

    Cell polarity manifested by asymmetric distribution of cargoes, such as receptors and transporters, within the plasma membrane (PM) is crucial for essential functions in multicellular organisms. In plants, cell polarity (re)establishment is intimately linked to patterning processes. Despite the

  17. Fetal and infant growth patterns associated with total and abdominal fat distribution in school-age children

    NARCIS (Netherlands)

    Gishti, O.; Gaillard, R.; Manniesing, R.; Abrahamse-Berkeveld, M.; Beek, E.M. van der; Heppe, D.H.M.; Steegers, E.A.P.; Hofman, A.; Duijts, L.; Durmus, B.u.; Jaddoe, V.W.

    2014-01-01

    Context: Higher infant growth rates are associated with an increased risk of obesity in later life. Objective: We examined the associations of longitudinally measured fetal and infant growth patterns with total and abdominal fat distribution in childhood. Design, Settings and participants:We

  18. Earthworm abundance and distribution pattern in contrasting plant communities within a tropical wet forest in Puerto Rico

    Science.gov (United States)

    G. Gonzalez; X. Zou; A. Sabat; N. Fetcher

    1999-01-01

    Plant communities may impose strong control on soil fauna properties. We examined the abundance and distribution pattern of earthworms in two contrasting plant communities within a tropical wet forest in Puerto Rico. The Dacryodes community occurs in well-drained soils and is dominated by Dacryodes excels, Manilkara bidentata, Guarea guidonea, and Sloanea berteriana....

  19. Late Quaternary palynology in marine sediments: a synthesis of the understanding of pollen distribution patterns in the NW African setting.

    NARCIS (Netherlands)

    Hooghiemstra, H.; Lézine, A.M.; Leroy, S.A.G.; Dupont, L.; Marret, F.

    2006-01-01

    Abstract After a review of the first steps in marine palynology, we show that the understanding of the northwest African setting is crucial to evaluate the potential of marine palynological studies elsewhere. We studied distribution patterns of pollen grains in recent marine sediments off NW Africa

  20. Patterns of organic osmolytes in two marine bivalves, Macoma balthica, and Mytilus spp., along their European distribution

    NARCIS (Netherlands)

    Kube, S.; Gerber, A.; Jansen, J.M.; Schiedek, D.

    2006-01-01

    Patterns of nine intracellular free amino acids (FAA), which are utilized as organic osmolytes for salinity-induced cell volume regulation in marine osmoconformers, were compared in five Macoma balthica populations and seven Mytilus spp. populations along their European distribution. Three types of

  1. Distribution of airborne microbes and antibiotic susceptibility pattern of bacteria during Gwalior trade fair, Central India.

    Science.gov (United States)

    Yadav, Jayprakash; Kumar, Awanish; Mahor, Pawan; Goel, Ajay Kumar; Chaudhary, Hotam Singh; Yadava, Pramod Kumar; Yadav, Hariom; Kumar, Pramod

    2015-07-01

    Research into the distribution of bioaerosols during events associated with huge groups of people is lacking, especially in developing countries. The purpose of this study was to understand the distribution pattern of bioaerosols during an annual trade fair in the historical city of Gwalior, central India, a very important historical fair that was started by the King of Gwalior Maharaja Madho Rao in 1905. Air samples were collected from six different sites at the fair ground and three different sites in a residential area before/during/after the fair using an impactor sampler on microbial content test agar and rose bengal agar for total bacteria and fungi, respectively. The representative strains of bacteria and fungi were further identified and selected bacterial strains were subjected to antibiotic susceptibility testing according to US Clinical and Laboratory Standards Institute (CLSI) guidelines. The bacterial bioaerosol count [colony-forming units (CFU)/m(3)] at fair sites was found to be 9.0 × 10(3), 4.0 × 10(4), and 1.0 × 10(4) before the start of the fair, during the fair, and after the fair, respectively. The fungal bioaerosol count at fair sites was 2.6 × 10(3) CFU/m(3), 6.3 × 10(3) CFU/m(3), and 1.7 × 10(3) CFU/m(3) before the fair, during the fair, and after the fair, respectively. Bacterial/fungal bioaerosols during-fair were increased significantly from the bacterial/fungal bioaerosols of the before-fair period (p fair sites during the event (p fair ground was significantly increased during-fair and was still higher in the after-fair period. Methicillin-resistant staphylococci (MRS) were also reported at the fair ground. The study indicates significantly higher bacterial and fungal bioaerosols during the fair event. Therefore, further research is needed to explore the health aspects and guidelines to control microbial load during such types of events. Copyright © 2013. Published by Elsevier B.V.

  2. Patterns of Carbon Source and Sink Distribution in Canada's Forests Resulting From Disturbance and Climate Change

    Science.gov (United States)

    Chen, J. M.; Cihlar, J.; Amiro, B.; Ju, W.; Price, D.; Liu, J.; Pan, J.

    2001-12-01

    Major forest disturbance includes fires, inset-induced mortality, and timber harvest. The direct release of carbon from Canada's forests due to disturbance amounts to 150 Mt/y in some years, which is about 1.5 percent of the net primary productivity (NPP) of all Canada's forests (~420 Mha.). The mean carbon release due to disturbance in 1990-1998 was about 60 percent of net ecosystem productivity (NEP) of all undisturbed Canada's forests. The disturbance effects have been estimated in previous studies, either based on eco-region disturbance statistics in 5 year time steps, or Canada-mean values in annual time steps. However, large improvements in the estimation are still possible when spatially explicit information is used. For this purpose, 10-day cloud-free synthesis images of VEGETATION onboard SPOT-4, acquired in June-August, 1998, are used to derive a Canada-wide fire scar age distribution for up to 25 years. The spatial resolution of the fire scars is 1 km. This information is combined with gridded forest inventory of forest stand age at 10 km resolution to complete the age distribution at 1998. Forest regeneration is assumed to start 1 year after disturbance, but the regrowth is slower at locations with lower annual temperatures. An ecosystem model, named InTEC, is used to assimilate satellite-derived land cover and leaf area index maps, gridded climate (1901-1998) and soil data, and this forest stand age map, and to calculate NPP, NEP and net biome productivity (NBP) for each 1 km pixel at annual time steps. Both direct carbon release and forest regrowth after disturbance are modeled. The NBP maps of Canada in recent years show: (i) large spatial variations corresponding to patterns of recent fire scars and forest types, and (ii) a general south-to-north gradient of decreasing sink strength and increasing source strength. This gradient results mostly from different effects of temperature increase on growing season length, nutrient mineralizaton, and

  3. Seasonal Habitat Patterns of Japanese Common Squid (Todarodes Pacificus Inferred from Satellite-Based Species Distribution Models

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    Irene D. Alabia

    2016-11-01

    Full Text Available The understanding of the spatio-temporal distributions of the species habitat in the marine environment is central to effectual resource management and conservation. Here, we examined the potential habitat distributions of Japanese common squid (Todarodes pacificus in the Sea of Japan during a four-year period. The seasonal patterns of preferential habitat were inferred from species distribution models, built using squid occurrences detected from night-time visible images and remotely-sensed environmental factors. The predicted squid habitat (i.e., areas with high habitat suitability revealed strong seasonal variability, characterized by a reduction of potential habitat, confined off of the southern part of the basin during the winter–spring period (December–May. Apparent expansion of preferential habitat occurred during summer–autumn months (June–November, concurrent with the formation of highly suitable habitat patches in certain regions of the Sea of Japan. These habitat distribution patterns were in response to changes in oceanographic conditions and synchronous with seasonal migration of squid. Moreover, the most important variables regulating the spatio-temporal patterns of suitable habitat were sea surface temperature, depth, sea surface height anomaly, and eddy kinetic energy. These variables could affect the habitat distributions through their impacts on growth and survival of squid, local nutrient transport, and the availability of favorable spawning and feeding grounds.

  4. More about the geographical pattern of distribution of the genus Pseudouroplectes Lourenço, 1995 (Scorpiones: Buthidae) from Madagascar.

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    Lourenço, Wilson R; Wilmé, Lucienne; Waeber, Patrick O

    2016-01-01

    The genus Pseudouroplectes Lourenço, 1995 (Buthidae) remains among the less speciose Malagasy genera and all the known species are extremely rare. A new species is described from the dry forests in the Tsingy formations of the National Park Bemaraha, extending the distribution of the genus further north. Once again, the single holotype specimen was obtained by extraction with the use of Berlese system. With the description of the new species, the distributional pattern of this genus is confirmed for dry forest formations from the south to the middle of the island; however, for the first time the group's distribution overlaps that of another micro-scorpion genus, Microcharmus Lourenço, 1995. The distribution patterns of the humicolous micro-scorpions endemic to Madagascar are considered to further explore the "Neogrosphus rule" as a possible explanation of global species distribution patterns in changing environments. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  5. Comparative demography of two co-occurring Linum species with different distribution patterns.

    Science.gov (United States)

    Münzbergová, Z

    2013-11-01

    Understanding similarities and differences in population dynamics of closely related species is a key prerequisite in attempts to apply knowledge obtained in one species to another species, e.g., for the purpose of predicting future fate of populations of various rare species. It can be expected that species will have similar population dynamics if they are closely related and share similar habitats. Contrasting population sizes and distribution patterns may, however, indicate that the population dynamics will be different. To understand similarities and differences in population dynamics of closely related species, I studied demography of two congeneric endangered species, Linum flavum and L. tenuifolium co-occurring in dry grasslands. Linum flavum occurs with a lower number of large populations, while L. tenuifolium occurs as a large number of small populations. The results showed that L. flavum had higher population growth rates, relied more on survival and growth and its populations were more persistent. In contrast, populations of L. tenuifolium were more prone to extinction and frequent recolonisation was necessary for their survival in the landscape. This was in accordance with observed population sizes of the two species and their frequency in the landscape. The results indicate that despite being closely related and occurring in the same habitat types, the two Linum species have different growth strategies. The strong differences in population dynamics between the two species suggest that similarity in population sizes and frequency of the species in the landscape may be more important when attempting to transfer knowledge between species than is taxonomic relatedness. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  6. [Species-abundance distribution patterns along succession series of Phyllostachys glauca forest in a limestone mountain].

    Science.gov (United States)

    Shi, Jian-min; Fan, Cheng-fang; Liu, Yang; Yang, Qing-pei; Fang, Kai; Fan, Fang-li; Yang, Guang-yao

    2015-12-01

    To detect the ecological process of the succession series of Phyllostachys glauca forest in a limestone mountain, five niche models, i.e., broken stick model (BSM), niche preemption model (NPM), dominance preemption model (DPM), random assortment model (RAM) and overlap- ping niche model (ONM) were employed to describe the species-abundance distribution patterns (SDPs) of 15 samples. χ² test and Akaike information criterion (AIC) were used to test the fitting effects of the five models. The results showed that the optimal SDP models for P. glauca forest, bamboo-broadleaved mixed forest and broadleaved forest were DPM (χ² = 35.86, AIC = -69.77), NPM (χ² = 1.60, AIC = -94.68) and NPM (χ² = 0.35, AIC = -364.61), respectively. BSM also well fitted the SDP of bamboo-broadleaved mixed forest and broad-leaved forest, while it was unsuitable to describe the SDP of P. glauca forest. The fittings of RAM and ONM in the three forest types were all rejected by the χ² test and AIC. With the development of community succession from P. glauca forest to broadleaved forest, the species richness and evenness increased, and the optimal SDP model changed from DPM to NPM. It was inferred that the change of ecological process from habitat filtration to interspecific competition was the main driving force of the forest succession. The results also indicated that the application of multiple SDP models and test methods would be beneficial to select the best model and deeply understand the ecological process of community succession.

  7. Pattern and distribution of pedestrian injuries in fatal road traffic accidental cases in Dharan, Nepal.

    Science.gov (United States)

    Mandal, Birendra Kumar; Yadav, Biswa Nath

    2014-07-01

    Road traffic injuries are one of the leading causes of death in the world. The present study aims at evaluation of pattern and distribution of injuries among pedestrians thereby planning successful measures to minimize fatalities. The present study was conducted in the Department of Forensic Medicine and Toxicology, B.P. Koirala Institute of Health Sciences, Dharan, Nepal. This study included 50 cases of pedestrian victims of fatal road traffic accident, brought for medico-legal postmortem examination. Highest number (17 or 21.3%) of fatalities occurred in the 41-50 years age group followed by the age group 31-40 years (15 or 18.7%). Male victims outnumbered female resulting in male to female ratio of 1.8:1. Most of the pedestrians were illiterate (26 or 32.5%) followed by those who were educated up to primary school (14 or 17.5%). Nearly half of the cases (38 or 47.5%), four or more wheelers - heavy vehicles - were involved. Fracture was the most common type of injuries (55 or 28.9%) followed by laceration (50 or 26.3%). In 44 (55%) cases, primary impact injuries were noted, secondary impact injuries in 55 (68.7%) cases, and secondary injuries in 62 (77.5%) cases. More than one-fourth (22 or 27.5%) of the deaths were due to pelvic and extremities injuries. Pedestrians, people who travel by foot, wheelchair, stroller, or similar means, are most vulnerable users of the road. Before head out on foot for a stroll, power walk, or errand, there are important safety tips to remember. A greater awareness about traffic rules will go a long way in curbing the incidence of fatal pedestrian accidents.

  8. A geomorphic analysis of Sinai's drainage pattern. Evidence for interpreting the distribution of uplift?

    Science.gov (United States)

    Oswald, Angela; Stüwe, Kurt; Hanke, Gustav

    2013-04-01

    A variety of quantitative geomorphologic methods have proven useful to infer aspects of the interplay between tectonics and surface processes and have been applied to various regions in the world. For example, quantitative analysis of drainage systems may be used to investigate the formation of mountain belts where the exposure of bedrock can be linked with tectonic processes. Sinai Peninsula, which is located at the northernmost Red Sea, shows what appears to be a fluvial landscape despite present aridity. Its geomorphology is suitable for a quantitative geomorphologic interpretation using a classic stream power approach. Geomorphologic parameters were derived through analysis of the ASTER digital elevation model (DEM). Steepness and concavity index were extracted from slope-area relationships along channel profiles. Although parameters like knickpoints along channels are typically controlled by complex mechanisms, they may be used to interpret different regimes of uplift. Sinuosity has been calculated from plan channel coordinates in order to differentiate between fluvial and fault dominated channels and channel segments. Because of possible overprinting of fluvial features by present day arid climate erosion and sedimentation processes, the DEM-based analysis needs to be supplemented with photographic images and field observations in order to assess the significance of the single parameter values. The spatial distribution of geomorphic parameter values is compared to the large scale topographic and slope pattern and correlated with the different tectonic regimes acting on Sinai, namely the divergent rifting of the Gulf of Suez in the West and the strike slip dominated opening of the Gulf of Aqaba, whereas Northern Sinai is tilted towards the Mediterranean.

  9. Spatio-temporal patterns of distribution of West Nile virus vectors in eastern Piedmont Region, Italy

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    Bisanzio Donal

    2011-12-01

    Full Text Available Abstract Background West Nile Virus (WNV transmission in Italy was first reported in 1998 as an equine outbreak near the swamps of Padule di Fucecchio, Tuscany. No other cases were identified during the following decade until 2008, when horse and human outbreaks were reported in Emilia Romagna, North Italy. Since then, WNV outbreaks have occurred annually, spreading from their initial northern foci throughout the country. Following the outbreak in 1998 the Italian public health authority defined a surveillance plan to detect WNV circulation in birds, horses and mosquitoes. By applying spatial statistical analysis (spatial point pattern analysis and models (Bayesian GLMM models to a longitudinal dataset on the abundance of the three putative WNV vectors [Ochlerotatus caspius (Pallas 1771, Culex pipiens (Linnaeus 1758 and Culex modestus (Ficalbi 1890] in eastern Piedmont, we quantified their abundance and distribution in space and time and generated prediction maps outlining the areas with the highest vector productivity and potential for WNV introduction and amplification. Results The highest abundance and significant spatial clusters of Oc. caspius and Cx. modestus were in proximity to rice fields, and for Cx. pipiens, in proximity to highly populated urban areas. The GLMM model showed the importance of weather conditions and environmental factors in predicting mosquito abundance. Distance from the preferential breeding sites and elevation were negatively associated with the number of collected mosquitoes. The Normalized Difference Vegetation Index (NDVI was positively correlated with mosquito abundance in rice fields (Oc. caspius and Cx. modestus. Based on the best models, we developed prediction maps for the year 2010 outlining the areas where high abundance of vectors could favour the introduction and amplification of WNV. Conclusions Our findings provide useful information for surveillance activities aiming to identify locations where the

  10. Species diversity and distribution patterns of the ants of Amazonian Ecuador.

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    Kari T Ryder Wilkie

    Full Text Available Ants are among the most diverse, abundant and ecologically significant organisms on earth. Although their species richness appears to be greatest in the New World tropics, global patterns of ant diversity and distribution are not well understood. We comprehensively surveyed ant diversity in a lowland primary rainforest in Western Amazonia, Ecuador using canopy fogging, pitfall traps, baits, hand collecting, mini-Winkler devices and subterranean probes to sample ants. A total of 489 ant species comprising 64 genera in nine subfamilies were identified from samples collected in only 0.16 square kilometers. The most species-rich genera were Camponotus, Pheidole, Pseudomyrmex, Pachycondyla, Brachymyrmex, and Crematogaster. Camponotus and Pseudomyrmex were most diverse in the canopy, while Pheidole was most diverse on the ground. The three most abundant ground-dwelling ant genera were Pheidole, Solenopsis and Pyramica. Crematogaster carinata was the most abundant ant species in the canopy; Wasmannia auropunctata was most abundant on the ground, and the army ant Labidus coecus was the most abundant subterranean species. Ant species composition among strata was significantly different: 80% of species were found in only one stratum, 17% in two strata, and 3% in all three strata. Elevation and the number of logs and twigs available as nest sites were significant predictors of ground-dwelling ant species richness. Canopy species richness was not correlated with any ecological variable measured. Subterranean species richness was negatively correlated with depth in the soil. When ant species were categorized using a functional group matrix based on diet, nest-site preference and foraging ecology, the greatest diversity was found in Omnivorous Canopy Nesters. Our study indicates ant species richness is exceptionally high at Tiputini. We project 647-736 ant species in this global hotspot of biodiversity. Considering the relatively small area surveyed, this

  11. Species diversity and distribution patterns of the ants of Amazonian Ecuador.

    Science.gov (United States)

    Ryder Wilkie, Kari T; Mertl, Amy L; Traniello, James F A

    2010-10-01

    Ants are among the most diverse, abundant and ecologically significant organisms on earth. Although their species richness appears to be greatest in the New World tropics, global patterns of ant diversity and distribution are not well understood. We comprehensively surveyed ant diversity in a lowland primary rainforest in Western Amazonia, Ecuador using canopy fogging, pitfall traps, baits, hand collecting, mini-Winkler devices and subterranean probes to sample ants. A total of 489 ant species comprising 64 genera in nine subfamilies were identified from samples collected in only 0.16 square kilometers. The most species-rich genera were Camponotus, Pheidole, Pseudomyrmex, Pachycondyla, Brachymyrmex, and Crematogaster. Camponotus and Pseudomyrmex were most diverse in the canopy, while Pheidole was most diverse on the ground. The three most abundant ground-dwelling ant genera were Pheidole, Solenopsis and Pyramica. Crematogaster carinata was the most abundant ant species in the canopy; Wasmannia auropunctata was most abundant on the ground, and the army ant Labidus coecus was the most abundant subterranean species. Ant species composition among strata was significantly different: 80% of species were found in only one stratum, 17% in two strata, and 3% in all three strata. Elevation and the number of logs and twigs available as nest sites were significant predictors of ground-dwelling ant species richness. Canopy species richness was not correlated with any ecological variable measured. Subterranean species richness was negatively correlated with depth in the soil. When ant species were categorized using a functional group matrix based on diet, nest-site preference and foraging ecology, the greatest diversity was found in Omnivorous Canopy Nesters. Our study indicates ant species richness is exceptionally high at Tiputini. We project 647-736 ant species in this global hotspot of biodiversity. Considering the relatively small area surveyed, this region of western

  12. Seasonality and Distribution Pattern of Brown Marmorated Stink Bug (Hemiptera: Pentatomidae) in Virginia Vineyards.

    Science.gov (United States)

    Basnet, S; Kuhar, T P; Laub, C A; Pfeiffer, D G

    2015-08-01

    Brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is a highly polyphagous invasive insect pest from eastern Asia that feeds on numerous fruit, vegetable, and field crops. Four commercial vineyards in Virginia were sampled in 2012 and 2013 to study the basic biology, seasonality, and distribution pattern of H. halys in vineyards. At each vineyard, two blocks were selected. Weekly 3-min timed count visual samplings were performed in border and interior sections from late May until mid-September. Overwintering adult bugs were first detected in vineyards in May; however, the timing of first detection differed among vineyards. Egg masses were found primarily in June and July, and were usually found on the lower surface of grape leaves, although they were occasionally on the upper leaf surface, on the berry, or on the rachis. All developmental stages of H. halys were found in vineyards, suggesting that grape can serve as a reproductive host for H. halys. Substantial variation in H. halys densities was found among vineyards and throughout the growing season. The first instars were found on egg masses and after molting, dispersed throughout the grape vines. The date on which the first egg mass was collected was considered as a biofix. Based on a degree-day model, there were sufficient degree-days for completion of a generation in Virginia vineyards. Significantly higher numbers of H. halys were collected in border sections compared with interior sections. These results are discussed in relation to the potential pest status of H. halys in vineyards and implications for possible control strategies. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Pattern of Spatial Distribution and Temporal Variation of Atmospheric Pollutants during 2013 in Shenzhen, China

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    Xiaolin Xia

    2016-12-01

    Full Text Available Air pollution caused by atmospheric particulate and gaseous pollutants has drawn broad public concern globally. In this paper, the spatial-temporal distributions of major air pollutants in Shenzhen from March 2013 to February 2014 are discussed. In this study, ground-site monitoring data from 19 monitoring sites was used and spatial interpolation and spatial autocorrelation methods were applied to analyze both spatial and temporal characteristics of air pollutants in Shenzhen City. During the study period, the daily average concentrations of Particulate Matter (PM10 and PM2.5 ranged from 16–189 μg/m3 and 10–136 μg/m3, respectively, with 13 and 44 over-limit days, indicating that particulate matter was the primary air pollutant in Shenzhen. The highest PM occupation in the polluted air was observed in winter, indicating that fine particulate pollution was most serious in winter. Meanwhile, seasonal agglomeration patterns for six kinds of air pollutants showed that Guangming, Baoan, Nanshan, and the northern part of Longgang were the most polluted areas and PMs were their primary air pollutants. In addition, wind scale and rainfall played an important role in dissipating air pollutant in Shenzhen. The wind direction impacted the air pollution level in Shenzhen in multiple ways: the highest concentrations for all air pollutants all occurred on days with a northeast wind; the second highest ones appeared on the days with no wind. The concentrations on days with north-related winds are higher on average than those of days with south-related winds.

  14. Unravelling a biogeographical knot: origin of the 'leapfrog' distribution pattern of Australo-Papuan sooty owls (Strigiformes) and logrunners (Passeriformes).

    Science.gov (United States)

    Norman, J A; Christidis, L; Joseph, L; Slikas, B; Alpers, D

    2002-10-22

    Molecular analysis of two Australo-Papuan rainforest birds exhibiting correlated 'leapfrog' patterns were used to elucidate the evolutionary origin of this unusual pattern of geographical differentiation. In both sooty owls (Tyto) and logrunners (Orthonyx), phenotypically similar populations occupy widely disjunct areas (central-eastern Australia and upland New Guinea) with a third, highly distinctive population, occurring between them in northeastern Queensland. Two mechanisms have been proposed to explain the origin of leapfrog patterns in avian distributions: recent shared ancestry of terminal populations and unequal rates or phenotypic change among populations. As the former should generate correlated patterns of phenotypic and genetic differentiation, we tested for a sister relationship between populations from New Guinea and central-eastern Australia using nuclear and mitochondrial DNA sequences. The resulting phylogenies not only refute recent ancestry as an explanation for the leapfrog pattern, but provide evidence of vastly different spatio-temporal histories for sooty owls and logrunners within the Australo-Papuan rainforests. This incongruence indicates that the evolutionary processes responsible for generating leapfrog patterns in these co-distributed taxa are complex, possibly involving a combination of selection and drift in sooty owls and convergence or retention of ancestral characteristics in logrunners.

  15. Distributional patterns of decapod crustaceans in the circum-Mediterranean area during the Oligo-Miocene

    Science.gov (United States)

    Hyžný, Matúš

    2015-04-01

    During the Oligocene and Miocene, the circum-Mediterranean area was a complex network of (mostly) shallow marine basins. Significant biogeographic differentiation of this area has been documented (Harzhauser et al. 2007), mainly during the Miocene, when connections between Proto-Mediterranean, Paratethys and Proto-Indo-West Pacific were intermittently opening and closing. These seaways allowed migration of marine faunas. Distributional patterns has so far been discussed for several different animal groups, especially for molluscs (e.g. Studencka et al. 1998; Harzhauser et al. 2002, 2003, 2007). To test these patterns with decapod crustaceans, a database has been compiled including all previously published Oligocene and Miocene decapod occurrences and newly gathered data from examined material deposited in the institutional collections. Decapod associations have been significant components of marine habitats since the Mesozoic times with ever-increasing importance throughout the Cenozoic. Müller (1979) argued that brachyuran decapods are among the best zoogeographical indicators. Although decapods were used as such indicators before (e.g. Schweitzer 2001; Feldmann & Schweitzer 2006), no detailed analysis of the circum-Mediterranean taxa has been conducted so far. Based on proposed anti-estuarine circulation pattern, decapods originated in the Proto-Mediterranean, and migrated both into the North Sea and the Paratethys. Moreover, during the Early Miocene the Rhine Graben served as a connection between the North Sea and the Paratethys which enabled faunal exchange. The Middle Miocene Proto-Mediterranean and Paratethys decapod assemblages as taken together were relatively homogeneous, although distinct due to increasing rate of endemites in the Paratethys during the Miocene. The research has been supported by FWF: Lise Meitner Program M 1544-B25. References Feldmann R.M. & Schweitzer C.E. 2006: Paleobiogeography of Southern Hemisphere decapod Crustacea. J. Paleontol

  16. Elevational gradients in fish diversity in the Himalaya: water discharge is the key driver of distribution patterns.

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    Jay P Bhatt

    Full Text Available BACKGROUND: Studying diversity and distribution patterns of species along elevational gradients and understanding drivers behind these patterns is central to macroecology and conservation biology. A number of studies on biogeographic gradients are available for terrestrial ecosystems, but freshwater ecosystems remain largely neglected. In particular, we know very little about the species richness gradients and their drivers in the Himalaya, a global biodiversity hotspot. METHODOLOGY/PRINCIPAL FINDINGS: We collated taxonomic and distribution data of fish species from 16 freshwater Himalayan rivers and carried out empirical studies on environmental drivers and fish diversity and distribution in the Teesta river (Eastern Himalaya. We examined patterns of fish species richness along the Himalayan elevational gradients (50-3800 m and sought to understand the drivers behind the emerging patterns. We used generalized linear models (GLM and generalized additive models (GAM to examine the richness patterns; GLM was used to investigate relationship between fish species richness and various environmental variables. Regression modelling involved stepwise procedures, including elimination of collinear variables, best model selection, based on the least Akaike's information criterion (AIC and the highest percentage of deviance explained (D(2. This maiden study on the Himalayan fishes revealed that total and non-endemic fish species richness monotonously decrease with increasing elevation, while endemics peaked around mid elevations (700-1500 m. The best explanatory model (synthetic model indicated that water discharge is the best predictor of fish species richness patterns in the Himalayan rivers. CONCLUSIONS/SIGNIFICANCE: This study, carried out along one of the longest bioclimatic elevation gradients of the world, lends support to Rapoport's elevational rule as opposed to mid domain effect hypothesis. We propose a species-discharge model and contradict

  17. Elevational gradients in fish diversity in the Himalaya: water discharge is the key driver of distribution patterns.

    Science.gov (United States)

    Bhatt, Jay P; Manish, Kumar; Pandit, Maharaj K

    2012-01-01

    Studying diversity and distribution patterns of species along elevational gradients and understanding drivers behind these patterns is central to macroecology and conservation biology. A number of studies on biogeographic gradients are available for terrestrial ecosystems, but freshwater ecosystems remain largely neglected. In particular, we know very little about the species richness gradients and their drivers in the Himalaya, a global biodiversity hotspot. We collated taxonomic and distribution data of fish species from 16 freshwater Himalayan rivers and carried out empirical studies on environmental drivers and fish diversity and distribution in the Teesta river (Eastern Himalaya). We examined patterns of fish species richness along the Himalayan elevational gradients (50-3800 m) and sought to understand the drivers behind the emerging patterns. We used generalized linear models (GLM) and generalized additive models (GAM) to examine the richness patterns; GLM was used to investigate relationship between fish species richness and various environmental variables. Regression modelling involved stepwise procedures, including elimination of collinear variables, best model selection, based on the least Akaike's information criterion (AIC) and the highest percentage of deviance explained (D(2)). This maiden study on the Himalayan fishes revealed that total and non-endemic fish species richness monotonously decrease with increasing elevation, while endemics peaked around mid elevations (700-1500 m). The best explanatory model (synthetic model) indicated that water discharge is the best predictor of fish species richness patterns in the Himalayan rivers. This study, carried out along one of the longest bioclimatic elevation gradients of the world, lends support to Rapoport's elevational rule as opposed to mid domain effect hypothesis. We propose a species-discharge model and contradict species-area model in predicting fish species richness. We suggest that drivers of

  18. Predicting the distribution of spiral waves from cell properties in a developmental-path model of Dictyostelium pattern formation.

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    Daniel Geberth

    2009-07-01

    Full Text Available The slime mold Dictyostelium discoideum is one of the model systems of biological pattern formation. One of the most successful answers to the challenge of establishing a spiral wave pattern in a colony of homogeneously distributed D. discoideum cells has been the suggestion of a developmental path the cells follow (Lauzeral and coworkers. This is a well-defined change in properties each cell undergoes on a longer time scale than the typical dynamics of the cell. Here we show that this concept leads to an inhomogeneous and systematic spatial distribution of spiral waves, which can be predicted from the distribution of cells on the developmental path. We propose specific experiments for checking whether such systematics are also found in data and thus, indirectly, provide evidence of a developmental path.

  19. Both inherited susceptibility and environmental exposure determine the low-density lipoprotein-subfraction pattern distribution in healthy Dutch families

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    Graaf, J. de; Swinkels, D.W.; Haan, A.F.J. de; Demacker, P.N.M.; Stalenhoef, A.F.H. (University Hospital, Nijmegen (Netherlands))

    1992-12-01

    A lipoprotein profile characterized by a predominance of small, dense, low-density lipoprotein (LDL) particles has been associated with an increased risk of atherosclerosis. To investigate whether genetic factors are involved in determining this heavy LDL subfraction pattern, this study was undertaken with the aim of resolving the effects that major genes, multifactorial heritability, and environmental exposures have on the LDL subfraction pattern. In a random sample of 19 healthy Dutch families including 162 individuals, the distribution of the LDL subfraction pattern was determined by density gradient ultracentrifugation. For each subject a specific LDL subfraction profile was observed, characterized by the relative contribution of the three major LDL subfractions - LDL1 (d = 1.030-1.033 g/ml), LDL2 (d = 1.033-1.040 g/ml), and LDL3 (d = 1.040-1.045 g/ml) - to total LDL. A continuous variable, parameter K, was defined to characterize each individual LDL subfraction pattern. Complex segregation analysis of this quantitative trait, under a model which includes a major locus, polygenes, and both common and random environment, was applied to analyze the distribution of the LDL subfraction pattern in these families. The results indicate that the LDL subfraction pattern, described by parameter K, is controlled by a major autosomal, highly penetrant, recessive allele with a population frequency of .19 and an additional multifactorial inheritance component. The results indicate that genetic influences as well as environmental exposure, sex, age and hormonal status in women are important in determining the distribution of the LDL subfraction patterns in this population and that these influences may contribute to the explanation of familial clustering of coronary heart disease. 40 refs., 3 figs., 8 tabs.

  20. Pattern of tick aggregation on mice: larger than expected distribution tail enhances the spread of tick-borne pathogens.

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    Luca Ferreri

    2014-11-01

    Full Text Available The spread of tick-borne pathogens represents an important threat to human and animal health in many parts of Eurasia. Here, we analysed a 9-year time series of Ixodes ricinus ticks feeding on Apodemus flavicollis mice (main reservoir-competent host for tick-borne encephalitis, TBE sampled in Trentino (Northern Italy. The tail of the distribution of the number of ticks per host was fitted by three theoretical distributions: Negative Binomial (NB, Poisson-LogNormal (PoiLN, and Power-Law (PL. The fit with theoretical distributions indicated that the tail of the tick infestation pattern on mice is better described by the PL distribution. Moreover, we found that the tail of the distribution significantly changes with seasonal variations in host abundance. In order to investigate the effect of different tails of tick distribution on the invasion of a non-systemically transmitted pathogen, we simulated the transmission of a TBE-like virus between susceptible and infective ticks using a stochastic model. Model simulations indicated different outcomes of disease spreading when considering different distribution laws of ticks among hosts. Specifically, we found that the epidemic threshold and the prevalence equilibria obtained in epidemiological simulations with PL distribution are a good approximation of those observed in simulations feed by the empirical distribution. Moreover, we also found that the epidemic threshold for disease invasion was lower when considering the seasonal variation of tick aggregation.

  1. Distributed Storage Algorithm for Geospatial Image Data Based on Data Access Patterns

    OpenAIRE

    Shaoming Pan; Yongkai Li; Zhengquan Xu; Yanwen Chong

    2015-01-01

    Declustering techniques are widely used in distributed environments to reduce query response time through parallel I/O by splitting large files into several small blocks and then distributing those blocks among multiple storage nodes. Unfortunately, however, many small geospatial image data files cannot be further split for distributed storage. In this paper, we propose a complete theoretical system for the distributed storage of small geospatial image data files based on mining the access pa...

  2. Study on Horizontally Polarized Omnidirectional Microstrip Antenna

    Directory of Open Access Journals (Sweden)

    Kun Wei

    2016-01-01

    Full Text Available A horizontally polarized omnidirectional microstrip antenna is proposed in this paper. The structure of designed antenna is with two back-to-back horizontally polarized microstrip antenna elements. Gain variation on main radiation plane of this new antenna is analyzed and radiation theory is deduced; formula of directivity on main radiation plane is given. Better omnidirectional characteristic of this antenna can be obtained by decreasing patch physical length. Both simulated and measured results verify the omnidirectional radiation patterns and input impedance characteristics. Good omnidirectional radiation patterns (gain variation in E-plane less than ±0.4 dBi and input impedance characteristics are obtained; moreover, cross polarization less than −20 dBi is achieved.

  3. Community Structure and Distribution Pattern of Intertidal Invertebrate Macrofauna at Some Anthropogenically Influenced Coasts of Kathiawar Peninsula (India

    Directory of Open Access Journals (Sweden)

    Poonam Bhadja

    2014-01-01

    Full Text Available Present communication reports the community structure and distribution pattern of intertidal invertebrate macrofauna at four shores of the Kathiawar peninsular coastline off the Arabian Sea (India. The selected shores have different levels of human activities. Present report tests three hypotheses; that is, (i distribution of invertebrate macrofauna in these shores is influenced by space and time, (ii abiotic factors have a profound influence on the distribution pattern of intertidal macrofaunal assemblages, and (iii human activities influence the community structure of the intertidal invertebrate macrofauna at these shores. To test these hypotheses, spatiotemporal variations in different ecological indices were studied. A total of 60 species from six phyla were considered for the study. High species diversity was recorded during winter and monsoon seasons in almost all the shores studied. It was also evident that a few environmental factors had a cumulative influence on the distribution pattern of intertidal macrofauna. Significant spatial variations in the species diversity and evenness were also observed. Though the shores studied have similar coast characteristics and climatic conditions, they face different levels of human activities. Therefore, the observed variations in the intertidal faunal assemblage were possibly caused by anthropogenic stress.

  4. Distribution of coronoid fracture lines by specific patterns of traumatic elbow instability

    NARCIS (Netherlands)

    Mellema, Jos J.; Doornberg, Job N.; Dyer, George S. M.; Ring, David

    2014-01-01

    To determine if specific coronoid fractures relate to specific overall traumatic elbow instability injury patterns and to depict any relationship on fracture maps and heat maps. We collected 110 computed tomography (CT) studies from patients with coronoid fractures. Fracture types and pattern of

  5. The study on the effect of pattern density distribution on the STI CMP process

    Science.gov (United States)

    Sub, Yoon Myung; Hian, Bernard Yap Tzen; Fong, Lee It; Anak, Philip Menit; Minhar, Ariffin Bin; Wui, Tan Kim; Kim, Melvin Phua Twang; Jin, Looi Hui; Min, Foo Thai

    2017-08-01

    The effects of pattern density on CMP characteristics were investigated using specially designed wafer for the characterization of pattern-dependencies in STI CMP [1]. The purpose of this study is to investigate the planarization behavior based on a direct STI CMP used in cerium (CeO2) based slurry system in terms of pattern density variation. The minimal design rule (DR) of 180nm generation technology node was adopted for the mask layout. The mask was successfully applied for evaluation of a cerium (CeO2) abrasive based direct STI CMP process. In this study, we described a planarization behavior of the loading-effects of pattern density variation which were characterized with layout pattern density and pitch variations using masks mentioned above. Furthermore, the characterizing pattern dependent on the variations of the dimensions and spacing features, in thickness remaining after CMP, were analyzed and evaluated. The goal was to establish a concept of library method which will be used to generate design rules reducing the probability of CMP-related failures. Details of the characterization were measured in various layouts showing different pattern density ranges and the effects of pattern density on STI CMP has been discussed in this paper.

  6. [Faunal characteristics and distribution pattern of crustaceans in the vicinity of Pearl River estuary].

    Science.gov (United States)

    Huang, Zi-Rong; Sun, Dian-Rong; Chen, Zuo-Zhi; Zhang, Han-Hua; Wang, Xue-Hui; Wang, Yue-Zhong; Fang, Hong-Da; Dong, Yan-Hong

    2009-10-01

    Based on the data of bottom trawl surveys in the vicinity of Pearl River estuary in August (summer), October (autumn), December (winter) 2006, and April (spring) 2007, the faunal characteristics and distribution pattern of crustaceans were analyzed. A total of 54 species belonging to 25 genera, 17 families, and 2 orders were collected, including 22 species of shrimps, 22 species of crabs, and 10 species of squills. Most of the crustaceans were tropical-subtropical warm-water species, a few of them were eurythermal species, and no warm-water and cold-water species occurred. Euryhaline species were most abundant, followed by halophile species, and the low-salinity species were the least. Most of the crustacean species belonged to the fauna of Indian Ocean-western Pacific Ocean. The faunal assemblages were closer to those of the East China Sea, Philippine Sea, Indonesia Sea, and the Japan Sea, and estranger with those of the Yellow Sea, Bohai Sea, and Korea Sea. The dominant species were Metapenaeus joyner, Oratosquilla oratoria, Charybdis miles, Portunus sanguinolentus, Harpiosquilla harpax, Charybdis feriatus, Charybdis japonica, Oratosquilla nepa, Solenocera crassicornis, Portunus trituberculatus, and Calappa philargius. The crustaceans had the largest species number (33) in autumn and the least one (26) in spring, and the highest stock density at the water depth of < 40 m, especially at 10-20 m. The average stock density of the crustaceans was estimated to be 99.60 kg x km(-2), with the highest (198.93 kg x km(-2)) in summer and the lowest (42.35 kg x km(-2)) in spring. Of the 3 species groups, crabs had the highest stock density (41.81 kg x km(-2)), followed by shrimps (38.91 kg x km(-2)), and squills (18.88 kg x km(-2)). The stock densities of the 3 species groups showed an obvious seasonal variation. Shrimps had the highest stock density (120.32 kg x km(-2)) in summer and the lowest density (0.67 kg x km(-2)) in spring, while crabs and squills had the highest

  7. Intra-articular distribution pattern after ultrasound-guided injections in wrist joints of patients with rheumatoid arthritis

    DEFF Research Database (Denmark)

    Boesen, Mikael; Jensen, Karl Erik; Torp-Pedersen, Søren

    2007-01-01

    OBJECTIVE: To investigate the distribution of an ultrasound-guided intra-articular (IA) injection in the wrist joint of patients with rheumatoid arthritis (RA). METHODS: An ultrasound-guided IA drug injection into the wrist joint was performed in 17 patients with 1 ml methylprednisolone (40 mg....../ml), 0.5 ml Lidocaine (5mg/ml) and 0.15 ml gadolinium (Omniscan 0.5 mmol/ml). The drug solution was placed in the central proximal part of the wrist between the distal radius and the lunate bone. Coronal and axial MRI sequences were performed after the injection to visualize the distribution. Carpal...... with the MRI OMERACT synovitis score (r=0.60, p=0.014), but not with the erosions, bonemarrow oedema scores or any clinical parameters. CONCLUSION: The distribution of contrast on MRI showed patient specific and random patterns after IA injections in active RA wrist joints. The degree of distribution increased...

  8. Development of a pattern to measure multiscale deformation and strain distribution via in situ FE-SEM observations.

    Science.gov (United States)

    Tanaka, Y; Naito, K; Kishimoto, S; Kagawa, Y

    2011-03-18

    We investigated a method for measuring deformation and strain distribution in a multiscale range from nanometers to millimeters via in situ FE-SEM observations. A multiscale pattern composed of a grid as well as random and nanocluster patterns was developed to measure the localized deformation at the specimen surface. Our in situ observations of a carbon fiber-reinforced polymer matrix composite with a hierarchical microstructure subjected to loading were conducted to identify local deformation behaviors at various boundaries. We measured and analyzed the multiscale deformation and strain localizations during various stages of loading.

  9. Distribution patterns of Macrobrachium rosenbergii relative to the presence of cover strips

    Energy Technology Data Exchange (ETDEWEB)

    Vascotto, G.L.

    1987-05-27

    The responses of adult Macrobrachium rosenbergii to the presence, absence and location of artificial cover strips in four different configurations were studied in aquaria. The animals displayed a strong preference for the cover strips. When strips dangling from the surface were presented, the animals could be induced to occupy the upper half of the water column at densities nearly 4.5 times higher than in a bare tank. Strips extending from the surface to bottom also resulted in a significant redistribution of animals. The animals associated with cover strips tended to favor horizontal surfaces such as those found at the tips of strips and at the bottom. The success of cover in redistributing the prawns appeared to be negatively influenced by the presence of dominant males who maintained a number of smaller animals herded in the corners of the aquaria.

  10. Distribution patterns and feeding success of anchovy, Engraulis anchoita, larvae off southern Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo Cunha Vasconcellos

    1998-12-01

    Full Text Available Feeding success and changes in horizontal patchiness relative to size were studied for anchovy, Engraulis anchoita, larvae caught with a Bongo net off southern Brazil. Results show higher feeding success rates during winter, when the combined effect of enrichment, stability and retention mechanisms seems to create optimal conditions for larval feeding. Under optimal feeding conditions larvae of more than 10 mm have higher feeding success rates than smaller size classes. With a simple body structure and low swimming capabilities, larvae of up to 10 mm show a low level of patchiness, low evasion rate of the sampling gear and feeding on small food particles only. Results corroborate the hypothesis of a critical period between two important ontogenic phases: the beginning of exogenous feeding and the onset of active swimming, gas gland buoyancy and school forming behavior.

  11. HORIZONTAL BOILING REACTOR SYSTEM

    Science.gov (United States)

    Treshow, M.

    1958-11-18

    Reactors of the boiling water type are described wherein water serves both as the moderator and coolant. The reactor system consists essentially of a horizontal pressure vessel divided into two compartments by a weir, a thermal neutronic reactor core having vertical coolant passages and designed to use water as a moderator-coolant posltioned in one compartment, means for removing live steam from the other compartment and means for conveying feed-water and water from the steam compartment to the reactor compartment. The system further includes auxiliary apparatus to utilize the steam for driving a turbine and returning the condensate to the feed-water inlet of the reactor. The entire system is designed so that the reactor is self-regulating and has self-limiting power and self-limiting pressure features.

  12. Urodynamic pattern distribution among aged male patients with lower urinary tract symptoms suggestive of bladder outlet obstruction.

    Science.gov (United States)

    Xu, Danfeng; Cui, Xingang; Qu, Chuangyu; Yin, Lei; Wang, Cunzhou; Chen, Jie

    2014-03-01

    To develop a urodynamic study (UDS) pattern system for aged male patients who complained of non-neurogenic lower urinary tract symptoms (LUTS) to create a reference guideline for their diagnosis and treatment by a retrospective analysis. A retrospective analysis of UDS data was carried out in 1984 male patients neurologically intact with symptoms suggestive of bladder outlet obstruction (BOO) aged older than 45 years (2002-2013). On the basis of their UDS characteristic findings, the patients were classified into 1 of 7 subgroups: equivocal or mild BOO with sphincter synergia with or without idiopathic detrusor overactivity (pattern A); equivocal or mild BOO with idiopathic sphincter overactivity (B); classic BOO with sphincter synergia (C) or overactivity (D); BOO with only detrusor low compliance (E); BOO with both detrusor underactivity and low compliance (F); and equivocal BOO with detrusor underactivity (G). The follow-up data were reviewed and analyzed thereafter. The feasibility and rationality of this system were confirmed. The distribution of 7 patterns (pattern, case number, %) was A 158, 8%; B 59, 3%; C 1059, 53.3%; D 277, 14%; E 120, 6%; F 93, 4.7%; and G 218, 11%. A-G numbers in pattern C, D, and E were 103.1-141.4, higher than other patterns (P <.001), and functional pressure lengths of pattern C and D were 7.0-7.2 cm, longer than other patterns (P <.001). A practical UDS pattern system for aged male patients with lower urinary tract symptoms suggestive of BOO was constructed, which can be used to optimize the diagnosis and treatment of these patients. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Efecto de la estructuración por macrófitas y por recursos alimentarios en la distribución horizontal de tecamebas y rotíferos en un lago andino patagónico Effect of macrophytes and food resources on the horizontal distribution of testate amoebae and rotifers in an Andean-Patagonian lake

    Directory of Open Access Journals (Sweden)

    MARCELA BASTIDAS-NAVARRO

    2007-09-01

    con el aumento de la abundancia de la cianofita Coelosphaerium kuetzingianum. Las diferencias señaladas indican que los recursos alimentarios serían un factor determinante en la distribución de especies de tecamebas y rotíferos en el lago Escondido. Para estos zoopláncteres de pequeño tamaño las macrófitas litorales brindarían alimento al favorecer el incremento del fitoplancton de redThe presence of macrophytes in the littoral zone of lakes produces particular conditions including higher resource availability for consumers. For this reason, the littoral zone is generally the area with the highest diversity of lakes and rivers. In this work we studied the horizontal distribution of testate amoebae and rotifers in Lago Escondido (Argentina in relation to food resources availability. The study was carried out along a north-south transect that includes the littoral and the pelagic zone of the lake. Phytoplankton and zooplankton were sampled during summer and spring (2001-2003 in five sampling stations: one pelagic and four littoral. Rotifers and testate amoebae, as well as phytoplanktonic algae abundance and biomass were estimated. Food resources were classified as nanoplankton ( 20 μm and the biovolume of these fractions varied significantly within the pelagic and littoral zones of the lake. Nanoplankon dominated the pelagic zone and was mainly composed by nanoflagellates while net phytoplankton prevailed in the littoral zone and was composed by diatoms, cyanophytes and chlorophytes. The highest number of species and diversity of testate amoebae and rotifers were observed in the littoral stations; nevertheless, no significant differences between the zones colonized by different macrophytes were observed. The CCA analysis showed four different groups. Keratella cochlearis, Synchaeta spp., Polyarthra vulgaris and Collotheca mutabilis characterized the pelagic samples and were related with a high abundance of nanoplankton. On the other hand, rotifers like

  14. Expression of transcription activator ComK of Bacillus subtilis in the heterologous host Lactococcus lactis leads to a genome-wide repression pattern : a case study of horizontal gene transfer

    NARCIS (Netherlands)

    Susanna, K.A.; den Hengst, C.D.; Hamoen, L.W; Kuipers, O.P.

    Horizontal gene transfer (HGT) is generally considered a possible mechanism by which bacteria acquire new genetic properties. Especially when pathogenicity genes are involved, HGT might have important consequences for humans. In this report we describe a case study of HGT in which a transcriptional

  15. PRODUCTIVITY OF FRACTURED HORIZONTAL WELLS

    Directory of Open Access Journals (Sweden)

    Stjepan Antolović

    2009-12-01

    Full Text Available The interest and performance of horizontal drilling and completions has increased during the last two decades. Horizontal wells are advantageous compared to vertical wells in thin reservoirs, reservoirs with favorable vertical permeability and reservoirs with water and gas coning problems. In many reservoirs, the ratio of horizontal permeability to the vertical permeability is substantially larger than one and often is close to 10. Thus, these reservoirs are very good candidates for hydraulic fracturing. By hydraulic fracturing one or more fractures are created, which can be longitudinal or orthogonal. By that, flow is altered and it mostly conducts horizontally through reservoir toward horizontal wellbore. With this altered flow, fluid is produced faster, with less pressure loss by fluid unit of produced fluid. Some of the existing mathematical models to determine the productivity of multifractured horizontal wells are presented in this work (the paper is published in Croatian.

  16. Exact distribution of a pattern in a set of random sequences generated by a Markov source: applications to biological data

    Directory of Open Access Journals (Sweden)

    Regad Leslie

    2010-01-01

    Full Text Available Abstract Background In bioinformatics it is common to search for a pattern of interest in a potentially large set of rather short sequences (upstream gene regions, proteins, exons, etc.. Although many methodological approaches allow practitioners to compute the distribution of a pattern count in a random sequence generated by a Markov source, no specific developments have taken into account the counting of occurrences in a set of independent sequences. We aim to address this problem by deriving efficient approaches and algorithms to perform these computations both for low and high complexity patterns in the framework of homogeneous or heterogeneous Markov models. Results The latest advances in the field allowed us to use a technique of optimal Markov chain embedding based on deterministic finite automata to introduce three innovative algorithms. Algorithm 1 is the only one able to deal with heterogeneous models. It also permits to avoid any product of convolution of the pattern distribution in individual sequences. When working with homogeneous models, Algorithm 2 yields a dramatic reduction in the complexity by taking advantage of previous computations to obtain moment generating functions efficiently. In the particular case of low or moderate complexity patterns, Algorithm 3 exploits power computation and binary decomposition to further reduce the time complexity to a logarithmic scale. All these algorithms and their relative interest in comparison with existing ones were then tested and discussed on a toy-example and three biological data sets: structural patterns in protein loop structures, PROSITE signatures in a bacterial proteome, and transcription factors in upstream gene regions. On these data sets, we also compared our exact approaches to the tempting approximation that consists in concatenating the sequences in the data set into a single sequence. Conclusions Our algorithms prove to be effective and able to handle real data sets with

  17. Exact distribution of a pattern in a set of random sequences generated by a Markov source: applications to biological data

    Science.gov (United States)

    2010-01-01

    Background In bioinformatics it is common to search for a pattern of interest in a potentially large set of rather short sequences (upstream gene regions, proteins, exons, etc.). Although many methodological approaches allow practitioners to compute the distribution of a pattern count in a random sequence generated by a Markov source, no specific developments have taken into account the counting of occurrences in a set of independent sequences. We aim to address this problem by deriving efficient approaches and algorithms to perform these computations both for low and high complexity patterns in the framework of homogeneous or heterogeneous Markov models. Results The latest advances in the field allowed us to use a technique of optimal Markov chain embedding based on deterministic finite automata to introduce three innovative algorithms. Algorithm 1 is the only one able to deal with heterogeneous models. It also permits to avoid any product of convolution of the pattern distribution in individual sequences. When working with homogeneous models, Algorithm 2 yields a dramatic reduction in the complexity by taking advantage of previous computations to obtain moment generating functions efficiently. In the particular case of low or moderate complexity patterns, Algorithm 3 exploits power computation and binary decomposition to further reduce the time complexity to a logarithmic scale. All these algorithms and their relative interest in comparison with existing ones were then tested and discussed on a toy-example and three biological data sets: structural patterns in protein loop structures, PROSITE signatures in a bacterial proteome, and transcription factors in upstream gene regions. On these data sets, we also compared our exact approaches to the tempting approximation that consists in concatenating the sequences in the data set into a single sequence. Conclusions Our algorithms prove to be effective and able to handle real data sets with multiple sequences, as well

  18. Patterns in the Distribution of Digital Games via BitTorrent

    DEFF Research Database (Denmark)

    Drachen, Anders; Veitch, Rob

    2013-01-01

    The distribution of illegal copies of computer games via digital networks forms the centre in one of the most heated debates in the international games environment, but there is minimal objective information available. Here the results of a large-scale, open-method analysis of the distribution of...

  19. Patterns in the distribution of digital games via BitTorrent

    DEFF Research Database (Denmark)

    Drachen, Anders; Veitch, Robert W. D.

    2013-01-01

    The distribution of illegal copies of computer games via digital networks forms the centre in one of the most heated debates in the international games environment, but there is minimal objective information available. Here the results of a large-scale, open-method analysis of the distribution of...

  20. Temporal and spatial patterns in the distribution of squid Loligo spp ...

    African Journals Online (AJOL)

    A Geographic Information System (GIS) was used to test hypotheses regarding the spatial distribution of the squid Loligo forbesi and Loligo vulgaris vulgaris in the northern North-East Atlantic during the years 1989-1994. Loligo spp. were present throughout coastal waters of the United Kingdom, but distribution was patchy ...

  1. Effects of resource distribution patterns on ungulate foraging behaviour: a modelling approach.

    NARCIS (Netherlands)

    Wallis de Vries, M.F.

    1996-01-01

    The food resources of forest ungulates typically are patchily distributed. Research on foraging behaviour has often focused on habitat selection but has rarely taken into account the influence of the spatial distribution of different food patches in two dimensions. However, especially when

  2. Contrasting genetic diversity patterns in two sister kelp species co-distributed along the coast of Brittany, France.

    Science.gov (United States)

    Robuchon, Marine; Le Gall, Line; Mauger, Stéphane; Valero, Myriam

    2014-06-01

    We investigated patterns of genetic structure in two sister kelp species to explore how distribution width along the shore, zonation, latitudinal distribution and historical factors contribute to contrasting patterns of genetic diversity. We implemented a hierarchical sampling scheme to compare patterns of genetic diversity and structure in these two kelp species co-distributed along the coasts of Brittany (France) using a total of 12 microsatellites, nine for Laminaria hyperborea and 11 for Laminaria digitata, of which eight amplified in both species. The genetic diversity and connectivity of L. hyperborea populations were greater than those of L. digitata populations in accordance with the larger cross-shore distribution width along the coast and the greater depth occupied by L. hyperborea populations in contrast to L. digitata populations. In addition, marginal populations showed reduced genetic diversity and connectivity, which erased isolation-by-distance patterns in both species. As L. digitata encounters its southern range limit in southern Brittany (SBr) while L. hyperborea extends down to mid-Portugal, it was possible to distinguish the effect of habitat continuity from range edge effects. We found that L. digitata did not harbour high regional diversity at its southern edge, as expected in a typical rear edge, suggesting that refuges from the last glacial maximum for L. digitata were probably not located in SBr, but most likely further north. For both species, the highest levels of genetic diversity were found in the Iroise Sea and Morlaix Bay, the two regions in which they are being currently harvested. Preserving genetic diversity of these two foundation species in these areas should, thus, be a priority for the management of this resource in Brittany. © 2014 John Wiley & Sons Ltd.

  3. Rainfall interception and distribution patterns of gross precipitation around an isolated Ficus benjamina tree in an urban area

    Science.gov (United States)

    Guevara-Escobar, A.; González-Sosa, E.; Véliz-Chávez, C.; Ventura-Ramos, E.; Ramos-Salinas, M.

    2007-02-01

    SummaryInterception of rainfall by urban trees can be an important component of urban landscapes. This work evaluated rainfall interception and distribution patterns of gross precipitation around the canopy of a single evergreen tree Ficus benjamina (L.). Nineteen individual storms occurring from July to October, 2005, were analyzed. Total precipitation for the studied period was 152 mm representing 46% of the annual precipitation. Rainfall was partitioned as follows: 38.1% throughfall, 2.4% stemflow, and 59.5% interception by the tree canopy. Canopy saturation was estimated at 1.5 mm using a linear relationship between throughfall and stemflow. Average time for saturation of canopy was 19.5 min. The screen effect was important and accounted for 18.7% of the interception losses by the tree canopy alone. A kriging model was used to explore spatial distribution patterns of rainfall and the screen effect around the projected crown. The results indicated that the tree modifies the precipitation pattern around the tree and suggested that these patterns were similar among events.

  4. The Association between Land-Use Distribution and Residential Patterns: the Case of Mixed Arab-Jewish Cities in Israel

    Directory of Open Access Journals (Sweden)

    Ran GOLDBLATT

    2014-06-01

    Full Text Available The emergence of GIS and the availability of high resolution geographic data have improved our ability to investigate the residential segregation in cities and to identify the temporal changes of the spatial phenomena. Using GIS, we have quantitatively and visually analyzed the correspondence between land-use distribution and Arab residential patterns and their changes in the period between 1983 and 2008 in five mixed Arab-Jewish Israeli cities. Results show a correspondence between the dynamics of Arab/Jewish residential patterns and the spatial distribution of various land-uses. Arab residential patterns diffused faster towards areas with relatively inferior land-uses than towards areas with more attractive land-uses, in which a gentrification process occurred. Moreover, large-scale non-residential land-uses act as spatial partitions that divide between Arab and Jewish residential areas. Understanding the association between the urban environment and residential patterns can help in formulating an appropriate social and spatial policy concerning planning of land-uses and design of the built environment in mixed cities.

  5. Distribution pattern of picoplankton carbon biomass linked to mesoscale dynamics in the southern gulf of Mexico during winter conditions

    Science.gov (United States)

    Linacre, Lorena; Lara-Lara, Rubén; Camacho-Ibar, Víctor; Herguera, Juan Carlos; Bazán-Guzmán, Carmen; Ferreira-Bartrina, Vicente

    2015-12-01

    In order to characterize the carbon biomass spatial distribution of autotrophic and heterotrophic picoplankton populations linked to mesoscale dynamics, an investigation over an extensive open-ocean region of the southern Gulf of Mexico (GM) was conducted. Seawater samples from the mixed layer were collected during wintertime (February-March 2013). Picoplankton populations were counted and sorted using flow cytometry analyses. Carbon biomass was assessed based on in situ cell abundances and conversion factors from the literature. Approximately 46% of the total picoplankton biomass was composed of three autotrophic populations (Prochlorococcus, Synechococcus, and pico-eukaryotes), while 54% consisted of heterotrophic bacteria populations. Prochlorococcus spp. was the most abundant pico-primary producer (>80%), and accounted for more than 60% of the total pico-autotrophic biomass. The distribution patterns of picoplankton biomass were strongly associated with the mesoscale dynamics that modulated the hydrographic conditions of the surface mixed layer. The main features of the carbon distribution pattern were: (1) the deepening of picoplankton biomass to layers closer to the nitracline base in anticyclonic eddies; (2) the shoaling of picoplankton biomass in cyclonic eddies, constraining the autoprokaryote biomasses to the upper layers, as well as accumulating the pico-eukaryote biomass in the cold core of the eddies; and (3) the increase of heterotrophic bacteria biomass in frontal regions between counter-paired anticyclonic and cyclonic eddies. Factors related to nutrient preferences and light conditions may as well have contributed to the distribution pattern of the microbial populations. The findings reveal the great influence of the mesoscale dynamics on the distribution of picoplankton populations within the mixed layer. Moreover, the significance of microbial components (especially Prochlorococcus) in the southern GM during winter conditions was revealed

  6. Distribution patterns of chaetognata, polychaeta, pteropoda and salpidae off south georgia and south orkney islands

    Directory of Open Access Journals (Sweden)

    Alina María Crelier

    2010-12-01

    Full Text Available The distribution pattern, frequency and density (ind./1000 m of different mesozooplankton species from the South Georgia Islands, South Orkney Islands and the Weddell-Scotia Confluence were analyzed using data obtained in 1994. The maximum densities of the species found were: Eukrohnia hamata (5330, Sagitta gazellae (1052, Clione limacina antarctica (450, Spongiobranchaea australis (375, Clio sulcata (100, Limacina helicina (4076 x 10³, Limacina retroversa (71 x 10(4, Pelagobia longicirrata (29170, Rhynchonereella bongraini (117, Tomopteris carpenterii (26, Tomopteris planktonis (498, Tomopteris septentrionales (498 and Salpa thompsoni (189. Species density and frequency decreased from South Georgia to the South Orkney Islands, recording intermediate values at the Weddell-Scotia Confluence. Species density in the South Orkney area seemed to be limited by variations in temperature and salinity. The southern area around South Georgia showed the highest density of species, probably due to the influence of the Southern Front of the Antarctic Circumpolar Current. The presence of species characteristic of sub-Antarctic waters such as L. retroversa in the Confluence area could be related to the southward movements of eddies that originate in the Polar Front.Foram analisados os padrões de distribuição, freqüência e densidade (ind. 1000 m de diferentes espécies de mesozooplâncton encontradas em torno das ilhas Georgias e Orcadas del Sur no verão de 1994. As densidades máximas apresentadas pelas espécies principais foram: Eukrohnia hamata (5330, Sagitta gazellae (1052, Clione limacina antarctica (450, Spongiobranchaea australis (375, Clio sulcata (100, Limacina helicina (4076 x 10³, Limacina retroversa (71 x 10(4; Pelagobia longicirrata (29170, Rhynchonereella bongraini (117, Tomopteris carpenterii (26, Tomopteris planktonis (498, Tomopteris septentrionales (498 y Salpa thompsoni (189. A densidade e freqüência das espécies diminuíram das

  7. Spatial patterns of primary productivity derived from the Dynamic Habitat Indices predict patterns of species richness and distributions in the tropics

    Science.gov (United States)

    Suttidate, Naparat

    Humans are changing the Earth's ecosystems, which has profound consequences for biodiversity. To understand how species respond to these changes, biodiversity science requires accurate assessments of biodiversity. However, biodiversity assessments are still limited in tropical regions. The Dynamic Habitat Indices (DHIs), derived from satellite data, summarize dynamic patterns of annual primary productivity: (a) cumulative annual productivity, (b) minimum annual productivity, and (c) seasonal variation in productivity. The DHIs have been successfully used in temperate regions, but not yet in the tropics. My goal was to evaluate the importance of primary productivity measured via the DHIs for assessing patterns of species richness and distributions in Thailand. First, I assessed the relationships between the DHIs and tropical bird species richness. I also evaluated the complementarity of the DHIs and topography, climate, latitudinal gradients, habitat heterogeneity, and habitat area in explaining bird species richness. I found that among three DHIs, cumulative annual productivity was the most important factor in explaining bird species richness and that the DHIs outperformed other environmental variables. Second, I developed texture measures derive from DHI cumulative annual productivity, and compared them to habitat composition and fragmentation as predictors of tropical forest bird distributions. I found that adding texture measures to habitat composition and fragmentation models improved the prediction of tropical bird distributions, especially area- and edge-sensitive tropical forest bird species. Third, I predicted the effects of trophic interactions between primary productivity, prey, and predators in relation to habitat connectivity for Indochinese tigers (Panthera tigris). I found that including trophic interactions improved habitat suitability models for tigers. However, tiger habitat is highly fragmented with few dispersal corridors. I also identified

  8. Three-dimensional distribution of cortical synapses: a replicated point pattern-based analysis

    Science.gov (United States)

    Anton-Sanchez, Laura; Bielza, Concha; Merchán-Pérez, Angel; Rodríguez, José-Rodrigo; DeFelipe, Javier; Larrañaga, Pedro

    2014-01-01

    The biggest problem when analyzing the brain is that its synaptic connections are extremely complex. Generally, the billions of neurons making up the brain exchange information through two types of highly specialized structures: chemical synapses (the vast majority) and so-called gap junctions (a substrate of one class of electrical synapse). Here we are interested in exploring the three-dimensional spatial distribution of chemical synapses in the cerebral cortex. Recent research has showed that the three-dimensional spatial distribution of synapses in layer III of the neocortex can be modeled by a random sequential adsorption (RSA) point process, i.e., synapses are distributed in space almost randomly, with the only constraint that they cannot overlap. In this study we hypothesize that RSA processes can also explain the distribution of synapses in all cortical layers. We also investigate whether there are differences in both the synaptic density and spatial distribution of synapses between layers. Using combined focused ion beam milling and scanning electron microscopy (FIB/SEM), we obtained three-dimensional samples from the six layers of the rat somatosensory cortex and identified and reconstructed the synaptic junctions. A total volume of tissue of approximately 4500μm3 and around 4000 synapses from three different animals were analyzed. Different samples, layers and/or animals were aggregated and compared using RSA replicated spatial point processes. The results showed no significant differences in the synaptic distribution across the different rats used in the study. We found that RSA processes described the spatial distribution of synapses in all samples of each layer. We also found that the synaptic distribution in layers II to VI conforms to a common underlying RSA process with different densities per layer. Interestingly, the results showed that synapses in layer I had a slightly different spatial distribution from the other layers. PMID:25206325

  9. Post mortem CT of intrahepatic gas distribution in twenty-seven victims of a flood: Patterns and timing.

    Science.gov (United States)

    Sapienza, Daniela; Bottari, Antonio; Gualniera, Patrizia; Asmundo, Alessio; Perri, Fabrizio; Gaeta, Michele

    2017-09-21

    We reported the results of post mortem computed tomography of the liver in 27 subjects dead simultaneously during a flood. The aim of our work was to identify the different patterns of post mortem intrahepatic gas distribution and the timing of its appearance. Although post mortem CT is the method of choice for the evaluation of gas distribution, controversies exist about the first site of appearance of intrahepatic gas (portal veins versus hepatic veins) as well as the timing and steps of intrahepatic gas spreading. In each subject we performed thin slice CT scanner (Somatom Definition, Siemens) and post processing of native CT images with Minimum Intensity Projection technique. Our results show that the first site of appearance of intrahepatic gas is portal veins. Gas in hepatic veins was never seen without the presence of the gas in portal vein. Gaseous cysts in hepatic parenchyma represent a further and usually more tardive pattern of intrahepatic gas distribution. In addition, we demonstrated that differences in timing of gas spreading was statistically significative for exclusive presence of portal veins gas before 48h as well as for complete substitution of hepatic parenchyma by cysts 64h after death. In conclusion, our work shows that the CT study of postmortem intrahepatic gas distribution could be a useful complementary tool both in demonstrating the mechanism of intrahepatic gas spreading and in estimating post mortem interval. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Circular distribution pattern of plant modulars and endophagous herbivory within tree crowns: the impact of roadside light conditions.

    Science.gov (United States)

    Dai, Xiao-Hua; Xu, Jia-Sheng; Ding, Xing-Lu

    2013-01-01

    The circular distributions of plant modulars (branches, leaves) and endophagous herbivory (mines, galls) were investigated within the crowns of four dominant Fagaceae trees in a subtropical evergreen broadleaf forest at Jiulianshan National Nature Reserve, Jiangxi, China. The hypothesis is that more plant modulars and more endophagous herbivory should occur in the crown area perpendicular to the roads. Circular statistical techniques were used to verify new patterns of the impact of roads on plants and insects. The results confirmed that the roadside light environments had larger impacts on the circular distribution patterns of plant modulars than those of leaf herbivores. For herbivores, the impact of light was larger on mine distribution than on gall distribution. The branches of all four tree species were concentrated in the direction perpendicular to the roads. In the preferred direction, branches were longer and higher. More leaves, more mines, and more galls were found surrounding the preferred branch direction. In general, leaf miners and leaf gallers preferred leaves in the sun over those in the shade; however, leaf gallers had a lower degree of preference for sun than leaf miners. Different endphagous insects also showed clear interspecific differences in sun/shade leaf selection.

  11. Horizontal transfer of a plant transposon.

    Directory of Open Access Journals (Sweden)

    Xianmin Diao

    2006-01-01

    Full Text Available The majority of well-documented cases of horizontal transfer between higher eukaryotes involve the movement of transposable elements between animals. Surprisingly, although plant genomes often contain vast numbers of these mobile genetic elements, no evidence of horizontal transfer of a nuclear-encoded transposon between plant species has been detected to date. The most mutagenic known plant transposable element system is the Mutator system in maize. Mu-like elements (MULEs are widespread among plants, and previous analysis has suggested that the distribution of various subgroups of MULEs is patchy, consistent with horizontal transfer. We have sequenced portions of MULE transposons from a number of species of the genus Setaria and compared them to each other and to publicly available databases. A subset of these elements is remarkably similar to a small family of MULEs in rice. A comparison of noncoding and synonymous sequences revealed that the observed similarity is not due to selection at the amino acid level. Given the amount of time separating Setaria and rice, the degree of similarity between these elements excludes the possibility of simple vertical transmission of this class of MULEs. This is the first well-documented example of horizontal transfer of any nuclear-encoded genes between higher plants.

  12. Horizontal Transfer of a Plant Transposon.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available The majority of well-documented cases of horizontal transfer between higher eukaryotes involve the movement of transposable elements between animals. Surprisingly, although plant genomes often contain vast numbers of these mobile genetic elements, no evidence of horizontal transfer of a nuclear-encoded transposon between plant species has been detected to date. The most mutagenic known plant transposable element system is the Mutator system in maize. Mu-like elements (MULEs are widespread among plants, and previous analysis has suggested that the distribution of various subgroups of MULEs is patchy, consistent with horizontal transfer. We have sequenced portions of MULE transposons from a number of species of the genus Setaria and compared them to each other and to publicly available databases. A subset of these elements is remarkably similar to a small family of MULEs in rice. A comparison of noncoding and synonymous sequences revealed that the observed similarity is not due to selection at the amino acid level. Given the amount of time separating Setaria and rice, the degree of similarity between these elements excludes the possibility of simple vertical transmission of this class of MULEs. This is the first well-documented example of horizontal transfer of any nuclear-encoded genes between higher plants.

  13. Historical dynamics and current environmental effects explain the spatial distribution of species richness patterns of New World monkeys

    Directory of Open Access Journals (Sweden)

    Paulo Vallejos-Garrido

    2017-09-01

    Full Text Available Background Why biodiversity is not uniformly distributed on the Earth is a major research question of biogeography. One of the most striking patterns of disparity in species distribution are the biodiversity hotspots, which generally do not fit with the distribution of relevant components of the Neotropical biota. In this study, we assess the proximal causes of the species-richness pattern of one of the most conspicuous groups of Neotropical mammals, the New World monkeys the Platyrrhini. We test two complementary hypotheses: (1 there is a historical source-sink dynamic (addressed using macroevolutionary and macroecological approaches; (2 the large number of species in the Amazon basin is due to the constraints imposed by environmental variables occurring outside this area. Methods We first characterize spatial patterns of species richness and biodiversity hotspots using a new, objective protocol based on probabilities. Then we evaluate the source-sink hypothesis using BioGeoBEARS analysis and nestedness analysis of species richness patterns. Complementarily, to measure how often different species pairs appear in the same sites, we used null models to estimate the checkerboard score index (C-score. Finally, we evaluate the relationship between several climatic variables and species richness through ordinary least squares (OLS and spatial autoregressive (SAR models, and the potential environmental constraints on the pattern. Results We found one significant cluster of high values for species richness in the Amazon basin. Most dispersal events occurred from the Amazonian subregion to other Neotropical areas. Temperature (T, discrepancy (BR, and NODF indexes show a significant nesting in the matrix ordered by species richness and available energy. The C-score observed was significantly smaller than the null expectation for all sites in the Neotropics where there are records of platyrrhine species. Ten climatic variables comprised the best

  14. Distributional pattern of benthic foraminiferal morpho-groups in the shelf region off Mangalore: Environmental implications

    Digital Repository Service at National Institute of Oceanography (India)

    Khare, N.; Sinha, R.; Rai, A.K.; Nigam, R.

    , the population was further placed into two broad morpho-groups namely, angular-asymmetrical and rounded-symmetrical. The surficial distribution of these groups revealed that angular-asymmetrical forms are abundant in relatively deeper region whereas rounded...

  15. Intense Collaboration In Globally Distributed Teams: Evolving Patterns Of Dependencies And Coordination

    NARCIS (Netherlands)

    K. Kumar (Kuldeep); P.C. van Fenema (Paul); M.A. von Glinow

    2004-01-01

    textabstractAs multi-national firms and major offshore outsourcing companies develop experience with global work, their globally distributed teams face the challenge of collaborating intensely without the common interaction advantages associated with collocated work. This chapter analyzes the

  16. Distribution patterns of arbuscular mycorrhizal and non-mycorrhizal plant species in Germany

    Czech Academy of Sciences Publication Activity Database

    Menzel, A.; Hempel, S.; Manceur, A. M.; Götzenberger, Lars; Moora, M.; Rilling, M.C.; Zobel, M.; Kühn, I.

    2016-01-01

    Roč. 21, August 2016 (2016), s. 78-88 ISSN 1433-8319 Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * distribution model * Central Europe Subject RIV: EH - Ecology , Behaviour Impact factor: 3.123, year: 2016

  17. What can flux tracking teach us about water age distribution patterns and their temporal dynamics?

    NARCIS (Netherlands)

    Hrachowitz, M.; Savenije, H.; Bogaard, T.A.; Tetzlaff, D.; Soulsby, C.

    2013-01-01

    The complex interactions of runoff generation processes underlying the hydrological response of streams remain not entirely understood at the catchment scale. Extensive research has demonstrated the utility of tracers for both inferring flow path distributions and constraining model

  18. The Identity Mapping Project: Demographic differences in patterns of distributed identity.

    Science.gov (United States)

    Gilbert, Richard L; Dionisio, John David N; Forney, Andrew; Dorin, Philip

    2015-01-01

    The advent of cloud computing and a multi-platform digital environment is giving rise to a new phase of human identity called "The Distributed Self." In this conception, aspects of the self are distributed into a variety of 2D and 3D digital personas with the capacity to reflect any number of combinations of now malleable personality traits. In this way, the source of human identity remains internal and embodied, but the expression or enactment of the self becomes increasingly external, disembodied, and distributed on demand. The Identity Mapping Project (IMP) is an interdisciplinary collaboration between psychology and computer Science designed to empirically investigate the development of distributed forms of identity. Methodologically, it collects a large database of "identity maps" - computerized graphical representations of how active someone is online and how their identity is expressed and distributed across 7 core digital domains: email, blogs/personal websites, social networks, online forums, online dating sites, character based digital games, and virtual worlds. The current paper reports on gender and age differences in online identity based on an initial database of distributed identity profiles.

  19. Changes in wind pattern alter albatross distribution and life-history traits.

    Science.gov (United States)

    Weimerskirch, Henri; Louzao, Maite; de Grissac, Sophie; Delord, Karine

    2012-01-13

    Westerly winds in the Southern Ocean have increased in intensity and moved poleward. Using long-term demographic and foraging records, we show that foraging range in wandering albatrosses has shifted poleward in conjunction with these changes in wind pattern, while their rates of travel and flight speeds have increased. Consequently, the duration of foraging trips has decreased, breeding success has improved, and birds have increased in mass by more than 1 kilogram. These positive consequences of climate change may be temporary if patterns of wind in the southern westerlies follow predicted climate change scenarios. This study stresses the importance of foraging performance as the key link between environmental changes and population processes.

  20. Disjunct distributions of freshwater snails testify to a central role of the Congo system in shaping biogeographical patterns in Africa.

    Science.gov (United States)

    Schultheiß, Roland; Van Bocxlaer, Bert; Riedel, Frank; von Rintelen, Thomas; Albrecht, Christian

    2014-03-06

    The formation of the East African Rift System has decisively influenced the distribution and evolution of tropical Africa's biota by altering climate conditions, by creating basins for large long-lived lakes, and by affecting the catchment and drainage directions of river systems. However, it remains unclear how rifting affected the biogeographical patterns of freshwater biota through time on a continental scale, which is further complicated by the scarcity of molecular data from the largest African river system, the Congo. We study these biogeographical patterns using a fossil-calibrated multi-locus phylogeny of the gastropod family Viviparidae. This group allows reconstructing drainage patterns exceptionally well because it disperses very poorly in the absence of existing freshwater connections. Our phylogeny covers localities from major drainage basins of tropical Africa and reveals highly disjunct sister-group relationships between (a) the endemic viviparids of Lake Malawi and populations from the Middle Congo as well as between (b) the Victoria region and the Okavango/Upper Zambezi area. The current study testifies to repeated disruptions of the distribution of the Viviparidae during the formation of the East African Rift System, and to a central role of the Congo River system for the distribution of the continent's freshwater fauna during the late Cenozoic. By integrating our results with previous findings on palaeohydrographical connections, we provide a spatially and temporarily explicit model of historical freshwater biogeography in tropical Africa. Finally, we review similarities and differences in patterns of vertebrate and invertebrate dispersal. Amongst others we argue that the closest relatives of present day viviparids in Lake Malawi are living in the Middle Congo River, thus shedding new light on the origin of the endemic fauna of this rift lake.

  1. Fluid flow analysis in horizontal continuous casting tundish

    Science.gov (United States)

    Kam, Dong Heon; Lee, Hwang Ku; Han, Jeong Whan; You, Byung Don

    2002-11-01

    Water model studies were carried out to analyze fluid flow characteristics in a horizontal continuous casting tundish. The effects of LSN (ladle submerged nozzle) and dams on the flow pattems in a tundish were investigated and casting speeds were also changed as experimental parameters. Dye injection experiments were made to observe qualitative flow patterns and mixing characteristics in a continuous flowing tundish. And quantitative analyses of RTD (residence time distribution) curves using tracer pulse injection were also made to calculate the dead volume fraction in the water model tundish under consideration. From the results it was found that flow modification devices with an open stream have little effect on the flow patterns in the tundish, whether the dam is installed or not. This was confirmed by the flow visualization method showing upward flow near falling stream driven by the buoyancy force caused by air entrapment during liquid falling. However when LSN was installed between a ladle and a tundish there was a great change in flow pattern and a bypassing flow that existed in bare tundish was decreased with the use of dams. Especially, dead volume fraction was decreased with the increase of dam height.

  2. Effect of land use patterns on stability and distributions of organic ...

    African Journals Online (AJOL)

    Soil aggregation is important for the resistance of land surfaces to erosion, and it influences the ability of soils to remain productive. At the same time, it is also an important process of carbon sequestration. The objectives of this study were to elucidate the effects of different land use patterns on soil aggregate stability and the ...

  3. Frequency Distribution in Domestic Microwave Ovens and Its Influence on Heating Pattern.

    Science.gov (United States)

    Luan, Donglei; Wang, Yifen; Tang, Juming; Jain, Deepali

    2017-02-01

    In this study, snapshots of operating frequency profiles of domestic microwave ovens were collected to reveal the extent of microwave frequency variations under different operation conditions. A computer simulation model was developed based on the finite difference time domain method to analyze the influence of the shifting frequency on heating patterns of foods in a microwave oven. The results showed that the operating frequencies of empty and loaded domestic microwave ovens varied widely even among ovens of the same model purchased on the same date. Each microwave oven had its unique characteristic operating frequencies, which were also affected by the location and shape of the load. The simulated heating patterns of a gellan gel model food when heated on a rotary plate agreed well with the experimental results, which supported the reliability of the developed simulation model. Simulation indicated that the heating patterns of a stationary model food load changed with the varying operating frequency. However, the heating pattern of a rotary model food load was not sensitive to microwave frequencies due to the severe edge heating overshadowing the effects of the frequency variations. © 2016 Institute of Food Technologists®.

  4. Coccolith distribution patterns in South Atlantic and Southern Ocean surface sediments in relation to environmental gradients

    DEFF Research Database (Denmark)

    Boeckel, B.; Baumann, K.-H.; Henrich, R.

    2006-01-01

    In this study, the coccolith compositions of 213 surface sediment samples from the South Atlantic and Southern Ocean were analysed with respect to the environmental parameters of the overlying surface waters. From this data set, the abundance patterns of the main species and their ecological affi...

  5. Spatial and seasonal distribution patterns of the ragged-tooth shark ...

    African Journals Online (AJOL)

    Catches from competitive shore-anglers, inshore boatbased anglers and sightings by spearfishers and divers were used to infer the spatial and seasonal movement patterns of young-of-the-year (2.4m TL) ragged-tooth sharks Carcharias taurus along ...

  6. (TG/CAn repeats in human gene families: abundance and selective patterns of distribution according to function and gene length

    Directory of Open Access Journals (Sweden)

    Ramachandran Srinivasan

    2005-06-01

    Full Text Available Abstract Background Creation of human gene families was facilitated significantly by gene duplication and diversification. The (TG/CAn repeats exhibit length variability, display genome-wide distribution, and are abundant in the human genome. Accumulation of evidences for their multiple functional roles including regulation of transcription and stimulation of recombination and splicing elect them as functional elements. Here, we report analysis of the distribution of (TG/CAn repeats in human gene families. Results The 1,317 human gene families were classified into six functional classes. Distribution of (TG/CAn repeats were analyzed both from a global perspective and from a stratified perspective based on their biological properties. The number of genes with repeats decreased with increasing repeat length and several genes (53% had repeats of multiple types in various combinations. Repeats were positively associated with the class of Signaling and communication whereas, they were negatively associated with the classes of Immune and related functions and of Information. The proportion of genes with (TG/CAn repeats in each class was proportional to the corresponding average gene length. The repeat distribution pattern in large gene families generally mirrored the global distribution pattern but differed particularly for Collagen gene family, which was rich in repeats. The position and flanking sequences of the repeats of Collagen genes showed high conservation in the Chimpanzee genome. However the majority of these repeats displayed length polymorphism. Conclusion Positive association of repeats with genes of Signaling and communication points to their role in modulation of transcription. Negative association of repeats in genes of Information relates to the smaller gene length, higher expression and fundamental role in cellular physiology. In genes of Immune and related functions negative association of repeats perhaps relates to the smaller gene

  7. Geographic location, network patterns and population distribution of rural settlements in Greece

    Science.gov (United States)

    Asimakopoulos, Avraam; Mogios, Emmanuel; Xenikos, Dimitrios G.

    2016-10-01

    Our work addresses the problem of how social networks are embedded in space, by studying the spread of human population over complex geomorphological terrain. We focus on villages or small cities up to a few thousand inhabitants located in mountainous areas in Greece. This terrain presents a familiar tree-like structure of valleys and land plateaus. Cities are found more often at lower altitudes and exhibit preference on south orientation. Furthermore, the population generally avoids flat land plateaus and river beds, preferring locations slightly uphill, away from the plateau edge. Despite the location diversity regarding geomorphological parameters, we find certain quantitative norms when we examine location and population distributions relative to the (man-made) transportation network. In particular, settlements at radial distance ℓ away from road network junctions have the same mean altitude, practically independent of ℓ ranging from a few meters to 10 km. Similarly, the distribution of the settlement population at any given ℓ is the same for all ℓ. Finally, the cumulative distribution of the number of rural cities n(ℓ) is fitted to the Weibull distribution, suggesting that human decisions for creating settlements could be paralleled to mechanisms typically attributed to this particular statistical distribution.

  8. Distribution patterns of elements in dental enamel of G. blacki: a preliminary dietary investigation using SRXRF

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Yating; Hu, Yaowu; Shang, Xue; Wang, Changsui [Chinese Academy of Sciences, Lab of Human Evolution, Institute of Vertebrate Paleontology and Paleoanthropology, Beijing (China); University of Chinese Academy of Sciences, Department of Scientific History and Archaeometry, School of Humanities, Beijing (China); Jin, Changzhu; Zhang, Yingqi [Chinese Academy of Sciences, Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Beijing (China)

    2013-04-15

    We measured the elemental mappings in dental enamel of Gigantopithecus blacki (n=3) using synchrotron radiation X-ray fluorescence (SRXRF) to understand the dietary variation during the time of tooth eruption. In order to account for the effects of diagenesis on the variation of elements in these fossil teeth, we compared the Fe and Mn elemental distribution and levels in dental enamel of G. blacki with that of a single modern pig tooth and found no differences. The observation of the variations of Sr, Ca and RE (rare earth elements) distribution in the incremental lines reveals that the plant foods utilized by G. blacki from the early Pleistocene or the middle Pleistocene had varied during the formation of dental enamel, possibly caused by the change of living environment or food resources. The variations of elemental distribution in different incremental lines are very promising to understand the nutritional and physical stress of G. blacki during the tooth eruption and environmental adaptations. (orig.)

  9. Patterns of Failure After Proton Therapy in Medulloblastoma; Linear Energy Transfer Distributions and Relative Biological Effectiveness Associations for Relapses

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, Roshan V. [Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (United States); Giantsoudi, Drosoula; Raiford, Michael; Malhi, Imran; Niemierko, Andrzej [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Rapalino, Otto; Caruso, Paul [Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts (United States); Yock, Torunn I.; Tarbell, Nancy J.; Paganetti, Harald [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); MacDonald, Shannon M., E-mail: smacdonald@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2014-03-01

    Purpose: The pattern of failure in medulloblastoma patients treated with proton radiation therapy is unknown. For this increasingly used modality, it is important to ensure that outcomes are comparable to those in modern photon series. It has been suggested this pattern may differ from photons because of variations in linear energy transfer (LET) and relative biological effectiveness (RBE). In addition, the use of matching fields for delivery of craniospinal irradiation (CSI) may influence patterns of relapse. Here we report the patterns of failure after the use of protons, compare it to that in the available photon literature, and determine the LET and RBE values in areas of recurrence. Methods and Materials: Retrospective review of patients with medulloblastoma treated with proton radiation therapy at Massachusetts General Hospital (MGH) between 2002 and 2011. We documented the locations of first relapse. Discrete failures were contoured on the original planning computed tomography scan. Monte Carlo calculation methods were used to estimate the proton LET distribution. Models were used to estimate RBE values based on the LET distributions. Results: A total of 109 patients were followed for a median of 38.8 months (range, 1.4-119.2 months). Of the patients, 16 experienced relapse. Relapse involved the supratentorial compartment (n=8), spinal compartment (n=11), and posterior fossa (n=5). Eleven failures were isolated to a single compartment; 6 failures in the spine, 4 failures in the supratentorium, and 1 failure in the posterior fossa. The remaining patients had multiple sites of disease. One isolated spinal failure occurred at the spinal junction of 2 fields. None of the 70 patients treated with an involved-field-only boost failed in the posterior fossa outside of the tumor bed. We found no correlation between Monte Carlo-calculated LET distribution and regions of recurrence. Conclusions: The most common site of failure in patients treated with protons for

  10. Analysis of Road Network Pattern Considering Population Distribution and Central Business District.

    Directory of Open Access Journals (Sweden)

    Fangxia Zhao

    Full Text Available This paper proposes a road network growing model with the consideration of population distribution and central business district (CBD attraction. In the model, the relative neighborhood graph (RNG is introduced as the connection mechanism to capture the characteristics of road network topology. The simulation experiment is set up to illustrate the effects of population distribution and CBD attraction on the characteristics of road network. Moreover, several topological attributes of road network is evaluated by using coverage, circuitness, treeness and total length in the experiment. Finally, the suggested model is verified in the simulation of China and Beijing Highway networks.

  11. Patterns in the spatial distribution of Peruvian anchovy ( Engraulis ringens) revealed by spatially explicit fishing data

    Science.gov (United States)

    Bertrand, Sophie; Díaz, Erich; Lengaigne, Matthieu

    2008-10-01

    Peruvian anchovy ( Engraulis ringens) stock abundance is tightly driven by the high and unpredictable variability of the Humboldt Current Ecosystem. Management of the fishery therefore cannot rely on mid- or long-term management policy alone but needs to be adaptive at relatively short time scales. Regular acoustic surveys are performed on the stock at intervals of 2 to 4 times a year, but there is a need for more time continuous monitoring indicators to ensure that management can respond at suitable time scales. Existing literature suggests that spatially explicit data on the location of fishing activities could be used as a proxy for target stock distribution. Spatially explicit commercial fishing data could therefore guide adaptive management decisions at shorter time scales than is possible through scientific stock surveys. In this study we therefore aim to (1) estimate the position of fishing operations for the entire fleet of Peruvian anchovy purse-seiners using the Peruvian satellite vessel monitoring system (VMS), and (2) quantify the extent to which the distribution of purse-seine sets describes anchovy distribution. To estimate fishing set positions from vessel tracks derived from VMS data we developed a methodology based on artificial neural networks (ANN) trained on a sample of fishing trips with known fishing set positions (exact fishing positions are known for approximately 1.5% of the fleet from an at-sea observer program). The ANN correctly identified 83% of the real fishing sets and largely outperformed comparative linear models. This network is then used to forecast fishing operations for those trips where no observers were onboard. To quantify the extent to which fishing set distribution was correlated to stock distribution we compared three metrics describing features of the distributions (the mean distance to the coast, the total area of distribution, and a clustering index) for concomitant acoustic survey observations and fishing set positions

  12. Analysis of Road Network Pattern Considering Population Distribution and Central Business District.

    Science.gov (United States)

    Zhao, Fangxia; Sun, Huijun; Wu, Jianjun; Gao, Ziyou; Liu, Ronghui

    2016-01-01

    This paper proposes a road network growing model with the consideration of population distribution and central business district (CBD) attraction. In the model, the relative neighborhood graph (RNG) is introduced as the connection mechanism to capture the characteristics of road network topology. The simulation experiment is set up to illustrate the effects of population distribution and CBD attraction on the characteristics of road network. Moreover, several topological attributes of road network is evaluated by using coverage, circuitness, treeness and total length in the experiment. Finally, the suggested model is verified in the simulation of China and Beijing Highway networks.

  13. Environmental, land cover and land use constraints on the distributional patterns of anurans: Leptodacylus species (Anura, Leptodactylidae from Dry Chaco

    Directory of Open Access Journals (Sweden)

    Regina Gabriela Medina

    2016-11-01

    Full Text Available Subtropical dry forests are among the most vulnerable biomes to land transformation at a global scale. Among them, the Dry Chaco suffers an accelerated change due to agriculture expansion and intensification. The Dry Chaco ecoregion is characterized by high levels of endemisms and species diversity, which are the result of a variety of climates and reliefs, allowing a wide variety of environments. The amphibian group exhibits a high richness in the Dry Chaco, which has been barely studied in relation to land cover changes. We used ecological niche models (ENMs to assess the potential geographic distribution of 10 Leptodactylus species (Anura, Leptodactylidae, which are mainly distributed within the Dry Chaco. We characterized these distributions environmentally, analyzed their overlap with land cover classes, and assessed their diversity of ecoregions. Also, we evaluated how these species potential distribution is affected by the transformation of land, and quantified the proportional area of the potential distribution in protected areas. We found that temperature seasonality is the main constraint to the occurrence of the species studied, whose main habitats are savannas, grasslands and croplands. The main threats to these species are the effects of climate change over spatial patterns of seasonality, which could affect their breeding and reproduction mode; the loss of their natural habitat; the exposure to contaminants used by intensive agriculture and their underrepresentation in protected areas.

  14. Patterns of spatial and temporal distribution of humpback whales at the southern limit of the Southeast Pacific breeding area.

    Science.gov (United States)

    Guidino, Chiara; Llapapasca, Miguel A; Silva, Sebastian; Alcorta, Belen; Pacheco, Aldo S

    2014-01-01

    Understanding the patterns of spatial and temporal distribution in threshold habitats of highly migratory and endangered species is important for understanding their habitat requirements and recovery trends. Herein, we present new data about the distribution of humpback whales (Megaptera novaeangliae) in neritic waters off the northern coast of Peru: an area that constitutes a transitional path from cold, upwelling waters to warm equatorial waters where the breeding habitat is located. Data was collected during four consecutive austral winter/spring seasons from 2010 to 2013, using whale-watching boats as platforms for research. A total of 1048 whales distributed between 487 groups were sighted. The spatial distribution of humpbacks resembled the characteristic segregation of whale groups according to their size/age class and social context in breeding habitats; mother and calf pairs were present in very shallow waters close to the coast, while dyads, trios or more whales were widely distributed from shallow to moderate depths over the continental shelf break. Sea surface temperatures (range: 18.2-25.9°C) in coastal waters were slightly colder than those closer to the oceanic realm, likely due to the influence of cold upwelled waters from the Humboldt Current system. Our results provide new evidence of the southward extension of the breeding region of humpback whales in the Southeast Pacific. Integrating this information with the knowledge from the rest of the breeding region and foraging grounds would enhance our current understanding of population dynamics and recovery trends of this species.

  15. Patterns of spatial and temporal distribution of humpback whales at the southern limit of the Southeast Pacific breeding area.

    Directory of Open Access Journals (Sweden)

    Chiara Guidino

    Full Text Available Understanding the patterns of spatial and temporal distribution in threshold habitats of highly migratory and endangered species is important for understanding their habitat requirements and recovery trends. Herein, we present new data about the distribution of humpback whales (Megaptera novaeangliae in neritic waters off the northern coast of Peru: an area that constitutes a transitional path from cold, upwelling waters to warm equatorial waters where the breeding habitat is located. Data was collected during four consecutive austral winter/spring seasons from 2010 to 2013, using whale-watching boats as platforms for research. A total of 1048 whales distributed between 487 groups were sighted. The spatial distribution of humpbacks resembled the characteristic segregation of whale groups according to their size/age class and social context in breeding habitats; mother and calf pairs were present in very shallow waters close to the coast, while dyads, trios or more whales were widely distributed from shallow to moderate depths over the continental shelf break. Sea surface temperatures (range: 18.2-25.9°C in coastal waters were slightly colder than those closer to the oceanic realm, likely due to the influence of cold upwelled waters from the Humboldt Current system. Our results provide new evidence of the southward extension of the breeding region of humpback whales in the Southeast Pacific. Integrating this information with the knowledge from the rest of the breeding region and foraging grounds would enhance our current understanding of population dynamics and recovery trends of this species.

  16. A study of distribution, sex differences and stability of lip print patterns in an Indian population

    Directory of Open Access Journals (Sweden)

    Neeti Kapoor

    2017-09-01

    Type I (30.63% was found to be most predominant overall in the Marathi population. Type I (29.75% and Type III (35.75% were found most prevalent in males and females respectively. Applying the Chi-Square test, statistically significant differences (p < 0.05 were observed between male and female lip print patterns in each of the quadrants individually and all quadrants taken together. The lip print patterns remained stable over a period of six-months. Being stable and with significant sex differences, lip prints can be effectively used as an important tool in forensic investigations for individualization as well as identification of sex of the donor, thus, narrowing down the scope of investigation to almost half.

  17. [Spatiotemporal distribution of air temperature and precipitation in rice growth period in Fujian Province of East China and the effects of this distribution on rice planting pattern].

    Science.gov (United States)

    Jiang, Min; Jin, Zhi-Qing; Yang, Hui; Shi, Chun-Lin; Zhu, Chao-Zhi; Lin, Wen-Xiong

    2012-12-01

    In order to investigate the effects of climate change on the rice production and rice planting pattern in Fujian Province, an analysis was made on the spatiotemporal distribution of air temperature and precipitation in rice growth period in the Province, and the possible changes of the local rice planting pattern in the future, based on the A2, B2, and A1 B scenarios of IPCC Special Report on Emission Scenario (SRES). In the future, the rice growth period's air temperature in the Province tended to be increased, and the increment would be increased with time, with the maximum for single cropping rice and being 0.3-2.4 degrees C and 1.5-3.4 degrees C in 2011-2030 and 2031 -2050, respectively. For early rice and late rice, the increment of their growth period's air temperature would be 0.2-0.9 degrees C and 0.7-1.7 degrees C in 2011-2030 and 0.3-2.1 degrees C and 0.5-3.6 degrees C in 2031-2050, respectively, but the annual fluctuation of the mean daily temperature would be most obvious for late rice. The rice growth period's precipitation in most parts of the Province also tended to be increased, and the increment for early rice, single cropping rice, and late rice would be 10%-40%, 10%-30%, and 10%-20%, respectively. The annual fluctuation of the precipitation would be most obvious for the early rice in southeastern Fujian. The elevated air temperature in the future could induce the increase of > or = 10 degrees C accumulated temperature, and lengthen the rice growth season, making it possible to replace early and medium-maturity varieties with late-maturity varieties, and to adopt double-rice planting pattern instead of single-rice planting pattern.

  18. Distribution patterns, dermatomal anesthesia, and Ropivacaine serum concentrations after bilateral dualtransversus abdominis plane block

    DEFF Research Database (Denmark)

    Johansen, Sys Stybe

    2012-01-01

    The ability of transversus abdominis plane (TAP) blocks to anesthetize the upper abdomen remains debatable. We aimed to describe the local anesthetic distribution following ultrasound-guided TAP blocks with repeated magnetic resonance imaging investigations and to relate this to the resulting...

  19. Potential impacts of climate change on the distributions and diversity patterns of European mammals

    DEFF Research Database (Denmark)

    Lewinsky, Irina; Skov, Flemming; Svenning, J.-C.

    2007-01-01

    The Intergovernmental Panel on Climate Change (IPCC) predicts an increase in global temperatures of between 1.4°C and 5.8°C during the 21st century, as a result of elevated CO2 levels. Using bioclimatic envelope models, we evaluate the potential impact of climate change on the distributions and s...

  20. A spatial pattern analysis of the halophytic species distribution in an arid coastal environment.

    Science.gov (United States)

    Badreldin, Nasem; Uria-Diez, J; Mateu, J; Youssef, Ali; Stal, Cornelis; El-Bana, Magdy; Magdy, Ahmed; Goossens, Rudi

    2015-05-01

    Obtaining information about the spatial distribution of desert plants is considered as a serious challenge for ecologists and environmental modeling due to the required intensive field work and infrastructures in harsh and remote arid environments. A new method was applied for assessing the spatial distribution of the halophytic species (HS) in an arid coastal environment. This method was based on the object-based image analysis for a high-resolution Google Earth satellite image. The integration of the image processing techniques and field work provided accurate information about the spatial distribution of HS. The extracted objects were based on assumptions that explained the plant-pixel relationship. Three different types of digital image processing techniques were implemented and validated to obtain an accurate HS spatial distribution. A total of 2703 individuals of the HS community were found in the case study, and approximately 82% were located above an elevation of 2 m. The micro-topography exhibited a significant negative relationship with pH and EC (r = -0.79 and -0.81, respectively, p processes, in particular a hybrid family of Gibbs processes. A new model is proposed that uses a hard-core structure at very short distances, together with a cluster structure in short-to-medium distances and a Poisson structure for larger distances. This model was found to fit the data perfectly well.

  1. Dietary protein intake and distribution patterns of well-trained Dutch athletes

    NARCIS (Netherlands)

    Gillen, Jenna B.; Trommelen, Jorn; Wardenaar, Floris C.; Brinkmans, Naomi Y.J.; Versteegen, Joline J.; Jonvik, Kristin L.; Kapp, Christoph; Vries, de Jeanne; Borne, van den Joost J.G.C.; Gibala, Martin J.; Loon, van Luc J.C.

    2017-01-01

    Dietary protein intake should be optimized in all athletes to ensure proper recovery and enhance the skeletal muscle adaptive response to exercise training. In addition to total protein intake, the use of specific proteincontaining food sources and the distribution of protein throughout the day

  2. Influence of Off-Take Angles on Flow Distribution Pattern at Concave ...

    African Journals Online (AJOL)

    ... investigate the effect of off-take angles on the flow distribution at a concave channel bifurcation. Seven different off-take angles with varied main channel flow rates were used for the study. Predicting equations for the off-take discharge dependent on the off-take angles, main channel discharges, dispersion coefficients and ...

  3. Benthic Crustacea and Mollusca distribution in Arctic fjord – case study of patterns in Hornsund, Svalbard

    Directory of Open Access Journals (Sweden)

    Anna Drewnik

    2017-10-01

    Full Text Available We present the results of species distribution modeling conducted on macrobenthic occurrence data collected between 2002 and 2014 in Arctic fjord – Hornsund. We focus on species from Mollusca and Crustacea taxa. This study investigates the importance of individual environmental factors for benthic species distribution, with a special emphasis on bottom water temperature. It aims to verify the hypothesis that the distribution of species is controlled by low water temperatures in the fjord and that the inner basins of the fjord serve as potential refugia for Arctic species threatened by the climate change-related intensification of warmer water inflows. Our results confirm the importance of bottom water temperature in regulating the presence of benthic fauna in the Hornsund fjord. The distribution of studied species is clearly related to specific water mass – colder (1°C; and the preferred temperature regimes seem to be species specific and unrelated to analyzed groups. This study supports the notion that inner basins of the Hornsund fjord are potential refugia for cold water Arctic fauna, while the outer and central basins provide suitable habitats for fauna that prefer warmer waters.

  4. MVC Design Pattern for the multi framework distributed applications using XML, spring and struts framework

    OpenAIRE

    Praveen Gupta,; Prof. M.C. Govil

    2010-01-01

    The model view controller (MVC) is a fundamental design pattern for the separation between user interface logic and business logic. Since applications are very large in size these days and the MVC designpattern can weak the coupling among the different application tiers of application. this paper presents a web application framework based on MVC in J2EE platform, and extends it with XML so that the framework is more flexible, expansible and easy to maintain. This is a multi tier system includ...

  5. Habitual sleep patterns and the distribution of body mass index: cross-sectional findings among Swedish men and women.

    Science.gov (United States)

    Westerlund, Anna; Bottai, Matteo; Adami, Hans-Olov; Bellocco, Rino; Nyrén, Olof; Åkerstedt, Torbjörn; Lagerros, Ylva Trolle

    2014-10-01

    To compare distributions of body mass index (BMI) between individuals with different habitual sleep patterns. We performed cross-sectional analyses of 40,197 Swedish adults (64% women), who reported sleep duration and quality, weight, height, and possible confounding factors in 1997. Using quantile regression, we estimated associations between sleep patterns and selected percentiles of the distribution of BMI. While the medians were similar, larger adjusted values of BMI were estimated in the upper part of the distribution among men and women with short sleep (≤5 h) compared with medium-length sleep (6-8 h). For example, in men, the 90th percentile of BMI was 0.80 kg/m(2) (95% confidence interval: 0.17-1.43 kg/m(2)) higher among short sleepers. In women, long sleepers (≥9 h) also showed larger values in the upper part of the BMI distribution; the 90th percentile was 1.23 kg/m(2) (0.42-2.04 kg/m(2)) higher than in medium-length sleepers. In male long sleepers, smaller values were estimated in the lower part of the BMI distribution; the 10th percentile was 0.84 kg/m(2) lower (0.35-1.32 kg/m(2)) than in medium-length sleepers. The 90th percentile of BMI in women with poor-quality compared with good-quality sleep was larger by 0.82 kg/m(2) (0.47-1.16 kg/m(2)); the 10th percentile was smaller by 0.17 kg/m(2) (0.02-0.32 kg/m(2)). Short, long or poor-quality sleepers showed larger, or smaller, values at the tails of the BMI distribution, but similar medians. Hence, unfavorable sleep patterns and BMI were associated only in a subset of this study population. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Nucleic acid distribution pattern in avian erythrocytes and mammalian lymphocytes: comparative studies by fluorescence microscopy and digital imaging analytical techniques.

    Science.gov (United States)

    Isitor, G N; Asgarali, Z; Pouching, K

    2008-12-01

    Nucleated erythrocytes of healthy domestic chicken and ducks, and lymphocytes of healthy Sprague Dawley rats were evaluated for nucleic acid distribution pattern, employing light and fluorescence microscopy procedures, as well as digital imaging analytical methods. The results demonstrate a unique organization of nuclear DNA of mature chicken and duck erythrocytes, as well as immature duck erythrocytes, as delineated spherical nuclear bodies that mostly corresponded with euchromatin zones of the cells in routine Wright-stain blood smears. The nuclear DNA of the rat lymphocytes, on the other hand, was observed as a more diffuse green fluorescing nuclear areas, with punctate variably-sized diffuse areas of RNA red fluorescence. RNA red color fluorescence was also evident in the narrow cytoplasm of the lymphocytes, especially in large lymphocytes, in comparison with the cytoplasm of the mature avian erythrocytes that completely lacked any nucleic acid fluorescence. Nuclear RNA fluorescence was lacking in the mature chicken erythrocytes, compared with those of the mature and immature duck erythrocytes as well as lymphocytes of both avian and rats blood. The significance of these findings lies in the establishment of normal benchmarks for the nuclear and cytoplasmic nucleic acid pattern in eukaryotic cells. These normal benchmarks become valuable in rapid diagnostic situations associated with pathologies, such as the presence of viral nuclear and cytoplasmic inclusion bodies that can alter the nucleic acid pattern of the host cells, and in conditions of cellular abnormal protein aggregations. Variability of cellular nucleic acid pattern can also aid in prognostic assessments of neoplastic conditions.

  7. Spatial distribution patterns of terrestrial bird assemblages on islands of the Sabana–Camagüey Archipelago, Cuba: evaluating nestedness and co–occurrence patterns

    Directory of Open Access Journals (Sweden)

    Mancina, C. A.

    2013-12-01

    Full Text Available Using distribution data of 131 terrestrial bird species on 17 islands of the Archipelago Sabana–Camagüey, Cuba, we tested for non–randomness in presence–absence matrices with respect to co–occurrence and nestedness. We conducted separate analyses for the whole assemblage and sub–matrices according to trophic levels and residence status (breeding and migratory. We also explored the influence of weighting factors such as island area and isolation. The C–occurrence analyses were susceptible to the species subsets and the weighting factors. Unweighted analyses revealed a significant negative co–occurrence pattern for the entire assemblage and for most sub–matrices. The area weighted analyses always indicated strong non–random structure. However, an analysis with intra–guild species pairs showed that most pairs were randomly assembled; very few pairs had a significant segregated pattern. Bird assemblages followed a nested subset structure across islands. Nestedness was strongly correlated with area and unrelated with island isolation. Overall, this study suggests that terrestrial bird assemblages were shaped by extinction processes mediated through area effects rather than interspecific trophic guild competition. Data suggest that conservation of largest islands will guarantee high terrestrial bird richness on the archipelago.

  8. Computation of antenna pattern correlation and MIMO performance by means of surface current distribution and spherical wave theory

    Directory of Open Access Journals (Sweden)

    O. Klemp

    2006-01-01

    Full Text Available In order to satisfy the stringent demand for an accurate prediction of MIMO channel capacity and diversity performance in wireless communications, more effective and suitable models that account for real antenna radiation behavior have to be taken into account. One of the main challenges is the accurate modeling of antenna correlation that is directly related to the amount of channel capacity or diversity gain which might be achieved in multi element antenna configurations. Therefore spherical wave theory in electromagnetics is a well known technique to express antenna far fields by means of a compact field expansion with a reduced number of unknowns that was recently applied to derive an analytical approach in the computation of antenna pattern correlation. In this paper we present a novel and efficient computational technique to determine antenna pattern correlation based on the evaluation of the surface current distribution by means of a spherical mode expansion.

  9. Lumbar Vertebral Endplate Defects on Magnetic Resonance Images: Classification, Distribution Patterns, and Associations with Modic Changes and Disc Degeneration.

    Science.gov (United States)

    Feng, Zhiyun; Liu, Yuanhao; Yang, Ge; Battié, Michele C; Wang, Yue

    2017-10-10

    A cross-sectional MR imaging study. To classify and characterize endplate defects using routine lumbar MR images, and to determine associations of endplate defects with Modic Changes (MCs) and disc degeneration. Previously, a cadaveric study revealed that endplate lesions were common and associated with back pain history. New in vivo approaches appropriate for clinical studies are needed to further this potentially important line of research on the clinical significance of endplate lesions, including their relation with MCs, disc degeneration and back pain. Using a MRI archive, 1564 endplates of 133 subjects (59 men and 74 women, mean age 58.9 ± 11.9 years) with the presence of MCs were retrospectively collected from April of 2014 to June of 2015. Based on morphological characteristics, a protocol was proposed to identify three distinct types of endplate defects, including focal, corner and erosive defects. The location, size and distribution patterns of various endplate lesions were characterized. MCs and disc degeneration were measured to examine their associations with endplate defects. Endplate defects were observed in 27.8% of endplates studied. Greater age was associated with the presence of endplate defects. Focal defects were the most common (13.5%), followed by erosive defects (11.1%) and corner defects (3.2%). Defect types also differed in size and distribution patterns. Endplate defects and MCs had similar distribution patterns in the lumbar spine. The presence and size of endplate defects were associated with the presence of MCs (OR = 4.29, P system may facilitate clinical studies on endplate defects. 4.

  10. Dietary Protein Intake and Distribution Patterns of Well-Trained Dutch Athletes.

    Science.gov (United States)

    Gillen, Jenna B; Trommelen, Jorn; Wardenaar, Floris C; Brinkmans, Naomi Y J; Versteegen, Joline J; Jonvik, Kristin L; Kapp, Christoph; de Vries, Jeanne; van den Borne, Joost J G C; Gibala, Martin J; van Loon, Luc J C

    2017-04-01

    Dietary protein intake should be optimized in all athletes to ensure proper recovery and enhance the skeletal muscle adaptive response to exercise training. In addition to total protein intake, the use of specific proteincontaining food sources and the distribution of protein throughout the day are relevant for optimizing protein intake in athletes. In the present study, we examined the daily intake and distribution of various proteincontaining food sources in a large cohort of strength, endurance and team-sport athletes. Well-trained male (n=327) and female (n=226) athletes completed multiple web-based 24-hr dietary recalls over a 2-4 wk period. Total energy intake, the contribution of animal- and plant-based proteins to daily protein intake, and protein intake at six eating moments were determined. Daily protein intake averaged 108±33 and 90±24 g in men and women, respectively, which corresponded to relative intakes of 1.5±0.4 and 1.4±0.4 g/kg. Dietary protein intake was correlated with total energy intake in strength (r=0.71, p athletes. Animal and plant-based sources of protein intake was 57% and 43%, respectively. The distribution of protein intake was 19% (19±8 g) at breakfast, 24% (25±13 g) at lunch and 38% (38±15 g) at dinner. Protein intake was below the recommended 20 g for 58% of athletes at breakfast, 36% at lunch and 8% at dinner. In summary, this survey of athletes revealed they habitually consume > 1.2 g protein/kg/d, but the distribution throughout the day may be suboptimal to maximize the skeletal muscle adaptive response to training.

  11. Density and spatial distribution of Parkia biglobosa pattern in Benin under climate change

    Directory of Open Access Journals (Sweden)

    Fafunkè Titilayo Dotchamou

    2016-06-01

    Full Text Available Parkia biglobosa is an indigenous species which, traditionally contributes to the resilience of the agricultural production system in terms of food security, source of income, poverty reduction and ecosystem stability. Therefore, it is important to improve knowledge on its density, current and future spatial distribution. The main objective of this study is to evaluate the tree density, the climate change effects on the spatial distribution of the species in the future for better conservation. The modeling of the current and future geographical distribution of the species is based on the principle of Maximum Entropy (MaxEnt on a total of 286 occurrence points from field work and Global Biodiversity Information Facility GBIF-Data Portal-(www.gbif.org. Two climatic models (HadGEM2_ES and Csiro_mk3_6_0 have been used under two scenarios RCP 2.6 and RCP 8.5 for the projection of the species distribution at the horizon 2050. The correlation analyses and Jackknife test have helped to identify seven variables which are less correlated (r < 0.80 with highest modeling participation. The soil, annual precipitation (BIO12 and temperature (diurnal average Deviation are the variables which have mostly contributed to performance of the models. Currently, 53% of national territory, spread from north to south is very suitable to the cultivation of P. biglobosa. The scenarios have predicted at the horizon 2050, a loss of the habitats which are currently very suitable for the cultivation and conservation of P. biglobosa, to the benefit of moderate and weak habitats. 51% and 57% are the highest proportion of this lost which will be registered with HadGEM2_ES model under two scenarios. These results revealed that the suitable habitat of the species is threatened by climate change in Benin. In order to limit damage such as decreased productivity, extinction of species, some appropriate solutions must be found.

  12. Alien animals in South Africa – composition, introduction history, origins and distribution patterns

    OpenAIRE

    Mike D. Picker; Griffiths, Charles L.

    2017-01-01

    Background: There is no comprehensive inventory and analysis of the composition, distribution, origin and rate of introduction of the alien fauna of South Africa. Objectives: To provide such an analysis to facilitate effective ecological management, and compile a comprehensive inventory of introduced animal species across major habitats. Methods: All available databases and references were used to compile the inventory, forming the basis of subsequent analyses. A graduated map was produced to...

  13. Distribution Patterns and Phylogeny of Marine Stramenopiles in the North Pacific Ocean

    OpenAIRE

    Lin, Yun-Chi; Campbell, Tracy; Chung, Chih-Ching; Gong, Gwo-Ching; Chiang, Kuo-Ping; Worden, Alexandra Z.

    2012-01-01

    Marine stramenopiles (MASTs) are a diverse suite of eukaryotic microbes found in marine environments. Several MAST lineages are thought to contain heterotrophic nanoflagellates. However, MASTs remain uncultured and data on distributions and trophic modes are limited. We investigated MASTs in provinces on the west and east sides of the North Pacific Subtropical Gyre, specifically the East China Sea (ECS) and the California Current system (CALC). For each province, DNA was sampled from three zo...

  14. The pattern of distribution of laminin in neurogenic tumors, granular cell tumors, and nevi of the oral mucosa

    DEFF Research Database (Denmark)

    Reibel, J; Wewer, U; Albrechtsen, R

    1985-01-01

    Oral tumors of presumably neuroectodermal origin were stained with anti-laminin antibody by a double layered immunofluorescence technique. A marked positive staining for laminin was found in neurofibromas and neurilemmomas although the pattern of laminin distribution was slightly different...... in nests whole groups of cells were encircled by laminin as seen in the GCM. Ordinary oral fibromas included as controls were negative except for the expected positive staining of basement membranes normally occurring in the tissues. Immunohistochemical demonstration of laminin seems to be a valuable aid...... in differential diagnosis of soft tissue tumors and may provide useful information about the pathogenesis of various lesions....

  15. Stress distribution of GaN layer grown on micro-pillar patterned GaN templates

    OpenAIRE

    Nagarajan, S; Svensk, O.; Ali, M.; G. Naresh-Kumar; Trager-Cowan, C.; Suihkonen, S.; Sopanen, Markku; Lipsanen, Harri

    2013-01-01

    High-resolution Raman mapping of the stress distribution in an etched GaN micro-pillar template and a 5 μm thick GaN layer grown on a micro-pillar patterned GaN template is investigated. Raman mapping of the E2 (high) phonon shows differences in stress between the coalescing boundary, the top surface of the pillar region and around the GaN micro-pillar. Increased compressive stress is observed at the coalescing boundary of two adjacent GaN micro-pillars, when compared to the laterally grown G...

  16. Estudio Experimental de Patrones de Flujo Bifásico Aire-Agua en Tuberías Horizontales y Ligeramente Inclinadas Experimental Study of Air-Water Two-Phase Flow Patterns in Horizontal and Slightly Inclined Pipelines

    OpenAIRE

    Francisco García; Mahmoud Haoulo

    2009-01-01

    Se realizó un estudio experimental de patrones de flujo bifásico aire-agua en tuberías horizontales y ligeramente inclinadas. Se realizaron 493 experimentos de flujo bifásico aire-agua de los cuales 191 corresponden a tubería horizontal y 302 corresponden a flujo ascendente. Las distribuciones espaciales de los experimentos incluyen los patrones de flujo estratificado liso y ondulado, tapón, anular y burbuja dispersa. Se desarrollan mapas de patrones de flujo experimentales para cada ángulo d...

  17. [Predicting the impact of global warming on the geographical distribution pattern of Quercus variabilis in China].

    Science.gov (United States)

    Li, Yao; Zhang, Xing-wang; Fang, Yan-ming

    2014-12-01

    The geographical distribution of Quercus variabilis in China with its climate characteristics was analyzed based on DIVA-GIS which was also used to estimate the response of future potential distribution to global warming by Bioclim and Domain models. Analysis results showed the geographical distribution of Q. variabilis could be divided into 7 subregions: Henduan Mountains, Yunnan-Guizhou Plateau, North China, East China, Liaodong-Shandong Peninsula, Taiwan Island, and Qinling-Daba Mountains. These subregions are across 7 temperature zones, 2 moisture regions and 17 climatic subregions, including 8 climate types. The modern abundance center of Q. variabilis is Qinling, Daba and Funiu mountains. The condition of mean annual temperature 7.5-19.8 degrees C annual precipitation 471-1511 mm, is suitable for Q. variabilis. Areas under the receiver operating characteristic curve (AUC values), of Domain and Boiclim models were 0.910, 0.779; the former predicted that the potential regions of high suitability for Q. variabilis are Qinling, Daba, Funiu, Tongbai, and Dabie mountains, eastern and western Yunnan-Guizhou Plateau, hills of southern Jiangsu and Anhui, part of the mountains in North China. Global warming might lead to the shrinking in suitable region and retreating from the south for Q. variabilis.

  18. Patterns of distribution, abundance, and change over time in a subarctic marine bird community

    Science.gov (United States)

    Cushing, Daniel; Roby, Daniel D.; Irons, David B.

    2017-01-01

    Over recent decades, marine ecosystems of Prince William Sound (PWS), Alaska, have experienced concurrent effects of natural and anthropogenic perturbations, including variability in the climate system of the northeastern Pacific Ocean. We documented spatial and temporal patterns of variability in the summer marine bird community in relation to habitat and climate variability using boat-based surveys of marine birds conducted during the period 1989–2012. We hypothesized that a major factor structuring marine bird communities in PWS would be proximity to the shoreline, which is theorized to relate to aspects of food web structure. We also hypothesized that shifts in physical ecosystem drivers differentially affected nearshore-benthic and pelagic components of PWS food webs. We evaluated support for our hypotheses using an approach centered on community-level patterns of spatial and temporal variability. We found that an environmental gradient related to water depth and distance from shore was the dominant factor spatially structuring the marine bird community. Responses of marine birds to this onshore-offshore environmental gradient were related to dietary specialization, and separated marine bird taxa by prey type. The primary form of temporal variability over the study period was monotonic increases or decreases in abundance for 11 of 18 evaluated genera of marine birds; 8 genera had declined, whereas 3 had increased. The greatest declines occurred in genera associated with habitats that were deeper and farther from shore. Furthermore, most of the genera that declined primarily fed on pelagic prey resources, such as forage fish and mesozooplankton, and few were directly affected by the 1989 Exxon Valdez oil spill. Our observations of synchronous declines are indicative of a shift in pelagic components of PWS food webs. This pattern was correlated with climate variability at time-scales of several years to a decade.

  19. Climate and landscape explain richness patterns depending on the type of species' distribution data

    Science.gov (United States)

    Tsianou, Mariana A.; Koutsias, Nikolaos; Mazaris, Antonios D.; Kallimanis, Athanasios S.

    2016-07-01

    Understanding the patterns of species richness and their environmental drivers, remains a central theme in ecological research and especially in the continental scales where many conservation decisions are made. Here, we analyzed the patterns of species richness from amphibians, reptiles and mammals at the EU level. We used two different data sources for each taxon: expert-drawn species range maps, and presence/absence atlases. As environmental drivers, we considered climate and land cover. Land cover is increasingly the focus of research, but there still is no consensus on how to classify land cover to distinct habitat classes, so we analyzed the CORINE land cover data with three different levels of thematic resolution (resolution of classification scheme ˗ less to more detailed). We found that the two types of species richness data explored in this study yielded different richness maps. Although, we expected expert-drawn range based estimates of species richness to exceed those from atlas data (due to the assumption that species are present in all locations throughout their region), we found that in many cases the opposite is true (the extreme case is the reptiles where more than half of the atlas based estimates were greater than the expert-drawn range based estimates). Also, we detected contrasting information on the richness drivers of biodiversity patterns depending on the dataset used. For atlas based richness estimates, landscape attributes played more important role than climate while for expert-drawn range based richness estimates climatic variables were more important (for the ectothermic amphibians and reptiles). Finally we found that the thematic resolution of the land cover classification scheme, also played a role in quantifying the effect of land cover diversity, with more detailed thematic resolution increasing the relative contribution of landscape attributes in predicting species richness.

  20. Effect of feed flow pattern on the distribution of permeate fluxes in desalination by direct contact membrane distillation

    KAUST Repository

    Soukane, Sofiane

    2017-05-31

    The current study aims to highlight the effect of flow pattern on the variations of permeate fluxes over the membrane surface during desalination in a direct contact membrane distillation (DCMD) flat module. To do so, a three dimensional (3D) Computational Fluid Dynamics (CFD) model with embedded pore scale calculations is implemented to predict flow, heat and mass transfer in the DCMD module. Model validation is carried out in terms of average permeate fluxes with experimental data of seawater desalination using two commercially available PTFE membranes. Average permeate fluxes agree within 6% and less with experimental values without fitting parameters. Simulation results show that the distribution of permeate fluxes and seawater salinity over the membrane surface are strongly dependent on momentum and heat transport and that temperature and concentration polarization follow closely the flow distribution. The analysis reveals a drastic effect of recirculation loops and dead zones on module performance and recommendations to improve MD flat module design are drawn consequently.

  1. Distribution pattern of anthropogenic marine debris along the gastrointestinal tract of green turtles (Chelonia mydas) as implications for rehabilitation.

    Science.gov (United States)

    Colferai, André S; Silva-Filho, Rodolfo Pinho; Martins, Aryse Moreira; Bugoni, Leandro

    2017-06-15

    Pollution from anthropogenic marine debris (AMD) is currently the most widely distributed and lasting anthropic impact in the marine environment, affecting hundreds of species, including all sea turtles. In this study, the patterns of AMD distribution along the gastrointestinal tract (GT) and their relationship with obstructions and faecalomas in 62 green turtles (Chelonia mydas) that died during rehabilitation in southern Brazil were determined. The GT was split in seven sections, corresponding to the natural organs and intestinal areas morphologically and physiologically distinct. Mean mass (4.24g) and area (146.74cm2) of AMD in the stomach were higher than in other sections. The anterior portion of the rectum had the highest number of obstructions, followed by the stomach. AMD was associated with the obstructions, with positive correlation between faecalomas and AMD masses. Organs and subdivisions showed marked differences in susceptibility to obstructions caused by AMD, which deserves attention in clinical interventions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Mercury concentrations in Atlantic bottlenose dolphins (Tursiops truncatus) inhabiting the Indian River Lagoon, Florida: Patterns of spatial and temporal distribution.

    Science.gov (United States)

    Schaefer, Adam M; Titcomb, Elizabeth Murdoch; Fair, Patricia A; Stavros, Hui-Chen W; Mazzoil, Marilyn; Bossart, Gregory D; Reif, John S

    2015-08-15

    Bottlenose dolphins (Tursiops truncatus) inhabiting the Indian River Lagoon, FL (IRL) have tissue mercury concentrations among the highest reported worldwide. Analysis of total mercury (THg) concentrations in blood collected between 2003 and 2012 showed a significant linear decrease over time (p=0.04). Significant differences in the spatial distribution of THg in resident IRL dolphins were also observed with a general gradient in concentration from north to south. Evaluation of local biogeochemistry and accumulation of mercury in prey species is needed to better understand factors influencing the distribution of Hg in the apex predator. Analyses of temporal and spatial patterns of exposure to THg in this sentinel species may have implications for both ecosystem and public health in the region. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Colocalization coefficients evaluating the distribution of molecular targets in microscopy methods based on pointed patterns

    Czech Academy of Sciences Publication Activity Database

    Pastorek, Lukáš; Sobol, Margaryta; Hozák, Pavel

    2016-01-01

    Roč. 146, č. 4 (2016), s. 391-406 ISSN 0948-6143 R&D Projects: GA TA ČR(CZ) TE01020118; GA ČR GA15-08738S; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk(CZ) LM2015062 Grant - others:Human Frontier Science Program(FR) RGP0017/2013 Institutional support: RVO:68378050 Keywords : Colocalization * Quantitative analysis * Pointed patterns * Transmission electron microscopy * Manders' coefficients * Immunohistochemistry Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.553, year: 2016

  4. Judicious distribution of laser emitters to shape the desired far-field patterns

    Science.gov (United States)

    Valagiannopoulos, Constantinos A.; Kovanis, Vassilios

    2017-06-01

    The far-field pattern of a simple one-dimensional laser array of emitters radiating into free space is considered. In the course of investigating the inverse problem for their near fields leading to a target beam form, surprisingly, we found that the result is successful when the matrix of the corresponding linear system is not well scaled. The essence of our numerical observations is captured by an elegant inequality defining the functional range of the optical distance between two neighboring emitters. Our finding can restrict substantially the parametric space of integrated photonic systems and simplify significantly the subsequent optimizations.

  5. A Unique Pattern of HCV Genotype Distribution on Hainan Island in China Revealed by Evolutionary Analysis.

    Science.gov (United States)

    Wu, Tao; Xiong, Lu; Wang, Fuli; Xu, Xiaozhen; Wang, Jiao; Lin, Feng; Li, Chunhua; Lu, Ling; Zhou, Yuanping

    2016-01-01

    Different genotypes of HCV may differ in both disease progression and response to antiviral therapies. Hainan Island has been inhabited by the "Li" aboriginal minority for centuries. We aimed to provide a better understanding of HCV infection on Hainan Island, so that the information would help improve strategies for HCV prevention and control on the island and in the wider country. Using RT-PCR and DNA sequencing, we determined HCV sequences from 100 patients living on Hainan Island. Phylogenetic analysis classified these sequences into six subtypes: 6a (n=35), 1b (n=31), 3b (n=16), 2a (n=8), 3a (n=6), and 1a (n=4). By including reference sequences reported from elsewhere in China, phylogeographic trees were reconstructed to indicate their migration patterns. While the predominant 6a isolates were estimated to have origins in Guangdong and Guangxi provinces, the increase in 3b strains must have resulted from IDU network transmission from the southwest. A Bayesian Skyline Plot for subtype 1a, which is rare in China, showed a rapid population growth since 1998. Although slowed in rate around 2005, this growth continued to the present. Not found for any other HCV lineage. Overall, a delayed growth pattern may indicate the unique history of 1a dissemination in China and its recently increasing prevalence, despite measures taken to improve HCV prevention. © 2016 The Author(s) Published by S. Karger AG, Basel.

  6. A Unique Pattern of HCV Genotype Distribution on Hainan Island in China Revealed by Evolutionary Analysis

    Directory of Open Access Journals (Sweden)

    Tao Wu

    2016-06-01

    Full Text Available Background/Aims: Different genotypes of HCV may differ in both disease progression and response to antiviral therapies. Hainan Island has been inhabited by the “Li” aboriginal minority for centuries. We aimed to provide a better understanding of HCV infection on Hainan Island, so that the information would help improve strategies for HCV prevention and control on the island and in the wider country. Methods: Using RT-PCR and DNA sequencing, we determined HCV sequences from 100 patients living on Hainan Island. Results: Phylogenetic analysis classified these sequences into six subtypes: 6a (n=35, 1b (n=31, 3b (n=16, 2a (n=8, 3a (n=6, and 1a (n=4. By including reference sequences reported from elsewhere in China, phylogeographic trees were reconstructed to indicate their migration patterns. While the predominant 6a isolates were estimated to have origins in Guangdong and Guangxi provinces, the increase in 3b strains must have resulted from IDU network transmission from the southwest. A Bayesian Skyline Plot for subtype 1a, which is rare in China, showed a rapid population growth since 1998. Although slowed in rate around 2005, this growth continued to the present. Not found for any other HCV lineage. Conclusions: Overall, a delayed growth pattern may indicate the unique history of 1a dissemination in China and its recently increasing prevalence, despite measures taken to improve HCV prevention.

  7. Mudflat nekton assemblages in the Tagus estuary (Portugal: distribution and feeding patterns

    Directory of Open Access Journals (Sweden)

    Susana França

    2008-09-01

    Full Text Available Mudflats are an important component of estuaries, where they may occupy large areas and provide feeding and nursery grounds for many fish and bird species, as in the Tagus estuary. However, knowledge on their role and functioning is still expanding. Spatial and temporal dynamics of nekton assemblages in a mudflat of the Tagus estuary were evaluated to determine their role in the estuarine functioning. Feeding activity and daily rations of the most important nekton species are also analyzed. Two intertidal mudflat areas (upper and lower were sampled, as well as the adjoining subtidal area. Sampling was conducted every two months, during a yearly cycle. A 24 h sampling cycle was conducted to investigate daily feeding patterns and determine daily rations. Crangon crangon, Carcinus maenas, Palaemon longirostris, Palaemon serratus and Pomatoschistus microps dominated the nekton community. A marked seasonal pattern was noticed with the highest densities recorded in spring and summer, corresponding to recruitment episodes of these species. Highest biomass values were recorded in the subtidal zone, while the highest densities were recorded in the intertidal zone. The mudflats seem to play an important role in the dynamics of the Tagus estuary, acting as a feeding and nursery areas for several nektonic species.

  8. 3-D analysis of semiconductor dopant distributions in a patterned structure using LEAP

    Energy Technology Data Exchange (ETDEWEB)

    Moore, J.S. [Department of Materials Science and Engineering, University of Florida, P.O. Box 116130, 525 Engineering Builing, Gainesville, FL 32611 (United States)], E-mail: jsm200@ufl.edu; Jones, K.S. [Department of Materials Science and Engineering, University of Florida, P.O. Box 116130, 525 Engineering Builing, Gainesville, FL 32611 (United States); Kennel, H.; Corcoran, S. [Intel Corporation, Hillsboro, OR (United States)

    2008-05-15

    This work presents the first 3-D analysis of lateral dopant diffusion in a patterned structure using a pulsed laser-assisted local electrode atom probe (LEAP). A structure similar to a device channel was created for this work by performing a 3 keV, 1x10{sup 15} cm{sup -2} As{sup +} implant on a poly-Si line patterned wafer with 70 nm line width and 200 nm line pitch. The wafer was subsequently annealed at 950 deg. C for 1 s. LEAP samples were made using a site-selective in-situ focused ion beam (FIB) process. The results from LEAP analysis were then compared with high-resolution transmission electron microscopy (HRTEM) and Florida object-oriented process simulator (FLOOPS) results. Good structural agreement was found between the LEAP and HRTEM results. Several 1-D As concentration profiles extracted from the LEAP data were also found to be in good agreement with FLOOPS process simulation results. These profiles also represent for the first time that results from a 3-D process simulator have been able to be confirmed experimentally using a single sample.

  9. Distribution patterns of invasive Monk parakeets (Myiopsitta monachus in an urban habitat

    Directory of Open Access Journals (Sweden)

    Rodríguez–Pastor, R.

    2012-01-01

    Full Text Available Several invasive species have been shown to have a marked preference for urban habitats. The study of the variables responsible for the distribution of these species within urban habitats should allow to predict which environmental variables are indicative of preferred habitat, and to design landscape characteristics that make these areas less conducive to these species. The Monk parakeet Myiopsitta monachus is an invasive species in many American and European countries, and cities are one of its most usual habitats in invaded areas. The aim of this paper was to identify the main factors that determine distribution of the Monk parakeet in Barcelona, one of the cities in the world with the highest parakeet density. We defined our model based on eight preselected variables using a generalized linear model (GLZ and evaluated the strength of support for each model using the AIC–based multi–model inference approach. We used parakeet density as a dependent variable, and an analysis restricted to occupied neighbourhoods provided a model with two key variables to explain the distribution of the species. Monk parakeets were more abundant in neighbourhoods with a high density of trees and a high percentage of people over 65 years. This is interpreted by the fact that parakeets use trees as food sources and support for the nests, and that older people often feed the species. Data support the ‘human–activity’ hypothesis to explain how invasive species can successfully establish in a non–native habitat, and stress how limiting food resources, especially food supplied by humans, may be the easiest way to exert some control on Monk parakeet populations.

  10. Determinants of distribution patterns and management needs in a Critically Endangered lion Panthera leo population

    Directory of Open Access Journals (Sweden)

    Philipp Henschel

    2016-09-01

    Full Text Available The lion Panthera leo is Critically Endangered in West Africa and is known to occupy only four protected areas within the region. The largest population persists in the trans-boundary W-Arly-Pendjari (WAP ecosystem, in the border region of Benin, Burkina Faso, and Niger. WAP harbors an estimated 350 individuals, or 90% of West Africa’s lions. We modeled lion occupancy across WAP using systematic, vehicle-based spoor counts to assess how landscape variables related to biotic factors, management and human impact influence lion distribution across WAP. We surveyed 1110 km of roads across WAP in 2012, obtaining 79 lion detections in 32 of our 167 15 x 15 km sampling units (naïve occupancy = 0.41. Overall occupancy (Ψ was 0.71 (95% SE = 0.56-0.83 when accounting for imperfect detection (p = 0.22, 95% SE = 0.18-0.27. The best predictors of lion occupancy were numbers of permanent protected area staff and mean monthly dry season precipitation. Model-averaged estimates suggest greatest lion occupancy in the Arly and Pendjari management blocks, with lowest occupancy in the tri-national W National Park. Our results suggest that lions in WAP are equally limited by management and biotic factors, and demonstrate how unevenly distributed protection effort limits the distribution of an apex predator across a protected landscape. We strongly recommend increased funding and better protection to increase lion occupancy in WAP, most urgently in the W National Park.

  11. Norwegian house mice (Mus musculus musculus/domesticus): distributions, routes of colonization and patterns of hybridization.

    Science.gov (United States)

    Jones, Eleanor P; Van Der Kooij, Jeroen; Solheim, Roar; Searle, Jeremy B

    2010-12-01

    We investigated the distributions and routes of colonization of two commensal subspecies of house mouse in Norway: Mus musculus domesticus and M. m. musculus. Five nuclear markers (Abpa, D11 cenB2, Btk, SMCY and Zfy2) and a morphological feature (tail length) were used to differentiate the two subspecies and assess their distributions, and mitochondrial (mt) D-loop sequences helped to elucidate their colonization history. M. m. domesticus is the more widespread of the two subspecies, occupying the western and southern coast of Norway, while M. m. musculus is found along Norway's southeastern coast and east from there to Sweden. Two sections of the hybrid zone between the two subspecies were localized in Norway. However, hybrid forms also occur well away from that hybrid zone, the most prevalent of which are mice with a M. m. musculus-type Y chromosome and an otherwise M. m. domesticus genome. MtDNA D-loop sequences of the mice revealed a complex phylogeography within M. m. domesticus, reflecting passive human transport to Norway, probably during the Viking period. M. m. musculus may have colonized earlier. If so, that leaves open the possibility that M. m. domesticus replaced M. m. musculus from much of Norway, with the widely distributed hybrids a relict of this process. Overall, the effects of hybridization are evident in house mice throughout Norway. © 2010 Blackwell Publishing Ltd.

  12. Spatial distribution pattern and sequential sampling plans for Bactrocera oleae (Gmelin (Dip: Tephritidae in olive orchards

    Directory of Open Access Journals (Sweden)

    A. Arbab

    2016-04-01

    Full Text Available The distribution of adult and larvae Bactrocera oleae (Diptera: Tephritidae, a key pest of olive, was studied in olive orchards. The first objective was to analyze the dispersion of this insect on olive and the second was to develop sampling plans based on fixed levels of precision for estimating B. oleae populations. The Taylor’s power law and Iwao’s patchiness regression models were used to analyze the data. Our results document that Iwao’s patchiness provided a better description between variance and mean density. Taylor’s b and Iwao’s β were both significantly more than 1, indicating that adults and larvae had aggregated spatial distribution. This result was further supported by the calculated common k of 2.17 and 4.76 for adult and larvae, respectively. Iwao’s a for larvae was significantly less than 0, indicating that the basic distribution component of B. oleae is the individual insect. Optimal sample sizes for fixed precision levels of 0.10 and 0.25 were estimated with Iwao’s patchiness coefficients. The optimum sample size for adult and larvae fluctuated throughout the seasons and depended upon the fly density and desired level of precision. For adult, this generally ranged from 2 to 11 and 7 to 15 traps to achieve precision levels of 0.25 and 0.10, respectively. With respect to optimum sample size, the developed fixed-precision sequential sampling plans was suitable for estimating flies density at a precision level of D=0.25. Sampling plans, presented here, should be a tool for research on pest management decisions of B. oleae.

  13. Temperature drives global patterns in forest biomass distribution in leaves, stems, and roots

    Science.gov (United States)

    Reich, Peter B.; Lou, Yunjian; Bradford, John B.; Poorter, Hendrik; Perry, Charles H.; Oleksyn, Jacek

    2014-01-01

    Whether the fraction of total forest biomass distributed in roots, stems, or leaves varies systematically across geographic gradients remains unknown despite its importance for understanding forest ecology and modeling global carbon cycles. It has been hypothesized that plants should maintain proportionally more biomass in the organ that acquires the most limiting resource. Accordingly, we hypothesize greater biomass distribution in roots and less in stems and foliage in increasingly arid climates and in colder environments at high latitudes. Such a strategy would increase uptake of soil water in dry conditions and of soil nutrients in cold soils, where they are at low supply and are less mobile. We use a large global biomass dataset (>6,200 forests from 61 countries, across a 40 °C gradient in mean annual temperature) to address these questions. Climate metrics involving temperature were better predictors of biomass partitioning than those involving moisture availability, because, surprisingly, fractional distribution of biomass to roots or foliage was unrelated to aridity. In contrast, in increasingly cold climates, the proportion of total forest biomass in roots was greater and in foliage was smaller for both angiosperm and gymnosperm forests. These findings support hypotheses about adaptive strategies of forest trees to temperature and provide biogeographically explicit relationships to improve ecosystem and earth system models. They also will allow, for the first time to our knowledge, representations of root carbon pools that consider biogeographic differences, which are useful for quantifying whole-ecosystem carbon stocks and cycles and for assessing the impact of climate change on forest carbon dynamics.

  14. Patterns of distribution of phosphomono-esterases on surfaces of demineralized bone

    DEFF Research Database (Denmark)

    Kirkeby, S; Vilmann, H

    1979-01-01

    Decalcification over short periods (5 days) with MnNa2 EDTA, MgNa2 EDTA and EGTA according to a method described in the present paper, creates sections of high quality with simultaneous good preservation of phosphomonoesterases on bone surfaces. In fact, the enzyme distribution seems...... to be comparable to that obtained by using undecalcified sections. Na2 EDTA creates, on the other hand, poor preservation of alkaline phosphatase probably due to the fact that this chelate contrary to the other chelates removes the essential metal from the protein, leaving an unstable enzyme molecule which...

  15. Horizontal and Vertical Line Designs.

    Science.gov (United States)

    Johns, Pat

    2003-01-01

    Presents an art lesson in which students learn about the artist Piet Mondrian and create their own abstract artworks. Focuses on geometric shapes using horizontal and vertical lines. Includes background information about the artist. (CMK)

  16. Notes on the horizontal cohomology

    OpenAIRE

    Verbovetsky, Alexander

    1998-01-01

    This paper is devoted to the horizontal (``characteristic'') cohomology of systems of differential equations. Recent results on computing the horizontal cohomology via the compatibility complex are generalized. New results on the Vinogradov C-spectral sequence and the Krasil'shchik C-cohomology are obtained. As an application of general theory, the examples of an evolution equation and a p-form gauge theory are explicitly worked out.

  17. Mechanisms of Horizontal Gene Transfer

    OpenAIRE

    Cafini Barrado, Fabio; Medrano Romero, Verónica; Morikawa, Kazuya

    2017-01-01

    Horizontal gene transfer plays important roles in the evolution of S. aureus, and indeed, a variety of virulence factors and antibiotic resistance genes are embedded in a series of mobile genetic elements. In this chapter, we review the mechanisms of horizontal gene transfer, including recent findings on the natural genetic competence. Then, we consider the transfer of two important antibiotic resistance genes: the methicillin resistance gene, mecA (in Staphylococcal Cassette Chromosome) and ...

  18. Analysis of the electrical disturbances in CERN power distribution network with pattern mining methods

    CERN Document Server

    Abramenko, Oleksii

    2017-01-01

    The current research focuses on the perturbations within the electrical network of the LHC and its subsystems by analyzing measurements collected from oscilloscopes installed across different CERN sites, and alarms by electrical equipments. We analyze amplitude and duration of the glitches and, together with other relevant variables, correlate them with beam stopping events. The work also tries to identify assets affected by such perturbations using data mining and, in particular, frequent pattern mining methods. On the practical side we summarize results of our work by putting forward a prototype of a software tool enabling online monitoring of the alarms coming from the electrical network and facilitating glitch detection and analysis by a technical operator.

  19. Pattern of division and distribution of the mesenteric arteries in nutria (Myocastor coypus – Rodentia: Mammalia

    Directory of Open Access Journals (Sweden)

    Adelvino Parizzi

    2006-03-01

    Full Text Available For the recognition of the anatomical pattern of the mesenteric arteries, ten adults nutria (Myocastor coypus, males and females, were dissected, and the following results were obtained: a The cranial mesenteric artery appears from the ventral face of the abdominal aorta, close to the celiac artery (70%, or as a common trunk with it (30%. b The direct branches of the cranial mesenteric artery are the caudal pancreaticoduodenal (100%, middle colic (100%, duodenojejunal (90%, pancreatic (10%, hepatic (10%, right colic (100%, jejunal (100%, ileocolic (100% and ileal (100% arteries. The caudal mesenteric artery appears from the ventral face of the abdominal aorta, immediately cranial to the emergence of the external iliac arteries, and it separates to form the cranial rectal and left colic arteries. This left colic artery can be anastomosed (30%, along the wall of the descending colon, with the descending branch of the middle colic artery.

  20. Lazarus ecology: Recovering the distribution and migratory patterns of the extinct Carolina parakeet.

    Science.gov (United States)

    Burgio, Kevin R; Carlson, Colin J; Tingley, Morgan W

    2017-07-01

    The study of the ecology and natural history of species has traditionally ceased when a species goes extinct, despite the benefit to current and future generations of potential findings. We used the extinct Carolina parakeet as a case study to develop a framework investigating the distributional limits, subspecific variation, and migratory habits of this species as a means to recover important information about recently extinct species. We united historical accounts with museum collections to develop an exhaustive, comprehensive database of every known occurrence of this once iconic species. With these data, we combined species distribution models and ordinal niche comparisons to confront multiple conjectured hypotheses about the parakeet's ecology with empirical data on where and when this species occurred. Our results demonstrate that the Carolina parakeet's range was likely much smaller than previously believed, that the eastern and western subspecies occupied different climatic niches with broad geographical separation, and that the western subspecies was likely a seasonal migrant while the eastern subspecies was not. This study highlights the novelty and importance of collecting occurrence data from published observations on extinct species, providing a starting point for future investigations of the factors that drove the Carolina parakeet to extinction. Moreover, the recovery of lost autecological knowledge could benefit the conservation of other parrot species currently in decline and would be crucial to the success of potential de-extinction efforts for the Carolina parakeet.

  1. Distribution patterns predict individual specialization in the diet of dolphin gulls.

    Science.gov (United States)

    Masello, Juan F; Wikelski, Martin; Voigt, Christian C; Quillfeldt, Petra

    2013-01-01

    Many animals show some degree of individual specialization in foraging strategies and diet. This has profound ecological and evolutionary implications. For example, populations containing diverse individual foraging strategies will respond in different ways to changes in the environment, thus affecting the capacity of the populations to adapt to environmental changes and to diversify. However, patterns of individual specialization have been examined in few species. Likewise it is usually unknown whether specialization is maintained over time, because examining the temporal scale at which specialization occurs can prove difficult in the field. In the present study, we analyzed individual specialization in foraging in Dolphin Gulls Leucophaeus scoresbii, a scavenger endemic to the southernmost coasts of South America. We used GPS position logging and stable isotope analyses (SIA) to investigate individual specialization in feeding strategies and their persistence over time. The analysis of GPS data indicated two major foraging strategies in Dolphin Gulls from New I. (Falkland Is./Islas Malvinas). Tagged individuals repeatedly attended either a site with mussel beds or seabird and seal colonies during 5 to 7 days of tracking. Females foraging at mussel beds were heavier than those foraging at seabird colonies. Nitrogen isotope ratios (δ(15)N) of Dolphin Gull blood cells clustered in two groups, showing that individuals were consistent in their preferred foraging strategies over a period of at least several weeks. The results of the SIA as well as the foraging patterns recorded revealed a high degree of specialization for particular feeding sites and diets by individual Dolphin Gulls. Individual differences in foraging behavior were not related to sex. Specialization in Dolphin Gulls may be favored by the advantages of learning and memorizing optimal feeding locations and behaviors. Specialized individuals may reduce search and handling time and thus, optimize their

  2. Distribution patterns predict individual specialization in the diet of dolphin gulls.

    Directory of Open Access Journals (Sweden)

    Juan F Masello

    Full Text Available Many animals show some degree of individual specialization in foraging strategies and diet. This has profound ecological and evolutionary implications. For example, populations containing diverse individual foraging strategies will respond in different ways to changes in the environment, thus affecting the capacity of the populations to adapt to environmental changes and to diversify. However, patterns of individual specialization have been examined in few species. Likewise it is usually unknown whether specialization is maintained over time, because examining the temporal scale at which specialization occurs can prove difficult in the field. In the present study, we analyzed individual specialization in foraging in Dolphin Gulls Leucophaeus scoresbii, a scavenger endemic to the southernmost coasts of South America. We used GPS position logging and stable isotope analyses (SIA to investigate individual specialization in feeding strategies and their persistence over time. The analysis of GPS data indicated two major foraging strategies in Dolphin Gulls from New I. (Falkland Is./Islas Malvinas. Tagged individuals repeatedly attended either a site with mussel beds or seabird and seal colonies during 5 to 7 days of tracking. Females foraging at mussel beds were heavier than those foraging at seabird colonies. Nitrogen isotope ratios (δ(15N of Dolphin Gull blood cells clustered in two groups, showing that individuals were consistent in their preferred foraging strategies over a period of at least several weeks. The results of the SIA as well as the foraging patterns recorded revealed a high degree of specialization for particular feeding sites and diets by individual Dolphin Gulls. Individual differences in foraging behavior were not related to sex. Specialization in Dolphin Gulls may be favored by the advantages of learning and memorizing optimal feeding locations and behaviors. Specialized individuals may reduce search and handling time and thus

  3. Mars Global Digital Dune Database (MGD3): Global dune distribution and wind pattern observations

    Science.gov (United States)

    Hayward, Rosalyn K.; Fenton, Lori; Titus, Timothy N.

    2014-01-01

    The Mars Global Digital Dune Database (MGD3) is complete and now extends from 90°N to 90°S latitude. The recently released south pole (SP) portion (MC-30) of MGD3 adds ∼60,000 km2 of medium to large-size dark dune fields and ∼15,000 km2 of sand deposits and smaller dune fields to the previously released equatorial (EQ, ∼70,000 km2), and north pole (NP, ∼845,000 km2) portions of the database, bringing the global total to ∼975,000 km2. Nearly all NP dunes are part of large sand seas, while the majority of EQ and SP dune fields are individual dune fields located in craters. Despite the differences between Mars and Earth, their dune and dune field morphologies are strikingly similar. Bullseye dune fields, named for their concentric ring pattern, are the exception, possibly owing their distinctive appearance to winds that are unique to the crater environment. Ground-based wind directions are derived from slipface (SF) orientation and dune centroid azimuth (DCA), a measure of the relative location of a dune field inside a crater. SF and DCA often preserve evidence of different wind directions, suggesting the importance of local, topographically influenced winds. In general however, ground-based wind directions are broadly consistent with expected global patterns, such as polar easterlies. Intriguingly, between 40°S and 80°S latitude both SF and DCA preserve their strongest, though different, dominant wind direction, with transport toward the west and east for SF-derived winds and toward the north and west for DCA-derived winds.

  4. Spatial EMG potential distribution pattern of vastus lateralis muscle during isometric knee extension in young and elderly men.

    Science.gov (United States)

    Watanabe, Kohei; Kouzaki, Motoki; Merletti, Roberto; Fujibayashi, Mami; Moritani, Toshio

    2012-02-01

    The aim of the present study was to compare spatial electromyographic (EMG) potential distribution during force production between elderly and young individuals using multi-channel surface EMG (SEMG). Thirteen elderly (72-79years) and 13 young (21-27years) healthy male volunteers performed ramp submaximal contraction during isometric knee extension from 0% to 65% of maximal voluntary contraction. During contraction, multi-channel EMG was recorded from the vastus lateralis muscle. To evaluate alteration in heterogeneity and pattern in spatial EMG potential distribution, coefficient of variation (CoV), modified entropy and correlation coefficients with initial torque level were calculated from multi-channel SEMG at 5% force increment. Increase in CoV and decrease in modified entropy of RMS with increase of exerted torque were significantly smaller in elderly group (pchannel SEMG pattern in elderly individual reflects neuromuscular activation strategy regulated predominantly by clustering of similar type of muscle fibers in aged muscle. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Distribution pattern of psoriasis, anxiety and depression as possible causes of sexual dysfunction in patients with moderate to severe psoriasis.

    Science.gov (United States)

    Molina-Leyva, Alejandro; Almodovar-Real, Ana; Carrascosa, Jose Carlos-Ruiz; Molina-Leyva, Ignacio; Naranjo-Sintes, Ramon; Jimenez-Moleon, Jose Juan

    2015-01-01

    Psoriasis may significantly impair sexual function. Depression and organic factors appear to play a key role in this relation. However, beyond genital psoriasis, the importance of the disease's distribution patterns has not been considered. To research sexual function in psoriasis patients and investigate the roles of anxiety, depression and psoriasis' distribution patterns in sexual dysfunction. A comparative study matched for sex and age was performed. Eighty patients with moderate to severe psoriasis and 80 healthy controls were included. The participants completed the Massachusetts General Hospital-Sexual Functioning Questionnaire, the Hospital Anxiety and Depression Scale, and the Self-Administered Psoriasis Area and Severity Index. Psoriasis was associated with sexual dysfunction, odds ratio=5.5 (CI 95% 2.6-11.3; panxiety and depression, and the involvement of these specific areas, as possible independent risk factors for sexual dysfunction in patients with moderate to severe psoriasis. This study identifies body areas potentially related to sexual dysfunction, independently of anxiety and depression, in psoriasis patients. The results suggest that the assessment of sexual dysfunction and the involvement of these body areas should be considered as disease severity criteria when choosing the treatment for psoriasis patients.

  6. A new species of Austrolebias Costa (Cyprinodontiformes: Rivulidae from northeastern Uruguay, with comments on distribution patterns

    Directory of Open Access Journals (Sweden)

    Marcelo Loureiro

    Full Text Available A new species of Austrolebias is described based on individuals from the middle and upper río Negro (río Uruguay basin and río Yaguarón (Patos-Merín system. The new species can be differentiated from all other species of the genus by the unique presence in males of uniform bluish gray pigmentation on flanks (without vertical bands and unpaired fins. The new species is also distinguished by the combination of characters associated with a reduction of the squamation of the abdominal, preopercular, and opercular regions. The new species presents some morphological characteristics similar to A. gymnoventris and A. luteoflammulatus. The distribution of the new species is concordant with three other species of Austrolebias and may represent a case of drainage rearrangement of the río Negro upstream tributaries (río Uruguay basin and tributaries of laguna Merín system.

  7. Pattern of distribution of blood group antigens on human epidermal cells during maturation

    DEFF Research Database (Denmark)

    Dabelsteen, Erik; Buschard, Karsten; Hakomori, Sen-Itiroh

    1984-01-01

    monoclonal antibodies were used to identify H antigen (type 2 chain) and N-acetyl-lactosamine. Human antisera were used to identify A and B antigens. In all groups N-acetyl-lactosamine and H antigen were found on the cell membranes of the spinous cell layer. N-acetyl-lactosamine was present mainly...... on the lower spinous cells whereas H antigen was seen predominantly on upper spinous cells or on the granular cells. Epithelia from blood group A or B persons demonstrated A or B antigens, respectively, but only if the tissue sections were trypsinized before staining. In such cases A or B antigens were found......The distribution in human epidermis of A, B, and H blood group antigens and of a precursor carbohydrate chain, N-acetyl-lactosamine, was examined using immunofluorescence staining techniques. The material included tissue from 10 blood group A, 4 blood group B, and 9 blood group O persons. Murine...

  8. Distribution patterns of infection with multiple types of human papillomaviruses and their association with risk factors.

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    Sara Soto-De Leon

    Full Text Available BACKGROUND: Infection with multiple types of human papillomavirus (HPV is one of the main risk factors associated with the development of cervical lesions. In this study, cervical samples collected from 1,810 women with diverse sociocultural backgrounds, who attended to their cervical screening program in different geographical regions of Colombia, were examined for the presence of cervical lesions and HPV by Papanicolau testing and DNA PCR detection, respectively. PRINCIPAL FINDINGS: The negative binomial distribution model used in this study showed differences between the observed and expected values within some risk factor categories analyzed. Particularly in the case of single infection and coinfection with more than 4 HPV types, observed frequencies were smaller than expected, while the number of women infected with 2 to 4 viral types were higher than expected. Data analysis according to a negative binomial regression showed an increase in the risk of acquiring more HPV types in women who were of indigenous ethnicity (+37.8%, while this risk decreased in women who had given birth more than 4 times (-31.1%, or were of mestizo (-24.6% or black (-40.9% ethnicity. CONCLUSIONS: According to a theoretical probability distribution, the observed number of women having either a single infection or more than 4 viral types was smaller than expected, while for those infected with 2-4 HPV types it was larger than expected. Taking into account that this study showed a higher HPV coinfection rate in the indigenous ethnicity, the role of underlying factors should be assessed in detail in future studies.

  9. Different composition and distribution patterns of mineral-protected versus hydrolyzable lipids in shrubland soils

    Science.gov (United States)

    Cai, Yue; Tang, Zhiyao; Xiong, Gaoming; Xie, Zongqiang; Liu, Zongguang; Feng, Xiaojuan

    2017-09-01

    Mineral protection is known as an important mechanism stabilizing soil organic carbon (SOC). However, the composition, sources, and variations of mineral-protected SOC remain poorly constrained. To fill this knowledge gap, we used hydrofluoric acid to demineralize soil matrix and compared the sources and distribution of mineral-protected lipids (ML) versus hydrolyzable lipids (HL) of four typical Chinese shrubland soils. ML was found to represent a sizable fraction (9-32%) of total aliphatic lipids (including n-alkanols; n-alkanoic acids; α,ω-alkanedioic acids; hydroxyalkanoic acids; and midchain-substituted acids) in all soils. Based on carbon chain length and branch positions, microbe- and plant-derived lipids were distinguished. No significant difference was found in the ratio of microbe- to plant-derived lipids in ML versus HL, implying that plant and microbial inputs are equally important for the mineral-associated soil lipids. However, ML contained a higher proportion of nonspecific lipids, especially at depths. Furthermore, to evaluate key environmental variable(s) controlling the distribution of different lipid components, a multiple stepwise regression analysis was conducted. Notably, ML was mainly affected by SOC-to-nitrogen ratio instead of mineralogical properties, implying that the accrual of mineral-associated soil lipids relies strongly on organic matter properties. Collectively, our findings provide novel insights on sources and accumulation mechanisms of mineral-protected soil lipids. SOC decomposition and subsequent accretion of degradation products appear to be vital for the sequestration of mineral-associated soil lipids and warrant better recognition in the investigations of stable soil carbon accumulation mechanisms.

  10. Distribution patterns and environmental correlates of water mites (Hydrachnidia, Acari) in peatland microhabitats.

    Science.gov (United States)

    Więcek, Mariusz; Martin, Peter; Gąbka, Maciej

    2013-10-01

    In Europe peatlands are wetlands of postglacial origin. Because of climatic changes and agricultural activities (i.e. drainage and peat extraction), they are one of the most endangered ecosystems worldwide. Water mites are well known as indicators of changing environments in other ecosystems such as springs and lakes. For our study we selected seven peatlands located in North-Western Poland and focused on water mite distribution and associated habitat and water quality variables. We described water mite fauna in various microhabitats (aquatic and semiaquatic) along the mineral-richness gradient to test whether this gradient is reflected in the composition of water mite assemblages. We selected conductivity, pH and vegetation as variables reflecting the poor-rich gradient. Additionally, we measured water depth, temperature and dissolved oxygen, which are often important parameters for water mites. We also noted presence of prey and host taxa of particular water mite species. Based on physicochemical parameters we identified three types of habitats harbouring three distinctive species groups of water mites. We were able to distinguish species that appear to be typical of spring fens (e.g. Hygrobates norvegicus, Lebertia separata), connected with acidic, nutrient poor pools (e.g. Arrenurus neumani, A. pustulator) and species seemingly typical of temporary habitats dominated by Sphagnum mosses (e.g. Piersigia intermedia, Zschokkea oblonga, A. stecki). The poor-rich gradient is strongly reflected in the composition of water mite assemblages. We also found strong correlations between the water mite fauna and both conductivity and pH gradient. Our results show that water conductivity is the most important of the examined factors, driving mite-species distribution in