Science.gov

Sample records for cross regional cluster

  1. An Empirical Approach to Logical Clustering of Software Failure Regions

    DTIC Science & Technology

    1994-03-01

    that study was quite preliminary and local in its investigation. This thesis examines clustering from two other perspectives, taxonomical (type of...clustering was cross-examined across the perspectives. The results show that the studied failure regions have a strong tendency to form taxonornical...propagation of the fault (structural clustering). However, that study was quite preliminary and local in its investigation. This thesis examines clustering

  2. Cross-Clustering: A Partial Clustering Algorithm with Automatic Estimation of the Number of Clusters

    PubMed Central

    Tellaroli, Paola; Bazzi, Marco; Donato, Michele; Brazzale, Alessandra R.; Drăghici, Sorin

    2016-01-01

    Four of the most common limitations of the many available clustering methods are: i) the lack of a proper strategy to deal with outliers; ii) the need for a good a priori estimate of the number of clusters to obtain reasonable results; iii) the lack of a method able to detect when partitioning of a specific data set is not appropriate; and iv) the dependence of the result on the initialization. Here we propose Cross-clustering (CC), a partial clustering algorithm that overcomes these four limitations by combining the principles of two well established hierarchical clustering algorithms: Ward’s minimum variance and Complete-linkage. We validated CC by comparing it with a number of existing clustering methods, including Ward’s and Complete-linkage. We show on both simulated and real datasets, that CC performs better than the other methods in terms of: the identification of the correct number of clusters, the identification of outliers, and the determination of real cluster memberships. We used CC to cluster samples in order to identify disease subtypes, and on gene profiles, in order to determine groups of genes with the same behavior. Results obtained on a non-biological dataset show that the method is general enough to be successfully used in such diverse applications. The algorithm has been implemented in the statistical language R and is freely available from the CRAN contributed packages repository. PMID:27015427

  3. REGION OF GLOBULAR CLUSTER NGC 6397

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Right A NASA Hubble Space Telescope image of a small region (1.4 light-years across) in the globular star cluster NGC 6397 shows far fewer stars than would be expected in faint red dwarf stars were abundant. HST resolves about 200 stars. The stellar density is so low that HST can literally see right through the cluster and resolve far more distant background galaxies. This observation shows the surprising cutoff point below which nature apparently doesn't make many stars smaller that 1/5 the mass of our Sun. If there were lower mass stars in the cluster, then the image would contain an estimated 500 stars. This observation provides new insights into star formation in our Galaxy. Left A ground-based sky survey photograph of the globular cluster NGC 6397, one of the nearest and densest agglomerations of stars to Earth. The cluster is located 7,200 light-years away in the southern constellation Ara, and is one of 150 such objects which orbit our Milky Way Galaxy. Globular clusters are ideal laboratories for studying the formation and evolution of stars. This visible light picture was taken on March 3, 1994 with the Wide Field Planetary Camera 2, as part of the HST parallel observing program. Credit: F. Paresce, ST ScI and ESA and NASA

  4. Cluster in the Auroral Acceleration Region

    NASA Technical Reports Server (NTRS)

    Pickett, Jolene S.; Fazakerley, Andrew N.; Marklund, Gorun; Dandouras, Iannis; Christopher, Ivar W.; Kistler, Lynn; Lucek, Elizabeth; Masson, Arnaud; Taylor, Matthew G.; Mutel, Robert L.; Santolik, Ondrej; Bell, Timothy F.; Fung, Shing; Pottelette, Raymond; Hanasz, Jan; Schreiber, Roman; Hull, Arthur J.

    2010-01-01

    Due to a fortuitous evolution of the Cluster orbit, the Cluster spacecraft penetrated for the first time in its mission the heart of Earth's auroral acceleration region (AAR) in December 2009 and January 2010. During this time a special AAR campaign was carried out by the various Cluster instrument teams with special support from ESA and NASA facilities. We present some of the first multi-spacecraft observations of the waves, particles and fields made during that campaign. The Cluster spacecraft configuration during these AAR passages was such that it allowed us to explore the differences in the signatures of waves, particles, and fields on the various spacecraft in ways not possible with single spacecraft. For example, one spacecraft was more poleward than the other three (C2), one was at higher altitude (C1), and one of them (0) followed another (C4) through the AAR on approximately the same track but delayed by three minutes. Their separations were generally on the order of a few thousand km or less and occasionally two of them were lying along the same magnetic field line. We will show some of the first analyses of the data obtained during the AAR campaign, where upward and downward current regions, and the waves specifically associated with those regions, as well as the auroral cavities, were observed similarly and differently on the various spacecraft, helping us to explore the spatial, as well as the temporal, aspects of processes occurring in the AAR.

  5. Electron impact ionization cross sections of beryllium-tungsten clusters*

    NASA Astrophysics Data System (ADS)

    Sukuba, Ivan; Kaiser, Alexander; Huber, Stefan E.; Urban, Jan; Probst, Michael

    2016-01-01

    We report calculated electron impact ionization cross sections (EICSs) of beryllium-tungsten clusters, BenW with n = 1,...,12, from the ionization threshold to 10 keV using the Deutsch-Märk (DM) and the binary-encounter-Bethe (BEB) formalisms. The positions of the maxima of DM and BEB cross sections are mostly close to each other. The DM cross sections are more sensitive with respect to the cluster size. For the clusters smaller than Be4W they yield smaller cross sections than BEB and vice versa larger cross sections than BEB for clusters larger than Be6W. The maximum cross section values for the singlet-spin groundstate clusters range from 7.0 × 10-16 cm2 at 28 eV (BeW) to 54.2 × 10-16 cm2 at 43 eV (Be12W) for the DM cross sections and from 13.5 × 10-16 cm2 at 43 eV (BeW) to 38.9 × 10-16 cm2 at 43 eV (Be12W) for the BEB cross sections. Differences of the EICSs in different isomers and between singlet and triplet states are also explored. Both the DM and BEB cross sections could be fitted perfectly to a simple expression used in modeling and simulation codes in the framework of nuclear fusion research. Contribution to the Topical Issue "Atomic Cluster Collisions (7th International Symposium)", edited by Gerardo Delgado Barrio, Andrey Solov'Yov, Pablo Villarreal, Rita Prosmiti.Supplementary material in the form of one pdf file available from the Journal web page at http://dx.doi.org/10.1140/epjd/e2015-60583-7

  6. Membership determination of open cluster with parametric method: cross entropy

    NASA Astrophysics Data System (ADS)

    Khoirul Fitriana, Itsna; Ikbal Arifiyanto, M.

    2016-11-01

    Stellar open clusters are useful for studying the structure and evolution of Galaxy. Determination of the open cluster members can be viewed from their kinematics: proper motion and radial velocity. It is because the star cluster members will have a motion in the same direction, towards a convergent point. Parametric method with a double elliptic bivariate gaussian function which contains 11 parameters is used as a model of the proper motion distribution. The value of these parameters are determined numerically by cross entropy method. This method is a method of data fitting using the likelihood function whose value is maximized to get the proper parameters. This method solves the problem of determining the initial value that is often difficult to determine in other numerical methods. There are four open clusters which we have analysed: NGC 2244, ASCC 100, NGC 5168, and NGC 2169. The resulting of proper motion parameters of this method matches the parameters in the literature.

  7. Cluster Multi-Point Studies of the Auroral Acceleration Region

    NASA Astrophysics Data System (ADS)

    Marklund, G. T.

    2014-12-01

    Multi-point studies of the auroral acceleration region (AAR) by the Cluster spacecraft has enabled a number of open issues on the auroral acceleration to be addressed and revealed. Data from AAR crossings of Inverted-V aurora, by the C1 and C3 spacecraft at different altitudes, enabled a detailed reconstruction of the acceleration potential and a verification of its stability on a five min time scale. The relative role of quasi-static and Alfvénic acceleration behind aurora are addressed in two event studies. In one of these, the two processes are shown to operate jointly on the plasma population within the polar cap boundary. In the other, the electron energy flux producing multiple arcs within a surge is found to be generally dominated by the quasi-static contribution. Acceleration features and the FAC closure associated with surge-horn aurora crossed by the Cluster fleet were derived in another event study. A study of the density distribution within the auroral cavity, showed for all included events, exponential density decreases, relative to the ambient densities, from the mid to top of the AAR. In another study, cavities were found to extend well beyond the top of the AAR. Finally, statistical high-latitude electric field and plasma density distributions are presented based on 10 years of Cluster data collected between 2 and 4 RE altitudes. Intense electric fields appear in two altitude regimes on the nightside, separated by a gap at 2.8 RE. The upper altitude fields were interpreted to be Alfvénic and the lower altitude fields quasi-static, related to the AAR. The gap in the electric field intensity indicates a partial closure of the potentials in the lower region, with similarities to model results of reflected Alfvén waves and earlier reported observations

  8. Electron impact ionisation cross sections of iron hydrogen clusters

    NASA Astrophysics Data System (ADS)

    Huber, Stefan E.; Sukuba, Ivan; Urban, Jan; Limtrakul, Jumras; Probst, Michael

    2016-09-01

    We computed electron impact ionisation cross sections (EICSs) of iron hydrogen clusters, FeH n with n = 1,2, ...,10, from the ionisation threshold to 10 keV using the Deutsch-Märk (DM) and the binary-encounter-Bethe (BEB) formalisms. The maxima of the cross sections for the iron hydrogen clusters range from 6.13 × 10-16 cm2 at 60 eV to 8.76 × 10-16 cm2 at 76 eV for BEB-AE (BEB method based on quantum-chemical data from all-electron basis sets) calculations, from 4.15 × 10-16 cm2 at 77 eV to 7.61 × 10-16 cm2 at 80 eV for BEB-ECP (BEB method based on quantum-chemical data from effective-core potentials for inner-core electrons) calculations and from 2.49 × 10-16 cm2 at 43.5 eV to 7.04 × 10-16 cm2 at 51 eV for the DM method. Cross sections calculated via the BEB method are substantially higher than the ones obtained via the DM method, up to a factor of about two for FeH and FeH2. The formation of Fe-H bonds depopulates the iron 4 s orbital, causing significantly lower cross sections for the small iron hydrides compared to atomic iron. Both the DM and BEB cross sections can be fitted perfectly against a simple expression used in modelling and simulation codes in the framework of nuclear fusion research. The energetics of the iron hydrogen clusters change substantially when exact exchange is present in the density functional, while the cluster geometries do not depend on this choice.

  9. 75 FR 53667 - Space Coast Regional Innovation Cluster Competition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ....: 1008270400-0400-01] Space Coast Regional Innovation Cluster Competition AGENCY: Economic Development... announces the upcoming availability of funding for the Space Coast Regional Innovation Cluster (RIC... found at the Space Coast RIC Web site at http://www.eda.gov/SpaceCoastRIC . Applicants are advised...

  10. The Clusters - Collaborative Models of Sustainable Regional Development

    NASA Astrophysics Data System (ADS)

    Mănescu, Gabriel; Kifor, Claudiu

    2014-12-01

    The clusters are the subject of actions and of whole series of documents issued by national and international organizations, and, based on experience, many authorities promote the idea that because of the clusters, competitiveness increases, the workforce specializes, regional businesses and economies grow. The present paper is meant to be an insight into the initiatives of forming clusters in Romania. Starting from a comprehensive analysis of the development potential offered by each region of economic development, we present the main types of clusters grouped according to fields of activity and their overall objectives

  11. Clusters, deformation, and dilation: Diagnostics for material accumulation regions

    NASA Astrophysics Data System (ADS)

    Huntley, Helga S.; Lipphardt, B. L.; Jacobs, Gregg; Kirwan, A. D.

    2015-10-01

    Clusters of material at the ocean surface have been frequently observed. Such accumulations of material play an important role in a variety of applications, from biology to pollution mitigation. Identifying where clusters will form can aid in locating, for example, hotspots of biological activity or regions of high pollutant concentration. Here cluster strength is introduced as a new metric for defining clusters when all particle positions are known. To diagnose regions likely to contain clusters without the need to integrate millions of particle trajectories, we propose to use dilation, which quantifies area changes of Lagrangian patches. Material deformation is decomposed into dilation and area-preserving stretch processes to refine previous approaches based on finite-time Lyapunov exponents (FTLE) by splitting the FTLE into fundamental kinematic properties. The concepts are developed theoretically and illustrated in the context of a state-of-the-art data-assimilating predictive ocean model of the Gulf of Mexico. Regions of dilation less than one are shown to be much more likely (6 times more likely in the given example) to be visited by particles than those of dilation greater than one. While the relationship is nonlinear, dilation and cluster strength exhibit a fairly good correlation. In contrast, both stretch and Eulerian divergence are found to be uncorrelated with cluster strength. Thus, dilation maps can be used as guides for identifying cluster locations, while saving some of the computational cost of trajectory integrations.

  12. Using cluster analysis to organize and explore regional GPS velocities

    USGS Publications Warehouse

    Simpson, Robert W.; Thatcher, Wayne; Savage, James C.

    2012-01-01

    Cluster analysis offers a simple visual exploratory tool for the initial investigation of regional Global Positioning System (GPS) velocity observations, which are providing increasingly precise mappings of actively deforming continental lithosphere. The deformation fields from dense regional GPS networks can often be concisely described in terms of relatively coherent blocks bounded by active faults, although the choice of blocks, their number and size, can be subjective and is often guided by the distribution of known faults. To illustrate our method, we apply cluster analysis to GPS velocities from the San Francisco Bay Region, California, to search for spatially coherent patterns of deformation, including evidence of block-like behavior. The clustering process identifies four robust groupings of velocities that we identify with four crustal blocks. Although the analysis uses no prior geologic information other than the GPS velocities, the cluster/block boundaries track three major faults, both locked and creeping.

  13. Cluster Prototypes and Fuzzy Memberships Jointly Leveraged Cross-Domain Maximum Entropy Clustering

    PubMed Central

    Qian, Pengjiang; Jiang, Yizhang; Deng, Zhaohong; Hu, Lingzhi; Sun, Shouwei; Wang, Shitong; Muzic, Raymond F.

    2016-01-01

    The classical maximum entropy clustering (MEC) algorithm usually cannot achieve satisfactory results in the situations where the data is insufficient, incomplete, or distorted. To address this problem, inspired by transfer learning, the specific cluster prototypes and fuzzy memberships jointly leveraged (CPM-JL) framework for cross-domain MEC (CDMEC) is firstly devised in this paper, and then the corresponding algorithm referred to as CPM-JL-CDMEC and the dedicated validity index named fuzzy memberships-based cross-domain difference measurement (FM-CDDM) are concurrently proposed. In general, the contributions of this paper are fourfold: 1) benefiting from the delicate CPM-JL framework, CPM-JL-CDMEC features high-clustering effectiveness and robustness even in some complex data situations; 2) the reliability of FM-CDDM has been demonstrated to be close to well-established external criteria, e.g., normalized mutual information and rand index, and it does not require additional label information. Hence, using FM-CDDM as a dedicated validity index significantly enhances the applicability of CPM-JL-CDMEC under realistic scenarios; 3) the performance of CPM-JL-CDMEC is generally better than, at least equal to, that of MEC because CPM-JL-CDMEC can degenerate into the standard MEC algorithm after adopting the proper parameters, and which avoids the issue of negative transfer; and 4) in order to maximize privacy protection, CPM-JL-CDMEC employs the known cluster prototypes and their associated fuzzy memberships rather than the raw data in the source domain as prior knowledge. The experimental studies thoroughly evaluated and demonstrated these advantages on both synthetic and real-life transfer datasets. PMID:26684257

  14. The efficiency of star formation in clustered and distributed regions

    NASA Astrophysics Data System (ADS)

    Bonnell, Ian A.; Smith, Rowan J.; Clark, Paul C.; Bate, Matthew R.

    2011-02-01

    We investigate the formation of both clustered and distributed populations of young stars in a single molecular cloud. We present a numerical simulation of a 104 M⊙ elongated, turbulent, molecular cloud and the formation of over 2500 stars. The stars form both in stellar clusters and in a distributed mode, which is determined by the local gravitational binding of the cloud. A density gradient along the major axis of the cloud produces bound regions that form stellar clusters and unbound regions that form a more distributed population. The initial mass function (IMF) also depends on the local gravitational binding of the cloud with bound regions forming full IMFs whereas in the unbound, distributed regions the stellar masses cluster around the local Jeans mass and lack both the high-mass and the low-mass stars. The overall efficiency of star formation is ≈ 15 per cent in the cloud when the calculation is terminated, but varies from less than 1 per cent in the regions of distributed star formation to ≈ 40 per cent in regions containing large stellar clusters. Considering that large-scale surveys are likely to catch clouds at all evolutionary stages, estimates of the (time-averaged) star formation efficiency (SFE) for the giant molecular cloud reported here is only ≈ 4 per cent. This would lead to the erroneous conclusion of slow star formation when in fact it is occurring on a dynamical time-scale.

  15. Spatial connectivity of urban clusters and regional climate effects

    NASA Astrophysics Data System (ADS)

    Jia, G.; Hu, Y.; Xu, R.

    2015-12-01

    Rapid urbanization in East Asia in past three decades is considered as a remarkable process that featured with expansion of urban clusters and tightened linkages within and among clusters. Such process could lead to much larger scale climate effects, and could even contribute to sub-regional and regional climate change. In large area of urban clusters with significant expansion of built-up in relatively short period, local urban heat islands could contribute to sub-regional climate forcing. Here we use visible/near infrared and thermal infrared satellite data to estimate multiple scale structure of urban clusters, and to assess effects of urban heat islands at local and regional scales in East Asia. Our estimates of urban extent were greater than previously reported in most global datasets. Strong spatial connection and internal expansion were found in major urban clusters in past 30 years, and was accelerated in past 10 years. Many city clusters were merging into each other, with gradual blurring boundaries and disappearing of gaps among member cities. Cities and towns were more connected with roads and commercial corridors, while wildland and urban greens became more isolated as patches among built-up areas. We would argue that in many cases in this region, urban clusters are no longer "islands", they are now "seas" in term of climate related urban canopy. Urban greens such as parks and plantation were long recognized for their cooling effects that buffer the urban heat island effect, however, such cooling effects tend to be weakened as their patches became smaller and isolated, and over dominated by urban surfaces. There were significant positive relations between urban fraction and urban heat island effects as demonstrated by VNIR and TIR data from multiple satellites. Those new estimates are expected to effectively improve climate simulation for better understanding the impacts of inter-connected urban clusters on air temperature, precipitation, wind speed

  16. A statistical method (cross-validation) for bone loss region detection after spaceflight

    PubMed Central

    Zhao, Qian; Li, Wenjun; Li, Caixia; Chu, Philip W.; Kornak, John; Lang, Thomas F.

    2010-01-01

    Astronauts experience bone loss after the long spaceflight missions. Identifying specific regions that undergo the greatest losses (e.g. the proximal femur) could reveal information about the processes of bone loss in disuse and disease. Methods for detecting such regions, however, remains an open problem. This paper focuses on statistical methods to detect such regions. We perform statistical parametric mapping to get t-maps of changes in images, and propose a new cross-validation method to select an optimum suprathreshold for forming clusters of pixels. Once these candidate clusters are formed, we use permutation testing of longitudinal labels to derive significant changes. PMID:20632144

  17. HotRegion: a database of predicted hot spot clusters

    PubMed Central

    Cukuroglu, Engin; Keskin, Ozlem

    2012-01-01

    Hot spots are energetically important residues at protein interfaces and they are not randomly distributed across the interface but rather clustered. These clustered hot spots form hot regions. Hot regions are important for the stability of protein complexes, as well as providing specificity to binding sites. We propose a database called HotRegion, which provides the hot region information of the interfaces by using predicted hot spot residues, and structural properties of these interface residues such as pair potentials of interface residues, accessible surface area (ASA) and relative ASA values of interface residues of both monomer and complex forms of proteins. Also, the 3D visualization of the interface and interactions among hot spot residues are provided. HotRegion is accessible at http://prism.ccbb.ku.edu.tr/hotregion. PMID:22080558

  18. The smart cluster method - Adaptive earthquake cluster identification and analysis in strong seismic regions

    NASA Astrophysics Data System (ADS)

    Schaefer, Andreas M.; Daniell, James E.; Wenzel, Friedemann

    2017-03-01

    Earthquake clustering is an essential part of almost any statistical analysis of spatial and temporal properties of seismic activity. The nature of earthquake clusters and subsequent declustering of earthquake catalogues plays a crucial role in determining the magnitude-dependent earthquake return period and its respective spatial variation for probabilistic seismic hazard assessment. This study introduces the Smart Cluster Method (SCM), a new methodology to identify earthquake clusters, which uses an adaptive point process for spatio-temporal cluster identification. It utilises the magnitude-dependent spatio-temporal earthquake density to adjust the search properties, subsequently analyses the identified clusters to determine directional variation and adjusts its search space with respect to directional properties. In the case of rapid subsequent ruptures like the 1992 Landers sequence or the 2010-2011 Darfield-Christchurch sequence, a reclassification procedure is applied to disassemble subsequent ruptures using near-field searches, nearest neighbour classification and temporal splitting. The method is capable of identifying and classifying earthquake clusters in space and time. It has been tested and validated using earthquake data from California and New Zealand. A total of more than 1500 clusters have been found in both regions since 1980 with M m i n = 2.0. Utilising the knowledge of cluster classification, the method has been adjusted to provide an earthquake declustering algorithm, which has been compared to existing methods. Its performance is comparable to established methodologies. The analysis of earthquake clustering statistics lead to various new and updated correlation functions, e.g. for ratios between mainshock and strongest aftershock and general aftershock activity metrics.

  19. Cluster cross sections from pickup measurements: Are the established methods consistent?

    NASA Astrophysics Data System (ADS)

    Fedor, J.; Poterya, V.; Pysanenko, A.; Fárník, M.

    2011-09-01

    Pickup of several molecules, H2O, HBr, and CH3OH, and Ar atoms on free ArN clusters has been investigated in a molecular beam experiment. The pickup cross sections of the clusters with known mean sizes, bar{N}≈ 150 and 260 were measured by two independent methods: (i) the cluster beam velocity decrease due to the momentum transfer of the picked up molecules to the clusters, and (ii) Poisson distribution of a selected cluster fragment ion as a function of the pickup pressure. In addition, the pickup cross sections were calculated using molecular dynamics and Monte Carlo simulations. The simulations support the results of the velocity measurements. On the other hand, the Poisson distributions yield significantly smaller cross sections, inconsistent with the known ArN cluster sizes. These results are discussed in terms of: (i) an incomplete coagulation of guest molecules on the argon clusters when two or more molecules are picked up; and (ii) the fragmentation pattern of the embedded molecules and their clusters upon ionization on the Ar cluster. We conclude that the Poisson distribution method has to be cautiously examined, if conclusions should be drawn about the cluster cross section, or the mean cluster size bar{N}, and the number of picked up molecules.

  20. Galaxy Population in the Infall Regions of Intermediate Redshift Clusters

    NASA Astrophysics Data System (ADS)

    Verdugo, Miguel; Ziegler, Bodo L.

    2007-05-01

    We investigate 6 clusters of galaxies at intermediate redshift (0.18region is often called the infall region since here newly arriving galaxies from the surrounding field encounter the special environment of clusters for the first time. We selected 3 fields containing 2 clusters each from the X-ray Dark Cluster Survey (XDC, Gilbank et al. 2004 MNRAS, 348, 551G, G04). Each 40'x 40' field was observed with 7-8 slit-masks yielding 553 low-resolution galaxy spectra (R≈500). The results for the first field (R285) were already published by Gerken et al. (2004A&A, 421, 59G). We select [OII]λ3717 and Hα equivalent widths as indicators of star formation activity. In the analysis, we "averaged" 4 clusters: VMF73 (z=0.254) & VMF74 (z=0.18) in XDCS field R285 and VMF131 (z=0.295) & VMF132 (z=0.246) in field R265. We have found an increase of the star forming activity towards larger cluster-centric distances as well as towards shallower projected galaxy densities. Galaxies in the third field R220 exhibit a complex redshift structure which makes membership determination difficulty and were excluded of the overall analysis. However, we clearly identified the cluster VMF194 (z=0.211) and confirm another cluster at z=0.261 detected by G04. In addition, a group of galaxies with similar coordinates to VMF194 at z=0.243 is significant. We also detected a population of red star-forming galaxies, belonging to the red-sequence of the clusters and even redder. Those galaxies show a moderate star-forming activity and do not show any other spectral peculiarities. We do not detect any post-starburst galaxy nor AGN in our cluster sample.

  1. Observational and Numerical Diagnostics of Galaxy Cluster Outer Regions

    NASA Technical Reports Server (NTRS)

    Eckert, D.; Vazza, F.; Ettori, S.; Molendi, S.; Nagai, D.; Lau, E.; Roncarelli, M.; Rossetti, M.; Snowden, S. L.; Gastaldello, F.

    2011-01-01

    Aims. We present the analysis of a local (z = 0.04 - 0.2) sample of 31 galaxy clusters with the aim of measuring the density of the X-ray emitting gas in cluster outskirts. We compare our results with numerical simulations to set constraints on the azimuthal symmetry and gas clumping in the outer regions of galaxy clusters. Methods. We exploit the large field-of-view and low instrumental background of ROSAT/PSPC to trace the density of the intracluster gas out to the virial radius. We perform a stacking of the density profiles to detect a signal beyond r(sub 200) and measure the typical density and scatter in cluster outskirts. We also compute the azimuthal scatter of the profiles with respect to the mean value to look for deviations from spherical symmetry. Finally, we compare our average density and scatter profiles with the results of numerical simulations. Results. As opposed to several recent results, we observe a steepening of the density profiles beyond approximately 0.3r(sub 500). Comparing our density profiles with simulations, we find that non-radiative runs predict too steep density profiles, whereas runs including additional physics and/or gas clumping are in better agreement with the observed gas distribution. We note a systematic difference between cool-core and non-cool core clusters beyond approximately 0.3r(sub 200), which we explain by a different distribution of the gas in the two classes. Beyond approximately r(sub 500), galaxy clusters deviate significantly from spherical symmetry, with only little differences between relaxed and disturbed systems. We find good agreement between the observed and predicted scatter profiles, but only when the 1% densest clumps are filtered out in the simulations. Conclusions. The general trend of steepening density around the virial radius indicates that the shallow density profiles found in several recent works were probably obtained along particular directions (e.g., filaments) and are not representative of the

  2. The Gas Distribution in the Outer Regions of Galaxy Clusters

    NASA Technical Reports Server (NTRS)

    Eckert, D.; Vazza, F.; Ettori, S.; Molendi, S.; Nagai, D.; Lau, E. T.; Roncarelli, M.; Rossetti, M.; Snowden, L.; Gastaldello, F.

    2012-01-01

    Aims. We present our analysis of a local (z = 0.04 - 0.2) sample of 31 galaxy clusters with the aim of measuring the density of the X-ray emitting gas in cluster outskirts. We compare our results with numerical simulations to set constraints on the azimuthal symmetry and gas clumping in the outer regions of galaxy clusters. Methods. We have exploited the large field-of-view and low instrumental background of ROSAT/PSPC to trace the density of the intracluster gas out to the virial radius, We stacked the density profiles to detect a signal beyond T200 and measured the typical density and scatter in cluster outskirts. We also computed the azimuthal scatter of the profiles with respect to the mean value to look for deviations from spherical symmetry. Finally, we compared our average density and scatter profiles with the results of numerical simulations. Results. As opposed to some recent Suzaku results, and confirming previous evidence from ROSAT and Chandra, we observe a steepening of the density profiles beyond approximately r(sub 500). Comparing our density profiles with simulations, we find that non-radiative runs predict density profiles that are too steep, whereas runs including additional physics and/ or treating gas clumping agree better with the observed gas distribution. We report high-confidence detection of a systematic difference between cool-core and non cool-core clusters beyond approximately 0.3r(sub 200), which we explain by a different distribution of the gas in the two classes. Beyond approximately r(sub 500), galaxy clusters deviate significantly from spherical symmetry, with only small differences between relaxed and disturbed systems. We find good agreement between the observed and predicted scatter profiles, but only when the 1% densest clumps are filtered out in the ENZO simulations. Conclusions. Comparing our results with numerical simulations, we find that non-radiative simulations fail to reproduce the gas distribution, even well outside

  3. The Gas Distribution in Galaxy Cluster Outer Regions

    NASA Technical Reports Server (NTRS)

    Eckert, D.; Vazza, F.; Ettori, S.; Molendi, S.; Nagai, D.; Laue, E. T.; Roncarelli, M.; Rossetti, M.; Snowden, S. L.; Gastaldello, F.

    2012-01-01

    Aims. We present the analysis of a local (z = 0.04 - 0.2) sample of 31 galaxy clusters with the aim of measuring the density of the X-ray emitting gas in cluster outskirts. We compare our results with numerical simulations to set constraints on the azimuthal symmetry and gas clumping in the outer regions of galaxy clusters. Methods. We exploit the large field-of-view and low instrumental background of ROSAT/PSPC to trace the density of the intracluster gas out to the virial radius. We perform a stacking of the density profiles to detect a signal beyond r200 and measure the typical density and scatter in cluster outskirts. We also compute the azimuthal scatter of the profiles with respect to the mean value to look for deviations from spherical symmetry. Finally, we compare our average density and scatter profiles with the results of numerical simulations. Results. As opposed to some recent Suzaku results, and confirming previous evidence from ROSAT and Chandra, we observe a steepening of the density profiles beyond approximately r(sub 500). Comparing our density profiles with simulations, we find that non-radiative runs predict too steep density profiles, whereas runs including additional physics and/or treating gas clumping are in better agreement with the observed gas distribution. We report for the first time the high-confidence detection of a systematic difference between cool-core and non-cool core clusters beyond 0.3r(sub 200), which we explain by a different distribution of the gas in the two classes. Beyond r(sub 500), galaxy clusters deviate significantly from spherical symmetry, with only little differences between relaxed and disturbed systems. We find good agreement between the observed and predicted scatter profiles, but only when the 1% densest clumps are filtered out in the simulations. Conclusions. Comparing our results with numerical simulations, we find that non-radiative simulations fail to reproduce the gas distribution, even well outside cluster

  4. Angular cross-relations of Abell clusters in different distance classes

    NASA Technical Reports Server (NTRS)

    Szalay, A. S.; Hollosi, J.; Toth, G.

    1989-01-01

    The angular autocorrelation and cross-correlation functions of the D = 1 ... 4, D = 5, and D = 6 distance class Abell clusters are estimated. There is a strong anticorrelation between the most distant D = 6 and the closest D = 1 ... 4 subsamples. It is suggested that an artifact of the cluster identification process presumably due to the finite angular size of the cluster. This anticorrelation seems to contradict some recent estimations of projection contaminations in the Abell catalog. The angular proximity of a foreground cluster may have caused a background cluster not to be counted as it was thought to be a subcluster or it was erroneously assigned to a nearer distance class.

  5. A coupled-cluster study of photodetachment cross sections of closed-shell anions.

    PubMed

    Cukras, Janusz; Decleva, Piero; Coriani, Sonia

    2014-11-07

    We investigate the performance of Stieltjes Imaging applied to Lanczos pseudo-spectra generated at the coupled cluster singles and doubles, coupled cluster singles and approximate iterative doubles and coupled cluster singles levels of theory in modeling the photodetachment cross sections of the closed shell anions H(-), Li(-), Na(-), F(-), Cl(-), and OH(-). The accurate description of double excitations is found to play a much more important role than in the case of photoionization of neutral species.

  6. nIFTy galaxy cluster simulations - V. Investigation of the cluster infall region

    NASA Astrophysics Data System (ADS)

    Arthur, Jake; Pearce, Frazer R.; Gray, Meghan E.; Elahi, Pascal J.; Knebe, Alexander; Beck, Alexander M.; Cui, Weiguang; Cunnama, Daniel; Davé, Romeel; February, Sean; Huang, Shuiyao; Katz, Neal; Kay, Scott T.; McCarthy, Ian G.; Murante, Giuseppe; Perret, Valentin; Power, Chris; Puchwein, Ewald; Saro, Alexandro; Sembolini, Federico; Teyssier, Romain; Yepes, Gustavo

    2017-01-01

    We examine the properties of the galaxies and dark matter haloes residing in the cluster infall region surrounding the simulated Λ cold dark matter galaxy cluster studied by Elahi et al. at z = 0. The 1.1 × 1015 h-1 M⊙ galaxy cluster has been simulated with eight different hydrodynamical codes containing a variety of hydrodynamic solvers and sub-grid schemes. All models completed a dark-matter-only, non-radiative and full-physics run from the same initial conditions. The simulations contain dark matter and gas with mass resolution mDM = 9.01 × 108 h-1 M⊙ and mgas = 1.9 × 108 h-1 M⊙, respectively. We find that the synthetic cluster is surrounded by clear filamentary structures that contain ˜60 per cent of haloes in the infall region with mass ˜1012.5-1014 h-1 M⊙, including 2-3 group-sized haloes (>1013 h-1 M⊙). However, we find that only ˜10 per cent of objects in the infall region are sub-haloes residing in haloes, which may suggest that there is not much ongoing pre-processing occurring in the infall region at z = 0. By examining the baryonic content contained within the haloes, we also show that the code-to-code scatter in stellar fraction across all halo masses is typically ˜2 orders of magnitude between the two most extreme cases, and this is predominantly due to the differences in sub-grid schemes and calibration procedures that each model uses. Models that do not include active galactic nucleus feedback typically produce too high stellar fractions compared to observations by at least ˜1 order of magnitude.

  7. REGIONAL-SCALE WIND FIELD CLASSIFICATION EMPLOYING CLUSTER ANALYSIS

    SciTech Connect

    Glascoe, L G; Glaser, R E; Chin, H S; Loosmore, G A

    2004-06-17

    The classification of time-varying multivariate regional-scale wind fields at a specific location can assist event planning as well as consequence and risk analysis. Further, wind field classification involves data transformation and inference techniques that effectively characterize stochastic wind field variation. Such a classification scheme is potentially useful for addressing overall atmospheric transport uncertainty and meteorological parameter sensitivity issues. Different methods to classify wind fields over a location include the principal component analysis of wind data (e.g., Hardy and Walton, 1978) and the use of cluster analysis for wind data (e.g., Green et al., 1992; Kaufmann and Weber, 1996). The goal of this study is to use a clustering method to classify the winds of a gridded data set, i.e, from meteorological simulations generated by a forecast model.

  8. Hartree-Fock calculation of the differential photoionization cross sections of small Li clusters

    SciTech Connect

    Galitskiy, S. A.; Artemyev, A. N.; Jänkälä, K.; Lagutin, B. M.; Demekhin, Ph. V.

    2015-01-21

    Cross sections and angular distribution parameters for the single-photon ionization of all electron orbitals of Li{sub 2−8} are systematically computed in a broad interval of the photoelectron kinetic energies for the energetically most stable geometry of each cluster. Calculations of the partial photoelectron continuum waves in clusters are carried out by the single center method within the Hartree-Fock approximation. We study photoionization cross sections per one electron and analyze in some details general trends in the photoionization of inner and outer shells with respect to the size and geometry of a cluster. The present differential cross sections computed for Li{sub 2} are in a good agreement with the available theoretical data, whereas those computed for Li{sub 3−8} clusters can be considered as theoretical predictions.

  9. Real-Time MEG Source Localization Using Regional Clustering.

    PubMed

    Dinh, Christoph; Strohmeier, Daniel; Luessi, Martin; Güllmar, Daniel; Baumgarten, Daniel; Haueisen, Jens; Hämäläinen, Matti S

    2015-11-01

    With its millisecond temporal resolution, Magnetoencephalography (MEG) is well suited for real-time monitoring of brain activity. Real-time feedback allows the adaption of the experiment to the subject's reaction and increases time efficiency by shortening acquisition and off-line analysis. Two formidable challenges exist in real-time analysis: the low signal-to-noise ratio (SNR) and the limited time available for computations. Since the low SNR reduces the number of distinguishable sources, we propose an approach which downsizes the source space based on a cortical atlas and allows to discern the sources in the presence of noise. Each cortical region is represented by a small set of dipoles, which is obtained by a clustering algorithm. Using this approach, we adapted dynamic statistical parametric mapping for real-time source localization. In terms of point spread and crosstalk between regions the proposed clustering technique performs better than selecting spatially evenly distributed dipoles. We conducted real-time source localization on MEG data from an auditory experiment. The results demonstrate that the proposed real-time method localizes sources reliably in the superior temporal gyrus. We conclude that real-time source estimation based on MEG is a feasible, useful addition to the standard on-line processing methods, and enables feedback based on neural activity during the measurements.

  10. Real-Time MEG Source Localization using Regional Clustering

    PubMed Central

    Dinh, Christoph; Strohmeier, Daniel; Luessi, Martin; Güllmar, Daniel; Baumgarten, Daniel; Haueisen, Jens; Hämäläinen, Matti S.

    2015-01-01

    With its millisecond temporal resolution, Magnetoencephalography (MEG) is well suited for real-time monitoring of brain activity. Real-time feedback allows the adaption of the experiment to the subject’s reaction and increases time efficiency by shortening acquisition and offline analysis. Two formidable challenges exist in real-time analysis: the low signal-to-noise ratio (SNR) and the limited time available for computations. Since the low SNR reduces the number of distinguishable sources, we propose an approach which downsizes the source space based on a cortical atlas and allows to discern the sources in the presence of noise. Each cortical region is represented by a small set of dipoles, which is obtained by a clustering algorithm. Using this approach, we adapted dynamic statistical parametric mapping (dSPM) for real-time source localization. In terms of point spread and crosstalk between regions the proposed clustering technique performs better than selecting spatially evenly distributed dipoles. We conducted real-time source localization on MEG data from an auditory experiment. The results demonstrate that the proposed real-time method localizes sources reliably in the superior temporal gyrus. We conclude that real-time source estimation based on MEG is a feasible, useful addition to the standard on-line processing methods, and enables feedback based on neural activity during the measurements. PMID:25782980

  11. Fission cross sections in the intermediate energy region

    SciTech Connect

    Lisowski, P.W.; Gavron, A.; Parker, W.E.; Ullmann, J.L.; Balestrini, S.J. ); Carlson, A.D.; Wasson, O.A. ); Hill, N.W. )

    1991-01-01

    Until recently there has been very little cross section data for neutron-induced fission in the intermediate energy region, primarily because no suitable neutron source has existed. At Los Alamos, the WNR target-4 facility provides a high-intensity source of neutrons nearly ideal for fission measurements extending from a fraction of a MeV to several hundred MeV. This paper summarizes the status of fission cross section data in the intermediate energy range (En > 30 MeV) and presents our fission cross section data for {sup 235}U and {sup 238}U compared to intranuclear cascade and statistical model predictions.

  12. The global monsoon division combining the k-means clustering method and low-level cross-equatorial flow

    NASA Astrophysics Data System (ADS)

    Jiang, Ning; Qian, Weihong; Leung, Jeremy Cheuk-Hin

    2016-10-01

    The global monsoon domain has been recently determined utilizing two criteria: difference of local maximum and minimum pentad-mean precipitation rates exceeding 4 mm day-1, and wind reversal of low-level cross-equatorial flow. In this paper, 22 major dry-wet alteration regions under six categories were first derived through the k-means clustering method from the climatological evolution of global precipitation. Considering the seasonal influences of the low-level cross-equatorial flow in these major dry-wet alternation regions, the global monsoon was objectively divided into 16 major regions under five climatological precipitation categories. Nine monsoon regions are distributed between Asia and Australia while four regions are from Africa to the Southwest Indian Ocean and three regions in Americas. Precipitation trends during rainy seasons of 1981-2010 were examined in the 16 monsoon regions. Four regions with decreasing trends of precipitation are located in Africa and the Southwest Indian Ocean while three regions with increasing trends are situated in Americas. Six regions of increasing precipitation trends are concentrated in Asia and the biggest increasing trend is found in south China.

  13. Drama of HII regions: Clustered and Triggered Star Formation

    NASA Astrophysics Data System (ADS)

    Li, Jinzeng; YUAN, Jinghua; LIU, Hongli; Wu, Yuefang; Huang, Yafang

    2015-08-01

    Intense ultraviolet radiation from young massive stars ionizes ambient material leading to the formation of HII regions which have keen impact upon the birth of new stars in the vicinities. The strong radiation may be responsible for the dispersal of molecular clouds to hinder star formation, while the expansion of HII regions would collect neutral material to form dense layers which may be gravitationally unstable to collapse to give birth to new stars.In order to understand the star formation process under the influence of HII regions, we have carried out extensive investigations to well selected star-forming regions which all have been profoundly affected by existing massive O type stars. On the basis of multi-wavelength data from mid-infrared to millimeter collected using Spitzer, Herschel, and ground based radio telescope, the physical status of interstellar medium and star formation in these regions have been revealed. Clustered and sequential star formation have been detected toward well known HII regions, such as IC1396 and Sh-155. In a relatively large infrared dust bubble, active star formation is undergoing and the shell is still expanding. Socked features and signs of triggered star formation have been tentatively detected in a relatively small bubble. The dense cores in the Rosette Molecular Complex detected at 1.1 mm using SMA have been speculated to have a likely triggered origin according to their spatial distribution. Although some observational results have been obtained, more efforts are necessary to reach trustworthy conclusions. And more regions will be extensively explored based on multi-wavelength observations, especially the data collected using the Herschel Space Observatory.

  14. Complete four-photon cluster-state analyzer based on cross-Kerr nonlinearity

    NASA Astrophysics Data System (ADS)

    Wang, Zhi-Hui; Zhu, Long; Su, Shi-Lei; Guo, Qi; Cheng, Liu-Yong; Zhu, Ai-Dong; Zhang, Shou

    2013-09-01

    We propose a method to construct an optical cluster-state analyzer based on cross-Kerr nonlinearity combined with linear optics elements. In the scheme, we employ two four-qubit parity gates and the controlled phase gate (CPG) from only the cross-Kerr nonlinearity and show that all the orthogonal four-qubit cluster states can be completely identified. The scheme is significant for the large-scale quantum communication and quantum information processing networks. In addition, the scheme is feasible and deterministic under current experimental conditions.

  15. Photoionization cross section by Stieltjes imaging applied to coupled cluster Lanczos pseudo-spectra

    SciTech Connect

    Cukras, Janusz; Coriani, Sonia; Decleva, Piero; Christiansen, Ove; Norman, Patrick

    2013-09-07

    A recently implemented asymmetric Lanczos algorithm for computing (complex) linear response functions within the coupled cluster singles (CCS), coupled cluster singles and iterative approximate doubles (CC2), and coupled cluster singles and doubles (CCSD) is coupled to a Stieltjes imaging technique in order to describe the photoionization cross section of atoms and molecules, in the spirit of a similar procedure recently proposed by Averbukh and co-workers within the Algebraic Diagrammatic Construction approach. Pilot results are reported for the atoms He, Ne, and Ar and for the molecules H{sub 2}, H{sub 2}O, NH{sub 3}, HF, CO, and CO{sub 2}.

  16. Photoionization cross section by Stieltjes imaging applied to coupled cluster Lanczos pseudo-spectra.

    PubMed

    Cukras, Janusz; Coriani, Sonia; Decleva, Piero; Christiansen, Ove; Norman, Patrick

    2013-09-07

    A recently implemented asymmetric Lanczos algorithm for computing (complex) linear response functions within the coupled cluster singles (CCS), coupled cluster singles and iterative approximate doubles (CC2), and coupled cluster singles and doubles (CCSD) is coupled to a Stieltjes imaging technique in order to describe the photoionization cross section of atoms and molecules, in the spirit of a similar procedure recently proposed by Averbukh and co-workers within the Algebraic Diagrammatic Construction approach. Pilot results are reported for the atoms He, Ne, and Ar and for the molecules H2, H2O, NH3, HF, CO, and CO2.

  17. A coupled-cluster study of photodetachment cross sections of closed-shell anions

    SciTech Connect

    Cukras, Janusz; Decleva, Piero; Coriani, Sonia

    2014-11-07

    We investigate the performance of Stieltjes Imaging applied to Lanczos pseudo-spectra generated at the coupled cluster singles and doubles, coupled cluster singles and approximate iterative doubles and coupled cluster singles levels of theory in modeling the photodetachment cross sections of the closed shell anions H{sup −}, Li{sup −}, Na{sup −}, F{sup −}, Cl{sup −}, and OH{sup −}. The accurate description of double excitations is found to play a much more important role than in the case of photoionization of neutral species.

  18. Scale size and life time of energy conversion regions observed by Cluster in the plasma sheet

    NASA Astrophysics Data System (ADS)

    Hamrin, M.; Norqvist, P.; Marghitu, O.; Vaivads, A.; Klecker, B.; Kistler, L. M.; Dandouras, I.

    2009-11-01

    In this article, and in a companion paper by Hamrin et al. (2009) [Occurrence and location of concentrated load and generator regions observed by Cluster in the plasma sheet], we investigate localized energy conversion regions (ECRs) in Earth's plasma sheet. From more than 80 Cluster plasma sheet crossings (660 h data) at the altitude of about 15-20 RE in the summer and fall of 2001, we have identified 116 Concentrated Load Regions (CLRs) and 35 Concentrated Generator Regions (CGRs). By examining variations in the power density, E·J, where E is the electric field and J is the current density obtained by Cluster, we have estimated typical values of the scale size and life time of the CLRs and the CGRs. We find that a majority of the observed ECRs are rather stationary in space, but varying in time. Assuming that the ECRs are cylindrically shaped and equal in size, we conclude that the typical scale size of the ECRs is 2 RE≲ΔSECR≲5 RE. The ECRs hence occupy a significant portion of the mid altitude plasma sheet. Moreover, the CLRs appear to be somewhat larger than the CGRs. The life time of the ECRs are of the order of 1-10 min, consistent with the large scale magnetotail MHD simulations of Birn and Hesse (2005). The life time of the CGRs is somewhat shorter than for the CLRs. On time scales of 1-10 min, we believe that ECRs rise and vanish in significant regions of the plasma sheet, possibly oscillating between load and generator character. It is probable that at least some of the observed ECRs oscillate energy back and forth in the plasma sheet instead of channeling it to the ionosphere.

  19. Choosing appropriate analysis methods for cluster randomised cross-over trials with a binary outcome.

    PubMed

    Morgan, Katy E; Forbes, Andrew B; Keogh, Ruth H; Jairath, Vipul; Kahan, Brennan C

    2017-01-30

    In cluster randomised cross-over (CRXO) trials, clusters receive multiple treatments in a randomised sequence over time. In such trials, there is usual correlation between patients in the same cluster. In addition, within a cluster, patients in the same period may be more similar to each other than to patients in other periods. We demonstrate that it is necessary to account for these correlations in the analysis to obtain correct Type I error rates. We then use simulation to compare different methods of analysing a binary outcome from a two-period CRXO design. Our simulations demonstrated that hierarchical models without random effects for period-within-cluster, which do not account for any extra within-period correlation, performed poorly with greatly inflated Type I errors in many scenarios. In scenarios where extra within-period correlation was present, a hierarchical model with random effects for cluster and period-within-cluster only had correct Type I errors when there were large numbers of clusters; with small numbers of clusters, the error rate was inflated. We also found that generalised estimating equations did not give correct error rates in any scenarios considered. An unweighted cluster-level summary regression performed best overall, maintaining an error rate close to 5% for all scenarios, although it lost power when extra within-period correlation was present, especially for small numbers of clusters. Results from our simulation study show that it is important to model both levels of clustering in CRXO trials, and that any extra within-period correlation should be accounted for. Copyright © 2016 John Wiley & Sons, Ltd.

  20. XMM-Newton and Chandra cross-calibration using HIFLUGCS galaxy clusters . Systematic temperature differences and cosmological impact

    NASA Astrophysics Data System (ADS)

    Schellenberger, G.; Reiprich, T. H.; Lovisari, L.; Nevalainen, J.; David, L.

    2015-03-01

    Context. Robust X-ray temperature measurements of the intracluster medium (ICM) of galaxy clusters require an accurate energy-dependent effective area calibration. Since the hot gas X-ray emission of galaxy clusters does not vary on relevant timescales, they are excellent cross-calibration targets. Moreover, cosmological constraints from clusters rely on accurate gravitational mass estimates, which in X-rays strongly depend on cluster gas temperature measurements. Therefore, systematic calibration differences may result in biased, instrument-dependent cosmological constraints. This is of special interest in light of the tension between the Planck results of the primary temperature anisotropies of the cosmic microwave background (CMB) and Sunyaev-Zel'dovich-plus-X-ray cluster-count analyses. Aims: We quantify in detail the systematics and uncertainties of the cross-calibration of the effective area between five X-ray instruments, EPIC-MOS1/MOS2/PN onboard XMM-Newton and ACIS-I/S onboard Chandra, and the influence on temperature measurements. Furthermore, we assess the impact of the cross-calibration uncertainties on cosmology. Methods: Using the HIFLUGCS sample, consisting of the 64 X-ray brightest galaxy clusters, we constrain the ICM temperatures through spectral fitting in the same, mostly isothermal regions and compare the different instruments. We use the stacked residual ratio method to evaluate the cross-calibration uncertainties between the instruments as a function of energy. Our work is an extension to a previous one using X-ray clusters by the International Astronomical Consortium for High Energy Calibration (IACHEC) and is carried out in the context of IACHEC. Results: Performing spectral fitting in the full energy band, (0.7-7) keV, as is typical of the analysis of cluster spectra, we find that best-fit temperatures determined with XMM-Newton/EPIC are significantly lower than Chandra/ACIS temperatures. This confirms the previous IACHEC results obtained

  1. Identification of the cluster control region for the protocadherin-beta genes located beyond the protocadherin-gamma cluster.

    PubMed

    Yokota, Shinnichi; Hirayama, Teruyoshi; Hirano, Keizo; Kaneko, Ryosuke; Toyoda, Shunsuke; Kawamura, Yoshimi; Hirabayashi, Masumi; Hirabayashi, Takahiro; Yagi, Takeshi

    2011-09-09

    The clustered protocadherins (Pcdhs), Pcdh-α, -β, and -γ, are transmembrane proteins constituting a subgroup of the cadherin superfamily. Each Pcdh cluster is arranged in tandem on the same chromosome. Each of the three Pcdh clusters shows stochastic and combinatorial expression in individual neurons, thus generating a hugely diverse set of possible cell surface molecules. Therefore, the clustered Pcdhs are candidates for determining neuronal molecular diversity. Here, we showed that the targeted deletion of DNase I hypersensitive (HS) site HS5-1, previously identified as a Pcdh-α regulatory element in vitro, affects especially the expression of specific Pcdh-α isoforms in vivo. We also identified a Pcdh-β cluster control region (CCR) containing six HS sites (HS16, 17, 17', 18, 19, and 20) downstream of the Pcdh-γ cluster. This CCR comprehensively activates the expression of the Pcdh-β gene cluster in cis, and its deletion dramatically decreases their expression levels. Deleting the CCR nonuniformly down-regulates some Pcdh-γ isoforms and does not affect Pcdh-α expression. Thus, the CCR effect extends beyond the 320-kb region containing the Pcdh-γ cluster to activate the upstream Pcdh-β genes. Thus, we concluded that the CCR is a highly specific regulatory unit for Pcdh-β expression on the clustered Pcdh genomic locus. These findings suggest that each Pcdh cluster is controlled by distinct regulatory elements that activate their expression and that the stochastic gene regulation of the clustered Pcdhs is controlled by the complex chromatin architecture of the clustered Pcdh locus.

  2. Scalable Integrated Region-Based Image Retrieval Using IRM and Statistical Clustering.

    ERIC Educational Resources Information Center

    Wang, James Z.; Du, Yanping

    Statistical clustering is critical in designing scalable image retrieval systems. This paper presents a scalable algorithm for indexing and retrieving images based on region segmentation. The method uses statistical clustering on region features and IRM (Integrated Region Matching), a measure developed to evaluate overall similarity between images…

  3. Photoabsorption cross section of acetylene in the EUV region

    NASA Technical Reports Server (NTRS)

    Wu, C. Y. R.; Judge, D. L.

    1985-01-01

    The measurement of the absolute photoabsorption cross sections of C2H2 in the 175-740 A region by means of a double ionization chamber is reported. The continuum background source is the synchrotron radiation emitted by the Wisconsin 240 MeV electron storage ring. It is found that the cross sections range from 2 to a maximum of 36 Mb. Two new Rydberg series are identified and the cross section data are applied in the analysis of various sum rules. From the rules, it is shown that the data of C2H2 in the 580-1088 A range may be too low, while the measured ionization transition moment may be too high.

  4. Epidemiology of La Crosse Virus Emergence, Appalachia Region, United States

    PubMed Central

    Agusto, Folashade; Calabrese, Justin M.; Muturi, Ephantus J.; Fagan, William F.

    2016-01-01

    La Crosse encephalitis is a viral disease that has emerged in new locations across the Appalachian region of the United States. Conventional wisdom suggests that ongoing emergence of La Crosse virus (LACV) could stem from the invasive Asian tiger (Aedes albopictus) mosquito. Efforts to prove this, however, are complicated by the numerous transmission routes and species interactions involved in LACV dynamics. To analyze LACV transmission by Asian tiger mosquitoes, we constructed epidemiologic models. These models accurately predict empirical infection rates. They do not, however, support the hypothesis that Asian tiger mosquitoes are responsible for the recent emergence of LACV at new foci. Consequently, we conclude that other factors, including different invasive mosquitoes, changes in climate variables, or changes in wildlife densities, should be considered as alternative explanations for recent increases in La Crosse encephalitis. PMID:27767009

  5. The 2mrad Crossing Angle Interaction Region and Extraction Line

    SciTech Connect

    Appleby, R.; U., Manchester; Angal-Kalinin, D.; Dadoun, O.; Bambade, P.; Parker, B.; Keller, L.; Moffeit, K.; Nosochkov, Y.; Seryi, A.; Spencer, C.; Carter, J.; Royal Holloway, U.of London; Napoly, O.; /DAPNIA, Saclay

    2006-07-12

    A complete optics design for the 2mrad crossing angle interaction region and extraction line was presented at Snowmass 2005. Since this time, the design task force has been working on developing and improving the performance of the extraction line. The work has focused on optimizing the final doublet parameters and on reducing the power losses resulting from the disrupted beam transport. In this paper, the most recent status of the 2mrad layout and the corresponding performance are presented.

  6. 75 FR 40856 - Federal Register Meeting Notice; Webinar About Regional Innovation Clusters RFP

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-14

    ... small businesses in the cluster area and industries. SBA intends to make multiple fixed-price contract... ADMINISTRATION Federal Register Meeting Notice; Webinar About Regional Innovation Clusters RFP AGENCY: U.S. Small... Clusters (RIC) Request for Proposals (RFP) No. SBAHQ-10-R-0021. SUMMARY: The SBA is issuing this notice...

  7. Cross-domain, soft-partition clustering with diversity measure and knowledge reference

    PubMed Central

    Qian, Pengjiang; Sun, Shouwei; Jiang, Yizhang; Su, Kuan-Hao; Ni, Tongguang; Wang, Shitong; Muzic, Raymond F.

    2016-01-01

    Conventional, soft-partition clustering approaches, such as fuzzy c-means (FCM), maximum entropy clustering (MEC) and fuzzy clustering by quadratic regularization (FC-QR), are usually incompetent in those situations where the data are quite insufficient or much polluted by underlying noise or outliers. In order to address this challenge, the quadratic weights and Gini-Simpson diversity based fuzzy clustering model (QWGSD-FC), is first proposed as a basis of our work. Based on QWGSD-FC and inspired by transfer learning, two types of cross-domain, soft-partition clustering frameworks and their corresponding algorithms, referred to as type-I/type-II knowledge-transfer-oriented c-means (TI-KT-CM and TII-KT-CM), are subsequently presented, respectively. The primary contributions of our work are four-fold: (1) The delicate QWGSD-FC model inherits the most merits of FCM, MEC and FC-QR. With the weight factors in the form of quadratic memberships, similar to FCM, it can more effectively calculate the total intra-cluster deviation than the linear form recruited in MEC and FC-QR. Meanwhile, via Gini-Simpson diversity index, like Shannon entropy in MEC, and equivalent to the quadratic regularization in FC-QR, QWGSD-FC is prone to achieving the unbiased probability assignments, (2) owing to the reference knowledge from the source domain, both TI-KT-CM and TII-KT-CM demonstrate high clustering effectiveness as well as strong parameter robustness in the target domain, (3) TI-KT-CM refers merely to the historical cluster centroids, whereas TII-KT-CM simultaneously uses the historical cluster centroids and their associated fuzzy memberships as the reference. This indicates that TII-KT-CM features more comprehensive knowledge learning capability than TI-KT-CM and TII-KT-CM consequently exhibits more perfect cross-domain clustering performance and (4) neither the historical cluster centroids nor the historical cluster centroid based fuzzy memberships involved in TI-KT-CM or TII

  8. The Awareness and Educational Status on Oral Health of Elite Athletes: A Cross-Sectional Study with Cluster Analysis

    ERIC Educational Resources Information Center

    Ozgur, Bahar Odabas

    2016-01-01

    In this cross-sectional survey, this study aimed to determine the factors associated with oral health of elite athletes and to determine the clustering tendency of the variables by dendrogram, and to determine the relationship between predefined clusters and see how these clusters can converge. A total of 97 elite (that is, top-level performing)…

  9. Mapping hotspots of threatened species traded in bushmeat markets in the Cross-Sanaga rivers region.

    PubMed

    Fa, John E; Farfán, Miguel Angel; Marquez, Ana Luz; Duarte, Jesús; Nackoney, Janet; Hall, Amy; Dupain, Jef; Seymour, Sarah; Johnson, Paul J; MacDonald, David W; Vargas, J Mario

    2014-02-01

    Bushmeat markets exist in many countries in West and Central Africa, and data on species sold can be used to detect patterns of wildlife trade in a region. We surveyed 89 markets within the Cross-Sanaga rivers region, West Africa. In each market, we counted the number of carcasses of each taxon sold. During a 6-month period (7594 market days), 44 mammal species were traded. Thirteen species were on the International Union for Conservation of Nature (IUCN) Red List or protected under national legislation, and at least 1 threatened species was traded in 88 of the 89 markets. We used these data to identify market groups that traded similar species assemblages. Using cluster analyses, we detected 8 market groups that were also geographically distinct. Market groups differed in the diversity of species, evenness of species, and dominant, prevalent, and characteristic species traded. We mapped the distribution of number of threatened species traded across the study region. Most threatened species were sold in markets nearest 2 national parks, Korup National Park in Cameroon and Cross River in Nigeria. To assess whether the threatened-species trade hotspots coincided with the known ranges of these species, we mapped the overlap of all threatened species traded. Markets selling more threatened species overlapped with those regions that had higher numbers of these. Our study can provide wildlife managers in the region with better tools to discern zones within which to focus policing efforts and reduce threats to species that are threatened by the bushmeat trade.

  10. Finding common task-related regions in fMRI data from multiple subjects by periodogram clustering and clustering ensemble.

    PubMed

    Ye, Jun; Li, Yehua; Lazar, Nicole A; Schaeffer, David J; McDowell, Jennifer E

    2016-07-10

    We propose an innovative and practically relevant clustering method to find common task-related brain regions among different subjects who respond to the same set of stimuli. Using functional magnetic resonance imaging (fMRI) time series data, we first cluster the voxels within each subject on a voxel by voxel basis. To extract signals out of noisy data, we estimate a new periodogram at each voxel using multi-tapering and low-rank spline smoothing and then use the periodogram as the main feature for clustering. We apply a divisive hierarchical clustering algorithm to the estimated periodograms within a single subject and identify the task-related region as the cluster of voxels that have periodograms with a peak frequency matching that of the stimulus sequence. Finally, we apply a machine learning technique called clustering ensemble to find common task-related regions across different subjects. The efficacy of the proposed approach is illustrated via a simulation study and a real fMRI data set. Copyright © 2016 John Wiley & Sons, Ltd.

  11. 75 FR 17700 - Energy Efficient Building Systems Regional Innovation Cluster Initiative-Joint Federal Funding...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-07

    ... organizations, and other interested parties to learn more about the Joint Federal Funding Opportunity... the regional innovation cluster (the ``Energy Regional Innovation Cluster'' or ``E-RIC'') and will... you have registered, you will be sent an e-mail to enable your Workforce3one account. You will need...

  12. Young star clusters in the circumnuclear region of NGC 2110

    SciTech Connect

    Durré, Mark; Mould, Jeremy

    2014-03-20

    High-resolution observations in the near infrared show star clusters around the active galactic nucleus (AGN) of the Seyfert 1 NGC 2110, along with a 90 × 35 pc bar of shocked gas material around its nucleus. These are seen for the first time in our imaging and gas kinematics of the central 100 pc with the Keck OSIRIS instrument with adaptive optics. Each of these clusters is two to three times brighter than the Arches cluster close to the center of the Milky Way. The core star formation rate is 0.3 M {sub ☉} yr{sup –1}. The photoionized gas (He I) dynamics imply an enclosed mass of 3-4 × 10{sup 8} M {sub ☉}. These observations demonstrate the physical linkage between AGN feedback, which triggers star formation in massive clusters, and the resulting stellar (and supernovae) winds, which cause the observed [Fe II] emission and feed the black hole.

  13. Dissociative recombination of water cluster ions with free electrons: Cross sections and branching ratios

    NASA Astrophysics Data System (ADS)

    Öjekull, J.; Andersson, P. U.; Pettersson, J. B. C.; Marković, N.; Thomas, R. D.; Al Khalili, A.; Ehlerding, A.; Österdahl, F.; af Ugglas, M.; Larsson, M.; Danared, H.; Källberg, A.

    2008-01-01

    Dissociative recombination (DR) of water cluster ions H+(H2O)n (n=4-6) with free electrons has been studied at the heavy-ion storage ring CRYRING (Manne Siegbahn Laboratory, Stockholm University). For the first time, branching ratios have been determined for the dominating product channels and absolute DR cross sections have been measured in the energy range from 0.001to0.7eV. Dissociative recombination is concluded to result in extensive fragmentation for all three cluster ions, and a maximum number of heavy oxygen-containing fragments is produced with a probability close to unity. The branching ratio results agree with earlier DR studies of smaller water cluster ions where the channel nH2O +H has been observed to dominate and where energy transfer to internal degrees of freedom has been concluded to be highly efficient. The absolute DR cross sections for H+(H2O)n (n=4-6) decrease monotonically with increasing energy with an energy dependence close to E-1 in the lower part of the energy range and a faster falloff at higher energies, in agreement with the behavior of other studied heavy ions. The cross section data have been used to calculate DR rate coefficients in the temperature range of 10-2000K. The results from storage ring experiments with water cluster ions are concluded to partly confirm the earlier results from afterglow experiments. The DR rate coefficients for H+(H2O)n (n=1-6) are in general somewhat lower than reported from afterglow experiments. The rate coefficient tends to increase with increasing cluster size, but not in the monotonic way that has been reported from afterglow experiments. The needs for further experimental studies and for theoretical models that can be used to predict the DR rate of polyatomic ions are discussed.

  14. Dissociative recombination of water cluster ions with free electrons: cross sections and branching ratios.

    PubMed

    Ojekull, J; Andersson, P U; Pettersson, J B C; Marković, N; Thomas, R D; Al Khalili, A; Ehlerding, A; Osterdahl, F; af Ugglas, M; Larsson, M; Danared, H; Källberg, A

    2008-01-28

    Dissociative recombination (DR) of water cluster ions H(+)(H(2)O)(n) (n=4-6) with free electrons has been studied at the heavy-ion storage ring CRYRING (Manne Siegbahn Laboratory, Stockholm University). For the first time, branching ratios have been determined for the dominating product channels and absolute DR cross sections have been measured in the energy range from 0.001 to 0.7 eV. Dissociative recombination is concluded to result in extensive fragmentation for all three cluster ions, and a maximum number of heavy oxygen-containing fragments is produced with a probability close to unity. The branching ratio results agree with earlier DR studies of smaller water cluster ions where the channel nH(2)O+H has been observed to dominate and where energy transfer to internal degrees of freedom has been concluded to be highly efficient. The absolute DR cross sections for H(+)(H(2)O)(n) (n=4-6) decrease monotonically with increasing energy with an energy dependence close to E(-1) in the lower part of the energy range and a faster falloff at higher energies, in agreement with the behavior of other studied heavy ions. The cross section data have been used to calculate DR rate coefficients in the temperature range of 10-2000 K. The results from storage ring experiments with water cluster ions are concluded to partly confirm the earlier results from afterglow experiments. The DR rate coefficients for H(+)(H(2)O)(n) (n=1-6) are in general somewhat lower than reported from afterglow experiments. The rate coefficient tends to increase with increasing cluster size, but not in the monotonic way that has been reported from afterglow experiments. The needs for further experimental studies and for theoretical models that can be used to predict the DR rate of polyatomic ions are discussed.

  15. Cross-correlating the γ-ray Sky with Catalogs of Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Branchini, Enzo; Camera, Stefano; Cuoco, Alessandro; Fornengo, Nicolao; Regis, Marco; Viel, Matteo; Xia, Jun-Qing

    2017-01-01

    We report the detection of a cross-correlation signal between Fermi Large Area Telescope diffuse γ-ray maps and catalogs of clusters. In our analysis, we considered three different catalogs: WHL12, redMaPPer, and PlanckSZ. They all show a positive correlation with different amplitudes, related to the average mass of the objects in each catalog, which also sets the catalog bias. The signal detection is confirmed by the results of a stacking analysis. The cross-correlation signal extends to rather large angular scales, around 1°, that correspond, at the typical redshift of the clusters in these catalogs, to a few to tens of megaparsecs, i.e., the typical scale-length of the large-scale structures in the universe. Most likely this signal is contributed by the cumulative emission from active galactic nuclei (AGNs) associated with the filamentary structures that converge toward the high peaks of the matter density field in which galaxy clusters reside. In addition, our analysis reveals the presence of a second component, more compact in size and compatible with a point-like emission from within individual clusters. At present, we cannot distinguish between the two most likely interpretations for such a signal, i.e., whether it is produced by AGNs inside clusters or if it is a diffuse γ-ray emission from the intracluster medium. We argue that this latter, intriguing, hypothesis might be tested by applying this technique to a low-redshift large-mass cluster sample.

  16. Cluster Observations of Channels of Enhanced Convection Velocity in the Ring Current Region

    NASA Astrophysics Data System (ADS)

    Puhl-Quinn, P. A.; Foerster, M.; Labelle, J.; Linder, J.; Matsui, H.; Treumann, R.

    2003-12-01

    For decades, spacecraft-borne instruments have detected enhanced convection features in the duskside and premidnight subauroral region, variously known as polarization jet [Galperin et al., 1973] or subauroral ion drifts (SAID) [Spiro et al., 1979]. We report Cluster observations of this phenomenon, detected with the electron drift instrument (EDI) which uses a novel particle-detection method to measure electric fields in the plane perpendicular to the magnetic field. We have identified enhanced convection velocity striations within the dusk-side ring current region. Such striations with durations 1-5 minutes were observed in AMPTE/IRM data [LaBelle et al., 1988] and also may be the source of fine features observed recently in ground-based radar observations of SAID [Erickson et al., 2002]. Cluster, due to its more polar orbit, finds them on time scales of tens of minutes implying that the channels are extended along magnetic flux tubes. A survey of Cluster/EDI data from February, 2001 until July, 2003 was performed, using data from 14 to 24 hours local time, from 60-69 degrees invariant latitude, and for Kp > 4. Enhanced electric fields were defined as those in the anti-corotation direction (westward) with amplitude exceeding twice the corotation speed. The data show a tendency for the enhanced electric fields to occur at lower latitudes in premidnight/midnight local time than on the duskside, consistent with previous observations. Many previous observations report widths as narrow as 0.1 degrees for SAID events, and for example the 1-5 minute crossing times at IRM imply striation widths on the order of 1000-2000 km. The variable separations of the Cluster spacecraft over the multi-year data set provides a unique opportunity to improve the determination of this width. In this paper, we elaborate about statistical properties, theoretical implications, and association with the SAPS (sub-auroral polarization streams) and SAID phenomena. Erickson, P.J., et al

  17. Cross-Genome Clustering of Human and C. elegans G-Protein Coupled Receptors

    PubMed Central

    Nagarathnam, Balasubramanian; Kalaimathy, Singaravelu; Balakrishnan, Veluchamy; Sowdhamini, Ramanathan

    2012-01-01

    G-protein coupled receptors (GPCRs) are one of the largest groups of membrane proteins and are popular drug targets. The work reported here attempts to perform cross-genome phylogeny on GPCRs from two widely different taxa, human versus C. elegans genomes and to address the issues on evolutionary plasticity, to identify functionally related genes, orthologous relationship, and ligand binding properties through effective bioinformatic approaches. Through RPS blast around 1106 nematode GPCRs were given chance to associate with previously established 8 types of human GPCR profiles at varying E-value thresholds and resulted 32 clusters were illustrating co-clustering and class-specific retainsionship. In the significant thresholds, 81% of the C. elegans GPCRs were associated with 32 clusters and 27 C. elegans GPCRs (2%) inferred for orthology. 177 hypothetical proteins were observed in cluster association and could be reliably associated with one of 32 clusters. Several nematode-specific GPCR clades were observed suggesting lineage-specific functional recruitment in response to environment. PMID:22807621

  18. Cross-correlation Weak Lensing of SDSS Galaxy Clusters I: Measurements

    SciTech Connect

    Sheldon, Erin S.; Johnston, David E.; Scranton, Ryan; Koester, Ben P.; McKay, Timothy A.; Oyaizu, Hiroaki; Cunha, Carlos; Lima, Marcos; Lin, Huan; Frieman, Joshua A.; Wechsler, Risa H.; Annis, James; Mandelbaum, Rachel; Bahcall, Neta A.; Fukugita, Masataka

    2007-09-28

    This is the first in a series of papers on the weak lensing effect caused by clusters of galaxies in Sloan Digital Sky Survey. The photometrically selected cluster sample, known as MaxBCG, includes {approx}130,000 objects between redshift 0.1 and 0.3, ranging in size from small groups to massive clusters. We split the clusters into bins of richness and luminosity and stack the surface density contrast to produce mean radial profiles. The mean profiles are detected over a range of scales, from the inner halo (25 kpc/h) well into the surrounding large scale structure (30 Mpc/h), with a significance of 15 to 20 in each bin. The signal over this large range of scales is best interpreted in terms of the cluster-mass cross-correlation function. We pay careful attention to sources of systematic error, correcting for them where possible and bounding them where not. We find that the profiles scale strongly with richness and luminosity. We find the signal within a given richness bin depends upon luminosity, suggesting that luminosity is more closely correlated with mass than galaxy counts. We split the samples by redshift but detect no significant evolution. The profiles are not well described by power laws. In a subsequent series of papers we invert the profiles to three-dimensional mass profiles, show that they are well fit by a halo model description, measure mass-to-light ratios and provide a cosmological interpretation.

  19. Central San Juan caldera cluster: regional volcanic framework

    USGS Publications Warehouse

    Lipman, Peter W.

    2000-01-01

    Eruption of at least 8800 km3 of dacitic-rhyolitic magma as 9 major ash-slow sheets (individually 150-5000 km3) was accompanied by recurrent caldera subsidence between 28.3 and about 26.5 Ma in the central San Juan Mountains, Colorado. Voluminous andesitic-decitic lavas and breccias were erupted from central volcanoes prior to the ash-flow eruptions, and similar lava eruptions continued within and adjacent to the calderas during the period of explosive volcanism, making the central San Juan caldera cluster an exceptional site for study of caldera-related volcanic processes. Exposed calderas vary in size from 10 to 75 km in maximum diameter, the largest calderas being associated with the most voluminous eruptions. After collapse of the giant La Garita caldera during eruption if the Fish Canyon Tuff at 17.6 Ma, seven additional explosive eruptions and calderas formed inside the La Garita depression within about 1 m.y. Because of the nested geometry, maximum loci of recurrently overlapping collapse events are inferred to have subsided as much as 10-17 km, far deeper than the roof of the composite subvolcanic batholith defined by gravity data, which represents solidified caldera-related magma bodies. Erosional dissection to depths of as much as 1.5 km, although insufficient to reach the subvolcanic batholith, has exposed diverse features of intracaldera ash-flow tuff and interleaved caldera-collapse landslide deposits that accumulated to multikilometer thickness within concurrently subsiding caldera structures. The calderas display a variety of postcollapse resurgent uplift structures, and caldera-forming events produced complex fault geometries that localized late mineralization, including the epithermal base- and precious-metal veins of the well-known Creede mining district. Most of the central San Juan calderas have been deeply eroded, and their identification is dependent on detailed geologic mapping. In contrast, the primary volcanic morphology of the

  20. Cross-Layer Cluster-Based Energy-Efficient Protocol for Wireless Sensor Networks

    PubMed Central

    Mammu, Aboobeker Sidhik Koyamparambil; Hernandez-Jayo, Unai; Sainz, Nekane; de la Iglesia, Idoia

    2015-01-01

    Recent developments in electronics and wireless communications have enabled the improvement of low-power and low-cost wireless sensors networks (WSNs). One of the most important challenges in WSNs is to increase the network lifetime due to the limited energy capacity of the network nodes. Another major challenge in WSNs is the hot spots that emerge as locations under heavy traffic load. Nodes in such areas quickly drain energy resources, leading to disconnection in network services. In such an environment, cross-layer cluster-based energy-efficient algorithms (CCBE) can prolong the network lifetime and energy efficiency. CCBE is based on clustering the nodes to different hexagonal structures. A hexagonal cluster consists of cluster members (CMs) and a cluster head (CH). The CHs are selected from the CMs based on nodes near the optimal CH distance and the residual energy of the nodes. Additionally, the optimal CH distance that links to optimal energy consumption is derived. To balance the energy consumption and the traffic load in the network, the CHs are rotated among all CMs. In WSNs, energy is mostly consumed during transmission and reception. Transmission collisions can further decrease the energy efficiency. These collisions can be avoided by using a contention-free protocol during the transmission period. Additionally, the CH allocates slots to the CMs based on their residual energy to increase sleep time. Furthermore, the energy consumption of CH can be further reduced by data aggregation. In this paper, we propose a data aggregation level based on the residual energy of CH and a cost-aware decision scheme for the fusion of data. Performance results show that the CCBE scheme performs better in terms of network lifetime, energy consumption and throughput compared to low-energy adaptive clustering hierarchy (LEACH) and hybrid energy-efficient distributed clustering (HEED). PMID:25860073

  1. Cross-layer cluster-based energy-efficient protocol for wireless sensor networks.

    PubMed

    Mammu, Aboobeker Sidhik Koyamparambil; Hernandez-Jayo, Unai; Sainz, Nekane; de la Iglesia, Idoia

    2015-04-09

    Recent developments in electronics and wireless communications have enabled the improvement of low-power and low-cost wireless sensors networks (WSNs). One of the most important challenges in WSNs is to increase the network lifetime due to the limited energy capacity of the network nodes. Another major challenge in WSNs is the hot spots that emerge as locations under heavy traffic load. Nodes in such areas quickly drain energy resources, leading to disconnection in network services. In such an environment, cross-layer cluster-based energy-efficient algorithms (CCBE) can prolong the network lifetime and energy efficiency. CCBE is based on clustering the nodes to different hexagonal structures. A hexagonal cluster consists of cluster members (CMs) and a cluster head (CH). The CHs are selected from the CMs based on nodes near the optimal CH distance and the residual energy of the nodes. Additionally, the optimal CH distance that links to optimal energy consumption is derived. To balance the energy consumption and the traffic load in the network, the CHs are rotated among all CMs. In WSNs, energy is mostly consumed during transmission and reception. Transmission collisions can further decrease the energy efficiency. These collisions can be avoided by using a contention-free protocol during the transmission period. Additionally, the CH allocates slots to the CMs based on their residual energy to increase sleep time. Furthermore, the energy consumption of CH can be further reduced by data aggregation. In this paper, we propose a data aggregation level based on the residual energy of CH and a cost-aware decision scheme for the fusion of data. Performance results show that the CCBE scheme performs better in terms of network lifetime, energy consumption and throughput compared to low-energy adaptive clustering hierarchy (LEACH) and hybrid energy-efficient distributed clustering (HEED).

  2. Health region development from the perspective of system theory - an empirical cross-regional case study.

    PubMed

    Volgger, Michael; Mainil, Tomas; Pechlaner, Harald; Mitas, Ondrej

    2015-01-01

    Governments are increasingly establishing health regions to deal with current challenges of public health service. These regions are seen as instruments to balance public and private stakeholders, and offer health care to regional citizens as well as to medical/health tourists. However, it is still unclear how the development of such health regions as well as their governance may be conceptualized. We apply Luhmann's system theory approach in the context of a cross-regional case study that compares health region developments in the Autonomous Province of Bolzano-South Tyrol (Italy) with particular regard to the Eastern Dolomites and in the province of Zeeland (the Netherlands). We suggest that Luhmann's system theory provides a useful set of criteria to evaluate and judge health region development. Fully developed health regions can be understood as auto-poietic systems. By emphasizing programs, personnel, and communication channels, these case studies illustrate the suitability of the system theory toolset to analyze the governance and spatial embeddedness of health regions. Additionally, the study contributes to literature by indicating that health regions are closely related to identity issues and to decision making in regions.

  3. A cross-species bi-clustering approach to identifying conserved co-regulated genes

    PubMed Central

    Sun, Jiangwen; Jiang, Zongliang; Tian, Xiuchun; Bi, Jinbo

    2016-01-01

    Motivation: A growing number of studies have explored the process of pre-implantation embryonic development of multiple mammalian species. However, the conservation and variation among different species in their developmental programming are poorly defined due to the lack of effective computational methods for detecting co-regularized genes that are conserved across species. The most sophisticated method to date for identifying conserved co-regulated genes is a two-step approach. This approach first identifies gene clusters for each species by a cluster analysis of gene expression data, and subsequently computes the overlaps of clusters identified from different species to reveal common subgroups. This approach is ineffective to deal with the noise in the expression data introduced by the complicated procedures in quantifying gene expression. Furthermore, due to the sequential nature of the approach, the gene clusters identified in the first step may have little overlap among different species in the second step, thus difficult to detect conserved co-regulated genes. Results: We propose a cross-species bi-clustering approach which first denoises the gene expression data of each species into a data matrix. The rows of the data matrices of different species represent the same set of genes that are characterized by their expression patterns over the developmental stages of each species as columns. A novel bi-clustering method is then developed to cluster genes into subgroups by a joint sparse rank-one factorization of all the data matrices. This method decomposes a data matrix into a product of a column vector and a row vector where the column vector is a consistent indicator across the matrices (species) to identify the same gene cluster and the row vector specifies for each species the developmental stages that the clustered genes co-regulate. Efficient optimization algorithm has been developed with convergence analysis. This approach was first validated on

  4. Improving hot region prediction by parameter optimization of density clustering in PPI.

    PubMed

    Hu, Jing; Zhang, Xiaolong

    2016-11-01

    This paper proposed an optimized algorithm which combines density clustering of parameter selection with feature-based classification for hot region prediction. First, all the residues are classified by SVM to remove non-hot spot residues, then density clustering of parameter selection is used to find hot regions. In the density clustering, this paper studies how to select input parameters. There are two parameters radius and density in density-based incremental clustering. We firstly fix density and enumerate radius to find a pair of parameters which leads to maximum number of clusters, and then we fix radius and enumerate density to find another pair of parameters which leads to maximum number of clusters. Experiment results show that the proposed method using both two pairs of parameters provides better prediction performance than the other method, and compare these two predictive results, the result by fixing radius and enumerating density have slightly higher prediction accuracy than that by fixing density and enumerating radius.

  5. MOLECULAR CLUMPS AND INFRARED CLUSTERS IN THE S247, S252, AND BFS52 REGIONS

    SciTech Connect

    Shimoikura, Tomomi; Dobashi, Kazuhito; Saito, Hiro; Nakamura, Fumitaka; Matsumoto, Tomoaki; Nishimura, Atsushi; Kimura, Kimihiro; Onishi, Toshikazu; Ogawa, Hideo

    2013-05-01

    We present results of the observations carried out toward the S247, S252, and BFS52 H II regions with various molecular lines using the 1.85 m radio telescope and the 45 m telescope at Nobeyama Radio Observatory. There are at least 11 young infrared clusters (IR clusters) within the observed region. We found that there are two velocity components in {sup 12}CO (J = 2-1), and also that their spatial distributions show an anti-correlation. The IR clusters are located at their interfaces, suggesting that two distinct clouds with different velocities are colliding with each other, which may have induced the cluster formation. Based on {sup 13}CO (J = 1-0) and C{sup 18}O (J = 1-0) observations, we identified 16 clumps in and around the three H II regions. Eleven of the clumps are associated with the IR clusters and the other five clumps are not associated with any known young stellar objects. We investigated variations in the velocity dispersions of the 16 clumps as a function of the distance from the center of the clusters or the clumps. Clumps with clusters tend to have velocity dispersions that increase with distance from the cluster center, while clumps without clusters show a flat velocity dispersion over the clump extents. A {sup 12}CO outflow has been found in some of the clumps with IR clusters but not in the other clumps, supporting a strong relation of these clumps to the broader velocity dispersion region. We also estimated a mean star formation efficiency of {approx}30% for the clumps with IR clusters in the three H II regions.

  6. Cross-correlation Weak Lensing of SDSS Galaxy Clusters III: Mass-to-light Ratios

    SciTech Connect

    Sheldon, Erin S.; Johnston, David E.; Masjedi, Morad; McKay, Timothy A.; Blanton, Michael R.; Scranton, Ryan; Wechsler, Risa H.; Koester, Ben P.; Hansen, Sarah M.; Frieman, Joshua A.; Annis, James

    2007-09-28

    We present measurements of the excess mass-to-light ratio measured around MaxBCG galaxy clusters observed in the SDSS. This red sequence cluster sample includes objects from small groups with M{sub 200} {approx} 5 x 10{sup 12}h{sup -1}M{sub {circle_dot}} to clusters with M{sub 200} {approx} 5 x 10{sup 15}h{sup -1}M{sub {circle_dot}}. Using cross-correlation weak lensing, we measure the excess mass density profile above the universal mean {Delta}{yields}(r) = {rho}(r) -- {bar {rho}} for clusters in bins of richness and optical luminosity. We also measure the excess {sup 0.25}i-band luminosity density {Delta}{ell}(r) = {ell}(r) -- {bar {ell}}. For both mass and light, we de-project the profiles to produce 3D mass and light profiles over scales from 25h{sup -1} kpc to 22h{sup -1} Mpc. From these profiles we calculate the cumulative excess mass {Delta}M(r) and excess light {Delta}L(r) as a function of separation from the BCG. On small scales, where {rho}(r) >> {bar {rho}}, the integrated mass-to-light profile ({Delta}M/{Delta}L)(r) may be interpreted as the cluster mass-to-light ratio. We find the ({Delta}M/{Delta}L){sub 200}, the mass-to-light ratio within r{sub 200}, scales with cluster mass as a power law with index 0.33{+-}0.02. On large scales, where {rho}(r) {approx} {bar {rho}}, the {Delta}M/{Delta}L approaches an asymptotic value independent of scale or cluster richness. For small groups, the mean ({Delta}M/{Delta}L){sub 200} is much smaller than the asymptotic value, while for large clusters ({Delta}M/{Delta}L)200 is consistent with the asymptotic value. This asymptotic value should be proportional to the mean mass-to-light ratio of the universe {l_angle}M/L{r_angle}. We find {l_angle}M/L{r_angle} b{sup -2}{sub M/L} = 362 {+-} 54h measured in the {sup 0.25}i-bandpass. The parameter b{sup 2}{sub M/L} is primarily a function of the bias of the L {approx}< L* galaxies used as light tracers, and should be of order unity. Multiplying by the luminosity density in

  7. CROSS-CORRELATION WEAK LENSING OF SDSS GALAXY CLUSTERS. III. MASS-TO-LIGHT RATIOS

    SciTech Connect

    Sheldon, Erin S.; Johnston, David E.; Masjedi, Morad; Blanton, Michael R.; McKay, Timothy A.; Scranton, Ryan; Wechsler, Risa H.; Koester, Benjamin P.; Hansen, Sarah M.; Frieman, Joshua A.; Annis, James

    2009-10-01

    We present measurements of the excess mass-to-light ratio (M/L) measured around MaxBCG galaxy clusters observed in the Sloan Digital Sky Survey. This red-sequence cluster sample includes objects from small groups with M {sub 200} approx 5 x 10{sup 12} h {sup -1} M {sub sun} to clusters with M {sub 200} approx 10{sup 15} h {sup -1} M {sub sun}. Using cross-correlation weak lensing, we measure the excess mass density profile above the universal mean DELTArho(r)=rho(r)-rho-bar for clusters in bins of richness and optical luminosity. We also measure the excess luminosity density DELTAl(r)=l(r)-l-bar measured in the z = 0.25 i band. For both mass and light, we de-project the profiles to produce three-dimensional mass and light profiles over scales from 25 h {sup -1} kpc to 22 h {sup -1} Mpc. From these profiles we calculate the cumulative excess mass DELTAM(r) and excess light DELTAL(r) as a function of separation from the BCG. On small scales, where rho(r)>>rho-bar, the integrated mass-to-light profile (DELTAM/DELTAL)(r) may be interpreted as the cluster M/L. We find the (DELTAM/DELTAL){sub 200}, the M/L within r {sub 200}, scales with cluster mass as a power law with index 0.33 +- 0.02. On large scales, where rho(r)approxrho-bar, the DELTAM/DELTAL approaches an asymptotic value independent of cluster richness. For small groups, the mean (DELTAM/DELTAL){sub 200} is much smaller than the asymptotic value, while for large clusters (DELTAM/DELTAL){sub 200} is consistent with the asymptotic value. This asymptotic value should be proportional to the mean M/L of the universe (M/L). We find (M/L)b{sup -2} {sub M/L} = 362 +- 54h (statistical). There is additional uncertainty in the overall calibration at the approx10% level. The parameter b {sup 2} {sub M/L} is primarily a function of the bias of the L approx< L {sub *} galaxies used as light tracers, and should be of order unity. Multiplying by the luminosity density in the same bandpass we find OMEGA {sub m}b{sup -2} {sub M

  8. Dissociative recombination of water cluster ions with free electrons: Cross sections and branching ratios

    SciTech Connect

    Oejekull, J.; Andersson, P. U.; Pettersson, J. B. C.; Markovic, N.; Thomas, R. D.; Al Khalili, A.; Ehlerding, A.; Oesterdahl, F.; Ugglas, M. af; Larsson, M.; Danared, H.; Kaellberg, A.

    2008-01-28

    Dissociative recombination (DR) of water cluster ions H{sup +}(H{sub 2}O){sub n} (n=4-6) with free electrons has been studied at the heavy-ion storage ring CRYRING (Manne Siegbahn Laboratory, Stockholm University). For the first time, branching ratios have been determined for the dominating product channels and absolute DR cross sections have been measured in the energy range from 0.001 to 0.7 eV. Dissociative recombination is concluded to result in extensive fragmentation for all three cluster ions, and a maximum number of heavy oxygen-containing fragments is produced with a probability close to unity. The branching ratio results agree with earlier DR studies of smaller water cluster ions where the channel nH{sub 2}O+H has been observed to dominate and where energy transfer to internal degrees of freedom has been concluded to be highly efficient. The absolute DR cross sections for H{sup +}(H{sub 2}O){sub n} (n=4-6) decrease monotonically with increasing energy with an energy dependence close to E{sup -1} in the lower part of the energy range and a faster falloff at higher energies, in agreement with the behavior of other studied heavy ions. The cross section data have been used to calculate DR rate coefficients in the temperature range of 10-2000 K. The results from storage ring experiments with water cluster ions are concluded to partly confirm the earlier results from afterglow experiments. The DR rate coefficients for H{sup +}(H{sub 2}O){sub n} (n=1-6) are in general somewhat lower than reported from afterglow experiments. The rate coefficient tends to increase with increasing cluster size, but not in the monotonic way that has been reported from afterglow experiments. The needs for further experimental studies and for theoretical models that can be used to predict the DR rate of polyatomic ions are discussed.

  9. 197Au(n,gamma) Cross Section in the Unresolved Resonance Region

    SciTech Connect

    Lederer, C.; Koehler, Paul Edward

    2011-03-01

    The cross section of the reaction {sup 197}Au(n,{gamma}) was measured with the time-of-flight technique at the n{_}TOF (neutron time-of-flight) facility in the unresolved resonance region between 5 and 400 keV using a pair of C{sub 6}D{sub 6} (where D denotes {sup 2}H) liquid scintillators for the detection of prompt capture {gamma} rays. The results with a total uncertainty of 3.9%-6.7% for a resolution of 20 bins per energy decade show fair agreement with the Evaluated Nuclear Data File Version B-VII.0 (ENDF/B-VII.0), which contains the standard evaluation. The Maxwellian-averaged cross section (MACS) at 30 keV is in excellent agreement with the one according to the ENDF/B-VII.0 evaluation and 4.7% higher than the MACS measured independently by activation technique. Structures in the cross section, which had also been reported earlier, have been interpreted as being due to clusters of resonances.

  10. Au197(n,γ) cross section in the unresolved resonance region

    NASA Astrophysics Data System (ADS)

    Lederer, C.; Colonna, N.; Domingo-Pardo, C.; Gunsing, F.; Käppeler, F.; Massimi, C.; Mengoni, A.; Wallner, A.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Álvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Barbagallo, M.; Baumann, P.; Bečvář, F.; Belloni, F.; Berthoumieux, E.; Calviani, M.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Carrillo de Albornoz, A.; Cennini, P.; Chepel, V.; Chiaveri, E.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Dolfini, R.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fitzpatrick, L.; Frais-Koelbl, H.; Fujii, K.; Furman, W.; Goncalves, I.; González-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Isaev, S.; Jericha, E.; Kadi, Y.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Ketlerov, V.; Koehler, P.; Konovalov, V.; Kossionides, E.; Krtička, M.; Lampoudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Losito, R.; Lozano, M.; Lukic, S.; Marganiec, J.; Marques, L.; Marrone, S.; Martínez, T.; Mastinu, P.; Mendoza, E.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Oshima, M.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Pigni, M. T.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Sarmento, R.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tarrío, D.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wendler, H.; Wiescher, M.; Wisshak, K.

    2011-03-01

    The cross section of the reaction Au197(n,γ) was measured with the time-of-flight technique at the n_TOF (neutron time-of-flight) facility in the unresolved resonance region between 5 and 400 keV using a pair of C6D6 (where D denotes H2) liquid scintillators for the detection of prompt capture γ rays. The results with a total uncertainty of 3.9%-6.7% for a resolution of 20 bins per energy decade show fair agreement with the Evaluated Nuclear Data File Version B-VII.0 (ENDF/B-VII.0), which contains the standard evaluation. The Maxwellian-averaged cross section (MACS) at 30 keV is in excellent agreement with the one according to the ENDF/B-VII.0 evaluation and 4.7% higher than the MACS measured independently by activation technique. Structures in the cross section, which had also been reported earlier, have been interpreted as being due to clusters of resonances.

  11. Revisiting the region of the open cluster NGC 5606

    NASA Astrophysics Data System (ADS)

    Orsatti, A. M.; Feinstein, C.; Vega, E. I.; Vergne, M. M.

    2007-08-01

    We present polarimetric observations in the UBVRI bands corresponding to 54 stars located in the direction of NGC 5606. Our intention is to analyze the dust characteristics between the Sun and the cluster, as well as to confirm doubtful memberships using polarimetric tools. We also want to determine if a group of 11 B and A stars identified in the past by Vázquez & Feinstein (1991, A&AS, 87, 383) in front of NGC 5606 has any physical entity. From polarimetric data we have found at least two dust layers along the line of sight to the open cluster. The observations show that both dust layers have their local magnetic field with an orientation which is close to the direction of the Galactic Plane (θ = 70.0 °), but the direction of the polarimetric vector for the members of the cluster seems to be lower than this value. NGC 5606 can be polarimetrically characterized with P_max = 2.97% and θv = 63.5 °. The internal dispersion of the polarization values for the members of NGC 5606 seems to be compatible with intracluster dust. We were able to add four possible new members to the list of stars in NGC 5606, and to reject others accepted as members in past investigations; and we identified 17 (out of the 54 observed stars) with intrinsic polarization in their light. The group of late B- and A-type stars could be physically related, with characteristics of an open cluster of intermediate age (between 0.79 and 1. × 108 yr). For this group we obtained representative values of P = 2.12% and θv = 70.0 °. The new cluster, which we have provisionally named Anon (La Plata 1), extends from NE to SW across the face of NGC 5606 covering about 10'. The fitting procedure of Schmidt-Kaler's ZAMS (1982, in Landolt/Bornstein, Neue Series VI/2b) was used to derive the distance to the group, obtaining a distance modulus of Vo - Mv = 9.90 (649 pc from the Sun). The mean color excess associated with the small group is EB-V = 0.27 ± 0.08 mag and the dust distribution shows great

  12. Advantages and Limitations of Cluster Analysis in Interpreting Regional GPS Velocity Fields in California and Elsewhere

    NASA Astrophysics Data System (ADS)

    Thatcher, W. R.; Savage, J. C.; Simpson, R.

    2012-12-01

    Regional Global Positioning System (GPS) velocity observations are providing increasingly precise mappings of actively deforming continental lithosphere. Cluster analysis, a venerable data analysis method, offers a simple, visual exploratory tool for the initial organization and investigation of GPS velocities (Simpson et al., 2012 GRL). Here we describe the application of cluster analysis to GPS velocities from three regions, the Mojave Desert and the San Francisco Bay regions in California, and the Aegean in the eastern Mediterranean. Our goal is to illustrate the strengths and shortcomings of the method in searching for spatially coherent patterns of deformation, including evidence for and against block-like behavior in these 3 regions. The deformation fields from dense regional GPS networks can often be concisely described in terms of relatively coherent blocks bounded by active faults, although the choice of blocks, their number and size, is subjective and usually guided by the distribution of known faults. Cluster analysis applied to GPS velocities provides a completely objective method for identifying groups of observations ranging in size from 10s to 100s of km in characteristic dimension based solely on the similarities of their velocity vectors. In the three regions we have studied, statistically significant clusters are almost invariably spatially coherent, fault bounded, and coincide with elastic, geologically identified structural blocks. Often, higher order clusters that are not statistically significant are also spatially coherent, suggesting the existence of additional blocks, or defining regions of other tectonic importance (e.g. zones of localized elastic strain accumulation near locked faults). These results can be used to both formulate tentative tectonic models with testable consequences and to suggest focused new measurements in under-sampled regions. Cluster analysis applied to GPS velocities has several potential limitations, aside from the

  13. Study of Seismic Clusters at Bahía de Banderas Region, Mexico

    NASA Astrophysics Data System (ADS)

    Nunez-Cornu, F. J.; Rutz-Lopez, M.; Suarez-Plascencia, C.; Trejo-Gomez, E.

    2010-12-01

    Given that the coast in the states of Jalisco and south of the state of Nayarit is located within a region of high seismic potential and also because population is increasing, perhaps motivated by the development of tourism, the Civil Defense authorities of Jalisco and the Centro de Sismología y Volcanología de Occidente-SisVOc of Universidad de Guadalajara started in the year 2000 a joint project to study the seismic risk of the region, including the seismic monitoring of Colima volcano (located between the states of Jalisco and Colima). This work focuses on the study of seismicity in the area of Bahía de Banderas and northern coast of Jalisco. To this end, we perform an analysis of available seismograms to characterize active structures, their relationship to surface morphology, and possible reach of these structures into the shallow parts of the bay. The data used in this work are waveforms recorded during the year 2003 during which the seismograph network spanned the region of study. Our method is based on the identification of seismic clusters or families using cross-correlation of waveforms, earthquake relocation and modeling of fault planes. From an initial data set of 404 earthquakes located during 2003, 96 earthquakes could be related to 17 potentially active continental structures. A modeling of fault planes was possible for 11 of these structures. Subgroups of 7 structures are aligned parallel to the Middle America Trench, a possible consequence of oblique subduction. The magnitudes of earthquakes grouped into families is less than 3.6 (Ml), corresponding to fault dimensions of hundreds of meters.

  14. Globular clusters in the inner regions of NGC 5128 (CENTAURUS A)

    SciTech Connect

    Minniti, D. |; Alonso, M.V.; Goudfrooij, P.; Jablonka, P.; Meylan, G.

    1996-08-01

    We have identified 26 new globular cluster candidates in the inner 3 kpc of NGC 5128 (Centaurus A), the nearest known large galaxy that is the probable product of a merger. The clusters are selected on the basis of their structural parameters (observed core diameters and ellipticities), as measured from archival Wide Field Planetary Camera (WFPC) {ital Hubble} {ital Space} {ital Telescope} ({ital HST}) images. IR photometry obtained with IRAC2B at the ESO/MPI 2.2 m telescope is combined with the optical HST photometry. Most of these clusters have normal colors typical of old globular clusters like those found in the Milky Way and M31. We estimate their metal abundances based on the {ital R}{minus}{ital K}{sub 0} color, confirming the existence of a metallicity gradient in the inner regions of NGC 5128. The presence of metal-rich globular clusters suggests that one of the colliding galaxies was a bulge-dominated galaxy ({ital E} or early {ital S}). A few clusters have colors and magnitudes similar to intermediate-age clusters containing carbon stars in the Magellanic Clouds. If the intermediate-age clusters were formed during a merger, then this episode must have occurred a few gigayears ago. Alternatively, we are looking at the cluster members of one of the colliding galaxies, which would then have been a late-type disk galaxy. {copyright} {ital 1996 The American Astronomical Society.}

  15. Sequence breakpoints in the aflatoxin biosynthesis gene cluster and flanking regions in nonaflatoxigenic Aspergillus flavus isolates.

    PubMed

    Chang, Perng-Kuang; Horn, Bruce W; Dorner, Joe W

    2005-11-01

    Aspergillus flavus populations are genetically diverse. Isolates that produce either, neither, or both aflatoxins and cyclopiazonic acid (CPA) are present in the field. We investigated defects in the aflatoxin gene cluster in 38 nonaflatoxigenic A. flavus isolates collected from southern United States. PCR assays using aflatoxin-gene-specific primers grouped these isolates into eight (A-H) deletion patterns. Patterns C, E, G, and H, which contain 40 kb deletions, were examined for their sequence breakpoints. Pattern C has one breakpoint in the cypA 3' untranslated region (UTR) and another in the verA coding region. Pattern E has a breakpoint in the amdA coding region and another in the ver1 5'UTR. Pattern G contains a deletion identical to the one found in pattern C and has another deletion that extends from the cypA coding region to one end of the chromosome as suggested by the presence of telomeric sequence repeats, CCCTAATGTTGA. Pattern H has a deletion of the entire aflatoxin gene cluster from the hexA coding region in the sugar utilization gene cluster to the telomeric region. Thus, deletions in the aflatoxin gene cluster among A. flavus isolates are not rare, and the patterns appear to be diverse. Genetic drift may be a driving force that is responsible for the loss of the entire aflatoxin gene cluster in nonaflatoxigenic A. flavus isolates when aflatoxins have lost their adaptive value in nature.

  16. Clustering in Engineering Education in the Baltic Region

    ERIC Educational Resources Information Center

    Ahrens, Andreas; Zascerinska, Jelena

    2011-01-01

    The contemporary situation in the Baltic region, namely, the lack of working places due to the structural problems, a high unemployment rate, the migration of highly qualified people and the low rate of self-employees, demands on innovation as an engine of the economic development with a strong impact on sustainable development in the European…

  17. 75 FR 7464 - Energy Efficient Building Systems Regional Innovation Cluster Initiative-Joint Federal Funding...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-19

    ... interested parties to learn about the Joint Federal Funding Opportunity Announcement (see http:// ] www... (the ``Energy Regional Innovation Cluster'' or ``E-RIC'') and will work to disseminate new technologies... the area, the E-RIC will create an economically dynamic region focused on energy efficient...

  18. A DEEP UBVRI CCD PHOTOMETRY OF SIX OPEN STAR CLUSTERS IN THE GALACTIC ANTICENTER REGION

    SciTech Connect

    Lata, Sneh; Pandey, Anil K.; Kumar, Brijesh; Bhatt, Himali; Pace, Giancarlo; Sharma, Saurabh

    2010-02-15

    We present deep UBVRI CCD photometry of six open star clusters situated in the Galactic anticenter region (l{approx} 120-200 deg.). The sample includes three unstudied (Be 6, Be 77, King 17) and three partly studied open clusters (Be 9, NGC 2186, and NGC 2304). The fundamental parameters have been determined by comparing color-color and color-magnitude diagrams with the theoretical models. The structural parameters and morphology of the clusters were discussed on the basis of radial density profiles and isodensity contours, respectively. The isodensity contours show that all the clusters have asymmetric shapes. An investigation of structural parameters indicates that the evolution of core and corona of the clusters is mainly controlled by internal relaxation processes.

  19. Extragalactic Ultracompact HII Regions: Probing the Birth Environments of Super Star Clusters

    NASA Astrophysics Data System (ADS)

    Johnson, K. E.

    2004-12-01

    In recent years, a number of extragalactic massive star clusters that are still deeply embedded in their birth material have been discovered. These objects represent the youngest stage of massive star cluster evolution yet observed, and the most massive and dense of these may be proto globular clusters. Their properties appear to be similar to those of ultracompact HII regions in the Galaxy, but scaled up in total mass and luminosity. In many cases, these clusters are only visible at mid-IR to radio wavelengths, and they have typically been detected as ``inverted'' spectrum radio sources. However, the set of existing observations is anemic, and our current physical model for these natal clusters in simplistic. This article will overview what we think we know about these objects based on existing observations and outline some of the most significant gaps in our current understanding.

  20. Comparison of calculated cross sections for secondary electron emission from a water molecule and clusters of water molecules by protons

    SciTech Connect

    Long, K.A.; Paretzke, H.G. )

    1991-07-15

    Double-differential cross sections for the emission of secondary electrons, as a function of emission angle and energy, from a water molecule, a cluster of water molecules, and liquid water due to proton impact have been calculated using the dielectric response function of the target material and a method which uses an integral formulation of the density-functional theory. From these double-differential cross sections, single-differential and total cross sections, and the energy loss per unit path length, have been calculated by successive integration. The results have been compared to available experimental results and, in the case of single-differential cross sections, also to empirical models. A comparison has been made between the results for the molecule and the central molecule of the cluster in order to obtain insight into how the cross sections might change in the condensed phase, namely in liquid water.

  1. Long regional magnetotelluric profile crossing geotectonic structures of central Poland

    NASA Astrophysics Data System (ADS)

    Stefaniuk, M.; Pokorski, J.; Wojdyla, M.

    2009-04-01

    Introduction The magnetotelluric survey was made along a regional profile, which runs across Poland from south-west to north-east during 2005-2006 years. The profile crosses major geological structures of Central Poland, including the Variscan Externides and Variscan foredeep, the Transeuropean Suture Zone and the marginal zone of East European Craton. The main objectives of the project include identification of sub-Zechstein sedimentary structures and evaluation of resistivity distribution within the deep crust, especially at the contact of East European Precambrian Craton and Central Europe Paleozoic structures. The length of the profile is about 700 km; 161 deep magnetotelluric sounding sites were made with a medium spacing of about 4 km. Data acquisition and processing The recording of the components of natural electromagnetic field was made with a broad range of frequencies, varying from 0.0003 Hz up to 575 Hz with use of MT-1 system of Electromagnetic Instruments Incorporation. This frequency band allowed obtaining the information about geology ranging from a few dozen meters to approximately 100 km, depending on the vertical distribution of the resistivity inside geological medium. To reduce the electromagnetic noise, magnetic and electric remote reference was applied. A remote reference site was located at a distance of over 100 km of field sites. Processing of the recorded data included the estimation of the components of impedance tensor (Zxx, Zxy, Zyx and Zyy ), with use of robust type procedures. The components of the impedance tensor allowed in a subsequent step for calculation of field curves for two orientations of the measurement system (XY - described further as the TM mode and YX - TE mode) and additional parameters of the medium like skew, strike, pole diagrams etc. Recording of the vertical component of electromagnetic field (Hz) allowed calculation of tipper parameter T. Magnetotelluric soundings interpretation Geophysical interpretation of MT

  2. Manual hierarchical clustering of regional geochemical data using a Bayesian finite mixture model

    USGS Publications Warehouse

    Ellefsen, Karl J.; Smith, David

    2016-01-01

    Interpretation of regional scale, multivariate geochemical data is aided by a statistical technique called “clustering.” We investigate a particular clustering procedure by applying it to geochemical data collected in the State of Colorado, United States of America. The clustering procedure partitions the field samples for the entire survey area into two clusters. The field samples in each cluster are partitioned again to create two subclusters, and so on. This manual procedure generates a hierarchy of clusters, and the different levels of the hierarchy show geochemical and geological processes occurring at different spatial scales. Although there are many different clustering methods, we use Bayesian finite mixture modeling with two probability distributions, which yields two clusters. The model parameters are estimated with Hamiltonian Monte Carlo sampling of the posterior probability density function, which usually has multiple modes. Each mode has its own set of model parameters; each set is checked to ensure that it is consistent both with the data and with independent geologic knowledge. The set of model parameters that is most consistent with the independent geologic knowledge is selected for detailed interpretation and partitioning of the field samples.

  3. Cross-correlation Weak Lensing of SDSS galaxy Clusters II: Cluster Density Profiles and the Mass--Richness Relation

    SciTech Connect

    Johnston, David E.; Sheldon, Erin S.; Wechsler, Risa H.; Rozo, Eduardo; Koester, Benjamin P.; Frieman, Joshua A.; McKay, Timothy A.; Evrard, August E.; Becker, Matthew R.; Annis, James

    2007-09-28

    We interpret and model the statistical weak lensing measurements around 130,000 groups and clusters of galaxies in the Sloan Digital Sky Survey presented by Sheldon et al. (2007). We present non-parametric inversions of the 2D shear profiles to the mean 3D cluster density and mass profiles in bins of both optical richness and cluster i-band luminosity. Since the mean cluster density profile is proportional to the cluster-mass correlation function, the mean profile is spherically symmetric by the assumptions of large-scale homogeneity and isotropy. We correct the inferred 3D profiles for systematic effects, including non-linear shear and the fact that cluster halos are not all precisely centered on their brightest galaxies. We also model the measured cluster shear profile as a sum of contributions from the brightest central galaxy, the cluster dark matter halo, and neighboring halos. We infer the relations between mean cluster virial mass and optical richness and luminosity over two orders of magnitude in cluster mass; the virial mass at fixed richness or luminosity is determined with a precision of {approx} 13% including both statistical and systematic errors. We also constrain the halo concentration parameter and halo bias as a function of cluster mass; both are in good agreement with predictions from N-body simulations of LCDM models. The methods employed here will be applicable to deeper, wide-area optical surveys that aim to constrain the nature of the dark energy, such as the Dark Energy Survey, the Large Synoptic Survey Telescope and space-based surveys.

  4. Functional analysis of the upstream regulatory region of chicken miR-17-92 cluster.

    PubMed

    Min, Cheng; Wenjian, Zhang; Tianyu, Xing; Xiaohong, Yan; Yumao, Li; Hui, Li; Ning, Wang

    2016-08-01

    miR-17-92 cluster plays important roles in cell proliferation, differentiation, apoptosis, animal development and tumorigenesis. The transcriptional regulation of miR-17-92 cluster has been extensively studied in mammals, but not in birds. To date, avian miR-17-92 cluster genomic structure has not been fully determined. The promoter location and sequence of miR-17-92 cluster have not been determined, due to the existence of a genomic gap sequence upstream of miR-17-92 cluster in all the birds whose genomes have been sequenced. In this study, genome walking was used to close the genomic gap upstream of chicken miR-17-92 cluster. In addition, bioinformatics analysis, reporter gene assay and truncation mutagenesis were used to investigate functional role of the genomic gap sequence. Genome walking analysis showed that the gap region was 1704 bp long, and its GC content was 80.11%. Bioinformatics analysis showed that in the gap region, there was a 200 bp conserved sequence among the tested 10 species (Gallus gallus, Homo sapiens, Pan troglodytes, Bos taurus, Sus scrofa, Rattus norvegicus, Mus musculus, Possum, Danio rerio, Rana nigromaculata), which is core promoter region of mammalian miR-17-92 host gene (MIR17HG). Promoter luciferase reporter gene vector of the gap region was constructed and reporter assay was performed. The result showed that the promoter activity of pGL3-cMIR17HG (-4228/-2506) was 417 times than that of negative control (empty pGL3 basic vector), suggesting that chicken miR-17-92 cluster promoter exists in the gap region. To further gain insight into the promoter structure, two different truncations for the cloned gap sequence were generated by PCR. One had a truncation of 448 bp at the 5'-end and the other had a truncation of 894 bp at the 3'-end. Further reporter analysis showed that compared with the promoter activity of pGL3-cMIR17HG (-4228/-2506), the reporter activities of the 5'-end truncation and the 3'-end truncation were reduced by 19

  5. A statistical study of the cross-shock electric potential at low Mach number, quasi-perpendicular bow shock crossings using Cluster data

    NASA Astrophysics Data System (ADS)

    Dimmock, A. P.; Balikhin, M. A.; Krasnoselskikh, V. V.; Walker, S. N.; Bale, S. D.; Hobara, Y.

    2012-02-01

    The cross-shock electrostatic potential at the front of collision-less shocks plays a key role in the distribution of energy at the shock front. Multipoint measurements such as those provided by the Cluster II mission provide an ideal framework for the study of the cross-shock potential because of their ability to distinguish between temporal and spacial variations at the shock front. We present a statistical study of the cross-shock potential calculated for around 50 crossings of the terrestrial bow shock. The statistical dependency of the normalized (with resect to upstream ion kinetic energy) cross-shock potential (ΦK) on the upstream Alfvén Mach number is in good agreement with analytical results that predict decrease of Φk with increasing Mach number.

  6. Magnetic self-assembly of microparticle clusters in an aqueous two-phase microfluidic cross-flow

    NASA Astrophysics Data System (ADS)

    Abbasi, Niki; Jones, Steven G.; Moon, Byeong-Ui; Tsai, Scott S. H.

    2015-11-01

    We present a technique that self-assembles paramagnetic microparticles on the interface of aqueous two-phase system (ATPS) fluids in a microfluidic cross-flow. A co-flow of the ATPS is formed in the microfluidic cross channel as the flows of a dilute dextran (DEX) phase, along with a flow-focused particle suspension, converges with a dilute polyethylene glycol (PEG) phase. The microparticles arrive at the liquid-liquid interface and self-assemble into particle clusters due to forces on the particles from an applied external magnetic field gradient, and the interfacial tension of the ATPS. The microparticles form clusters at the interface, and once the cluster size grows to a critical value, the cluster passes through the interface. We control the size of the self-assembled clusters, as they pass through the interface, by varying the strength of the applied magnetic field gradient and the ATPS interfacial tension. We observe rich assembly dynamics, from the formation of Pickering emulsions to clusters that are completely encapsulated inside DEX phase droplets. We anticipate that this microparticle self-assembly method may have important biotechnological applications that require the controlled assembly of cells into clusters.

  7. A modified procedure for mixture-model clustering of regional geochemical data

    USGS Publications Warehouse

    Ellefsen, Karl J.; Smith, David B.; Horton, John D.

    2014-01-01

    A modified procedure is proposed for mixture-model clustering of regional-scale geochemical data. The key modification is the robust principal component transformation of the isometric log-ratio transforms of the element concentrations. This principal component transformation and the associated dimension reduction are applied before the data are clustered. The principal advantage of this modification is that it significantly improves the stability of the clustering. The principal disadvantage is that it requires subjective selection of the number of clusters and the number of principal components. To evaluate the efficacy of this modified procedure, it is applied to soil geochemical data that comprise 959 samples from the state of Colorado (USA) for which the concentrations of 44 elements are measured. The distributions of element concentrations that are derived from the mixture model and from the field samples are similar, indicating that the mixture model is a suitable representation of the transformed geochemical data. Each cluster and the associated distributions of the element concentrations are related to specific geologic and anthropogenic features. In this way, mixture model clustering facilitates interpretation of the regional geochemical data.

  8. INTER- AND INTRA-CLUSTER AGE GRADIENTS IN MASSIVE STAR FORMING REGIONS AND INDIVIDUAL NEARBY STELLAR CLUSTERS REVEALED BY MYStIX

    NASA Astrophysics Data System (ADS)

    Getman, Konstantin V.; Feigelson, Eric; Kuhn, Michael A.; Broos, Patrick S; Townsley, Leisa K.; Naylor, Tim; Povich, Matthew S.; Luhman, Kevin; Garmire, Gordon

    2014-08-01

    The MYStIX (Massive Young Star-Forming Complex Study in Infrared and X-ray) project seeks to characterize 20 OB-dominated young star forming regions (SFRs) at distances <4 kpc using photometric catalogs from the Chandra X-ray Observatory, Spitzer Space Telescope, UKIRT and 2MASS surveys. As part of the MYStIX project, we developed a new stellar chronometer that employs near-infrared and X-ray photometry data, AgeJX. Computing AgeJX averaged over MYStIX (sub)clusters reveals previously unknown age gradients across most of the MYStIX regions as well as within some individual rich clusters. Within the SFRs, the inferred AgeJX ages are youngest in obscured locations in molecular clouds, intermediate in revealed stellar clusters, and oldest in distributed stellar populations. Noticeable intra-cluster gradients are seen in the NGC 2024 (Flame Nebula) star cluster and the Orion Nebula Cluster (ONC): stars in cluster cores appear younger and thus were formed later than stars in cluster halos. The latter result has two important implications for the formation of young stellar clusters. Clusters likely form slowly: they do not arise from a single nearly-instantaneous burst of star formation. The simple models where clusters form inside-out are likely incorrect, and more complex models are needed. We provide several star formation scenarios that alone or in combination may lead to the observed core-halo age gradients.

  9. On the formation mechanisms of kinetic Alfven waves in the mid-altitude cusp region: Cluster observations

    NASA Astrophysics Data System (ADS)

    Duan, S. P.; Liu, Z. X.; Cao, J. B.; Reme, H.; Balogh, A.; Fazakerley, A. N.

    According to the observation data by the Cluster spacecraft encountering the mid-altitude cusp region and the theory research work of the formation mechanism of kinetic Alfven waves it can be concluded that kinetic Alfven waves can be come into being in the mid-altitude polar cusp Using the observation data detected by the Cluster CIS FGM and PEACE crossing through the mid-altitude cusp region on 4 July 2001 we find that ion and electron number densities are obviously disturbed and protons are always in the down-going direction We obtain that the values of plasma beta are in the range between 0 002 and 0 01 from 13 24 00 to 13 39 00 They are larger than the mass ratio value of electron and proton That implies the mid-altitude polar cusp is a kinetic region Ion and electron density inhomogeneity and the ion beam with down-going direction are the main factors for the formation of kinetic Alfven waves The observational results are consonant with the results obtained from the theory research that the plasma density inhomogeneity and ions motion play important roles in the formation process of kinetic Alfven waves The observational properties of kinetic Alfven waves will be investigated in our following research work

  10. X-ray survey of galaxy clusters in the SDSS Stripe 82 region

    NASA Astrophysics Data System (ADS)

    Durret, Florence; Takey, Ali

    2016-07-01

    We conducted a survey of galaxy clusters detected from XMM-Newton observations covering an area of 11.25 deg^2 in the Stripe 82 region of the Sloan Digital Sky Survey (SDSS). We found 94 X-ray cluster candidates from the third XMM-Newton serendipitous source catalogue (3XMM-DR5) and correlated this list with recently published X-ray and optically selected cluster catalogues to obtain optical confirmations and redshifts (between 0.05 and 1.19, with a median of 0.36) for 54 galaxy groups/clusters. Of these, 17 are newly X-ray discovered clusters and 45 systems with spectroscopic confirmations. Among the remaining candidates, 25 sources are distant cluster candidates (beyond a redshift of 0.6). We will present preliminary results on the X-ray and optical properties of these clusters: luminosities and temperatures of the X-ray gas, and optical properties of the galaxies (morphology, luminosity functions).

  11. Photometry and spectroscopy of stars in the region of a highly reddened cluster in ARA

    NASA Astrophysics Data System (ADS)

    Westerlund, B. E.

    1987-09-01

    VRI photographic photometry is presented for 258 stars in the region of the cluster Wd1 in Ara together with near-infrared spectrophotometry of the brightest stars. The brightest member stars of the cluster are shown to be of spectral types B2 Ia to M2 Ia, forming a well defined sequence of supergiants with the maximum visual luminosity being reached in classes A2 and G0. One of the stars is of type Be with an extremely extended shell. Weak hydrogen emission can be traced in the spectra of a number of the stars as well as in between the stars. The interstellar absorption is very heavy, reaching A(V) = 10 mag; the surrounding field has an average absorption of about 3 mag. A redetermination of the distance of the cluster leads to a value of about 5 kpc as most likely. The age of the cluster is estimated to about seven million years.

  12. Dynamical Evolution of Globular Clusters Moving within the Galactic Central Regions

    NASA Astrophysics Data System (ADS)

    Miocchi, P.; Capuzzo-Dolcetta, R.

    The decaying of globular clusters towards galactic nuclei can be an efficient dynamical mechanism to concentrate high amounts of stellar matter in the very inner galactic regions, so to contribute significantly to the accretion and feeding of a central massive black hole. Such decaying is made possible by the dynamical friction which dissipates the cluster orbital kinetic energy in a reasonably short time. Quantitative indications that this mechanism is capable to sustain the observed AGN luminosities have been already given. However, there is need of a more refined numerical approach. In particular, while in normal conditions dynamical friction is well understood and its effects sufficiently well described, it is not clear what happens when a cluster decays into a region which ``encloses'' a bulge mass comparable with that of the cluster itself. In this case the gravitational feed-back of the cluster on the bulge is very important and cannot be neglected. Moreover, it is quite difficult to predict, by just analytical means, the tidal effects due to the presence of the massive black hole on clusters' dynamics. We want to show the results obtained by our simulations in this context. The simulations have been performed both with a serial and a parallel `tree-code' (on a CRAY T3E), using a leap-frog scheme for the integration of particles' trajectories, with individual and variable time steps. A completely self-consistent particle representation has been used, not only for the globular cluster but also for the nuclear region of the bulge and for the massive black hole.

  13. Recursive Hierarchical Image Segmentation by Region Growing and Constrained Spectral Clustering

    NASA Technical Reports Server (NTRS)

    Tilton, James C.

    2002-01-01

    This paper describes an algorithm for hierarchical image segmentation (referred to as HSEG) and its recursive formulation (referred to as RHSEG). The HSEG algorithm is a hybrid of region growing and constrained spectral clustering that produces a hierarchical set of image segmentations based on detected convergence points. In the main, HSEG employs the hierarchical stepwise optimization (HS WO) approach to region growing, which seeks to produce segmentations that are more optimized than those produced by more classic approaches to region growing. In addition, HSEG optionally interjects between HSWO region growing iterations merges between spatially non-adjacent regions (i.e., spectrally based merging or clustering) constrained by a threshold derived from the previous HSWO region growing iteration. While the addition of constrained spectral clustering improves the segmentation results, especially for larger images, it also significantly increases HSEG's computational requirements. To counteract this, a computationally efficient recursive, divide-and-conquer, implementation of HSEG (RHSEG) has been devised and is described herein. Included in this description is special code that is required to avoid processing artifacts caused by RHSEG s recursive subdivision of the image data. Implementations for single processor and for multiple processor computer systems are described. Results with Landsat TM data are included comparing HSEG with classic region growing. Finally, an application to image information mining and knowledge discovery is discussed.

  14. FIESTA 3: Cluster-parallelizable multiloop numerical calculations in physical regions

    NASA Astrophysics Data System (ADS)

    Smirnov, A. V.

    2014-07-01

    The goal of this paper is to present a new major release of the program FIESTA (Feynman Integral Evaluation by a Sector decomposiTion Approach). This version presents features like cluster-parallelization, new asymptotic expansion algorithms, calculations in physical regions, new sector-decomposition strategies, as well as multiple speed, memory, and stability improvements.

  15. The W40 region in the gould belt: An embedded cluster and H II region at the junction of filaments

    SciTech Connect

    Mallick, K. K.; Ojha, D. K.; Kumar, M. S. N.; Samal, M. R.; Pirogov, L.

    2013-12-20

    We present a multiwavelength study of the W40 star-forming region using infrared (IR) observations in the UKIRT JHK bands, Spitzer Infrared Array Camera bands, and Herschel PACS bands, 2.12 μm H{sub 2} narrowband imaging, and radio continuum observations from GMRT (610 and 1280 MHz), in a field of view (FoV) of ∼34' × 40'. Archival Spitzer observations in conjunction with near-IR observations are used to identify 1162 Class II/III and 40 Class I sources in the FoV. The nearest-neighbor stellar surface density analysis shows that the majority of these young stellar objects (YSOs) constitute the embedded cluster centered on the high-mass source IRS 1A South. Some YSOs, predominantly the younger population, are distributed along and trace the filamentary structures at lower stellar surface density. The cluster radius is measured to be 0.44 pc—matching well with the extent of radio emission—with a peak density of 650 pc{sup –2}. The JHK data are used to map the extinction in the region, which is subsequently used to compute the cloud mass—126 M {sub ☉} and 71 M {sub ☉} for the central cluster and the northern IRS 5 region, respectively. H{sub 2} narrowband imaging shows significant emission, which prominently resembles fluorescent emission arising at the borders of dense regions. Radio continuum analysis shows that this region has a blister morphology, with the radio peak coinciding with a protostellar source. Free-free emission spectral energy distribution analysis is used to obtain physical parameters of the overall photoionized region and the IRS 5 sub-region. This multiwavelength scenario is suggestive of star formation having resulted from the merging of multiple filaments to form a hub. Star formation seems to have taken place in two successive epochs, with the first epoch traced by the central cluster and the high-mass star(s)—followed by a second epoch that is spreading into the filaments as uncovered by the Class I sources and even younger

  16. Galaxy populations in the infall regions of z ˜ 0.25 clusters

    NASA Astrophysics Data System (ADS)

    Verdugo, M.; Ziegler, B. L.

    2006-06-01

    We investigate 6 clusters of galaxies at intermediate redshift ( 0.18 < z < 0.3), in particular the star formation activity of galaxies. Our Calar Alto MOSCA spectra cover large fields of view reaching out to 2-4 virial radii. This outer region is often called the infall region since here newly arriving galaxies from the surrounding field encounter the special environment of clusters for the first time. We selected 3 fields containing 2 clusters each from the X-ray Dark Cluster Survey (XDC, Gilbank et al. 2004 MNRAS, 348, 551, G04) Each 40'×40' field was observed with 7-8 slit-masks yielding 553 low-resolution galaxy spectra (R ˜ 500). The results for the first field (R285), were already published by Gerken et al. (2004, A&A, 421, 59). We select [OII]λ3717 and Hα equivalent widths as indicators of star formation activity. In the analysis, we ``averaged'' 4 clusters: VMF73 (z=0.254) and VMF74 (z=0.18) in XDCS field R285 and VMF131 (z=0.295) and VMF132 (z=0.246) in field R265 and we found an increase of the star forming activity towards larger cluster-centric distances as well as towards shallower projected galaxy densities. Galaxies in the third field R220 exhibit a complex redshift structure which makes membership determination difficulty and were excluded of the overall analysis. However, we clearly identified the cluster VMF194 (z=0.211) and confirm another cluster at z=0.261 detected by G04. In addition, a group of galaxies with similar coordinates to VMF194 at z=0.243 is significant. We also detected a population of red star-forming galaxies, belonging to the red-sequence of the clusters and even redder. Those galaxies show a moderate star-forming activity and do not show any other spectral peculiarities. We do not detect any post-starburst galaxy nor AGN in our cluster sample.

  17. Molecular characterization of the PR-toxin gene cluster in Penicillium roqueforti and Penicillium chrysogenum: cross talk of secondary metabolite pathways.

    PubMed

    Hidalgo, Pedro I; Ullán, Ricardo V; Albillos, Silvia M; Montero, Olimpio; Fernández-Bodega, María Ángeles; García-Estrada, Carlos; Fernández-Aguado, Marta; Martín, Juan-Francisco

    2014-01-01

    The PR-toxin is a potent mycotoxin produced by Penicillium roqueforti in moulded grains and grass silages and may contaminate blue-veined cheese. The PR-toxin derives from the 15 carbon atoms sesquiterpene aristolochene formed by the aristolochene synthase (encoded by ari1). We have cloned and sequenced a four gene cluster that includes the ari1 gene from P. roqueforti. Gene silencing of each of the four genes (named prx1 to prx4) resulted in a reduction of 65-75% in the production of PR-toxin indicating that the four genes encode enzymes involved in PR-toxin biosynthesis. Interestingly the four silenced mutants overproduce large amounts of mycophenolic acid, an antitumor compound formed by an unrelated pathway suggesting a cross-talk of PR-toxin and mycophenolic acid production. An eleven gene cluster that includes the above mentioned four prx genes and a 14-TMS drug/H(+) antiporter was found in the genome of Penicillium chrysogenum. This eleven gene cluster has been reported to be very poorly expressed in a transcriptomic study of P. chrysogenum genes under conditions of penicillin production (strongly aerated cultures). We found that this apparently silent gene cluster is able to produce PR-toxin in P. chrysogenum under static culture conditions on hydrated rice medium. Noteworthily, the production of PR-toxin was 2.6-fold higher in P. chrysogenum npe10, a strain deleted in the 56.8kb amplifiable region containing the pen gene cluster, than in the parental strain Wisconsin 54-1255 providing another example of cross-talk between secondary metabolite pathways in this fungus. A detailed PR-toxin biosynthesis pathway is proposed based on all available evidence.

  18. Hierarchical Regional Disparities and Potential Sector Identification Using Modified Agglomerative Clustering

    NASA Astrophysics Data System (ADS)

    Munandar, T. A.; Azhari; Mushdholifah, A.; Arsyad, L.

    2017-03-01

    Disparities in regional development methods are commonly identified using the Klassen Typology and Location Quotient. Both methods typically use the data on the gross regional domestic product (GRDP) sectors of a particular region. The Klassen approach can identify regional disparities by classifying the GRDP sector data into four classes, namely Quadrants I, II, III, and IV. Each quadrant indicates a certain level of regional disparities based on the GRDP sector value of the said region. Meanwhile, the Location Quotient (LQ) is usually used to identify potential sectors in a particular region so as to determine which sectors are potential and which ones are not potential. LQ classifies each sector into three classes namely, the basic sector, the non-basic sector with a competitive advantage, and the non-basic sector which can only meet its own necessities. Both Klassen Typology and LQ are unable to visualize the relationship of achievements in the development clearly of each region and sector. This research aimed to develop a new approach to the identification of disparities in regional development in the form of hierarchical clustering. The method of Hierarchical Agglomerative Clustering (HAC) was employed as the basis of the hierarchical clustering model for identifying disparities in regional development. Modifications were made to HAC using the Klassen Typology and LQ. Then, HAC which had been modified using the Klassen Typology was called MHACK while HAC which had been modified using LQ was called MACLoQ. Both algorithms can be used to identify regional disparities (MHACK) and potential sectors (MACLoQ), respectively, in the form of hierarchical clusters. Based on the MHACK in 31 regencies in Central Java Province, it is identified that 3 regencies (Demak, Jepara, and Magelang City) fall into the category of developed and rapidly-growing regions, while the other 28 regencies fall into the category of developed but depressed regions. Results of the MACLo

  19. DISCOVERY OF A POSSIBLY SINGLE BLUE SUPERGIANT STAR IN THE INTRA-CLUSTER REGION OF VIRGO CLUSTER OF GALAXIES

    SciTech Connect

    Ohyama, Youichi; Hota, Ananda

    2013-04-20

    IC 3418 is a dwarf irregular galaxy falling into the Virgo cluster, and a 17 kpc long trail is seen behind the galaxy, which is considered to have formed due to ram pressure stripping. The trail contains compact knots and diffuse blobs of ultraviolet and blue optical emission and, thus, it is a clear site of recent star formation but in an unusual environment, surrounded by a million degree intra-cluster medium. We report on our optical spectroscopy of a compact source in the trail, SDSS J122952.66+112227.8, and show that the optical spectrum is dominated by emission from a massive blue supergiant star. If confirmed, our report would mark the farthest star with spectroscopic observation. We interpret that a massive O-type star formed in situ in the trail has evolved recently out of the main sequence into this blue supergiant phase, and now lacks any detectable spectral sign of its associated H II region. We argue that turbulence within the ram pressure striped gaseous trail may play a dominant role for the star formation within such trails.

  20. Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling

    PubMed Central

    Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

    2015-01-01

    This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols. PMID:26393608

  1. Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

    PubMed

    Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

    2015-09-18

    This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.

  2. THE SLOAN DIGITAL SKY SURVEY CO-ADD: CROSS-CORRELATION WEAK LENSING AND TOMOGRAPHY OF GALAXY CLUSTERS

    SciTech Connect

    Simet, Melanie; Dodelson, Scott; Kubo, Jeffrey M.; Annis, James T.; Hao Jiangang; Johnston, David; Lin, Huan; Soares-Santos, Marcelle; Reis, Ribamar R. R.; Seo, Hee-Jong

    2012-04-01

    The shapes of distant galaxies are sheared by intervening galaxy clusters. We examine this effect in Stripe 82, a 275 deg{sup 2} region observed multiple times in the Sloan Digital Sky Survey (SDSS) and co-added to achieve greater depth. We obtain a mass-richness calibration that is similar to other SDSS analyses, demonstrating that the co-addition process did not adversely affect the lensing signal. We also propose a new parameterization of the effect of tomography on the cluster lensing signal which does not require binning in redshift, and we show that using this parameterization we can detect tomography for stacked clusters at varying redshifts. Finally, due to the sensitivity of the tomographic detection to accurately marginalize over the effect of the cluster mass, we show that tomography at low redshift (where dependence on exact cosmological models is weak) can be used to constrain mass profiles in clusters.

  3. Cross ranking of cities and regions: population versus income

    NASA Astrophysics Data System (ADS)

    Cerqueti, Roy; Ausloos, Marcel

    2015-07-01

    This paper explores the relationship between the inner economical structure of communities and their population distribution through a rank-rank analysis of official data, along statistical physics ideas within two techniques. The data is taken on Italian cities. The analysis is performed both at a global (national) and at a more local (regional) level in order to distinguish ‘macro’ and ‘micro’ aspects. First, the rank-size rule is found not to be a standard power law, as in many other studies, but a doubly decreasing power law. Next, the Kendall τ and the Spearman ρ rank correlation coefficients which measure pair concordance and the correlation between fluctuations in two rankings, respectively,—as a correlation function does in thermodynamics, are calculated for finding rank correlation (if any) between demography and wealth. Results show non only global disparities for the whole (country) set, but also (regional) disparities, when comparing the number of cities in regions, the number of inhabitants in cities and that in regions, as well as when comparing the aggregated tax income of the cities and that of regions. Different outliers are pointed out and justified. Interestingly, two classes of cities in the country and two classes of regions in the country are found. ‘Common sense’ social, political, and economic considerations sustain the findings. More importantly, the methods show that they allow to distinguish communities, very clearly, when specific criteria are numerically sound. A specific modeling for the findings is presented, i.e. for the doubly decreasing power law and the two phase system, based on statistics theory, e.g. urn filling. The model ideas can be expected to hold when similar rank relationship features are observed in fields. It is emphasized that the analysis makes more sense than one through a Pearson Π value-value correlation analysis

  4. Regions of micro-calcifications clusters detection based on new features from imbalance data in mammograms

    NASA Astrophysics Data System (ADS)

    Wang, Keju; Dong, Min; Yang, Zhen; Guo, Yanan; Ma, Yide

    2017-02-01

    Breast cancer is the most common cancer among women. Micro-calcification cluster on X-ray mammogram is one of the most important abnormalities, and it is effective for early cancer detection. Surrounding Region Dependence Method (SRDM), a statistical texture analysis method is applied for detecting Regions of Interest (ROIs) containing microcalcifications. Inspired by the SRDM, we present a method that extract gray and other features which are effective to predict the positive and negative regions of micro-calcifications clusters in mammogram. By constructing a set of artificial images only containing micro-calcifications, we locate the suspicious pixels of calcifications of a SRDM matrix in original image map. Features are extracted based on these pixels for imbalance date and then the repeated random subsampling method and Random Forest (RF) classifier are used for classification. True Positive (TP) rate and False Positive (FP) can reflect how the result will be. The TP rate is 90% and FP rate is 88.8% when the threshold q is 10. We draw the Receiver Operating Characteristic (ROC) curve and the Area Under the ROC Curve (AUC) value reaches 0.9224. The experiment indicates that our method is effective. A novel regions of micro-calcifications clusters detection method is developed, which is based on new features for imbalance data in mammography, and it can be considered to help improving the accuracy of computer aided diagnosis breast cancer.

  5. Characterization of Staphylococcus and Corynebacterium Clusters in the Human Axillary Region

    PubMed Central

    Callewaert, Chris; Kerckhof, Frederiek-Maarten; Granitsiotis, Michael S.; Van Gele, Mireille; Van de Wiele, Tom; Boon, Nico

    2013-01-01

    The skin microbial community is regarded as essential for human health and well-being, but likewise plays an important role in the formation of body odor in, for instance, the axillae. Few molecular-based research was done on the axillary microbiome. This study typified the axillary microbiome of a group of 53 healthy subjects. A profound view was obtained of the interpersonal, intrapersonal and temporal diversity of the human axillary microbiota. Denaturing gradient gel electrophoresis (DGGE) and next generation sequencing on 16S rRNA gene region were combined and used as extent to each other. Two important clusters were characterized, where Staphylococcus and Corynebacterium species were the abundant species. Females predominantly clustered within the Staphylococcus cluster (87%, n = 17), whereas males clustered more in the Corynebacterium cluster (39%, n = 36). The axillary microbiota was unique to each individual. Left-right asymmetry occurred in about half of the human population. For the first time, an elaborate study was performed on the dynamics of the axillary microbiome. A relatively stable axillary microbiome was noticed, although a few subjects evolved towards another stable community. The deodorant usage had a proportional linear influence on the species diversity of the axillary microbiome. PMID:23950955

  6. Semi-supervised clustering for parcellating brain regions based on resting state fMRI data

    NASA Astrophysics Data System (ADS)

    Cheng, Hewei; Fan, Yong

    2014-03-01

    Many unsupervised clustering techniques have been adopted for parcellating brain regions of interest into functionally homogeneous subregions based on resting state fMRI data. However, the unsupervised clustering techniques are not able to take advantage of exiting knowledge of the functional neuroanatomy readily available from studies of cytoarchitectonic parcellation or meta-analysis of the literature. In this study, we propose a semi-supervised clustering method for parcellating amygdala into functionally homogeneous subregions based on resting state fMRI data. Particularly, the semi-supervised clustering is implemented under the framework of graph partitioning, and adopts prior information and spatial consistent constraints to obtain a spatially contiguous parcellation result. The graph partitioning problem is solved using an efficient algorithm similar to the well-known weighted kernel k-means algorithm. Our method has been validated for parcellating amygdala into 3 subregions based on resting state fMRI data of 28 subjects. The experiment results have demonstrated that the proposed method is more robust than unsupervised clustering and able to parcellate amygdala into centromedial, laterobasal, and superficial parts with improved functionally homogeneity compared with the cytoarchitectonic parcellation result. The validity of the parcellation results is also supported by distinctive functional and structural connectivity patterns of the subregions and high consistency between coactivation patterns derived from a meta-analysis and functional connectivity patterns of corresponding subregions.

  7. Brazilian Anopheles darlingi Root (Diptera: Culicidae) Clusters by Major Biogeographical Region

    PubMed Central

    Bergo, Eduardo S.; Randel, Melissa A.

    2015-01-01

    The major drivers of the extensive biodiversity of the Neotropics are proposed to be geological and tectonic events together with Pliocene and Pleistocene environmental and climatic change. Geographical barriers represented by the rivers Amazonas/Solimões, the Andes and the coastal mountain ranges in eastern Brazil have been hypothesized to lead to diversification within the primary malaria vector, Anopheles (Nyssorhynchus) darlingi Root, which primarily inhabits rainforest. To test this biogeographical hypothesis, we analyzed 786 single nucleotide polymorphisms (SNPs) in 12 populations of An. darlingi from across the complex Brazilian landscape. Both model-based (STRUCTURE) and non-model-based (Principal Components and Discriminant Analysis) analysis of population structure detected three major genetic clusters that correspond with newly described Neotropical biogeographical regions: 1) Atlantic Forest province (= southeast population); 2) Parana Forest province (= West Atlantic forest population, with one Chacoan population - SP); and 3) Brazilian dominion population (= Amazonian population with one Chacoan population - TO). Significant levels of pairwise genetic divergences were found among the three clusters, allele sharing among clusters was negligible, and geographical distance did not contribute to differentiation. We infer that the Atlantic forest coastal mountain range limited dispersal between the Atlantic Forest province and the Parana Forest province populations, and that the large, diagonal open vegetation region of the Chacoan dominion dramatically reduced dispersal between the Parana and Brazilian dominion populations. We hypothesize that the three genetic clusters may represent three putative species. PMID:26172559

  8. Brazilian Anopheles darlingi Root (Diptera: Culicidae) Clusters by Major Biogeographical Region.

    PubMed

    Emerson, Kevin J; Conn, Jan E; Bergo, Eduardo S; Randel, Melissa A; Sallum, Maria Anice M

    2015-01-01

    The major drivers of the extensive biodiversity of the Neotropics are proposed to be geological and tectonic events together with Pliocene and Pleistocene environmental and climatic change. Geographical barriers represented by the rivers Amazonas/Solimões, the Andes and the coastal mountain ranges in eastern Brazil have been hypothesized to lead to diversification within the primary malaria vector, Anopheles (Nyssorhynchus) darlingi Root, which primarily inhabits rainforest. To test this biogeographical hypothesis, we analyzed 786 single nucleotide polymorphisms (SNPs) in 12 populations of An. darlingi from across the complex Brazilian landscape. Both model-based (STRUCTURE) and non-model-based (Principal Components and Discriminant Analysis) analysis of population structure detected three major genetic clusters that correspond with newly described Neotropical biogeographical regions: 1) Atlantic Forest province (= southeast population); 2) Parana Forest province (= West Atlantic forest population, with one Chacoan population - SP); and 3) Brazilian dominion population (= Amazonian population with one Chacoan population - TO). Significant levels of pairwise genetic divergences were found among the three clusters, allele sharing among clusters was negligible, and geographical distance did not contribute to differentiation. We infer that the Atlantic forest coastal mountain range limited dispersal between the Atlantic Forest province and the Parana Forest province populations, and that the large, diagonal open vegetation region of the Chacoan dominion dramatically reduced dispersal between the Parana and Brazilian dominion populations. We hypothesize that the three genetic clusters may represent three putative species.

  9. Near-infrared surface photometry and morphology in virgo cluster spiral galaxy nuclear regions

    NASA Astrophysics Data System (ADS)

    Rauscher, Bernard J.

    1995-04-01

    This paper presents very high spatial resolution (seeing 0.75 arcsec FWHM) K band surface photometry of 15 Virgo cluster spiral galaxy nuclear regions (radii less then 1 kpc). It presents B and I CCD images of 13 of these galaxies. The goals of the study were: (1) to begin to establish a K band baseline of normal spiral galaxy nuclear regions against which peculiar galaxies may be compared, (2) to provide better contsraints on N-body models, and (3) to complement near-infrared studies of large scale structure in spiral galaxies with very high resolution imaging of the important nuclear regions. The principle findings are (1) between 1/4 and 1/3 of these nuclear regions show K band evidence of traxiality, (2) approximately 1/2 of these galaxies have axisymmetric nuclear regions, and (3) NGC 4321 has a bar that is not detectable in the optical images.

  10. DMRT gene cluster analysis in the platypus: new insights into genomic organization and regulatory regions.

    PubMed

    El-Mogharbel, Nisrine; Wakefield, Matthew; Deakin, Janine E; Tsend-Ayush, Enkhjargal; Grützner, Frank; Alsop, Amber; Ezaz, Tariq; Marshall Graves, Jennifer A

    2007-01-01

    We isolated and characterized a cluster of platypus DMRT genes and compared their arrangement, location, and sequence across vertebrates. The DMRT gene cluster on human 9p24.3 harbors, in order, DMRT1, DMRT3, and DMRT2, which share a DM domain. DMRT1 is highly conserved and involved in sexual development in vertebrates, and deletions in this region cause sex reversal in humans. Sequence comparisons of DMRT genes between species have been valuable in identifying exons, control regions, and conserved nongenic regions (CNGs). The addition of platypus sequences is expected to be particularly valuable, since monotremes fill a gap in the vertebrate genome coverage. We therefore isolated and fully sequenced platypus BAC clones containing DMRT3 and DMRT2 as well as DMRT1 and then generated multispecies alignments and ran prediction programs followed by experimental verification to annotate this gene cluster. We found that the three genes have 58-66% identity to their human orthologues, lie in the same order as in other vertebrates, and colocate on 1 of the 10 platypus sex chromosomes, X5. We also predict that optimal annotation of the newly sequenced platypus genome will be challenging. The analysis of platypus sequence revealed differences in structure and sequence of the DMRT gene cluster. Multispecies comparison was particularly effective for detecting CNGs, revealing several novel potential regulatory regions within DMRT3 and DMRT2 as well as DMRT1. RT-PCR indicated that platypus DMRT1 and DMRT3 are expressed specifically in the adult testis (and not ovary), but DMRT2 has a wider expression profile, as it does for other mammals. The platypus DMRT1 expression pattern, and its location on an X chromosome, suggests an involvement in monotreme sexual development.

  11. Nucleus and cytoplasm segmentation in microscopic images using K-means clustering and region growing

    PubMed Central

    Sarrafzadeh, Omid; Dehnavi, Alireza Mehri

    2015-01-01

    Background: Segmentation of leukocytes acts as the foundation for all automated image-based hematological disease recognition systems. Most of the time, hematologists are interested in evaluation of white blood cells only. Digital image processing techniques can help them in their analysis and diagnosis. Materials and Methods: The main objective of this paper is to detect leukocytes from a blood smear microscopic image and segment them into their two dominant elements, nucleus and cytoplasm. The segmentation is conducted using two stages of applying K-means clustering. First, the nuclei are segmented using K-means clustering. Then, a proposed method based on region growing is applied to separate the connected nuclei. Next, the nuclei are subtracted from the original image. Finally, the cytoplasm is segmented using the second stage of K-means clustering. Results: The results indicate that the proposed method is able to extract the nucleus and cytoplasm regions accurately and works well even though there is no significant contrast between the components in the image. Conclusions: In this paper, a method based on K-means clustering and region growing is proposed in order to detect leukocytes from a blood smear microscopic image and segment its components, the nucleus and the cytoplasm. As region growing step of the algorithm relies on the information of edges, it will not able to separate the connected nuclei more accurately in poor edges and it requires at least a weak edge to exist between the nuclei. The nucleus and cytoplasm segments of a leukocyte can be used for feature extraction and classification which leads to automated leukemia detection. PMID:26605213

  12. Predicted emission lines from giant HII regions ionized by aging star clusters.

    NASA Astrophysics Data System (ADS)

    Garcia-Vargas, M. L.; Bressan, A.; Diaz, A. I.

    1995-07-01

    We have computed theoretical models of the emission line spectra of giant extragalactic HII regions (GEHR) in which a single star cluster is assumed to be responsible for the ionization. Ionizing clusters, of different masses and metallicities, were constructed assuming that they formed in a single burst and with a Salpeter Initial Mass Function. Their evolution was then followed in detail up to an age of 5.4Myr after which they lack the high energy photons needed to keep the regions ionized. The integrated spectral energy distribution of every cluster has been computed for a set of discrete ages representative of relevant phases of their evolution and have been processed by the photoionization code CLOUDY, in order to obtain the corresponding emission line spectra of the ionized gas at optical and infrared wavelengths. A wide range of initial compositions, spanning from about 1/20 (Z=0.001) to 2.5 solar (Z=0.05), and total masses, between about 1-6x10^4^Msun_ has been considered. Gas and stars are assumed to have the same metallicity and this has been taken into account both in the stellar evolution and atmosphere models and in the nebular gas producing a consistent set of models. In this paper we present the synthetic emission line spectra of the ionized regions which are discussed in detail in Garcia-Vargas et al. (1995).

  13. Proper motions and CCD photometry of stars in the region of the open cluster NGC 6866

    NASA Astrophysics Data System (ADS)

    Frolov, V. N.; Ananjevskaja, Yu. K.; Gorshanov, D. L.; Polyakov, E. V.

    2010-05-01

    We present the results of our comprehensive study of the Galactic open star cluster NGC 6866. The positions of stars in the investigated region have been obtained with the “Fantasy” automatic measuring machine from 10 plates of the normal astrograph at the Pulkovo Astronomical Observatory. The size of the investigated field is 40' × 40', the limiting magnitude is B ˜ 16{·/ m }6, and the maximum epoch difference is 79 yr. For 1202 field stars, we have determined the relative proper motions with an rms error of 2.5 mas yr-1. Out of them, 423 stars may be considered cluster members with a probability P > 70% according to the astrometric criterion. Photometric diagrams have been used as an additional criterion. We have performed two-color BV CCD photometry of stars with the Pulkovo ZA-320M mirror astrograph. The U magnitudes from the literature have also been used to construct the two-color diagrams. A total of 267 stars have turned out to be members of NGC 6866 according to the two criteria. We present refined physical parameters of the cluster and its age estimate (5.6 × 108 yr). The cluster membership of red and blue giants, variable, double, and multiple stars is considered. We have found an almost complete coincidence of the positions of one of the stars in the region (a cluster nonmember) and a soft X-ray source in the ROSAT catalog. The “Fantasy” automatic measuring machine is described in the Appendix.

  14. THE CLUSTERED NATURE OF STAR FORMATION. PRE-MAIN-SEQUENCE CLUSTERS IN THE STAR-FORMING REGION NGC 602/N90 IN THE SMALL MAGELLANIC CLOUD

    SciTech Connect

    Gouliermis, Dimitrios A.; Gennaro, Mario; Schmeja, Stefan; Dolphin, Andrew E.; Tognelli, Emanuele; Prada Moroni, Pier Giorgio

    2012-03-20

    Located at the tip of the wing of the Small Magellanic Cloud (SMC), the star-forming region NGC 602/N90 is characterized by the H II nebular ring N90 and the young cluster of pre-main-sequence (PMS) and early-type main-sequence stars NGC 602, located in the central area of the ring. We present a thorough cluster analysis of the stellar sample identified with Hubble Space Telescope/Advanced Camera for Surveys in the region. We show that apart from the central cluster low-mass PMS stars are congregated in 13 additional small, compact sub-clusters at the periphery of NGC 602, identified in terms of their higher stellar density with respect to the average background density derived from star counts. We find that the spatial distribution of the PMS stars is bimodal, with an unusually large fraction ({approx}60%) of the total population being clustered, while the remaining is diffusely distributed in the intercluster area, covering the whole central part of the region. From the corresponding color-magnitude diagrams we disentangle an age difference of {approx}2.5 Myr between NGC 602 and the compact sub-clusters, which appear younger, on the basis of comparison of the brighter PMS stars with evolutionary models, which we accurately calculated for the metal abundance of the SMC. The diffuse PMS population appears to host stars as old as those in NGC 602. Almost all detected PMS sub-clusters appear to be centrally concentrated. When the complete PMS stellar sample, including both clustered and diffused stars, is considered in our cluster analysis, it appears as a single centrally concentrated stellar agglomeration, covering the whole central area of the region. Considering also the hot massive stars of the system, we find evidence that this agglomeration is hierarchically structured. Based on our findings, we propose a scenario according to which the region NGC 602/N90 experiences an active clustered star formation for the last {approx}5 Myr. The central cluster NGC 602 was

  15. Regional spatially adaptive total variation super-resolution with spatial information filtering and clustering.

    PubMed

    Yuan, Qiangqiang; Zhang, Liangpei; Shen, Huanfeng

    2013-06-01

    Total variation is used as a popular and effective image prior model in the regularization-based image processing fields. However, as the total variation model favors a piecewise constant solution, the processing result under high noise intensity in the flat regions of the image is often poor, and some pseudoedges are produced. In this paper, we develop a regional spatially adaptive total variation model. Initially, the spatial information is extracted based on each pixel, and then two filtering processes are added to suppress the effect of pseudoedges. In addition, the spatial information weight is constructed and classified with k-means clustering, and the regularization strength in each region is controlled by the clustering center value. The experimental results, on both simulated and real datasets, show that the proposed approach can effectively reduce the pseudoedges of the total variation regularization in the flat regions, and maintain the partial smoothness of the high-resolution image. More importantly, compared with the traditional pixel-based spatial information adaptive approach, the proposed region-based spatial information adaptive total variation model can better avoid the effect of noise on the spatial information extraction, and maintains robustness with changes in the noise intensity in the super-resolution process.

  16. [Fuzzy cluster for analysis of the relationship between the structure of cephalosporins and immune cross-reaction].

    PubMed

    Hu, C Q; Jin, S H; Sun, X L; Ren, M D

    1990-09-01

    Six parameters (molecular negentropy, acidic group number, basic group number, proton donor group number, proton acceptor group number, and a ratio of C atomic group number to total atomic group number) for characterizing the structure of an antibody combining site in a R1 chain of cephalosporins were selected. Although 12 parameters characterized the site A and site B in a R1 chain were used in fuzzy cluster, Fischer weighting ratio (Fi) indicated that only 5 parameters, 4 of them characterized the structure of site A, play an important part in the cluster. Therefore it was speculated that the site A was the major combining site in the antigen-antibody interaction. According to the similarity of the R1 chains, cephalosporins could be clustered into 4 groups among which less cross-reaction took place. Using the "relative Hamming distance" of the R1 chains for description of their similarity, we found that the intensity of the cross-reaction assayed by immune tests had a close correlation with the "relative Hamming distance", so the distance was used for prediction of the intensity of the cross-reaction of cephalosporins.

  17. Unsupervised clustering for logo images using singular values region covariance matrices on Lie groups

    NASA Astrophysics Data System (ADS)

    Zhang, Xuguang; Zhang, Yun; Zhang, Jie; Chen, Shengyong; Chen, Dan; Li, Xiaoli

    2012-04-01

    Toward the unsupervised clustering for color logo images corrupted by noise, we propose a novel framework in which the logo images are described by a model called singular values based region covariance matrices (SVRCM), and the mean shift algorithm is performed on Lie groups for clustering covariance matrices. To decrease the influence of noise, we choose the larger singular values, which can better represent the original image and discard the smaller singular values. Therefore, the chosen singular values are grouped and fused by a covariance matrix to form a SVRCM model that can represent the correlation and variance between different singular value features to enhance the discriminating ability of the model. In order to cluster covariance matrices, which do not lie on Euclidean space, the mean shift algorithm is performed on manifolds by iteratively transforming points between the Lie group and Lie algebra. Experimental results on 38 categories of logo images demonstrate the superior performance of the proposed method whose clustering rate can be achieved at 88.55%.

  18. A spectroscopic census in young stellar regions: the σ Orionis cluster

    SciTech Connect

    Hernández, Jesús; Perez, Alice; Hernan, Ramírez; Calvet, Nuria; Hartmann, Lee; Briceño, Cesar; Olguin, Lorenzo; Contreras, Maria E.; Allen, Lori; Espaillat, Catherine

    2014-10-10

    We present a spectroscopic survey of the stellar population of the σ Orionis cluster. We have obtained spectral types for 340 stars. Spectroscopic data for spectral typing come from several spectrographs with similar spectroscopic coverage and resolution. More than half of the stars in our sample are members confirmed by the presence of lithium in absorption, strong Hα in emission or weak gravity-sensitive features. In addition, we have obtained high-resolution (R ∼ 34,000) spectra in the Hα region for 169 stars in the region. Radial velocities were calculated from this data set. The radial velocity distribution for members of the cluster is in agreement with previous work. Analysis of the profile of the Hα line and infrared observations reveals two binary systems or fast rotators that mimic the Hα width expected in stars with accretion disks. On the other hand, there are stars with optically thick disks and narrow Hα profiles not expected in stars with accretion disks. This contribution constitutes the largest homogeneous spectroscopic data set of the σ Orionis cluster to date.

  19. Infant immunization coverage in Italy: estimates by simultaneous EPI cluster surveys of regions. ICONA Study Group.

    PubMed Central

    Salmaso, S.; Rota, M. C.; Ciofi Degli Atti, M. L.; Tozzi, A. E.; Kreidl, P.

    1999-01-01

    In 1998, a series of regional cluster surveys (the ICONA Study) was conducted simultaneously in 19 out of the 20 regions in Italy to estimate the mandatory immunization coverage of children aged 12-24 months with oral poliovirus (OPV), diphtheria-tetanus (DT) and viral hepatitis B (HBV) vaccines, as well as optional immunization coverage with pertussis, measles and Haemophilus influenzae b (Hib) vaccines. The study children were born in 1996 and selected from birth registries using the Expanded Programme of Immunization (EPI) cluster sampling technique. Interviews with parents were conducted to determine each child's immunization status and the reasons for any missed or delayed vaccinations. The study population comprised 4310 children aged 12-24 months. Coverage for both mandatory and optional vaccinations differed by region. The overall coverage for mandatory vaccines (OPV, DT and HBV) exceeded 94%, but only 79% had been vaccinated in accord with the recommended schedule (i.e. during the first year of life). Immunization coverage for pertussis increased from 40% (1993 survey) to 88%, but measles coverage (56%) remained inadequate for controlling the disease; Hib coverage was 20%. These results confirm that in Italy the coverage of only mandatory immunizations is satisfactory. Pertussis immunization coverage has improved dramatically since the introduction of acellular vaccines. A greater effort to educate parents and physicians is still needed to improve the coverage of optional vaccinations in all regions. PMID:10593033

  20. Identification of clustered YY1 binding sites in Imprinting Control Regions

    SciTech Connect

    Kim, J D; Hinz, A; Bergmann, A; Huang, J; Ovcharenko, I; Stubbs, L; Kim, J

    2006-04-19

    Mammalian genomic imprinting is regulated by Imprinting Control Regions (ICRs) that are usually associated with tandem arrays of transcription factor binding sites. In the current study, the sequence features derived from a tandem array of YY1 binding sites of Peg3-DMR (differentially methylated region) led us to identify three additional clustered YY1 binding sites, which are also localized within the DMRs of Xist, Tsix, and Nespas. These regions have been shown to play a critical role as ICRs for the regulation of surrounding genes. These ICRs have maintained a tandem array of YY1 binding sites during mammalian evolution. The in vivo binding of YY1 to these regions is allele-specific and only to the unmethylated active alleles. Promoter/enhancer assays suggest that a tandem array of YY1 binding sites function as a potential orientation-dependent enhancer. Insulator assays revealed that the enhancer-blocking activity is detected only in the YY1 binding sites of Peg3-DMR but not in the YY1 binding sites of other DMRs. Overall, our identification of three additional clustered YY1 binding sites in imprinted domains suggests a significant role for YY1 in mammalian genomic imprinting.

  1. Engineering a regulatory region of jadomycin gene cluster to improve jadomycin B production in Streptomyces venezuelae.

    PubMed

    Zheng, Jian-Ting; Wang, Sheng-Lan; Yang, Ke-Qian

    2007-09-01

    Streptomyces venezuelae ISP5230 produces a group of jadomycin congeners with cytotoxic activities. To improve jadomycin fermentation process, a genetic engineering strategy was designed to replace a 3.4-kb regulatory region of jad gene cluster that contains four regulatory genes (3' end 272 bp of jadW2, jadW3, jadR2, and jadR1) and the native promoter upstream of jadJ (P(J)) with the ermEp* promoter sequence so that ermEp* drives the expression of the jadomycin biosynthetic genes from jadJ in the engineered strain. As expected, the mutant strain produced jadomycin B without ethanol treatment, and the yield increased to about twofold that of the stressed wild-type. These results indicated that manipulation of the regulation of a biosynthetic gene cluster is an effective strategy to increase product yield.

  2. Deep UV Luminosity Functions at the Infall Region of the Coma Cluster

    NASA Technical Reports Server (NTRS)

    Hammer, D. M.; Hornschemeier, A. E.; Salim, S.; Smith, R.; Jenkins, L.; Mobasher, B.; Miller, N.; Ferguson, H.

    2011-01-01

    We have used deep GALEX observations at the infall region of the Coma cluster to measure the faintest UV luminosity functions (LFs) presented for a rich galaxy cluster thus far. The Coma UV LFs are measured to M(sub uv) = -10.5 in the GALEX FUV and NUV bands, or 3.5 mag fainter than previous studies, and reach the dwarf early-type galaxy population in Coma for the first time. The Schechter faint-end slopes (alpha approximately equal to -1.39 in both GALEX bands) are shallower than reported in previous Coma UV LF studies owing to a flatter LF at faint magnitudes. A Gaussian-plus-Schechter model provides a slightly better parametrization of the UV LFs resulting in a faint-end slope of alpha approximately equal to -1.15 in both GALEX bands. The two-component model gives faint-end slopes shallower than alpha = -1 (a turnover) for the LFs constructed separately for passive and star forming galaxies. The UV LFs for star forming galaxies show a turnover at M(sub UV) approximately equal to -14 owing to a deficit of dwarf star forming galaxies in Coma with stellar masses below M(sub *) = 10(sup 8) solar mass. A similar turnover is identified in recent UV LFs measured for the Virgo cluster suggesting this may be a common feature of local galaxy clusters, whereas the field UV LFs continue to rise at faint magnitudes. We did not identify an excess of passive galaxies as would be expected if the missing dwarf star forming galaxies were quenched inside the cluster. In fact, the LFs for both dwarf passive and star forming galaxies show the same turnover at faint magnitudes. We discuss the possible origin of the missing dwarf star forming galaxies in Coma and their expected properties based on comparisons to local field galaxies.

  3. Proper motions and membership probabilities of stars in the region of globular cluster NGC 6366

    NASA Astrophysics Data System (ADS)

    Sariya, Devesh P.; Yadav, R. K. S.

    2015-12-01

    Context. NGC 6366 is a metal-rich globular cluster that is relatively unstudied. It is a kinematically interesting cluster, reported as belonging to the slowly rotating halo system, which is unusual given its metallicity and spatial location in the Galaxy. Aims: The purpose of this research is to determine the relative proper motion and membership probability of the stars in the region of globular cluster NGC 6366. To target cluster members reliably during spectroscopic surveys without including field stars, a good proper motion and membership probability catalogue of NGC 6366 is needed. Methods: To derive relative proper motions, the archival data from the Wide Field Imager mounted on the ESO 2.2 m telescope have been reduced using a high precision astrometric software. The images used are in the B,V, and I photometric bands with an epoch gap of ~3.2 yr. The calibrated BVI magnitudes have been determined using recent data for secondary standard stars. Results: We determined relative proper motions and cluster membership probabilities for 2530 stars in the field of globular cluster NGC 6366. The median proper motion rms errors for stars brighter than V ~ 18 mag is ~2 mas yr-1, which gradually increases to ~5 mas yr-1 for stars having magnitudes V ~ 20 mag. Based on the membership catalogue, we checked the membership status of the X-ray sources and variable stars of NGC 6366 mentioned in the literature. We also provide the astronomical community with an electronic catalogue that includes B, V, and I magnitudes; relative proper motions; and membership probabilities of the stars in the region of NGC 6366. Based on observations with the MPG/ESO 2.2 m and ESO/VLT telescopes, located at La Silla and Paranal Observatory, Chile, under DDT programs 164.O-0561(F), 71.D-0220(A) and the archive material.Full Table 4 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/584/A59

  4. Equation-Of Coupled-Cluster Calculations of Photodetachment Cross Sections for Atomic Negative Ions across the Periodic Table

    NASA Astrophysics Data System (ADS)

    Ichino, Takatoshi; Cheng, Lan; Stanton, John F.

    2016-06-01

    The innovative application of the ion-trap technique by Wester and coworkers has yielded definitive experimental values of photodetachment cross sections for the atomic oxygen radical anion (Obullet -) [Hlavenka et al., J. Chem. Phys. 130, 061105 (2009)]. In the present study, equation-of-motion coupled-cluster (EOM-CC) calculations have been performed to derive theoretical values of photodetachment cross sections for the negative ions of atoms in the first two periods of the periodic table as well as of those which belong to the alkali metal and halogen groups. Two methods have been employed to derive the cross sections. One involves the Dyson orbitals obtained from EOM-CC calculations and plane wave functions for the detached electron in the transition dipole moment integrals. The other method utilizes the moment theory following EOM-CC calculations of transition dipole moments for a large number of pseudo-states. The cross sections so evaluated for Obullet - match the experimental values very well. Generally good agreement has been found between the theoretical and experimental values of the cross sections for the atoms in the first two periods, while the present calculations cast some doubt on reported experimental values for some atoms beyond the second period. Substantial relativistic effects on the cross section have been observed for heavy elements in the alkali metal and halogen groups.

  5. Failure of lysosome clustering and positioning in the juxtanuclear region in cells deficient in rapsyn

    PubMed Central

    Aittaleb, Mohamed; Chen, Po-Ju; Akaaboune, Mohammed

    2015-01-01

    ABSTRACT Rapsyn, a scaffold protein, is required for the clustering of acetylcholine receptors (AChRs) at contacts between motor neurons and differentiating muscle cells. Rapsyn is also expressed in cells that do not express AChRs. However, its function in these cells remains unknown. Here, we show that rapsyn plays an AChR-independent role in organizing the distribution and mobility of lysosomes. In cells devoid of AChRs, rapsyn selectively induces the clustering of lysosomes at high density in the juxtanuclear region without affecting the distribution of other intracellular organelles. However, when the same cells overexpress AChRs, rapsyn is recruited away from lysosomes to colocalize with AChR clusters on the cell surface. In rapsyn-deficient (Rapsn−/−) myoblasts or cells overexpressing rapsyn mutants, lysosomes are scattered within the cell and highly dynamic. The increased mobility of lysosomes in Rapsn−/− cells is associated with a significant increase in lysosomal exocytosis, as evidenced by increased release of lysosomal enzymes and plasma membrane damage when cells were challenged with the bacterial pore-forming toxin streptolysin-O. These findings uncover a new link between rapsyn, lysosome positioning, exocytosis and plasma membrane integrity. PMID:26330529

  6. Eastern region represents a worrying cluster of active hepatitis C in Algeria in 2012.

    PubMed

    Bensalem, Aïcha; Selmani, Karima; Hihi, Narjes; Bencherifa, Nesrine; Mostefaoui, Fatma; Kerioui, Cherif; Pineau, Pascal; Debzi, Nabil; Berkane, Saadi

    2016-08-01

    Algeria is the largest country of Africa, peopled with populations living a range of traditional/rural and modern/urban lifestyles. The variations of prevalence of chronic active hepatitis care poorly known on the Algerian territory. We conducted a retrospective survey on all patients (n = 998) referred to our institution in 2012 and confirmed by us for an active hepatitis C. Half of the hepatitis C virus (HCV) isolates were genotyped. Forty Algerian regions out of the 48 were represented in our study. Three geographical clusters (Aïn-Temouchent/SidiBelAbbes, Algiers, and a large Eastern region) with an excess of active hepatitis C were observed. Patients coming from the Eastern cluster (Batna, Khenchela, Oum el Bouaghi, and Tebessa) were strongly over-represented (49% of cases, OR = 14.5, P < 0.0001). The hallmarks of Eastern region were an excess of women (65% vs. 46% in the remaining population, P < 0.0001) and the almost exclusive presence of HCV genotype 1 (93% vs. 63%, P = 0.0001). The core of the epidemics was apparently located in Khenchela (odds ratio = 24.6, P < 0.0001). This situation is plausibly connected with nosocomial transmission or traditional practices as scarification (Hijama), piercing or tattooing, very lively in this region. Distinct hepatitis C epidemics are currently affecting Algerian population. The most worrying situation is observed in rural regions located east of Algeria. J. Med. Virol. 88:1394-1403, 2016. © 2016 Wiley Periodicals, Inc.

  7. HST Snapshot Study of Variable Stars in Globular Clusters: Inner Region of NGC 6441

    NASA Technical Reports Server (NTRS)

    Pritzl, Barton J.; Smith, Horace A.; Stetson, Peter B.; Catelan, Marcio; Sweigart, Allen V.; Layden, Andrew C.; Rich, R. Michael

    2003-01-01

    We present the results of a Hubble Space Telescope snapshot program to survey the inner region of the metal-rich globular cluster NGC 6441 for its variable stars. A total of 57 variable stars was found including 38 RR Lyrae stars, 6 Population II Cepheids, and 12 long period variables. Twenty-four of the RR Lyrae stars and all of the Population II Cepheids were previously undiscovered in ground-based surveys. Of the RR Lyrae stars observed in h s survey, 26 are pulsating in the fundamental mode with a mean period of 0.753 d and 12 are first-overtone mode pulsators with a mean period of 0.365 d. These values match up very well with those found in ground-based surveys. Combining all the available data for NGC 6441, we find mean periods of 0.759 d and 0.375 d for the RRab and RRc stars, respectively. We also find that the RR Lyrae in this survey are located in the same regions of a period-amplitude diagram as those found in ground-based surveys. The overall ratio of RRc to total RR Lyrae is 0.33. Although NGC 6441 is a metal-rich globular cluster and would, on that ground, be expected either to have few RR Lyrae stars, or to be an Oosterhoff type I system, its RR Lyrae more closely resemble those in Oosterhoff type II globular clusters. However, even compared to typical Oosterhoff type II systems, the mean period of its RRab stars is unusually long. We also derived I-band period-luminosity relations for the RR Lyrae stars. Of the six Population II Cepheids, five are of W Virginis type and one is a BL Herculis variable star. This makes NGC 6441, along with NGC 6388, the most metal-rich globular cluster known to contain these types of variable stars. Another variable, V118, may also be a Population II Cepheid given its long period and its separation in magnitude from the RR Lyrae stars. We examine the period-luminosity relation for these Population II Cepheids and compare it to those in other globular clusters and in the Large Magellanic Cloud. We argue that there does

  8. Proper motions and CCD-photometry of stars in the region of the open cluster Trumpler 2

    NASA Astrophysics Data System (ADS)

    Frolov, V. N.; Ananjevskaja, J. K.; Jilinski, E. G.; Gorshanov, D. L.; Bronnikova, N. M.

    2006-06-01

    The results of a complex study of the galactic open cluster Trumpler 2 are presented. In order to obtain the proper motions, the positions of approximately 3000 stars up to the limit magnitude B˜16.25 mag in the area 80 arcmin×80 arcmin around the cluster were measured on 6 plates with a maximal epoch difference of 63 years. The root-mean error of the relative proper motions is 4.2 mas yr-1. The catalogue of {BV} magnitudes of all the stars in the investigated area was compiled. The selection of the cluster members within the region of R<16 arcmin from the center of the cluster was made. Altogether, 148 stars were considered to be cluster members by both astrometrical and photometrical criteria. We present the estimated age (8.91×107 yr) and physical parameters of the cluster and append the catalogues of the proper motions and of the photometry of the stars.

  9. Probing Electronic Wave Functions of Sodium-Doped Clusters: Dyson Orbitals, Anisotropy Parameters, and Ionization Cross-Sections.

    PubMed

    Gunina, Anastasia O; Krylov, Anna I

    2016-12-15

    We apply high-level ab initio methods to describe the electronic structure of small clusters of ammonia and dimethyl ether (DME) doped with sodium, which provide a model for solvated electrons. We investigate the effect of the solvent and cluster size on the electronic states. We consider both energies and properties, with a focus on the shape of the electronic wave function and the related experimental observables such as photoelectron angular distributions. The central quantity in modeling photoionization experiments is the Dyson orbital, which describes the difference between the initial N-electron and final (N-1)-electron states of a system. Dyson orbitals enter the expression of the photoelectron matrix element, which determines total and partial photoionization cross-sections. We compute Dyson orbitals for the Na(NH3)n and Na(DME)m clusters using correlated wave functions (obtained with equation-of-motion coupled-cluster model for electron attachment with single and double substitutions) and compare them with more approximate Hartree-Fock and Kohn-Sham orbitals. We also analyze the effect of correlation and basis sets on the shapes of Dyson orbitals and the experimental observables.

  10. Probing electronic wave functions of sodium-doped clusters: Dyson orbitals, anisotropy parameters, and ionization cross-sections

    SciTech Connect

    Gunina, Anastasia O.; Krylov, Anna I.

    2016-11-14

    We apply high-level ab initio methods to describe the electronic structure of small clusters of ammonia and dimethylether (DME) doped with sodium, which provide a model for solvated electrons. We investigate the effect of the solvent and cluster size on the electronic states. We consider both energies and properties, with a focus on the shape of the electronic wave function and the related experimental observables such as photoelectron angular distributions. The central quantity in modeling photoionization experiments is the Dyson orbital, which describes the difference between the initial N-electron and final (N-1)-electron states of a system. Dyson orbitals enter the expression of the photoelectron matrix element, which determines total and partial photoionization cross-sections. We compute Dyson orbitals for the Na(NH3)n and Na(DME)m clusters using correlated wave functions (obtained with equation-of-motion coupled-cluster model for electron attachment with single and double substitutions) and compare them with more approximate Hartree-Fock and Kohn-Sham orbitals. As a result, we also analyze the effect of correlation and basis sets on the shapes of Dyson orbitals and the experimental observables.

  11. Probing electronic wave functions of sodium-doped clusters: Dyson orbitals, anisotropy parameters, and ionization cross-sections

    DOE PAGES

    Gunina, Anastasia O.; Krylov, Anna I.

    2016-11-14

    We apply high-level ab initio methods to describe the electronic structure of small clusters of ammonia and dimethylether (DME) doped with sodium, which provide a model for solvated electrons. We investigate the effect of the solvent and cluster size on the electronic states. We consider both energies and properties, with a focus on the shape of the electronic wave function and the related experimental observables such as photoelectron angular distributions. The central quantity in modeling photoionization experiments is the Dyson orbital, which describes the difference between the initial N-electron and final (N-1)-electron states of a system. Dyson orbitals enter themore » expression of the photoelectron matrix element, which determines total and partial photoionization cross-sections. We compute Dyson orbitals for the Na(NH3)n and Na(DME)m clusters using correlated wave functions (obtained with equation-of-motion coupled-cluster model for electron attachment with single and double substitutions) and compare them with more approximate Hartree-Fock and Kohn-Sham orbitals. As a result, we also analyze the effect of correlation and basis sets on the shapes of Dyson orbitals and the experimental observables.« less

  12. Study of waves in the magnetotail region with cluster and DSP

    NASA Astrophysics Data System (ADS)

    Volwerk, M.; Zhang, T. L.; Glassmeier, K. H.; Runov, A.; Baumjohann, W.; Balogh, A.; Rème, H.; Klecker, B.; Carr, C.

    The study of the neutral sheet is of fundamental importance in understanding the dynamics of the Earth’s magnetosphere. From the earliest observation of the magnetotail, it has been found that the neutral sheet frequently appears to be in motion due to changing solar wind conditions and geomagnetic activity. Multiple crossings of the neutral sheet by spacecraft have been attributed to a flapping motion of the neutral sheet in the north south direction, a wavy profile either along the magnetotail or the dawn dusk direction. Cluster observations have revealed that the flapping motions of the Earth’s magnetotail are of internal origin and that kink-like waves are emitted from the central part of the tail and propagate toward the tail flanks. This flapping motion is shown here to propagate at an angle of ˜45° with xGSM. A possible assumption that the flapping could be created by a wake travelling away from a fast flow in the current sheet is rejected. Other waves in the magnetotail are found in the ULF range. One conjunction event between Cluster and DoubleStar TC1 is presented where all spacecraft show ULF wave activity at a period of approximately 5 min during fast Earthward flow. These waves are shown to be Kelvin Helmholtz waves on the boundaries of the flow channel. Calculations show that the conversion of flow energy into magnetic energy through the Kelvin Helmholtz instability can contribute to a significant part of flow breaking between Cluster and DoubleStar TC1.

  13. A new methodology to define homogeneous regions through an entropy based clustering method

    NASA Astrophysics Data System (ADS)

    Ridolfi, E.; Rianna, M.; Trani, G.; Alfonso, L.; Di Baldassarre, G.; Napolitano, F.; Russo, F.

    2016-10-01

    One of the most crucial steps in flow frequency studies is the definition of Homogenous Regions (HRs), i.e. areas with similar hydrological behavior. This is essential in ungauged catchments, as HR allows information to be transferred from a neighboring river basin. This study proposes a new, entropy-based approach to define HRs, in which regions are defined as homogeneous if their hydrometric stations capture redundant information. The problem is handled through the definition of the Information Transferred Index (ITI) as the ratio between redundant information and the total information provided by pairs of stations. The methodology is compared with a traditional, distance-based clustering method through a Monte Carlo experiment and a jack-knife procedure. Results indicate that the ITI-based method performs well, adding value to current methodologies to define HRs.

  14. Toward an SSC test lattice design with two chromatic clusters of interaction regions

    SciTech Connect

    Garren, A.; Steffen, K.

    1985-10-01

    Various ideas on how to design a cluster of interaction regions (IR) with local chromaticity correction were investigated, all of them employing pairs of sextupoles with betatron phase advances of (2n+{lambda}){pi} between them so that their geometric aberrations cancel. Some of these ideas were discarded. Even when, at the sextupoles, one amplitude function is made very small as compared to the other, and the two interleaving pairs are thus decoupled regarding their horizontal and vertical chromaticity correction, they can still not be considered `non-interleaved` regarding their compensation of chromatic aberrations. What remains, then, are schemes that have one or more complete sextupole pairs in a periodic focusing structure between interaction points. This periodic structure may be specially tailored to suit the purpose, or it may even be the normal arc FODO structure. In any case, it must have a strong horizontal dispersion for the sextupoles to act on. Probably the best and most elegant structure the authors found is the one described at the end of this note; it has a 2200 m long periodic channel of arc cells with four pairs of sextupoles between interaction points. In this scheme, the three interaction points forming a `cluster` are within five miles of each other, and thus the denotation may still be justified. However, the FODO channels may be increased in this scheme to any length, until an equidistant spacing of IR`s is obtained. The elegance of the scheme lies in the way the vertical separation and the horizontal and vertical dispersions are handled at the end of the FODO channel and matched into the interaction region, and it is applicable to clustered as well as distributed IR`s. However at first a simpler scheme will be described which has only one pair of sextupoles between IR`s, placed in a specially tailored FODO channel with long cells and very large dispersion.

  15. A novel method for discovering local spatial clusters of genomic regions with functional relationships from DNA contact maps

    PubMed Central

    Hu, Xihao; Shi, Christina Huan; Yip, Kevin Y.

    2016-01-01

    Motivation: The three-dimensional structure of genomes makes it possible for genomic regions not adjacent in the primary sequence to be spatially proximal. These DNA contacts have been found to be related to various molecular activities. Previous methods for analyzing DNA contact maps obtained from Hi-C experiments have largely focused on studying individual interactions, forming spatial clusters composed of contiguous blocks of genomic locations, or classifying these clusters into general categories based on some global properties of the contact maps. Results: Here, we describe a novel computational method that can flexibly identify small clusters of spatially proximal genomic regions based on their local contact patterns. Using simulated data that highly resemble Hi-C data obtained from real genome structures, we demonstrate that our method identifies spatial clusters that are more compact than methods previously used for clustering genomic regions based on DNA contact maps. The clusters identified by our method enable us to confirm functionally related genomic regions previously reported to be spatially proximal in different species. We further show that each genomic region can be assigned a numeric affinity value that indicates its degree of participation in each local cluster, and these affinity values correlate quantitatively with DNase I hypersensitivity, gene expression, super enhancer activities and replication timing in a cell type specific manner. We also show that these cluster affinity values can precisely define boundaries of reported topologically associating domains, and further define local sub-domains within each domain. Availability and implementation: The source code of BNMF and tutorials on how to use the software to extract local clusters from contact maps are available at http://yiplab.cse.cuhk.edu.hk/bnmf/. Contact: kevinyip@cse.cuhk.edu.hk Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27307607

  16. On the Origin of the HII Regions Associated with Massive and Compact Superstar Clusters

    NASA Astrophysics Data System (ADS)

    Silich, Sergiy; Tenorio-Tagle, Guillermo; Muñoz-Tuñón, Casiana

    This contribution to the IV Korea-Mexico meeting deals with the hydrodynamics of the matter reinserted within super star clusters (SSCs) by both stellar winds and supernova explosions, results recently printed in The Astrophysical Journal (Silich et al. 2007). The motivation of such a project arose from the persistent presence of the small mass and compact HII regions that sit right on top of many massive and compact SSCs, from which one expects a large mechanical energy power. The data used for our calculations appear only recently (see Smith et al. 2006) for the massive and compact SSC M82-A1. We presented in our paper the calculated flow, derived through analytical and semi-analytical methods, which led to almost identical results. We have found out that the only way of accommodating a compact HII region (4.5 pc in radius, in the case of M82-A1) on top of a 6.3 Myr old and massive (> 10^6 M_{⊙}) SSC with a half light radius of 3 pc, requires of two assumptions: a very low heating efficiency (< 10%) within the cluster, what leads to a bimodal solution (see Tenorio-Tagle et al. 2007) and a high pressure in the surrounding medium.

  17. The Radial Mass Profile within the Entire Virial Region of a Fossil Cluster

    NASA Astrophysics Data System (ADS)

    Buote, David A.; Su, Yuanyuan; Gastaldello, Fabio; Brighenti, Fabrizio

    2016-06-01

    We present a hydrostatic analysis of the azimuthally averaged hot intracluster medium (ICM) of the entire virial region of the relaxed fossil cluster RXJ 1159+5531. For a model consisting of ICM, stellar mass from the central galaxy (BCG), and an NFW dark matter (DM) halo, we obtain a good description of the projected radial profiles of ICM temperature and emission-measure that yield precise constraints on the total mass profile. The BCG stellar mass component is clearly detected with a K-band stellar mass-to-light ratio, M_star/L_K = 0.61 +/- 0.11 solar, consistent with stellar population synthesis models. We obtain a halo concentration, c_200 = 8.4 +/- 1.0, and virial mass, M_200 = 7.9 +/- 0.6 x 10^{13} M_sun. For its mass, the inferred concentrationis larger than most relaxed halos produced in cosmological simulations with Planck parameters, consistent with RXJ 1159+5531 forming earlier than the general halo population. The detection of a plausible stellar BCG mass component distinct from the NFW DM halo in the total gravitational potential supports the suggestion by Newman et al. (2015) that 10^{14} M_sun represents the mass scale above which dissipation is unimportant in the formation of the central regions of galaxy clusters.

  18. Enhanced performance of anion exchange membranes via crosslinking of ion cluster regions for fuel cells

    NASA Astrophysics Data System (ADS)

    Lai, Ao Nan; Guo, Dong; Lin, Chen Xiao; Zhang, Qiu Gen; Zhu, Ai Mei; Ye, Mei Ling; Liu, Qing Lin

    2016-09-01

    Development of anion exchange membranes (AEMs) with high hydroxide conductivity, good dimensional and alkaline stabilities is still a challenge for the practical application of AEM fuel cells. In this study, we report a new strategy to prepare high-performance AEMs with crosslinked ionic regions. A series of phenolphthalein-containing poly(arylene ether sulfone)s crosslinked AEMs was synthesized by grafting ion groups selectively and densely on the phenolphthalein units to form ion clusters that are further crosslinked to generate the hydrophilic ionic regions. The crosslinking reaction not only improved the dimensional stability of the AEMs, but also increased the aggregation of the ion clusters leading to the formation of hydrophilic/hydrophobic phase-separated morphology and ion-conducting channels. As a result, enhancements in both ion conductivity and dimensional stability can be achieved. The crosslinked AEMs showed high hydroxide conductivities in the range of 52.2-143.4 mS cm-1 from 30 to 80 °C and a superb ratio of relative conductivity to relative swelling at 80 °C. Furthermore, the crosslinked AEMs also exhibited good mechanical properties, thermal and alkaline stabilities and desirable single cell performance. This work presents a promising strategy for the synthesis of high-performance AEMs for fuel cells.

  19. Employing post-DEA cross-evaluation and cluster analysis in a sample of Greek NHS hospitals.

    PubMed

    Flokou, Angeliki; Kontodimopoulos, Nick; Niakas, Dimitris

    2011-10-01

    To increase Data Envelopment Analysis (DEA) discrimination of efficient Decision Making Units (DMUs), by complementing "self-evaluated" efficiencies with "peer-evaluated" cross-efficiencies and, based on these results, to classify the DMUs using cluster analysis. Healthcare, which is deprived of such studies, was chosen as the study area. The sample consisted of 27 small- to medium-sized (70-500 beds) NHS general hospitals distributed throughout Greece, in areas where they are the sole NHS representatives. DEA was performed on 2005 data collected from the Ministry of Health and the General Secretariat of the National Statistical Service. Three inputs -hospital beds, physicians and other health professionals- and three outputs -case-mix adjusted hospitalized cases, surgeries and outpatient visits- were included in input-oriented, constant-returns-to-scale (CRS) and variable-returns-to-scale (VRS) models. In a second stage (post-DEA), aggressive and benevolent cross-efficiency formulations and clustering were employed, to validate (or not) the initial DEA scores. The "maverick index" was used to sort the peer-appraised hospitals. All analyses were performed using custom-made software. Ten benchmark hospitals were identified by DEA, but using the aggressive and benevolent formulations showed that two and four of them respectively were at the lower end of the maverick index list. On the other hand, only one 100% efficient (self-appraised) hospital was at the higher end of the list, using either formulation. Cluster analysis produced a hierarchical "tree" structure which dichotomized the hospitals in accordance to the cross-evaluation results, and provided insight on the two-dimensional path to improving efficiency. This is, to our awareness, the first study in the healthcare domain to employ both of these post-DEA techniques (cross efficiency and clustering) at the hospital (i.e. micro) level. The potential benefit for decision-makers is the capability to examine high

  20. Waveform cross correlation at the International Data Centre: comparison with Reviewed Event Bulletin and regional catalogues

    NASA Astrophysics Data System (ADS)

    Kitov, Ivan; Bobrov, Dmitry; Rozhkov, Mikhail; Johansson, Peder

    2013-04-01

    Waveform cross correlation substantially improves detection, phase association, and event building procedures at the International Data Centre (IDC) of the Comprehensive Nuclear-Test-Ban Treaty Organization. There were 50% to 100% events extra to the official Reviewed Event Bulletin (REB) were found in the aftershock sequences of small, middle size, and very big earthquakes. Several per cent of the events reported in the REB were not found with cross correlation even when all aftershocks were used as master events. These REB events are scrutinized in interactive analysis in order to reveal the reason of the cross correlation failure. As a corroborative method, we use detailed regional catalogues, which often include aftershocks with magnitudes between 2.0 and 3.0. Since the resolution of regional networks is by at least one unit of magnitude higher, the REB events missed from the relevant regional catalogues are considered as bogus. We compare events by origin time and location because the regional networks and the International Monitoring System are based on different sets of seismic stations and phase comparison is not possible. Three intracontinental sequences have been studied: after the March 20, 2008 earthquake in China (mb(IDC)=5.4), the May 20, 2012 event in Italy (mb(IDC)=5.3), and one earthquake (mb(IDC)=5.6) in Virginia, USA (August 23, 2011). Overall, most of the events not found by cross correlation are missing from the relevant regional catalogues. At the same time, these catalogues confirm most of additional REB events found only by cross correlation. This observation supports all previous findings of the improved quality of events built by cross correlation.

  1. Nonlinear functional connectivity network recovery in the human brain with mutual connectivity analysis (MCA): convergent cross-mapping and non-metric clustering

    NASA Astrophysics Data System (ADS)

    Wismüller, Axel; Abidin, Anas Z.; D'Souza, Adora M.; Wang, Xixi; Hobbs, Susan K.; Leistritz, Lutz; Nagarajan, Mahesh B.

    2015-03-01

    We explore a computational framework for functional connectivity analysis in resting-state functional MRI (fMRI) data acquired from the human brain for recovering the underlying network structure and understanding causality between network components. Termed mutual connectivity analysis (MCA), this framework involves two steps, the first of which is to evaluate the pair-wise cross-prediction performance between fMRI pixel time series within the brain. In a second step, the underlying network structure is subsequently recovered from the affinity matrix using non-metric network clustering approaches, such as the so-called Louvain method. Finally, we use convergent cross-mapping (CCM) to study causality between different network components. We demonstrate our MCA framework in the problem of recovering the motor cortex network associated with hand movement from resting state fMRI data. Results are compared with a ground truth of active motor cortex regions as identified by a task-based fMRI sequence involving a finger-tapping stimulation experiment. Our results regarding causation between regions of the motor cortex revealed a significant directional variability and were not readily interpretable in a consistent manner across subjects. However, our results on whole-slice fMRI analysis demonstrate that MCA-based model-free recovery of regions associated with the primary motor cortex and supplementary motor area are in close agreement with localization of similar regions achieved with a task-based fMRI acquisition. Thus, we conclude that our MCA methodology can extract and visualize valuable information concerning the underlying network structure between different regions of the brain in resting state fMRI.

  2. Exotic clusters in an unbound region of light neutron-rich systems

    NASA Astrophysics Data System (ADS)

    Ito, Makoto

    2009-10-01

    In light neutron-rich systems, many kinds of molecular structures are discussed from the view point of the clustering phenomena.In particular, much attention has been concentrated on Be isotopes. The molecular orbital (MO), such as &-circ; and &+circ; associated with the covalent binding of atomic molecules, have been shown to give a good description for the low-lying states of these isotopes. In their highly-excited states, furthermore, recent experiments revealed the existence of the interesting resonant states which dominantly decay to the ^6,8He fragments. In this report, we show the unified study of the exotic structures of ^12Be=α+α+4N in an unbound region and the α+^6,8He resonant scattering. We applied the generalized two-center cluster model in which the covalent MO and the atomic orbital (AO) configurations with ^xHe+^yHe could be described in a unified manner. First, we calculated the energy spectra below an α decay-threshold. The (π32^-)^2 (σ12^+)^2 configuration corresponding to ν(0p)^4(sd)^2 becomes the ground state, while (π3 2^-)^2(π12^-)^2 having a large overlap with ν(0p)^6 appears as the first excited state. The rotational band of the ground state reaches to the maximum spin of J^π = 8^+. This result means that the magicity of N=8 is broken in ^12Be due to the formation of (π3 2^-)^2(σ12^+)^2. Next, we solved the scattering problem of α+^8He and identified the several resonance poles. In the continuum region, we found the rotational bands having the AO configurations of α+^8He, ^6He+^6He, and ^5He+^7 He. Furthermore, a much more exotic band appears in the same energy region. In this band, two valence neutrons are localized at individual α-cores (the ^5He+^5He cluster), while the other two neutrons form the covalent &+circ;- bonding between two ^5He clusters; hence, it has a ``hybrid structure'' between the MO configuration and the AO one. In the J^π=0^+ state, it is strongly excited by the two-neutron transfer reaction, α+^8He

  3. Automated regional registration and characterization of corresponding microcalcification clusters on temporal pairs of mammograms for interval change analysis

    SciTech Connect

    Filev, Peter; Hadjiiski, Lubomir; Chan, Heang-Ping; Sahiner, Berkman; Ge Jun; Helvie, Mark A.; Roubidoux, Marilyn; Zhou Chuan

    2008-12-15

    A computerized regional registration and characterization system for analysis of microcalcification clusters on serial mammograms is being developed in our laboratory. The system consists of two stages. In the first stage, based on the location of a detected cluster on the current mammogram, a regional registration procedure identifies the local area on the prior that may contain the corresponding cluster. A search program is used to detect cluster candidates within the local area. The detected cluster on the current image is then paired with the cluster candidates on the prior image to form true (TP-TP) or false (TP-FP) pairs. Automatically extracted features were used in a newly designed correspondence classifier to reduce the number of false pairs. In the second stage, a temporal classifier, based on both current and prior information, is used if a cluster has been detected on the prior image, and a current classifier, based on current information alone, is used if no prior cluster has been detected. The data set used in this study consisted of 261 serial pairs containing biopsy-proven calcification clusters. An MQSA radiologist identified the corresponding clusters on the mammograms. On the priors, the radiologist rated the subtlety of 30 clusters (out of the 261 clusters) as 9 or 10 on a scale of 1 (very obvious) to 10 (very subtle). Leave-one-case-out resampling was used for feature selection and classification in both the correspondence and malignant/benign classification schemes. The search program detected 91.2%(238/261) of the clusters on the priors with an average of 0.42 FPs/image. The correspondence classifier identified 86.6%(226/261) of the TP-TP pairs with 20 false matches (0.08 FPs/image) relative to the entire set of 261 image pairs. In the malignant/benign classification stage the temporal classifier achieved a test A{sub z} of 0.81 for the 246 pairs which contained a detection on the prior. In addition, a classifier was designed by using the

  4. Functional definition of the mutation cluster region of adenomatous polyposis coli in colorectal tumours.

    PubMed

    Kohler, Eva Maria; Derungs, Adrian; Daum, Gabriele; Behrens, Jürgen; Schneikert, Jean

    2008-07-01

    The mutation cluster region (MCR) of adenomatous polyposis coli (APC) is located within the central part of the open reading frame, overlapping with the region encoding the 20 amino acid repeats (20R) that are beta-catenin-binding sites. Each mutation in the MCR leads to the synthesis of a truncated APC product expressed in a colorectal tumour. The MCR extends from the 3' border of the first 20R coding region to approximately the middle of the third 20R coding region, reflecting both positive and negative selections of the N- and C-terminal halves of the APC protein in colon cancer cells, respectively. In contrast, the second 20R escapes selection and can be either included or excluded from the truncated APC products found in colon cancer cells. To specify the functional outcome of the selection of the mutations, we investigated the beta-catenin binding capacity of the first three 20R in N-terminal APC fragments. We found in co-immunoprecipitation and intracellular co-localization experiments that the second 20R is lacking any beta-catenin binding activity. Similarly, we also show that the tumour-associated truncations abolish the interaction of beta-catenin with the third 20R. Thus, our data provide a functional definition of the MCR: the APC fragments typical of colon cancer are selected for the presence of a single functional 20R, the first one, and are therefore equivalent relative to beta-catenin binding.

  5. DNA repair and crossing over favor similar chromosome regions as discovered in radiation hybrid of Triticum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The uneven distribution of recombination across the length of chromosomes results in inaccurate estimates of genetic to physical distances. In wheat (Triticum aestivum L.) chromosome 3B, it has been estimated that 90% of the cross over occurs in distal sub-telomeric regions representing 40% of the...

  6. Measurements of absolute absorption cross sections of ozone in the 185- to 254-nm wavelength region and the temperature dependence

    NASA Technical Reports Server (NTRS)

    Yoshino, K.; Esmond, J. R.; Freeman, D. E.; Parkinson, W. H.

    1993-01-01

    Laboratory measurements of the relative absorption cross sections of ozone at temperatures 195, 228, and 295 K have been made throughout the 185 to 254 nm wavelength region. The absolute absorption cross sections at the same temperatures have been measured at several discrete wavelengths in the 185 to 250 nm region. The absolute cross sections of ozone have been used to put the relative cross sections on a firm absolute basis throughout the 185 to 255 nm region. These recalibrated cross sections are slightly lower than those of Molina and Molina (1986), but the differences are within a few percent and would not be significant in atmospheric applications.

  7. High time resolution observations of HF cross-modulation within the D region ionosphere

    NASA Astrophysics Data System (ADS)

    Langston, J.; Moore, R. C.

    2013-05-01

    High-frequency cross-modulation is employed to probe the D region ionosphere during HF heating experiments at the High-frequency Active Auroral Research Program (HAARP) observatory. We have adapted Fejer's well-known cross-modulation probing method to determine the extent of ionospheric conductivity modification in the D region ionosphere with high (5 μsec) time resolution. We demonstrate that the method can be used to analyze D region conductivity changes produced by HF heating both during the initial stages of heating and under steady state conditions. The sequence of CW probe pulses used allow the separation of cross-modulation effects that occur as the probe pulse propagates upward and downward through the heated region. We discuss how this probing technique can be applied to benefit ELF/VLF wave generation experiments and ionospheric irregularities experiments at higher altitudes. We demonstrate that large phase changes equivalent to Doppler shift velocities >60 km/s can be imposed on HF waves propagating through the heated D region ionosphere.

  8. Photometric and Spectroscopic Survey of the Cluster [DBS2003] 156 Associated with the H II Region G331.1-0.5

    NASA Astrophysics Data System (ADS)

    Pinheiro, M. C.; Ortiz, R.; Abraham, Z.; Copetti, M. V. F.

    2016-05-01

    The Norma section of the Milky Way is especially interesting because it crosses three spiral arms: Sagittarius-Carina, Scutum-Crux and the Norma arm itself. Distance determinations of embedded young stellar clusters can contribute to define the spiral structure in this part of the Galaxy. However, spectrophotometric distances were obtained for only a few of these clusters in Norma. We present a photometric and spectroscopic study in the NIR of the [DBS2003] 156 stellar cluster, associated with the H II region G331.1-0.5. We aim to find the ionizing sources of the H II region and determine its distance. The cluster was observed in the J, H, and {K}{{s}} bands and eight potential massive stars were chosen among the detected sources according to color criteria; subsequent spectroscopy of these candidates was performed with the Ohio State Infrared Imager/Spectrometer spectrograph attached to the Southern Observatory for Astrophysical Research 4.1 m telescope. We identified and classified spectroscopically four early-type stars: IRS 176 (O8 V), IRS 308 (O-type), IRS 310 (O6 V), and IRS 71 (B1 Iab). Based on the proximity of IRS 176 and 308 with the radio continuum emission peaks and their relative positions with respect to the warm dust mid-infrared emission, we concluded that these two stars are the main ionizing sources of the H ii region G331.1-0.5. The mean spectrophotometric distance of IRS 176 and 310 of 3.38 ± 0.58 kpc is similar to that obtained in a previous work for two early-type stars of the neighbor cluster [DBS2003] 157 of 3.29 ± 0.58 kpc. The narrow range of radial velocities of radio sources in the area of the clusters [DBS2003] 156 and 157 and their similar visual extinction indicate that these clusters are physically associated. A common distance of 3.34 ± 0.34 kpc is derived for the system [DBS2003] 156 and 157. Based on observations obtained at the Southern Observatory for Astrophysical Research (SOAR), a joint project of the Ministério de Ci

  9. Multi-spacecraft studies of the auroral acceleration region: From cluster to nanosatellites

    NASA Astrophysics Data System (ADS)

    Sadeghi, S.; Emami, M. R.

    2017-03-01

    This paper discusses the utilization of multiple Cubesats in various formations for studies in the auroral acceleration region. The focus is on the quasi-static properties, spatio-temporal features, electric potential structures, field-aligned currents, and their relationships, all of which are fundamentally important for an understanding of the magnetosphere-ionosphere coupling. It is argued that a multitude of nanosatellites can address some of the relevant outstanding questions in a broader range of spatial, temporal, and geometrical features, with higher redundancy and data consistency, potentially resulting in a shorter mission period and a higher chance of mission success. A number of mission concepts consisting of a cluster of 6-12 Cubesats with their specific onboard payloads are suggested for such missions over a period of as short as two months.

  10. Coronal Mass Ejections from the Same Active Region Cluster: Two Different Perspectives

    NASA Astrophysics Data System (ADS)

    Cremades, H.; Mandrini, C. H.; Schmieder, B.; Crescitelli, A. M.

    2015-06-01

    The cluster formed by active regions (ARs) NOAA 11121 and 11123, approximately located on the solar central meridian on 11 November 2010, is of great scientific interest. This complex was the site of violent flux emergence and the source of a series of Earth-directed events on the same day. The onset of the events was nearly simultaneously observed by the Atmospheric Imaging Assembly (AIA) telescope onboard the Solar Dynamics Observatory (SDO) and the Extreme-Ultraviolet Imagers (EUVI) on the Sun-Earth Connection Coronal and Heliospheric Investigation (SECCHI) suite of telescopes onboard the Solar-Terrestrial Relations Observatory (STEREO) twin spacecraft. The progression of these events in the low corona was tracked by the Large Angle Spectroscopic Coronagraphs (LASCO) onboard the Solar and Heliospheric Observatory (SOHO) and the SECCHI/COR coronagraphs on STEREO. SDO and SOHO imagers provided data from the Earth's perspective, whilst the STEREO twin instruments procured images from the orthogonal directions. This spatial configuration of spacecraft allowed optimum simultaneous observations of the AR cluster and the coronal mass ejections that originated in it. Quadrature coronal observations provided by STEREO revealed many more ejective events than were detected from Earth. Furthermore, joint observations by SDO/AIA and STEREO/SECCHI EUVI of the source region indicate that all events classified by GOES as X-ray flares had an ejective coronal counterpart in quadrature observations. These results directly affect current space weather forecasting because alarms might be missed when there is a lack of solar observations in a view direction perpendicular to the Sun-Earth line.

  11. The collision cross sections of iodide salt cluster ions in air via differential mobility analysis-mass spectrometry.

    PubMed

    Ouyang, Hui; Larriba-Andaluz, Carlos; Oberreit, Derek R; Hogan, Christopher J

    2013-12-01

    To date, most collision cross section (CCS) predictions have invoked gas molecule impingement-reemission rules in which specular and elastic scattering of spherical gas molecules from rigid polyatomic surfaces are assumed. Although such predictions have been shown to agree well with CCSs measured in helium bath gas, a number of studies reveal that these predictions do not agree with CCSs for ions in diatomic gases, namely, air and molecular nitrogen. To further examine the validity of specular-elastic versus diffuse-inelastic scattering models, we measured the CCSs of positively charged metal iodide cluster ions of the form [MI]n[M(+)]z, where M = Na, K, Rb, or Cs, n = 1 - 25, and z = 1 - 2. Measurements were made in air via differential mobility analysis mass spectrometry (DMA-MS). The CCSs measured are compared with specular-elastic as well as diffuse-inelastic scattering model predictions with candidate ion structures determined from density functional theory. It is found that predictions from diffuse-inelastic collision models agree well (within 5%) with measurements from sodium iodide cluster ions, while specular-elastic collision model predictions are in better agreement with cesium iodide cluster ion measurements. The agreement with diffuse-inelastic and specular-elastic predictions decreases and increases, respectively, with increasing cation mass. However, even when diffuse-inelastic cluster ion predictions disagree with measurements, the disagreement is of a near-constant factor for all ions, indicating that a simple linear rescaling collapses predictions to measurements. Conversely, rescaling cannot be used to collapse specular-elastic predictions to measurements; hence, although the precise impingement reemission rules remain ambiguous, they are not specular-elastic.

  12. The Collision Cross Sections of Iodide Salt Cluster Ions in Air via Differential Mobility Analysis-Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Ouyang, Hui; Larriba-Andaluz, Carlos; Oberreit, Derek R.; Hogan, Christopher J.

    2013-12-01

    To date, most collision cross section (CCS) predictions have invoked gas molecule impingement-reemission rules in which specular and elastic scattering of spherical gas molecules from rigid polyatomic surfaces are assumed. Although such predictions have been shown to agree well with CCSs measured in helium bath gas, a number of studies reveal that these predictions do not agree with CCSs for ions in diatomic gases, namely, air and molecular nitrogen. To further examine the validity of specular-elastic versus diffuse-inelastic scattering models, we measured the CCSs of positively charged metal iodide cluster ions of the form [MI]n[M+]z, where M = Na, K, Rb, or Cs, n = 1 - 25, and z = 1 - 2. Measurements were made in air via differential mobility analysis mass spectrometry (DMA-MS). The CCSs measured are compared with specular-elastic as well as diffuse-inelastic scattering model predictions with candidate ion structures determined from density functional theory. It is found that predictions from diffuse-inelastic collision models agree well (within 5 %) with measurements from sodium iodide cluster ions, while specular-elastic collision model predictions are in better agreement with cesium iodide cluster ion measurements. The agreement with diffuse-inelastic and specular-elastic predictions decreases and increases, respectively, with increasing cation mass. However, even when diffuse-inelastic cluster ion predictions disagree with measurements, the disagreement is of a near-constant factor for all ions, indicating that a simple linear rescaling collapses predictions to measurements. Conversely, rescaling cannot be used to collapse specular-elastic predictions to measurements; hence, although the precise impingement reemission rules remain ambiguous, they are not specular-elastic.

  13. Regional structural cross sections, mid-permian to quaternary strata, Texas Panhandle and Eastern New Mexico

    SciTech Connect

    McGookey, D.A.; Gustavson, T.C.; Hoadley, A.D.

    1989-01-01

    Twelve regional cross sections (with text) of the Palo Duro, Dalhart, and Anadarko Basins illustrating the tabular geometry of Permian evaporite beds, areas where salt has been lost by dissolution, and the effects of dissolution-induced subsidence on Permian and post-Permian strata. The authors identify areas of dissolution beneath the High Plains, the Caprock Escarpment, the Rolling Plains, the Pecos Plains, and along the Canadian River valley. The cross sections are printed at a vertical scale of 1 inch equals 400 feet and a horizontal scale of 1 inch equals approximately 8 miles and were constructed using geophysical logs, sample logs, and surficial geologic data.

  14. Double diffractive cross-section measurement in the forward region at the LHC.

    PubMed

    Antchev, G; Aspell, P; Atanassov, I; Avati, V; Baechler, J; Berardi, V; Berretti, M; Bossini, E; Bottigli, U; Bozzo, M; Brücken, E; Buzzo, A; Cafagna, F S; Catanesi, M G; Covault, C; Csanád, M; Csörgő, T; Deile, M; Eggert, K; Eremin, V; Ferro, F; Fiergolski, A; Garcia, F; Giani, S; Greco, V; Grzanka, L; Heino, J; Hilden, T; Karev, A; Kašpar, J; Kopal, J; Kundrát, V; Kurvinen, K; Lami, S; Latino, G; Lauhakangas, R; Leszko, T; Lippmaa, E; Lippmaa, J; Lokajíček, M; Losurdo, L; Lo Vetere, M; Lucas Rodríguez, F; Macrí, M; Mäki, T; Mercadante, A; Minafra, N; Minutoli, S; Nemes, F; Niewiadomski, H; Oliveri, E; Oljemark, F; Orava, R; Oriunno, M; Österberg, K; Palazzi, P; Procházka, J; Quinto, M; Radermacher, E; Radicioni, E; Ravotti, F; Robutti, E; Ropelewski, L; Ruggiero, G; Saarikko, H; Scribano, A; Smajek, J; Snoeys, W; Sziklai, J; Taylor, C; Turini, N; Vacek, V; Vítek, M; Welti, J; Whitmore, J; Wyszkowski, P

    2013-12-27

    The first double diffractive cross-section measurement in the very forward region has been carried out by the TOTEM experiment at the LHC with a center-of-mass energy of sqrt[s]=7  TeV. By utilizing the very forward TOTEM tracking detectors T1 and T2, which extend up to |η|=6.5, a clean sample of double diffractive pp events was extracted. From these events, we determined the cross section σDD=(116±25)  μb for events where both diffractive systems have 4.7<|η|min<6.5.

  15. Career Indecision: Cross Cultural Differences in a Cluster Analysis among Two Groups of Undergraduate Students.

    ERIC Educational Resources Information Center

    Arce, Elsa M.

    A study determined differences among the levels and types of career indecision within and between two cross-cultural groups of undergraduate students from two counseling centers. The groups were 88 University of Pittsburgh students and 79 Universidad del Pacifico, Peru, students. The Indecision Scale of the Career Decision Scale (CDS) was used to…

  16. Interhemispheric currents in the ring current region as seen by the Cluster spacecraft

    NASA Astrophysics Data System (ADS)

    Tenfjord, P.; Ostgaard, N.; Haaland, S.; Laundal, K.; Reistad, J. P.

    2013-12-01

    The existence of interhemispheric currents has been predicted by several authors, but their extent in the ring current has to our knowledge never been studied systematically by using in-situ measurements. These currents have been suggested to be associated with observed asymmetries of the aurora. We perform a statistical study of current density and direction during ring current crossings using the Cluster spacecraft. We analyse the extent of the interhemispheric field aligned currents for a wide range of solar wind conditions. Direct estimations of equatorial current direction and density are achieved through the curlometer technique. The curlometer technique is based on Ampere's law and requires magnetic field measurements from all four spacecrafts. The use of this method requires careful study of factors that limit the accuracy, such as tetrahedron shape and configuration. This significantly limits our dataset, but is a necessity for accurate current calculations. Our goal is to statistically investigate the occurrence of interhemispheric currents, and determine if there are parameters or magnetospheric states on which the current magnitude and directions depend upon.

  17. Clustered somatic mutations are frequent in transcription factor binding motifs within proximal promoter regions in melanoma and other cutaneous malignancies

    PubMed Central

    Colebatch, Andrew J.; Di Stefano, Leon; Wong, Stephen Q.; Hannan, Ross D.; Waring, Paul M.; Dobrovic, Alexander

    2016-01-01

    Most cancer DNA sequencing studies have prioritized recurrent non-synonymous coding mutations in order to identify novel cancer-related mutations. Although attention is increasingly being paid to mutations in non-coding regions, standard approaches to identifying significant mutations may not be appropriate and there has been limited analysis of mutational clusters in functionally annotated non-coding regions. We sought to identify clustered somatic mutations (hotspot regions across samples) in functionally annotated regions in melanoma and other cutaneous malignancies (cutaneous squamous cell carcinoma, basal cell carcinoma and Merkel cell carcinoma). Sliding window analyses revealed numerous recurrent clustered hotspot mutations in proximal promoters, with some specific clusters present in up to 25% of cases. Mutations in melanoma were clustered within ETS and Sp1 transcription factor binding motifs, had a UV signature and were identified in other cutaneous malignancies. Clinicopathologic correlation and mutation analysis support a causal role for chronic UV irradiation generating somatic mutations in transcription factor binding motifs of proximal promoters. PMID:27611953

  18. [Cross reactivity of mimotopes of hepatitis C virus hypervariable region 1].

    PubMed

    Yang, Miao; Zhao, Ping; Bian, Zhong-qi; Ren, Yan-li; Gong, Yu-ping; Qi, Zhong-tian

    2008-07-01

    The cross reactivity of mimotopes of hepatitis C virus (HCV) hypervariable region 1 (HVR1) was investigated to obtain epitopes that have high cross reactivity. Five expression vectors encoding B cell mimotopes fused with Trx were constructed, and the mimotope proteins were purified. The cross reactivity of mimotope proteins with HCV positive sera was determined by ELISA. HCV pseudotype particles (HCVpp) were generated and applied to evaluate neutralization effects of the sera of BALB/c mice immuned with the mimotope proteins on infection of Huh7. 5 cells. Our data showed that the mimotope proteins (P1, P2, P5, P6, P8) could react to the HCV positive sera. The HCVpp infection inhibition of the sera of BALB/c mice immuned with P6 or P8 was detectable. These results suggest that the mimotopes may be valuable in the studies of anti-HCV infection and development of HCV vaccines.

  19. Images in the rocket ultraviolet - Young clusters in H II regions of M83

    NASA Technical Reports Server (NTRS)

    Bohlin, Ralph C.; Cornett, Robert H.; Hill, Jesse K.; Stecher, Theodore P.

    1990-01-01

    UV images of M83 at 1540 and 2360 A reveal 18 compact sources that are associated with H II regions. E(B - V) values were estimated individually from the observed UV and optical colors and the Galactic UV extinction curve, using theoretical flux distributions. The dereddened colors are consistent with ages up to 3 x 10 to the 6th yr. A maximum possible age of 6.5 x 10 to the 6th yr is obtained assuming foreground reddening only. The distribution of observed colors is consistent with the Galactic reddening curve but not with enhanced far-UV extinction, as in the LMC 30 Dor curve. The H-alpha fluxes suggest either that dust within the H II regions absorbs up to 70 percent of the Lyman continuum radiation or that a similar fraction of the H-alpha flux is below the surface brightness detection limit. Cluster mass estimates depend on the range of stellar masses present but are probably in the range 10,000-100,000 solar masses.

  20. High Resolution Spectra of Carbon Dioxide Clusters in the νb{3} Band Region

    NASA Astrophysics Data System (ADS)

    McKellar, A. R. W.; Afshari, Mahin; Dehghany, M.; Moazzen-Ahmadi, N.

    2010-06-01

    There is widespread interest in carbon dioxide clusters from a variety of experimental and theoretical perspectives. But in terms of high resolution spectroscopy, the only definitive information concerns (CO_2)_2 and (CO_2)_3. The dimer has a planar slipped parallel geometry with C2h symmetry. Two isomers are known for the trimer: a planar cyclic form with C3h symmetry and a sort of "barrel-shaped" form with C_2 symmetry. Here we analyze two new bands in the CO_2 νb{3} region. The first is a dimer combination band near 2382 wn whose assignment raises interesting questions about the intermolecular vibrations of (CO_2)_2. The second band is a trimer band near 2370 wn which is very similar to one we observed previously near 2364 wn. We assign it to a combination involving another out-of-plane vibration of the cyclic trimer. In addition to these newly assigned bands, we also discuss a number of clear and (mostly) well-resolved bands which apparently must belong to (CO_2)_N clusters with N in the range 6 ˜ 15. Although they cannot be precisely assigned at this time, these bands offer intriguing future prospects for learning more about the structures and vibrational dynamics of CO_2 clusters in a challenging and important size range. K.W. Jucks, Z.S. Huang, D. Dayton, R.E. Miller, and W.J. Lafferty, J. Chem. Phys. 86, 4341 (1987); M.A. Walsh, T.H. England, T.R. Dyke, and B.J. Howard, Chem. Phys. Lett. 142, 265 (1987). G.T. Fraser, A.S. Pine, W.J. Lafferty and R.E. Miller, J. Chem. Phys. 87, 1502 (1987). M.J. Weida and D.J. Nesbitt, J. Chem. Phys. 105, 10210 (1996). H. Chen and J.C. Light, J. Chem. Phys. 112, 5070 (2000). M. Dehghany, M. Afshari, N. Moazzen-Ahmadi, and A.R.W. McKellar, J. Chem. Phys. 128, 064308 (2008).

  1. Cross-modal activation of auditory regions during visuo-spatial working memory in early deafness.

    PubMed

    Ding, Hao; Qin, Wen; Liang, Meng; Ming, Dong; Wan, Baikun; Li, Qiang; Yu, Chunshui

    2015-09-01

    Early deafness can reshape deprived auditory regions to enable the processing of signals from the remaining intact sensory modalities. Cross-modal activation has been observed in auditory regions during non-auditory tasks in early deaf subjects. In hearing subjects, visual working memory can evoke activation of the visual cortex, which further contributes to behavioural performance. In early deaf subjects, however, whether and how auditory regions participate in visual working memory remains unclear. We hypothesized that auditory regions may be involved in visual working memory processing and activation of auditory regions may contribute to the superior behavioural performance of early deaf subjects. In this study, 41 early deaf subjects (22 females and 19 males, age range: 20-26 years, age of onset of deafness < 2 years) and 40 age- and gender-matched hearing controls underwent functional magnetic resonance imaging during a visuo-spatial delayed recognition task that consisted of encoding, maintenance and recognition stages. The early deaf subjects exhibited faster reaction times on the spatial working memory task than did the hearing controls. Compared with hearing controls, deaf subjects exhibited increased activation in the superior temporal gyrus bilaterally during the recognition stage. This increased activation amplitude predicted faster and more accurate working memory performance in deaf subjects. Deaf subjects also had increased activation in the superior temporal gyrus bilaterally during the maintenance stage and in the right superior temporal gyrus during the encoding stage. These increased activation amplitude also predicted faster reaction times on the spatial working memory task in deaf subjects. These findings suggest that cross-modal plasticity occurs in auditory association areas in early deaf subjects. These areas are involved in visuo-spatial working memory. Furthermore, amplitudes of cross-modal activation during the maintenance stage were

  2. Imaging active faulting in a region of distributed deformation from the joint clustering of focal mechanisms and hypocentres: Application to the Azores-western Mediterranean region

    NASA Astrophysics Data System (ADS)

    Custódio, Susana; Lima, Vânia; Vales, Dina; Cesca, Simone; Carrilho, Fernando

    2016-04-01

    The matching between linear trends of hypocentres and fault planes indicated by focal mechanisms (FMs) is frequently used to infer the location and geometry of active faults. This practice works well in regions of fast lithospheric deformation, where earthquake patterns are clear and major structures accommodate the bulk of deformation, but typically fails in regions of slow and distributed deformation. We present a new joint FM and hypocentre cluster algorithm that is able to detect systematically the consistency between hypocentre lineations and FMs, even in regions of distributed deformation. We apply the method to the Azores-western Mediterranean region, with particular emphasis on western Iberia. The analysis relies on a compilation of hypocentres and FMs taken from regional and global earthquake catalogues, academic theses and technical reports, complemented by new FMs for western Iberia. The joint clustering algorithm images both well-known and new seismo-tectonic features. The Azores triple junction is characterised by FMs with vertical pressure (P) axes, in good agreement with the divergent setting, and the Iberian domain is characterised by NW-SE oriented P axes, indicating a response of the lithosphere to the ongoing oblique convergence between Nubia and Eurasia. Several earthquakes remain unclustered in the western Mediterranean domain, which may indicate a response to local stresses. The major regions of consistent faulting that we identify are the mid-Atlantic ridge, the Terceira rift, the Trans-Alboran shear zone and the north coast of Algeria. In addition, other smaller earthquake clusters present a good match between epicentre lineations and FM fault planes. These clusters may signal single active faults or wide zones of distributed but consistent faulting. Mainland Portugal is dominated by strike-slip earthquakes with fault planes coincident with the predominant NNE-SSW and WNW-ESE oriented earthquake lineations. Clusters offshore SW Iberia are

  3. Regional incentives and patient cross-border mobility: evidence from the Italian experience

    PubMed Central

    Brenna, Elenka; Spandonaro, Federico

    2015-01-01

    Background: In recent years, accreditation of private hospitals followed by decentralisation of the Italian National Health Service (NHS) into 21 regional health systems has provided a good empirical ground for investigating the Tiebout principle of "voting with their feet". We examine the infra-regional trade-off between greater patient choice (due to an increase in hospital services supply) and financial equilibrium, and we relate it to the significant phenomenon of Cross-Border Mobility (CBM) between Italian regions. Focusing on the rules supervising the financial agreements between regional authorities and providers of hospital care, we find incentives for private accredited providers in attracting patient inflows. Methods: The analysis is undertaken from an institutional, regulatory and empirical perspective. We select a sample of five regions with higher positive CBM balance and we examine regional regulations governing the contractual agreements between purchasers and providers of hospital care. According to this sample, we provide a statistical analysis of CBM and apply a Regional Attraction Ability Index (RAAI), aimed at testing patient preferences for private/public accredited providers. Results: We find that this index is systematically higher for private providers, both in the case of distance/boundary patients and of excellence/general hospitals. Conclusion: Conclusions address both financial issues regarding the coverage of regional healthcare systems and equity issues on patient healthcare access. They also raise concerns on the new European Union (EU) directive inherent to patient mobility across Europe. PMID:26029895

  4. Regionalizing aquatic ecosystems based on the river subbasin taxonomy concept and spatial clustering techniques.

    PubMed

    Gao, Yongnian; Gao, Junfeng; Chen, Jiongfeng; Xu, Yan; Zhao, Jiahu

    2011-11-01

    Aquatic ecoregions were increasingly used as spatial units for aquatic ecosystem management at the watershed scale. In this paper, the principle of including land area, comprehensiveness and dominance, conjugation and hierarchy were selected as regionalizing principles. Elevation and drainage density were selected as the regionalizing indicators for the delineation of level I aquatic ecoregions, and percent of construction land area, percent of cultivated land area, soil type and slope for the level II. Under the support of GIS technology, the spatial distribution maps of the two indicators for level I and the four indicators for level II aquatic ecoregion delineation were generated from the raster data based on the 1,107 subwatersheds. River subbasin taxonomy concept, two-step spatial clustering analysis approach and manual-assisted method were used to regionalize aquatic ecosystems in the Taihu Lake watershed. Then the Taihu Lake watershed was divided into two level I aquatic ecoregions, including Ecoregion I1 and Ecoregion I2, and five level II aquatic subecoregions, including Subecoregion II11, Subecoregion II12, Subecoregion II21, Subecoregion II22 and Subecoregion II23. Moreover, the characteristics of the two level I aquatic ecoregions and five level II aquatic subecoregions in the Taihu Lake watershed were summarized, showing that there were significant differences in topography, socio-economic development, water quality and aquatic ecology, etc. The results of quantitative comparison of aquatic life also indicated that the dominant species of fish, benthic density, biomass, dominant species, Shannon-Wiener diversity index, Margalef species richness index, Pielou evenness index and ecological dominance showed great spatial variability between the two level I aquatic ecoregions and five level II aquatic subecoregions. It reflected the spatial heterogeneities and the uneven natures of aquatic ecosystems in the Taihu Lake watershed.

  5. Analysis of Hydrogen Bonding in the OH Stretch Region of Protonated Water Clusters

    NASA Astrophysics Data System (ADS)

    Dzugan, Laura C.; McCoy, Anne B.

    2015-06-01

    There are two types of bands in the OH stretch region of the vibrational spectra of hydrogen-bonded complexes; narrow peaks due to isolated OH stretches and a broadened feature reflecting the OH stretches involved in strong hydrogen bonding. This second region can be as wide as several hundred wavenumbers and is shifted to the red of the narrow peaks. In this work we focus on H+(H2O)n, where n = 3 or 4. Both of these systems exhibit a very intense, broad H-bonded band. This breadth arises from coupling between the OH stretches and the low frequency modes. To understand the broadening observed in the spectra, we have developed a computational scheme in which we sample displacement geometries from the equilibrium structure based on the ground state harmonic wavefunction. Then we combine the harmonic spectra in the OH stretch region for each computed geometry to generate the spectrum for each protonated water structure. Based on the large anharmonicities at play in these modes, we extend the approach using second-order perturbation theory to solve the reduced-dimensional Hamiltonian that involves only the HOH bends and the OH stretches. This is done by expressing the normal modes used to expand the Hamiltonian as linear combinations of internal coordinates. In this talk we will describe the approach used for these anharmonic calculations and report preliminary results for these protonated water clusters. Relph, R. A.; Guasco, T. L.; Elliot, B. M.; Kamrath, M. Z.; McCoy, A. B.; Steele, R. P.; Schofield, D. P.; Jordan, K. D.; Viggiano, A. A.; Ferguson, E. E.; Johnson, M. A. Science, 2010, 327(5963), 308-312. Johnson, C. J.; Dzugan, L. C.; Wolk, A. B.; Leavitt, C. M.; Fournier, J. A.; McCoy, A. B.; Johnson, M. A. J. Phys. Chem. A, 2014, 118, 7590-7597.

  6. A Cross-Sectional, Randomized Cluster Sample Survey of Household Vulnerability to Extreme Heat among Slum Dwellers in Ahmedabad, India

    PubMed Central

    Tran, Kathy V.; Azhar, Gulrez S.; Nair, Rajesh; Knowlton, Kim; Jaiswal, Anjali; Sheffield, Perry; Mavalankar, Dileep; Hess, Jeremy

    2013-01-01

    Extreme heat is a significant public health concern in India; extreme heat hazards are projected to increase in frequency and severity with climate change. Few of the factors driving population heat vulnerability are documented, though poverty is a presumed risk factor. To facilitate public health preparedness, an assessment of factors affecting vulnerability among slum dwellers was conducted in summer 2011 in Ahmedabad, Gujarat, India. Indicators of heat exposure, susceptibility to heat illness, and adaptive capacity, all of which feed into heat vulnerability, was assessed through a cross-sectional household survey using randomized multistage cluster sampling. Associations between heat-related morbidity and vulnerability factors were identified using multivariate logistic regression with generalized estimating equations to account for clustering effects. Age, preexisting medical conditions, work location, and access to health information and resources were associated with self-reported heat illness. Several of these variables were unique to this study. As sociodemographics, occupational heat exposure, and access to resources were shown to increase vulnerability, future interventions (e.g., health education) might target specific populations among Ahmedabad urban slum dwellers to reduce vulnerability to extreme heat. Surveillance and evaluations of future interventions may also be worthwhile. PMID:23778061

  7. A cross-sectional, randomized cluster sample survey of household vulnerability to extreme heat among slum dwellers in ahmedabad, india.

    PubMed

    Tran, Kathy V; Azhar, Gulrez S; Nair, Rajesh; Knowlton, Kim; Jaiswal, Anjali; Sheffield, Perry; Mavalankar, Dileep; Hess, Jeremy

    2013-06-18

    Extreme heat is a significant public health concern in India; extreme heat hazards are projected to increase in frequency and severity with climate change. Few of the factors driving population heat vulnerability are documented, though poverty is a presumed risk factor. To facilitate public health preparedness, an assessment of factors affecting vulnerability among slum dwellers was conducted in summer 2011 in Ahmedabad, Gujarat, India. Indicators of heat exposure, susceptibility to heat illness, and adaptive capacity, all of which feed into heat vulnerability, was assessed through a cross-sectional household survey using randomized multistage cluster sampling. Associations between heat-related morbidity and vulnerability factors were identified using multivariate logistic regression with generalized estimating equations to account for clustering effects. Age, preexisting medical conditions, work location, and access to health information and resources were associated with self-reported heat illness. Several of these variables were unique to this study. As sociodemographics, occupational heat exposure, and access to resources were shown to increase vulnerability, future interventions (e.g., health education) might target specific populations among Ahmedabad urban slum dwellers to reduce vulnerability to extreme heat. Surveillance and evaluations of future interventions may also be worthwhile.

  8. Evidence that Plasmodium falciparum chromosome end clusters are cross-linked by protein and are the sites of both virulence gene silencing and activation.

    PubMed

    Marty, Allison J; Thompson, Jennifer K; Duffy, Michael F; Voss, Till S; Cowman, Alan F; Crabb, Brendan S

    2006-10-01

    The malaria parasite Plasmodium falciparum undergoes antigenic variation through allelic exclusion and variant expression of surface proteins encoded by the var gene family. Regulation of var genes is under epigenetic control and involves reversible silencing and activation that requires the physical repositioning of a var locus into a transcriptionally permissive zone of the nuclear periphery. P. falciparum chromosome ends appear to aggregate into large perinuclear clusters which house both subtelomeric and chromosome central var genes. In this study we further define the composition of telomeric clusters using fluorescent in situ hybridization, and provide evidence that chromosome end clusters are formed by cross-linking protein. In addition, we demonstrate that a subtelomeric reporter gene and a var gene remain within clusters regardless of their transcriptional status. Our findings support a model whereby a highly localized structure dedicated to the activation of a single var gene can be housed within a gene dense chromosome end cluster that is otherwise transcriptionally silent.

  9. User’s guide for GcClust—An R package for clustering of regional geochemical data

    USGS Publications Warehouse

    Ellefsen, Karl J.; Smith, David B.

    2016-04-08

    GcClust is a software package developed by the U.S. Geological Survey for statistical clustering of regional geochemical data, and similar data such as regional mineralogical data. Functions within the software package are written in the R statistical programming language. These functions, their documentation, and a copy of the user’s guide are bundled together in R’s unit of sharable code, which is called a “package.” The user’s guide includes step-by-step instructions showing how the functions are used to cluster data and to evaluate the clustering results. These functions are demonstrated in this report using test data, which are included in the package.

  10. NEUTRON CROSS SECTION EVALUATIONS OF FISSION PRODUCTS BELOW THE FAST ENERGY REGION

    SciTech Connect

    OH,S.Y.; CHANG,J.; MUGHABGHAB,S.

    2000-05-11

    Neutron cross section evaluations of the fission-product isotopes, {sup 95}Mo, {sup 99}Tc, {sup 101}Ru, {sup 103}Rh, {sup 105}Pd, {sup 109}Ag, {sup 131}Xe, {sup 133}Cs, {sup 141}Pr, {sup 141}Nd, {sup 147}Sm, {sup 149}Sm, {sup 150}Sm, {sup 151}Sm, {sup 152}Sm, {sup 153}Eu, {sup 155}Gd, and {sup 157}Gd were carried out below the fast neutron energy region within the framework of the BNL-KAERI international collaboration. In the thermal energy region, the energy dependence of the various cross-sections was calculated by applying the multi-level Breit-Wigner formalism. In particular, the strong energy dependence of the coherent scattering lengths of {sup 155}Gd and {sup 157}Gd were determined and were compared with recent calculations of Lynn and Seeger. In the resonance region, the recommended resonance parameters, reported in the BNL compilation, were updated by considering resonance parameter information published in the literature since 1981. The s-wave and, if available, p-wave reduced neutron widths were analyzed in terms of the Porter-Thomas distribution to determine the average level spacings and the neutron strength functions. Average radiative widths were also calculated from measured values of resolved energy resonances. The average resonance parameters determined in this study were compared with those in the BNL and other compilations, as well as the ENDF/B-VI, JEF-2.2, and JENDL-3.2 data libraries. The unresolved capture cross sections of these isotopes, computed with the determined average resonance parameters, were compared with measurements, as well as the ENDF/B-VI evaluations. To achieve agreement with the measurements, in a few cases minor adjustments in the average resonance parameters were made. Because of astrophysical interest, the Maxwellian capture cross sections of these nuclides at a neutron temperature of 30 keV were computed and were compared with other compilations and evaluations.

  11. Mutations in the ligand-binding domain of the androgen receptor gene cluster in two regions of the gene.

    PubMed

    McPhaul, M J; Marcelli, M; Zoppi, S; Wilson, C M; Griffin, J E; Wilson, J D

    1992-11-01

    We have analyzed the nucleotide sequence of the androgen receptor from 22 unrelated subjects with substitution mutations of the hormone-binding domain. Eleven had the phenotype of complete testicular feminization, four had incomplete testicular feminization, and seven had Reifenstein syndrome. The underlying functional defect in cultured skin fibroblasts included individuals with absent, qualitative, or quantitative defects in ligand binding. 19 of the 21 substitution mutations (90%) cluster in two regions that account for approximately 35% of the hormone-binding domain, namely, between amino acids 726 and 772 and between amino acids 826 and 864. The fact that one of these regions is homologous to a region of the human thyroid hormone receptor (hTR-beta) which is a known cluster site for mutations that cause thyroid hormone resistance implies that this localization of mutations is not a coincidence. These regions of the androgen receptor may be of particular importance for the formation and function of the hormone-receptor complex.

  12. SERA Scenarios of Early Market Fuel Cell Electric Vehicle Introductions: Modeling Framework, Regional Markets, and Station Clustering

    SciTech Connect

    Bush, B.; Melaina, M.; Penev, M.; Daniel, W.

    2013-09-01

    This report describes the development and analysis of detailed temporal and spatial scenarios for early market hydrogen fueling infrastructure clustering and fuel cell electric vehicle rollout using the Scenario Evaluation, Regionalization and Analysis (SERA) model. The report provides an overview of the SERA scenario development framework and discusses the approach used to develop the nationwidescenario.

  13. Prospects for Formation and Development of the Geographical (Territorial) Industrial Clusters in West Kazakhstan Region of the Republic of Kazakhstan

    ERIC Educational Resources Information Center

    Imashev, Eduard Zh.

    2016-01-01

    The purpose of this research is to develop and implement an economic and geographic approach to forming and developing geographic (territorial) industrial clusters in regions of Kazakhstan. The purpose necessitates the accomplishment of the following scientific objectives: to investigate scientific approaches and experience of territorial economic…

  14. Cross-scale Efficient Tensor Contractions for Coupled Cluster Computations Through Multiple Programming Model Backends

    SciTech Connect

    Ibrahim, Khaled Z.; Epifanovsky, Evgeny; Williams, Samuel W.; Krylov, Anna I.

    2016-07-26

    Coupled-cluster methods provide highly accurate models of molecular structure by explicit numerical calculation of tensors representing the correlation between electrons. These calculations are dominated by a sequence of tensor contractions, motivating the development of numerical libraries for such operations. While based on matrix-matrix multiplication, these libraries are specialized to exploit symmetries in the molecular structure and in electronic interactions, and thus reduce the size of the tensor representation and the complexity of contractions. The resulting algorithms are irregular and their parallelization has been previously achieved via the use of dynamic scheduling or specialized data decompositions. We introduce our efforts to extend the Libtensor framework to work in the distributed memory environment in a scalable and energy efficient manner. We achieve up to 240 speedup compared with the best optimized shared memory implementation. We attain scalability to hundreds of thousands of compute cores on three distributed-memory architectures, (Cray XC30&XC40, BlueGene/Q), and on a heterogeneous GPU-CPU system (Cray XK7). As the bottlenecks shift from being compute-bound DGEMM's to communication-bound collectives as the size of the molecular system scales, we adopt two radically different parallelization approaches for handling load-imbalance. Nevertheless, we preserve a uni ed interface to both programming models to maintain the productivity of computational quantum chemists.

  15. Searching for Distant Galaxy Clusters: Utilizing the Virtual Observatory for Multiwavelength Images and Survey Cross-correlation

    NASA Astrophysics Data System (ADS)

    Van Duyne, J.; Lucas, R.; Tamura, T.; Rohde, D.

    2004-12-01

    Through the tools and technology made available via the Virtual Observatory, we have explored the multiwavelength properties, survey coverage, and environments of a sample of 71 steep (-1.0 < α < 0.5) spectrum radio sources taken from the Texas Interferometer Radio catalog (Douglas et al. 1996). Through the VLA proposal by Lucas & Chambers (1989), these radio sources were observed with the A-array configuration at 20 cm and 1485 MHz and with 1 full Schmidt SRC-J, high-latitude sky survey plate ( ˜ 6 sq deg) down to J ˜ 22 with the purpose of finding optical counterparts of mid-to-high z galaxy clusters. With the knowledge that this field had been imaged via the Sloan Digital Sky Survey (SDSS DR2, r=22.2), we submitted the coordinates of the Lucas & Chambers survey sources to the VO image access protocol (SIAP) to quickly and efficiently explore the SDSS ugriz 5-band color images of these sources, specifically looking for u-band drop-outs. Additionally, we used this same technique to explore the multiwavelength coverage of this field with all surveys registered with the VO (2MASS, ROSAT, VLA FIRST/NVSS, Chandra, XMM) via ˜ 1 arcminute snapshots. This revealed a multitude of interesting objects, such as double-lobed radio galaxies with bent jets, implying intercluster medium interactions, extremely faint optical sources with point source 2MASS/J-band detections, and the re-discovery of 3C 273. Finally, as a proof of concept, we utilized the VO tool Topcat to cross-correlate the radio and X-ray positions of known galaxy clusters via the RBSC-NVSS Sample (Bauer et al. 2000) and ROSAT Brightest Cluster Sample (Ebeling et al. 1998), resulting in 17 clusters matched at < 15 arcsec separation. These results demonstrate the simple, yet highly effective utility of the Virtual Observatory on a sample data set to reveal scientifically interesting objects on a short timescale. We would like to acknowledge the National Virtual Observatory Summer School for supplying the

  16. Huntingtin-Associated Protein 1 Interacts with Breakpoint Cluster Region Protein to Regulate Neuronal Differentiation

    PubMed Central

    Huang, Pai-Tsang; Chen, Chien-Ho; Hsu, I-Uen; Salim, Shaima’a Ahmad; Kao, Shu-Huei; Cheng, Chao-Wen; Lai, Chang-Hao; Lee, Cheng-Fan; Lin, Yung-Feng

    2015-01-01

    Alterations in microtubule-dependent trafficking and certain signaling pathways in neuronal cells represent critical pathogenesis in neurodegenerative diseases. Huntingtin (Htt)-associated protein-1 (Hap1) is a brain-enriched protein and plays a key role in the trafficking of neuronal surviving and differentiating cargos. Lack of Hap1 reduces signaling through tropomyosin-related kinases including extracellular signal regulated kinase (ERK), resulting in inhibition of neurite outgrowth, hypothalamic dysfunction and postnatal lethality in mice. To examine how Hap1 is involved in microtubule-dependent trafficking and neuronal differentiation, we performed a proteomic analysis using taxol-precipitated microtubules from Hap1-null and wild-type mouse brains. Breakpoint cluster region protein (Bcr), a Rho GTPase regulator, was identified as a Hap1-interacting partner. Bcr was co-immunoprecipitated with Hap1 from transfected neuro-2a cells and co-localized with Hap1A isoform more in the differentiated than in the nondifferentiated cells. The Bcr downstream effectors, namely ERK and p38, were significantly less activated in Hap1-null than in wild-type mouse hypothalamus. In conclusion, Hap1 interacts with Bcr on microtubules to regulate neuronal differentiation. PMID:25671650

  17. Low and room temperature photoabsorption cross sections of NH3 in the UV region

    NASA Astrophysics Data System (ADS)

    Chen, F. Z.; Judge, D. L.; Wu, C. Y. R.; Caldwell, J.

    1998-12-01

    Using synchrotron radiation as a continuum light source, we have measured the absolute absorption cross sections of NH3 with a spectral bandwidth (FWHM) of 0.5 Å. The photoabsorption cross sections of NH3 have been measured from 1750 to 2250 Å under temperature conditions of 295, 195, and 175 K. Significant temperature effects in the absorption threshold region which are mainly due to the presence of hot band absorption are observed. The cross section value at peaks and valleys for the vibrational progressions of the (0,0) to (4,0) bands vary between -80% and +40% as the temperature of NH3 changes from 295 to 175 K. In contrast to this, the changes of cross section values, Pc,T, are found to vary less than 20% for the (v', 0) vibrational progressions with v' >= 5. The measured separations between the doublet features of the (0,0), (1,0), and (2,0) bands are found to decrease as the temperature of NH3 decreases. The shifts of peak positions of Pc,T with respect to the corresponding room temperature absorption peaks show a sudden change at v' = 3 which appears to agree with the trend observed in the homogeneous line widths of the vibrational bands of NH3 ([Vaida et al., 1987]; [Ziegler, 1985]; [Ziegler, 1986]). The unusual behavior of the line widths has been attributed to the A~ state potential surface which has a dissociation barrier.

  18. Analysis of D-Region Absorption via HF Cross-Modulation Experiments at HAARP

    NASA Astrophysics Data System (ADS)

    Braun, E. M.; Moore, R. C.

    2010-12-01

    Experimental observations performed near the High-frequency Active Auroral Research Program (HAARP) HF transmitter in Gakona, Alaska are used to implement a new method quantifying the rate of absorption of HF radio waves in the D-region ionosphere. Quantifying the ambient and HF-modified characteristics of the D-region ionosphere in the vicinity of ionospheric HF heaters has historically proven to be a difficult task. For example, the electron density in the 60-90 km altitude range is typically too low to employ radio-sounding techniques; LIDAR observations typically require significant temporal averaging, precluding the investigation of physical processes that occur on sub-millisecond time scales; ELF/VLF wave generation experiments typically have difficulty providing reliable spatial resolution and also cannot experimentally distinguish between the spatial distribution of the ionospheric conductivity modulation produced by modulated HF heating and that of the current-driving electric fields associated with the auroral electrojet. Yet, the majority of HF signal absorption occurs in this region of the ionosphere, and the ability to characterize HF absorption in this region benefits a wide range of ionospheric HF heating experiments. The technique described and demonstrated in this paper combines ionosonde-style radio sounding with ELF/VLF cross-modulation experiments to identify the altitude of maximum D-region absorption as a function of HF frequency. Observations are presented and compared with the predictions of a theoretical model, demonstrating excellent agreement between experiment and theory and indicating that the technique may be used successfully in practice. Based on the success of this first experiment, another HF cross-modulation experiment has been performed at HAARP and analyzed theoretically. Pulsed-modulation experiments are used to assess the relative absorption as a function of altitude within the D-region ionosphere, and a method to chart the

  19. A Dozen New Galaxies Caught in the Act: Gas Stripping and Extended Emission Line Regions in the Coma Cluster

    NASA Astrophysics Data System (ADS)

    Yagi, Masafumi; Yoshida, Michitoshi; Komiyama, Yutaka; Kashikawa, Nobunari; Furusawa, Hisanori; Okamura, Sadanori; Graham, Alister W.; Miller, Neal A.; Carter, David; Mobasher, Bahram; Jogee, Shardha

    2010-12-01

    We present images of extended Hα clouds associated with 14 member galaxies in the Coma cluster obtained from deep narrowband imaging observations with the Suprime-Cam at the Subaru Telescope. The parent galaxies of the extended Hα clouds are distributed farther than 0.2 Mpc from the peak of the X-ray emission of the cluster. Most of the galaxies are bluer than g - r ≈ 0.5 and they account for 57% of the blue (g - r < 0.5) bright (r < 17.8 mag) galaxies in the central region of the Coma cluster. They reside near the red- and blueshifted edges of the radial velocity distribution of Coma cluster member galaxies. Our findings suggest that most of the parent galaxies were recently captured by the Coma cluster potential and are now infalling toward the cluster center with their disk gas being stripped off and producing the observed Hα clouds. Based on data collected at the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.

  20. Spatial inequalities in life expectancy within postindustrial regions of Europe: a cross-sectional observational study

    PubMed Central

    Taulbut, Martin; Walsh, David; McCartney, Gerry; Parcell, Sophie; Hartmann, Anja; Poirier, Gilles; Strniskova, Dana; Hanlon, Phil

    2014-01-01

    Objectives To compare spatial inequalities in life expectancy (LE) in West Central Scotland (WCS) with nine other postindustrial European regions. Design A cross-sectional observational study. Setting WCS and nine other postindustrial regions across Europe. Participants Data for WCS and nine other comparably deindustrialised European regions were analysed. Male and female LEs at birth were obtained or calculated for the mid-2000s for 160 districts within selected regions. Districts were stratified into two groups: small (populations of between 141 000 and 185 000 people) and large (populations between 224 000 and 352 000). The range and IQR in LE were used to describe within-region disparities. Results In small districts, the male LE range was widest in WCS and Merseyside, while the IQR was widest in WCS and Northern Ireland. For women, the LE range was widest in WCS, though the IQR was widest in Northern Ireland and Merseyside. In large districts, the range and IQR in LE was widest in WCS and Wallonia for both sexes. Conclusions Subregional spatial inequalities in LE in WCS are wide compared with other postindustrial mainland European regions, especially for men. Future research could explore the contribution of economic, social and political factors in reducing these inequalities. PMID:24889851

  1. Photoionization cross section measurements of the excited states of cobalt in the near-threshold region

    SciTech Connect

    Zheng, Xianfeng Zhou, Xiaoyu; Cheng, Zaiqi; Jia, Dandan; Qu, Zehua; Yao, Guanxin; Zhang, Xianyi; Cui, Zhifeng

    2014-10-15

    We present measurements of photoionization cross-sections of the excited states of cobalt using a two-color, two-step resonance ionization technique in conjunction with a molecular beam time of flight (TOF) mass spectrometer. The atoms were produced by the laser vaporization of a cobalt rod, coupled with a supersonic gas jet. The absolute photoionization cross-sections at threshold and near-threshold regions (0-1.2 eV) were measured, and the measured values ranged from 4.2±0.7 Mb to 10.5±1.8 Mb. The lifetimes of four odd parity energy levels are reported for the first time.

  2. Neutron capture cross section measurements for 238U in the resonance region at GELINA

    NASA Astrophysics Data System (ADS)

    Kim, H. I.; Paradela, C.; Sirakov, I.; Becker, B.; Capote, R.; Gunsing, F.; Kim, G. N.; Kopecky, S.; Lampoudis, C.; Lee, Y.-O.; Massarczyk, R.; Moens, A.; Moxon, M.; Pronyaev, V. G.; Schillebeeckx, P.; Wynants, R.

    2016-06-01

    Measurements were performed at the time-of-flight facility GELINA to determine the 238U(n, γ) cross section in the resonance region. Experiments were carried out at a 12.5 and 60m measurement station. The total energy detection principle in combination with the pulse height weighting technique was applied using C6D6 liquid scintillators as prompt γ-ray detectors. The energy dependence of the neutron flux was measured with ionisation chambers based on the 10B(n, α) reaction. The data were normalised to the isolated and saturated 238U resonance at 6.67 eV. Special procedures were applied to reduce bias effects due to the weighting function, normalization, dead time and background corrections, and corrections related to the sample properties. The total uncertainty due to the weighting function, normalization, neutron flux and sample characteristics is about 1.5%. Resonance parameters were derived from a simultaneous resonance shape analysis of the GELINA capture data and transmission data obtained previously at a 42m and 150m station of ORELA. The parameters of resonances below 500 eV are in good agreement with those resulting from an evaluation that was adopted in the main data libraries. Between 500 eV and 1200 eV a systematic difference in the neutron width is observed. Average capture cross section data were derived from the experimental capture yield in the energy region between 3.5 keV and 90 keV. The results are in good agreement with an evaluated cross section resulting from a least squares fit to experimental data available in the literature prior to this work. The average cross section data derived in this work were parameterised in terms of average resonance parameters and included in a least squares analysis together with other experimental data reported in the literature.

  3. Investigating Regional Disparities of China's Human Development with Cluster Analysis: A Historical Perspective

    ERIC Educational Resources Information Center

    Yang, Yongheng; Hu, Angang

    2008-01-01

    This paper adopts both one-dimensional and multi-dimensional cluster analysis to analyze China's HDI data for 1982, 1995, 1999, and 2003, and to classify China's provinces into four tiers based on the three basic developmental aspects embedded in HDI. The classifications by cluster analysis depends on the observations' similarities with respect to…

  4. Potential Risk of Regional Disease Spread in West Africa through Cross-Border Cattle Trade

    PubMed Central

    Dean, Anna S.; Fournié, Guillaume; Kulo, Abalo E.; Boukaya, G. Aboudou; Schelling, Esther; Bonfoh, Bassirou

    2013-01-01

    Background Transboundary animal movements facilitate the spread of pathogens across large distances. Cross-border cattle trade is of economic and cultural importance in West Africa. This study explores the potential disease risk resulting from large-scale, cross-border cattle trade between Togo, Burkina Faso, Ghana, Benin, and Nigeria for the first time. Methods and Principal Findings A questionnaire-based survey of livestock movements of 226 cattle traders was conducted in the 9 biggest cattle markets of northern Togo in February-March 2012. More than half of the traders (53.5%) operated in at least one other country. Animal flows were stochastically simulated based on reported movements and the risk of regional disease spread assessed. More than three quarters (79.2%, range: 78.1–80.0%) of cattle flowing into the market system originated from other countries. Through the cattle market system of northern Togo, non-neighbouring countries were connected via potential routes for disease spread. Even for diseases with low transmissibility and low prevalence in a given country, there was a high risk of disease introduction into other countries. Conclusions By stochastically simulating data collected by interviewing cattle traders in northern Togo, this study identifies potential risks for regional disease spread in West Africa through cross-border cattle trade. The findings highlight that surveillance for emerging infectious diseases as well as control activities targeting endemic diseases in West Africa are likely to be ineffective if only conducted at a national level. A regional approach to disease surveillance, prevention and control is essential. PMID:24130721

  5. Derivation of water vapour absorption cross-sections in the red region

    NASA Technical Reports Server (NTRS)

    Lal, M.; Chakrabarty, D. K.

    1994-01-01

    Absorption spectrum in 436 to 448 nm wavelength region gives NO2 and O3 column densities. This spectrum can also give H2O column density. The spectrum in the range of 655 to 667 nm contains absorption due to NO3 and H2O. Combining the absorption spectra in the wavelength ranges of 436 to 448 and 655 to 667 nm, water vapor absorption cross-sections in this range comes out to be of the order of 2.0 x 10(exp -24) cm(exp -2).

  6. Pathway-specific regulation revisited: cross-regulation of multiple disparate gene clusters by PAS-LuxR transcriptional regulators.

    PubMed

    Vicente, Cláudia M; Payero, Tamara D; Santos-Aberturas, Javier; Barreales, Eva G; de Pedro, Antonio; Aparicio, Jesús F

    2015-06-01

    PAS-LuxR regulators are highly conserved proteins devoted to the control of antifungal production by binding to operators located in given promoters of polyene biosynthetic genes. The canonical operator of PimM, archetype of this class of regulators, has been used here to search for putative targets of orthologous protein PteF in the genome of Streptomyces avermitilis, finding 97 putative operators outside the pentaene filipin gene cluster (pte). The processes putatively affected included genetic information processing; energy, carbohydrate, and lipid metabolism; DNA replication and repair; morphological differentiation; secondary metabolite biosynthesis; and transcriptional regulation, among others. Seventeen of these operators were selected, and their binding to PimM DNA-binding domain was assessed by electrophoretic mobility shift assays. Strikingly, the protein bound all predicted operators suggesting a direct control over targeted processes. As a proof of concept, we studied the biosynthesis of the ATP-synthase inhibitor oligomycin whose gene cluster included two operators. Regulator mutants showed a severe loss of oligomycin production, whereas gene complementation of the mutant restored phenotype, and gene duplication in the wild-type strain boosted oligomycin production. Comparative gene expression analyses in parental and mutant strains by reverse transcription-quantitative polymerase chain reaction of selected olm genes corroborated production results. These results demonstrate that PteF is able to cross-regulate the biosynthesis of two related secondary metabolites, filipin and oligomycin, but might be extended to all the processes indicated above. This study highlights the complexity of the network of interactions in which PAS-LuxR regulators are involved and opens new possibilities for the manipulation of metabolite production in Streptomycetes.

  7. A novel region-based level set method initialized with mean shift clustering for automated medical image segmentation.

    PubMed

    Bai, Pei Rui; Liu, Qing Yi; Li, Lei; Teng, Sheng Hua; Li, Jing; Cao, Mao Yong

    2013-11-01

    Appropriate initialization and stable evolution are desirable criteria to satisfy in level set methods. In this study, a novel region-based level set method utilizing both global and local image information complementarily is proposed. The global image information is extracted from mean shift clustering without any prior knowledge. Appropriate initial contours are obtained by regulating the clustering results. The local image information, as extracted by a data fitting energy, is employed to maintain a stable evolution of the zero level set curves. The advantages of the proposed method are as follows. First, the controlling parameters of the evolution can be easily estimated by the clustering results. Second, the automaticity of the model increases because of a reduction in computational cost and manual intervention. Experimental results confirm the efficiency and accuracy of the proposed method for medical image segmentation.

  8. Interpretive geologic cross sections for the Death Valley regional flow system and surrounding areas, Nevada and California

    USGS Publications Warehouse

    Sweetkind, D.S.; Dickerson, R.P.; Blakely, R.J.; Denning, P.D.

    2001-01-01

    This report presents a network of 28 geologic cross sections that portray subsurface geologic relations within the Death Valley regional ground-water system, a ground-water basin that encompasses a 3? x 3? area (approximately 70,000 km2) in southern Nevada and eastern California. The cross sections transect that part of the southern Great Basin that includes Death Valley, the Nevada Test Site, and the potential high-level nuclear waste underground repository at Yucca Mountain. The specific geometric relationships portrayed on the cross sections are discussed in the context of four general sub-regions that have stratigraphic similarities and general consistency of structural style: (1) the Nevada Test Site vicinity; (2) the Spring Mountains, Pahrump Valley and Amargosa Desert region; (3) the Death Valley region; and (4) the area east of the Nevada Test Site. The subsurface geologic interpretations portrayed on the cross sections are based on an integration of existing geologic maps, measured stratigraphic sections, published cross sections, well data, and geophysical data and interpretations. The estimated top of pre-Cenozoic rocks in the cross sections is based on inversion of gravity data, but the deeper parts of the sections are based on geologic conceptual models and are more speculative. The region transected by the cross sections includes part of the southern Basin and Range Province, the northwest-trending Walker Lane belt, the Death Valley region, and the northern Mojave Desert. The region is structurally complex, where a locally thick Tertiary volcanic and sedimentary section unconformably overlies previously deformed Proterozoic through Paleozoic rocks. All of these rocks have been deformed by complex Neogene ex-tensional normal and strike-slip faults. These cross sections form a three-dimensional network that portrays the interpreted stratigraphic and structural relations in the region; the sections form part of the geologic framework that will be

  9. Representation of the neutron cross sections of several fertile and fissile nuclei in the resonance regions

    SciTech Connect

    de Saussure, G.; Perez, R.B.

    1981-01-01

    Several aspects of the measurement, analysis and evaluation of the cross sections of the fertile and fissile nuclides in the resonance regions are discussed. In the resolved range, for the fertile nuclides it is thought that the principal requirement for improved evaluations is for a practical methodology to deal with systematic errors and their correlations. For the fissile nuclides /sup 235/U and /sup 239/Pu, the ENDF/B-V evaluations are not consistent with ENDF/B procedures recommendations and fall short of the goals of resonance analysis. New evaluations of these two isotopes should be performed. In the unresolved resonance region it is shown that the ENDF/B representation is ambiguous and is not theoretically justified. A better representation may be desirable, and a validation of the representation with experimental self-shielding and transmission measurements is certainly required. 105 references. (WHK)

  10. Regionalization of Europe based on a K-Means Cluster Analysis of the climate change of temperatures and precipitation

    NASA Astrophysics Data System (ADS)

    Carvalho, M. J.; Melo-Gonçalves, P.; Teixeira, J. C.; Rocha, A.

    2016-08-01

    In order to study climate change on a regional scale using Earth System Models, it is useful to partition the spatial domain into regions according to their climate changes. The aim of this work is to divide the European domain into regions of similar projected climate changes using a simulation of daily total precipitation, minimum and maximum temperatures for the recent-past (1986-2005) and long-term future (2081-2100) provided by the Coupled Model Intercomparison Project (CMIP5). The difference between the long-term future and recent-past daily climatologies of these three variables is determined. Aiming to objectively identify the grid points with coherent climate changes, a K-Mean Cluster Analysis is applied to these differences. This method is performed for each variable independently (univariate version) and for the aggregation of the three variables (multivariate version). A mathematical approach to determine the optimal number of clusters is pursued. However, due to the method characteristics, a sensitivity test to the number of clusters is performed by analysing the consistency of the results. This is a novel method, allowing for the determination of regions based on the climate change of multiple variables. Results from the univariate application of this method are in accordance with results found in the literature, showing overall similar regions of changes. The regions obtained for the multivariate version are mainly defined by latitude over European land, with some features of land-sea interaction. Furthermore, all regions have statistically different distributions of at least one of the variables, providing confidence to the regions obtained.

  11. Seismic Hazard and risk assessment for Romania -Bulgaria cross-border region

    NASA Astrophysics Data System (ADS)

    Simeonova, Stela; Solakov, Dimcho; Alexandrova, Irena; Vaseva, Elena; Trifonova, Petya; Raykova, Plamena

    2016-04-01

    Among the many kinds of natural and man-made disasters, earthquakes dominate with regard to their social and economical impact on the urban environment. Global seismic hazard and vulnerability to earthquakes are steadily increasing as urbanization and development occupy more areas that are prone to effects of strong earthquakes. The assessment of the seismic hazard and risk is particularly important, because it provides valuable information for seismic safety and disaster mitigation, and it supports decision making for the benefit of society. Romania and Bulgaria, situated in the Balkan Region as a part of the Alpine-Himalayan seismic belt, are characterized by high seismicity, and are exposed to a high seismic risk. Over the centuries, both countries have experienced strong earthquakes. The cross-border region encompassing the northern Bulgaria and southern Romania is a territory prone to effects of strong earthquakes. The area is significantly affected by earthquakes occurred in both countries, on the one hand the events generated by the Vrancea intermediate-depth seismic source in Romania, and on the other hand by the crustal seismicity originated in the seismic sources: Shabla (SHB), Dulovo, Gorna Orjahovitza (GO) in Bulgaria. The Vrancea seismogenic zone of Romania is a very peculiar seismic source, often described as unique in the world, and it represents a major concern for most of the northern part of Bulgaria as well. In the present study the seismic hazard for Romania-Bulgaria cross-border region on the basis of integrated basic geo-datasets is assessed. The hazard results are obtained by applying two alternative approaches - probabilistic and deterministic. The MSK64 intensity (MSK64 scale is practically equal to the new EMS98) is used as output parameter for the hazard maps. We prefer to use here the macroseismic intensity instead of PGA, because it is directly related to the degree of damages and, moreover, the epicentral intensity is the original

  12. Neutron and Charged-Particle Induced Cross Sections for Radiochemistry in the Region of Bromine and Krypton

    SciTech Connect

    Hoffman, R; Dietrich, F; Bauer, R; Kelley, K; Mustafa, M

    2004-07-23

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron and proton induced nuclear reaction cross sections in the mass region of bromine and krypton (34 {le} Z {le} 37, 40 {le} N {le} 47).

  13. Neutron and Charged-Particle Induced Cross Sections for Radiochemistry in the Region of Samarium, Europium, and Gadolinium

    SciTech Connect

    Hoffman, R D; Kelley, K; Dietrich, F S; Bauer, R; Mustafa, M

    2004-11-30

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron and proton induced nuclear reaction cross sections in the mass region of samarium, europium and gadolinium (62 {le} Z {le} 64, 82 {le} N {le} 96).

  14. Molecular analysis of region 1 of the Escherichia coli K5 antigen gene cluster: a region encoding proteins involved in cell surface expression of capsular polysaccharide.

    PubMed Central

    Pazzani, C; Rosenow, C; Boulnois, G J; Bronner, D; Jann, K; Roberts, I S

    1993-01-01

    The nucleotide sequence of region 1 of the K5 antigen gene cluster of Escherichia coli was determined. This region is postulated to encode functions which, at least in part, participate in translocation of polysaccharide across the periplasmic space and onto the cell surface. Analysis of the nucleotide sequence revealed five genes that encode proteins with predicted molecular masses of 75.7, 60.5, 44, 43, and 27 kDa. The 27-kDa protein was 70.7% homologous to the CMP-2-keto-3-deoxyoctulosonic acid synthetase enzyme encoded by the E. coli kdsB gene, indicating the presence of a structural gene for a similar enzyme within the region 1 operon. The 43-kDa protein was homologous to both the Ctrb and BexC proteins encoded by the Neisseria meningitidis and Haemophilus influenzae capsule gene clusters, respectively, indicating common stages in the expression of capsules in these gram-negative bacteria. However, no homology was detected between the 75.7, 60.5-, and 44-kDa proteins and any of the proteins so far described for the H. influenzae and N. meningitidis capsule gene clusters. Images PMID:8397187

  15. Prediction of maize single cross hybrids using the total effects of associated markers approach assessed by cross-validation and regional trials.

    PubMed

    Melo, Wagner Mateus Costa; Pinho, Renzo Garcia Von; Balestre, Marcio

    2014-01-01

    The present study aimed to predict the performance of maize hybrids and assess whether the total effects of associated markers (TEAM) method can correctly predict hybrids using cross-validation and regional trials. The training was performed in 7 locations of Southern Brazil during the 2010/11 harvest. The regional assays were conducted in 6 different South Brazilian locations during the 2011/12 harvest. In the training trial, 51 lines from different backgrounds were used to create 58 single cross hybrids. Seventy-nine microsatellite markers were used to genotype these 51 lines. In the cross-validation method the predictive accuracy ranged from 0.10 to 0.96, depending on the sample size. Furthermore, the accuracy was 0.30 when the values of hybrids that were not used in the training population (119) were predicted for the regional assays. Regarding selective loss, the TEAM method correctly predicted 50% of the hybrids selected in the regional assays. There was also loss in only 33% of cases; that is, only 33% of the materials predicted to be good in training trial were considered to be bad in regional assays. Our results show that the predictive validation of different crop conditions is possible, and the cross-validation results strikingly represented the field performance.

  16. Star formation activity of intermediate redshift cluster galaxies out to the infall regions

    NASA Astrophysics Data System (ADS)

    Gerken, B.; Ziegler, B.; Balogh, M.; Gilbank, D.; Fritz, A.; Jäger, K.

    2004-07-01

    We present a spectroscopic analysis of two galaxy clusters at z≈0.2, out to ˜4 Mpc. The two clusters VMF73 and VMF74 as identified by \\citet{VMFJQH98} were observed with multiple object spectroscopy using MOSCA at the Calar Alto 3.5 m telescope. Both clusters lie in the ROSAT Position Sensitive Proportional Counter field R285 and were selected from the X-ray Dark Cluster Survey \\citep{GBCZ04} that provides optical V- and I-band data. VMF73 and VMF74 are located at respective redshifts of z=0.25 and z=0.18 with velocity dispersions of 671 km s-1 and 442 km s-1, respectively. Both cluster velocity dispersions are consistent with Gaussians. The spectroscopic observations reach out to ˜2.5 virial radii. Line strength measurements of the emission lines Hα and [O II]λ3727 are used to assess the star formation activity of cluster galaxies which show radial and density dependences. The mean and median of both line strength distributions as well as the fraction of star forming galaxies increase with increasing clustercentric distance and decreasing local galaxy density. Except for two galaxies with strong Hα and [O II] emission, all of the cluster galaxies are normal star forming or passive galaxies. Our results are consistent with other studies that show the truncation in star formation occurs far from the cluster centre. Table A.1 is only available in electronic from at http//www.edpsciences.org

  17. Nutrition, environment and cardiovascular health (NESCAV): protocol of an inter-regional cross-sectional study

    PubMed Central

    2010-01-01

    Background Despite the remarkable technological progress in health care and treatment, cardiovascular disease remains the leading cause of premature death, prolonged hospitalization and disability in most European countries. In the population of the Greater Region (Grand-Duchy of Luxembourg, Wallonia in Belgium, and Lorraine in France), the prevalence of cardiovascular risk factors and disease is among the highest in Europe, warranting the need for a better understanding of factors contributing to this pattern. In this context, the cross-border "Nutrition, Environment and Cardiovascular Health-NESCAV" project is initiated by an inter-regional multi-disciplinary consortium and supported by the INTERREG IV A program "Greater Region", 2007-2013, to fight synergically and harmoniously against this major public health problem. Methods/design The objectives of the three-year planned project are to assess, in a representative sample of 3000 randomly selected individuals living at the Greater Region, 1) the cardiovascular health and risk profile, 2) the association between the dietary habits and the cardiovascular risk, 3) the association of occupational and environmental pollution markers with the cardiovascular risk, 4) the knowledge, awareness and level of control of cardiovascular risk factors, 5) the potential gaps in the current primary prevention, and finally, to address evidence-based recommendations enabling the development of inter-regional guidance to help policy-makers and health care workers for the prevention of cardiovascular disease. Discussion The findings will provide tools that may enable the Greater Region's decision-makers and health professionals to implement targeted and cost-effective prevention strategies. PMID:21078172

  18. The galaxy populations from the centers to the infall regions in z ≈ 0.25 clusters

    NASA Astrophysics Data System (ADS)

    Verdugo, M.; Ziegler, B. L.; Gerken, B.

    2008-07-01

    Context: In the local universe, the relative fractions of galaxy types differs in galaxy clusters in comparison to the field. Observations at higher redshift provide evidence that cluster galaxies evolve with lookback time. This could be due either to the late assembly of clusters, which is predicted by bottom-up scenarios of structure formation, or to cluster-specific interaction processes. Aims: To disentangle various effects, we explore the evolutionary status of galaxies from the center of clusters out to their infall regions in z≈0.25 clusters. Methods: We conducted a panoramic spectroscopic campaign with MOSCA at the Calar Alto observatory. We acquired low-resolution spectra of more than 500 objects. Approximately 150 of these spectra were of galaxies that are members of six different clusters, which differ in intrinsic X-ray luminosity. The wavelength range allows us to quantify the star formation activity by using the [Oii] and the Hα emission lines. This activity is examined in terms of the large-scale environment expressed by the clustercentric distance of the galaxies as well as on local scales given by the spatial galaxy densities. Results: The general decline in star-formation activity observed for galaxies inside nearby clusters is also seen at z≈0.25. A global suppression of star-formation is detected in the outskirts of clusters, at about 3R_virial, where the galaxy densities are low and the intra-cluster medium is very shallow. Galaxies with ongoing star-formation have similar activity, regardless of the environment. Therefore, the decline of the star-formation activity inside the investigated clusters is driven mainly by the significant change in the fraction of active versus passive populations. This suggests that the suppression of the star-formation activity occurs on short timescales. We detect a significant population of red star-forming galaxies whose colors are consistent with the red-sequence of passive galaxies. They appear to be in

  19. A YOUNG STELLAR CLUSTER WITHIN THE RCW41 H II REGION: DEEP NIR PHOTOMETRY AND OPTICAL/NIR POLARIMETRY

    SciTech Connect

    Santos, Fabio P.; Franco, Gabriel A. P.; Roman-Lopes, Alexandre E-mail: franco@fisica.ufmg.br

    2012-06-01

    The RCW41 star-forming region is embedded within the Vela Molecular Ridge, hosting a massive stellar cluster surrounded by a conspicuous H II region. Understanding the role of interstellar magnetic fields and studying the newborn stellar population is crucial to building a consistent picture of the physical processes acting on this kind of environment. We carried out a detailed study of the interstellar polarization toward RCW41 with data from an optical and near-infrared polarimetric survey. Additionally, deep near-infrared images from the 3.5 meter New Technology Telescope were used to study the photometric properties of the embedded young stellar cluster, revealing several YSO candidates. By using a set of pre-main-sequence isochrones, a mean cluster age in the range 2.5-5.0 million years was determined, and evidence of sequential star formation was revealed. An abrupt decrease in R-band polarization degree was noticed toward the central ionized area, probably due to low grain alignment efficiency caused by the turbulent environment and/or the weak intensity of magnetic fields. The distortion of magnetic field lines exhibits dual behavior, with the mean orientation outside the area approximately following the borders of the star-forming region and directed radially toward the cluster inside the ionized area, in agreement with simulations of expanding H II regions. The spectral dependence of polarization allowed a meaningful determination of the total-to-selective extinction ratio by fittings of the Serkowski relation. Furthermore, a large rotation of polarization angle as a function of wavelength was detected toward several embedded stars.

  20. A Young Stellar Cluster within the RCW41 H II Region: Deep NIR Photometry and Optical/NIR Polarimetry

    NASA Astrophysics Data System (ADS)

    Santos, Fábio P.; Roman-Lopes, Alexandre; Franco, Gabriel A. P.

    2012-06-01

    The RCW41 star-forming region is embedded within the Vela Molecular Ridge, hosting a massive stellar cluster surrounded by a conspicuous H II region. Understanding the role of interstellar magnetic fields and studying the newborn stellar population is crucial to building a consistent picture of the physical processes acting on this kind of environment. We carried out a detailed study of the interstellar polarization toward RCW41 with data from an optical and near-infrared polarimetric survey. Additionally, deep near-infrared images from the 3.5 meter New Technology Telescope were used to study the photometric properties of the embedded young stellar cluster, revealing several YSO candidates. By using a set of pre-main-sequence isochrones, a mean cluster age in the range 2.5-5.0 million years was determined, and evidence of sequential star formation was revealed. An abrupt decrease in R-band polarization degree was noticed toward the central ionized area, probably due to low grain alignment efficiency caused by the turbulent environment and/or the weak intensity of magnetic fields. The distortion of magnetic field lines exhibits dual behavior, with the mean orientation outside the area approximately following the borders of the star-forming region and directed radially toward the cluster inside the ionized area, in agreement with simulations of expanding H II regions. The spectral dependence of polarization allowed a meaningful determination of the total-to-selective extinction ratio by fittings of the Serkowski relation. Furthermore, a large rotation of polarization angle as a function of wavelength was detected toward several embedded stars. Based on observations collected at the European Southern Observatory (La Silla, Chile), National Optical Astronomy Observatory (CTIO, Chile), and Observatório do Pico dos Dias, operated by Laboratório Nacional de Astrofísica (LNA/MCT, Brazil).

  1. Integrated land use and regional resource management--a cross-disciplinary dialogue on future perspectives for a sustainable development of regional resources.

    PubMed

    Fürst, Christine; Helming, Katharina; Lorz, Carsten; Müller, Felix; Verburg, Peter H

    2013-09-01

    Our paper introduces objectives and ideas of the special issue "Integrated land use and regional resource management - A cross-disciplinary dialogue on future perspectives for a sustainable development of regional resources" and provides an overview on the contributions of the single papers in the special issue to this topic. Furthermore, we discuss and present major challenges and demands on integrated land use and regional resource management and we come up with an analytical framework how to correspond these demands.

  2. Flux Transfer Event in the Subsolar Region and Near the Cusp: Simultaneous Polar and Cluster Observations

    NASA Technical Reports Server (NTRS)

    Le, G.; Zheng, Y.; Russell, C. T.; Pfaff, R. F.; Slavin, J. A.; Lin, N.; Mozer, F.; Parks, G.; Petrinec, S. M.; Lucek, e. A.; Reme, Henri

    2005-01-01

    The phenomenon called flux transfer events (FTEs) is widely accepted as the manifestation of time-dependent reconnection. In this paper, we present an observational evidence of a flux transfer event observed simultaneously at low-latitude by Polar and high-latitude by Cluster. This event occurred on March 21, 2002, when both Cluster and Polar were located near the local noon but with large latitudinal distance. Cluster was moving outbound from polar cusp to the magnetosheath, and Polar was in the magnetosheath near the equatorial magnetopause. The observations show that a flux transfer event was formed between the equator and the northern cusp. Polar and Cluster observed the FTE's two open flux tubes: Polar saw the southward moving flux tube near the equator; and Cluster the , northward moving flux tube at high latitude. Unlike low-latitude FTEs, the high-latitude FTE did not exhibit the characteristic bi-polar BN signature. But the plasma data clearly showed its open flux tube configuration. Enhanced electric field fluctuations were observed within the FTE core, both at low- and high-attitudes. This event provides us a unique opportunity to understand high-latitude FTE signatures and the nature of time-varying reconnection.

  3. Association between payments from manufacturers of pharmaceuticals to physicians and regional prescribing: cross sectional ecological study

    PubMed Central

    Agrawal, Shantanu; King, Marissa; Venkatesh, Arjun K; Krumholz, Harlan M; McKee, Douglas; Brown, Douglas; Ross, Joseph S

    2016-01-01

    Objective To examine the association between payments made by the manufacturers of pharmaceuticals to physicians and prescribing by physicians within hospital referral regions. Design Cross sectional analysis of 2013 and 2014 Open Payments and Medicare Part D prescribing data for two classes of commonly prescribed, commonly marketed drugs: oral anticoagulants and non-insulin diabetes drugs, overall and stratified by physician and payment type. Setting 306 hospital referral regions, United States. Participants 45 949 454 Medicare Part D prescriptions written by 623 886 physicians to 10 513 173 patients for two drug classes: oral anticoagulants and non-insulin diabetes drugs. Main outcome measures Proportion, or market share, of marketed oral anticoagulants and non-insulin diabetes drugs prescribed by physicians among all drugs in each class and within hospital referral regions. Results Among 306 hospital referral regions, there were 977 407 payments to physicians totaling $61 026 140 (£46 174 600; €54 632 500) related to oral anticoagulants, and 1 787 884 payments totaling $108 417 616 related to non-insulin diabetes drugs. The median market share of the hospital referral regions was 21.6% for marketed oral anticoagulants and 12.6% for marketed non-insulin diabetes drugs. Among hospital referral regions, one additional payment (median value $13, interquartile range, $10-$18) was associated with 94 (95% confidence interval 76 to 112) additional days filled of marketed oral anticoagulants and 107 (89 to 125) additional days filled of marketed non-insulin diabetes drugs (P<0.001). Payments to specialists were associated with greater prescribing of marketed drugs than payments to non-specialists (212 v 100 additional days filled per payment of marketed oral anticoagulants, 331 v 114 for marketed non-insulin diabetes drugs, P<0.001). Payments for speaker and consulting fees for non-insulin diabetes drugs were associated with

  4. Space, energy and anisotropy effects on effective cross sections and diffusion coefficients in the resonance region

    SciTech Connect

    Meftah, B.

    1982-01-01

    Present methods used in reactor analysis do not include adequately the effect of anisotropic scattering in the calculation of resonance effective cross sections. Also the assumption that the streaming term ..cap omega...del Phi is conserved when the total, absorption and transfer cross sections are conserved, is bad because the leakage from a heterogeneous cell will not be conserved and is strongly anisotropic. A third major consideration is the coupling between different regions in a multiregion reactor; currently this effect is being completely ignored. To assess the magnitude of these effects, a code based on integral transport formalism with linear anisotropic scattering was developed. Also, a more adequate formulation of the diffusion coefficient in a heterogeneous cell was derived. Two reactors, one fast, ZPR-6/5, and one thermal, TRX-3, were selected for the study. The study showed that, in general, the inclusion of linear scattering anisotropy increases the cell effective capture cross section of U-238. The increase was up to 2% in TRX-3 and 0.5% in ZPR-6/5. The effect on the multiplication factor was -0.003% ..delta..k/k for ZPR-6/5 and -0.05% ..delta..k/k for TRX-3. For the case of the diffusion coefficient, the combined effect of heterogeneity and linear anisotropy gave an increase of up to 29% in the parallel diffusion coefficient of TRX-3 and 5% in the parallel diffusion coefficient of ZPR-6/5. In contrast, the change in the perpendicular diffusion coefficient did not exceed 2% in both systems.

  5. Studying the Permian cross-section (Volga region) using chemical and isotopic investigations

    NASA Astrophysics Data System (ADS)

    Gareev, Bulat; Georgii, Batalin; Nurgaliev, Danis; Nurgalieva, Nuriya

    2016-04-01

    This paper presents a study of international important site: the cross-section of Permian system's Urzhumian Stage in the ravine "Pechischy". Outcrop is located on the right bank of the Volga River (about 10 km West of Kazan). It has local, regional and planetary correlation features and also footprints of different geographical scale events. The main objective in the research is the deep study of sediments using chemical and isotopic investigations. XRF spectrometer was used for chemical investigations of samples. Chemistry of carbonates and clastic rocks includes the analysis of chemical elements, compounds, petrochemical (lithogeochemical) modules for the interpretation of the genesis of lithotypes. For the review of the geochemistry of stable isotopes of carbon (oxygen) we used IRMS. The main objective is the nature of the isotope fractionation issues, to addressing the issues of stratigraphy and paleogeography. The measurements have shown the variability of chemical parameters in cross-section. It gives us opportunity to see small changes in sedimentation and recognize the factors that influence to the process. The work was carried out according to the Russian Government's Program of Competitive Growth of Kazan Federal University, supported by the grant provided to the Kazan State University for performing the state program in the field of scientific research.

  6. Cross-stream ejection in the inter-wheel region of aircraft landing gears

    NASA Astrophysics Data System (ADS)

    McCarthy, Philip; Ekmekci, Alis

    2014-11-01

    The reduction of aircraft noise is an important challenge currently faced by aircraft manufacturers. During approach and landing, the landing gears contribute a significant proportion of the aircraft generated noise. It is therefore critical that the key noise sources be identified and understood in order for effective mitigation methods to be developed. For a simplified two-wheel nose landing gear, a strong cross stream flow ejection phenomena has been observed to occur in the inter-wheel region in presence of wheel wells. The location and orientation of these flow ejections causes highly unsteady, three dimensional flow between the wheels that may impinge on other landing gear components, thereby potentially acting as a significant noise generator. The effects of changing the inter-wheel geometry (inter-wheel spacing, the wheel well depth and main strut geometry) upon the cross-stream ejection behaviour has been experimentally investigated using both qualitative flow visualisation and quantitative PIV techniques. A summary of the key results will be presented for the three main geometrical parameters under examination and the application of these findings to real life landing gears will be discussed. Thanks to Messier-Bugatti-Dowty and NSERC for their support for this project.

  7. Towards tract-specific fractional anisotropy (TSFA) at crossing-fiber regions with clinical diffusion MRI

    PubMed Central

    Mishra, Virendra; Guo, Xiaohu; Delgado, Mauricio R.; Huang, Hao

    2014-01-01

    Purpose White matter fractional anisotropy (FA), a measure implying microstructure, is significantly underestimated with single diffusion tensor model at crossing-fiber regions (CFR). We propose a tract-specific FA (TSFA), corrected for the effects of crossing-fiber geometry and free water at CFR, and adapted for tract analysis with diffusion MRI (dMRI) in clinical research. Methods At CFR voxels, the proposed technique estimates free water fraction (fiso) as a linear function of mean apparent diffusion coefficient (mADC), fits the dual tensors and estimates TSFA. Digital phantoms were designed for testing the accuracy of fiso and fitted dual-anisotropies at CFR. The technique was applied to clinical dMRI of normal subjects and hereditary spastic paraplegia (HSP) patients to test the effectiveness of TSFA. Results Phantom simulation showed unbiased estimates of dual-tensor anisotropies at CFR and high accuracy of fiso as a linear function of mADC. TSFA at CFR was highly consistent to the single tensor FA at non-CFR within the same tract with normal human dMRI. Additional HSP imaging biomarkers with significant correlation to clinical motor function scores could be identified with TSFA. Conclusion Results suggest the potential of the proposed technique in estimating unbiased TSFA at CFR and conducting tract analysis in clinical research. PMID:25447208

  8. Cross-sectional survey on helminth infections of chickens in the Samsun region, Turkey.

    PubMed

    Kurt, M; Acici, M

    2008-06-01

    A cross-sectional survey was performed to determine the prevalence and intensity of helminth infections in 185 chickens from nine districts in the Samsun region, northern Turkey between July 1999 and June 2000. In total, 88% of 83 scavenging chickens and 4% of 52 layers from laying batteries were infected, but none of the 50 broilers harboured helminths in the alimentary tract or trachea. The difference in prevalence was statistically significant among broilers, layers from laying batteries and scavenging chickens. A total of 16 different species were detected. The helminth species found were: Davainea proglottina (23%), Raillietina echinobothrida (13%), Raillietina cesticillus (12%), Hymenolepis carioca (10%), Raillietina tetragona (6%), Choanotaenia. infundibulum (2%), Amoebotaenia cuneata (2%), Echinoparyhium recurvatum (1%), Echinostoma revolutum (1%), Heterakis gallinarum (29%), Ascaridia galli (16%), Capillaria caudinflata (12%), Capillaria retusa (6%), Capillaria bursata (4%), Capillaria annulata (1%) and Syngamus trachea (2%).

  9. Cross-region reduction in 5-hydroxymethylcytosine in Alzheimer's disease brain.

    PubMed

    Condliffe, Daniel; Wong, Andrew; Troakes, Claire; Proitsi, Petroula; Patel, Yogen; Chouliaras, Leonidas; Fernandes, Cathy; Cooper, Jonathan; Lovestone, Simon; Schalkwyk, Leonard; Mill, Jonathan; Lunnon, Katie

    2014-08-01

    Epigenetic processes play a key role in the central nervous system and altered levels of 5-methylcytosine have been associated with a number of neurologic phenotypes, including Alzheimer's disease (AD). Recently, 3 additional cytosine modifications have been identified (5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxylcytosine), which are thought to be intermediate steps in the demethylation of 5-methylcytosine to unmodified cytosine. Little is known about the frequency of these modifications in the human brain during health or disease. In this study, we used immunofluorescence to confirm the presence of each modification in human brain and investigate their cross-tissue abundance in AD patients and elderly control samples. We identify a significant AD-associated decrease in global 5-hydroxymethylcytosine in entorhinal cortex and cerebellum, and differences in 5-formylcytosine levels between brain regions. Our study further implicates a role for epigenetic alterations in AD.

  10. Measurement of Neutron Capture Cross Section of 62Ni in the keV-Region

    SciTech Connect

    Alpizar-Vicente, A. M.; Hatarik, R.; Bredeweg, T. A.; Esch, E.-I.; Haight, R. C.; O'Donnell, J. M.; Reifarth, R.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Greife, U.

    2006-03-13

    The neutron capture cross section of 62Ni, relative to gold as a standard, was determined in the energy range from 250 eV to 100 keV. This energy range covers the region between 5 keV to 20 keV, which is not available in ENDF. Capture events are detected with the 160-fold 4{pi} BaF2 Detector for Advanced Neutron Capture Experiments (DANCE) at the Los Alamos Neutron Science Center. One of the challenges was to process the high count rate of 4 MHz, which required an optimization of the data acquisition software. The neutron energy was determined by the time-of-flight technique using a flight path of 20.25 m. The sample mass of the 96% enriched 62Ni target was 210 mg and it was mounted in a 1.5 {mu}m thick Mylar foil.

  11. Cross-comparison of leaching strains isolated from two different regions: Chambishi and Dexing copper mines.

    PubMed

    Ngom, Baba; Liang, Yili; Liu, Xueduan

    2014-01-01

    A cross-comparison of six strains isolated from two different regions, Chambishi copper mine (Zambia, Africa) and Dexing copper mine (China, Asia), was conducted to study the leaching efficiency of low grade copper ores. The strains belong to the three major species often encountered in bioleaching of copper sulfide ores under mesophilic conditions: Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferriphilum. Prior to their study in bioleaching, the different strains were characterized and compared at physiological level. The results revealed that, except for copper tolerance, strains within species presented almost similar physiological traits with slight advantages of Chambishi strains. However, in terms of leaching efficiency, native strains always achieved higher cell density and greater iron and copper extraction rates than the foreign microorganisms. In addition, microbial community analysis revealed that the different mixed cultures shared almost the same profile, and At. ferrooxidans strains always outcompeted the other strains.

  12. Cross-Comparison of Leaching Strains Isolated from Two Different Regions: Chambishi and Dexing Copper Mines

    PubMed Central

    Ngom, Baba; Liang, Yili; Liu, Xueduan

    2014-01-01

    A cross-comparison of six strains isolated from two different regions, Chambishi copper mine (Zambia, Africa) and Dexing copper mine (China, Asia), was conducted to study the leaching efficiency of low grade copper ores. The strains belong to the three major species often encountered in bioleaching of copper sulfide ores under mesophilic conditions: Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferriphilum. Prior to their study in bioleaching, the different strains were characterized and compared at physiological level. The results revealed that, except for copper tolerance, strains within species presented almost similar physiological traits with slight advantages of Chambishi strains. However, in terms of leaching efficiency, native strains always achieved higher cell density and greater iron and copper extraction rates than the foreign microorganisms. In addition, microbial community analysis revealed that the different mixed cultures shared almost the same profile, and At. ferrooxidans strains always outcompeted the other strains. PMID:25478575

  13. Absorption cross-sections of ozone in the ultraviolet and visible spectral regions: Status report 2015

    NASA Astrophysics Data System (ADS)

    Orphal, Johannes; Staehelin, Johannes; Tamminen, Johanna; Braathen, Geir; De Backer, Marie-Renée; Bais, Alkiviadis; Balis, Dimitris; Barbe, Alain; Bhartia, Pawan K.; Birk, Manfred; Burkholder, James B.; Chance, Kelly; von Clarmann, Thomas; Cox, Anthony; Degenstein, Doug; Evans, Robert; Flaud, Jean-Marie; Flittner, David; Godin-Beekmann, Sophie; Gorshelev, Viktor; Gratien, Aline; Hare, Edward; Janssen, Christof; Kyrölä, Erkki; McElroy, Thomas; McPeters, Richard; Pastel, Maud; Petersen, Michael; Petropavlovskikh, Irina; Picquet-Varrault, Benedicte; Pitts, Michael; Labow, Gordon; Rotger-Languereau, Maud; Leblanc, Thierry; Lerot, Christophe; Liu, Xiong; Moussay, Philippe; Redondas, Alberto; Van Roozendael, Michel; Sander, Stanley P.; Schneider, Matthias; Serdyuchenko, Anna; Veefkind, Pepijn; Viallon, Joële; Viatte, Camille; Wagner, Georg; Weber, Mark; Wielgosz, Robert I.; Zehner, Claus

    2016-09-01

    . For ground-based Light Detection and Ranging (LIDAR) measurements the use of BDM (1995) or SER (2014) is recommended. For satellite retrieval the presently widely used data of BDM (1995) should be used because SER (2014) seems less suitable for retrievals that use wavelengths close to 300 nm due to a deficiency in the signal-to-noise ratio in the SER (2014) dataset. The work of ACSO also showed: The need to continue laboratory cross-section measurements of ozone of highest quality. The importance of careful characterization of the uncertainties of the laboratory measurements. The need to extend the scope of such studies to other wavelength ranges (particularly to cover not only the Huggins band but also the comparison with the mid-infrared region). The need for regular cooperation of experts in spectral laboratory measurements and specialists in atmospheric (ozone) measurements.

  14. [Medicen Paris Région: A world-class ''competitiveness cluster'' in the Paris region incorporating a neuroscience ''subcluster''].

    PubMed

    Canet, Emmanuel

    2007-04-01

    The French public-private partnerships known as "competitive clusters" [pôles de compétitivité (PdC)] are intended to be novel and ambitious engines of regional growth, employment and biomedical innovation. Partly funded by government and local councils, they aim to capitalize on regional expertise by bringing together basic scientists, clinicians, innovative entrepreneurs and local decision-makers around specific themes that have become too costly and complex for any of these actors to tackle alone. Clusters provide the critical mass required both to underpin innovation potential and to authenticate regional claims to international competitiveness. Medicen is a biomedicine and therapeutics cluster comprising 120 partners from four broad "colleges" in the greater Paris region: major industry, small and medium-sized businesses, teaching hospitals/State research bodies, and local councils. Chief among its cooperative R&D projects is the neuroscience subcluster, in which "TransAl" the neurodegenerative disease project, counts Sanofi-Aventis, Servier and the French Atomic Energy Commission [Commissariat à l'Energie Atomique (CEA)] as key partners. One main aim is to develop an experimental model in rhesus monkeys in which a putative cause of Alzheimer's disease, intracerebral accumulation of b-amyloid peptide, is generated by impairing the peptide's clearance. The other aim, in which the nuclear medicine expertise of the CEA will be crucial, is to identify, characterize and validate markers for magnetic resonance and positron emission tomography imaging, and to source biomarkers from cerebrospinal fluid proteomics. A human biological resource centre (DNA and tissue banks) project dedicated to neurological and psychiatric disease should be up and running in 2007. Only through fundamental restructuring of resources on such a large cooperative scale are solutions likely to be found to the major problems of modern medicine, bringing healthcare and regional

  15. CisMols Analyzer: identification of compositionally similar cis-element clusters in ortholog conserved regions of coordinately expressed genes

    PubMed Central

    Jegga, Anil G.; Gupta, Ashima; Gowrisankar, Sivakumar; Deshmukh, Mrunal A.; Connolly, Steven; Finley, Kevin; Aronow, Bruce J.

    2005-01-01

    Combinatorial interactions of sequence-specific trans-acting factors with localized genomic cis-element clusters are the principal mechanism for regulating tissue-specific and developmental gene expression. With the emergence of expanding numbers of genome-wide expression analyses, the identification of the cis-elements responsible for specific patterns of transcriptional regulation represents a critical area of investigation. Computational methods for the identification of functional cis-regulatory modules are difficult to devise, principally because of the short length and degenerate nature of individual cis-element binding sites and the inherent complexity that is generated by combinatorial interactions within cis-clusters. Filtering candidate cis-element clusters based on phylogenetic conservation is helpful for an individual ortholog gene pair, but combining data from cis-conservation and coordinate expression across multiple genes is a more difficult problem. To approach this, we have extended an ortholog gene-pair database with additional analytical architecture to allow for the analysis and identification of maximal numbers of compositionally similar and phylogenetically conserved cis-regulatory element clusters from a list of user-selected genes. The system has been successfully tested with a series of functionally related and microarray profile-based co-expressed ortholog pairs of promoters and genes using known regulatory regions as training sets and co-expressed genes in the olfactory and immunohematologic systems as test sets. CisMols Analyzer is accessible via a Web interface at . PMID:15980500

  16. The heptide repeat 2 and upstream region of TGEV induces potent cross-neutralizing antibodies against group I coronaviruses.

    PubMed

    Shi, Huiling; Wu, Nannan; Wang, Xiaoming; Wang, Tianhou

    2012-10-01

    The coronavirus heptide repeat (HR) region in the spike protein induces neutralizing antibodies that block the postfusion core formation and inhibit virus entry into target cells. The HR2 regions for coronaviruses of the same serogroup share high homology. We found that polyclonal antibodies derived from transmissible gastroenteritis coronavirus HR2 and upstream region were cross-reactive with the S proteins of the same serogroup in western blotting. The polyclonal antibodies also potently cross-neutralized viruses from the same serogroup. This study provides new insight for designing vaccine and therapeutic reagents against coronavirus infections.

  17. Neutron Cross Section Processing Methods for Improved Integral Benchmarking of Unresolved Resonance Region Evaluations

    NASA Astrophysics Data System (ADS)

    Walsh, Jonathan A.; Forget, Benoit; Smith, Kord S.; Brown, Forrest B.

    2016-03-01

    In this work we describe the development and application of computational methods for processing neutron cross section data in the unresolved resonance region (URR). These methods are integrated with a continuous-energy Monte Carlo neutron transport code, thereby enabling their use in high-fidelity analyses. Enhanced understanding of the effects of URR evaluation representations on calculated results is then obtained through utilization of the methods in Monte Carlo integral benchmark simulations of fast spectrum critical assemblies. First, we present a so-called on-the-fly (OTF) method for calculating and Doppler broadening URR cross sections. This method proceeds directly from ENDF-6 average unresolved resonance parameters and, thus, eliminates any need for a probability table generation pre-processing step in which tables are constructed at several energies for all desired temperatures. Significant memory reduction may be realized with the OTF method relative to a probability table treatment if many temperatures are needed. Next, we examine the effects of using a multi-level resonance formalism for resonance reconstruction in the URR. A comparison of results obtained by using the same stochastically-generated realization of resonance parameters in both the single-level Breit-Wigner (SLBW) and multi-level Breit-Wigner (MLBW) formalisms allows for the quantification of level-level interference effects on integrated tallies such as keff and energy group reaction rates. Though, as is well-known, cross section values at any given incident energy may differ significantly between single-level and multi-level formulations, the observed effects on integral results are minimal in this investigation. Finally, we demonstrate the calculation of true expected values, and the statistical spread of those values, through independent Monte Carlo simulations, each using an independent realization of URR cross section structure throughout. It is observed that both probability table

  18. Clustering of and risk factors for the porcine high fever disease in a region of Vietnam.

    PubMed

    Le, H; Poljak, Z; Deardon, R; Dewey, C E

    2012-02-01

    Porcine high fever disease (PHFD) emerged in 2006 in China and spread to Vietnam. Little work has been carried out to investigate PHFD risk factors and space-time dynamics. To fill this gap, we investigated probable cases of PHFD at household level as the outcome. A study area, approximately 100 sq. km, was selected from a province of southern Vietnam that had reported the outbreak of PHFD in 2008. A survey was conducted in the study area to collect information about swine health problems during 2008. The questionnaire included three sections: general information, clinical signs of disease in pigs and production factors believed to be risk factors. Cases were defined at the household level and included interpretation of clinical signs in series. Logistic regression with a random intercept at the hamlet level was used to assess risk factors for PHFD at the household level. Spatial clustering was investigated using the D-function and a Cuzick-Edward's test. Spatial clusters were evaluated using a spatial relative risk surface and the spatial scan statistic using a Bernoulli model. Space-time clustering was explored using a space-time K-function and Knox's test. Space-time clusters were evaluated using a space-time permutation model in SaTScan. Of 955 households with questionnaire data, 33.4% were classified as cases. The statistical significance of space and space-time clustering differed between methods employed. The risk factors associated with occurrence of cases were higher numbers of sows and finishing pigs (log 2 transformed), receiving pigs from an external source and the interaction between using 'water green crop' (WGC) as pig feed and owning ducks with or without direct contact with pigs. The interaction between the presence of ducks and feeding WGC to pigs suggested the involvement of pathogens that might be present in water (environment) and could further replicate in or on ducks.

  19. Interpretive geologic cross sections for the Death Valley regional flow system and surrounding areas, Nevada and California

    SciTech Connect

    D.S. Sweetkind; R.P. Dickerson; R.J. Blakely; P.D. Denning

    2001-11-09

    This report presents a network of 28 geologic cross sections that portray subsurface geologic relations within the Death Valley regional ground-water system, a ground-water basin that encompasses a 3 degree x 3 degree area (approximately 70,000 square kilometers) in southern Nevada and eastern California. The cross sections transect that part of the southern Great Basin that includes Death Valley, the Nevada Test Site, and the potential high-level nuclear waste underground repository at Yucca Mountain. The specific geometric relationships portrayed on the cross sections are discussed in the context of four general sub-regions that have stratigraphic similarities and general consistency of structural style: (1) the Nevada Test Site vicinity; (2) the Spring Mountains, Pahrump Valley and Amargosa Desert region; (3) the Death Valley region; and (4) the area east of the Nevada Test Site. The subsurface geologic interpretations portrayed on the cross sections are based on an integration of existing geologic maps, measured stratigraphic sections, published cross sections, well data, and geophysical data and interpretations. The estimated top of pre-Cenozoic rocks in the cross sections is based on inversion of gravity data, but the deeper parts of the sections are based on geologic conceptual models and are more speculative.

  20. Clustering of diet- and activity-related parenting practices: cross-sectional findings of the INPACT study

    PubMed Central

    2013-01-01

    Background Various diet- and activity-related parenting practices are positive determinants of child dietary and activity behaviour, including home availability, parental modelling and parental policies. There is evidence that parenting practices cluster within the dietary domain and within the activity domain. This study explores whether diet- and activity-related parenting practices cluster across the dietary and activity domain. Also examined is whether the clusters are related to child and parental background characteristics. Finally, to indicate the relevance of the clusters in influencing child dietary and activity behaviour, we examined whether clusters of parenting practices are related to these behaviours. Methods Data were used from 1480 parent–child dyads participating in the Dutch IVO Nutrition and Physical Activity Child cohorT (INPACT). Parents of children aged 8–11 years completed questionnaires at home assessing their diet- and activity-related parenting practices, child and parental background characteristics, and child dietary and activity behaviours. Principal component analysis (PCA) was used to identify clusters of parenting practices. Backward regression analysis was used to examine the relationship between child and parental background characteristics with cluster scores, and partial correlations to examine associations between cluster scores and child dietary and activity behaviours. Results PCA revealed five clusters of parenting practices: 1) high visibility and accessibility of screens and unhealthy food, 2) diet- and activity-related rules, 3) low availability of unhealthy food, 4) diet- and activity-related positive modelling, and 5) positive modelling on sports and fruit. Low parental education was associated with unhealthy cluster 1, while high(er) education was associated with healthy clusters 2, 3 and 5. Separate clusters were related to both child dietary and activity behaviour in the hypothesized directions: healthy clusters

  1. NEAR-INFRARED IMAGING AND SPECTROSCOPIC SURVEY OF THE SOUTHERN REGION OF THE YOUNG OPEN CLUSTER NGC 2264

    SciTech Connect

    Marinas, Naibi; Lada, Elizabeth A.; Teixiera, Paula S.; Lada, Charles J.

    2013-08-01

    We have obtained JHK near-IR images and JH band low-resolution spectra of candidate members of the southern region of the young open cluster NGC 2264. We have determined spectral types from H-band spectra for 54 sources, 25 of which are classified for the first time. The stars in our sample cover a large range of spectral types (A8-M8). Using a cluster distance of 780 pc, we determined a median age of 1 Myr for this region of NGC 2264, with 90% of the stars being 5 Myr or younger. To improve the statistical significance of our sample, we included 66 additional cluster members within our field of view with optical spectral classification in the literature. We derived infrared excesses using stellar properties to model the photospheric emission for each source and the extinction to correct FLAMINGOS near-IR and Spitzer mid-IR photometry, and obtained a disk fraction of 51% {+-} 5% for the region. Binning the stars by stellar mass, we find a disk fraction of 38% {+-} 9% for the 0.1-0.3 solar mass group, 55% {+-} 6% for 0.3-1 solar masses, and 58% {+-} 10% for the higher than 1 solar mass group. The lower disk fraction for the lower mass stars is similar to the results found in non-cluster regions like Taurus and Chamaeleon, but differs from the older 3 Myr cluster IC 348 in which the disk fraction is lower for the higher mass stars. This mass-dependent disk fraction is accentuated in the sample with isochrone ages younger than 2 Myr. Here, we find that 45% {+-} 11% of the 0.1-0.3 solar mass stars have disks, 60% {+-} 7% of the 0.3-1 solar mass stars have disks, and all 1-3 solar mass stars have disks. Stellar masses might be an important factor in the ability of a system to form or retain a disk early on. However, regardless of the stellar mass, the large infrared excesses expected from optically thick disks disappear within the first 2 Myr for all stars in our study and small excesses from optically thin disks are found mostly in sources younger than 4 Myr.

  2. Near-infrared Imaging and Spectroscopic Survey of the Southern Region of the Young Open Cluster NGC 2264

    NASA Astrophysics Data System (ADS)

    Mariñas, Naibí; Lada, Elizabeth A.; Teixeira, Paula S.; Lada, Charles J.

    2013-08-01

    We have obtained JHK near-IR images and JH band low-resolution spectra of candidate members of the southern region of the young open cluster NGC 2264. We have determined spectral types from H-band spectra for 54 sources, 25 of which are classified for the first time. The stars in our sample cover a large range of spectral types (A8-M8). Using a cluster distance of 780 pc, we determined a median age of 1 Myr for this region of NGC 2264, with 90% of the stars being 5 Myr or younger. To improve the statistical significance of our sample, we included 66 additional cluster members within our field of view with optical spectral classification in the literature. We derived infrared excesses using stellar properties to model the photospheric emission for each source and the extinction to correct FLAMINGOS near-IR and Spitzer mid-IR photometry, and obtained a disk fraction of 51% ± 5% for the region. Binning the stars by stellar mass, we find a disk fraction of 38% ± 9% for the 0.1-0.3 solar mass group, 55% ± 6% for 0.3-1 solar masses, and 58% ± 10% for the higher than 1 solar mass group. The lower disk fraction for the lower mass stars is similar to the results found in non-cluster regions like Taurus and Chamaeleon, but differs from the older 3 Myr cluster IC 348 in which the disk fraction is lower for the higher mass stars. This mass-dependent disk fraction is accentuated in the sample with isochrone ages younger than 2 Myr. Here, we find that 45% ± 11% of the 0.1-0.3 solar mass stars have disks, 60% ± 7% of the 0.3-1 solar mass stars have disks, and all 1-3 solar mass stars have disks. Stellar masses might be an important factor in the ability of a system to form or retain a disk early on. However, regardless of the stellar mass, the large infrared excesses expected from optically thick disks disappear within the first 2 Myr for all stars in our study and small excesses from optically thin disks are found mostly in sources younger than 4 Myr. Based on observations

  3. Designing of the Information Advising System to Assess the Potential of Creation and Development of Cluster Agglomeration in the Industrial Complex of the Region

    NASA Astrophysics Data System (ADS)

    Averchenkova, E. E.; Averchenkov, A. V.; Kulagina, N. A.

    2017-01-01

    The theoretical aspects of creation of the information advising system to assess the potential of development of the cluster agglomeration are described in this article. The algorithm provided in the article estimates possibilities of creation and development of the regional industrial cluster agglomeration. This article describes the possible use of the information advising system of the evaluation and diagnostic type in making managerial decisions by the participants of the technology innovation cluster.

  4. Spatial clusters of violent deaths in a newly urbanized region of Brazil: highlighting the social disparities

    PubMed Central

    2009-01-01

    Background Deaths due to homicides and traffic accidents among youth are a public health issue worldwide. Studies of the complex network of cause and effect on this topic point to both poverty and health inequalities. Different investigational approaches to intentional and unintentional deaths combined with socioeconomic variables can help create a better understanding of the association between violence and socioeconomic conditions. This study analyzed the spatial distribution and potential clusters of risk for intentional and unintentional deaths among youths aged 15-24 years in Goiânia, a newly urbanized city in central Brazil. Methods Death data and residential addresses were extracted from the national Mortality Information System and validated by household visits. To detect all potential cases, we prospectively investigated every death classified as a transport accident, assault, legal intervention, intentional self-harm, unknown underlying cause, and undetermined intent according to the ICD-10. The Geographical Information System was used to plot residential addresses, and cases were interactively geocoded to the residential address level using a digital map of the municipality. Spatial scan statistic was applied (Poisson model) to identify clusters of census tracts with high mortality due to intentional injuries and traffic accidents. The socioeconomic variables obtained using census data were compared between the most likely cluster and other areas of the municipality. Results The most violent deaths among young people were due to intentional injuries. Between August 2005 and August 2006, 145 addresses for cases of intentional injuries and traffic accidents were located and geocoded. No significant clusters for deaths due to traffic accidents were found within the municipality. One significant cluster (RR = 4.65; p = 0.029) composed of 14 cases of intentional deaths, mostly homicides, was detected in an emergent, populated, and very poor area on the

  5. Activation of a Silent Fungal Polyketide Biosynthesis Pathway through Regulatory Cross Talk with a Cryptic Nonribosomal Peptide Synthetase Gene Cluster ▿ †

    PubMed Central

    Bergmann, Sebastian; Funk, Alexander N.; Scherlach, Kirstin; Schroeckh, Volker; Shelest, Ekaterina; Horn, Uwe; Hertweck, Christian; Brakhage, Axel A.

    2010-01-01

    Filamentous fungi produce numerous natural products that constitute a consistent source of potential drug leads, yet it seems that the majority of natural products are overlooked since most biosynthesis gene clusters are silent under standard cultivation conditions. Screening secondary metabolite genes of the model fungus Aspergillus nidulans, we noted a silent gene cluster on chromosome II comprising two nonribosomal peptide synthetase (NRPS) genes, inpA and inpB, flanked by a regulatory gene that we named scpR for secondary metabolism cross-pathway regulator. The induced expression of the scpR gene using the promoter of the alcohol dehydrogenase AlcA led to the transcriptional activation of both the endogenous scpR gene and the NRPS genes. Surprisingly, metabolic profiling of the supernatant of mycelia overexpressing scpR revealed the production of the polyketide asperfuranone. Through transcriptome analysis we found that another silent secondary metabolite gene cluster located on chromosome VIII coding for asperfuranone biosynthesis was specifically induced. Quantitative reverse transcription-PCR proved the transcription not only of the corresponding polyketide synthase (PKS) biosynthesis genes, afoE and afoG, but also of their activator, afoA, under alcAp-scpR-inducing conditions. To exclude the possibility that the product of the inp cluster induced the asperfuranone gene cluster, a strain carrying a deletion of the NRPS gene inpB and, in addition, the alcAp-scpR overexpression cassette was generated. In this strain, under inducing conditions, transcripts of the biosynthesis genes of both the NRPS-containing gene cluster inp and the asperfuranone gene cluster except gene inpB were detected. Moreover, the existence of the polyketide product asperfuranone indicates that the transcription factor ScpR controls the expression of the asperfuranone biosynthesis gene cluster. This expression as well as the biosynthesis of asperfuranone was abolished after the deletion

  6. Photonuclear reaction as a probe for α -clustering nuclei in the quasi-deuteron region

    NASA Astrophysics Data System (ADS)

    Huang, B. S.; Ma, Y. G.; He, W. B.

    2017-03-01

    Photon-nuclear reaction in a transport model frame, namely an extended quantum molecular dynamics model, has been realized at the photon energy of 70-140 MeV in the quasi-deuteron regime. For an important application, we pay a special focus on photonuclear reactions of 12C(γ ,n p )10B where 12C is considered as different configurations including α clustering. Obvious differences for some observables have been observed among different configurations, which can be attributed to spatial-momentum correlation of a neutron-proton pair inside nucleus, and therefore it gives us a sensitive probe to distinguish the different configurations including α clustering with the help of the photonuclear reaction mechanism.

  7. Multiple large clusters of tuberculosis in London: a cross-sectional analysis of molecular and spatial data.

    PubMed

    Smith, Catherine M; Maguire, Helen; Anderson, Charlotte; Macdonald, Neil; Hayward, Andrew C

    2017-01-01

    Large outbreaks of tuberculosis (TB) represent a particular threat to disease control because they reflect multiple instances of active transmission. The extent to which long chains of transmission contribute to high TB incidence in London is unknown. We aimed to estimate the contribution of large clusters to the burden of TB in London and identify risk factors. We identified TB patients resident in London notified between 2010 and 2014, and used 24-locus mycobacterial interspersed repetitive units-variable number tandem repeat strain typing data to classify cases according to molecular cluster size. We used spatial scan statistics to test for spatial clustering and analysed risk factors through multinomial logistic regression. TB isolates from 7458 patients were included in the analysis. There were 20 large molecular clusters (with n>20 cases), comprising 795 (11%) of all cases; 18 (90%) large clusters exhibited significant spatial clustering. Cases in large clusters were more likely to be UK born (adjusted odds ratio 2.93, 95% CI 2.28-3.77), of black-Caribbean ethnicity (adjusted odds ratio 3.64, 95% CI 2.23-5.94) and have multiple social risk factors (adjusted odds ratio 3.75, 95% CI 1.96-7.16). Large clusters of cases contribute substantially to the burden of TB in London. Targeting interventions such as screening in deprived areas and social risk groups, including those of black ethnicities and born in the UK, should be a priority for reducing transmission.

  8. Multiple large clusters of tuberculosis in London: a cross-sectional analysis of molecular and spatial data

    PubMed Central

    Maguire, Helen; Anderson, Charlotte; Macdonald, Neil; Hayward, Andrew C.

    2017-01-01

    Large outbreaks of tuberculosis (TB) represent a particular threat to disease control because they reflect multiple instances of active transmission. The extent to which long chains of transmission contribute to high TB incidence in London is unknown. We aimed to estimate the contribution of large clusters to the burden of TB in London and identify risk factors. We identified TB patients resident in London notified between 2010 and 2014, and used 24-locus mycobacterial interspersed repetitive units–variable number tandem repeat strain typing data to classify cases according to molecular cluster size. We used spatial scan statistics to test for spatial clustering and analysed risk factors through multinomial logistic regression. TB isolates from 7458 patients were included in the analysis. There were 20 large molecular clusters (with n>20 cases), comprising 795 (11%) of all cases; 18 (90%) large clusters exhibited significant spatial clustering. Cases in large clusters were more likely to be UK born (adjusted odds ratio 2.93, 95% CI 2.28–3.77), of black-Caribbean ethnicity (adjusted odds ratio 3.64, 95% CI 2.23–5.94) and have multiple social risk factors (adjusted odds ratio 3.75, 95% CI 1.96–7.16). Large clusters of cases contribute substantially to the burden of TB in London. Targeting interventions such as screening in deprived areas and social risk groups, including those of black ethnicities and born in the UK, should be a priority for reducing transmission. PMID:28149918

  9. A Study of Cross-linked Regions of Poly(Vinyl Alcohol) Gels by Small-Angle Neutron Scattering

    NASA Astrophysics Data System (ADS)

    Lawrence, Mathias B.; Desa, J. A. E.; Aswal, V. K.

    2011-07-01

    A poly(vinyl alcohol)-borax cross-linked hydrogel has been studied by Small Angle Neutron Scattering as a function of borax concentration in the wave-vector transfer (Q) range of 0.017 Å-1 to 0.36 Å-1. It is found that as the concentration of borax increases, so does the intensity of scattering in this range. Beyond a borax concentration of 2 mg/ml, the increase in cross-linked PVA chains leads to cross-linked units larger than 150 Å as evidenced by a reduction in intensity in the lower Q region.

  10. Dynamic Trajectory Extraction from Stereo Vision Using Fuzzy Clustering

    NASA Astrophysics Data System (ADS)

    Onishi, Masaki; Yoda, Ikushi

    In recent years, many human tracking researches have been proposed in order to analyze human dynamic trajectory. These researches are general technology applicable to various fields, such as customer purchase analysis in a shopping environment and safety control in a (railroad) crossing. In this paper, we present a new approach for tracking human positions by stereo image. We use the framework of two-stepped clustering with k-means method and fuzzy clustering to detect human regions. In the initial clustering, k-means method makes middle clusters from objective features extracted by stereo vision at high speed. In the last clustering, c-means fuzzy method cluster middle clusters based on attributes into human regions. Our proposed method can be correctly clustered by expressing ambiguity using fuzzy clustering, even when many people are close to each other. The validity of our technique was evaluated with the experiment of trajectories extraction of doctors and nurses in an emergency room of a hospital.

  11. Fluids confined in wedges and by edges: From cluster integrals to thermodynamic properties referred to different regions

    SciTech Connect

    Urrutia, Ignacio

    2015-06-28

    Recently, new insights into the relation between the geometry of the vessel that confines a fluid and its thermodynamic properties were traced through the study of cluster integrals for inhomogeneous fluids. In this work, I analyze the thermodynamic properties of fluids confined in wedges or by edges, emphasizing on the question of the region to which these properties refer. In this context, the relations between the line-thermodynamic properties referred to different regions are derived as analytic functions of the dihedral angle α, for 0 < α < 2π, which enables a unified approach to both edges and wedges. As a simple application of these results, I analyze the properties of the confined gas in the low-density regime. Finally, using recent analytic results for the second cluster integral of the confined hard sphere fluid, the low density behavior of the line thermodynamic properties is analytically studied up to order two in the density for 0 < α < 2π and by adopting different reference regions.

  12. Fluids confined in wedges and by edges: From cluster integrals to thermodynamic properties referred to different regions.

    PubMed

    Urrutia, Ignacio

    2015-06-28

    Recently, new insights into the relation between the geometry of the vessel that confines a fluid and its thermodynamic properties were traced through the study of cluster integrals for inhomogeneous fluids. In this work, I analyze the thermodynamic properties of fluids confined in wedges or by edges, emphasizing on the question of the region to which these properties refer. In this context, the relations between the line-thermodynamic properties referred to different regions are derived as analytic functions of the dihedral angle α, for 0 < α < 2π, which enables a unified approach to both edges and wedges. As a simple application of these results, I analyze the properties of the confined gas in the low-density regime. Finally, using recent analytic results for the second cluster integral of the confined hard sphere fluid, the low density behavior of the line thermodynamic properties is analytically studied up to order two in the density for 0 < α < 2π and by adopting different reference regions.

  13. Clustering patterns of obesity-related multiple lifestyle behaviours and their associations with overweight and family environments: a cross-sectional study in Japanese preschool children

    PubMed Central

    Watanabe, Etsuko; Lee, Jung Su; Mori, Katsumi; Kawakubo, Kiyoshi

    2016-01-01

    Objectives The purpose of this study is (1) to identify obesity-related lifestyle behaviour patterns of diet, physical activity, sedentary and sleep behaviours in preschool children, (2) to examine the association between identified behaviour clusters and overweight/obesity and (3) to investigate differences in children's family environments according to clusters. Design setting and participants A cross-sectional study on 2114 preschool children aged 3–6 years who attended childcare facilities (24 nursery schools and 10 kindergartens) in Tsuruoka city, Japan in April 2003 was conducted. Main outcome measures Children's principal caregivers completed a questionnaire on children's lifestyle behaviours (dinner timing, outside playtime, screen time and night-time sleep duration), family environment (family members, maternal employment, mealtime regularity and parents' habitual exercise and screen time) and measurements of weight and height. Cluster analysis was performed using children's 4 lifestyle behaviours based on those non-missing values (n=1545). The χ2 tests and analysis of variance (ANOVA) estimated cluster differences in overweight/obesity and family environments. Results 6 clusters were identified. Children's overweight/obesity varied across clusters (p=0.007). The cluster with the most screen time, shorter night-time sleep duration, average dinner timing and outside playtime had the highest overweight/obesity prevalence (15.1%), while the cluster with the least screen time, the longest sleep duration, the earliest dinner timing and average outside playtime had the lowest prevalence (4.0%). Family environments regarding mealtime regularity and both parents' screen time also significantly varied across clusters. The cluster having the highest overweight/obesity prevalence had the highest proportion of irregular mealtimes and the most screen time for both parents. Conclusions This study suggests that public health approaches to prevent children

  14. Genus Calliophis of Asiatic coral snakes: A deficiency of venom cross-reactivity and neutralization against seven regional elapid antivenoms.

    PubMed

    Tan, Choo Hock; Liew, Jia Lee; Tan, Kae Yi; Tan, Nget Hong

    2016-10-01

    Venoms of Calliophis bivirgata and Calliophis intestinalis exhibited moderate binding activities toward Neuro Bivalent Antivenom (Taiwan) but not the other six elapid monovalent or bivalent antivenoms available in the region. All antivenoms failed to neutralize C. bivirgata venom lethality in mice. The findings indicate the need to validate antivenom cross-reactivity with in vivo cross-neutralization, and imply that distinct antigens of Calliophis venoms should be incorporated in the production of a pan-regional poly-specific antivenom.

  15. Visualization of heterogeneity and regional grading of gliomas by multiple features using magnetic resonance-based clustered images

    PubMed Central

    Inano, Rika; Oishi, Naoya; Kunieda, Takeharu; Arakawa, Yoshiki; Kikuchi, Takayuki; Fukuyama, Hidenao; Miyamoto, Susumu

    2016-01-01

    Preoperative glioma grading is important for therapeutic strategies and influences prognosis. Intratumoral heterogeneity can cause an underestimation of grading because of the sampling error in biopsies. We developed a voxel-based unsupervised clustering method with multiple magnetic resonance imaging (MRI)-derived features using a self-organizing map followed by K-means. This method produced novel magnetic resonance-based clustered images (MRcIs) that enabled the visualization of glioma grades in 36 patients. The 12-class MRcIs revealed the highest classification performance for the prediction of glioma grading (area under the receiver operating characteristic curve = 0.928; 95% confidential interval = 0.920–0.936). Furthermore, we also created 12-class MRcIs in four new patients using the previous data from the 36 patients as training data and obtained tissue sections of the classes 11 and 12, which were significantly higher in high-grade gliomas (HGGs), and those of classes 4, 5 and 9, which were not significantly different between HGGs and low-grade gliomas (LGGs), according to a MRcI-based navigational system. The tissues of classes 11 and 12 showed features of malignant glioma, whereas those of classes 4, 5 and 9 showed LGGs without anaplastic features. These results suggest that the proposed voxel-based clustering method provides new insights into preoperative regional glioma grading. PMID:27456199

  16. Search for OB stars running away from young star clusters. II. The NGC 6357 star-forming region

    NASA Astrophysics Data System (ADS)

    Gvaramadze, V. V.; Kniazev, A. Y.; Kroupa, P.; Oh, S.

    2011-11-01

    Dynamical few-body encounters in the dense cores of young massive star clusters are responsible for the loss of a significant fraction of their massive stellar content. Some of the escaping (runaway) stars move through the ambient medium supersonically and can be revealed via detection of their bow shocks (visible in the infrared, optical or radio). In this paper, which is the second of a series of papers devoted to the search for OB stars running away from young ( ≲ several Myr) Galactic clusters and OB associations, we present the results of the search for bow shocks around the star-forming region NGC 6357. Using the archival data of the Midcourse Space Experiment (MSX) satellite and the Spitzer Space Telescope, and the preliminary data release of the Wide-Field Infrared Survey Explorer (WISE), we discovered seven bow shocks, whose geometry is consistent with the possibility that they are generated by stars expelled from the young (~1-2 Myr) star clusters, Pismis 24 and AH03 J1725-34.4, associated with NGC 6357. Two of the seven bow shocks are driven by the already known OB stars, HD 319881 and [N78] 34. Follow-up spectroscopy of three other bow-shock-producing stars showed that they are massive (O-type) stars as well, while the 2MASS photometry of the remaining two stars suggests that they could be B0 V stars, provided that both are located at the same distance as NGC 6357. Detection of numerous massive stars ejected from the very young clusters is consistent with the theoretical expectation that star clusters can effectively lose massive stars at the very beginning of their dynamical evolution (long before the second mechanism for production of runaway stars, based on a supernova explosion in a massive tight binary system, begins to operate) and lends strong support to the idea that probably all field OB stars have been dynamically ejected from their birth clusters. A by-product of our search for bow shocks around NGC 6357 is the detection of three circular

  17. Cardiomyopathy mutations reveal variable region of myosin converter as major element of cross-bridge compliance.

    PubMed

    Seebohm, B; Matinmehr, F; Köhler, J; Francino, A; Navarro-Lopéz, F; Perrot, A; Ozcelik, C; McKenna, W J; Brenner, B; Kraft, T

    2009-08-05

    The ability of myosin to generate motile forces is based on elastic distortion of a structural element of the actomyosin complex (cross-bridge) that allows strain to develop before filament sliding. Addressing the question, which part of the actomyosin complex experiences main elastic distortion, we suggested previously that the converter domain might be the most compliant region of the myosin head domain. Here we test this proposal by studying functional effects of naturally occurring missense mutations in the beta-myosin heavy chain, 723Arg --> Gly (R723G) and 736Ile --> Thr (I736T), in comparison to 719Arg --> Trp (R719W). All three mutations are associated with hypertrophic cardiomyopathy and are located in the converter region of the myosin head domain. We determined several mechanical parameters of single skinned slow fibers isolated from Musculus soleus biopsies of hypertrophic cardiomyopathy patients and healthy controls. Major findings of this study for mutation R723G were i), a >40% increase in fiber stiffness in rigor with a 2.9-fold increase in stiffness per myosin head (S( *)(rigor R723G) = 0.84 pN/nm S( *)(rigor WT) = 0.29 pN/nm); and ii), a significant increase in force per head (F( *)(10 degrees C), 1.99 pN vs. 1.49 pN = 1.3-fold increase; F( *)(20 degrees C), 2.56 pN vs. 1.92 pN = 1.3-fold increase) as well as stiffness per head during isometric steady-state contraction (S( *)(active10 degrees C), 0.52 pN/nm vs. 0.28 pN/nm = 1.9-fold increase). Similar changes were found for mutation R719W (2.6-fold increase in S( *)(rigor); 1.8-fold increase in F( *)(10 degrees C), 1.6-fold in F( *)(20 degrees C); twofold increase in S( *)(active10 degrees C)). Changes in active cross-bridge cycling kinetics could not account for the increase in force and active stiffness. For the above estimates the previously determined fraction of mutated myosin in the biopsies was taken into account. Data for wild-type myosin of slow soleus muscle fibers support previous

  18. Stars and Star Clusters: A Look at Intermediate-Mass Star-Forming Regions

    NASA Astrophysics Data System (ADS)

    Lundquist, Michael J.; Kobulnicky, Henry A.; Lau, Ryan M.

    2017-01-01

    Star-forming regions hosting intermediate-mass stars straddle the boundary separating the the low- and high-mass regimes. These intermediate-mass star-forming regions can be used to probe this transition from low- to high-mass star formation. Our team has assembled an all-sky catalog of 616 candidate intermediate-mass star forming regions (IMSFRs) selected by IRAS colors and refined by visual inspection of WISE imagery. We present here two outer-Galaxy star-forming regions, IRAS22451+6154 and IRAS23448+6010, that despite having similar IRAS colors and mid-infrared morphologies, have vastly different stellar content. We combine Gemini and IRTF NIR spectroscopy with WIYN and SOFIA imaging for a thorough look at the stellar content of these two regions.

  19. Gap winds and their effects on regional oceanography Part I: Cross Sound, Alaska

    NASA Astrophysics Data System (ADS)

    Ladd, Carol; Cheng, Wei

    2016-10-01

    Gap-wind events flowing from Cross Sound in the eastern Gulf of Alaska (GOA) were examined using QuikSCAT wind data. The average duration of an event is 3.6 days with the longest event recorded in the QuikSCAT dataset being 12 days. Daily offshore directed winds with speeds >10 m s-1 are more common during the winter months (October-March), averaging 20.0 days per year, and less common during the summer (April - September), averaging 2.8 days per year. Interannual variability in the frequency of gap-wind events is correlated with El Niño. During gap-wind events, the spatial scales of high off-shore directed winds (>10 m s-1) reach almost 200 km off-shore and 225 km along the shelf break, suggesting that the winds directly influence both the shelf (20-65 km wide) and the off-shore waters. A model experiment suggests that a gap-wind event can result in eddy formation and changes in circulation and water properties. Increased entrainment of water from below the mixed layer due to the gap-wind event implies that mixed-layer nitrate concentrations could increase on the order of 5-10 μmole/l, potentially enhancing primary production in the region. An accompanying paper discusses part II of our study (Ladd et al., 2016) focusing on gap-wind events in the western GOA around Kodiak Island.

  20. Toward Regional Clusters: Networking Events, Collaborative Research, and the Business Finder

    NASA Astrophysics Data System (ADS)

    Reichling, Tim; Moos, Benjamin; Rohde, Markus; Wulf, Volker

    Networks of regionally collocated organizations improve the competitiveness of their member companies. This is not only a result of lower transportation costs when delivering or purchasing physical goods but also other matters such as mutual trust or a higher diffusion of specialized knowledge among companies that have emerged as important aspects of regional networks. Even increased competition among collocated companies can lead to comparative advantages over externals as a result of an increased pressure for innovation. While the reasons why regional networks of companies offer comparative advantages has been widely investigated, the question arises as to how networks can be developed in terms of higher interconnectedness and deeper connections.

  1. Iridium Complexes and Clusters in Dealuminated Zeolite HY: Distribution between Crystalline and Impurity Amorphous Regions

    SciTech Connect

    Martinez-Macias, Claudia; Xu, Pinghong; Hwang, Son-Jong; Lu, Jing; Chen, Cong-Yan; Browning, Nigel D.; Gates, Bruce C.

    2014-07-08

    Dealuminated zeolite HY was used to support Ir(CO)2 complexes formed from Ir(CO)2(C5H7O2). Infrared and X-ray absorption spectra and atomic-resolution electron microscopy images identify these complexes, and the images and 27Al NMR spectra identify impurity amorphous regions in the zeolite where the iridium is more susceptible to aggregation than in the crystalline regions. The results indicate a significant stability limitation of metal in amorphous impurity regions of zeolites.

  2. Clustering of Pre-Main-Sequence Stars in the Orion, Ophiuchus, Chamaeleon, Vela, and Lupus Star-forming Regions

    NASA Astrophysics Data System (ADS)

    Nakajima, Yasushi; Tachihara, Kengo; Hanawa, Tomoyuki; Nakano, Makoto

    1998-04-01

    We study clustering of pre-main-sequence stars in the Orion, Ophiuchus, Chamaeleon, Vela, and Lupus star-forming regions. We calculate the average surface density of companions, Σ(θ), as a function of angular distance, θ, from each star. We employ the method developed by Larson in a 1995 study for the calculation. In most of the regions studied, the function can be fitted by two power laws (Σ ~ θγ) with a break as found by Larson for the Taurus star-forming region. The power index, γ, is smaller at small separations than at large separations. The power index at large separations shows significant variation from region to region (-0.8 < γ < -0.1), while the power index at small separations does not (γ ~ -2). The power index at large separations relates to the distribution of the nearest-neighbor distance. When the latter can be fitted by the Poisson distribution, the power index is close to 0. When the latter is broader than the Poisson distribution, the power index is negatively large. This correlation can be interpreted as the result of the variation in the surface density within the region. At large separations, the power-law fit may indicate star formation history in the region and not the spatial structure like the self-similar hierarchical, or fractal, one. Because of the velocity dispersion, stars move from their birthplaces, and the surface density of coeval stars decreases with their age. When a star-forming region contains several groups of stars with different ages, a power law may fit the average surface density of companions for it. The break of the power law is located around 0.01-0.1 pc. There is a clear correlation between the break position and the mean nearest-neighbor distance. The break position may reflect dispersal of newly formed stars.

  3. Resonance Region Cross-Section Data Advancements for Nuclear Criticality Safety Applications and ENDF/B-VII.1

    SciTech Connect

    Dunn, Michael E; Leal, Luiz C; Guber, Klaus H; Arbanas, Goran; Wiarda, Dorothea; Sayer, Royce O; Derrien, Herve; HARVEY, JACK

    2011-01-01

    ORNL has completed new resonance region cross-section evaluations with covariance data to support nuclear criticality safety applications. This paper summarizes some of the most recent cross-section evaluations that have been completed and will be made available to process into nuclear data libraries for use with radiation transport codes. Specifically, the paper summarizes the work that has been completed for {sup 35}Cl, {sup 37}Cl , {sup 50}Cr, {sup 52}Cr, {sup 53}Cr, {sup 54}Cr, {sup 39}K, {sup 41}K, {sup 19}F, {sup 55}Mn, {sup 58}Ni, {sup 60}Ni, {sup 235}U, {sup 238}U, and {sup 239}Pu. Many of the new cross-section evaluations are based on new differential data measurements in the resonance region. Furthermore, corresponding covariance data analyses have been performed in conjunction with the resonance evaluation effort thereby providing a consistent set of covariance data to complement the resonance region cross-section evaluations. As a result, the new cross-section evaluations with covariance data can be used to support sensitivity/uncertainty analyses for criticality safety applications.

  4. Longshore-drift dispersed, storm-generated cross-stratified sandstone from some Cretaceous shallow marine strata, Rocky Mountain region

    SciTech Connect

    Gustason, E.R. )

    1990-05-01

    Most Cretaceous shallow marine strata of the Rocky Mountain region are characterized by asymmetrical upward-coarsening and upward-thickening sequences. The strata typically contain similar lithofacies (i.e., normally graded planar parallel laminated claystone, siltstone, and sandstone; hummocky cross-stratified sandstone; symmetrical and asymmetrical ripple cross-lamination; and trough and planar tublar cross-stratified sandstone) and display an upward increase in the thickness and frequency of sharp-based sandstone beds that grade into amalgamated cross-stratified sandstone. Most workers agree that sharp-based sandstone beds and hummocky cross-stratified sandstone are storm generated. However, the origin of trough and planar tabular cross-stratified sandstone is controversial. Most workers interpret these sedimentary structures as deposited from either storm-generated traction currents or combined flow currents on the shelf, tide-generated traction currents, or tidally dispersed, storm-generated suspension clouds. Detailed analysis of three-dimensional outcrops has revealed several significant features of these sedimentary structures that indicate they may have been deposited by longshore drift dispersed, storm-generated suspension clouds. Sets of trough and planar cross-stratified sandstone form medium-scale discontinuous, irregularly shaped sand bodies, bound by erosional surfaces and composed of unidirectional dip-oriented cross strata. Individual cross stratum commonly have a sigmoidal shape, are bound by either reactivation surfaces or mudstone drapes, and contain normally graded concordant laminae. Top-set laminae, are truncated by the upper set boundary, whereas bottom-set laminae, become asymptotic to the lower set boundary and commonly are reworked and overlain by wave generated, ripple cross-lamination or mudstone drapes.

  5. The assembly and evolution of the outter regions of Brightest Cluster Galaxies as traced by the star light and globular clusters.

    NASA Astrophysics Data System (ADS)

    Laporte, Chervin Fabien Pierre

    2015-08-01

    In this talk I will present high-resolution cosmological zoom-in N-body simulations of the assembly of galaxy clusters focussed on the late assembly of the Brightest Cluster Galaxies (BCGs) and their globular clusters. At z=2 dark matter halos are populated with stellar components (and globular clusters) following the scaling relations of z=2 massive quiescent galaxies and their subsequent evolution is followed to the present-day. This leads to a significant build up of the outter envelope of BCGs through accretion and stripping of galaxies consistent with the observed surface brightness profiles of real objects strongly suggesting a dissipationless merger scenario for their assembly with little star formation involved. I will show how it is possible to also study the evolution of the red and blue globular cluster populations in BCGs under the dissipationless merger scenario. I will present predictions on their spatial distribution and kinematics in clusters and how these compare with observations of globular clusters in Virgo and also depend on the accretion history inside the galaxy clusters. Finally, I will also discuss how blue globular clusters in particular can be used to infer the past accretion history of BCGs by tracing low-surface brightness features of shredded galaxies in BCGs otherwise not recognisable/detectable in the light.

  6. Single-link cluster analysis of earthquake aftershocks: Decay laws and regional variations

    SciTech Connect

    Davis, S.D.; Frohlich, C. )

    1991-04-10

    Using single-link cluster analysis, the authors investigate how various properties of aftershock sequences depend on their tectonic regime and focal depth. For International Seismological Centre earthquakes of m{sub b}{ge}4.8, they find that earthquakes deeper than 70 km have the fewest and smallest aftershock sequences. Even after accounting for differences in detectability and maximum magnitude, they find that ridge-transform earthquakes have smaller aftershock sequences that shallow subduction zone earthquakes. Among different subduction zones, they find that zones with high moment release rates possess larger aftershock sequences. Comparing ridge-transform zones, they find those with slower spreading rates possess larger aftershock sequences. By transposing origin times of several different aftershock sequences as if all had main shocks occurring at time zero, they are able to study the properties of aftershock sequences which individually have too few aftershocks to study by other means. Secondary events determined by single-link cluster analysis follow a modified Omori's (power law) decay for time separations of 0.1 day to 20 days from the parent event, with p values ranging from 0.539 {plus minus} 0.022 (intermediate- and deep-focus earthquakes) to 0.928 {plus minus} 0.024 (ridge-transform earthquakes). They find that earthquake foreshocks and multiplets also follow a modified Omori's law. At greater times from the main shock the decay is steeper than a power law decay, more like an exponential decay. Aftershocks in the Adak catalog (m{sub b}{ge}2.0) show a marked decrease in activity between 40 and 50 km depth. They speculate that the observed differences in number of aftershocks and p values may be caused by variations in fault heterogeneity or in fluid pressures.

  7. TECHNIQUES TO ASSESS CROSS-BORDER AIR POLLUTION AND APPLICATION TO A U.S.-MEXICO BORDER REGION

    EPA Science Inventory

    A year-long assessment of cross-border air pollution was conducted in the eastmost section of the US-Mexico border region, known as the Lower Rio Grande Valley, in South Texas. Measurements were conducted on the US side and included fine particle mass (PM2.5) and elemental com...

  8. Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemistry in the region of Iriduim and Gold

    SciTech Connect

    Hoffman, R D; Dietrich, F S; Kelley, K; Escher, J; Bauer, R; Mustafa, M

    2008-02-26

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from osmium (Z = 76) to gold (Z = 79). Of particular interest are the cross sections on Ir and Au including reactions on isomeric targets.

  9. Clustering of health-related behaviors, health outcomes and demographics in Dutch adolescents: a cross-sectional study

    PubMed Central

    2013-01-01

    Background Recent studies show several health-related behaviors to cluster in adolescents. This has important implications for public health. Interrelated behaviors have been shown to be most effectively targeted by multimodal interventions addressing wider-ranging improvements in lifestyle instead of via separate interventions targeting individual behaviors. However, few previous studies have taken into account a broad, multi-disciplinary range of health-related behaviors and connected these behavioral patterns to health-related outcomes. This paper presents an analysis of the clustering of a broad range of health-related behaviors with relevant demographic factors and several health-related outcomes in adolescents. Methods Self-report questionnaire data were collected from a sample of 2,690 Dutch high school adolescents. Behavioral patterns were deducted via Principal Components Analysis. Subsequently a Two-Step Cluster Analysis was used to identify groups of adolescents with similar behavioral patterns and health-related outcomes. Results Four distinct behavioral patterns describe the analyzed individual behaviors: 1- risk-prone behavior, 2- bully behavior, 3- problematic screen time use, and 4- sedentary behavior. Subsequent cluster analysis identified four clusters of adolescents. Multi-problem behavior was associated with problematic physical and psychosocial health outcomes, as opposed to those exerting relatively few unhealthy behaviors. These associations were relatively independent of demographics such as ethnicity, gender and socio-economic status. Conclusions The results show that health-related behaviors tend to cluster, indicating that specific behavioral patterns underlie individual health behaviors. In addition, specific patterns of health-related behaviors were associated with specific health outcomes and demographic factors. In general, unhealthy behavior on account of multiple health-related behaviors was associated with both poor psychosocial

  10. Geographical clustering of Trypanosoma cruzi I groups from Colombia revealed by low-stringency single specific primer-PCR of the intergenic regions of spliced-leader genes.

    PubMed

    Mejía-Jaramillo, Ana María; Arboleda-Sánchez, Sair; Rodríguez, Ingrid Bibiana; Cura, Carolina; Salazar, Alexander; Del Mazo, Jesús; Triana-Chávez, Omar; Schijman, Alejandro Gabriel

    2009-01-01

    A low-stringency single-primer polymerase chain reaction (LSSP-PCR) typing procedure targeted to the intergenic regions of spliced-leader genes (SL) was designed to profile Trypanosoma cruzi I stocks from endemic regions of Colombia. Comparison between SL-LSSP-PCR profiles of parasite DNA from vector faeces and cultures isolated from those faeces showed more conservative signatures than profiles using LSSP-PCR targeted to the minicircle variable regions (kDNA). This was also observed by analysing 15 parasite clones from one stock as well as serial samples of a same stock after in vitro culturing or inoculation into mice. Thus, SL-LSSP-PCR appears more appropriate than kDNA-LSSP-PCR for reliable typing of major T. cruzi I groups from in vitro cultured stocks and triatomine faeces. SL-LSSP-PCR grouped 46 of 47 T. cruzi I Colombian stocks according to their geographical procedences in four clusters: Cluster Cas from Casanare Department, Cluster Mg from Northern Magdalena department, Cluster Mom from Momposina Depression in Southern Magdalena and finally Cluster NW from northwestern Colombia, including Sucre, Chocó, Córdoba and Antioquia departments. Sequence analysis identified punctual mutations among amplicons from each cluster. Within Cluster Mg, sequence polymorphism allowed association with different sylvatic vector species. Novel SL sequences and LSSP-PCR profiles are reported from T. cruzi I infecting Eratyrus cuspidatus, Panstrongylus geniculatus and Rhodnius pallescens vectors.

  11. STAR-FORMING REGION Sh 2-233IR. I. DEEP NEAR-INFRARED OBSERVATIONS TOWARD THE EMBEDDED STELLAR CLUSTERS

    SciTech Connect

    Yan, Chi-Hung; Wang, Shiang-Yu; Su, Yu-Nang; Minh, Y. C.; Ginsburg, Adam

    2010-09-01

    We observed the Sh 2-233IR (S233IR) region with better sensitivity in the near-infrared than in previous studies of this region. By applying statistical subtraction of the background stars, we identified member sources and derived the age and mass of three distinguishable sub-groups in this region: Sh 2-233IR NE, Sh 2-233IR SW, and the 'distributed stars' over the whole cloud. Star formation may occur sequentially with a relatively small age difference ({approx}0.2-0.3 Myr) between subclusters. We found that the slopes for the initial mass function ({Gamma} {approx} -0.5) of two subclusters are flatter than those of Salpeter, which suggests that more massive stars were preferentially formed in those clusters compared to other Galactic star-forming regions. These subclusters may not result from the overall collapse of the whole cloud, but have formed by triggering before the previous star formation activities disturbed the natal molecular cloud. Additionally, high star formation efficiency ({approx}>40%) of the subclusters may also suggest that stars form very efficiently in the center of the northeast.

  12. Beta-globin gene cluster haplotypes in Afro-Uruguayans from two geographical regions (South and North).

    PubMed

    Da Luz, Julio; Kimura, Elza Miyuki; Costa, Fernando Ferreira; Sonati, Maria de Fatima; Sans, Mónica

    2010-01-01

    The beta-globin gene cluster haplotypes were identified in 52 and 40 chromosomes from two Afro-Uruguayan populations located in the South and North of the country, respectively. In both regions, the 5' haplotype 2 (+ - - - -), characteristic of non-African populations, was the most frequent, reflecting a strong process of admixture in Afro-Uruguayans (0.355 and 0.262, respectively). The haplotypes 3 (- - - - +) and 4 (- + - - +), characteristics of African sub-Saharan populations, present inverse frequencies in North and South: whereas in the South haplotype 3 is the second most frequent (0.232), and haplotype 4 presents a low frequency (0.019), in the North haplotype 4 is the third most frequent (0.140), and haplotype 3 only reaches an intermediate frequency (0.088). The pairwise F(ST) and the exact test of differentiation show genetic heterogeneity between both regions. Nei's genetic distance show that South and North present affinities with Bantu groups, although the North present the smallest genetic distance with the Mandenka, a Senegalese population. With respect to 3' haplotypes, haplotype I was the most frequent in both populations, followed by haplotype II, characteristic of sub-Saharan Africans. The high frequencies of haplotype III-Asian could indicate admixture with Native American populations. The differences observed between both Uruguayan regions could be explained by microevolutionary events as genetic drift, founder effects, differential admixture, and/or distinct origin of the African slaves introduced in those regions.

  13. "Replicated" genome wide association for dependence on illegal substances: genomic regions identified by overlapping clusters of nominally positive SNPs.

    PubMed

    Drgon, Tomas; Johnson, Catherine A; Nino, Michelle; Drgonova, Jana; Walther, Donna M; Uhl, George R

    2011-03-01

    Declaring "replication" from results of genome wide association (GWA) studies is straightforward when major gene effects provide genome-wide significance for association of the same allele of the same SNP in each of multiple independent samples. However, such unambiguous replication may be unlikely when phenotypes display polygenic genetic architecture, allelic heterogeneity, locus heterogeneity, and when different samples display linkage disequilibria with different fine structures. We seek chromosomal regions that are tagged by clustered SNPs that display nominally significant association in each of several independent samples. This approach provides one "nontemplate" approach to identifying overall replication of groups of GWA results in the face of difficult genetic architectures. We apply this strategy to 1 million (1M) SNP Affymetrix and Illumina GWA results for dependence on illegal substances. This approach provides high confidence in rejecting the null hypothesis that chance alone accounts for the extent to which clustered, nominally significant SNPs from samples of the same racial/ethnic background identify the same chromosomal regions. There is more modest confidence in: (a) identification of individual chromosomal regions and genes and (b) overlap between results from samples of different racial/ethnic backgrounds. The strong overlap identified among the samples with similar racial/ethnic backgrounds, together with prior work that identified overlapping results in samples of different racial/ethnic backgrounds, support contributions to individual differences in vulnerability to addictions that come from both relatively older allelic variants that are common in many current human populations and newer allelic variants that are common in fewer current human populations.

  14. Integral cross sections for π-p interaction in the 3,3 resonance region

    NASA Astrophysics Data System (ADS)

    Friedman, E.; Paul, M.; Schechter, M.; Altman, A.; Jennings, B. K.; Wagner, G. J.; Fazel, N.; Johnson, R. R.; Suen, N.; Fraenkel, Z.

    1993-03-01

    Total cross sections for the π-p single charge exchange and 20° “partial-total” cross sections have been measured between 126 and 202 MeV pion energy. The former are about 4% below similar results of Bugg et al. and (5-10)% below predictions made with currently accepted phase shifts. The latter agree quite well with calculations.

  15. 75 FR 16739 - EDA Participation in the Energy Efficient Building Systems Regional Innovation Cluster Initiative

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-02

    ... Economic Development Administration EDA Participation in the Energy Efficient Building Systems Regional.... ACTION: Notice and request for applications. SUMMARY: EDA announces its participation in the Energy.... The Taskforce has selected Energy Efficient Building Systems Design as the topical focus for its...

  16. Hubble Space Telescope photometry of the central regions of Virgo cluster elliptical galaxies. 3: Brightness profiles

    NASA Astrophysics Data System (ADS)

    Ferrarese, L.; van den Bosch, F. C.; Ford, H. C.; Jaffe, W.; O'Connell, R. W.

    1994-11-01

    We have used the Planetary Camera on the Hubble Space Telescope (HST) to study the morphology and surface brightness parameters of a luminosity-limited sample of fourteen elliptical galaxies in the Virgo cluster. The total apparent blue magnitudes of the galaxies range between 9.4 and 13.4. In this paper, the core brightness profiles are presented, while the overall morphology and the isophotal shapes are discussed in two companion papers (Jaffe et al. (1994); van den Bosch et al. (1994)). We show that, in spite of the spherical aberration affecting the HST primary mirror, deconvolution techniques allow recovery of the brightness profile up to 0.2 arcsec from the center of the galaxies. We find that none of the galaxies has an isothermal core. On the basis of their morphological and photometrical properties, the galaxies can be divided in two physically distinct groups, referred to as Type I and Type II. All of the Type I galaxies are classified as E1 to E3 in the Revised Shapley Ames Catalog (Sandage & Tammann 1981), while Type II galaxies are classified as E5 to E7. The characteristics of Type II galaxies are explained by the presence of disks component on both the 1 arcsec and the 10 arcsec scales, while Type I galaxies correspond to the classical disk-free ellipticals.

  17. Hubble Space Telescope photometry of the central regions of Virgo cluster elliptical galaxies. 3: Brightness profiles

    NASA Technical Reports Server (NTRS)

    Ferrarese, Laura; Bosch, Frank C. Van Den; Ford, Holland C.; Jaffe, Walter; O'Connell, Robert W.

    1994-01-01

    We have used the Planetary Camera on the Hubble Space Telescope (HST) to study the morphology and surface brightness parameters of a luminosity-limited sample of fourteen elliptical galaxies in the Virgo cluster. The total apparent blue magnitudes of the galaxies range between 9.4 and 13.4. In this paper, the core brightness profiles are presented, while the overall morphology and the isophotal shapes are discussed in two companion papers (Jaffe et al. (1994); van den Bosch et al. (1994)). We show that, in spite of the spherical aberration affecting the HST primary mirror, deconvolution techniques allow recovery of the brightness profile up to 0.2 arcsec from the center of the galaxies. We find that none of the galaxies has an isothermal core. On the basis of their morphological and photometrical properties, the galaxies can be divided in two physically distinct groups, referred to as Type I and Type II. All of the Type I galaxies are classified as E1 to E3 in the Revised Shapley Ames Catalog (Sandage & Tammann 1981), while Type II galaxies are classified as E5 to E7. The characteristics of Type II galaxies are explained by the presence of disks component on both the 1 arcsec and the 10 arcsec scales, while Type I galaxies correspond to the classical disk-free ellipticals.

  18. Holocene coastal notches in the Mediterranean region: Indicators of palaeoseismic clustering?

    NASA Astrophysics Data System (ADS)

    Boulton, S. J.; Stewart, I. S.

    2015-05-01

    Marine tidal notches are developed by bioerosion in the intertidal zones of rocky coasts, but a combination of sea-level change and crustal movements can result in them being raised above or submerged below the water line. For that reason, the present-day elevation of these former shorelines relative to the mean sea level has long been used to quantify relative coastal uplift and subsidence in tectonically active areas, assuming that the sea-level (eustatic) change component is known. Along the microtidal Mediterranean littoral, it is generally assumed that notches develop during relative stillstands of sea level, when tectonic and eustatic trends are in unison, and that discrete notch levels record abrupt shoreline changes caused by local seismic displacements. Recently, however, a climatic model for notch formation has been proposed, in which stable periods of Holocene climate favour enhanced erosion; in this competing model, the rate of sea-level rise is lower than the tectonic uplift rate and individual notches are not specific seismic indicators. Because marine notches are widely used as geomorphic markers of tectonic, and in some cases palaeoseismic, movements, a reappraisal of the geological significance of these strandlines is warranted. In this paper, we explore the two conflicting notch models using a database of Eastern Mediterranean palaeoshorelines. Although we conclude that the spatial and temporal distribution of the notches supports a dominantly tectonic control on notch genesis as a result of earthquake clustering, we highlight how the diachronous timing of notch development tempers their value as tectonic markers.

  19. Clustering of Risk Behaviors and their Social Determinants among Primary School Learners in Beijing, China: A Cross-sectional Study

    PubMed Central

    Zhang, Yan; Ji, Ying

    2015-01-01

    Background: Studies in developed countries reveal that poor lifestyle choices triggering diseases typically cluster among children. However, there is insufficient evidence on the clustering of risk behaviors among children in developing countries. This study aimed to determine the clustering of risk behaviors and their social determinants among 4th-and 5th -grade learners in Beijing, China. Methods: The sample comprised of 967 learners from six primary schools enrolled migrant and resident learners by two-stage stratified cluster sampling. Prevalence denoted the risk behaviors and their clustering. A log-linear model was used to explore the clustering patterns. Ordinal logistic regression determined the influence of demographic characteristics, school environment, and family context on behavioral clustering. Results: The prevalence of none, one, two, and three or more risk factors was 61.2%, 20.0%, 10.8%, and 8.1% for infectious diseases and 46.0%, 30.6%, 15.4%, and 8.0% for chronic diseases, respectively. Some behaviors appeared dependent and were more likely to be observed together. The three most influential factors for infectious diseases were school type (odds ratio [OR] =4.47, 95% confidence interval [CI] 3.00–6.66), school located in an inner suburb (OR = 0.27, 95% CI 0.18–0.38), and gender (OR = 0.56, 95% CI 0.42–0.74). Regarding risk behaviors for chronic diseases, clustering was not associated with household registration status and number of appliances, but was significantly associated with school type (OR = 5.36, 95% CI 3.72–7.73), school located in an inner suburb (OR = 0.59, 95% CI 0.43–0.81), and gender (OR = 0.61, 95% CI 0.47–0.78). School environment variables were the most significant contributor to the number of risk behaviors. Conclusions: The characteristics of schools enrolling migrants and residents influenced the number of risk behaviors. Therefore, improved school conditions and integrated behavioral interventions are

  20. Level crossings and zero-field splitting in the {Cr8}-cubane spin-cluster studied using inelastic neutron scattering and magnetization

    SciTech Connect

    Vaknin, D.; Garlea, Vasile O; Demmel, F.; Mamontov, Eugene; Nojiri, H; Martin, Catalin; Chiorescu, Irinel; Qiu, Y.; Luban, M.; Kogerler, P.; Fielden, J.; Engelhardt, L; Rainey, C

    2010-01-01

    Inelastic neutron scattering (INS) in variable magnetic field and high-field magnetization measurements in the millikelvin temperature range were performed to gain insight into the low-energy magnetic excitation spectrum and the field-induced level crossings in the molecular spin cluster {Cr8}-cubane. These complementary techniques provide consistent estimates of the lowest level-crossing field. The overall features of the experimental data are explained using an isotropic Heisenberg model, based on three distinct exchange interactions linking the eight CrIII paramagnetic centers (spins s = 3/2), that is supplemented with a relatively large molecular magnetic anisotropy term for the lowest S = 1 multiplet. It is noted that the existence of the anisotropy is clearly evident from the magnetic field dependence of the excitations in the INS measurements, while the magnetization measurements are not sensitive to its effects.

  1. Level crossings and zero-field splitting in the {Cr8}-cubane spin cluster studied using inelastic neutron scattering and magnetization.

    PubMed

    Vaknin, D; Garlea, V O; Demmel, F; Mamontov, E; Nojiri, H; Martin, C; Chiorescu, I; Qiu, Y; Kögerler, P; Fielden, J; Engelhardt, L; Rainey, C; Luban, M

    2010-11-24

    Inelastic neutron scattering (INS) in variable magnetic field and high-field magnetization measurements in the millikelvin temperature range were performed to gain insight into the low-energy magnetic excitation spectrum and the field-induced level crossings in the molecular spin cluster {Cr(8)}-cubane. These complementary techniques provide consistent estimates of the lowest level-crossing field. The overall features of the experimental data are explained using an isotropic Heisenberg model, based on three distinct exchange interactions linking the eight Cr(III) paramagnetic centers (spins s = 3/2), that is supplemented with a relatively large molecular magnetic anisotropy term for the lowest S = 1 multiplet. It is noted that the existence of the anisotropy is clearly evident from the magnetic field dependence of the excitations in the INS measurements, while the magnetization measurements are not sensitive to its effects.

  2. THE HIGH-VELOCITY MOLECULAR OUTFLOWS IN MASSIVE CLUSTER-FORMING REGION G10.6-0.4

    SciTech Connect

    Liu Hauyu Baobab; Ho, Paul T. P.; Zhang Qizhou E-mail: pho@asiaa.sinica.edu.t

    2010-12-20

    We report the arcsecond resolution Submillimeter Array observations of the {sup 12}CO (2-1) transition in the massive cluster-forming region G10.6-0.4. In these observations, the high-velocity {sup 12}CO emission is resolved into individual outflow systems, which have a typical size scale of a few arcseconds. These molecular outflows are energetic and are interacting with the ambient molecular gas. By inspecting the shock signatures traced by CH{sub 3}OH, SiO, and HCN emissions, we suggest that abundant star formation activities are distributed over the entire 0.5 pc scale dense molecular envelope. The star formation efficiency over one global free-fall timescale (of the 0.5 pc molecular envelope, {approx}10{sup 5} years) is about a few percent. The total energy feedback of these high-velocity outflows is higher than 10{sup 47} erg, which is comparable to the total kinetic energy in the rotational motion of the dense molecular envelope. From order-of-magnitude estimations, we suggest that the energy injected from the protostellar outflows is capable of balancing the turbulent energy dissipation. No high-velocity bipolar molecular outflow associated with the central OB cluster is directly detected, which can be due to the photoionization.

  3. Cluster analysis of Landslide Vulnerable region on an urban Area in South Korea

    NASA Astrophysics Data System (ADS)

    Moon, Yonghee; Lee, Sangeun; Kim, Myoungsoo; Baek, Jongrak

    2016-04-01

    Mountain areas occupy about 65% of the territory in South Korea. Due to the rapid population growth and urbanization, many cities suffer from the limitation in space, and hence the commercial buildings, educational facilities, and housing settlement areas continue to stretch until the bottom of the mountain. In result, residents become more and more vulnerable to landslides and debris flow. This led to the central government to perceiving the need for strengthening regulations relevant to urban planning. In order to consider risks due to landslides and debris flow in the stage of urban planning, present authors suggested the strategies, including: first, selecting priority areas necessary to manage landslide-related disasters strictly; second, establishing the integrated management system useful to offer technical assistances to persons in charge of urban planning in the areas; third, promoting disaster awareness programs with those persons along with the central government. As the first attempt, this study mainly discusses the GIS-application procedures in which authors selected the priority areas, which are summarized: 1. Collect the landslide historical data for the period 1999 - 2012 when the disasters particularly threatened the whole country. 2. Define the areas with the one-kilometer radius around the landslide occurrence places. 3. Exclude the areas where population is less than 100 persons per 1 km2. 4. Exclude the areas where mountains with Grade I or II of landslide risk (announced by the Korea Forest Service) go below a certain portion of the area. 5. Carry out the cluster analysis with the remaining areas 6. Classify the types at the standpoint of landslide disaster risk management. Through the procedures, this study obtained a total of 86 priority areas, which were also classified into 24 areas - Type A (high population exposure and mid landslide occurrence likelihood) -, 25 areas - Type B (mid population exposure and high landslide occurrence

  4. [Profile distribution of soil aggregates organic carbon in primary forests in Karst cluster-peak depression region].

    PubMed

    Lu, Ling-Xiao; Song, Tong-Qing; Peng, Wan-Xia; Zeng, Fu-Ping; Wang, Ke-Lin; Xu, Yun-Lei; Yu, Zi; Liu, Yan

    2012-05-01

    Soil profiles were collected from three primary forests (Itoa orientalis, Platycladus orientalis, and Radermachera sinica) in Karst cluster-peak depression region to study the composition of soil aggregates, their organic carbon contents, and the profile distribution of the organic carbon. In the three forests, >2 mm soil aggregates were dominant, occupying about 76% of the total. The content of soil total organic carbon ranged from 12.73 to 68.66 g x kg(-1), with a significant difference among the forests. The organic carbon content in <1 mm soil aggregates was slightly higher than that in >2 mm soil aggregates, but most of soil organic carbon was stored in the soil aggregates with greater particle sizes. About 70% of soil organic carbon came from >2 mm soil aggregates. There was a significant positive relationship between the contents of 2-5 and 5-8 mm soil aggregates and the content of soil organic carbon. To increase the contents of 2-8 mm soil aggregates could effectively improve the soil carbon sequestration in Karst region. In Itoa orientalis forest, 2-8 mm soil aggregates accounted for 46% of the total, and the content of soil total organic carbon reached to 37.62 g x kg(-1), which implied that Itoa orientalis could be the suitable tree species for the ecological restoration in Karst region.

  5. Malaria Prevalence, Spatial Clustering and Risk Factors in a Low Endemic Area of Eastern Rwanda: A Cross Sectional Study

    PubMed Central

    Bizimana, Jean Pierre; Agaba, Steven; Dukuzumuremyi, Javier; Baas, Lisette; de Dieu Harelimana, Jean; Mens, Petra F.; Boer, Kimberly R.; de Vries, Peter J.

    2013-01-01

    Background Rwanda reported significant reductions in malaria burden following scale up of control intervention from 2005 to 2010. This study sought to; measure malaria prevalence, describe spatial malaria clustering and investigate for malaria risk factors among health-centre-presumed malaria cases and their household members in Eastern Rwanda. Methods A two-stage health centre and household-based survey was conducted in Ruhuha sector, Eastern Rwanda from April to October 2011. At the health centre, data, including malaria diagnosis and individual level malaria risk factors, was collected. At households of these Index cases, a follow-up survey, including malaria screening for all household members and collecting household level malaria risk factor data, was conducted. Results Malaria prevalence among health centre attendees was 22.8%. At the household level, 90 households (out of 520) had at least one malaria-infected member and the overall malaria prevalence for the 2634 household members screened was 5.1%. Among health centre attendees, the age group 5–15 years was significantly associated with an increased malaria risk and a reported ownership of ≥4 bednets was significantly associated with a reduced malaria risk. At the household level, age groups 5–15 and >15 years and being associated with a malaria positive index case were associated with an increased malaria risk, while an observed ownership of ≥4 bednets was associated with a malaria risk-protective effect. Significant spatial malaria clustering among household cases with clusters located close to water- based agro-ecosystems was observed. Conclusions Malaria prevalence was significantly higher among health centre attendees and their household members in an area with significant household spatial malaria clustering. Circle surveillance involving passive case finding at health centres and proactive case detection in households can be a powerful tool for identifying household level malaria burden

  6. Product PCNPsurv or the "reduced" evaporation residue cross section σER/σfusion for "hot" fusion reactions studied with the dynamical cluster-decay model

    NASA Astrophysics Data System (ADS)

    Chopra, Sahila; Kaur, Arshdeep; Hemdeep, Gupta, Raj K.

    2016-04-01

    The product PCNPsurv of compound nucleus (CN) fusion probability PCN and survival probability Psurv is calculated to determine the reduced evaporation residue cross section σER/σfusion , denoted σERreduced, with (total) fusion cross section σfusion given as a sum of CN-formation cross section σCN and non-CN cross section σnCN for each reaction, where σCN is the sum of evaporation residue cross section σER and fusion-fission cross section σff and σnCN, if not measured, is estimated empirically as the difference between measured and calculated σfusion. Our calculations of PCN and Psurv, based on the dynamical cluster-decay model, were successfully made for some 17 "hot" fusion reactions, forming different CN of mass numbers ACN˜100 -300 , with deformations of nuclei up to hexadecapole deformations and "compact" orientations for both coplanar (Φc=0∘ ) and noncoplanar (Φc≠0∘ ) configurations, using various different nuclear interaction potentials. Interesting variations of σERreduced with CN excitation energy E*, fissility parameter χ , CN mass ACN, and Coulomb parameter Z1Z2 show that, independent of entrance channel, different isotopes of CN, and nuclear interaction potentials used, the dominant quantity in the product is Psurv, which classifies all the studied CN into three groups of weakly fissioning, radioactive, and strongly fissioning superheavy nuclei, with relative magnitudes of σERreduced˜1 , ˜10-6 , and ˜10-11 , which, like for PCN, get further grouped in two dependencies of (i) weakly fissioning and strongly fissioning superheavy nuclei decreasing with increasing E* and (ii) radioactive nuclei increasing with increasing E*.

  7. Absolute Rayleigh scattering cross sections of gases and freons of stratospheric interest in the visible and ultraviolet regions

    NASA Technical Reports Server (NTRS)

    SHARDANAND; Rao, A. D. P.

    1977-01-01

    The laboratory measurements of absolute Rayleigh scattering cross sections as a function wavelength are reported for gas molecules He, Ne, Ar, N2, H2, O2, CO2, CH4 and for vapors of most commonly used freons CCl2F2, CBrF3, CF4, and CHClf2. These cross sections are determined from the measurements of photon scattering at an angle of 54 deg 44 min which yield the absolute values independent of the value of normal depolarization ratios. The present results show that in the spectral range 6943-3638A deg, the values of the Rayleigh scattering cross section can be extrapolated from one wavelength to the other using 1/lambda (4) law without knowing the values of the polarizabilities. However, such an extrapolation can not be done in the region of shorter wavelengths.

  8. Electron Tomographic Analysis of Cytoskeletal Cross-Bridges in the Paranodal Region of the Node of Ranvier in Peripheral Nerves

    PubMed Central

    Perkins, Guy A.; Sosinsky, Gina E.; Ghassemzadeh, Sassan; Perez, Alex; Jones, Ying; Ellisman, Mark H.

    2008-01-01

    The node of Ranvier is a site for ionic conductances along myelinated nerves and governs the saltatory transmission of action potentials. Defects in the cross-bridging and spacing of the cytoskeleton is a prominent pathologic feature in diseases of the peripheral nerve. Electron tomography was used to examine cytoskeletal-cytoskeletal, membrane-cytoskeletal, and heterologous cell connections in the paranodal region of the node of Ranvier in peripheral nerves. Focal attachment of cytoskeletal filaments to each other and to the axolemma and paranodal membranes of the Schwann cell via narrow cross-bridges was visualized in both neuronal and glial cytoplasms. A subset of intermediate filaments associates with the cytoplasmic surfaces of supramolecular complexes of transmembrane structures that are presumed to include known and unknown junctional proteins. Mitochondria were linked to both microtubules and neurofilaments in the axoplasm and to neighboring smooth endoplasmic reticulum by narrow cross-bridges. Tubular cisternae in the glial cytoplasm were also linked to the paranodal glial cytoplasmic loop juxtanodal membrane by short cross-bridges. In the extracellular matrix between axon and Schwann cell, junctional bridges formed long cylinders inking the two membranes. Interactions between cytoskeleton, membranes, and extracellular matrix associations in the paranodal region is likely critical not only for scaffolding, but also for intracellular and extracellular communication. PMID:18096402

  9. Dental-to-velar perceptual assimilation: A cross-linguistic study of the perception of dental stop+/1/ clusters

    PubMed Central

    Hallé, Pierre A.; Best, Catherine T.

    2009-01-01

    French listeners perceive illegal /tl/ and /dl/ clusters as legal /kl/ and /gl/, suggesting that /dl, tl/ undergo “phonotactic perceptual assimilation” to the phonetically most similar permissible clusters [Hallé et al., J. Exp. Psychol. Hum. Percept. Perform. (1998)]. However, without a comparison to native speakers of a language allowing initial /tl, dl/, other explanations remain open (e.g., universal phonetic biases). Experiment 1 compared native French and Hebrew listeners on perception of Hebrew /tl/-/kl/ and /dl/-/gl/. On a language-specific phonotactics account, these contrasts should be difficult for listeners whose language disallows initial /tl, dl/ while allowing /kl, gl/(French), but not for listeners whose language permits all four clusters (Hebrew). Indeed, French but not Hebrew listeners showed difficulty discriminating /tl/-/kl/, and tended to categorize the initial consonant of /tl/ as /k/; analogous effects for /dl/-/gl/ were weaker. Experiment 2 tested speakers of American English, which also disallows initial /tl, dl/ but realizes stop-voicing differently than French or Hebrew, to examine possible contributions of language-specific phonetic settings. Their performance was similar to that of French listeners, though they had significantly greater difficulty with /dl-/gl/. The results support the proposal of language-specific phonotactic perceptual assimilation, with modest contributions from language-specific phonetic settings. PMID:17550188

  10. A point mutation in the [2Fe–2S] cluster binding region of the NAF-1 protein (H114C) dramatically hinders the cluster donor properties

    SciTech Connect

    Tamir, Sagi; Eisenberg-Domovich, Yael; Conlan, Andrea R.; Stofleth, Jason T.; Lipper, Colin H.; Paddock, Mark L.; Mittler, Ron; Jennings, Patricia A.; Livnah, Oded Nechushtai, Rachel

    2014-06-01

    NAF-1 has been shown to be related with human health and disease, is upregulated in epithelial breast cancer and suppression of its expression significantly suppresses tumor growth. It is shown that replacement of the single His ligand with Cys resulted in dramatic changes to the properties of its 2Fe-2S clusters without any global crystal structural changes. NAF-1 is an important [2Fe–2S] NEET protein associated with human health and disease. A mis-splicing mutation in NAF-1 results in Wolfram Syndrome type 2, a lethal childhood disease. Upregulation of NAF-1 is found in epithelial breast cancer cells, and suppression of NAF-1 expression by knockdown significantly suppresses tumor growth. Key to NAF-1 function is the NEET fold with its [2Fe–2S] cluster. In this work, the high-resolution structure of native NAF-1 was determined to 1.65 Å resolution (R factor = 13.5%) together with that of a mutant in which the single His ligand of its [2Fe–2S] cluster, His114, was replaced by Cys. The NAF-1 H114C mutant structure was determined to 1.58 Å resolution (R factor = 16.0%). All structural differences were localized to the cluster binding site. Compared with native NAF-1, the [2Fe–2S] clusters of the H114C mutant were found to (i) be 25-fold more stable, (ii) have a redox potential that is 300 mV more negative and (iii) have their cluster donation/transfer function abolished. Because no global structural differences were found between the mutant and the native (wild-type) NAF-1 proteins, yet significant functional differences exist between them, the NAF-1 H114C mutant is an excellent tool to decipher the underlying biological importance of the [2Fe–2S] cluster of NAF-1 in vivo.

  11. Motion of small cross-channel clusters on W(2 1 1) surface: A density functional theory study

    NASA Astrophysics Data System (ADS)

    Jurczyszyn, L.; Antczak, G.

    2014-04-01

    The adsorption and diffusion of cross-channel ad-dimers and ad-trimers was investigated using ab-initio DFT calculations. In contrast to in-channel dimers, the motion of cross-channel dimers proceeds one ad-atom at the time with an activation energy comparable to observed for quasi-isolated ad-atoms. The separation of ad-atoms by the surface channel wall lowers, but not eliminates, ad-atoms interactions. Pair interactions show long-range oscillatory behavior with an electronic origin. The short range interactions are modified by creation of straight and staggered direct bonds. Motion of ad-trimers proceeds in the same fashion as for cross-channel ad-dimers.

  12. Clustering of low usage codons in the translation initiation region of hepatitis C virus.

    PubMed

    Zhou, Jian-hua; Su, Jun-hong; Chen, Hao-tai; Zhang, Jie; Ma, Li-na; Ding, Yao-zhong; Stipkovits, Laszlo; Szathmary, Susan; Pejsak, Zygmunt; Liu, Yong-sheng

    2013-08-01

    The adaptation of the overall codon usage pattern of hepatitis C virus (HCV) to that of human is estimated by the synonymous codon usage value (RSCU). The synonymous codon usage biases for the translation initiation region (TIR) of this virus are also analyzed by calculation of usage fluctuation of each synonymous codon along the TIR (the first 30 codon sites of the whole coding sequence of HCV). As for the overall codon usage pattern of HCV, this virus has a significant tendency to delete the codons with CpG or TpA dinucleotides. Turning to the adaptation of the overall codon usage of HCV to that of human, over half part of codons has a similar usage pattern between this virus and human, suggesting that the host cellular environment of the overall codon usage pattern influences the formation of codon usage for HCV. In addition, there is no obvious phenomenon that the codons with relatively low energy tend to be highly selected in the TIR of HCV, suggesting that the synonymous codon usage patterns for the TIR of HCV might be not affected by the secondary structure of nucleotide sequence, however, the formation of synonymous codons usage in the TIR of HCV is influenced by the overall codon usage patterns of human to some degree.

  13. Clustering oxbow lakes in the Upper-Tisza Region on the basis of stable isotope measurements

    NASA Astrophysics Data System (ADS)

    Babka, Beáta; Futó, István; Szabó, Szilárd

    2011-11-01

    SummarySeveral times a year the River Tisza floods areas between dikes, fills the oxbow lakes on the floodplain and changes their water. However the water addition in the oxbow lakes does not only take place through flooding; it is also likely that water can seep under the surface through the gravelled layers of the old river-beds, and furthermore, precipitation also plays a role. Our goal with this study is to acquire a full, comprehensive picture of the water addition of the oxbow lakes in the Upper-Tisza Region. Surface and groundwater samples were taken from the River Tisza, the oxbow lakes and the boreholes around four oxbow lakes, and stabile isotope ratios were measured. We can get information on the origin, the evaporation and the state of the waters, and the depth of the water table with the help of δ18O VSMOW (‰) and δD VSMOW (‰). During the examination the question we addressed was how oxbow lakes can be classified according to their water addition on the basis of their stable isotope ratios. The results from the Tisza and the oxbow lakes, as well as the results from the oxbow lakes on the reclaimed side and the floodplain are also isolated.

  14. Dissociative recombination of H+(H2O)3 and D+(D2O)3 water cluster ions with electrons: Cross sections and branching ratios

    NASA Astrophysics Data System (ADS)

    Öjekull, J.; Andersson, P. U.; Nâgârd, M. B.; Pettersson, J. B. C.; Marković, N.; Derkatch, A. M.; Neau, A.; Al Khalili, A.; Rosén, S.; Larsson, M.; Semaniak, J.; Danared, H.; Källberg, A.; Österdahl, F.; af Ugglas, M.

    2007-11-01

    Dissociative recombination (DR) of the water cluster ions H+(H2O)3 and D+(D2O)3 with electrons has been studied at the heavy-ion storage ring CRYRING (Manne Siegbahn Laboratory, Stockholm University). For the first time, absolute DR cross sections have been measured for H+(H2O)3 in the energy range of 0.001-0.8eV, and relative cross sections have been measured for D+(D2O)3 in the energy range of 0.001-1.0eV. The DR cross sections for H+(H2O)3 are larger than previously observed for H+(H2O)n (n=1,2), which is in agreement with the previously observed trend indicating that the DR rate coefficient increases with size of the water cluster ion. Branching ratios have been determined for the dominating product channels. Dissociative recombination of H+(H2O)3 mainly results in the formation of 3H2O+H (probability of 0.95±0.05) and with a possible minor channel resulting in 2H2O+OH+H2 (0.05±0.05). The dominating channels for DR of D+(D2O)3 are 3D2O+D (0.88±0.03) and 2D2O+OD+D2 (0.09±0.02). The branching ratios are comparable to earlier DR results for H+(H2O)2 and D+(D2O)2, which gave 2X2O+X (X=H,D) with a probability of over 0.9.

  15. {sup 12}C({alpha},{gamma}){sup 16}O E2 cross section: R-matrix fits combined with a microscopic cluster model

    SciTech Connect

    Dufour, M.

    2008-07-15

    The E2 component of the {sup 12}C({alpha},{gamma}){sup 16}O cross section is investigated in two ways: by a microscopic cluster model, and by R-matrix fits. The {alpha}+{sup 12}C microscopic calculation is performed in the framework of the generator coordinate method (GCM) by including all {sup 12}C states (T=0) within the p shell. Using different nucleon-nucleon interactions we find S{sub E2}(300 keV){approx_equal}50 keV {center_dot} b for ground-state transitions. We also study cascade transitions to the 0{sub 2}{sup +} and 2{sub 1}{sup +} excited states of {sup 16}O. Then the S-factor is analyzed in the phenomenological R-matrix theory. We show that the background term plays a crucial role, and cannot be determined without ambiguity. Using the experimental phase shifts and capture cross sections, only an upper limit on the extrapolated S factor can be obtained [S{sub E2}(300 keV)<190 keV {center_dot} b]. To constrain the R-matrix analysis, we use the GCM asymptotic normalization constant (ANC) of the 2{sub 1}{sup +} level, well known to be a cluster state. This procedure strongly reduces the uncertainties on the R-matrix fit, and we end up with a recommended value of S{sub E2}(300 keV)=42{+-}2 keV {center_dot} b. We show that ANC values derived from indirect methods are not consistent with the {sup 12}C({alpha},{gamma}){sup 16}O cascade transitions to the 2{sub 1}{sup +} state, and suggest that a remeasurement of this cross section is desirable.

  16. Molecular epidemiology of Coxiella burnetii in French livestock reveals the existence of three main genotype clusters and suggests species-specific associations as well as regional stability.

    PubMed

    Joulié, Aurelien; Sidi-Boumedine, Karim; Bailly, Xavier; Gasqui, Patrick; Barry, Séverine; Jaffrelo, Lydia; Poncet, Charles; Abrial, David; Yang, Elise; Leblond, Agnès; Rousset, Elodie; Jourdain, Elsa

    2017-03-01

    Q fever is a worldwide zoonosis caused by the bacterium Coxiella burnetii. In domestic ruminants, Q fever main clinical manifestations are abortions. Although the clinical signs may differ between ruminant species, C. burnetii's genetic diversity remains understudied in enzootic areas. Here, we focused on France, where Q fever is enzootic, with the aims to (a) identify potential associations between C. burnetii genotypes and ruminant host species; (b) assess the distribution of C. burnetii genotypes both within French farms and across France's major livestock-farming regions; and (c) suggest a subset of markers for future genotypic studies. We used DNA samples collected between 2006 and 2015 from 301 females (160 cows, 76 ewes, 65 goats) aborted of Q fever within 7 different farming regions. C. burnetii diversity was determined using a multiple-locus variable-number of tandem repeat analysis (MLVA) considering 17 markers. Using a phylogenetic approach, we identified 3 main genotypic clusters divided into 12 sub-clusters. These clusters were significantly associated with ruminant species: almost all the cattle genotypes were found in a "cattle-specific" cluster whereas small ruminants genotypes essentially grouped into the two other clusters. The clusters also proved stable over space and time, some genotypes being more specifically observed in certain farming regions. We also observed some within-farm diversity but this diversity was restricted to a same genotypic cluster. Finally, we identified 6 MLVA markers that maximized the representativeness of the diversity described. Overall, we highlighted that molecular epidemiology is a relevant approach to assess C. burnetii's genetic diversity and to reveal the existence of species-specific associations and regional stability. These results will be valuable in the field to trace genotype circulation among ruminants and from ruminants to humans. Ultimately, the potential links between genotypes and virulence traits need

  17. [Relationships between soil and environment in peak-cluster depression areas of Karst region based on canonical correspondence analysis].

    PubMed

    Yue, Yue-Min; Wang, Ke-Lin; Zhang, Wei; Chen, Hong-Song; Wang, Min

    2008-05-01

    Karst region is a typical ecological fragile zone, with small environmental and anti-interference capability. Many environment factors, such as different land use, elevation and topographic relief, have significant influence on spatial variability of soil properties, resulting in abnormal fragments of landscape and severe rocky desertification. The method of canonical correspondence analysis (CCA) was employed to reveal the relationships between soil and environment in peak-cluster depression areas of karst region, using the samples from field survey in Guzhou. Results show that spatial variability of TN, AN, SOC, AP, AK and C/N are greater than TP, TK, and pH, with the similar trend among TN, AN and SOC. Furthermore, CCA shows that SOC, TN and AN have high correlation with bare rock rate and grade, AK and vegetation type, together with the significant correlation between C/N and soil depth, while the environment has little effect on TK, TP and pH. Environmental factors that affect soil properties are listed as the following order: land use > vegetation type > bare rock rate > aspect > soil depth > elevation. Except TK and pH, soil properties are significantly affected by different land-use types.

  18. Imaging of diffuse H I absorption structure in the SSA22 proto-cluster region at z = 3.1

    NASA Astrophysics Data System (ADS)

    Mawatari, Ken; Inoue, Akio K.; Yamada, Toru; Hayashino, Tomoki; Otsuka, Takuya; Matsuda, Yuichi; Umehata, Hideki; Ouchi, Masami; Mukae, Shiro

    2017-01-01

    Using galaxies as background light sources to map intervening Lyα absorption is a novel approach to study the interplay among galaxies, the circum-galactic medium (CGM), and the intergalactic medium (IGM). Introducing a new measure of z = 3.1 H I Lyα absorption relative to the cosmic mean, ΔNB497, estimated from photometric data of star-forming galaxies at 3.3 ⪉ z ⪉ 3.5, we have made two-dimensional ΔNB497 maps in the z = 3.1 SSA22 proto-cluster region and two control fields (SXDS and GOODS-N fields) with a spatial resolution of ˜5 comoving Mpc. The ΔNB497 measurements in the SSA22 field are systematically larger than those in the control fields, and this H I absorption enhancement extends more than 50 comoving Mpc. The field-averaged (i.e., ˜50 comoving Mpc scale) ΔNB497 and the overdensity of Lyα emitters (LAEs) seem to be correlated, while there is no clear dependency of the ΔNB497 on the local LAE overdensity in a few comoving Mpc scale. These results suggest that diffuse H I gas spreads out in/around the SSA22 proto-cluster. We have also found an enhancement of ΔNB497 at a projected distance <100 physical kpc from the nearest z = 3.1 galaxies at least in the SSA22 field, which is probably due to H I gas associated with the CGM of individual galaxies. The H I absorption enhancement in the CGM-scale tends to be weaker around galaxies with stronger Lyα emission, which suggests that the Lyα escape fraction from galaxies depends on hydrogen neutrality in the CGM.

  19. Exploring the crowded central region of ten Galactic globular clusters using EMCCDs. Variable star searches and new discoveries

    NASA Astrophysics Data System (ADS)

    Figuera Jaimes, R.; Bramich, D. M.; Skottfelt, J.; Kains, N.; Jørgensen, U. G.; Horne, K.; Dominik, M.; Alsubai, K. A.; Bozza, V.; Calchi Novati, S.; Ciceri, S.; D'Ago, G.; Galianni, P.; Gu, S.-H.; Harpsøe, K. B. W.; Haugbølle, T.; Hinse, T. C.; Hundertmark, M.; Juncher, D.; Korhonen, H.; Mancini, L.; Popovas, A.; Rabus, M.; Rahvar, S.; Scarpetta, G.; Schmidt, R. W.; Snodgrass, C.; Southworth, J.; Starkey, D.; Street, R. A.; Surdej, J.; Wang, X.-B.; Wertz, O.

    2016-04-01

    Aims: We aim to obtain time-series photometry of the very crowded central regions of Galactic globular clusters; to obtain better angular resolution thanhas been previously achieved with conventional CCDs on ground-based telescopes; and to complete, or improve, the census of the variable star population in those stellar systems. Methods: Images were taken using the Danish 1.54-m Telescope at the ESO observatory at La Silla in Chile. The telescope was equipped with an electron-multiplying CCD, and the short-exposure-time images obtained (ten images per second) were stacked using the shift-and-add technique to produce the normal-exposure-time images (minutes). Photometry was performed via difference image analysis. Automatic detection of variable stars in the field was attempted. Results: The light curves of 12 541 stars in the cores of ten globular clusters were statistically analysed to automatically extract the variable stars. We obtained light curves for 31 previously known variable stars (3 long-period irregular, 2 semi-regular, 20 RR Lyrae, 1 SX Phoenicis, 3 cataclysmic variables, 1 W Ursae Majoris-type and 1 unclassified) and we discovered 30 new variables (16 long-period irregular, 7 semi-regular, 4 RR Lyrae, 1 SX Phoenicis and 2 unclassified). Fluxes and photometric measurements for these stars are available in electronic form through the Strasbourg astronomical Data Center. Based on data collected by the MiNDSTEp team with the Danish 1.54m telescope at ESO's La Silla observatory in Chile.Full Table 1 is only available at CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/588/A128

  20. Genomic predictions in Angus cattle: comparisons of sample size, response variables, and clustering methods for cross-validation.

    PubMed

    Boddhireddy, P; Kelly, M J; Northcutt, S; Prayaga, K C; Rumph, J; DeNise, S

    2014-02-01

    Advances in genomics, molecular biology, and statistical genetics have created a paradigm shift in the way livestock producers pursue genetic improvement in their herds. The nexus of these technologies has resulted in combining genotypic and phenotypic information to compute genomically enhanced measures of genetic merit of individual animals. However, large numbers of genotyped and phenotyped animals are required to produce robust estimates of the effects of SNP that are summed together to generate direct genomic breeding values (DGV). Data on 11,756 Angus animals genotyped with the Illumina BovineSNP50 Beadchip were used to develop genomic predictions for 17 traits reported by the American Angus Association through Angus Genetics Inc. in their National Cattle Evaluation program. Marker effects were computed using a 5-fold cross-validation approach and a Bayesian model averaging algorithm. The accuracies were examined with EBV and deregressed EBV (DEBV) response variables and with K-means and identical by state (IBS)-based cross-validation methodologies. The cross-validation accuracies obtained using EBV response variables were consistently greater than those obtained using DEBV (average correlations were 0.64 vs. 0.57). The accuracies obtained using K-means cross-validation were consistently smaller than accuracies obtained with the IBS-based cross-validation approach (average correlations were 0.58 vs. 0.64 with EBV used as a response variable). Comparing the results from the current study with the results from a similar study consisting of only 2,253 records indicated that larger training population size resulted in higher accuracies in validation animals and explained on average 18% (69% improvement) additional genetic variance across all traits.

  1. La Crosse Virus in Aedes japonicus japonicus mosquitoes in the Appalachian Region, United States.

    PubMed

    Harris, M Camille; Dotseth, Eric J; Jackson, Bryan T; Zink, Steven D; Marek, Paul E; Kramer, Laura D; Paulson, Sally L; Hawley, Dana M

    2015-04-01

    La Crosse virus (LACV), a leading cause of arboviral encephalitis in children in the United States, is emerging in Appalachia. For local arboviral surveillance, mosquitoes were tested. LACV RNA was detected and isolated from Aedes japonicus mosquitoes. These invasive mosquitoes may significantly affect LACV range expansion and dynamics.

  2. Synthesis of a new potential biodegradable disulfide containing poly(ethylene imine)-poly(ethylene glycol) copolymer cross-linked with click cluster for gene delivery.

    PubMed

    Zhao, Nan; Roesler, Susanne; Kissel, Thomas

    2011-06-15

    Poly(ethylene glycol)-grafted-polyethylenimine (PEG-PEI) are promising non-viral gene delivery systems. Herein, we aimed to synthesize a biodegradable disulfide containing PEGylated PEI to attempt to reduce its cytotoxicity and enhance the gene transfer activity. Using click chemistry, low Mw PEI (br. 2 kDa) and short chain length PEG (tetraethylene glycol, TEG) were cross-linked to a high Mw PEG-PEI copolymer (∼ 22 kDa). The chemical structure of the copolymer was characterized using (1)H NMR and GPC. The degradation behavior was investigated under in vitro conditions in the presence of 1,4-dithiothreitol (DTT). The gel retardation assay, dynamic light scattering and atomic force microscopy showed good DNA condensation ability by forming polyplexes with small particle size and positive zeta potential. In particular, MTT assay indicated that this PEG-PEI polymer is about 22-fold less toxic than PEI 25k and only 2-fold more toxic than PEI 2k in L929 cell line. After coupling of small PEG chains and cross-linking by disulfide bridges, the transfection efficiency is increased approximately 6-fold in comparison to PEI 2k and still reaches approximately 17% of PEI 25k. Hence, this click cluster cross-linked disulfide containing PEG-PEI copolymer could be an attractive cationic polymer for non-viral gene delivery.

  3. A Chandra Study of the Rosette Star-forming Complex. III. The NGC 2237 Cluster and the Region's Star Formation History

    NASA Astrophysics Data System (ADS)

    Wang, Junfeng; Feigelson, Eric D.; Townsley, Leisa K.; Broos, Patrick S.; Román-Zúñiga, Carlos G.; Lada, Elizabeth; Garmire, Gordon

    2010-06-01

    We present high spatial resolution Chandra X-ray images of the NGC 2237 young stellar cluster on the periphery of the Rosette Nebula. We detect 168 X-ray sources, 80% of which have stellar counterparts in USNO, Two Micron All Sky Survey, and deep FLAMINGOS images. These constitute the first census of the cluster members with 0.2 <~ M <~ 2 M sun. Star locations in near-infrared color-magnitude diagrams indicate a cluster age around 2 Myr with a visual extinction of 1 <~ AV <~ 3 at 1.4 kpc, the distance of the Rosette Nebula's main cluster NGC 2244. We derive the K-band luminosity function and the X-ray luminosity function of the cluster, which indicate a population ~400-600 stars. The X-ray-selected sample shows a K-excess disk frequency of 13%. The young Class II counterparts are aligned in an arc ~3 pc long suggestive of a triggered formation process induced by the O stars in NGC 2244. The diskless Class III sources are more dispersed. Several X-ray emitting stars are located inside the molecular cloud and around gaseous pillars projecting from the cloud. These stars, together with a previously unreported optical outflow originating inside the cloud, indicate that star formation is continuing at a low level and the cluster is still growing. This X-ray view of young stars on the western side of the Rosette Nebula complements our earlier studies of the central cluster NGC 2244 and the embedded clusters on the eastern side of the Nebula. The large-scale distribution of the clusters and molecular material is consistent with a scenario in which the rich central NGC 2244 cluster formed first, and its expanding H II region triggered the formation of the now-unobscured satellite clusters Rosette Molecular Cloud (RMC) XA and NGC 2237. A large swept-up shell material around the H II region is now in a second phase of collect-and-collapse fragmentation, leading to the recent formation of subclusters. Other clusters deeper in the molecular cloud appear unaffected by the

  4. A CHANDRA STUDY OF THE ROSETTE STAR-FORMING COMPLEX. III. THE NGC 2237 CLUSTER AND THE REGION'S STAR FORMATION HISTORY

    SciTech Connect

    Wang Junfeng; Feigelson, Eric D.; Townsley, Leisa K.; Broos, Patrick S.; Garmire, Gordon; Roman-Zuniga, Carlos G.; Lada, Elizabeth

    2010-06-10

    We present high spatial resolution Chandra X-ray images of the NGC 2237 young stellar cluster on the periphery of the Rosette Nebula. We detect 168 X-ray sources, 80% of which have stellar counterparts in USNO, Two Micron All Sky Survey, and deep FLAMINGOS images. These constitute the first census of the cluster members with 0.2 {approx}< M {approx}< 2 M {sub sun}. Star locations in near-infrared color-magnitude diagrams indicate a cluster age around 2 Myr with a visual extinction of 1 {approx}< A{sub V} {approx}< 3 at 1.4 kpc, the distance of the Rosette Nebula's main cluster NGC 2244. We derive the K-band luminosity function and the X-ray luminosity function of the cluster, which indicate a population {approx}400-600 stars. The X-ray-selected sample shows a K-excess disk frequency of 13%. The young Class II counterparts are aligned in an arc {approx}3 pc long suggestive of a triggered formation process induced by the O stars in NGC 2244. The diskless Class III sources are more dispersed. Several X-ray emitting stars are located inside the molecular cloud and around gaseous pillars projecting from the cloud. These stars, together with a previously unreported optical outflow originating inside the cloud, indicate that star formation is continuing at a low level and the cluster is still growing. This X-ray view of young stars on the western side of the Rosette Nebula complements our earlier studies of the central cluster NGC 2244 and the embedded clusters on the eastern side of the Nebula. The large-scale distribution of the clusters and molecular material is consistent with a scenario in which the rich central NGC 2244 cluster formed first, and its expanding H II region triggered the formation of the now-unobscured satellite clusters Rosette Molecular Cloud (RMC) XA and NGC 2237. A large swept-up shell material around the H II region is now in a second phase of collect-and-collapse fragmentation, leading to the recent formation of subclusters. Other clusters deeper

  5. Hubble Space Telescope Discovery of a Probable Caustic-Crossing Event in the MACS1149 Galaxy Cluster Field

    NASA Astrophysics Data System (ADS)

    Kelly, Patrick L.; Rodney, Steven; Diego, Jose Maria; Zitrin, Adi; Broadhurst, Tom; Selsing, Jonatan; Balestra, Italo; Benito, Alberto Molino; Bradac, Marusa; Bradley, Larry; Brammer, Gabriel; Cenko, Brad; Christensen, Lise; Coe, Dan; Filippenko, Alexei V.; Foley, Ryan; Frye, Brenda; Graham, Melissa; Graur, Or; Grillo, Claudio; Hjorth, Jens; Howell, Andy; Jauzac, Mathilde; Jha, Saurabh; Kaiser, Nick; Kawamata, Ryota; Kneib, Jean-Paul; Lotz, Jennifer; Matheson, Thomas; McCully, Curtis; Merten, Julian; Nonino, Mario; Oguri, Masamune; Richard, Johan; Riess, Adam; Rosati, Piero; Schmidt, Kasper Borello; Sharon, Keren; Smith, Nathan; Strolger, Lou; Treu, Tommaso; Wang, Xin; Weiner, Ben; Williams, Liliya; Zheng, Weikang

    2016-05-01

    While monitoring the MACS1149 (z = 0.54) galaxy cluster as part of the RefsdalRedux program (PID 14199; PI Kelly) with the Hubble Space Telescope (HST) WFC3 IR camera, we have detected a rising transient that appears to be coincident ( Target-of-opportunity optical follow-up imaging in several ACS and WFC3 bands with the FrontierSN program (PID 14208; PI Rodney) has revealed that its rest-frame ultraviolet through optical spectrum may be reasonably well fit with that of a B star at z=1.49 exhibiting a strong Balmer break.

  6. Dynamics and characteristics of electric-field structures in the auroral return current region observed by Cluster

    NASA Astrophysics Data System (ADS)

    Marklund, G. T.; Karlsson, T.; Figueiredo, S.; Johansson, T.; Lindqvist, P.-A.; André, M.; Buchert, S.; Kistler, L. M.

    2006-02-01

    The temporal evolution and other characteristics of intense quasi-static electric fields in the return current region are discussed using Cluster observations. A narrow-scale, divergent electric field, the high-altitude signature of a positive U-shaped potential structure, was observed at the poleward edge of the central plasma sheet, close to magnetic midnight at a geocentric distance of about 4.2 Earth radii. Its acceleration potential increased from less than 1 to 3 kV on a 100 s timescale, similar to the formation time for ionospheric plasma density holes, and consistent with previous results for this kind of structure. In the adjacent upward current region, an energy decrease in inverted-V ions was observed some minutes prior to this. The inverted-V potential decrease was roughly equal to the subsequent perpendicular potential increase in the return current region, suggesting that a potential redistribution took place between the two adjacent current branches. Other characteristics of this and three other return current structures are summarized, to illustrate both common and different features of these. The structures are characterized by (all values have been mapped to the ionospheric level) peak electric-field magnitudes of ap1 V m-1, bipolar or unipolar profiles, occurrence at plasma boundaries associated with plasma density gradients, perpendicular scale sizes of ap10 km, downward field-aligned currents of ap10 μA m-2, and upward electron beams with characteristic energies of a few hundred to a few thousand eV. The bipolar and unipolar electric-field profiles are proposed to reflect whether plasma populations, dense enough to support upward field-aligned currents (by which the return current can close) exist on both sides, or on one side only of the boundary.

  7. Appalachia in an International Context: Cross-National Comparisons of Developing Regions.

    ERIC Educational Resources Information Center

    Obermiller, Phillip J., Ed.; Philliber, William W., Ed.

    This book contains 11 essays that compare economic and social conditions in Appalachia to those in rural regions of other countries. These rural, frequently mountainous, regions suffer similar economic problems due to their peripheral position in the national economies of their countries. Among the topics of particular educational interest are the…

  8. Clustering of Subgingival Microbiota Reveals Microbial Disease Ecotypes Associated with Clinical Stages of Periodontitis in a Cross-Sectional Study

    PubMed Central

    Boutin, Sébastien; Hagenfeld, Daniel; Zimmermann, Heiko; El Sayed, Nihad; Höpker, Tanja; Greiser, Halina K.; Becher, Heiko; Kim, Ti-Sun; Dalpke, Alexander H.

    2017-01-01

    Periodontitis is characterized by chronic inflammation associated with alteration of the oral microbiota. In contrast to previous microbiome studies focusing a priori on comparison between extreme phenotypes, our study analyzed a random sample of 85 people. The aim of this study was to link microbial differences to disease’s prevalence and severity. Using next generation sequencing of 16S rRNA amplicons and cluster analysis, we observed that the population can be divided into two major ecotypes: One mainly contained periodontal healthy/mild periodontitis individuals whereas the second ecotype showed a heterogeneous microbial distribution and clustered into three distinct sub-ecotypes. Those sub-ecotypes differed with respect to the frequency of diseased patients and displayed a gradual change in distinct subgingival microbiota that goes along with clinical disease symptoms. In ecotype 2, the subgroup with no clinical signs of disease was linked to an increase of F. nucleatum vincentii but also several other species, while only in “end-stage” dysbiosis classical red complex bacteria gained overweight. Therefore, the microbial disease ecotypes observed in our population can lead to an establishment of an early microbial risk profile for clinically healthy patients. PMID:28298910

  9. Multiphoton transition moments and absorption cross sections in coupled cluster response theory employing variational transition moment functionals

    NASA Astrophysics Data System (ADS)

    Hättig, Christof; Christiansen, Ove; Jørgensen, Poul

    1998-05-01

    Based on an analysis of the first residues of coupled cluster response functions we devise variational functionals from which the transition moments for n-photon excitations can be calculated as nth derivatives. Combining these functionals with variational perturbation theory, we obtain a new approach for the derivation of multiphoton transition moments which allows us to utilize the full strengths of variational perturbation theory without the roundabout way via residues of response functions. Coupled cluster multiphoton transition moments derived by this approach are formally equivalent to the one identified from the first residues of the ground state response functions. The introduction of the variational functionals makes the mathematical structure of the transition moments more transparent and provides an interpretation of intermediates in terms of responses of excited state vectors and Lagrangian multipliers. 2n+1 and 2n+2 rules are formulated for the transition moments and build the basis for a straightforward derivation of a computational efficient formulation. The strength of the new approach is demonstrated by the derivation of three- and four-photon transition moments.

  10. Clustering of Subgingival Microbiota Reveals Microbial Disease Ecotypes Associated with Clinical Stages of Periodontitis in a Cross-Sectional Study.

    PubMed

    Boutin, Sébastien; Hagenfeld, Daniel; Zimmermann, Heiko; El Sayed, Nihad; Höpker, Tanja; Greiser, Halina K; Becher, Heiko; Kim, Ti-Sun; Dalpke, Alexander H

    2017-01-01

    Periodontitis is characterized by chronic inflammation associated with alteration of the oral microbiota. In contrast to previous microbiome studies focusing a priori on comparison between extreme phenotypes, our study analyzed a random sample of 85 people. The aim of this study was to link microbial differences to disease's prevalence and severity. Using next generation sequencing of 16S rRNA amplicons and cluster analysis, we observed that the population can be divided into two major ecotypes: One mainly contained periodontal healthy/mild periodontitis individuals whereas the second ecotype showed a heterogeneous microbial distribution and clustered into three distinct sub-ecotypes. Those sub-ecotypes differed with respect to the frequency of diseased patients and displayed a gradual change in distinct subgingival microbiota that goes along with clinical disease symptoms. In ecotype 2, the subgroup with no clinical signs of disease was linked to an increase of F. nucleatum vincentii but also several other species, while only in "end-stage" dysbiosis classical red complex bacteria gained overweight. Therefore, the microbial disease ecotypes observed in our population can lead to an establishment of an early microbial risk profile for clinically healthy patients.

  11. RoCaSCA: A contour tracing grid-based algorithm to identify similarity regions and clusters in spatial geographical data

    NASA Astrophysics Data System (ADS)

    Hazenberg, P.; Torfs, P. J. J. F.; Leijnse, H.; Uijlenhoet, R.

    2012-04-01

    Over the last decades the amount of spatial geographic data obtained from satellite and radar remote sensing, geographical and other types of spatial information has increased tremendously, making it impossible for a user to examine all in detail. Therefore, a considerable amount of research has focused on smart and efficient solutions to segment a spatial image into its dominant regions, extracting most essential information. The current research presents a new spatial image cluster identification method. The delineation of clusters is performed in two separate steps. First, we identify a regions outer contour using the properties of a rotating carpenter square. Secondly, we define all inner pixels belonging to a cluster based on the same principle, excluding inner contour regions if necessary. As such, a cluster identification method will be presented which has considerable similarity to some of the tracing type and connected component image segmentation algorithms developed in the literature during the last decade. However, since the characteristic shape of a carpenter square can easily be extended, the algorithm presented here does not strictly label neighboring pixels to the same component only. On the contrary, our algorithm is able to connect non-neighboring pixels for varying pixel distances as well. In addition, since our algorithm takes a continuous grid as input, it is possible to define transition pixels, that connect pixels that belong to a given cluster. Therefore, this newly developed algorithm presents a link between the traditional image segmentation methods implemented on binary grids and the partitional density and grid-based cluster identification methods that use continuous datasets. We will demonstrate the impact of this new cluster identification method for a number of typical geophysical cases ranging from global drought identification to weather radar based precipitation cell delineation.

  12. Evaluation of Tungsten Neutron Cross Sections in the Resolved Resonance Regions

    SciTech Connect

    Pigni, Marco T; Leal, Luiz C; Dunn, Michael E; Guber, Klaus H; Emiliani, F.; Kopecky, S.; Lampoudis, C.; Schillebeeckx, P.; Siegler, P.

    2014-01-01

    We generated a preliminary set of resonance parameters for 182-184,186W in the neutron energy range of thermal up to several keV. The evaluation methodology uses the Reich-Moore approximation to t, with the R-matrix code SAMMY, the high-resolution measurements performed in 2010 and 2012 at the GEel LINear Accelerator (GELINA) facility. Particularly for 183W, the transmission data and the capture cross sections calculated with the set of resonance parameters are compared with the experimental values, and some of the average properties of the resonance parameters are discussed. In the analyzed energy range, this work almost doubles the existing resolved resonance evaluations in the ENDF/B-VII.1 library. The analysis of the performance of the calculated cross sections based on criticality benchmarks is still in progress and it is only briefly discussed.

  13. Absorption cross section determination of biogenic C5-aldehydes in the actinic region

    NASA Astrophysics Data System (ADS)

    Lanza, Beatriz; Jiménez, Elena; Ballesteros, Bernabé; Albaladejo, José

    2008-03-01

    UV absorption cross sections ( σλ) for 3-methylbutanal, trans-2-methyl-2-butenal, and 3-methyl-2-butenal have been determined between 255 and 390 nm and as a function of temperature (273-305 K). A D 2 lamp and a 0.5 m spectrograph coupled to a charged-couple device were employed in these measurements. σλ values were found to be independent of temperature in the range studied. The cross section data reported in this Letter were used to provide estimates of the photolysis rate coefficients ( Ji) for these compounds as a function of altitude in the troposphere. Photolysis and OH reaction both appear to be important in determining the atmospheric fate of these compounds.

  14. Analyses of MAGSAT tracks crossing the study region in the Indian Ocean

    NASA Technical Reports Server (NTRS)

    Sailor, R. V.; Lazarewicz, A. R. (Principal Investigator)

    1981-01-01

    Progress in software development and in preliminary analysis of MAGSAT tracks crossing the Indian Ocean is reported. Tracks crossing the Java Trench, Broken Ridge, the Southeast Indian Ridge, and the Ninetyeast Ridge show that magnetic anomalies correlate with some of these features. Preliminary study of anomaly profiles indicates that tracks of anomaly data (the observations minus a core field model) have a power spectrum decreasing as the inverse square of the spatial frequency. An apparent noise floor of about one to two gammas rms is reached at wavelengths of about 360 km, corresponding to approximately 10 samples of the decimated Investigator tape data at a sampling rate of approximately 4.9 sec/sample.

  15. LOW-FIDELITY CROSS SECTION COVARIANCES FOR 219 FISSION PRODUCTS IN THE FIRST NEUTRON REGION.

    SciTech Connect

    PIGNI,M.T.; HERMAN, M.; OBLOZINSKY, P.; ROCHMAN, D.

    2007-04-27

    An extensive set of covariances for neutron cross sections in the energy range 5 keV-20 MeV has been developed to provide initial, low-fidelity but consistent uncertainty data for nuclear criticality safety applications. The methodology for the determination of such covariances combines the nuclear reaction model code EMPIRE, which calculates sensitivity to nuclear reaction model parameters, and the Bayesian code KALMAN to propagate uncertainty of the model parameters to cross sections. Taking into account the large scale of the project (219 fission products), only partial reference to experimental data has been made. Therefore, the covariances are, to a large extent, derived from the perturbation of several critical model parameters selected through the sensitivity analysis. These parameters define optical potential, level densities and pre-equilibrium emission. This work represents the first attempt ever to generate nuclear data covariances on such a scale.

  16. Minimum package for cross-border TB control and care in the WHO European region: a Wolfheze consensus statement

    PubMed Central

    Dara, Masoud; de Colombani, Pierpaolo; Petrova-Benedict, Roumyana; Centis, Rosella; Zellweger, Jean-Pierre; Sandgren, Andreas; Heldal, Einar; Sotgiu, Giovanni; Jansen, Niesje; Bahtijarevic, Rankica; Migliori, Giovanni Battista

    2012-01-01

    The World Health Organization (WHO) European region estimates that more than 400,000 tuberculosis (TB) cases occur in Europe, a large proportion of them among migrants. A coordinated public health mechanism to guarantee TB prevention, diagnosis, treatment and care across borders is not in place. A consensus paper describing the minimum package of cross-border TB control and care was prepared by a task force following a literature review, and with input from the national TB control programme managers of the WHO European region and the Wolfheze 2011 conference. A literature review focused on the subject of TB in migrants was carried out, selecting documents published during the 11-yr period 2001–2011. Several issues were identified in cross-border TB control and care, varying from the limited access to early TB diagnosis, to the lack of continuity of care and information during migration, and the availability of, and access to, health services in the new country. The recommended minimum package addresses the current shortcomings and intends to improve the situation by covering several areas: political commitment (including the implementation of a legal framework for TB cross-border collaboration), financial mechanisms and adequate health service delivery (prevention, infection control, contact management, diagnosis and treatment, and psychosocial support). PMID:22653772

  17. Level Densities in the actinide region and indirect n,y cross section measurements using the surrogate method

    NASA Astrophysics Data System (ADS)

    Wilson, J. N.; Gunsing, F.; Bernstein, L.; Bürger, A.; Görgen, A.; Thompson, I. J.; Guttormssen, M.; Larsen, A.-C.; Mansouri, P.; Renstrøm, T.; Rose, S. J.; Siem, S.; Wiedeking, M.; Wiborg, T.

    2012-02-01

    Results from a program of measurements of level densities and gamma ray strength functions in the actinide region are presented. Experiments at the Oslo cyclotron involving the Cactus/Siri detectors and 232Th(d,x) and 232Th(3He,x) reactions were carried out to help answer the question of which level density model is the most appropriate for actinide nuclei, since it will have an impact on cross section calculations important for reactor physics simulations. A new technique for extracting level densities and gamma ray strength functions from particle-gamma coincidence data is proposed and results from the development of this technique are presented. In addition, simultaneous measurements of compound nuclear gamma decay probabilities have been performed for the key thorium cycle nuclei 233Th, 231Th and 232Pa up to around 1MeV above the neutron binding energy and have enabled extraction of indirect neutron induced capture cross sections for the 232Th, 231Pa and 230Th nuclei using the surrogate reaction method. Since the neutron capture cross section for 232Th is already well known from direct measurements a comparison provides a stringent test of the applicability of the surrogate technique in the actinide region.

  18. [Sanitary and relief activity of the Polish Red Cross in the repatriation and displacement action in the Western Pomeranian region].

    PubMed

    Kedzia, A

    2001-01-01

    The final period of World War II and the first months of peace were the time of massive migration of Polish and German population. The first stage of the Poles' repatriation from the territories taken over by the USSR to the liberated parts of Poland underwent in an organizational chaos, which resulted from poor coordination between the institutions responsible for this operation. In principle, the National Repatriation Office was in charge of the repatriation action. However, where the NRO had no branches or wanted a joint action, the Polish Red Cross took a vital part in sanitary and relief activities. They were particularly crucial in the western and northern regions of Poland, which faced three massive migration currents: the influx of Polish repatriates from the USSR, the return of concentration camp prisoners, POWs and slave workers from Germany and the displacement of the German population. Colonel Jan Ciałowicz gave a brief résumé of the role the Polish Red Cross played in the repatriation and displacement action: "... At the time when the foundations of the State of Poland were created in the Western Pomeranian Region, the Polish Red Cross was dressing, feeding and treating those who needed it most desperately, taking special care of the repatriates and children."

  19. The Substellar Mass Function in the Central Region of the Open Cluster Praesepe from Deep LBT Observations

    NASA Astrophysics Data System (ADS)

    Wang, W.; Boudreault, S.; Goldman, B.; Henning, Th.; Caballero, J. A.; Bailer-Jones, C. A. L.

    2011-12-01

    Studies of the mass function (MF) of open clusters of different ages allow us to probe the efficiency with which brown dwarfs (BDs) are evaporated from clusters to populate the field. Surveys in old clusters (age gtrsim 100 Myr) do not suffer so severely from several problems encountered in young clusters, such as intra-cluster extinction and large uncertainties in BD models. Here we present the results of a deep photometric survey to study the MF of the old open cluster Praesepe (age 590+150-120 Myr and distance 190+6.0-5.8 pc), down to a 5σ detection limit at i˜25.6 mag (˜40 MJup). We identify 62 cluster member candidates, of which 40 are substellar, from comparison with predictions from a dusty atmosphere model. The MF rises from the substellar boundary until ˜60 MJup and then declines. This is quite different from the form inferred for other open clusters older than 50 Myr, but seems to be similar to those found in very young open cluster, whose MFs peak at ˜10 MJup. Either Praesepe really does have a different MF from other clusters or they had similar initial MFs but have differed in their dynamical evolution. We further have identified six foreground T dwarf candidates towards Praesepe, which require follow-up spectroscopy to confirm their nature.

  20. Scattering of electrons on metal clusters and fullerenes

    NASA Astrophysics Data System (ADS)

    Gerchikov, Leonid G.; Solov'yov, Andrey V.; Connerade, Jean-Patrick; Greiner, Walter

    1997-09-01

    It is shown that the main contribution to the elastic cross section of fast electrons on metal clusters and fullerenes results from scattering on the frozen cluster potential, which is determined by the electron density distribution of the ground state of the target cluster. The specific shape of the electron distribution in fullerenes and metal clusters manifests itself in the diffraction behaviour of the elastic differential cross section. The analysis of the total elastic cross section dependence upon projectile velocity, the number of atoms in the cluster and its size is provided. The cross section of elastic scattering on a cluster surpasses the sum of the individual scattering cross sections on the equivalent number of isolated atoms. This occurs because of the coherent interaction of the projectile electron with electrons delocalized in the cluster volume. We have demonstrated that collective electron excitations sensitive to the many-electron correlations dominate inelastic scattering. The surface plasmon resonances can be observed in the differential cross section for inelastic scattering. We found a condition for the quadrupole and higher multipole plasmon excitations to contribute relatively little to the electron energy loss spectrum. The results obtained have been compared with experimental data for the electron - fullerene 0953-4075/30/18/013/img7 collision. Reasonable agreement between theoretical and experimental results is reported. We have also demonstrated that plasmon excitations provide the main contribution to the total inelastic cross section over a wide energy range. We have calculated the dependence of the total inelastic cross section on collision energy and compared the result obtained with the experimental data available, giving an interpretation for the plateau region in the cross section as caused by plasmon excitations rather than the cluster fragmentation process. We have shown that the single-particle jellium approximation fails to

  1. Active index model: a unique approach for regional quantitative morphometry in longitudinal and cross-sectional studies

    NASA Astrophysics Data System (ADS)

    Saha, P. K.; Zhang, H.; Sonka, M.; Christensen, G. E.; Rajapakse, C. S.

    2007-03-01

    Recent advancements in digital medical imaging have opened avenues for quantitative analyses of different volumetric and morphometric indices in response to a disease or a treatment. However, a major challenge in performing such an analysis is the lack of a technology of building a mean anatomic space (MAS) that allows mapping data of a given subject onto MAS. This approach leads to a tool for point-by-point regional analysis and comparison of quantitative indices for data coming from a longitudinal or transverse study. Toward this goal, we develop a new computation technique, called Active Index Model (AIM), which is a unique tool to solve the stated problem. AIM consists of three building blocks - (1) development of MAS for a particular anatomic site, (2) mapping a specific data onto MAS, (3) regional statistical analysis of data from different populations assessing regional response to a disease or treatment progression. The AIM presented here is built at the training phase from two known populations (e.g., normal and diseased) which will be immediately ready for diagnostic purpose in a subject whose clinical status is unknown. AIM will be useful for both cross sectional and longitudinal studies and for early diagnostic. This technique will be a vital tool for understanding regional response of a disease or treatment at various stages of its progression. This method has been applied for analyzing regional trabecular bone structural distribution in rabbit femur via micro-CT imaging and to localize the affected myocardial regions from cardiac MR data.

  2. αβ T cell receptor germline CDR regions moderate contact with MHC ligands and regulate peptide cross-reactivity

    PubMed Central

    Attaf, Meriem; Holland, Stephan J.; Bartok, Istvan; Dyson, Julian

    2016-01-01

    αβ T cells respond to peptide epitopes presented by major histocompatibility complex (MHC) molecules. The role of T cell receptor (TCR) germline complementarity determining regions (CDR1 and 2) in MHC restriction is not well understood. Here, we examine T cell development, MHC restriction and antigen recognition where germline CDR loop structure has been modified by multiple glycine/alanine substitutions. Surprisingly, loss of germline structure increases TCR engagement with MHC ligands leading to excessive loss of immature thymocytes. MHC restriction is, however, strictly maintained. The peripheral T cell repertoire is affected similarly, exhibiting elevated cross-reactivity to foreign peptides. Our findings are consistent with germline TCR structure optimising T cell cross-reactivity and immunity by moderating engagement with MHC ligands. This strategy may operate alongside co-receptor imposed MHC restriction, freeing germline TCR structure to adopt this novel role in the TCR-MHC interface. PMID:27775030

  3. αβ T cell receptor germline CDR regions moderate contact with MHC ligands and regulate peptide cross-reactivity.

    PubMed

    Attaf, Meriem; Holland, Stephan J; Bartok, Istvan; Dyson, Julian

    2016-10-24

    αβ T cells respond to peptide epitopes presented by major histocompatibility complex (MHC) molecules. The role of T cell receptor (TCR) germline complementarity determining regions (CDR1 and 2) in MHC restriction is not well understood. Here, we examine T cell development, MHC restriction and antigen recognition where germline CDR loop structure has been modified by multiple glycine/alanine substitutions. Surprisingly, loss of germline structure increases TCR engagement with MHC ligands leading to excessive loss of immature thymocytes. MHC restriction is, however, strictly maintained. The peripheral T cell repertoire is affected similarly, exhibiting elevated cross-reactivity to foreign peptides. Our findings are consistent with germline TCR structure optimising T cell cross-reactivity and immunity by moderating engagement with MHC ligands. This strategy may operate alongside co-receptor imposed MHC restriction, freeing germline TCR structure to adopt this novel role in the TCR-MHC interface.

  4. Strain measurement in the wavy-ply region of an externally pressurized cross-ply composite ring

    SciTech Connect

    Gascoigne, H.E.; Abdallah, M.G.

    1996-07-01

    Ply-level strains are determined in the cross-section of an externally pressurized cross-ply (3:1 circumferential to axial fiber ratio) graphite-epoxy ring containing an isolated circumferential wavy region. A special test fixture was used which permitted measuring orthogonal displacement components in the wavy area using moire interferometry as the pressure was increased. Strain components were determined at selected locations in the wavy area up to approximately90% of failure pressure. The study shows: (1) large interlaminar shear strains, which are non-existent in the perfect ring, are present near the wave inflection points; (2) the wavy plies generate increased interlaminar normal compressive strains in both circumferential and axial plies along a radial line coinciding with maximum wave amplitude; and (3) nonlinear strain response begins at approximately 60% of failure pressure.

  5. Co-occurrence and clustering of health conditions at age 11: cross-sectional findings from the Millennium Cohort Study

    PubMed Central

    Hesketh, Kathryn R; Fagg, James; Muniz-Terrera, Graciela; Law, Catherine; Hope, Steven

    2016-01-01

    Objectives To identify patterns of co-occurrence and clustering of 6 common adverse health conditions in 11-year-old children and explore differences by sociodemographic factors. Design Nationally representative prospective cohort study. Setting Children born in the UK between 2000 and 2002. Participants 11 399 11-year-old singleton children for whom data on all 6 health conditions and sociodemographic information were available (complete cases). Main outcome measures Prevalence, co-occurrence and clustering of 6 common health conditions: wheeze; eczema; long-standing illness (excluding wheeze and eczema); injury; socioemotional difficulties (measured using Strengths and Difficulties Questionnaire) and unfavourable weight (thin/overweight/obese vs normal). Results 42.4% of children had 2 or more adverse health conditions (co-occurrence). Co-occurrence was more common in boys and children from lower income households. Latent class analysis identified 6 classes: ‘normative’ (57.4%): ‘atopic burdened’ (14.0%); ‘socioemotional burdened’ (11.0%); ‘unfavourable weight/injury’ (7.7%); ‘eczema/injury’ (6.0%) and ‘eczema/unfavourable weight’ (3.9%). As with co-occurrence, class membership differed by sociodemographic factors: boys, children of mothers with lower educational attainment and children from lower income households were more likely to be in the ‘socioemotional burdened’ class. Children of mothers with higher educational attainment were more likely to be in the ‘normative’ and ‘eczema/unfavourable weight’ classes. Conclusions Co-occurrence of adverse health conditions at age 11 is common and is associated with adverse socioeconomic circumstances. Holistic, child focused care, particularly in boys and those in lower income groups, may help to prevent and reduce co-occurrence in later childhood and adolescence. PMID:27881529

  6. Hubble Space Telescope photometry of the central regions of Virgo Cluster elliptical galaxies. 1: Observations, discussion, and conclusions

    NASA Technical Reports Server (NTRS)

    Jaffe, Walter; Ford, Holland C.; O'Connell, Robert W.; Bosch, Frank C. Van Den; Ferrarese, Laura

    1994-01-01

    Using the Hubble Space Telescope we have observed at 10 pc resolution the nuclei of a luminosity-limited sample of 14 E and E/SO galaxies in the Virgo Cluster with magnitudes B(sub T) = 9.4 to 13.4. In this paper we present the images, and discuss the results of the detailed analysis of the surface photometry given in two companion papers. We find that the nuclear and near-nuclear morphologies confirm and strengthen the previously recognized dichotomy of 'E' galaxies into 'true' and 'disky' subtypes. The latter, usually classified E4 or later, often show a bright nuclear disk of radius approximately 100 pc. Essentially all early-type galaxies with -18 greater than M(sub B) greater than -20 are disky. Most true E galaxies are classified E4 or earlier. Most galaxies of both types show dust in the nuclear regions, the most remarkable example being a compact dust disk in NGC 4261. Other than dust, no anomalies were detected in the centers of the three galaxies in our sample which show clear kinematic evidence for a decoupled component.

  7. On the onset of secondary stellar generations in giant star-forming regions and massive star clusters

    SciTech Connect

    Palouš, J.; Wünsch, R.; Tenorio-Tagle, G.

    2014-09-10

    Here we consider the strong evolution experienced by the matter reinserted by massive stars, both in giant star-forming regions driven by a constant star formation rate and in massive and coeval superstar clusters. In both cases we take into consideration the changes induced by stellar evolution on the number of massive stars, the number of ionizing photons, and the integrated mechanical luminosity of the star-forming regions. The latter is at all times compared with the critical luminosity that defines, for a given size, the lower mechanical luminosity limit above which the matter reinserted via strong winds and supernova explosions suffers frequent and recurrent thermal instabilities that reduce its temperature and pressure and inhibit its exit as part of a global wind. Instead, the unstable reinserted matter is compressed by the pervasive hot gas, and photoionization maintains its temperature at T ∼ 10{sup 4} K. As the evolution proceeds, more unstable matter accumulates and the unstable clumps grow in size. Here we evaluate the possible self-shielding of thermally unstable clumps against the UV radiation field. Self-shielding allows for a further compression of the reinserted matter, which rapidly develops a high-density neutral core able to absorb in its outer skin the incoming UV radiation. Under such conditions the cold (T ∼ 10 K) neutral cores soon surpass the Jeans limit and become gravitationally unstable, creating a new stellar generation with the matter reinserted by former massive stars. We present the results of several calculations of this positive star formation feedback scenario promoted by strong radiative cooling and mass loading.

  8. On the Onset of Secondary Stellar Generations in Giant Star-forming Regions and Massive Star Clusters

    NASA Astrophysics Data System (ADS)

    Palouš, J.; Wünsch, R.; Tenorio-Tagle, G.

    2014-09-01

    Here we consider the strong evolution experienced by the matter reinserted by massive stars, both in giant star-forming regions driven by a constant star formation rate and in massive and coeval superstar clusters. In both cases we take into consideration the changes induced by stellar evolution on the number of massive stars, the number of ionizing photons, and the integrated mechanical luminosity of the star-forming regions. The latter is at all times compared with the critical luminosity that defines, for a given size, the lower mechanical luminosity limit above which the matter reinserted via strong winds and supernova explosions suffers frequent and recurrent thermal instabilities that reduce its temperature and pressure and inhibit its exit as part of a global wind. Instead, the unstable reinserted matter is compressed by the pervasive hot gas, and photoionization maintains its temperature at T ~ 104 K. As the evolution proceeds, more unstable matter accumulates and the unstable clumps grow in size. Here we evaluate the possible self-shielding of thermally unstable clumps against the UV radiation field. Self-shielding allows for a further compression of the reinserted matter, which rapidly develops a high-density neutral core able to absorb in its outer skin the incoming UV radiation. Under such conditions the cold (T ~ 10 K) neutral cores soon surpass the Jeans limit and become gravitationally unstable, creating a new stellar generation with the matter reinserted by former massive stars. We present the results of several calculations of this positive star formation feedback scenario promoted by strong radiative cooling and mass loading.

  9. Separation of Cloud/No-Cloud Regions in Satellite Imagery Using a Variation of Hierarchical Clustering Analysis

    DTIC Science & Technology

    1991-12-01

    algorithms to use. Once the visible and infrared values for the cluster area have been placed into the array Parray , it is not necessary to have the...realtype; ZVis,ZIR,ZX,ZY realtype; Done .Boolean; Parray array’O. .149,0. 149,0.11 of byte; Cluster_-One_-IR,Cluster_-TwoIR :realtype; Cluster_-One_-Vis...arg); for m :=0 to 149 do (*Set all values in Parray to zero for n :=0 to 149 do begin Parrayfm,n1,0l 0; Parray [m,n,1] 0; end: (for n) for j :y s to

  10. Absolute absorption cross sections of ozone at 300 K, 228 K and 195 K in the wavelength region 185-240 nm

    NASA Technical Reports Server (NTRS)

    Yoshino, K.; Parkinson, W. H.; Freeman, D. E.

    1992-01-01

    An account is given of progress of work on absorption cross section measurements of ozone at 300 K, 228 K and 195 K in the wavelength region 185-240 nm. In this wavelength region, the penetration of solar radiation into the Earth's atmosphere is controlled by O2 and O3. The transmitted radiation is available to dissociate trace species such as halocarbons and nitrous oxide. We have recently measured absolute absorption cross sections of O3 in the wavelength region 240-350 nm (Freeman et al., 1985; Yoshino et al., 1988). We apply these proven techniques to the determination of the absorption cross section of O3 at 300 K, 228 K and 195 K throughout the wavelength region 185-240 nm. A paper titled 'Absolute Absorption Cross Section Measurements of Ozone in the Wavelength Region 185-254 nm and the Temperature Dependence' has been submitted for publication in the Journal of Geophysical Research.

  11. Data Clustering

    NASA Astrophysics Data System (ADS)

    Wagstaff, Kiri L.

    2012-03-01

    On obtaining a new data set, the researcher is immediately faced with the challenge of obtaining a high-level understanding from the observations. What does a typical item look like? What are the dominant trends? How many distinct groups are included in the data set, and how is each one characterized? Which observable values are common, and which rarely occur? Which items stand out as anomalies or outliers from the rest of the data? This challenge is exacerbated by the steady growth in data set size [11] as new instruments push into new frontiers of parameter space, via improvements in temporal, spatial, and spectral resolution, or by the desire to "fuse" observations from different modalities and instruments into a larger-picture understanding of the same underlying phenomenon. Data clustering algorithms provide a variety of solutions for this task. They can generate summaries, locate outliers, compress data, identify dense or sparse regions of feature space, and build data models. It is useful to note up front that "clusters" in this context refer to groups of items within some descriptive feature space, not (necessarily) to "galaxy clusters" which are dense regions in physical space. The goal of this chapter is to survey a variety of data clustering methods, with an eye toward their applicability to astronomical data analysis. In addition to improving the individual researcher’s understanding of a given data set, clustering has led directly to scientific advances, such as the discovery of new subclasses of stars [14] and gamma-ray bursts (GRBs) [38]. All clustering algorithms seek to identify groups within a data set that reflect some observed, quantifiable structure. Clustering is traditionally an unsupervised approach to data analysis, in the sense that it operates without any direct guidance about which items should be assigned to which clusters. There has been a recent trend in the clustering literature toward supporting semisupervised or constrained

  12. Absolute cross sections of electron attachment to molecular clusters. Part II: Formation of (H2O) N - , (N2O) N - , and (N2) N -

    NASA Astrophysics Data System (ADS)

    Vostrikov, A. A.; Dubov, D. Yu.

    2006-12-01

    Absolute cross sections σ-( E, N) of electron attachment to clusters (H2O) N , (N2O) N , and (N2) N for varying electron energy E and cluster size N are measured by using crossed electron and cluster beams in a vacuum. Continua of σ-( E) are found that correlate well with the functions of electron impact excitation of molecules’ internal degrees of freedom. The electron is attached through its solvation in a cluster. In the formation of (H2O){/N -}, (N2O){/N -}, and (N2){/N -}, the curves σ-( N) have a well-defined threshold because of a rise in the electron thermalization and solvation probability with N. For (H2O)900, (N2O)350, and (N2)260 clusters at E = 0.2 eV, the energy losses by the slow electron in the cluster are estimated as 3.0 × 107, 2.7 × 107, and 6.0 × 105 eV/m, respectively. It is found that the growth of σ- with N is the fastest for (H2O) N and (N2) N clusters at E → 0 as a result of polarization capture of the s-electron. Specifically, at E = 0.1 eV and N = 260, σ- = 3.0 × 10-13 cm2 for H2O clusters, 8.0 × 10-14 cm2 for N2O clusters, and 1.4 × 10-15 cm2 for N2 clusters; at E = 11 eV, σ- = 9.0 × 10-16 cm2 for (H2O)200 clusters, 2.4 × 10-14 cm2 for (N2O)350 clusters, and 5.0 × 10-17 cm2 for (N2)260 clusters; finally, at E = 30 eV, σ- = 3.6 × 10-17 cm2 for (N2O)10 clusters and 3.0 × 10-17 cm2 for (N2)125 clusters.

  13. Identifying a Network of Brain Regions Involved in Aversion-Related Processing: A Cross-Species Translational Investigation

    PubMed Central

    Hayes, Dave J.; Northoff, Georg

    2011-01-01

    The ability to detect and respond appropriately to aversive stimuli is essential for all organisms, from fruit flies to humans. This suggests the existence of a core neural network which mediates aversion-related processing. Human imaging studies on aversion have highlighted the involvement of various cortical regions, such as the prefrontal cortex, while animal studies have focused largely on subcortical regions like the periaqueductal gray and hypothalamus. However, whether and how these regions form a core neural network of aversion remains unclear. To help determine this, a translational cross-species investigation in humans (i.e., meta-analysis) and other animals (i.e., systematic review of functional neuroanatomy) was performed. Our results highlighted the recruitment of the anterior cingulate cortex, the anterior insula, and the amygdala as well as other subcortical (e.g., thalamus, midbrain) and cortical (e.g., orbitofrontal) regions in both animals and humans. Importantly, involvement of these regions remained independent of sensory modality. This study provides evidence for a core neural network mediating aversion in both animals and humans. This not only contributes to our understanding of the trans-species neural correlates of aversion but may also carry important implications for psychiatric disorders where abnormal aversive behavior can often be observed. PMID:22102836

  14. The young stellar cluster [DBS2003] 157 associated with the H II region GAL 331.31-00.34

    NASA Astrophysics Data System (ADS)

    Pinheiro, M. C.; Abraham, Z.; Copetti, M. V. F.; Ortiz, R.; Falceta-Gonçalves, D. A.; Roman-Lopes, A.

    2012-07-01

    We report a study of the stellar content of the near-infrared (NIR) cluster [DBS2003] 157 embedded in the extended H II region GAL 331.31-00.34, which is associated with the IRAS source 16085-5138. JHK photometry was carried out in order to identify potential ionizing candidates, and the follow-up NIR spectroscopy allowed the spectral classification of some sources, including two O-type stars. A combination of NIR photometry and spectroscopy data was used to obtain the distance of these two stars, with the method of spectroscopic parallax: IRS 298 (O6 V, 3.35 ± 0.61 kpc) and IRS 339 (O9 V, 3.24 ± 0.56 kpc). Adopting the average distance of 3.29 ± 0.58 kpc and comparing the Lyman continuum luminosity of these stars with that required to account for the radio continuum flux of the H II region, we conclude that these two stars are the ionizing sources of GAL 331.31-00.34. Young stellar objects (YSOs) were searched by using our NIR photometry and mid-infrared (MIR) data from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) survey. The analysis of NIR and MIR colour-colour diagrams resulted in 47 YSO candidates. The GLIMPSE counterpart of IRAS 16085-5138, which presents IRAS colour indices compatible with an ultracompact H II region, has been identified. The analysis of its spectral energy distribution between 2 and ?m revealed that this source shows a spectral index α= 3.6 between 2 and ?m, which is typical of a YSO immersed in a protostellar envelope. Lower limits to the bolometric luminosity and the mass of the embedded protostar have been estimated as L= 7.7 × 103 L⊙ and M= 10 M⊙, respectively, which correspond to a B0-B1 V zero-age main sequence star. Based on observations carried at the Southern Observatory for Astrophysical Research (SOAR) observatory, a joint project of the Ministério de Ciência, Tecnologia e Inovação (MCTI) of the República Federativa do Brasil, the U.S. National Optical Astronomy Observatory (NOAO), the

  15. High resolution absorption cross sections in the transmission window region of the Schumann-Runge bands and Herzberg continuum of O2

    NASA Technical Reports Server (NTRS)

    Yoshino, K.; Esmond, J. R.; Cheung, A. S.-C.; Freeman, D. E.; Parkinson, W. H.

    1992-01-01

    Results are presented on measurements, conducted in the wavelength region 180-195 nm, and at different pressures of oxygen (between 2.5-760 torr) in order to separate the pressure-dependent absorption from the main cross sections, of the absorption cross sections of the Schumann-Runge bands in the window region between the rotational lines of S-R bands of O2. The present cross sections supersede the earlier published cross sections (Yoshino et al., 1983). The combined cross sections are presented graphically; they are available at wavenumber intervals of about 0.1/cm from the National Space Science Data Center. The Herzberg continuum cross sections are derived after subtracting calculated contributions from the Schumann-Runge bands. These are significantly smaller than any previous measurements.

  16. School Psychology in China (PRC), Hong Kong and Taiwan: A Cross-Regional Perspective

    ERIC Educational Resources Information Center

    Ding, Yi; Kuo, Yi-Lung; Van Dyke, Don C.

    2008-01-01

    Although China (People's Republic of China [PRC]), Hong Kong and Taiwan have many similarities in language, culture, values, Confucian traditions, family systems and other social-environmental variables, school psychological services in the three regions are distinctly different in both history and practice. Few studies in the psychology…

  17. Cross-scale dynamics of a regional urban system through time

    EPA Science Inventory

    In this work, we conducted an analysis of a regional urban system (southeastern United States) that has been the subject of research in the series of papers reviewed in the preceding sections. We used a U.S. census dataset incorporating the urbanized area (UA) definition. A UA co...

  18. Consumption of fruits and vegetables and associations with risk factors for non-communicable diseases in the Yangon region of Myanmar: a cross-sectional study

    PubMed Central

    Htet, Aung Soe; Stigum, Hein; Hla, Ne Yi; Hlaing, Hlaing Hlaing; Khaine, Ei Kay; Khaing, Win; Khant, Aung Kyaw; Khin, Naw Ohn Khin; Mauk, Kay Khine Aye; Moe, Ei Ei; Moe, Hla; Mon, Kyawt Kyawt; Mya, Kyaw Swa; Myint, Chomar Kaung; Myint, Cho Yi; Myint, Maung Maung; Myint, Ohnmar; New, Aye Aye; Oo, Ei Sanda; Oo, Khin Sandar; Pyone, Zin Zin; Soe, Yin Yin; Wai, Myint Myint; Win, Nilar; Bjertness, Espen

    2016-01-01

    Objectives To explore the intake of fruits and vegetables in the Yangon region, Myanmar, and to describe associations between intake of fruits and vegetables (FV) and established risk factors for non-communicable diseases. Design 2 cross-sectional studies, using the STEPs methodology. Setting Urban and rural areas of the Yangon region of Myanmar. Participants 1486, men and women, 25–74 years, were recruited through a multistage cluster sampling method. Institutionalised people, military personnel, Buddhist monks and nuns were not invited. Physically and mentally ill people were excluded. Results Mean intake of fruit was 0.8 (SE 0.1) and 0.6 (0.0) servings/day and of vegetables 2.2 (0.1) and 1.2 (0.1) servings/day, in urban and rural areas, respectively. Adjusted for included confounders (age, sex, location, income, education, smoking and low physical activity), men and women eating ≥2 servings of fruits and vegetables/day had lower odds than others of hypertriglyceridaemia (OR 0.72 (95% CI 0.56 to 0.94)). On average, women eating at least 2 servings of fruits and vegetables per day had cholesterol levels 0.28 mmol/L lower than the levels of other women. When only adjusted for sex and age, men eating at least 2 servings of fruits and vegetables per day had cholesterol levels 0.27 mmol/L higher than other men. Conclusions A high intake of FV was associated with lower odds of hypertriglyceridaemia among men and women. It was also associated with cholesterol levels, negatively among women and positively among men. PMID:27566634

  19. Use of cross-correlation measurements to investigate noise generating regions of a real jet engine and a model jet

    NASA Technical Reports Server (NTRS)

    Meecham, W. C.; Hurdle, P. M.

    1974-01-01

    Cross-correlations are reported of the jet static pressure fluctuations (as measured with a B and K microphone fitted with a nose cone), with the far-field radiated sound pressure. These measurements were made for various probe positions and a large number of far-field positions (at various angles). In addition, the tests were run for a number of different jet exit velocities. The measured, normalized cross-correlation functions vary between 0.004 and 0.155. These values depend upon the angular position of the far-field microphone, the jet exit Mach number, and the position of the probe. In addition, the cross-correlation technique was employed to study the symmetry of the far-field radiated sound about the jet axis. Third-octave analyses of both the probe signal and the far-field radiated sound were made. This is the first time correlation measurements have been made on a jet engine. In addition, a report is given on an extensive noise survey of a model jet. The correlations are related to sound source functions and jet source regions are discussed.

  20. Cross-Scale Analysis of the Region Effect on Vascular Plant Species Diversity in Southern and Northern European Mountain Ranges

    PubMed Central

    Lenoir, Jonathan; Gégout, Jean-Claude; Guisan, Antoine; Vittoz, Pascal; Wohlgemuth, Thomas; Zimmermann, Niklaus E.; Dullinger, Stefan; Pauli, Harald; Willner, Wolfgang; Grytnes, John-Arvid; Virtanen, Risto; Svenning, Jens-Christian

    2010-01-01

    Background The divergent glacial histories of southern and northern Europe affect present-day species diversity at coarse-grained scales in these two regions, but do these effects also penetrate to the more fine-grained scales of local communities? Methodology/Principal Findings We carried out a cross-scale analysis to address this question for vascular plants in two mountain regions, the Alps in southern Europe and the Scandes in northern Europe, using environmentally paired vegetation plots in the two regions (n = 403 in each region) to quantify four diversity components: (i) total number of species occurring in a region (total γ-diversity), (ii) number of species that could occur in a target plot after environmental filtering (habitat-specific γ-diversity), (iii) pair-wise species compositional turnover between plots (plot-to-plot β-diversity) and (iv) number of species present per plot (plot α-diversity). We found strong region effects on total γ-diversity, habitat-specific γ-diversity and plot-to-plot β-diversity, with a greater diversity in the Alps even towards distances smaller than 50 m between plots. In contrast, there was a slightly greater plot α-diversity in the Scandes, but with a tendency towards contrasting region effects on high and low soil-acidity plots. Conclusions/Significance We conclude that there are strong regional differences between coarse-grained (landscape- to regional-scale) diversity components of the flora in the Alps and the Scandes mountain ranges, but that these differences do not necessarily penetrate to the finest-grained (plot-scale) diversity component, at least not on acidic soils. Our findings are consistent with the contrasting regional Quaternary histories, but we also consider alternative explanatory models. Notably, ecological sorting and habitat connectivity may play a role in the unexpected limited or reversed region effect on plot α-diversity, and may also affect the larger-scale diversity components. For

  1. Triatoma dimidiata Infestation in Chagas Disease Endemic Regions of Guatemala: Comparison of Random and Targeted Cross-Sectional Surveys

    PubMed Central

    King, Raymond J.; Cordon-Rosales, Celia; Cox, Jonathan; Kitron, Uriel D.

    2011-01-01

    Background Guatemala is presently engaged in the Central America Initiative to interrupt Chagas disease transmission by reducing intradomiciliary prevalence of Triatoma dimidiata, using targeted cross-sectional surveys to direct control measures to villages exceeding the 5% control threshold. The use of targeted surveys to guide disease control programs has not been evaluated. Here, we compare the findings from the targeted surveys to concurrent random cross-sectional surveys in two primary foci of Chagas disease transmission in central and southeastern Guatemala. Methodology/Principal Findings Survey prevalences of T. dimidiata intradomiciliary infestation by village and region were compared. Univariate logistic regression was used to assess the use of risk factors to target surveys and to evaluate indicators associated with village level intradomiciliary prevalences >5% by survey and region. Multivariate logistic regression models were developed to assess the ability of random and targeted surveys to target villages with intradomiciliary prevalence exceeding the control threshold within each region. Regional prevalences did not vary by survey; however, village prevalences were significantly greater in random surveys in central (13.0% versus 8.7%) and southeastern (22.7% versus 6.9%) Guatemala. The number of significant risk factors detected did not vary by survey in central Guatemala but differed considerably in the southeast with a greater number of significant risk factors in the random survey (e.g. land surface temperature, relative humidity, cropland, grassland, tile flooring, and stick and mud and palm and straw walls). Differences in the direction of risk factor associations were observed between regions in both survey types. The overall discriminative capacity was significantly greater in the random surveys in central and southeastern Guatemala, with an area under the receiver-operator curve (AUC) of 0.84 in the random surveys and approximately 0.64 in the

  2. Recent Cross-Section Evaluations in the Resonance Region at the Oak Ridge National Laboratory

    SciTech Connect

    Leal, L.C.; Derrien, H.; Guber, K.H.; Sayer, R.; Larson, N.M.

    2005-05-24

    The intent of this work is to present the results and to describe the procedures utilized to evaluate 233U and 19F for criticality safety applications. The evaluation was done in the resolved resonance region using the reduced Reich-Moore R-matrix formalism. The resonance analysis was performed with the multilevel R-matrix code SAMMY, which utilizes the generalized least-squares technique based on Bayes theory.

  3. Colour gradients in cluster ellipticals at z ˜ 1.4: the hidden content of the galaxy central regions

    NASA Astrophysics Data System (ADS)

    Ciocca, F.; Saracco, P.; Gargiulo, A.; De Propris, R.

    2017-01-01

    We present F775W-F850LP (rest-frame UV-U) and F850LP-F160W (rest-frame U-R) colour gradients for a sample of 17 elliptical galaxies morphologically selected in the cluster XMMU J2235.3-2557 at z=1.39. We detected significant negative (redder inwards) U-R colour gradients in ˜70% of the galaxies and flat gradients for the remaining ones. On the other hand, the UV-U gradients are significant positive (bluer inwards) for ˜80% of the galaxies and flat for the remaining ones. Using stellar population synthesis models, we found that the behaviour of the two colour gradients cannot be simultaneously explained by a radial variation of age, metallicity and/or dust. The observed U-R gradients are consistent with a metallicity gradient (mean value ∇Z = -0.4) in agreement with the one observed in the local elliptical galaxies. The positive UV-U gradients cannot be explained with age or metallicity variations and imply an excess of UV emission toward the galaxies' central regions. This excess calls into question mechanisms able to efficiently produce UV emission. The data require either steady weak star formation (≲ 1 M⊙ yr-1) or a He-rich population in the cores of these galaxies in order to simultaneously reproduce both the colour gradients. On the contrary, the presence of a QSO cannot account for the observed UV excess on its own. We discuss these hypotheses on the basis of current observations and available models.

  4. Cross-sectional survey of the disaster preparedness of nurses across the Asia-Pacific region.

    PubMed

    Usher, Kim; Mills, Jane; West, Caryn; Casella, Evan; Dorji, Passang; Guo, Aimin; Koy, Virya; Pego, George; Phanpaseuth, Souksavanh; Phouthavong, Olaphim; Sayami, Jamuna; Lak, Muy Seang; Sio, Alison; Ullah, Mohammad Mofiz; Sheng, Yu; Zang, Yuli; Buettner, Petra; Woods, Cindy

    2015-12-01

    Healthcare workers who have received disaster preparedness education are more likely to report a greater understanding of disaster preparedness. However, research indicates that current nursing curricula do not adequately prepare nurses to respond to disasters. This is the first study to assess Asia-Pacific nurses' perceptions about their level of disaster knowledge, skills, and preparedness. A cross-sectional survey was conducted with 757 hospital and community nurses in seven Asia-Pacific countries. Data were collected using the modified Disaster Preparedness Evaluation Tool. Participants were found to have overall low-to-moderate levels of disaster knowledge, skills and preparedness, wherein important gaps were identified. A majority of the variance in disaster preparedness scores was located at the level of the individual respondent, not linked to countries or institutions. Multilevel random effects modelling identified disaster experience and education as significant factors of positive perceptions of disaster knowledge, skills, and management. The first step toward disaster preparedness is to ensure frontline health workers are able to respond effectively to disaster events. The outcomes of this study have important policy and education implications.

  5. Organization of the amplified type I interferon gene cluster and associated chromosome regions in the interphase nucleus of human osteosarcoma cells.

    PubMed

    Zeitz, Michael J; Marella, Narasimharao V; Malyavantham, Kishore S; Goetze, Sandra; Bode, Juergen; Raska, Ivan; Berezney, Ronald

    2009-01-01

    The organization of the amplified type I interferon (IFN) gene cluster and surrounding chromosomal regions was studied in the interphase cell nucleus of the human osteosarcoma cell line MG63. Rather than being arranged in a linear ladder-like array as in mitotic chromosomes, a cluster of approximately 15 foci was detected that was preferentially associated along the periphery of both the cell nucleus and a chromosome territory containing components of chromosomes 4, 8, and 9. Interspersed within the IFN gene foci were corresponding foci derived from amplified centromere 4 and 9 sequences. Other copies of chromosomes 4 and 8 were frequently detected in pairs or higher-order arrays lacking discrete borders between the chromosomes. In contrast, while chromosomes 4 and 8 in normal WI38 human fibroblast and osteoblast cells were occasionally found to associate closely, discrete boundaries were always detected between the two. DNA replication timing of the IFN gene cluster in early- to mid-S phase of WI38 cells was conserved in the amplified IFN gene cluster of MG63. Quantitative RT-PCR demonstrated a approximately 3-fold increase in IFN beta transcripts in MG63 compared with WI38 and RNA/DNA FISH experiments revealed 1-5 foci of IFN beta transcripts per cell with only approximately 5% of the cells showing foci within the highly amplified IFN gene cluster.

  6. Basal ganglia and thalamic input from neurons located within the ventral tier cell cluster region of the substantia nigra pars compacta in the rat.

    PubMed

    Cebrián, Carolina; Prensa, Lucía

    2010-04-15

    The most caudally located dopaminergic (DA) ventral tier neurons of the substantia nigra pars compacta (SNc) form typical cell clusters that are deeply embedded in the substantia nigra pars reticulata (SNr). Here we examine the efferent projections of 35 neurons located in the SNr region where these SNc cell clusters reside. The neuronal cell body was injected with biotinylated dextran amine so as to trace each complete axon in the sagittal or the coronal plane. Electrophysiological guidance guaranteed that the tracer was ejected among neurons displaying a typical SNc discharge pattern. Furthermore, double immunofluorescence and immunohistochemical labeling ensured that the tracer deposits were placed within the DA cell clusters. Three types of projection neurons occurred in the SNc ventral tier cell cluster region: type I neurons, projecting to basal ganglia; type II neurons, targeting both the basal ganglia and thalamus; and type III neurons, projecting only to the thalamus. The striatum was targeted by most of the type I and II neurons and the innervation reached both the striosome/subcallosal streak and matrix compartments. Many nigrostriatal fibers provided collaterals to the globus pallidus and, less frequently, to the subthalamic nucleus. At a thalamic level, type II and III neurons preferentially targeted the reticular, ventral posterolateral, and ventral medial nuclei. Our results reveal that the SNr region where DA ventral tier cell clusters reside harbors neurons projecting to the basal ganglia and/or the thalamus, thus suggesting that neurodegeneration of nigral neurons in Parkinson's disease might affect various extrastriatal basal ganglia structures and multiple thalamic nuclei.

  7. Evolution and expansion of the Mycobacterium tuberculosis PE and PPE multigene families and their association with the duplication of the ESAT-6 (esx) gene cluster regions

    PubMed Central

    Gey van Pittius, Nicolaas C; Sampson, Samantha L; Lee, Hyeyoung; Kim, Yeun; van Helden, Paul D; Warren, Robin M

    2006-01-01

    Background The PE and PPE multigene families of Mycobacterium tuberculosis comprise about 10% of the coding potential of the genome. The function of the proteins encoded by these large gene families remains unknown, although they have been proposed to be involved in antigenic variation and disease pathogenesis. Interestingly, some members of the PE and PPE families are associated with the ESAT-6 (esx) gene cluster regions, which are regions of immunopathogenic importance, and encode a system dedicated to the secretion of members of the potent T-cell antigen ESAT-6 family. This study investigates the duplication characteristics of the PE and PPE gene families and their association with the ESAT-6 gene clusters, using a combination of phylogenetic analyses, DNA hybridization, and comparative genomics, in order to gain insight into their evolutionary history and distribution in the genus Mycobacterium. Results The results showed that the expansion of the PE and PPE gene families is linked to the duplications of the ESAT-6 gene clusters, and that members situated in and associated with the clusters represent the most ancestral copies of the two gene families. Furthermore, the emergence of the repeat protein PGRS and MPTR subfamilies is a recent evolutionary event, occurring at defined branching points in the evolution of the genus Mycobacterium. These gene subfamilies are thus present in multiple copies only in the members of the M. tuberculosis complex and close relatives. The study provides a complete analysis of all the PE and PPE genes found in the sequenced genomes of members of the genus Mycobacterium such as M. smegmatis, M. avium paratuberculosis, M. leprae, M. ulcerans, and M. tuberculosis. Conclusion This work provides insight into the evolutionary history for the PE and PPE gene families of the mycobacteria, linking the expansion of these families to the duplications of the ESAT-6 (esx) gene cluster regions, and showing that they are composed of subgroups

  8. Proper motions and CCD-photometry of stars in the region of the open cluster NGC 1513

    NASA Astrophysics Data System (ADS)

    Frolov, V. N.; Jilinski, E. G.; Ananjevskaja, J. K.; Poljakov, E. V.; Bronnikova, N. M.; Gorshanov, D. L.

    2002-12-01

    The results of astrometric and photometric investigations of the poorly studied open cluster NGC 1513 are presented. The proper motions of 333 stars with a root-mean-square error of 1.9;mas yr-1 were obtained by means of the automated measuring complex ``Fantasy''. Eight astrometric plates covering the time interval of 101 years were measured and a total of 141 astrometric cluster members identified. BV CCD-photometry was obtained for stars in an area 17arcminx 17arcmin centered on the cluster. Altogether 33 stars were considered to be cluster members with high reliability by two criteria. The estimated age of NGC 1513 is 2.54x 108 years. Tables 2 and 3 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/396/125.

  9. Interaction of coherent VUV radiation with xenon clusters

    NASA Astrophysics Data System (ADS)

    Walters, Zachary; Santra, Robin; Greene, Chris H.

    2006-05-01

    When a short, intense laser pulse interacts with an atomic cluster, the atom-laser interaction is greatly enhanced by the high density of atoms within the cluster, while the finite size of the cluster prevents energy from escaping the interaction region. Thus hot, dense plasmas can form which can in turn alter the form of the laser-cluster interaction. We present a model of the laser-cluster interaction which takes atomic structure into account, using non-perturbative R-matrix techniques to calculate inverse bremsstrahlung and photoionization cross sections for Herman-Skillman atomic potentials. We describe the evolution of the cluster under the influence of the processes of inverse bremsstrahlung heating, photoionization, collisional ionization and recombination, and expansion of the cluster. We compare results with the experiments of Wabnitz et al [Nature 420, 482 (2002)] and Laarmann et al. [Phys. Rev. Lett. 95, 063402 (2005)].

  10. Molecular Cross-Talk between Nonribosomal Peptide Synthetase Carrier Proteins and Unstructured Linker Regions.

    PubMed

    Harden, Bradley J; Frueh, Dominique P

    2017-01-24

    Nonribosomal peptide synthetases (NRPSs) employ multiple domains separated by linker regions to incorporate substrates into natural products. During synthesis, substrates are covalently tethered to carrier proteins that translocate between catalytic partner domains. The molecular parameters that govern translocation and associated linker remodeling remain unknown. Here, we used NMR to characterize the structure, dynamics, and invisible states of a peptidyl carrier protein flanked by its linkers. We showed that the N-terminal linker stabilizes and interacts with the protein core while modulating dynamics at specific sites involved in post-translational modifications and/or domain interactions. The results detail the molecular communication between peptidyl carrier proteins and their linkers and could guide efforts in engineering NRPSs to obtain new pharmaceuticals.

  11. Informed Consent in cross-cultural perspective: clinical research in the Tibetan Autonomous Region, PRC.

    PubMed

    Adams, Vincanne; Miller, Suellen; Craig, Sienna; Sonam; Nyima; Droyoung; Le, Phuoc V; Varner, Micheal

    2007-12-01

    Procedures of Informed Consent are considered a high priority for international biomedical research. However, informed consent protocols are not necessarily transferable across cultural, national or ethnic groups. Recent debates identify the need for balancing ethical universals with practical and local conditions and paying attention to questions of cultural competence when it comes to the Informed Consent process for clinical biomedical research. This article reports on the results of a two-year effort to establish a culturally appropriate Informed Consent process for biomedical research in the Tibet Autonomous Region in the People's Republic of China. A team of Tibetan and American researchers, physicians, health professionals and medical anthropologists conducted the research. The Informed Consent was specifically for undertaking a triple-blind, double placebo-controlled randomized clinical trial of a Tibetan medicine compared with Misoprostol for reducing postpartum blood loss. The findings suggest greater need for flexibility and cooperation in establishing Informed Consent protocols across cultures and nations.

  12. PAPIN: A Fortran-IV program to calculate cross section probability tables, Bondarenko and transmission self-shielding factors for fertile isotopes in the unresolved resonance region

    SciTech Connect

    Munoz-Cobos, J.G.

    1981-08-01

    The Fortran IV code PAPIN has been developed to calculate cross section probability tables, Bondarenko self-shielding factors and average self-indication ratios for non-fissile isotopes, below the inelastic threshold, on the basis of the ENDF/B prescriptions for the unresolved resonance region. Monte-Carlo methods are utilized to generate ladders of resonance parameters in the unresolved resonance region, from average resonance parameters and their appropriate distribution functions. The neutron cross-sections are calculated by the single level Breit-Wigner (SLBW) formalism, with s, p and d-wave contributions. The cross section probability tables are constructed by sampling the Doppler-broadened cross sections. The various self-shielded factors are computed numerically as Lebesgue integrals over the cross section probability tables. The program PAPIN has been validated through extensive comparisons with several deterministic codes.

  13. Results of total cross section measurements for 197Au in the neutron energy region from 4 to 108 keV at GELINA

    NASA Astrophysics Data System (ADS)

    Sirakov, I.; Becker, B.; Capote, R.; Dupont, E.; Kopecky, S.; Massimi, C.; Schillebeeckx, P.

    2013-11-01

    Transmission measurements have been performed to determine the total cross section for neutron-induced reactions with 197Au in the energy region from 4keV to 108keV. The experiments were carried out at a 50m measurement station of the time-of-flight facility GELINA using a 6Li glass scintillator. The average total cross section as a function of neutron energy was derived after correcting the observed average transmission for cross section fluctuations due to resonance structures. The results have been compared with literature data and with the total cross section resulting from a dispersive coupled-channel optical model potential. The neutron strength function for s -wave neutrons and an orbital-independent scattering radius, together with their covariance matrix, have been derived in the neutron energy region between 4keV and 108keV through a parameterization of the total cross section based on a nuclear reaction theory.

  14. Characterization of divIVA and other genes located in the chromosomal region downstream of the dcw cluster in Streptococcus pneumoniae.

    PubMed

    Fadda, Daniela; Pischedda, Carla; Caldara, Fabrizio; Whalen, Michael B; Anderluzzi, Daniela; Domenici, Enrico; Massidda, Orietta

    2003-10-01

    We analyzed the chromosome region of Streptococcus pneumoniae located downstream of the division and cell wall (dcw) cluster that contains the homolog of the Bacillus subtilis cell division gene divIVA and some genes of unknown function. Inactivation of divIVA in S. pneumoniae resulted in severe growth inhibition and defects in cell shape, nucleoid segregation, and cell division. Inactivation of the ylm genes resulted in some morphological and/or division abnormalities, depending on the inactivated gene. Transcriptional analysis revealed a relationship between these genes and the ftsA and ftsZ cell division genes, also indicating that the connection between the dcw cluster and the divIVA region is more extensive than just chromosomal position and gene organization.

  15. The Elephant Trunk Nebula and the Trumpler 37 cluster: contribution of triggered star formation to the total population of an H II region

    NASA Astrophysics Data System (ADS)

    Getman, Konstantin V.; Feigelson, Eric D.; Sicilia-Aguilar, Aurora; Broos, Patrick S.; Kuhn, Michael A.; Garmire, Gordon P.

    2012-11-01

    Rich young stellar clusters produce H II regions whose expansion into the nearby molecular cloud is thought to trigger the formation of new stars. However, the importance of this mode of star formation is uncertain. This investigation seeks to quantify triggered star formation (TSF) in IC 1396A (aka the Elephant Trunk Nebula), a bright-rimmed cloud (BRC) on the periphery of the nearby giant H II region IC 1396 produced by the Trumpler 37 cluster. X-ray selection of young stars from Chandra X-ray Observatory data is combined with existing optical and infrared surveys to give a more complete census of the TSF population. Over 250 young stars in and around IC 1396A are identified; this doubles the previously known population. A spatio-temporal gradient of stars from the IC 1396A cloud towards the primary ionizing star HD 206267 is found. We argue that the TSF mechanism in IC 1396A is a radiation-driven implosion process persisting over several million years. Analysis of the X-ray luminosity and initial mass functions indicates that >140 stars down to 0.1 M⊙ were formed by TSF. Considering other BRCs in the IC 1396 H II region, we estimate the TSF contribution for the entire H II region exceeds 14-25 per cent today, and may be higher over the lifetime of the H II region. Such triggering on the periphery of H II regions may be a significant mode of star formation in the Galaxy.

  16. Cross layer design for optimised region of interest of ultrasound video data over mobile WiMAX.

    PubMed

    Debono, Carl J; Micallef, Brian W; Philip, Nada Y; Alinejad, Ali; Istepanian, Robert S H; Amso, Nazar N

    2012-11-01

    The application of advanced error concealment techniques applied as a post-process to conceal lost video information in error-prone channels, such as the wireless channel, demand additional processing at the receiver. This increases the delivery delay and needs more computational power. However, in general, only a small region within medical video is of interest to the physician and thus if only this area is considered, the number of computations can be curtailed. In this paper we present a technique whereby the Region of Interest (ROI) specified by the physician is used to delimit the area where the more complex concealment techniques are applied. A cross layer design approach in mobile WiMAX wireless communication environment is adopted in this paper to provide an optimized Quality of Experience (QoE) in the region that matters most to the mobile physician while relaxing the requirements in the background, ensuring real-time delivery. Results show that a diagnostically acceptable Peak Signal-to-Noise-Ratio (PSNR) of about 36 dB can still be achieved within reasonable decoding time.

  17. Cluster of differentiation 147 is a key molecule during hepatocellular carcinoma cell-hepatic stellate cell cross-talk in the rat liver.

    PubMed

    Ma, Tianyou; Wang, Zhilun; Yang, Zhantian; Chen, Jinghong

    2015-07-01

    The cross-talk between hepatocellular carcinoma (HCC) cells and activated hepatic stellate cells (HSCs) is considered to be important for modulating the biological behavior of tumor cells. However, the molecular links between inflammation and cancer in the activation of HSCs remain to be elucidated. The present study demonstrated that cluster of differentiation (CD)147 is a key molecule involved in the interaction between HCC cells and HSCs. The effects of conditioned medium from human HCC cells on the activation of the human HSC line, LX-2, were assessed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, western blotting and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Western blotting, RT-qPCR and gelatin zymography were also used to investigate the effects of CD147 on the activation of LX-2. The expression levels of α-smooth muscle actin (α-SMA) and CD147 were assessed in a co-culture system of LX-2 and FHCC-98 cells by immunofluorescence staining and immunoblotting. In hepatic tissues from a rat model of fibrosis, immunohistochemistry and immunoblotting were performed to detect the expression levels of α-SMA and CD147. Tumor-conditioned medium and CD147 promoted cell proliferation, activated LX-2 cells, increased the expression levels of α-SMA, collagen I and tissue inhibitor of metalloproteinase-1 (TIMP-1), and increased the secretion of matrix metalloproteinase (MMP)-2. The HSCs, which were induced in the co-culture system of HCC cells and HSCs exhibited marked expression levels of CD147. In the hepatic tissue of rat models of fibrosis induced by CCl4, marked expression levels of CD147 were observed in the activated HSCs. Therefore, CD147 promoted the activation of HSCs and was a key molecule during HCC cell-HSC cross-talk in the rat liver.

  18. Electronically excited states and visible region photodissociation spectroscopy of Aum+.Arn clusters (m=7-9): Molecular dimensionality transition?

    NASA Astrophysics Data System (ADS)

    Gloess, Alexia N.; Schneider, Holger; Weber, J. Mathias; Kappes, Manfred M.

    2008-03-01

    Photodissociation spectra were determined for Aum+ṡArn (m =7; n =0-3 and m =8,9; n =0,1) in the photon energy range of 2.14-3.02eV. Experimental data were compared with predictions of dipole allowed transitions using time-dependent density functional theory (TDDFT) as applied to cluster structures from both DFT (B3-LYP functional) and ab initio calculations at the MP2 level. Argon adduct formation does not significantly perturb the bare metal cluster core structure, but it does change the metal cluster spectrum for highly symmetric cluster structures. The photodissociation spectra are consistent with a transition from planar to three-dimensional gold cluster core geometries between m =7 and m =8 for both n =0 and 1. TDDFT predictions for favored isomers describe experimental absorption features to within ±0.25eV. We also discuss size-dependent trends in TDDFT transition energies for the lowest energy two- and three-dimensional structures of Aum+(m=3-9).

  19. Evaluated 182,183,184,186W Neutron Cross Sections and Covariances in the Resolved Resonance Region

    SciTech Connect

    Pigni, Marco T; Leal, Luiz C

    2015-01-01

    Oak Ridge National Laboratory (ORNL) has recently completed the resonance parameter evaluation of four tungsten isotopes, i.e., 182,183,184,186W, in the neutron energy range of thermal up to several keV. This nuclear data work was performed with support from the US Nuclear Criticality Safety Program (NCSP) in an effort to provide improved tungsten cross section and covariance data for criticality safety analyses. The evaluation methodology uses the Reich-Moore approximation of the R-matrix formalism of the code SAMMY to fit high-resolution measurements performed in 2010 and 2012 at the Geel linear accelerator facility (GELINA), as well as other experimental data sets on natural tungsten available in the EXFOR library. In the analyzed energy range, this work nearly doubles the resolved resonance region (RRR) present in the latest US nuclear data library ENDF/B-VII.1. In view of the interest in tungsten for distinct types of nuclear applications and the relatively homogeneous distribution of the isotopic tungsten—namely, 182W(26.5%), 183W(14.31%), 184W(30.64%), and 186W(28.43%) - the completion of these four evaluations represents a significant contribution to the improvement of the ENDF library. This paper presents an overview of the evaluated resonance parameters and related covariances for total and capture cross sections on the four tungsten isotopes.

  20. Design of Extraction Line Optics for the ILCInteraction Regions with 20 mrad and 2 mrad Crossing Angles

    SciTech Connect

    Nosochkov, Y.; Moffeit, K.; Seryi, A.; Spencer, C.; Wood, M.; Parker, B.; Appleby, R.; Angal-Kalinin, D.; /Daresbury

    2005-07-27

    The studies of the ILC extraction line design have been carried out by the SLAC-BNL-UK-France task force collaboration. In this paper, we describe two options of the extraction optics for the 20 mrad horizontal crossing angle in the Interaction Region (IR), and one option of the 2 mrad extraction optics. The main functions of the extraction line are to transport the primary beam and beamstrahlung photons to dumps with acceptable beam loss, and to provide the necessary optics for beam diagnostics. The presented 20 mrad and 2 mrad optics are designed for up to 1 TeV and 0.5 TeV Center of Mass (CM) energy, respectively. The upgrade of this 2 mrad design to 1 TeV CM and a separate version of the 2 mrad design are presented in a separate report [1].

  1. Use of Traditional and Complementary Medicine as Self-Care Strategies in Community Health Centers: Cross-Sectional Study in Urban Pearl River Delta Region of China.

    PubMed

    Chung, Vincent C H; Wong, Samuel Y S; Wang, Harry H X; Wong, Martin C S; Wei, Xiaolin; Wang, Jiaji; Liu, Siya; Ho, Robin S T; Yu, Ellen L M; Griffiths, Sian M

    2016-06-01

    In China, Community Health Centers (CHCs) are major providers of primary care services, but their potential in empowering patients' self-management capacity has not been assessed. This study aims to describe self-care practice patterns amongst CHC attendees in urban China.In this cross-sectional quantitative study, 3360 CHC patients from 6 cities within the Pearl Delta Region were sampled using multistage cluster sampling.Thirty-seven per cent had used with over-the-counter Chinese herbal medicines (OTC CHMs) in the past year and majority of respondents found OTC CHMs effective. OTC CHMs were more popular amongst those who needed to pay out of pocket for CHC services. Less than 10% used vitamins and minerals, and those with a lower socioeconomic background have a higher propensity to consume. Although doubts on their usefulness are expressed, their use by the vulnerable population may reflect barriers to access to conventional health care, cultural affinity, or a defense against negative consequences of illnesses. About 25% performed physical exercise, but the prevalence is lower amongst women and older people. Taiji seems to be an alternative for these populations with promising effectiveness, but overall only 6% of CHC attendees participated.These results suggest that CHCs should start initiatives in fostering appropriate use of OTC CHM, vitamins, and minerals. Engaging community pharmacists in guiding safe and effective use of OTC CHM amongst the uninsured is essential given their low accessibility to CHC services. Prescription of Taiji instead of physical exercises to women and older people could be more culturally appropriate, and the possibility of including this as part of the CHC services worth further exploration.

  2. Defining regions of interest using cross-frequency coupling in extratemporal lobe epilepsy patients

    NASA Astrophysics Data System (ADS)

    Guirgis, Mirna; Chinvarun, Yotin; del Campo, Martin; Carlen, Peter L.; Bardakjian, Berj L.

    2015-04-01

    Objective. Clinicians identify seizure onset zones (SOZs) for resection in an attempt to localize the epileptogenic zone (EZ), which is the cortical tissue that is indispensible for seizure generation. An automated system is proposed to objectively localize this EZ by identifying regions of interest (ROIs). Methods. Intracranial electroencephalogram recordings were obtained from seven patients presenting with extratemporal lobe epilepsy and the interaction between neuronal rhythms in the form of phase-amplitude coupling was investigated. Modulation of the amplitude of high frequency oscillations (HFOs) by the phase of low frequency oscillations was measured by computing the modulation index (MI). Delta- (0.5-4 Hz) and theta- (4-8 Hz) modulation of HFOs (30-450 Hz) were examined across the channels of a 64-electrode subdural grid. Surrogate analysis was performed and false discovery rates were computed to determine the significance of the modulation observed. Mean MI values were subjected to eigenvalue decomposition (EVD) and channels defining the ROIs were selected based on the components of the eigenvector corresponding to the largest eigenvalue. ROIs were compared to the SOZs identified by two independent neurologists. Global coherence values were also computed. Main results. MI was found to capture the seizure in time for six of seven patients and identified ROIs in all seven. Patients were found to have a poorer post-surgical outcome when the number of EVD-selected channels that were not resected increased. Moreover, in patients who experienced a seizure-free outcome (i.e., Engel Class I) all EVD-selected channels were found to be within the resected tissue or immediately adjacent to it. In these Engel Class I patients, delta-modulated HFOs were found to identify more of the channels in the resected tissue compared to theta-modulated HFOs. However, for the Engel Class IV patient, the delta-modulated HFOs did not identify any of the channels in the resected

  3. Patient experience of different regional models of urgent and emergency care: a cross-sectional survey study

    PubMed Central

    Foley, Conor; Droog, Elsa; Boyce, Maria; Healy, Orla; Browne, John

    2017-01-01

    Objectives To compare user experiences of 8 regional urgent and emergency care systems in the Republic of Ireland, and explore potential avenues for improvement. Design A cross-sectional survey. Setting Several distinct models of urgent and emergency care operate in Ireland, as system reconfiguration has been implemented in some regions but not others. The Urgent Care System Questionnaire was used to explore service users' experiences with urgent and emergency care. Linear regression and logistic regression were used to detect regional variation in each of the 3 domains and overall ratings of care. Participants A nationally representative sample (N=8002) of the general population was contacted by telephone, yielding 1205 participants who self-identified as having used urgent and emergency care services in the previous 3 months. Main outcome measures Patient experience was assessed across 3 domains: entry into the system, progress through the system and patient convenience of the system. Participants were also asked to provide an overall rating of the care they received. Results Service users in Dublin North East gave lower ratings on the entry into the system scale than those in Dublin South (adjusted mean difference=−0.18; 95% CI −0.35 to −0.10; p=0.038). For overall ratings of care, service users in the Mid-West were less likely than those in Dublin North East to give an excellent rating (adjusted OR 0.57; 95% CI 0.35 to 0.92; p=0.022). Survey items relating to communication, and consideration of patients' needs were comparatively poorly rated. The use of public emergency departments and out-of-hours general practice care was associated with poorer patient experiences. Conclusions No consistent relationship was found between the type of urgent and emergency care model in different regions and patient experience. Scale-level data may not offer a useful metric for exploring the impact of system-level service change. PMID:28320790

  4. Cluster bulleticity

    NASA Astrophysics Data System (ADS)

    Massey, Richard; Kitching, Thomas; Nagai, Daisuke

    2011-05-01

    The unique properties of dark matter are revealed during collisions between clusters of galaxies, such as the bullet cluster (1E 0657-56) and baby bullet (MACS J0025-12). These systems provide evidence for an additional, invisible mass in the separation between the distributions of their total mass, measured via gravitational lensing, and their ordinary 'baryonic' matter, measured via its X-ray emission. Unfortunately, the information available from these systems is limited by their rarity. Constraints on the properties of dark matter, such as its interaction cross-section, are therefore restricted by uncertainties in the individual systems' impact velocity, impact parameter and orientation with respect to the line of sight. Here we develop a complementary, statistical measurement in which every piece of substructure falling into every massive cluster is treated as a bullet. We define 'bulleticity' as the mean separation between dark matter and ordinary matter, and we measure the signal in hydrodynamical simulations. The phase space of substructure orbits also exhibits symmetries that provide an equivalent control test. Any detection of bulleticity in real data would indicate a difference in the interaction cross-sections of baryonic and dark matter that may rule out hypotheses of non-particulate dark matter that are otherwise able to model individual systems. A subsequent measurement of bulleticity could constrain the dark matter cross-section. Even with conservative estimates, the existing Hubble Space Telescope archive should yield an independent constraint tighter than that from the bullet cluster. This technique is then trivially extendable to and benefits enormously from larger, future surveys.

  5. Cluster Analysis: A New Tool for Understanding the Role of the Inner City in a Regional Economy.

    ERIC Educational Resources Information Center

    Melnick, Rob; Waits, Mary Jo; Rex, Tom

    1998-01-01

    Research in two inner-city areas of Phoenix (Arizona) and its surrounding suburbs documents the importance of analyzing a metropolitan area's economy from the perspective of industry clusters before determining economic development policies and strategies for urban revitalization. In addition, the project reveals lessons about the role of…

  6. Effect of Primary Dendrite Orientation on Stray Grain Formation in Cross-Section Change Region During the Directional Solidification of Ni-Based Superalloy

    NASA Astrophysics Data System (ADS)

    Xuan, Weidong; Li, Chuantao; Zhao, Dengke; Wang, Baojun; Li, Chuanjun; Ren, Zhongming; Zhong, Yunbo; Li, Xi; Cao, Guanghui

    2017-02-01

    The effect of primary dendrite orientation on stray grain formation in a cross-section change region during the directional solidification of Ni-based superalloy is investigated through both experimental observations and numerical simulation. The results clearly show that the orientation of primary dendrite affects the formation of stray grains in the cross-section change region. It is observed that, for the primary dendrite without misorientation, no stray grain is formed in the cross-section change region; for the primary dendrite with a moderate misorientation (15 deg), stray grains are formed only on the side converging from the mold wall in the cross-section change region. When the misorientation is 25 deg, stray grains are formed on both the side converging from the mold wall and the side diverging from the mold wall in the cross-section change region (the converging side and the diverging side for short). The simulation results are in accordance with experimental results. Furthermore, the correlation among factors such as stray grain formation, primary dendrite orientation, and withdrawal velocity has been analyzed. The mechanism of stray grain formation in various oriented primary dendrites is discussed.

  7. Towards the high-accuracy determination of the 238U fission cross section at the threshold region at CERN - n_TOF

    NASA Astrophysics Data System (ADS)

    Diakaki, M.; Audouin, L.; Berthoumieux, E.; Calviani, M.; Colonna, N.; Dupont, E.; Duran, I.; Gunsing, F.; Leal-Cidoncha, E.; Le Naour, C.; Leong, L. S.; Mastromarco, M.; Paradela, C.; Tarrio, D.; Tassan-Got, L.; Aerts, G.; Altstadt, S.; Alvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Badurek, G.; Barbagallo, M.; Baumann, P.; Becares, V.; Becvar, F.; Belloni, F.; Berthier, B.; Billowes, J.; Boccone, V.; Bosnar, D.; Brugger, M.; Calvino, F.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Cennini, P.; Cerutti, F.; Chiaveri, E.; Chin, M.; Cortes, G.; Cortes-Giraldo, M. A.; Cosentino, L.; Couture, A.; Cox, J.; David, S.; Dillmann, I.; Domingo-Pardo, C.; Dressler, R.; Dridi, W.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Finocchiaro, P.; Fraval, K.; Fujii, K.; Furman, W.; Ganesan, S.; Garcia, A. R.; Giubrone, G.; Gomez-Hornillos, M. B.; Goncalves, I. F.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Gurusamy, P.; Haight, R.; Heil, M.; Heinitz, S.; Igashira, M.; Isaev, S.; Jenkins, D. G.; Jericha, E.; Kadi, Y.; Kaeppeler, F.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Ketlerov, V.; Kivel, N.; Kokkoris, M.; Konovalov, V.; Krticka, M.; Kroll, J.; Lampoudis, C.; Langer, C.; Lederer, C.; Leeb, H.; Lo Meo, S.; Losito, R.; Lozano, M.; Manousos, A.; Marganiec, J.; Martinez, T.; Marrone, S.; Massimi, C.; Mastinu, P.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Mingrone, F.; Mirea, M.; Mondelaers, W.; Moreau, C.; Mosconi, M.; Musumarra, A.; O'Brien, S.; Pancin, J.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perkowski, J.; Perrot, L.; Pigni, M. T.; Plag, R.; Plompen, A.; Plukis, L.; Poch, A.; Pretel, C.; Praena, J.; Quesada, J.; Rauscher, T.; Reifarth, R.; Riego, A.; Roman, F.; Rudolf, G.; Rubbia, C.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Sarmento, R.; Saxena, A.; Schillebeeckx, P.; Schmidt, S.; Schumann, D.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tavora, L.; Terlizzi, R.; Tsinganis, A.; Valenta, S.; Vannini, G.; Variale, V.; Vaz, P.; Ventura, A.; Versaci, R.; Vermeulen, M. J.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Wallner, A.; Walter, S.; Ware, T.; Weigand, M.; Weiß, C.; Wiesher, M.; Wisshak, K.; Wright, T.; Zugec, P.

    2016-03-01

    The 238U fission cross section is an international standard beyond 2 MeV where the fission plateau starts. However, due to its importance in fission reactors, this cross-section should be very accurately known also in the threshold region below 2 MeV. The 238U fission cross section has been measured relative to the 235U fission cross section at CERN - n_TOF with different detection systems. These datasets have been collected and suitably combined to increase the counting statistics in the threshold region from about 300 keV up to 3 MeV. The results are compared with other experimental data, evaluated libraries, and the IAEA standards.

  8. Cross-correlation of SDSS DR7 Quasars and DR10 BOSS Galaxies: The Weak Luminosity Dependence of Quasar Clustering at z ~ 0.5

    NASA Astrophysics Data System (ADS)

    Shen, Yue; McBride, Cameron K.; White, Martin; Zheng, Zheng; Myers, Adam D.; Guo, Hong; Kirkpatrick, Jessica A.; Padmanabhan, Nikhil; Parejko, John K.; Ross, Nicholas P.; Schlegel, David J.; Schneider, Donald P.; Streblyanska, Alina; Swanson, Molly E. C.; Zehavi, Idit; Pan, Kaike; Bizyaev, Dmitry; Brewington, Howard; Ebelke, Garrett; Malanushenko, Viktor; Malanushenko, Elena; Oravetz, Daniel; Simmons, Audrey; Snedden, Stephanie

    2013-12-01

    We present the measurement of the two-point cross-correlation function (CCF) of 8198 Sloan Digital Sky Survey Data Release 7 quasars and 349,608 Data Release 10 CMASS galaxies from the Baryonic Oscillation Spectroscopic Survey at 0.3 < z < 0.9. The CCF can be reasonably well fit by a power-law model ξQG(r) = (r/r 0)-γ on projected scales of rp = 2-25 h -1 Mpc with r 0 = 6.61 ± 0.25 h -1 Mpc and γ = 1.69 ± 0.07. We estimate a quasar linear bias of bQ = 1.38 ± 0.10 at langzrang = 0.53 from the CCF measurements, which corresponds to a characteristic host halo mass of ~4 × 1012 h -1 M ⊙, compared with a ~1013 h -1 M ⊙ characteristic host halo mass for CMASS galaxies. Based on the clustering measurements, most quasars at \\bar{z}\\sim 0.5 are not the descendants of their higher luminosity counterparts at higher redshift, which would have evolved into more massive and more biased systems at low redshift. We divide the quasar sample in luminosity and constrain the luminosity dependence of quasar bias to be dbQ /dlog L = 0.20 ± 0.34 or 0.11 ± 0.32 (depending on different luminosity divisions) for quasar luminosities -23.5 > Mi (z = 2) > -25.5, implying a weak luminosity dependence of clustering for luminous quasars at \\bar{z}\\sim 0.5. We compare our measurements with theoretical predictions, halo occupation distribution (HOD) models, and mock catalogs. These comparisons suggest that quasars reside in a broad range of host halos. The host halo mass distributions significantly overlap with each other for quasars at different luminosities, implying a poor correlation between halo mass and instantaneous quasar luminosity. We also find that the quasar HOD parameterization is largely degenerate such that different HODs can reproduce the CCF equally well, but with different satellite fractions and host halo mass distributions. These results highlight the limitations and ambiguities in modeling the distribution of quasars with the standard HOD approach.

  9. Cross-correlation of SDSS DR7 quasars and DR10 BOSS galaxies: The weak luminosity dependence of quasar clustering at z ∼ 0.5

    SciTech Connect

    Shen, Yue; McBride, Cameron K.; Swanson, Molly E. C.; White, Martin; Kirkpatrick, Jessica A.; Ross, Nicholas P.; Schlegel, David J.; Zheng, Zheng; Myers, Adam D.; Guo, Hong; Zehavi, Idit; Padmanabhan, Nikhil; Parejko, John K.; Schneider, Donald P.; Streblyanska, Alina; Pan, Kaike; Bizyaev, Dmitry; Brewington, Howard; Ebelke, Garrett; Malanushenko, Viktor; and others

    2013-12-01

    We present the measurement of the two-point cross-correlation function (CCF) of 8198 Sloan Digital Sky Survey Data Release 7 quasars and 349,608 Data Release 10 CMASS galaxies from the Baryonic Oscillation Spectroscopic Survey at 0.3 < z < 0.9. The CCF can be reasonably well fit by a power-law model ξ{sub QG}(r) = (r/r {sub 0}){sup –γ} on projected scales of r{sub p} = 2-25 h {sup –1} Mpc with r {sub 0} = 6.61 ± 0.25 h {sup –1} Mpc and γ = 1.69 ± 0.07. We estimate a quasar linear bias of b{sub Q} = 1.38 ± 0.10 at (z) = 0.53 from the CCF measurements, which corresponds to a characteristic host halo mass of ∼4 × 10{sup 12} h {sup –1} M {sub ☉}, compared with a ∼10{sup 13} h {sup –1} M {sub ☉} characteristic host halo mass for CMASS galaxies. Based on the clustering measurements, most quasars at z-bar ∼0.5 are not the descendants of their higher luminosity counterparts at higher redshift, which would have evolved into more massive and more biased systems at low redshift. We divide the quasar sample in luminosity and constrain the luminosity dependence of quasar bias to be db{sub Q} /dlog L = 0.20 ± 0.34 or 0.11 ± 0.32 (depending on different luminosity divisions) for quasar luminosities –23.5 > M{sub i} (z = 2) > –25.5, implying a weak luminosity dependence of clustering for luminous quasars at z-bar ∼0.5. We compare our measurements with theoretical predictions, halo occupation distribution (HOD) models, and mock catalogs. These comparisons suggest that quasars reside in a broad range of host halos. The host halo mass distributions significantly overlap with each other for quasars at different luminosities, implying a poor correlation between halo mass and instantaneous quasar luminosity. We also find that the quasar HOD parameterization is largely degenerate such that different HODs can reproduce the CCF equally well, but with different satellite fractions and host halo mass distributions. These results highlight the limitations

  10. THE SPATIAL CLUSTERING OF ROSAT ALL-SKY SURVEY AGNs. II. HALO OCCUPATION DISTRIBUTION MODELING OF THE CROSS-CORRELATION FUNCTION

    SciTech Connect

    Miyaji, Takamitsu; Aceves, Hector; Krumpe, Mirko; Coil, Alison L.

    2011-01-10

    This is the second paper of a series that reports on our investigation of the clustering properties of active galactic nuclei (AGNs) in the ROSAT All-Sky Survey (RASS) through cross-correlation functions (CCFs) with Sloan Digital Sky Survey (SDSS) galaxies. In this paper, we apply the Halo Occupation Distribution (HOD) model to the CCFs between the RASS broad-line AGNs with SDSS luminous red galaxies (LRGs) in the redshift range 0.16 < z < 0.36 that was calculated in Paper I. In our HOD modeling approach, we use the known HOD of LRGs and constrain the HOD of the AGNs by a model fit to the CCF. For the first time, we are able to go beyond quoting merely a 'typical' AGN host halo mass, M{sub h}, and model the full distribution function of AGN host dark matter halos. In addition, we are able to determine the large-scale bias and the mean M{sub h} more accurately. We explore the behavior of three simple HOD models. Our first model (Model A) is a truncated power-law HOD model in which all AGNs are satellites. With this model, we find an upper limit to the slope ({alpha}) of the AGN HOD that is far below unity. The other two models have a central component, which has a step function form, where the HOD is constant above a minimum mass, without (Model B) or with (Model C) an upper mass cutoff, in addition to the truncated power-law satellite component, similar to the HOD that is found for galaxies. In these two models we find that the upper limits on {alpha} are still below unity, with {alpha} {approx}< 0.95 and {alpha} {approx}< 0.84 for Models B and C, respectively. Our analysis suggests that the satellite AGN occupation increases slower than, or may even decrease with, M{sub h}, in contrast to the satellite HODs of luminosity-threshold samples of galaxies, which, in contrast, grow approximately as (N{sub s}) {proportional_to} M{sup {alpha}}{sub h} with {alpha} {approx} 1. These results are consistent with observations that the AGN fraction in groups and clusters

  11. Effects of radiation and turbulence on the diabatic heating and water budget of the stratiform region of a tropical cloud cluster

    NASA Technical Reports Server (NTRS)

    Churchill, Dean D.; Houze, Robert A., Jr.

    1991-01-01

    A twi-dimensional kinematic model has been used to diagnose the thermodynamic, water vapor, and hydrometeor fields of the stratiform clouds associated with a mesoscale tropical cloud cluster. The model incorporates ice- and water-cloud microphysics, visible and infrared radiation, and convective adjustment. It is intended to determine the relative contributions of radiation, mycrophysics, and turbulence to diabatic heating, and the effects that radiation has on the water budget of the cluster in the absence of dynamical interactions. The model has been initialized with thermodynamic fields and wind velocities diagnosed from a GATE tropical squall line. It is found that radiation does not directly affect the water budget of the stratiform region, and any radiative effect on hydrometeors must involve interaction with dynamics.

  12. THE NEXT GENERATION VIRGO CLUSTER SURVEY. X. PROPERTIES OF ULTRA-COMPACT DWARFS IN THE M87, M49, AND M60 REGIONS

    SciTech Connect

    Liu, Chengze; Peng, Eric W.; Zhang, Hong-Xin; Côté, Patrick; Ferrarese, Laura; Gwyn, Stephen; Blakeslee, John P.; Jordán, Andrés; Muñoz, Roberto P.; Puzia, Thomas H.; Mihos, J. Christopher; Lançon, Ariane; Cuillandre, Jean-Charles; Durrell, Patrick R. E-mail: peng@pku.edu.cn; and others

    2015-10-10

    We use imaging from the Next Generation Virgo cluster Survey (NGVS) to present a comparative study of ultra-compact dwarf (UCD) galaxies associated with three prominent Virgo sub-clusters: those centered on the massive red-sequence galaxies M87, M49, and M60. We show how UCDs can be selected with high completeness using a combination of half-light radius and location in color–color diagrams (u*iK{sub s} or u*gz). Although the central galaxies in each of these sub-clusters have nearly identical luminosities and stellar masses, we find large differences in the sizes of their UCD populations, with M87 containing ∼3.5 and 7.8 times more UCDs than M49 and M60, respectively. The relative abundance of UCDs in the three regions scales in proportion to sub-cluster mass, as traced by X-ray gas mass, total gravitating mass, number of globular clusters (GCs), and number of nearby galaxies. We find that the UCDs are predominantly blue in color, with ∼85% of the UCDs having colors similar to blue GCs and stellar nuclei of dwarf galaxies. We present evidence that UCDs surrounding M87 and M49 may follow a morphological sequence ordered by the prominence of their outer, low surface brightness envelope, ultimately merging with the sequence of nucleated low-mass galaxies, and that envelope prominence correlates with distance from either galaxy. Our analysis provides evidence that tidal stripping of nucleated galaxies is an important process in the formation of UCDs.

  13. Waveforms clustering and single-station location of microearthquake multiplets recorded in the northern Sicilian offshore region

    NASA Astrophysics Data System (ADS)

    D'Alessandro, Antonino; Mangano, Giorgio; D'Anna, Giuseppe; Luzio, Dario

    2013-09-01

    In 2009 December, the OBSLab-INGV (Istituto Nazionale di Geofisica e Vulcanologia) deployed an Ocean Bottom Seismometer with Hydrophone (OBS/H) near the epicentral area of the main shock of the Palermo seismic sequence of 2002. The monitoring activity had a total duration of about 8 months. During this experiment, the OBS/H recorded 247 very local microearthquakes, whose local magnitude is between -0.5 and 2.5 and TS - TP delay time between 0.2 and 5 s, almost all of which were undetected by the Italian National Seismic Network. This local microseismicity has been analysed using an innovative clustering technique that exploits the similarity between the waveforms generated by different events. The clustering technique implemented, based on hierarchical agglomerative algorithms, nearest neighbour technique and dendrogram representation, allowed us to identify nine distinct multiplets characterized by a high degree of similarity between the waveforms. The microevents were located through an improved single-station location (SSL) technique based on the polarization analysis of the 3C signals and on the estimation of the TS - TP time. In the new SSL technique, an unbiased covariance matrix was defined and a ray tracer-based determination of the epicentral distance and hypocentral depth was proposed. All the multiplets were generated by events with hypocentres that were very close to each other. However, not all the identified clusters are also clustered in the time-magnitude domain. It was also observed that some multiplets have clouds of hypocentres overlapping each other. These clusters, indistinguishable without the application of a waveforms clustering technique, show differences in the waveforms that must be attributed to differences in the focal mechanisms which generated the waveforms. The local seismic events recorded are typical of a seismicity generated by a volume characterized by a highly complex fracturing pattern and by an important role in the dynamics

  14. Evaluation of Neutron Capture Cross Sections and Covariances on 99Tc and 129I in the keV Energy Region

    NASA Astrophysics Data System (ADS)

    Iwamoto, Nobuyuki

    2016-03-01

    Neutron capture cross sections and covariances on radioactive 99Tc and 129I have been required for developing environmental load-reducing technology. Their evaluation was performed by using nuclear reaction calculation code CCONE and Baysian code KALMAN with data assumed on the basis of measured data. The obtained total and capture cross sections are in good agreement with the measured data. The resulting uncertainties of capture cross section were 12-18% and 20-29% for 99Tc and 129I, respectively, in the keV energy region.

  15. A brain-specific gene cluster isolated from the region of the mouse obesity locus is expressed in the adult hypothalamus and during mouse development

    SciTech Connect

    Laig-Webster, M.; Lim, M.E.; Chehab, F.F.

    1994-09-01

    The molecular defect underlying an autosomal recessive form of genetic obesity in a classical mouse model C57 BL/6J-ob/ob has not yet been elucidated. Whereas metabolic and physiological disturbances such as diabetes and hypertension are associated with obesity, the site of expression and the nature of the primary lesion responsible for this cascade of events remains elusive. Our efforts aimed at the positional cloning of the ob gene by YAC contig mapping and gene identification have resulted in the cloning of a brain-specific gene cluster from the ob critical region. The expression of this gene cluster is remarkably complex owing to the multitude of brain-specific mRNA transcripts detected on Northern blots. cDNA cloning of these transcripts suggests that they are expressed from different genes as well as by alternate splicing mechanisms. Furthermore, the genomic organization of the cluster appears to consist of at least two identical promoters displaying CpG islands characteristic of housekeeping genes, yet clearly involving tissue-specific expression. Sense and anti-sense synthetic RNA probes were derived from a common DNA sequence on 3 cDNA clones and hybridized to 8-16 days mouse embryonic stages and mouse adult brain sections. Expression in development was noticeable as of the 11th day of gestation and confined to the central nervous system mainly in the telencephalon and spinal cord. Coronal and sagittal sections of the adult mouse brain showed expression only in 3 different regions of the brain stem. In situ hybridization to mouse hypothalamus sections revealed the presence of a localized and specialized group of cells expressing high levels of mRNA, suggesting that this gene cluster may also be involved in the regulation of hypothalamic activities. The hypothalamus has long been hypothesized as a primary candidate tissue for the expression of the obesity gene mainly because of its well-established role in the regulation of energy metabolism and food intake.

  16. Nonthermal Emission from Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Storm, Emma

    Galaxy clusters are the most massive gravitationally-bound objects in the universe. The bulk of the mass in a cluster is dark matter, while the dominant baryonic component is a thermal, X-ray emitting plasma. Radio observations of diffuse synchrotron emission indicate that galaxy clusters host a population of cosmic rays; however, the nature of this nonthermal component is not well-understood. In this dissertation, I investigate three sources of nonthermal emission in galaxy clusters. The first is star formation in galaxies, which is correlated to gamma-ray emission. I derive lower limits on the gamma-ray emission for nearby clusters by considering the emission from star formation in cluster galaxies. These lower limits sit about an order of magnitude below current upper limits on gamma rays in clusters and will be an important contributor to gamma-ray emission as upper limits improve over time. Dark matter annihilation, which produces relativistic particles that can result in a broad spectrum of emission in cluster environments, is another source of nonthermal emission. I use nondetections and marginal detections of diffuse radio emission in clusters to constrain dark matter annihilation. I derive limits on the annihilation cross section that are competitive with limits from the nondetection of gamma rays in clusters and show that the best objects for study in the radio are different than those in gamma rays, indicating that dark matter searches in the radio can be complementary to searches in other energy bands. I also investigate the cosmic ray population in the merging cluster A2319, which hosts a previously detected radio halo. I present new observations which reveal a two-component radio halo: a 2 Mpc region that extends far past the observable X-ray emission, and an 800 kpc "core" that is bounded by the X-ray cold front. I speculate on the origins of this structure, and show that a hadronic origin for this radio halo is disfavored. Finally, I discuss current

  17. Interaction of Coherent VUV Radiation with Xenon Clusters

    NASA Astrophysics Data System (ADS)

    Walters, Zachary; Santra, Robin

    2005-05-01

    The interaction of atomic clusters with short, intense pulses of laser light to form extremely hot, dense plasmas has attracted extensive experimental and theoretical interest. The high density of atoms within the cluster greatly enhances the atom-laser interaction, while the finite size of the cluster prevents energy from escaping the interaction region. A model of the laser-cluster interaction is presented which uses non-perturbative R-matrix techniques to calculate inverse bremsstrahlung and photoionization cross sections for Herman-Skillman atomic potentials. We describe the evolution of the cluster under the influence of the processes of inverse bremsstrahlung heating, photoionization, collisional ionization and recombination, and expansion of the cluster. Results are compared with the Hamburg experiment of Wabnitz et al [Nature 420, 482 (2002)]. This work was supported by the Department of Energy, Office of Science.

  18. Diversity, evolution, and functionality of clustered regularly interspaced short palindromic repeat (CRISPR) regions in the fire blight pathogen Erwinia amylovora.

    PubMed

    Rezzonico, Fabio; Smits, Theo H M; Duffy, Brion

    2011-06-01

    The clustered regularly interspaced short palindromic repeat (CRISPR)/Cas system confers acquired heritable immunity against mobile nucleic acid elements in prokaryotes, limiting phage infection and horizontal gene transfer of plasmids. In CRISPR arrays, characteristic repeats are interspersed with similarly sized nonrepetitive spacers derived from transmissible genetic elements and acquired when the cell is challenged with foreign DNA. New spacers are added sequentially and the number and type of CRISPR units can differ among strains, providing a record of phage/plasmid exposure within a species and giving a valuable typing tool. The aim of this work was to investigate CRISPR diversity in the highly homogeneous species Erwinia amylovora, the causal agent of fire blight. A total of 18 CRISPR genotypes were defined within a collection of 37 cosmopolitan strains. Strains from Spiraeoideae plants clustered in three major groups: groups II and III were composed exclusively of bacteria originating from the United States, whereas group I generally contained strains of more recent dissemination obtained in Europe, New Zealand, and the Middle East. Strains from Rosoideae and Indian hawthorn (Rhaphiolepis indica) clustered separately and displayed a higher intrinsic diversity than that of isolates from Spiraeoideae plants. Reciprocal exclusion was generally observed between plasmid content and cognate spacer sequences, supporting the role of the CRISPR/Cas system in protecting against foreign DNA elements. However, in several group III strains, retention of plasmid pEU30 is inconsistent with a functional CRISPR/Cas system.

  19. Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemsitry in the region of Thulium, Lutetium, and Tantalum I. Results of Built in Spherical Symmetry in a Deformed Region

    SciTech Connect

    Hoffman, R. D.

    2013-09-06

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from Terbium (Z = 65) to Rhenium (Z = 75). Of particular interest are the cross sections on Tm, Lu, and Ta including reactions on isomeric targets.

  20. APG350 induces superior clustering of TRAIL receptors and shows therapeutic antitumor efficacy independent of cross-linking via Fcγ receptors.

    PubMed

    Gieffers, Christian; Kluge, Michael; Merz, Christian; Sykora, Jaromir; Thiemann, Meinolf; Schaal, René; Fischer, Carmen; Branschädel, Marcus; Abhari, Behnaz Ahangarian; Hohenberger, Peter; Fulda, Simone; Fricke, Harald; Hill, Oliver

    2013-12-01

    Cancer cells can be specifically driven into apoptosis by activating Death-receptor-4 (DR4; TRAIL-R1) and/or Death-receptor-5 (DR5; TRAIL-R2). Albeit showing promising preclinical efficacy, first-generation protein therapeutics addressing this pathway, especially agonistic anti-DR4/DR5-monoclonal antibodies, have not been clinically successful to date. Due to their bivalent binding mode, effective apoptosis induction by agonistic TRAIL-R antibodies is achieved only upon additional events leading to antibody-multimer formation. The binding of these multimers to their target subsequently leads to effective receptor-clustering on cancer cells. The research results presented here report on a new class of TRAIL-receptor agonists overcoming this intrinsic limitation observed for antibodies in general. The main feature of these agonists is a TRAIL-mimic consisting of three TRAIL-protomer subsequences combined in one polypeptide chain, termed the single-chain TRAIL-receptor-binding domain (scTRAIL-RBD). In the active compounds, two scTRAIL-RBDs with three receptor binding sites each are brought molecularly in close proximity resulting in a fusion protein with a hexavalent binding mode. In the case of APG350-the prototype of this engineering concept-this is achieved by fusing the Fc-part of a human immunoglobulin G1 (IgG1)-mutein C-terminally to the scTRAIL-RBD polypeptide, thereby creating six receptor binding sites per drug molecule. In vitro, APG350 is a potent inducer of apoptosis on human tumor cell lines and primary tumor cells. In vivo, treatment of mice bearing Colo205-xenograft tumors with APG350 showed a dose-dependent antitumor efficacy. By dedicated muteins, we confirmed that the observed in vivo efficacy of the hexavalent scTRAIL-RBD fusion proteins is-in contrast to agonistic antibodies-independent of FcγR-based cross-linking events.

  1. Covert checks by standardised patients of general practitioners' delivery of new periodic health examinations: clustered cross-sectional study from a consumer organisation

    PubMed Central

    Thaler, Kylie; Harris, Mark F

    2012-01-01

    Objective To assess if data collected by a consumer organisation are valid for a health service research study on physicians' performance in preventive care. To report first results of the analysis of physicians performance like consultation time and guideline adherence in history taking. Design Secondary data analysis of a clustered cross-sectional direct observation survey. Setting General practitioners (GPs) in Vienna, Austria, visited unannounced by mystery shoppers (incognito standardised patients (ISPs)). Participants 21 randomly selected GPs were visited by two different ISPs each. 40 observation protocols were realised. Main outcome measures Robustness of sampling and data collection by the consumer organisation. GPs consultation and waiting times, guideline adherence in history taking. Results The double stratified random sampling method was robust and representative for the private and contracted GPs mix of Vienna. The clinical scenarios presented by the ISPs were valid and believable, and no GP realised the ISPs were not genuine patients. The average consultation time was 46 min (95% CI 37 to 54 min). Waiting times differed more than consultation times between private and contracted GPs. No differences between private and contracted GPs in terms of adherence to the evidence-based guidelines regarding history taking including questions regarding alcohol use were found. According to the analysis, 20% of the GPs took a perfect history (95% CI 9% to 39%). Conclusions The analysis of secondary data collected by a consumer organisation was a valid method for drawing conclusions about GPs preventive practice. Initial results, like consultation times longer than anticipated, and the moderate quality of history taking encourage continuing the analysis on available clinical data. PMID:22872721

  2. Prediction of the fate of Hg and other contaminants in soil around a former chlor-alkali plant using Fuzzy Hierarchical Cross-Clustering approach.

    PubMed

    Frenţiu, Tiberiu; Ponta, Michaela; Sârbu, Costel

    2015-11-01

    An associative simultaneous fuzzy divisive hierarchical algorithm was used to predict the fate of Hg and other contaminants in soil around a former chlor-alkali plant. The algorithm was applied on several natural and anthropogenic characteristics of soil including water leachable, mobile, semi-mobile, non-mobile fractions and total Hg, Al, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Sr, Zn, water leachable fraction of Cl(-), NO3(-) and SO4(2)(-), pH and total organic carbon. The cross-classification algorithm provided a divisive fuzzy partition of the soil samples and associated characteristics. Soils outside the perimeter of the former chlor-alkali plant were clustered based on the natural characteristics and total Hg. In contaminated zones Hg speciation becomes relevant and the assessment of species distribution is necessary. The descending order of concentration of Hg species in the test site was semi-mobile>mobile>non-mobile>water-leachable. Physico-chemical features responsible for similarities or differences between uncontaminated soil samples or contaminated with Hg, Cu, Zn, Ba and NO3(-) were also highlighted. Other characteristics of the contaminated soil were found to be Ca, sulfate, Na and chloride, some of which with influence on Hg fate. The presence of Ca and sulfate in soil induced a higher water leachability of Hg, while Cu had an opposite effect by forming amalgam. The used algorithm provided an in-deep understanding of processes involving Hg species and allowed to make prediction of the fate of Hg and contaminants linked to chlor-alkali-industry.

  3. Cluster Multipoint Observations of the Spatial Structure and Time Development of Auroral Acceleration Region Field-aligned Current Systems, Potentials, and Plasma

    NASA Astrophysics Data System (ADS)

    Hull, A. J.; Chaston, C. C.; Fillingim, M. O.; Frey, H. U.; Bonnell, J. W.; Mozer, F.; Goldstein, M. L.

    2014-12-01

    The auroral acceleration region is an integral part of the magnetosphere-ionosphere electrodynamic system, and plays a key role in the transport of plasma and energy between Earth and space. This region is embedded with field-aligned currents that couple the magnetosphere to the ionosphere and is where parallel electric fields form that accelerate plasma to and from these regions. Though considerable progress has been made, the complex interplay between field-aligned current system formation, the development of parallel electric fields, changes in the plasma constituents, and auroral emissions consequences are not fully understood. The Cluster mission is well suited for studying the structure and dynamics of the auroral acceleration region. Over its lifetime, Cluster has sampled much of this region with closely spaced probes enabling the distinction between temporal effects from spatial variations. Moreover, this data when combined with auroral images from IMAGE or THEMIS GBO-ASI enable an assessment of the auroral emission response to spatial morphology and temporal development of structures seeded in the auroral acceleration region. In this study we present a survey of Cluster multi-point traversals within and just above the auroral acceleration region (≤ 3 Re altitude). In particular we highlight the spatial morphology and developmental sequence of auroral acceleration current systems, potentials and plasma constituents, with the aim of identifying controlling factors, and assessing ionospheric consequences under different conditions. Our results suggest that the "Alfvénic" activity may be an important precursor and perhaps may be playing an essential role in the development of "quasi-static" current systems during quiet and substorm active times. Such events are generally the result of an injection mediated process at or near the plasma sheet boundary layer, resulting in the local expansion of the plasma sheet. Key features of the conversion from Alfv

  4. Prevalence and Risk Factors of Lassa Seropositivity in Inhabitants of the Forest Region of Guinea: A Cross-Sectional Study

    PubMed Central

    Kernéis, Solen; Koivogui, Lamine; Magassouba, N'Faly; Koulemou, Kekoura; Lewis, Rosamund; Aplogan, Aristide; Grais, Rebecca F.; Guerin, Philippe J.; Fichet-Calvet, Elisabeth

    2009-01-01

    Background Lassa fever is a viral hemorrhagic fever endemic in West Africa. The reservoir host of the virus is a multimammate rat, Mastomys natalensis. Prevalence estimates of Lassa virus antibodies in humans vary greatly between studies, and the main modes of transmission of the virus from rodents to humans remain unclear. We aimed to (i) estimate the prevalence of Lassa virus–specific IgG antibodies (LV IgG) in the human population of a rural area of Guinea, and (ii) identify risk factors for positive LV IgG. Methods and Findings A population-based cross-sectional study design was used. In April 2000, all individuals one year of age and older living in three prefectures located in the tropical secondary forest area of Guinea (Gueckedou, Lola and Yomou) were sampled using two-stage cluster sampling. For each individual identified by the sampling procedure and who agreed to participate, a standardized questionnaire was completed to collect data on personal exposure to potential risk factors for Lassa fever (mainly contact with rodents), and a blood sample was tested for LV IgG. A multiple logistic regression model was used to determine risk factors for positive LV IgG. A total of 1424 subjects were interviewed and 977 sera were tested. Prevalence of positive LV Ig was of 12.9% [10.8%–15.0%] and 10.0% [8.1%–11.9%] in rural and urban areas, respectively. Two risk factors of positive LV IgG were identified: to have, in the past twelve months, undergone an injection (odds ratio [OR] = 1.8 [1.1–3.1]), or lived with someone displaying a haemorrhage (OR = 1.7 [1.1–2.9]). No factors related to contacts with rats and/or mice remained statistically significant in the multivariate analysis. Conclusions Our study underlines the potential importance of person-to-person transmission of Lassa fever, via close contact in the same household or nosocomial exposure. PMID:19924222

  5. Joint Inversion of Seismic and Magnetotelluric Data in the Parkfield Region of California Using the Normalized Cross-Gradient Constraint

    NASA Astrophysics Data System (ADS)

    Bennington, Ninfa L.; Zhang, Haijiang; Thurber, Clifford H.; Bedrosian, Paul A.

    2015-05-01

    We present jointly inverted models of P-wave velocity (Vp) and electrical resistivity for a two-dimensional profile centered on the San Andreas Fault Observatory at Depth (SAFOD). Significant structural similarity between main features of the separately inverted Vp and resistivity models is exploited by carrying out a joint inversion of the two datasets using the normalized cross-gradient constraint. This constraint favors structurally similar Vp and resistivity images that adequately fit the seismic and magnetotelluric (MT) datasets. The new inversion code, tomoDDMT, merges the seismic inversion code tomoDD and the forward modeling and sensitivity kernel subroutines of the MT inversion code OCCAM2DMT. TomoDDMT is tested on a synthetic dataset and demonstrates the code's ability to more accurately resolve features of the input synthetic structure relative to the separately inverted resistivity and velocity models. Using tomoDDMT, we are able to resolve a number of key issues raised during drilling at SAFOD. We are able to infer the distribution of several geologic units including the Salinian granitoids, the Great Valley sequence, and the Franciscan Formation. The distribution and transport of fluids at both shallow and great depths is also examined. Low values of velocity/resistivity attributed to a feature known as the Eastern Conductor (EC) can be explained in two ways: the EC is a brine-filled, high porosity region, or this region is composed largely of clay-rich shales of the Franciscan. The Eastern Wall, which lies immediately adjacent to the EC, is unlikely to be a fluid pathway into the San Andreas Fault's seismogenic zone due to its observed higher resistivity and velocity values.

  6. HIV testing in re-education through labour camps in Guangxi Autonomous Region, China (a cross-sectional survey)

    PubMed Central

    Yap, Lorraine; Reekie, Joanne; Liu, Wei; Chen, Yi; Wu, Zunyou; Li, Jianghong; Zhang, Lei; Wand, Handan; Donovan, Basil; Butler, Tony

    2015-01-01

    Objective HIV testing is mandatory in re-education-through-labour camps (laojiaosuo) in China yet no studies have reported on the process. Methods The survey response rate was 100% although 29 detainees were excluded because they were under 18 years of age. A cross-sectional face-to-face survey was conducted in three labour camps in Guangxi, located in the south-western region of China. Results Of the 755 detainees surveyed, 725 (96%) reported having a blood test in the labour camps of whom 493 (68%) thought this included an HIV test. 61 detainees self-reported they were HIV infected, their status confirmed by medical records, if available. Of these, 53 (87%) recalled receiving post-test HIV education, and 15 (25%) were currently receiving HIV antiretroviral therapy. Pretest education on HIV was provided to 233/725 (32%) detainees. The study further reports on detainees’ reactions and feelings towards non-disclosure and disclosure of their HIV test results in the labour camps. Conclusions Mandatory testing is almost universal in the labour camps although a proportion of detainees were unaware that this included an HIV test. HIV test results should be disclosed to all labour camp detainees to reduce their distress of not knowing and prevent misconceptions about their HIV status. Labour camps provide another opportunity to implement universal treatment (‘Test and Treat’) to prevent the spread of HIV. PMID:25739879

  7. Contributions of long-range and regional atmospheric transport on pesticide concentrations along a transect crossing a mountain divide.

    PubMed

    Lavin, Karen S; Hageman, Kimberly J

    2013-02-05

    Twenty-one halogenated legacy and current-use pesticides and pesticide degradation products were measured in pine needles along a coast-to-coast transect that crossed the Southern Alps of New Zealand. Concentration profiles of nine pesticides were used to determine the influence of geographic sources on the atmospheric pesticide burden at the mountain sites. Pesticide concentration profiles were calculated for each source and mountain site by normalizing concentrations (adjusted for temperature at the site and air-needle partitioning) to the sum of all pesticide concentrations at the site. Each mountain site profile was compared to varying mixtures of the potential source profiles to determine the percent contribution of each source. The highest elevation mountain sites were primarily influenced by long-range, synoptic-scale northwesterly winds. Westerly upslope winds had little influence on any of the mountain sites. Easterly upslope winds from the Canterbury Plains, an agricultural region, strongly influenced the mountain sites within close proximity and had progressively less influence with distance.

  8. Cross-Characterization of Aerosol Properties from Multiple Spaceborne Sensors Facilitated by Regional Ground-Based Observations

    NASA Technical Reports Server (NTRS)

    Petrenko, Maksym; Ichoku, Charles; Leptoukh, Gregory

    2010-01-01

    Aerosol observations from space have become a standard source for retrieval of aerosol properties on both regional and global scales. Indeed, the large number of currently operational spaceborne sensors provides for unprecedented access to the most complete set of complimentary aerosol measurements ever to be available. Nonetheless, this resource remains under-utilized, largely due to the discrepancies and differences existing between the sensors and their aerosol products. To characterize the inconsistencies and bridge the gap that exists between the sensors, we have designed and implemented an online Multi-sensor Aerosol Products Sampling System (MAPSS) that facilitates the joint sampling of aerosol data from multiple sensors. MAPSS consistently samples aerosol products from multiple spaceborne sensors using a unified spatial and temporal resolution, where each dataset is sampled over Aerosol Robotic Network (AERONET) locations together with coincident AERONET data samples. In this way, MAPSS enables a direct cross-characterization and data integration between aerosol products from multiple sensors. Moreover, the well-characterized co-located ground-based AERONET data provides the basis for the integrated validation of these products.

  9. Photoionization of molecular clusters

    NASA Astrophysics Data System (ADS)

    Andres, R. P.; Calo, J. M.

    1981-12-01

    An experimental apparatus consisting of a novel multiple expansion cluster source coupled with a molecular beam system and photoionization mass spectrometer has been designed and constructed. This apparatus has been thoroughly tested and preliminary measurements of the growth kinetics of water clusters and the photoionization cross section of the water dimer have been carried out.

  10. The Caulobacter crescentus flaFG region regulates synthesis and assembly of flagellin proteins encoded by two genetically unlinked gene clusters.

    PubMed Central

    Schoenlein, P V; Lui, J; Gallman, L; Ely, B

    1992-01-01

    At a specific time in the Caulobacter crescentus cell cycle, a single flagellar filament and multiple receptor sites for the swarmer-specific phage phi Cbk are assembled at one pole of the predivisional cell. One cluster of genes required for this morphogenesis, the flaYG region, includes the flgJKL genes, which encode structural proteins of the flagellar filament. These flagellin genes are flanked by genes required for filament assembly, the flaYE genes at one end and the flaF-flbT-flbA-flaG genes at the other. In this study, we characterized mutants carrying large chromosomal deletions within this region. Several of these strains are phi CbK resistant and produce a novel 22-kDa flagellin that is not assembled into flagella. Merodiploid strains containing either the entire flaFG region or individual fla transcription units from this region were constructed. These strains were used to correlate the presence or absence of specific gene products to changes in flagellin synthesis, filament assembly, or phage sensitivity. As a result of these studies, we were able to conclude that (i) the production of the 22-kDa flagellin results from the absence of the flbA and flaG gene products, which appear to be components of a flagellin-processing pathway common to the 25-, 27-, and 29-kDa flagellins; (ii) flbT negatively modulates the synthesis of the 27- and 25-kDa flagellins from two genetically unlinked gene clusters; (iii) flgL is the only flagellin gene able to encode the 27-kDa flagellin, and this flagellin appears to be required for the efficient assembly of the 25-kDa flagellins; (iv) flaF is required for filament assembly; and (v) phi CbK resistance results from the deletion of at least two genes in the flaFG region. Images PMID:1400155

  11. Cloud Structure of Galactic OB Cluster-forming Regions from Combining Ground- and Space-based Bolometric Observations

    NASA Astrophysics Data System (ADS)

    Lin, Yuxin; Liu, Hauyu Baobab; Li, Di; Zhang, Zhi-Yu; Ginsburg, Adam; Pineda, Jaime E.; Qian, Lei; Galván-Madrid, Roberto; McLeod, Anna Faye; Rosolowsky, Erik; Dale, James E.; Immer, Katharina; Koch, Eric; Longmore, Steve; Walker, Daniel; Testi, Leonardo

    2016-09-01

    We have developed an iterative procedure to systematically combine the millimeter and submillimeter images of OB cluster-forming molecular clouds, which were taken by ground-based (CSO, JCMT, APEX, and IRAM-30 m) and space telescopes (Herschel and Planck). For the seven luminous (L\\gt {10}6 L ⊙) Galactic OB cluster-forming molecular clouds selected for our analyses, namely W49A, W43-Main, W43-South, W33, G10.6-0.4, G10.2-0.3, and G10.3-0.1, we have performed single-component, modified blackbody fits to each pixel of the combined (sub)millimeter images, and the Herschel PACS and SPIRE images at shorter wavelengths. The ˜10″ resolution dust column density and temperature maps of these sources revealed dramatically different morphologies, indicating very different modes of OB cluster-formation, or parent molecular cloud structures in different evolutionary stages. The molecular clouds W49A, W33, and G10.6-0.4 show centrally concentrated massive molecular clumps that are connected with approximately radially orientated molecular gas filaments. The W43-Main and W43-South molecular cloud complexes, which are located at the intersection of the Galactic near 3 kpc (or Scutum) arm and the Galactic bar, show a widely scattered distribution of dense molecular clumps/cores over the observed ˜10 pc spatial scale. The relatively evolved sources G10.2-0.3 and G10.3-0.1 appear to be affected by stellar feedback, and show a complicated cloud morphology embedded with abundant dense molecular clumps/cores. We find that with the high angular resolution we achieved, our visual classification of cloud morphology can be linked to the systematically derived statistical quantities (i.e., the enclosed mass profile, the column density probability distribution function (N-PDF), the two-point correlation function of column density, and the probability distribution function of clump/core separations). In particular, the massive molecular gas clumps located at the center of G10.6-0.4 and

  12. Prevalence and predictors of exclusive breastfeeding among women in Kilimanjaro region, Northern Tanzania: a population based cross-sectional study

    PubMed Central

    2013-01-01

    Background Exclusive breastfeeding (EBF) is a simple and cost-effective intervention to improve child health and survival. Effective EBF has been estimated to avert 13% - 15% of under-five mortality and contribute to reduce mother to child transmission of HIV. The prevalence of EBF for infant less than six months is low in most developing countries, including Tanzania (50%). While the Tanzania Demographic Health Survey collects information on overall EBF prevalence, it does not evaluate factors influencing EBF. The aim of this paper was to determine the prevalence and predictors of exclusive breastfeeding in urban and rural areas in Kilimanjaro region. Methods A population-based cross-sectional study was conducted between June 2010 to March 2011 among women with infants aged 6–12 months in Kilimanjaro. Multi-stage proportionate to size sampling was used to select participants from all the seven districts of the region. A standardized questionnaire was used to collect socio-demographic, reproductive, alcohol intake, breastfeeding patterns and nutritional data during the interviews. Estimation on EBF was based on recall since birth. Multivariable logistic regression was used to obtain independent predictors of EBF. Results A total of 624 women participated, 77% (483) from rural areas. The prevalence of EBF up to six months in Kilimanjaro region was 20.7%, without significant differences in the prevalence of EBF up to six months between urban (22.7%) and rural areas (20.1%); (OR = 0.7, 95% CI 0.5,1.4). In multivariable analysis, advice on breastfeeding after delivery (Adjusted odds ratio, AOR = 2.6, 95% CI 1.5, 4.6) was positively associated with EBF up to six months. Compared to married/cohabiting and those who do not take alcohol, single mothers (AOR = 0.4, 95% CI 0.2, 0.9) and mothers who drank alcohol (AOR = 0.4, 95% CI 0.3, 0.7) had less odds to practice EBF up to six months. Conclusion Prevalence of EBF up to six months is still low in

  13. Regional Technology Assets and Opportunities: The Geographic Clustering of High-Tech Industry, Science and Innovation in Appalachia.

    ERIC Educational Resources Information Center

    Feser, Edward; Goldstein, Harvey; Renski, Henry; Renault, Catherine

    A study identified 100 sub-regional concentrations of technology-related employment, research and development, and applied innovation within and immediately adjacent to the 406-county service area of the Appalachian Regional Commission (ARC). Among the findings are that Appalachia's technology sector is comparatively small but expanding, with most…

  14. Neutralizing linear epitopes of B19 parvovirus cluster in the VP1 unique and VP1-VP2 junction regions.

    PubMed Central

    Saikawa, T; Anderson, S; Momoeda, M; Kajigaya, S; Young, N S

    1993-01-01

    Presentation of linear epitopes of the B19 parvovirus capsid proteins as peptides might be a useful vaccine strategy. We produced overlapping fusion proteins to span the viral capsid sequence, inoculated rabbits, and determined whether the resulting antisera contained antibodies that neutralized the ability of the virus to infect human erythroid progenitor cells. Antibodies that bound to virus in an enzyme-linked immunosorbent assay were present in antisera raised against 10 of 11 peptides; strongest activity was found for antisera against the carboxyl-terminal half of the major capsid protein. However, strong neutralizing activity was elicited in animals immunized with peptides from the amino-terminal portion of the unique region of the minor capsid protein and peptides containing the sequence of the junction region between the minor and major capsid proteins. The development of neutralizing activity in animals was elicited most rapidly with the fusion peptide from the first quarter of the unique region. A 20-amino-acid region of the unique region of the minor capsid protein was shown to contain a neutralizing epitope. Multiple antigenic peptides, based on the sequence of the unique region and produced by covalent linkage through a polylysine backbone, elicited strong neutralizing antibody responses. Synthetic peptides and fusion proteins containing small regions of the unique portion of the minor capsid protein might be useful as immunogens in a human vaccine against B19 parvovirus. Images PMID:7684458

  15. Factors associated with dog rabies vaccination in Bhol, Philippines: results of a cross-sectional cluster survey conducted following the island-wide rabies elimination campaign.

    PubMed

    Davlin, S; Lapiz, S M; Miranda, M E; Murray, K

    2013-11-01

    The Philippines has a long history of rabies control efforts in their dog populations; however, long-term success of such programmes and the goal of rabies elimination have not yet been realized. The Bohol Rabies Prevention and Elimination Program was developed as an innovative approach to canine rabies control in 2007. The objective of this study was to assess canine rabies vaccination coverage in the owned-dog population in Bohol and to describe factors associated with rabies vaccination 2 years after implementation of the programme. We utilized a cross-sectional cluster survey based on the World Health Organization's Expanded Programme on Immunization coverage survey technique. We sampled 460 households and collected data on 539 dogs residing within these households. Seventy-seven per cent of surveyed households reported owning at least one dog. The human-to-dog ratio was approximately 4 : 1, and the mean number of dogs owned per household was 1.6. Based on this ratio, we calculated an owned-dog population of almost 300 000. Overall, 71% of dogs were reported as having been vaccinated for rabies at some time in their lives; however, only 64% of dogs were reported as having been recently vaccinated. Dogs in our study were young (median age = 24 months). The odds of vaccination increased with increasing age. Dogs aged 12-23 months had 4.6 times the odds of vaccination compared to dogs aged 3-11 months (95% CI 1.8-12.0; P = 0.002). Confinement of the dog both day and night was also associated with increased odds of vaccination (OR = 2.1; 95% CI 0.9-4.9; P = 0.07), and this result approached statistical significance. While the programme is on track to meet its goal of 80% vaccination coverage, educational efforts should focus on the need to confine dogs and vaccinate young dogs.

  16. Transcriptional and bioinformatic analysis of the 56.8 kb DNA region amplified in tandem repeats containing the penicillin gene cluster in Penicillium chrysogenum.

    PubMed

    Fierro, Francisco; García-Estrada, Carlos; Castillo, Nancy I; Rodríguez, Raquel; Velasco-Conde, Tania; Martín, Juan-Francisco

    2006-09-01

    High penicillin-producing strains of Penicillium chrysogenum contain 6-14 copies of the three clustered structural biosynthetic genes, pcbAB, pcbC, and penDE [Barredo, J.L., Díez, B., Alvarez, E., Martín, J.F., 1989. Large amplification of a 35-kb DNA fragment carrying two penicillin biosynthetic genes in high penicillin producing strains of Penicillium chrysogenum. Curr. Genet. 16, 453-459; Smith, D.J., Bull, J.H., Edwards, J., Turner, G., 1989. Amplification of the isopenicillin N synthetase gene in a strain of Penicillium chrysogenum producing high levels of penicillin. Mol. Gen. Genet. 216, 492-497.] . The cluster is located in a 56.8 kb DNA region bounded by a conserved TGTAAA/T hexanucleotide that undergoes amplification in tandem repeats [Fierro, F., Barredo, J.L., Díez, B., Gutiérrez, S., Fernández, F.J., Martín, J.F., 1995. The penicillin gene cluster is amplified in tandem repeats linked by conserved hexanucleotide sequences. Proc. Natl. Acad. Sci. USA 92, 6200-6204; Newbert, R.W., Barton, B., Greaves, P., Harper, J., Turner, G., 1997. Analysis of a commercially improved Penicillium chrysogenum strain series: involvement of recombinogenic regions in amplification and deletion of the penicillin biosynthesis gene cluster. J. Ind. Microbiol. Biotechnol. 19, 18-27]. Transcriptional analysis of this amplified region (AR) revealed the presence of at least eight transcripts expressed in penicillin producing conditions. Three of them correspond to the known penicillin biosynthetic genes, pcbAB, pcbC, and penDE. To locate genes related to penicillin precursor formation, or penicillin transport and regulation we have sequenced and analyzed the 56.8 kb amplified region of P. chrysogenum AS-P-78, finding a total of 16 open reading frames. Two of these ORFs have orthologues of known function in the databases. Other ORFs showed similarities to specific domains occurring in different proteins and superfamilies which allowed to infer their probable function. ORF11

  17. Cardiovascular health among healthy population of Northeast region of India: a cross-sectional study comparing urban-tribal difference.

    PubMed

    Saha, Soma; Gupta, Kinnari; Kumar, Soumitra

    2013-12-01

    Cardiovascular disease is the leading cause of adult mortality in India but data on the prevalence of cardiovascular risk factors are scarce, especially from North-east region of India. This study aims to assess the prevalence and the urban/tribal gradient of cardiovascular disease risk factors among healthy population of Tripura. A cross-sectional study was carried out among 238 healthy individuals (140 urban and 98 tribal) in one urban and five tribal areas of Tripura. Data was collected on sociodemographic profile, medical history, anthropometry, dietary patterns and addiction. Fasting blood samples were collected for biochemical analysis. Prevalence of cardiovascular disease risk factors and short-term cardiovascular disease risk score was calculated. The association of independent variables with 10-year cardiovascular disease risk score were examined by using multiple regression model. Prevalence of obesity, hypertension, diabetes, dyslipidaemia, metabolic syndrome and short-term cardiovascular disease risk score were higher in urban group. Urban people had higher salt, calories and fat intake. No difference was found in the addiction patterns of tobacco and alcohol but frequency and quantity being higher in tribal area. Dyslipidaemia and alcohol consumption showed significant positive association with 10-year cardiovascular disease risk score in both groups. While the non-sedentary lifestyle and dietary habits (low salt, low fat, carbohydrate predominant) of tribal population need to be promoted as a whole across the nation, they need to be protected from the adverse effects of rampant prevalence of tobacco and alcohol addiction among them. Urban population need to be extricated from adverse effects of sedentary lifestyle, modern food habits (high salt, high fat) and tobacco-alcohol addiction.

  18. Quality of work life among primary health care nurses in the Jazan region, Saudi Arabia: a cross-sectional study

    PubMed Central

    2012-01-01

    Background Quality of work life (QWL) is defined as the extent to which an employee is satisfied with personal and working needs through participating in the workplace while achieving the goals of the organization. QWL has been found to influence the commitment and productivity of employees in health care organizations, as well as in other industries. However, reliable information on the QWL of primary health care (PHC) nurses is limited. The purpose of this study was to assess the QWL among PHC nurses in the Jazan region, Saudi Arabia. Methods A descriptive research design, namely a cross-sectional survey, was used in this study. Data were collected using Brooks’ survey of quality of nursing work life and demographic questions. A convenience sample was recruited from 134 PHC centres in Jazan, Saudi Arabia. The Jazan region is located in the southern part of Saudi Arabia. A response rate of 91% (n = 532/585) was achieved (effective response rate = 87%, n = 508). Data analysis consisted of descriptive statistics, t-test and one way-analysis of variance. Total scores and subscores for QWL items and item summary statistics were computed and reported using SPSS version 17 for Windows. Results Findings suggested that the respondents were dissatisfied with their work life. The major influencing factors were unsuitable working hours, lack of facilities for nurses, inability to balance work with family needs, inadequacy of vacations time for nurses and their families, poor staffing, management and supervision practices, lack of professional development opportunities, and an inappropriate working environment in terms of the level of security, patient care supplies and equipment, and recreation facilities (break-area). Other essential factors include the community’s view of nursing and an inadequate salary. More positively, the majority of nurses were satisfied with their co-workers, satisfied to be nurses and had a sense of belonging in their workplaces

  19. Cluster and field elliptical galaxies at z 1.3. The marginal role of the environment and the relevance of the galaxy central regions

    NASA Astrophysics Data System (ADS)

    Saracco, P.; Gargiulo, A.; Ciocca, F.; Marchesini, D.

    2017-01-01

    . Also the Σ1 kpc-mass relation follows two different regimes, above and below the transition mass (Σ1 kpc ∝ Μ*1.07mt) defining a transition mass density Σ1 kpc ≃ 2-3 × 103M⊙ pc-2. The effective stellar mass density ΣRe does not correlate with mass; dense/compact galaxies can be assembled over a wide mass regime, independently of the environment. The central stellar mass density, Σ1 kpc, besides being correlated with the mass, is correlated to the age of the stellar population: the higher the central stellar mass density, the higher the mass, the older the age of the stellar population. Conclusions: While we found some evidence of environmental effects on the elliptical galaxies as a population, we did not find differences between the intrinsic properties of cluster and field elliptical galaxies at comparable redshift. The structure and the shaping of elliptical galaxies at z 1.3 do not depend on the environment. However, a dense environment seems to be more efficient in assembling high-mass large ellipticals, much rarer in the field at this redshift. The correlation found between the central stellar mass density and the age of the galaxies beside the mass shows the close connection of the central regions to the main phases of mass growth.

  20. Clustering of geriatric deficits emerges to be an essential feature of ageing - results of a cross-sectional study in Poland

    PubMed Central

    Karolina, Piotrowicz; Agnieszka, Pac; Barbara, Skalska Anna; Jerzy, Chudek; Alicja, Klich-Rączka; Aleksandra, Szybalska; Jean-Pierre, Michel; Tomasz, Grodzicki

    2016-01-01

    The majority of old people suffer from various clinical conditions that affect health, functioning and quality of life. This research is a part of a cross-sectional, nationwide PolSenior Study that provides a comprehensive assessment of eight geriatric impairments and their co-occurrence in a representative sample (3471 participant aged 65-104 years, mean age 78.3 years) of the old adults living in the community in Poland. The participants were recruited randomly from all administrative regions of Poland by a three-stage, proportional, stratified-by-age group selection process. Eight geriatric conditions were assessed: falls, incontinences, cognitive impairment, mood disorders, vision and hearing impairments, malnutrition, and functional dependence. We showed that the most common deficits causing disability were vision and hearing impairments, and mood disorders, with more than two thirds of the participants presented at least one geriatric deficit. We showed that presence any of the analyzed conditions significantly increased the risk for co-occurrence of other examined weaknesses. The highest prevalence odds ratios were for functional dependence and, respectively: malnutrition (8.61, 95%CI: 4.70-15.80), incontinences (8.0, 95%CI:5.93-10.70), and cognitive impairment (7.22; 95%CI:5.91-8.83). We concluded that the majority of the old people living in the community present various clinical conditions that prompt disability. PMID:27794563

  1. Neutron total and scattering cross sections of /sup 6/Li in the few MeV region

    SciTech Connect

    Smith, A.; Guenther, P.; Whalen, J.

    1980-02-01

    Neutron total cross sections of /sup 6/Li are measured from approx. 0.5 to approx. 4.8 MeV at intervals of approx.< 10 keV. Neutron differential elastic-scattering cross sections are measured from 1.5 to 4.0 MeV at approx.> 10 scattering angles and at incident-neutron intervals of approx.< 100 keV. Neutron differential inelastic-scattering cross sections are measured in the incident-energy range 3.5 to 4.0 MeV. The experimental results are extended to lower energies using measured neutron total cross sections recently reported elsewhere by the authors. The composite experimental data (total cross sections from 0.1 to 4.8 MeV and scattering cross sections from 0.22 to 4.0 MeV) are interpreted in terms of a simple two-level R-matrix model which describes the observed cross sections and implies the reaction cross section in unobserved channels; notably the (n;..cap alpha..)t reaction (Q = 4.783 MeV). The experimental and calculational results are compared with previously reported results as summarized in the ENDF/B-V evaluated nuclear data file.

  2. Determination of (n,{gamma}) cross sections in the rare-earth region using the surrogate ratio method

    SciTech Connect

    Goldblum, B. L.; Prussin, S. G.; Agvaanluvsan, U.; Bernstein, L. A.; Bleuel, D. L.; Younes, W.; Guttormsen, M.

    2008-12-15

    The surrogate ratio method was used to convert experimentally determined relative {gamma}-decay probabilities for excited {sup 171}Yb and {sup 161}Dy nuclei, populated using ({sup 3}He, {sup 3}He{sup '}) and ({sup 3}He, {alpha}) reactions, into neutron-induced {gamma}-decay cross sections in an equivalent neutron energy range of 165-465 keV. The relative {gamma}-decay probabilities were measured using the CACTUS array at the Oslo Cyclotron Laboratory and were found to agree with the ratio of neutron-induced {gamma}-decay cross sections for the same compound nuclei over the range of excitation energies measured. No significant entrance-channel effects on the extracted (n,{gamma}) cross sections were observed. The cross sections obtained using the surrogate ratio method were compared to directly measured neutron-capture cross sections and found to agree within the total estimated uncertainty over the range of equivalent neutron energies measured.

  3. Gbeta subunit interacts with a peptide encoding region 956-982 of adenylyl cyclase 2. Cross-linking of the peptide to free Gbetagamma but not the heterotrimer.

    PubMed

    Weng, G; Li, J; Dingus, J; Hildebrandt, J D; Weinstein, H; Iyengar, R

    1996-10-25

    The region encoded by amino acids 956-982 of adenylyl cyclase 2 is important for Gbetagamma stimulation. Interactions of a peptide encoding the 956-982 region of adenylyl cyclase 2 (QEHAQEPERQYMHIGTMVEFAYALVGK (QEHA peptide)) with Gbetagamma subunits were studied. QEHA peptide was covalently attached to beta subunit of free Gbetagamma by the cross-linker N-succinimidyl(4-iodoacetyl)aminobenzoate. Cross-linking was proportional to the amount of QEHA peptide added; other control peptides cross-linked minimally. When Go was used, very little cross-linking was observed with GDP and EDTA, but upon activation by guanosine 5'-3-O-(thio)triphosphate and Mg2+, specific cross-linking of the QEHA peptide to Gbeta was observed. We conclude that beta subunits of G proteins contain effector interaction domains that are occluded by Galpha subunits in the heterotrimer. Molecular modeling studies used to dock the QEHA peptide on to Gbeta indicate that amino acids 75-165 of Gbeta may be involved in effector interactions.

  4. Cluster Headache

    MedlinePlus

    Cluster headache Overview By Mayo Clinic Staff Cluster headaches, which occur in cyclical patterns or clusters, are one of the most painful types of headache. A cluster headache commonly awakens you ...

  5. Double differential cross sections for proton induced electron emission from molecular analogues of DNA constituents for energies in the Bragg peak region

    NASA Astrophysics Data System (ADS)

    Rudek, Benedikt; Bennett, Daniel; Bug, Marion U.; Wang, Mingjie; Baek, Woon Yong; Buhr, Ticia; Hilgers, Gerhard; Champion, Christophe; Rabus, Hans

    2016-09-01

    For track structure simulations in the Bragg peak region, measured electron emission cross sections of DNA constituents are required as input for developing parameterized model functions representing the scattering probabilities. In the present work, double differential cross sections were measured for the electron emission from vapor-phase pyrimidine, tetrahydrofuran, and trimethyl phosphate that are structural analogues to the base, the sugar, and the phosphate residue of the DNA, respectively. The range of proton energies was from 75 keV to 135 keV, the angles ranged from 15° to 135°, and the electron energies were measured from 10 eV to 200 eV. Single differential and total electron emission cross sections are derived by integration over angle and electron energy and compared to the semi-empirical Hansen-Kocbach-Stolterfoht (HKS) model and a quantum mechanical calculation employing the first Born approximation with corrected boundary conditions (CB1). The CB1 provides the best prediction of double and single differential cross section, while total cross sections can be fitted with semi-empirical models. The cross sections of the three samples are proportional to their total number of valence electrons.

  6. Cluster observations of particle acceleration up to supra-thermal energies in the cusp region related to low-frequency wave activity - possible implications for the substorm initiation process

    NASA Astrophysics Data System (ADS)

    Vogiatzis, I. I.; Sarris, T. E.; Sarris, E. T.; Santolík, O.; Dandouras, I.; Robert, P.; Fritz, T. A.; Zong, Q.-G.; Zhang, H.

    2008-03-01

    The purpose of our study is to investigate the way particles are accelerated up to supra-thermal energies in the cusp diamagnetic cavities. For this reason we have examined a number of Cluster cusp crossings, originally identified by Zhang et al. (2005), for the years 2001 and 2002 using data from RAPID, STAFF, EFW, CIS, PEACE, and FGM experiments. In the present study we focus on two particular cusp crossings on 25 March 2002 and on 10 April 2002 which demonstrate in a clear way the general characteristics of the events in our survey. Both events exhibit very sharp spatial boundaries seen both in CNO (primarily single-charged oxygen of ionospheric origin based on CIS observations) and H+ flux increases within the RAPID energy range with the magnetic field intensity being anti-correlated. Unlike the first event, the second one shows also a moderate electron flux increase. The fact that the duskward electric field Ey has relatively low values <5 mV/m while the local wave activity is very intense provides a strong indication that particle energization is caused primarily by wave-particle interactions. The wave power spectra and propagation parameters during these cusp events are examined in detail. It is concluded that the high ion fluxes and at the same time the presence or absence of any sign of energization in the electrons clearly shows that the particle acceleration depends on the wave power near the local particle gyrofrequency and on the persistence of the wave-particle interaction process before particles escape from cusp region. Furthermore, the continuous existence of energetic O+ ions suggests that energetic O+ populations are of spatial nature at least for the eight events that we have studied so far.

  7. Investigating the limitations of tree species classification using the Combined Cluster and Discriminant Analysis method for low density ALS data from a dense forest region in Aggtelek (Hungary)

    NASA Astrophysics Data System (ADS)

    Koma, Zsófia; Deák, Márton; Kovács, József; Székely, Balázs; Kelemen, Kristóf; Standovár, Tibor

    2016-04-01

    Airborne Laser Scanning (ALS) is a widely used technology for forestry classification applications. However, single tree detection and species classification from low density ALS point cloud is limited in a dense forest region. In this study we investigate the division of a forest into homogenous groups at stand level. The study area is located in the Aggtelek karst region (Northeast Hungary) with a complex relief topography. The ALS dataset contained only 4 discrete echoes (at 2-4 pt/m2 density) from the study area during leaf-on season. Ground-truth measurements about canopy closure and proportion of tree species cover are available for every 70 meter in 500 square meter circular plots. In the first step, ALS data were processed and geometrical and intensity based features were calculated into a 5×5 meter raster based grid. The derived features contained: basic statistics of relative height, canopy RMS, echo ratio, openness, pulse penetration ratio, basic statistics of radiometric feature. In the second step the data were investigated using Combined Cluster and Discriminant Analysis (CCDA, Kovács et al., 2014). The CCDA method first determines a basic grouping for the multiple circle shaped sampling locations using hierarchical clustering and then for the arising grouping possibilities a core cycle is executed comparing the goodness of the investigated groupings with random ones. Out of these comparisons difference values arise, yielding information about the optimal grouping out of the investigated ones. If sub-groups are then further investigated, one might even find homogeneous groups. We found that low density ALS data classification into homogeneous groups are highly dependent on canopy closure, and the proportion of the dominant tree species. The presented results show high potential using CCDA for determination of homogenous separable groups in LiDAR based tree species classification. Aggtelek Karst/Slovakian Karst Caves" (HUSK/1101/221/0180, Aggtelek NP

  8. Sal k 4, a new allergen of Salsola kali, is profilin: a predictive value of conserved conformational regions in cross-reactivity with other plant-derived profilins.

    PubMed

    Assarehzadegan, Mohammad Ali; Amini, Akram; Sankian, Mojtaba; Tehrani, Mohsen; Jabbari, Farahzad; Varasteh, Abdolreza

    2010-01-01

    The aim of this study was to investigate a new allergen of Salsola kali, Sal k 4, and to investigate the predictive value of the conserved conformational regions in cross-reactivity with other plant-derived profilins. The Sal k 4-coding sequence was cloned, expressed, and purified by one-step Ni2+ affinity chromatography to recover high-purity target protein. We assessed cross-reactivity and predicted conserved conformational regions among rSal k 4 and other plant-derived profilins. Immunodetection and inhibition assays using 30 individual sera from S. kali allergic patients indicated that purified rSal k 4 might be the same as that in the crude extract. The results of inhibition assays among rSal k 4 and other plant-derived profilins were in accordance with the homology of the predicted conserved conformational regions. Amino acid sequence homology analysis showed that a high degree of IgE cross-reactivity among plant-derived profilins might depend on the predicted conserved conformational regions.

  9. Detailed ordering of markers localizing to the Xq26-Xqter region of the human X chromosome by the use of an interspecific Mus spretus mouse cross

    SciTech Connect

    Avner, P.; Amar, L.; Arnaud, D.; Hanauer, A.; Cambrou, J.

    1987-03-01

    Five probes localizing to the Xq26-Xqter region of the human X chromosome have been genetically mapped on the mouse X chromosome using an interspecific cross involving Mus spretus to a contiguous region lying proximally to the Tabby (Ta) locus. Pedigree and recombinational analysis establish the marker order as being Hprt-FIX-c11-G6PD-St14-1. The size of this contiguous region is such that the X-linked muscular dystrophy (mdx) mouse mutation probably maps within this segment. This in turn suggests that it is highly improbable that the mouse mdx locus represents a model for Duchenne muscular dystrophy (DMD). It is, however, compatible with the idea that this mutation may correspond in man to Emery Dreifuss muscular dystrophy. The high frequency of restriction fragment length polymorphisms found in this interspecific system for all the human cross-reacting probes examined up until now, using only a limited number of restriction enzymes, suggests that the Mus spretus mapping system may be of great potential value for establishing the linkage relationships existing in man when conserved chromosomal regions are concerned and human/mouse cross-reacting probes are available or can be obtained.

  10. Clustered data in sports research.

    PubMed

    Hayen, A

    2006-05-01

    Clustered, or dependent, data, arise commonly in sports medicine and sports science research, particularly in studies of sports injury and biomechanics, particularly in sports injury trials that are randomised at team or club level, in cross-sectional surveys in which groups of individuals are studied and in studies with repeated measures designs. Clustering, or positive correlation among responses, arises because responses and outcomes from the same cluster will usually be more similar than from different clusters. Study designs with clustering will usually required an increased sample size when compared to those without clustering. Ignoring clustering in statistical analyses can also lead to misleading conclusions, including incorrect confidence intervals and p-values. Appropriate statistical analyses for clustered data must be adopted. This paper gives some examples of clustered data and discusses the implications of clustering on the design and analysis of studies in sports medicine and sports science research.

  11. Hubble Space Telescope (HST) observations of Saturn's F ring region during the 1995 ring--plane crossings

    NASA Astrophysics Data System (ADS)

    McGhee, C. A.; Nicholson, P. D.; French, R. G.; Hall, K. J.

    1998-09-01

    HST observations of Saturn's ring--plane crossings in May, August and November 1995 revealed the presence of multiple objects orbiting in or near the F ring (Nicholson et\\ al.; Bosh and Rivkin 1996, Science 272, 509; 518). The combination of the May and August data sets, along with refined ring template subtraction, has allowed us to improve our understanding of the distribution of these suspected F ring clumps. In addition to new orbits for objects S/1995 S5, S6 and S7, we have obtained measurements and orbital parameters for S9, first reported in data taken at the CFHT (Roddier et\\ al. 1995, IAUC 6515), and measurements of a host of fainter objects in both HST data sets. An additional 3 F--ring objects in May and 5 in August were found to account for a total of ~ 90 of these fainter clump measurements. S/1995 S1 orbits very close to Atlas, well inside the F ring; S7 and S9 appear to be coorbital with Prometheus; while S3 and S6 fall ~ 500 km on either side of the F ring. These results lend support to Cuzzi and Burns' (1988, Icarus 74, 284) hypothesis of a belt of moonlet--sized (or smaller) objects occupying the entire radial region between Pandora and Prometheus. Object & Semimajor axis (km) & e & RMS residual (km) S/1995 S1 & 137,529+/-87 & 0 & 528.43 Atlas & 137,678 &0 & S/1995 S7 & 139,371+/-93 &0 & 250.64 Prometheus& 139,377.2+/-0.1 & 0.0024 & 214.91 S7+May 358 & 139,382.4+/-0.3 & 0.0024 & 389.67 S/1995 S9 & 139,445+/-139 & 0 & 362.95 S/1995 S6 & 139,594+/-75 & 0 & 350.67 S/1995 S5 & 139,824+/-88 & 0.0029 & 329.44 F ring & 140,209 & 0.0029 & S/1995 S3 & 140,742+/-135 & 0 & 570.33 Pandora & 141,714.8+/-0.2 & 0.0044 & 314.06

  12. Definition of the region on NS3 which contains multiple epitopes recognized by dengue virus serotype-cross-reactive and flavivirus-cross-reactive, HLA-DPw2-restricted CD4+ T cell clones.

    PubMed

    Okamoto, Y; Kurane, I; Leporati, A M; Ennis, F A

    1998-04-01

    The epitopes recognized by six CD4+ CD8- cytotoxic T lymphocyte (CTL) clones established from a dengue-3 virus-immune donor were defined. (i) Three CTL clones, JK10, JK34 and JK39, were cross-reactive for dengue virus types 1-4. (ii) One clone, JK28, was cross-reactive for dengue virus types 1-4 and West Nile virus. (iii) Two clones, JK26 and JK49, were cross-reactive for dengue virus types 1-4, West Nile virus and yellow fever virus. The clones, except for JK49, recognized the same epitope on NS3 in an HLA-DPw2-restricted fashion. The smallest synthetic peptide recognized by the five CTL clones was a 10 aa peptide which comprises aa 255-264 on dengue virus NS3. JK49 recognized the overlapping epitope which comprises aa 257-266 in an HLA-DPw2-restricted fashion. Analysis of T cell receptor (TCR) usage by these T cell clones revealed that (i) JK10 and JK34 use V alpha11, and JK34 and JK28 use V beta23, and (ii) the amino acid sequences of the V(D)J junctional region of the TCR were different among these five CTL clones. There were, however, single amino acid conservations among TCRs of some of these T cell clones. These results indicate that the region on NS3 which comprises aa 255-266 contains multiple epitopes recognized by dengue serotype-cross-reactive and flavivirus-cross-reactive CD4+ CTL in an HLA-DPw2-restricted fashion and that a single epitope can be recognized by T cells which have heterogeneous virus specificities.

  13. A specific mutation in the promoter region of the silent cel cluster accounts for the appearance of lactose-utilizing Lactococcus lactis MG1363.

    PubMed

    Solopova, Ana; Bachmann, Herwig; Teusink, Bas; Kok, Jan; Neves, Ana Rute; Kuipers, Oscar P

    2012-08-01

    The Lactococcus lactis laboratory strain MG1363 has been described to be unable to utilize lactose. However, in a rich medium supplemented with lactose as the sole carbon source, it starts to grow after prolonged incubation periods. Transcriptome analyses showed that L. lactis MG1363 Lac(+) cells expressed celB, encoding a putative cellobiose-specific phosphotransferase system (PTS) IIC component, which is normally silent in MG1363 Lac(-) cells. Nucleotide sequence analysis of the cel cluster of a Lac(+) isolate revealed a change from one of the guanines to adenine in the promoter region. We showed here that one particular mutation, taking place at increased frequency, accounts for the lactose-utilizing phenotype occurring in MG1363 cultures. The G-to-A transition creates a -10 element at an optimal distance from the -35 element. Thus, a fully active promoter is created, allowing transcription of the otherwise cryptic cluster. Nuclear magnetic resonance (NMR) spectroscopy results show that MG1363 Lac(+) uses a novel pathway of lactose utilization.

  14. The Nine Genes of the Nocardia lactamdurans Cephamycin Cluster Are Transcribed into Large mRNAs from Three Promoters, Two of Them Located in a Bidirectional Promoter Region

    PubMed Central

    Enguita, Francisco J.; Coque, Juan Jose R.; Liras, Paloma; Martin, Juan F.

    1998-01-01

    The nine biosynthesis genes of the Nocardia lactamdurans cephamycin cluster are expressed as three different mRNAs initiating at promoters latp, cefDp, and pcbABp, as shown by low-resolution S1 nuclease protection assays and Northern blotting analysis. Bidirectional expression occurred from divergent promoters (latp and cefDp) located in a 629-bp intergenic region that contains three heptameric direct repeats similar to those recognized by members of the SARP (Streptomyces antibiotic regulatory proteins) family. The lat gene is transcribed in a single monocistronic transcript initiating at latp. A second unusually long polycistronic mRNA (more than 16 kb) corresponding to six biosynthesis genes (pcbAB, pcbC, cmcI, cmcJ, cefF, and cmcH) started at pcbABp. A third polycistronic mRNA corresponding to the cefD and cefE genes started at cefDp. PMID:9765587

  15. Independent metal-thiolate cluster formation in C-terminal Cys-rich region of a rice type 1 metallothionein isoform.

    PubMed

    Malekzadeh, Rahim; Shahpiri, Azar

    2017-03-01

    In this study we examined the independent self assembly of metal-binding in C-terminal Cys- rich region of a type 1 metallothionein (MT) isoform from rice (OsMTI-1b). To this end the N-terminal of OsMTI-1b (C-OsMTI-1b) was heterologously expressed in Escherichia coli as fusion protein with glutathione-S-transferase (GST). As compared with control (The E. coli cells containing pET41a without gene), transgenic E. coli cells expressing GST-C-OsMTI-1b accumulated more Ni(2+), Cd(2+), and Zn(2+) from culture medium and showed increased tolerance against these metals. The recombinant GST-C-OsMTI-1b was purified using affinity chromatography. According to in vitro assays the protein GST-C-OsMTI-1b was able to form complexes with Ni(2+), Cd(2+) and Zn(2+). These results demonstrate the formation of independent metal-thiolate cluster at C-terminal Cys-rich region of OsMTI-1b without participation of N-terminal Cys-rich region.

  16. Assessment of climate change impacts on watershed in cold-arid region: an integrated multi-GCM-based stochastic weather generator and stepwise cluster analysis method

    NASA Astrophysics Data System (ADS)

    Zhuang, X. W.; Li, Y. P.; Huang, G. H.; Liu, J.

    2016-07-01

    An integrated multi-GCM-based stochastic weather generator and stepwise cluster analysis (MGCM-SWG-SCA) method is developed, through incorporating multiple global climate models (MGCM), stochastic weather generator (SWG), and stepwise-clustered hydrological model (SCHM) within a general framework. MGCM-SWG-SCA can investigate uncertainties of projected climate changes as well as create watershed-scale climate projections from large-scale variables. It can also assess climate change impacts on hydrological processes and capture nonlinear relationship between input variables and outputs in watershed systems. MGCM-SWG-SCA is then applied to the Kaidu watershed with cold-arid characteristics in the Xinjiang Uyghur Autonomous Region of northwest China, for demonstrating its efficiency. Results reveal that the variability of streamflow is mainly affected by (1) temperature change during spring, (2) precipitation change during winter, and (3) both temperature and precipitation changes in summer and autumn. Results also disclose that: (1) the projected minimum and maximum temperatures and precipitation from MGCM change with seasons in different ways; (2) various climate change projections can reproduce the seasonal variability of watershed-scale climate series; (3) SCHM can simulate daily streamflow with a satisfactory degree, and a significant increasing trend of streamflow is indicated from future (2015-2035) to validation (2006-2011) periods; (4) the streamflow can vary under different climate change projections. The findings can be explained that, for the Kaidu watershed located in the cold-arid region, glacier melt is mainly related to temperature changes and precipitation changes can directly cause the variability of streamflow.

  17. Dust in Cluster Dwarf Elliptical Galaxies

    NASA Astrophysics Data System (ADS)

    De Looze, I.; Baes, M.; Fritz, J.; Verstappen, J.; Bendo, G. J.; Bianchi, S.; Bomans, D. J.; Boselli, A.; Clemens, M.; Corbelli, E.; Cortese, L.; Dariush, A.; Davies, J. I.; di Serego Alighieri, S.; Fadda, D.; Garcia-Appadoo, D. A.; Gavazzi, G.; Giovanardi, C.; Grossi, M.; Hughes, T. M.; Hunt, L. K.; Jones, A. P.; Madden, S.; Magrini, L.; Pierini, D.; Pohlen, M.; Sabatini, S.; Smith, M. W. L.; Vlahakis, C.; Xilouris, E. M.; Zibetti, S.

    Based on single cross-scan data of the Herschel Virgo Cluster Survey, we report the first detections of dust in cluster early-type dwarf galaxies: VCC 209, VCC 781 and VCC 951. All three galaxies have dust masses M d ≈ 105 - 106 M⊙ and average dust temperatures ≈ 16-20 K. Since these three early-type dwarfs reside in densely crowded regions close to the center of the Virgo cluster, and several H I-detected dwarfs in the outskirts of Virgo were not detected by Herschel(implying a dust content < 104 M⊙), this might imply that dust in dwarfs is more closely related to the molecular gas, which is more centrally peaked in a galaxy's potential well and therefore, not easily removed by any stripping mechanism. We conclude that the removal of interstellar dust from these early-type dwarfs appears to be less efficient than the removal of the H I gas.

  18. Consumer clusters in Denmark based on coarse vegetable intake frequency, explained by hedonics, socio-demographic, health and food lifestyle factors. A cross-sectional national survey.

    PubMed

    Beck, Tove K; Jensen, Sidsel; Simmelsgaard, Sonni Hansen; Kjeldsen, Chris; Kidmose, Ulla

    2015-08-01

    Vegetable intake seems to play a protective role against major lifestyle diseases. Despite this, the Danish population usually eats far less than the recommended daily intake. The present study focused on the intake of 17 coarse vegetables and the potential barriers limiting their intake. The present study drew upon a large Danish survey (n = 1079) to study the intake of coarse vegetables among Danish consumers. Four population clusters were identified based on their intake of 17 different coarse vegetables, and profiled according to hedonics, socio-demographic, health, and food lifestyle factors. The four clusters were characterized by a very low intake frequency of coarse vegetables ('low frequency'), a low intake frequency of coarse vegetables; but high intake frequency of carrots ('carrot eaters'), a moderate coarse vegetable intake frequency and high intake frequency of beetroot ('beetroot eaters'), and a high intake frequency of all coarse vegetables ('high frequency'). There was a relationship between reported liking and reported intake frequency for all tested vegetables. Preference for foods with a sweet, salty or bitter taste, in general, was also identified to be decisive for the reported vegetable intake, as these differed across the clusters. Each cluster had distinct socio-demographic, health and food lifestyle profiles. 'Low frequency' was characterized by uninvolved consumers with lack of interest in food, 'carrot eaters' vegetable intake was driven by health aspects, 'beetroot eaters' were characterized as traditional food consumers, and 'high frequency' were individuals with a strong food engagement and high vegetable liking. 'Low frequency' identified more barriers than other consumer clusters and specifically regarded low availability of pre-cut/prepared coarse vegetables on the market as a barrier. Across all clusters a low culinary knowledge was identified as the main barrier.

  19. Existence of G-quadruplex structures in promoter region of oncogenes confirmed by G-quadruplex DNA cross-linking strategy

    PubMed Central

    Yuan, Libo; Tian, Tian; Chen, Yuqi; Yan, Shengyong; Xing, Xiwen; Zhang, Zhengan; Zhai, Qianqian; Xu, Liang; Wang, Shaoru; Weng, Xiaocheng; Yuan, Bifeng; Feng, Yuqi; Zhou, Xiang

    2013-01-01

    Existence of G-quadruplex DNA in vivo always attract widespread interest in the field of biology and biological chemistry. We reported our findings for the existence of G-quadruplex structures in promoter region of oncogenes confirmed by G-quadruplex DNA cross-linking strategy. Probes for selective G-quadruplex cross-linking was designed and synthesized that show high selectivity for G-quadruplex cross-linking. Further biological studies demonstrated its good inhibition activity against murine melanoma cells. To further investigate if G-quadruplex DNA was formed in vivo and as the target, a derivative was synthesized and pull-down process toward chromosome DNAs combined with circular dichroism and high throughput deep sequencing were performed. Several simulated intracellular conditions, including X. laevis oocytes, Ficoll 70 and PEG, was used to investigate the compound's pure cross-linking ability upon preformed G-quadruplex. Thus, as a potent G-quadruplex cross-linking agent, our strategy provided both valuable evidence of G-quadruplex structures in vivo and intense potential in anti-cancer therapy. PMID:23657205

  20. 241 Am ( n ,γ) cross section in the neutron energy region between 0.02 eV and 300 keV

    NASA Astrophysics Data System (ADS)

    Jandel, M.; Bredeweg, T. A.; Bond, E. M.; Chadwick, M. B.; Clement, R. R.; Couture, A.; O'Donnell, J. M.; Haight, R. C.; Reifarth, R.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Macri, R. A.; Wu, C. Y.; Becker, J. A.

    2008-04-01

    The Detector for Advanced Neutron Capture Experiments (DANCE) at Los Alamos National Laboratory (LANL) was used for a neutron capture cross section measurement on 241 Am . The high granularity of the DANCE array (160 BaF2 detectors in a 4π geometry) enables an efficient detection of prompt gamma rays following neutron capture. The preliminary results on the 241 Am ( n ,γ) cross section are presented from 0.02 eV to 300 keV. The cross section at thermal energy E n = 0.0253 eV was determined to be 665±33 barns. Resonance parameters were obtained using the SAMMY7 fit to the measured cross section in the resonance region. Significant discrepancies were found between our results and data evaluations for the first three lowest lying resonances. The cross section for neutrons with E n >l keV agrees well with the ENDF/B-VII.0 and JENDL-3.3 evaluations.

  1. {sup 241}Am(n,{gamma}) cross section in the neutron energy region between 0.02 eV and 300 keV

    SciTech Connect

    Jandel, M.; Bredeweg, T. A.; Bond, E. M.; Chadwick, M. B.; Clement, R. R.; Couture, A.; O' Donnell, J. M.; Haight, R. C.; Reifarth, R.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Macri, R. A.; Wu, C. Y.; Becker, J. A.

    2008-04-17

    The Detector for Advanced Neutron Capture Experiments (DANCE) at Los Alamos National Laboratory (LANL) was used for a neutron capture cross section measurement on {sup 241}Am. The high granularity of the DANCE array (160 BaF2 detectors in a 4{pi} geometry) enables an efficient detection of prompt gamma rays following neutron capture. The preliminary results on the {sup 241}Am(n,{gamma}) cross section are presented from 0.02 eV to 300 keV. The cross section at thermal energy E{sub n} = 0.0253 eV was determined to be 665{+-}33 barns. Resonance parameters were obtained using the SAMMY7 fit to the measured cross section in the resonance region. Significant discrepancies were found between our results and data evaluations for the first three lowest lying resonances. The cross section for neutrons with E{sub n}>l keV agrees well with the ENDF/B-VII.0 and JENDL-3.3 evaluations.

  2. Free stream turbulence and density ratio effects on the interaction region of a jet in a cross flow

    NASA Technical Reports Server (NTRS)

    Wark, C. E.; Foss, J. F.

    1984-01-01

    Jets of low temperature air are introduced into the aft sections of gas turbine combustors for the purpose of cooling the high temperature gases and quenching the combustion reactions. Research studies, motivated by this complex flow field, have been executed by introducing a heated jet into the cross stream of a wind tunnel. The investigation by Kamotani and Greber stands as a prime example of such investigations and it serves as the principal reference for the present study. The low disturbance level of the cross stream, in their study and in similar research investigations, is compatible with an interest in identifying the basic features of this flow field. The influence of the prototypes' strongly disturbed cross flow is not, however, made apparent in these prior investigations.

  3. Absolute elastic differential electron scattering cross sections in the intermediate energy region. III - SF6 and UF6

    NASA Technical Reports Server (NTRS)

    Srivastava, S. K.; Trajmar, S.; Chutjian, A.; Williams, W.

    1976-01-01

    A recently developed technique has been used to measure the ratios of elastic differential electron scattering cross sections (DCS) for SF6 and UF6 to those of He at electron impact energies of 5, 10, 15, 20, 30, 40, 50, 60, and 75 eV and at scattering angles of 20 to 135 deg. In order to obtain the absolute values of DCS from these ratios, He DCS of McConkey and Preston have been employed in the 20 to 90 deg range. At angles in the 90 to 135 deg range the recently determined cross sections of Srivastava and Trajmar have been utilized. From these DCS, elastic integral and momentum transfer cross sections have been obtained.

  4. Two-photon absorption cross sections within equation-of-motion coupled-cluster formalism using resolution-of-the-identity and Cholesky decomposition representations: Theory, implementation, and benchmarks

    NASA Astrophysics Data System (ADS)

    Nanda, Kaushik D.; Krylov, Anna I.

    2015-02-01

    The equation-of-motion coupled-cluster (EOM-CC) methods provide a robust description of electronically excited states and their properties. Here, we present a formalism for two-photon absorption (2PA) cross sections for the equation-of-motion for excitation energies CC with single and double substitutions (EOM-CC for electronically excited states with single and double substitutions) wave functions. Rather than the response theory formulation, we employ the expectation-value approach which is commonly used within EOM-CC, configuration interaction, and algebraic diagrammatic construction frameworks. In addition to canonical implementation, we also exploit resolution-of-the-identity (RI) and Cholesky decomposition (CD) for the electron-repulsion integrals to reduce memory requirements and to increase parallel efficiency. The new methods are benchmarked against the CCSD and CC3 response theories for several small molecules. We found that the expectation-value 2PA cross sections are within 5% from the quadratic response CCSD values. The RI and CD approximations lead to small errors relative to the canonical implementation (less than 4%) while affording computational savings. RI/CD successfully address the well-known issue of large basis set requirements for 2PA cross sections calculations. The capabilities of the new code are illustrated by calculations of the 2PA cross sections for model chromophores of the photoactive yellow and green fluorescent proteins.

  5. Two-photon absorption cross sections within equation-of-motion coupled-cluster formalism using resolution-of-the-identity and Cholesky decomposition representations: Theory, implementation, and benchmarks.

    PubMed

    Nanda, Kaushik D; Krylov, Anna I

    2015-02-14

    The equation-of-motion coupled-cluster (EOM-CC) methods provide a robust description of electronically excited states and their properties. Here, we present a formalism for two-photon absorption (2PA) cross sections for the equation-of-motion for excitation energies CC with single and double substitutions (EOM-CC for electronically excited states with single and double substitutions) wave functions. Rather than the response theory formulation, we employ the expectation-value approach which is commonly used within EOM-CC, configuration interaction, and algebraic diagrammatic construction frameworks. In addition to canonical implementation, we also exploit resolution-of-the-identity (RI) and Cholesky decomposition (CD) for the electron-repulsion integrals to reduce memory requirements and to increase parallel efficiency. The new methods are benchmarked against the CCSD and CC3 response theories for several small molecules. We found that the expectation-value 2PA cross sections are within 5% from the quadratic response CCSD values. The RI and CD approximations lead to small errors relative to the canonical implementation (less than 4%) while affording computational savings. RI/CD successfully address the well-known issue of large basis set requirements for 2PA cross sections calculations. The capabilities of the new code are illustrated by calculations of the 2PA cross sections for model chromophores of the photoactive yellow and green fluorescent proteins.

  6. Two-photon absorption cross sections within equation-of-motion coupled-cluster formalism using resolution-of-the-identity and Cholesky decomposition representations: Theory, implementation, and benchmarks

    SciTech Connect

    Nanda, Kaushik D.; Krylov, Anna I.

    2015-02-14

    The equation-of-motion coupled-cluster (EOM-CC) methods provide a robust description of electronically excited states and their properties. Here, we present a formalism for two-photon absorption (2PA) cross sections for the equation-of-motion for excitation energies CC with single and double substitutions (EOM-CC for electronically excited states with single and double substitutions) wave functions. Rather than the response theory formulation, we employ the expectation-value approach which is commonly used within EOM-CC, configuration interaction, and algebraic diagrammatic construction frameworks. In addition to canonical implementation, we also exploit resolution-of-the-identity (RI) and Cholesky decomposition (CD) for the electron-repulsion integrals to reduce memory requirements and to increase parallel efficiency. The new methods are benchmarked against the CCSD and CC3 response theories for several small molecules. We found that the expectation-value 2PA cross sections are within 5% from the quadratic response CCSD values. The RI and CD approximations lead to small errors relative to the canonical implementation (less than 4%) while affording computational savings. RI/CD successfully address the well-known issue of large basis set requirements for 2PA cross sections calculations. The capabilities of the new code are illustrated by calculations of the 2PA cross sections for model chromophores of the photoactive yellow and green fluorescent proteins.

  7. Tungsten Cluster Migration on Nanoparticles: Minimum Energy Pathway and Migration Mechanism

    SciTech Connect

    Chen, Dong; Hu, Wangyu; Gao, Fei; Deng, Huiqiu; Sun, Lixian

    2011-03-02

    Transition state searches have been employed to investigate the migration mechanisms of W clusters on W nanoparticles, and to determine the corresponding migration energies for the possible migration paths of these clusters. The tungsten clusters containing up to four adatoms are found to prefer 2D-compact structures with relatively low binding energies. The effect of interface and vertex regions on the migration behavior of the clusters is significantly strong, as compared to that of nanoparticle size. The migration mechanisms are quite different when the clusters are located at the center of the nanoparticle and near the interface or vertex areas. Near the interfaces and vertex areas, the substrate atoms tend to participate in the migration processes of the clusters, and can join the adatoms to form a larger cluster or lead to the dissociation of a cluster via the exchange mechanism, which results in the adatom crossing the facets. The lowest energy paths are used to be determined the energy barriers for W cluster migrations (from 1- to 4-atoms) on the facets, edges and vertex regions. The calculated energy barriers for the trimers suggest that the concerted migration is more probable than the successive jumping of a single adatom in the clusters. In addition, it of interest to note that the dimer shearing is a dominant migration mechanism for the tetramer, but needs to overcome a relatively higher migration energy than other clusters.

  8. Comparative analysis of the locus control region of the rabbit beta-like gene cluster: HS3 increases transient expression of an embryonic epsilon-globin gene.

    PubMed Central

    Hardison, R; Xu, J; Jackson, J; Mansberger, J; Selifonova, O; Grotch, B; Biesecker, J; Petrykowska, H; Miller, W

    1993-01-01

    The rabbit homolog to the locus control region (LCR) of the human beta-like globin gene cluster was isolated, and long segments containing the DNase I hypersensitive sites (HS) were sequenced. The order and spacing of HS4, HS3, HS2 and HS1 are conserved between rabbit and human. Alignment of these sequences with their homologs from human, goat, and mouse shows that very long segments of DNA match between species, for over a thousand base pairs on either side of the previously identified functional cores, indicating that some important functions are found outside the cores. The activity of rabbit HS2 and HS3 was tested by attaching each to a novel reporter gene constructed by inserting the luciferase coding region into the rabbit epsilon-globin gene. In contrast to previous reports showing no effect of human or mouse HS3 on transient expression, both the rabbit HS2 and HS3 DNA fragments separately increased transient expression from the epsilon-luciferase hybrid gene and expression from stably integrated constructs in K562 erythroleukemia cells. PMID:8464710

  9. Association of a variant in the CHRNA5-A3-B4 gene cluster region to heavy smoking in the Italian population

    PubMed Central

    Sorice, Rossella; Bione, Silvia; Sansanelli, Serena; Ulivi, Sheila; Athanasakis, Emmanouil; Lanzara, Carmela; Nutile, Teresa; Sala, Cinzia; Camaschella, Clara; D'Adamo, Pio; Gasparini, Paolo; Ciullo, Marina; Toniolo, Daniela

    2011-01-01

    Large-scale population studies have established that genetic factors contribute to individual differences in smoking behavior. Linkage and genome-wide association studies have shown many chromosomal regions and genes associated with different smoking behaviors. One study was the association of single-nucleotide polymorphisms (SNPs) in the CHRNA5-A3-B4 gene cluster to nicotine addiction. Here, we report a replication of this association in the Italian population represented by three genetically isolated populations. One, the Val Borbera, is a genetic isolate from North-Western Italy; the Cilento population, is located in South-Western Italy; and the Carlantino village is located in South-Eastern Italy. Owing to their position and their isolation, the three populations have a different environment, different history and genetic structure. The variant A of the rs1051730 SNP was significantly associated with smoking quantity in two populations, Val Borbera and Cilento, no association was found in Carlantino population probably because difference in LD pattern in the variant region. PMID:21248747

  10. Size resolved infrared spectroscopy of Na(CH3OH)n (n = 4-7) clusters in the OH stretching region: unravelling the interaction of methanol clusters with a sodium atom and the emergence of the solvated electron.

    PubMed

    Forck, Richard M; Pradzynski, Christoph C; Wolff, Sabine; Ončák, Milan; Slavíček, Petr; Zeuch, Thomas

    2012-03-07

    Size resolved IR action spectra of neutral sodium doped methanol clusters have been measured using IR excitation modulated photoionisation mass spectroscopy. The Na(CH(3)OH)(n) clusters were generated in a supersonic He seeded expansion of methanol by subsequent Na doping in a pick-up cell. A combined analysis of IR action spectra, IP evolutions and harmonic predictions of IR spectra (using density functional theory) of the most stable structures revealed that for n = 4, 5 structures with an exterior Na atom showing high ionisation potentials (IPs) of ~4 eV dominate, while for n = 6, 7 clusters with lower IPs (~3.2 eV) featuring fully solvated Na atoms and solvated electrons emerge and dominate the IR action spectra. For n = 4 simulations of photoionisation spectra using an ab initio MD approach confirm the dominance of exterior structures and explain the previously reported appearance IP of 3.48 eV by small fractions of clusters with partly solvated Na atoms. Only for this cluster size a shift in the isomer composition with cluster temperature has been observed, which may be related to kinetic stabilisation of less Na solvated clusters at low temperatures. Features of slow fragmentation dynamics of cationic Na(+)(CH(3)OH)(6) clusters have been observed for the photoionisation near the adiabatic limit. This finding points to the relevance of previously proposed non-vertical photoionisation dynamics of this system.

  11. Evaluation of the γn→π⁻p differential cross section in the Δ-isobar region

    DOE PAGES

    Briscoe, W. J.; Kudryavtsev, A. E.; Pedroni, P.; ...

    2012-12-20

    Differential cross sections for the process γn→π⁻p have been extracted from MAMI-B measurements of γd→π⁻pp, accounting for final-state interaction effects, using a diagrammatic technique taking into account the NN and πN final-state interaction amplitudes. Results are compared to previous measurements of the inverse process, π⁻p→nγ, and recent multipole analyses.

  12. A Cross-Gradient Constrained Inversion of Seismic and Magnetotelluric Data in the Parkfield Region of California

    NASA Astrophysics Data System (ADS)

    Bennington, N. L.; Thurber, C. H.; Bedrosian, P. A.

    2009-12-01

    Model nonuniqueness and imperfect resolution are pervasive problems in the inversion of geophysical data. We are exploring the utility of structural constraints employing a cross-gradients penalty function to improve models of fault zone structure along the San Andreas fault in the Parkfield, California area. Previously, individual seismic and resistivity models at SAFOD were completed that showed significant spatial similarity between main features. We will capitalize on this likeness by developing a joint inversion scheme that uses the cross gradient penalty function to achieve structurally similar images that fit both the resistivity and seismic models without forcing model similarity where none exists. The new inversion code, tomoDDMT, which merges the seismic inversion code, tomoDD, and the magnetotelluric (MT) inversion code, Occam2DMT, will be used to carry out the inversion. Due to resolution differences, seismic and resistivity models are inverted for under varying gridding schemes. This difference in gridding will be overcome by projecting model values for both onto a regular, much finer grid thereby linking the two models. Calculation of the cross-gradient constraint will be completed on this “common” grid and these values will be projected back to the seismic and resistivity model spaces. A simultaneous solution will then be carried out for the seismic and resistivity models under application of the cross-gradient constraint. Inversions in Occam2DMT are solved using Cholesky factorization. To increase the speed of the inversion, tomoDDMT will employ the LSQR algorithm for the simultaneous solution of both models.

  13. Analysis of the long control region of bovine papillomavirus type 1 associated with sarcoids in equine hosts indicates multiple cross-species transmission events and phylogeographical structure.

    PubMed

    Trewby, Hannah; Ayele, Gizachew; Borzacchiello, Giuseppe; Brandt, Sabine; Campo, M Saveria; Del Fava, Claudia; Marais, Johan; Leonardi, Leonardo; Vanselow, Barbara; Biek, Roman; Nasir, Lubna

    2014-12-01

    Papillomaviruses are a family of slowly evolving DNA viruses and their evolution is commonly linked to that of their host species. However, whilst bovine papillomavirus-1 (BPV-1) primarily causes warts in its natural host, the cow, it can also cause locally aggressive and invasive skin tumours in equids, known as sarcoids, and thus provides a rare contemporary example of cross-species transmission of a papillomavirus. Here, we describe the first phylogenetic analysis of BPV-1 in equine sarcoids to our knowledge, allowing us to explore the evolutionary history of BPV-1 and investigate its cross-species association with equids. A phylogenetic analysis of the BPV-1 transcriptional promoter region (the long control region or LCR) was conducted on 15 bovine and 116 equine samples from four continents. Incorporating previous estimates for evolutionary rates in papillomavirus implied that the genetic diversity in the LCR variants was ancient and predated domestication of both equids and cattle. The phylogeny demonstrated geographical segregation into an ancestral group (African, South American and Australian samples), and a more recently derived, largely European clade. Whilst our data are consistent with BPV-1 originating in cattle, we found evidence of multiple, probably relatively recent, cross-species transmission events into horses. We also demonstrated the high prevalence of one particular sequence variant (variant 20), and suggest this may indicate that this variant shows a fitness advantage in equids. Although strong host specificity remains the norm in papillomaviruses, our results demonstrate that exceptions to this rule exist and can become epidemiologically relevant.

  14. CLUSTER CHEMISTRY

    SciTech Connect

    Muetterties, Earl L.

    1980-05-01

    Metal cluster chemistry is one of the most rapidly developing areas of inorganic and organometallic chemistry. Prior to 1960 only a few metal clusters were well characterized. However, shortly after the early development of boron cluster chemistry, the field of metal cluster chemistry began to grow at a very rapid rate and a structural and a qualitative theoretical understanding of clusters came quickly. Analyzed here is the chemistry and the general significance of clusters with particular emphasis on the cluster research within my group. The importance of coordinately unsaturated, very reactive metal clusters is the major subject of discussion.

  15. Comparison of intraclass correlation coefficient estimates and standard errors between using cross-sectional and repeated measurement data: the Safety Check cluster randomized trial.

    PubMed

    Ip, Edward H; Wasserman, Richard; Barkin, Shari

    2011-03-01

    Designing cluster randomized trials in clinical studies often requires accurate estimates of intraclass correlation, which quantifies the strength of correlation between units, such as participants, within a cluster, such as a practice. Published ICC estimates, even when available, often suffer from the problem of wide confidence intervals. Using data from a national, randomized, controlled study concerning violence prevention for children--the Safety Check--we compare the ICC values derived from two approaches only baseline data and using both baseline and follow-up data. Using a variance component decomposition approach, the latter method allows flexibility in handling complex data sets. For example, it allows for shifts in the outcome variable over time and for an unbalanced cluster design. Furthermore, we evaluate the large-sample formula for ICC estimates and standard errors using the bootstrap method. Our findings suggest that ICC estimates range from 0.012 to 0.11 for providers within practice and range from 0.018 to 0.11 for families within provider. The estimates derived from the baseline-only and repeated-measurements approaches agree quite well except in cases in which variation over repeated measurements is large. The reductions in the widths of ICC confidence limits from using repeated measurement over baseline only are, respectively, 62% and 42% at the practice and provider levels. The contribution of this paper therefore includes two elements, which are a methodology for improving the accuracy of ICC, and the reporting of such quantities for pediatric and other researchers who are interested in designing clustered randomized trials similar to the current study.

  16. Do foreign exchange and equity markets co-move in Latin American region? Detrended cross-correlation approach

    NASA Astrophysics Data System (ADS)

    Bashir, Usman; Yu, Yugang; Hussain, Muntazir; Zebende, Gilney F.

    2016-11-01

    This paper investigates the dynamics of the relationship between foreign exchange markets and stock markets through time varying co-movements. In this sense, we analyzed the time series monthly of Latin American countries for the period from 1991 to 2015. Furthermore, we apply Granger causality to verify the direction of causality between foreign exchange and stock market and detrended cross-correlation approach (ρDCCA) for any co-movements at different time scales. Our empirical results suggest a positive cross correlation between exchange rate and stock price for all Latin American countries. The findings reveal two clear patterns of correlation. First, Brazil and Argentina have positive correlation in both short and long time frames. Second, the remaining countries are negatively correlated in shorter time scale, gradually moving to positive. This paper contributes to the field in three ways. First, we verified the co-movements of exchange rate and stock prices that were rarely discussed in previous empirical studies. Second, ρDCCA coefficient is a robust and powerful methodology to measure the cross correlation when dealing with non stationarity of time series. Third, most of the studies employed one or two time scales using co-integration and vector autoregressive approaches. Not much is known about the co-movements at varying time scales between foreign exchange and stock markets. ρDCCA coefficient facilitates the understanding of its explanatory depth.

  17. COMPARING DENSE GALAXY CLUSTER REDSHIFT SURVEYS WITH WEAK-LENSING MAPS

    SciTech Connect

    Hwang, Ho Seong; Geller, Margaret J.; Zahid, H. Jabran; Diaferio, Antonaldo; Rines, Kenneth J. E-mail: mgeller@cfa.harvard.edu E-mail: diaferio@ph.unito.it

    2014-12-20

    We use dense redshift surveys of nine galaxy clusters at z ∼ 0.2 to compare the galaxy distribution in each system with the projected matter distribution from weak lensing. By combining 2087 new MMT/Hectospec redshifts and the data in the literature, we construct spectroscopic samples within the region of weak-lensing maps of high (70%-89%) and uniform completeness. With these dense redshift surveys, we construct galaxy number density maps using several galaxy subsamples. The shape of the main cluster concentration in the weak-lensing maps is similar to the global morphology of the number density maps based on cluster members alone, mainly dominated by red members. We cross-correlate the galaxy number density maps with the weak-lensing maps. The cross-correlation signal when we include foreground and background galaxies at 0.5z {sub cl} < z < 2z {sub cl} is 10%-23% larger than for cluster members alone at the cluster virial radius. The excess can be as high as 30% depending on the cluster. Cross-correlating the galaxy number density and weak-lensing maps suggests that superimposed structures close to the cluster in redshift space contribute more significantly to the excess cross-correlation signal than unrelated large-scale structure along the line of sight. Interestingly, the weak-lensing mass profiles are not well constrained for the clusters with the largest cross-correlation signal excesses (>20% for A383, A689, and A750). The fractional excess in the cross-correlation signal including foreground and background structures could be a useful proxy for assessing the reliability of weak-lensing cluster mass estimates.

  18. Hydroxylamine assimilation by Rhodobacter capsulatus E1F1. requirement of the hcp gene (hybrid cluster protein) located in the nitrate assimilation nas gene region for hydroxylamine reduction.

    PubMed

    Cabello, Purificación; Pino, Carmen; Olmo-Mira, M Francisca; Castillo, Francisco; Roldán, M Dolores; Moreno-Vivián, Conrado

    2004-10-29

    Rhodobacter capsulatus E1F1 grows phototrophically with nitrate as nitrogen source. Using primers designed for conserved motifs in bacterial assimilatory nitrate reductases, a 450-bp DNA was amplified by PCR and used for the screening of a genomic library. A cosmid carrying an insert with four SalI fragments of 2.8, 4.1, 4.5, and 5.8 kb was isolated, and DNA sequencing revealed that it contains a nitrate assimilation (nas) gene region, including the hcp gene coding for a hybrid cluster protein (HCP). Expression of hcp is probably regulated by a nitrite-sensitive repressor encoded by the adjacent nsrR gene. A His(6)-HCP was overproduced in Escherichia coli and purified. HCP contained about 6 iron and 4 labile sulfide atoms per molecule, in agreement with the presence of both [2Fe-2S] and [4Fe-2S-2O] clusters, and showed hydroxylamine reductase activity, forming ammonia in vitro with methyl viologen as reductant. The apparent K(m) values for NH(2)OH and methyl viologen were 1 mM and 7 microM, respectively, at the pH and temperature optima (9.3 and 40 degrees C). The activity was oxygen-sensitive and was inhibited by sulfide and iron reagents. R. capsulatus E1F1 grew phototrophically, but not heterotrophically, with 1 mM NH(2)OH as nitrogen source, and up to 10 mM NH(2)OH was taken up by anaerobic resting cells. Ammonium was transiently accumulated in the media, and its assimilation was prevented by L-methionine-D,L-sulfoximine, a glutamine synthetase inhibitor. In addition, hydroxylamine- or nitrite-grown cells showed the higher hydroxylamine reductase activities. However, R. capsulatus B10S, a strain lacking the whole hcp-nas region, did not grow with 1 mM NH(2)OH. Also, E. coli cells overproducing HCP tolerate hydroxyl-amine better during anaerobic growth. These results suggest that HCP is involved in assimilation of NH(2)OH, a toxic product that could be formed during nitrate assimilation, probably in the nitrite reduction step.

  19. Photoabsorption and photoionization cross sections of NH3, PH3, H2S, C2H2, and C2H4 in the VUV region

    NASA Technical Reports Server (NTRS)

    Xia, T. J.; Chien, T. S.; Wu, C. Y. Robert; Judge, D. L.

    1991-01-01

    Using synchrotron radiation as a continuum light source, the photoabsorption and photoionization cross sections of NH3, PH3, H2S, C2H2, and C2H4 have been measured from their respective ionization thresholds to 1060 A. The vibrational constants associated with the nu(2) totally symmetric, out-of-plane bending vibration of the ground electronic state of PH3(+) have been obtained. The cross sections and quantum yields for producing neutral products through photoexcitation of these molecules in the given spectral regions have also been determined. In the present work, autoionization processes were found to be less important than dissociation and predissociation processes in NH3, PH3, and C2H4. Several experimental techniques have been employed in order to examine the various possible systematic errors critically.

  20. Cross-shelf exchanges between the Coral Sea and the Great Barrier Reef lagoon determined from a regional-scale numerical model

    NASA Astrophysics Data System (ADS)

    Schiller, Andreas; Herzfeld, Mike; Brinkman, Richard; Rizwi, Farhan; Andrewartha, John

    2015-10-01

    Analyses of the variability in a 3.5-year run of a hydrodynamic model developed for simulating the circulation of the Great Barrier Reef (GBR) are presented. Sea-surface temperature, salinity, currents and cross-shelf transports between the GBR lagoon and the deep ocean offshore are investigated and compare well to available observations. Water mass intrusions and flushing events are critical factors in determining the health of coral reef and continental shelf ecosystems. Results from tracer release experiments provide a synoptic view of the variability of residence times within the GBR and identify critical regions of shelf-ocean exchange. One such region of significant tracer contribution to the shelf is identified in the vicinity of the Pompey Reefs in an area characterised by increased frequency of upslope transported water. Another location of enhanced flux on to the shelf exists in the region bracketing Palm Passage, where the reef matrix is very open, and provides little obstacle to cross-shelf exchange. The Palm Passage location is the origin of a northwards plume of elevated concentration. The model circulation provides a robust and useful picture of the Great Barrier Reef, rendering the model suitable for providing input to biogeochemical and sediment models to simulate, at a broad scale, the ecosystem health, water quality, transport and fate of water and waterborne material, moving through catchments and into the GBR lagoon.

  1. Effectiveness of diagnostic screening tests in mass screening for COPD using a cooperative regional system in a region with heavy air pollution: a cross-sectional study

    PubMed Central

    Kotaki, Kenji; Ikeda, Hisao; Fukuda, Takeshi; Yuki, Fumiko; Hasuo, Kanehiro; Kawano, Yuhei; Kawasaki, Masayuki

    2017-01-01

    Objectives This study aimed to evaluate the effectiveness of a cooperative healthcare model for early detection and diagnosis of chronic obstructive pulmonary disease (COPD). Methods This was a cross-sectional observational study. We performed diagnosis of COPD at 4 public health centres in Ōmuta, Japan from March 2015 to March 2016, by adding screening for COPD at the time of routine medical evaluations. All patients aged over 40 years were eligible to participate. Among 397 eligible patients, 293 agreed to participate in the study. Results The estimated prevalence of COPD in Ōmuta was 10% among patients aged over 40 years and was 17% among smokers. Among those who were screened, over half of them had questionnaire scores over the cut-off of 17 points and decreased FEV1/FVC%, indicating COPD (p>0.05). 30 patients with suspected COPD were referred for further investigation at a local central hospital, but only 6 underwent further medical examinations. Conclusions The combination of a COPD questionnaire and medical examination is effective as a COPD screening tool. Future research should investigate behavioural interventions for smoking cessation that can be offered in a cooperative model, as well as for improving participation in COPD screening and for encouraging early presentation for treatment in those suspected of having COPD. PMID:28082365

  2. Disruption of the Globular Cluster Pal 5

    NASA Technical Reports Server (NTRS)

    Miller, R. H.; Smith, B. F.; Cuzzi, Jeffrey N. (Technical Monitor)

    1995-01-01

    Orbit calculations suggest that the sparse globular cluster, Pal 5, will pass within 7 kpc of the Galactic center the next time it crosses the plane, where it might be destroyed by tidal stresses. We study this problem, treating Pal 5 as a self-consistent dynamical system orbiting through an external potential that represents the Galaxy. The first part of the problem is to find suitable analytic approximations to the Galactic potential. They must be valid in all regions the cluster is likely to explore. Observed velocity and positional data for Pal 5 are used as initial conditions to determine the orbit. Methods we used for a different problem some 12 years ago have been adapted to this problem. Three experiments have been run, with M/L= 1, 3, and 10, for the cluster model. The cluster blew up shortly after passing through the Galactic plane (about 130 Myrs after the beginning of the run) with M/L=1. At M/L = 3 and 10 the cluster survived, although it got quite a kick in the fundamental mode on passing through the plane. But the fundamental mode oscillation died out in a couple of oscillation cycles at M/L=10. Pal 5 will probably be destroyed on its next crossing of the Galactic plane if M/L=1, but it can survive (albeit with fairly heavy damage) if NI/L=3. We haven't tried to trap the mass limits more closely than that. Pal 5 comes through pretty well unscathed at M/L=10. An interesting follow-up experiment would be to back the cluster up along its orbit to look at its previous passage through the Galactic plane, to see what kind of object it might have been at earlier times.

  3. LOW-FIDELITY COVARIANCES FOR NEUTRON CROSS SECTIONS ON 57 STRUCTURAL AND 31 HEAVY NUCLEI IN THE FAST REGION.

    SciTech Connect

    PIGNI,M.T.; HERMAN, M.; OBLOZINSKY, P.

    2008-03-01

    We produced a large set of neutron cross section covariances in the energy range of 5 keV-20 MeV. The present set of data on 57 structural materials and 31 heavy nuclei follows our earlier work on 219 fission product materials and completes our extensive contribution to the low-fidelity covariance project (307 materials). This project aims to provide initial, low-fidelity yet consistent estimates of covariance data for nuclear criticality safety applications. The evaluation methodology combines the nuclear reaction model code EMPIRE which calculates sensitivity to nuclear reaction model parameters, and the Bayesian code KALMAN that propagates uncertainties of the model parameters to cross sections. Taking into account the large scale of the project, only marginal reference to experimental data was made. The covariances were derived from the perturbation of several key model parameters selected by the sensitivity analysis. These parameters refer to the optical model potential, the level densities and the strength of the pre-equilibrium emission. This work represents the first attempt ever to generate nuclear data covariances on such a large scale.

  4. Improved GRACE regional mass balance estimates of the Greenland ice sheet cross-validated with the input-output method

    NASA Astrophysics Data System (ADS)

    Xu, Zheng; Schrama, Ernst J. O.; van der Wal, Wouter; van den Broeke, Michiel; Enderlin, Ellyn M.

    2016-04-01

    In this study, we use satellite gravimetry data from the Gravity Recovery and Climate Experiment (GRACE) to estimate regional mass change of the Greenland ice sheet (GrIS) and neighboring glaciated regions using a least squares inversion approach. We also consider results from the input-output method (IOM). The IOM quantifies the difference between the mass input and output of the GrIS by studying the surface mass balance (SMB) and the ice discharge (D). We use the Regional Atmospheric Climate Model version 2.3 (RACMO2.3) to model the SMB and derive the ice discharge from 12 years of high-precision ice velocity and thickness surveys. We use a simulation model to quantify and correct for GRACE approximation errors in mass change between different subregions of the GrIS, and investigate the reliability of pre-1990s ice discharge estimates, which are based on the modeled runoff. We find that the difference between the IOM and our improved GRACE mass change estimates is reduced in terms of the long-term mass change when using a reference discharge derived from runoff estimates in several subareas. In most regions our GRACE and IOM solutions are consistent with other studies, but differences remain in the northwestern GrIS. We validate the GRACE mass balance in that region by considering several different GIA models and mass change estimates derived from data obtained by the Ice, Cloud and land Elevation Satellite (ICESat). We conclude that the approximated mass balance between GRACE and IOM is consistent in most GrIS regions. The difference in the northwest is likely due to underestimated uncertainties in the IOM solutions.

  5. Local and regional components of aerosol in a heavily trafficked street canyon in central London derived from PMF and cluster analysis of single-particle ATOFMS spectra.

    PubMed

    Giorio, Chiara; Tapparo, Andrea; Dall'Osto, Manuel; Beddows, David C S; Esser-Gietl, Johanna K; Healy, Robert M; Harrison, Roy M

    2015-03-17

    Positive matrix factorization (PMF) has been applied to single particle ATOFMS spectra collected on a six lane heavily trafficked road in central London (Marylebone Road), which well represents an urban street canyon. PMF analysis successfully extracted 11 factors from mass spectra of about 700,000 particles as a complement to information on particle types (from K-means cluster analysis). The factors were associated with specific sources and represent the contribution of different traffic related components (i.e., lubricating oils, fresh elemental carbon, organonitrogen and aromatic compounds), secondary aerosol locally produced (i.e., nitrate, oxidized organic aerosol and oxidized organonitrogen compounds), urban background together with regional transport (aged elemental carbon and ammonium) and fresh sea spray. An important result from this study is the evidence that rapid chemical processes occur in the street canyon with production of secondary particles from road traffic emissions. These locally generated particles, together with aging processes, dramatically affected aerosol composition producing internally mixed particles. These processes may become important with stagnant air conditions and in countries where gasoline vehicles are predominant and need to be considered when quantifying the impact of traffic emissions.

  6. From superdeformation to extreme deformation and clusterization in the N ≈Z nuclei of the A ≈40 mass region

    NASA Astrophysics Data System (ADS)

    Ray, D.; Afanasjev, A. V.

    2016-07-01

    A systematic search for extremely deformed structures in the N ≈Z nuclei of the A ≈40 mass region has been performed for the first time in the framework of covariant density functional theory. At spin zero such structures are located at high excitation energies, which prevents their experimental observation. The rotation acts as a tool to bring these exotic shapes to the yrast line or its vicinity so that their observation could become possible with future generation of γ -tracking (or similar) detectors such as GRETA and AGATA. The major physical observables of such structures (such as transition quadrupole moments, as well as kinematic and dynamic moments of inertia), the underlying single-particle structure and the spins at which they become yrast or near yrast, are defined. The search for the fingerprints of clusterization and molecular structures is performed and the configurations with such features are discussed. The best candidates for observation of extremely deformed structures are identified. For several nuclei in this study (such as 36Ar), the addition of several spin units above the currently measured maximum spin of 16 ℏ will inevitably trigger the transition to hyper- and megadeformed nuclear shapes.

  7. Adaptive cluster detection

    NASA Astrophysics Data System (ADS)

    Friedenberg, David

    2010-10-01

    the rate of falsely detected active regions. Additionally we examine the more general field of clustering and develop a framework for clustering algorithms based around diffusion maps. Diffusion maps can be used to project high-dimensional data into a lower dimensional space while preserving much of the structure in the data. We demonstrate how diffusion maps can be used to solve clustering problems and examine the influence of tuning parameters on the results. We introduce two novel methods, the self-tuning diffusion map which replaces the global scaling parameter in the typical diffusion map framework with a local scaling parameter and an algorithm for automatically selecting tuning parameters based on a cross-validation style score called prediction strength. The methods are tested on several example datasets.

  8. Irrigation Effects on Hydro-Climatic Change: Basin-Wise Water Balance-Constrained Quantification and Cross-Regional Comparison

    NASA Astrophysics Data System (ADS)

    Asokan, Shilpa M.; Destouni, Georgia

    2014-05-01

    Hydro-climatic changes driven by human land and water use, including water use for irrigation, may be difficult to distinguish from the effects of global, natural and anthropogenic climate change. This paper quantifies and compares the hydro-climatic change effects of irrigation using a data-driven, basin-wise quantification approach in two different irrigated world regions: the Aral Sea drainage basin in Central Asia and the Indian Mahanadi River Basin draining into the Bay of Bengal. Results show that irrigation-driven changes in evapotranspiration and latent heat fluxes and associated temperature changes at the land surface may be greater in regions with small relative irrigation impacts on water availability in the landscape (here represented by the Mahanadi River Basin) than in regions with severe such impacts (here represented by the Aral region). Different perspectives on the continental part of Earth's hydrological cycle may thus imply different importance assessments of various drivers and impacts of hydro-climatic change. Regardless of perspective, however, actual basin-wise water balance constraints should be accounted to realistically understand and accurately quantify continental water change.

  9. Effects of photoaging information and UV photo on sun protection intentions and behaviours: a cross-regional comparison.

    PubMed

    Mahler, Heike I M; Kulik, James A; Gerrard, Meg; Gibbons, Frederick X

    2013-01-01

    There is limited empirical evidence regarding differences in sun protection practices in different regions of the USA. This study examined whether there are regional differences in the efficacy of exposure to UV photographs and photoaging information (e.g. wrinkles and age spots) for increasing sun protection behaviours. Students attending a public university in either the Midwestern (Iowa) or Southwestern (Southern California) US reported baseline sun exposure and protection practices and were then randomly assigned to either receive information about photoaging, have a UV photo taken, both receive photoaging information and have a UV photo taken, or to receive neither intervention. Sun protection intentions were assessed immediately after the interventions, and both self-reported sun protection behaviours and an objective assessment (via spectrophotometry) of skin colour change were measured at the end of summer and one year following the interventions. The results showed a pervasive pattern of more risky UV exposure and less sun protection use at the Iowa site than at the Southern California site both prior to and following the interventions. Both interventions increased future sun protection intentions regardless of region. However, the intervention effects on skin colour and UV exposure differed across region, with generally more reliable effects at the Iowa site.

  10. Presented by REL Pacific at McREL: A Summary of Cross-Regional Educational Laboratory Studies. Research Digest

    ERIC Educational Resources Information Center

    Regional Educational Laboratory Pacific, 2013

    2013-01-01

    REL Pacific at McREL, 1 of 10 Regional Educational Laboratories (RELs) funded by the Institute of Education Sciences (IES), serves educators in American Samoa, the Commonwealth of the Northern Mariana Islands, the Federated States of Micronesia (Chuuk, Kosrae, Pohnpei, and Yap), Guam, Hawai'i, the Republic of the Marshall Islands, and the Republic…

  11. Cross-species complementation of the indispensable Escherichia coli era gene highlights amino acid regions essential for activity.

    PubMed Central

    Pillutla, R C; Sharer, J D; Gulati, P S; Wu, E; Yamashita, Y; Lerner, C G; Inouye, M; March, P E

    1995-01-01

    Era is an essential GTP binding protein in Escherichia coli. Two homologs of this protein, Sgp from Streptococcus mutans and Era from Coxiella burnetii, can substitute for the essential function of Era in E. coli. Site-specific and randomly generated Era mutants which may indicate regions of the protein that are of functional importance are described. PMID:7721709

  12. Ratios of 15N/12C and 4He/12C inclusive electroproduction cross sections in the nucleon resonance region

    SciTech Connect

    Peter Bosted; Robert Fersch

    2007-12-14

    The ratio of inclusive electron scattering cross sections for 15N/12C was determined in the kinematic range 0.8<2 GeV and 0.2<1 GeV2 using 2.285 GeV electrons and the CLAS detector at Jefferson Lab. The ratio exhibits only slight resonance structure, as predicted by a phenomenological model, and also by quark-hadron duality. Within the super-scaling quasi-elastic model, slight evidence is found for a 1 MeV lower effective nucleon binding energy in 15N than in 12C. Ratios of 4He/12C using 1.6 to 2.5 GeV electrons are in good agreement with the phenomenological model.

  13. Cross-border radon index map 1:100 000 Lausitz - Jizera - Karkonosze - Region (northern part of the Bohemian Massif).

    PubMed

    Barnet, Ivan; Pacherová, Petra; Preusse, Werner; Stec, Bartosz

    2010-10-01

    The first cross-border map describing the radon (Rn) risk from bedrock was assembled in the northern part of the Bohemian Massif at a scale 1:100 000. The map covers the area of Lausitz (Germany), Karkonosze (Czech Republic and Poland) and Jizera (Czech Republic). The map is based on 818 measurements of soil gas Rn in rock types of Precambrian to Mesozoic age with variable geology. Geographic information system (GIS) processing enabled a good coincidence of soil gas Rn concentrations between data from all three countries in lithologically adjacent rock types as well as the direct correlation to georeferenced indoor Rn values, which was tested using the Czech indoor Rn data. The method of data processing can contribute to assembling the European Geogenic Radon Map.

  14. A cross-sectional investigation of regional patterns of diet and cardio-metabolic risk in India

    PubMed Central

    2011-01-01

    Background The role of diet in India's rapidly progressing chronic disease epidemic is unclear; moreover, diet may vary considerably across North-South regions. Methods The India Health Study was a multicenter study of men and women aged 35-69, who provided diet, lifestyle, and medical histories, as well as blood pressure, fasting blood, urine, and anthropometric measurements. In each region (Delhi, n = 824; Mumbai, n = 743; Trivandrum, n = 2,247), we identified two dietary patterns with factor analysis. In multiple logistic regression models adjusted for age, gender, education, income, marital status, religion, physical activity, tobacco, alcohol, and total energy intake, we investigated associations between regional dietary patterns and abdominal adiposity, hypertension, diabetes, and dyslipidemia. Results Across the regions, more than 80% of the participants met the criteria for abdominal adiposity and 10 to 28% of participants were considered diabetic. In Delhi, the "fruit and dairy" dietary pattern was positively associated with abdominal adiposity [highest versus lowest tertile, multivariate-adjusted OR and 95% CI: 2.32 (1.03-5.23); Ptrend = 0.008] and hypertension [2.20 (1.47-3.31); Ptrend < 0.0001]. In Trivandrum, the "pulses and rice" pattern was inversely related to diabetes [0.70 (0.51-0.95); Ptrend = 0.03] and the "snacks and sweets" pattern was positively associated with abdominal adiposity [2.05 (1.34-3.14); Ptrend = 0.03]. In Mumbai, the "fruit and vegetable" pattern was inversely associated with hypertension [0.63 (0.40-0.99); Ptrend = 0.05] and the "snack and meat" pattern appeared to be positively associated with abdominal adiposity. Conclusions Cardio-metabolic risk factors were highly prevalent in this population. Across all regions, we found little evidence of a Westernized diet; however, dietary patterns characterized by animal products, fried snacks, or sweets appeared to be positively associated with abdominal adiposity. Conversely, more

  15. Time development of high-altitude auroral acceleration region plasma, potentials, and field-aligned current systems observed by Cluster during a substorm

    NASA Astrophysics Data System (ADS)

    Hull, A. J.; Chaston, C. C.; Fillingim, M. O.; Mozer, F.; Frey, H. U.

    2013-12-01

    The auroral acceleration region is an integral link in the chain of events that transpire during substorms, and the currents, plasma and electric fields undergo significant changes driven by complex dynamical processes deep in the magnetotail. These auroral acceleration processes in turn accelerate and heat the plasma that ultimately leads to some of the most intense global substorm auroral displays. The complex interplay between field-aligned current system formation, the development of parallel electric fields, and resultant changes in the plasma constituents that occur during substorms within or just above the auroral acceleration zone remain unclear. We present Cluster multi-point observations within the high-altitude acceleration region (> 3 Re altitude) at key instances during the development of a substorm. Of particular emphasis is on the time-development of the plasma, potentials and currents that occur therein with the aim of ascertaining high-altitude drivers of substorm active auroral acceleration processes and auroral emission consequences. Preliminary results show that the initial onset is dominated by Alfvenic activity as evidenced by the sudden occurrence of relatively intense, short-spatial scale Alfvenic currents and attendant energy dispersed, counterstreaming electrons poleward of the growth-phase arc. The Alfvenic currents are locally planar structures with characteristic thicknesses on the order of a few tens of kilometers. In subsequent passages by the other spacecraft, the plasma sheet region became hotter and thicker via the injection of new hot, dense plasma of magnetospheric origins poleward of the pre-existing growth phase arc. In association with the heating and/or thickening of the plasma sheet, the currents appeared to broaden to larger scales as Alfven dominated activity gave way to either inverted-V dominated or mixed inverted-V and Alfvenic behavior depending on location. The transition from Alfven dominated to inverted-V dominated

  16. Cross - Scale Intercomparison of Climate Change Impacts Simulated by Regional and Global Hydrological Models in Eleven Large River Basins

    NASA Technical Reports Server (NTRS)

    Hattermann, F. F.; Krysanova, V.; Gosling, S. N.; Dankers, R.; Daggupati, P.; Donnelly, C.; Florke, M.; Huang, S.; Motovilov, Y.; Buda, S.; Wada, Y.

    2017-01-01

    Ideally, the results from models operating at different scales should agree in trend direction and magnitude of impacts under climate change. However, this implies that the sensitivity to climate variability and climate change is comparable for impact models designed for either scale. In this study, we compare hydrological changes simulated by 9 global and 9 regional hydrological models (HM) for 11 large river basins in all continents under reference and scenario conditions. The foci are on model validation runs, sensitivity of annual discharge to climate variability in the reference period, and sensitivity of the long-term average monthly seasonal dynamics to climate change. One major result is that the global models, mostly not calibrated against observations, often show a considerable bias in mean monthly discharge, whereas regional models show a better reproduction of reference conditions. However, the sensitivity of the two HM ensembles to climate variability is in general similar. The simulated climate change impacts in terms of long-term average monthly dynamics evaluated for HM ensemble medians and spreads show that the medians are to a certain extent comparable in some cases, but have distinct differences in other cases, and the spreads related to global models are mostly notably larger. Summarizing, this implies that global HMs are useful tools when looking at large-scale impacts of climate change and variability. Whenever impacts for a specific river basin or region are of interest, e.g. for complex water management applications, the regional-scale models calibrated and validated against observed discharge should be used.

  17. Terrestrial ecosystems of the Osa-Golfito region: one component of an integrative cross-disciplinary initiative for sustainability

    NASA Astrophysics Data System (ADS)

    Broadbent, E. N.; Dirzo, R.; Morales Barquero, L.

    2012-12-01

    Sustainability science seeks to develop approaches incorporating simultaneous human and environmental well-being. The Osa-Golfito Initiative (InOGo), as described in the previous presentation by Dr. Hunt et al. in this session, represents a cutting edge project seeking to develop both a fundamental framework for linking interdisciplinary components to address this objective with the creation of an applied approach for a sustainable future in this area of exceptional cultural and environmental diversity. In this presentation we describe the terrestrial ecosystems component of InOGo. This component incorporates four primary research approaches: (a) an extensive literature review; (b) spatial and non-spatial data aggregation; (c) change analysis via remote sensing; and (d) a questionnaire and participatory mapping survey with relevant experts. Integrating these approaches we seek to: (a) establish a detailed baseline understanding of the terrestrial ecosystems and their spatial distribution in the study region; (b) quantify temporal changes in their extent, connectivity, and ecosystem services; (c) identify the principal conservation priorities and threats in the region; and (d) isolate specific actions to address identified threats. We highlight both the overall approach developed for this component, which is broadly applicable throughout similar tropical regions, as well as results specific to the initiative.;

  18. Assessing a cross-border logistics policy using a performance measurement system framework: the case of Hong Kong and the Pearl River Delta region

    NASA Astrophysics Data System (ADS)

    Wong, David W. C.; Choy, K. L.; Chow, Harry K. H.; Lin, Canhong

    2014-06-01

    For the most rapidly growing economic entity in the world, China, a new logistics operation called the indirect cross-border supply chain model has recently emerged. The primary idea of this model is to reduce logistics costs by storing goods at a bonded warehouse with low storage cost in certain Chinese regions, such as the Pearl River Delta (PRD). This research proposes a performance measurement system (PMS) framework to assess the direct and indirect cross-border supply chain models. The PMS covers four categories including cost, time, quality and flexibility in the assessment of the performance of direct and indirect models. Furthermore, a survey was conducted to investigate the logistics performance of third party logistics (3PLs) at the PRD regions, including Guangzhou, Shenzhen and Hong Kong. The significance of the proposed PMS framework allows 3PLs accurately pinpoint the weakness and strengths of it current operations policy at four major performance measurement categories. Hence, this helps 3PLs further enhance the competitiveness and operations efficiency through better resources allocation at the area of warehousing and transportation.

  19. Analysis of a sequence region of 5S RNA from E. coli cross-linked in situ to the ribosomal protein L25.

    PubMed Central

    Szymkowiak, C; Wagner, R

    1985-01-01

    70S ribosomes from E. coli were chemically cross-linked under conditions of in vitro protein biosynthesis. The ribosomal RNAs were extracted from reacted ribosomes and separated on sucrose gradients. The 5S RNA was shown to contain the ribosomal protein L25 covalently bound. After total RNase T1 hydrolysis of the covalent RNA-protein complex several high molecular weight RNA fragments were obtained and identified by sequencing. One fragment, sequence region U103 to U120, was shown to be directly linked to the protein first by protein specific staining of the particular fragment and second by phosphor cellulose chromatography of the covalent RNA-protein complex. The other two fragments, U89 to G106 and A34 to G51, could not be shown to be directly linked to L25 but were only formed under cross-linking conditions. While the fragment U89 to G106 may be protected from RNase T1 digestion because of a strong interaction with the covalent RNA-protein complex, the formation of the fragment A34 to G51 is very likely the result of a double monovalent modification of two neighbouring guanosines in the 5S RNA. The RNA sequences U103 to U120 established to be in direct contact to the protein L25 within the ribosome falls into the sequence region previously proposed as L25 binding site from studies with isolated 5S RNA-protein complexes. Images PMID:3892485

  20. ST5 Observations of the Imbalance of Region 1 and 2 Field-Aligned Currents and Its Implication to the Cross-Polar Cap Pedersen Currents

    NASA Technical Reports Server (NTRS)

    Le, Guan; Slavin, J. A.; Strangeway, Robert

    2011-01-01

    In this study, we use the in-situ magnetic field observations from Space Technology 5 mission to quantify the imbalance of Region 1 (R1) and Region 2 (R2) currents. During the three-month duration of the ST5 mission, geomagnetic conditions range from quiet to moderately active. We find that the R1 current intensity is consistently stronger than the R2 current intensity both for the dawnside and the duskside large-scale field-aligned current system. The net currents flowing into (out of) the ionosphere in the dawnside (duskside) are in the order of 5% of the total R1 currents. We also find that the net currents flowing into or out of the ionosphere are controlled by the solar wind-magnetosphere interaction in the same way as the field-aligned currents themselves are. Since the net currents due to the imbalance of the R1 and R2 currents require that their closure currents flow across the polar cap from dawn to dusk as Pedersen currents, our results indicate that the total amount of the cross-polar cap Pedersen currents is in the order of 0.1 MA. This study, although with a very limited dataset, is one of the first attempts to quantify the cross-polar cap Pedersen currents. Given the importance of the Joule heating due to Pedersen currents to the high-latitude ionospheric electrodynamics, quantifying the cross-polar cap Pedersen currents and associated Joule heating is needed for developing models of the magnetosphere-ionosphere coupling.

  1. A cross-sectional study of age-related changes in plantar pressure distribution between 4 and 7 years: a comparison of regional and pixel-level analyses.

    PubMed

    Phethean, Jill; Pataky, Todd C; Nester, Christopher J; Findlow, Andrew H

    2014-01-01

    Quantifying morphological and functional development in children's feet, and thereby establishing development norms is difficult. In addition to practical challenges of experimentation on children, measurement equipment like plantar pressure (PP) platforms are almost exclusively geared towards adult-sized feet. These PP quantification problems may be exacerbated by typical regional data analysis techniques, which further reduce spatial resolution. The goal of this study was to quantify PP distributions in developing children, and also to compare the results obtained from typical (regional) techniques with those obtained from a higher-resolution (pixel-level) technique. Ninety-eight children between four and seven years of age were assessed in a cross-sectional design. Maximum PP distributions were collected for each child, and these pressures were linearly regressed against age. Present results agree with previous investigations in that maximum pressures and maximum pressure changes occurred in the forefoot. However, results from the present pixel-level technique suggest that these changes are limited to the central metatarsals, and that regional methods can suggest significance where none exists in the actual raw (pixel-level) data, due to signal aliasing and, in particular, to conflation of regional boundaries. We postulate that increased central metatarsal pressures are reflective of the coupling between generalised joint laxity decreases and relatively increasingly inclined central metatarsal bones with age.

  2. Star Clusters within FIRE

    NASA Astrophysics Data System (ADS)

    Perez, Adrianna; Moreno, Jorge; Naiman, Jill; Ramirez-Ruiz, Enrico; Hopkins, Philip F.

    2017-01-01

    In this work, we analyze the environments surrounding star clusters of simulated merging galaxies. Our framework employs Feedback In Realistic Environments (FIRE) model (Hopkins et al., 2014). The FIRE project is a high resolution cosmological simulation that resolves star forming regions and incorporates stellar feedback in a physically realistic way. The project focuses on analyzing the properties of the star clusters formed in merging galaxies. The locations of these star clusters are identified with astrodendro.py, a publicly available dendrogram algorithm. Once star cluster properties are extracted, they will be used to create a sub-grid (smaller than the resolution scale of FIRE) of gas confinement in these clusters. Then, we can examine how the star clusters interact with these available gas reservoirs (either by accreting this mass or blowing it out via feedback), which will determine many properties of the cluster (star formation history, compact object accretion, etc). These simulations will further our understanding of star formation within stellar clusters during galaxy evolution. In the future, we aim to enhance sub-grid prescriptions for feedback specific to processes within star clusters; such as, interaction with stellar winds and gas accretion onto black holes and neutron stars.

  3. A cross-sectional study of Taenia solium in a multiple taeniid-endemic region reveals competition may be protective.

    PubMed

    Conlan, James V; Vongxay, Khamphouth; Khamlome, Boualam; Dorny, Pierre; Sripa, Banchob; Elliot, Aileen; Blacksell, Stuart D; Fenwick, Stanley; Thompson, R C Andrew

    2012-08-01

    We conducted cross-sectional surveys for taeniasis and cysticercosis in humans, pigs, and dogs in four northern provinces of Laos. Human cysticercosis and taeniasis prevalence was 2.2% (95% confidence interval [CI] = 1.4-3.0%) and 8.4% (95% CI = 6.9-9.9%), respectively. Eating uncooked beef, being male, province of residence, age, and ethnicity were significant risk factors for taeniasis and only province of residence was a significant risk factor for cystiercosis. Thirty-five human tapeworms were recovered during the survey and 33 (94.3%) and 2 (5.7%) were identified as Taenia saginata and T. solium, respectively. Maximum-likelihood adjusted prevalence of T. solium and T. hydatigena in pigs was 4.2% (95% CI = 0.5-7.9%) and 55.9% (95% CI = 47.5-64.3%), respectively, and T. hydatigena taeniasis in dogs was 4.8% (95% CI = 0.0-11.3%). Taenia hydatigena and T. saginata were the most prevalent taeniids in the respective pig and human populations and together may suppress T. solium transmission.

  4. Water, Sanitation, and Hygiene in Schools in Low Socio-Economic Regions in Nicaragua: A Cross-Sectional Survey

    PubMed Central

    Jordanova, Tania; Cronk, Ryan; Obando, Wanda; Medina, Octavio Zeledon; Kinoshita, Rinko; Bartram, Jamie

    2015-01-01

    Water, sanitation, and hygiene (WaSH) in schools contributes to better health and educational outcomes among school-aged children. In 2012, UNICEF Nicaragua and partners conducted a cross-sectional survey of WaSH in 526 schools in 12 low socio-economic status municipalities in Nicaragua. The survey gathered information on: school characteristics; teacher and community participation; water and sanitation infrastructure; and hygiene education and habits. Survey results were analyzed for associations between variables. WaSH coverage was significantly higher in urban than rural areas. Presence of drinking water infrastructure (43%) was lower than sanitation infrastructure (64%). Eighty-one percent of schools had no hand washing stations and 74% of schools lacked soap. Sanitation facilities were not in use at 28% of schools with sanitation infrastructure and 26% of schools with water infrastructure had non-functional systems. Only 8% of schools had budgets to purchase toilet-cleaning supplies and 75% obtained supplies from students’ families. This study generates transferable WaSH sector learnings and new insights from monitoring data. Results can be used by donors, service providers, and policy makers to better target resources in Nicaraguan schools. PMID:26035665

  5. Soil transmitted helminthiasis in indigenous groups. A community cross sectional study in the Amazonian southern border region of Ecuador

    PubMed Central

    Romero-Sandoval, Natalia; Ortiz-Rico, Claudia; Sánchez-Pérez, Héctor Javier; Valdivieso, Daniel; Sandoval, Carlos; Pástor, Jacob; Martín, Miguel

    2017-01-01

    Background Rural communities in the Amazonian southern border of Ecuador have benefited from governmental social programmes over the past 9 years, which have addressed, among other things, diseases associated with poverty, such as soil transmitted helminth infections. The aim of this study was to explore the prevalence of geohelminth infection and several factors associated with it in these communities. Methods This was a cross sectional study in two indigenous communities of the Amazonian southern border of Ecuador. The data were analysed at both the household and individual levels. Results At the individual level, the prevalence of geohelminth infection reached 46.9% (95% CI 39.5% to 54.2%), with no differences in terms of gender, age, temporary migration movements or previous chemoprophylaxis. In 72.9% of households, one or more members were infected. Receiving subsidies and overcrowding were associated with the presence of helminths. Conclusions The prevalence of geohelminth infection was high. Our study suggests that it is necessary to conduct studies focusing on communities, and not simply on captive groups, such as schoolchildren, with the object of proposing more suitable and effective strategies to control this problem. PMID:28292765

  6. A Cross-Sectional Study of Taenia solium in a Multiple Taeniid-Endemic Region Reveals Competition May be Protective

    PubMed Central

    Conlan, James V.; Vongxay, Khamphouth; Khamlome, Boualam; Dorny, Pierre; Sripa, Banchob; Elliot, Aileen; Blacksell, Stuart D.; Fenwick, Stanley; Thompson, R. C. Andrew

    2012-01-01

    We conducted cross-sectional surveys for taeniasis and cysticercosis in humans, pigs, and dogs in four northern provinces of Laos. Human cysticercosis and taeniasis prevalence was 2.2% (95% confidence interval [CI] = 1.4–3.0%) and 8.4% (95% CI = 6.9–9.9%), respectively. Eating uncooked beef, being male, province of residence, age, and ethnicity were significant risk factors for taeniasis and only province of residence was a significant risk factor for cystiercosis. Thirty-five human tapeworms were recovered during the survey and 33 (94.3%) and 2 (5.7%) were identified as Taenia saginata and T. solium, respectively. Maximum-likelihood adjusted prevalence of T. solium and T. hydatigena in pigs was 4.2% (95% CI = 0.5–7.9%) and 55.9% (95% CI = 47.5–64.3%), respectively, and T. hydatigena taeniasis in dogs was 4.8% (95% CI = 0.0–11.3%). Taenia hydatigena and T. saginata were the most prevalent taeniids in the respective pig and human populations and together may suppress T. solium transmission. PMID:22855759

  7. Hydrochemistry of surface water and groundwater in the shale bedrock, Cross River Basin and Niger Delta Region, Nigeria

    NASA Astrophysics Data System (ADS)

    Nganje, T. N.; Hursthouse, A. S.; Edet, Aniekan; Stirling, D.; Adamu, C. I.

    2015-07-01

    Water chemistry in the shale bedrock of the Cretaceous-Tertiary of the Cross River and Niger Delta hydrological basins has been investigated using major ions. To carry out a characterization of the water bearing units, 30 and 16 representatives surface and groundwater samples were collected. The evolution of the water is characterized by enhanced content of sodium, calcium and sulphate as a result of leaching of shale rock. The spatial changes in groundwater quality of the area shows an anomalous concentrations of ions in the central parts, while lower values characterize the eastern part of the basin covering Ogoja, Ikom and Odukpani areas. The values of total dissolved solids (TDS) and ions increases down gradient in the direction of groundwater flow. The dissolution of halite and gypsum explains part of the contained Na+, Ca2+, Cl- and SO4 2-, but other processes such as ion exchange, silicate weathering and pyrite oxidation also contribute to water composition. The assessment with contamination indicators such as TDS, hardness, chloride, nitrate and sulphate indicates that the water in area is suitable for human consumption in some locations. Modelling using MINTEQA2 program shows that the water from all the shale water bearing units are under saturated with respect to gypsum.

  8. Coping behavior and risk and resilience stress factors in French regional emergency medicine unit workers: a cross-sectional survey

    PubMed Central

    Lala, AI; Sturzu, LM; Picard, JP; Druot, F; Grama, F; Bobirnac, G

    2016-01-01

    The Emergency Department (ED) has the highest workload in a hospital, offering care to patients in their most acute state of illness, as well as comforting their families and tending to stressful situations of the physical and psychological areal. Method. A cross-sectional survey of 366 Emergency Unit staff members including medical doctors, medical residents, medical nurses and ward aids, was undergone. Study participants came from four periphery hospitals in the Moselle Department of Eastern France with similar workforce and daily patient loads statistics. The instruments used were the Perceived Stress Scale PSS-10 and the Brief COPE questionnaire. Conclusions. Perceived work overload and overall stress is strongly related to work hours and tend to have a stronger influence on doctors than on the nursing staff. Substance use is a common coping method for medical interns, consistent with prior research. The regular assessment of the ED staff perception of stress and stress related factors is essential to support organizational decisions in order to promote a better work environment and better patient care. PMID:27928439

  9. Human Puumala and Dobrava Hantavirus Infections in the Black Sea Region of Turkey: A Cross-Sectional Study

    PubMed Central

    Kalaycioglu, Handan; Uyar, Yavuz; Sevindi, Demet Furkan; Turkyilmaz, Bedia; Çakir, Vedat; Cindemir, Cengiz; Unal, Belgin; Yağçi-Çağlayik, Dilek; Korukluoglu, Gulay; Ertek, Mustafa; Heyman, Paul; Lundkvist, Åke

    2013-01-01

    Abstract This study was carried out to better understand the epidemiology of hantaviruses in a province of Turkey (Giresun) where human hantavirus disease has recently been detected. In this cross-sectional study, a total of 626 blood samples from healthy people aged 15 and 84 years old were collected both in urban and rural areas in 2009. The sera were tested by enzyme-linked immunosorbent assay (ELISA), immunoblotting assay, and the focus reduction neutralization test (FRNT). We screened the samples by an ELISA and found that 65/626 samples reacted positively for the presence of hantavirus-reactive immunoglobulin G (IgG). Twenty of the 65 ELISA-positive samples could be confirmed by an immunobloting assay, and the overall seroprevalence was thereby calculated to 3.2% (20/626). The seroprevalence of the people living in wood areas or adobe houses 9/17 (52.9%) was significantly higher than among people living in concrete houses 10/47 (21.3%) (p=0.014). Finally, 3 of the 20 immunoblot-positive sera were confirmed as specific for the Puumala hantavirus serotype by FRNT, 1 serum was confirmed as Dobrava virus-specific, whereas 1 serum was found to be equally reactive to Dobrava and Saaremaa viruses. We will now focus on further investigations of the ecology and epidemiology of hantaviruses in humans and their carrier animals in Turkey, studies that have already been started and will be further intensified. PMID:23289396

  10. Water, sanitation, and hygiene in schools in low socio-economic regions in Nicaragua: a cross-sectional survey.

    PubMed

    Jordanova, Tania; Cronk, Ryan; Obando, Wanda; Medina, Octavio Zeledon; Kinoshita, Rinko; Bartram, Jamie

    2015-05-29

    Water, sanitation, and hygiene (WaSH) in schools contributes to better health and educational outcomes among school-aged children. In 2012, UNICEF Nicaragua and partners conducted a cross-sectional survey of WaSH in 526 schools in 12 low socio-economic status municipalities in Nicaragua. The survey gathered information on: school characteristics; teacher and community participation; water and sanitation infrastructure; and hygiene education and habits. Survey results were analyzed for associations between variables. WaSH coverage was significantly higher in urban than rural areas. Presence of drinking water infrastructure (43%) was lower than sanitation infrastructure (64%). Eighty-one percent of schools had no hand washing stations and 74% of schools lacked soap. Sanitation facilities were not in use at 28% of schools with sanitation infrastructure and 26% of schools with water infrastructure had non-functional systems. Only 8% of schools had budgets to purchase toilet-cleaning supplies and 75% obtained supplies from students' families. This study generates transferable WaSH sector learnings and new insights from monitoring data. Results can be used by donors, service providers, and policy makers to better target resources in Nicaraguan schools.

  11. The mechanism of mammalian gene replacement is consistent with the formation of long regions of heteroduplex DNA associated with two crossing-over events.

    PubMed

    Li, J; Read, L R; Baker, M D

    2001-01-01

    In this study, the mechanism of mammalian gene replacement was investigated. The system is based on detecting homologous recombination between transferred vector DNA and the haploid, chromosomal immunoglobulin mu-delta region in a murine hybridoma cell line. The backbone of the gene replacement vector (pCmuCdeltapal) consists of pSV2neo sequences bounded on one side by homology to the mu gene constant (Cmu) region and on the other side by homology to the delta gene constant (Cdelta) region. The Cmu and Cdelta flanking arms of homology were marked by insertions of an identical 30-bp palindrome which frequently escapes mismatch repair when in heteroduplex DNA (hDNA). As a result, intermediates bearing unrepaired hDNA generate mixed (sectored) recombinants following DNA replication and cell division. To monitor the presence and position of sectored sites and, hence, hDNA formation during the recombination process, the palindrome contained a unique NotI site that replaced an endogenous restriction enzyme site at each marker position in the vector-borne Cmu and Cdelta regions. Gene replacement was studied under conditions which permitted the efficient recovery of the product(s) of individual recombination events. Analysis of marker segregation patterns in independent recombinants revealed that extensive hDNA was formed within the Cmu and Cdelta regions. In several recombinants, palindrome markers in the Cmu and Cdelta regions resided on opposite DNA strands (trans configuration). These results are consistent with the mammalian gene replacement reaction involving two crossing-over events in homologous flanking DNA.

  12. A cross-sectional study of clinical management, and provision of health services and their utilisation, by patients with Parkinson's disease in urban and regional Victoria.

    PubMed

    Lubomski, Michal; Rushworth, R Louise; Lee, Will; Bertram, Kelly; Williams, David R

    2013-01-01

    Our objective was to evaluate and compare clinical management, utilisation of health services and quality of life (QoL) in patients with Parkinson's disease (PD) attending clinics in urban and regional Victoria. A cross-sectional survey was conducted on 210 patients with PD attending specialist neurological clinics in a regional area (Ballarat) (n=97), and an urban area (Melbourne) (n=113), Victoria. Demographic characteristics of patients with PD, QoL, patterns of disease and management and utilisation of medical and allied health services were analysed. Compared to patients with PD from urban clinics, patients in the regional clinic were significantly older and were diagnosed at a later age with a shorter duration of treatment (all p<0.05). Despite no significant difference in disease severity (measured by Unified Parkinson's Disease Rating Scale scores) between the groups, patients in the urban clinic reported a lower QoL (p=0.003). Patients in the regional clinic were more satisfied with their treatment, despite seeing their medical specialist less frequently (p<0.001) and having a higher rate of early misdiagnosis (p=0.015). Patients from regional clinics reported a poorer understanding of their illness than patients in the urban clinic (p=0.049). Half of all respondents were interested in using telemedicine services. Two-thirds (71%) of all patients used allied health services, with patients in the urban clinic utilising more and desiring greater access to these services (p<0.05). In conclusion, we found significant differences in the presentation, management and use of health services between patients accessing regional and urban PD clinics in Victoria. Telemedicine may be an effective, and even desirable, method for facilitating improved diagnosis and referral for appropriate therapies.

  13. Atomic form factors and photoelectric absorption cross-sections near absorption edges in the soft X-ray region

    SciTech Connect

    Chantler, C.

    2006-11-09

    Reliable knowledge of the complex X-ray form factor [Re(f) and Im(f)] and the photoelectric attenuation coefficient ({delta}{sub PE}) is required for crystallography, medical diagnosis, radiation safety and XAFS studies. Key discrepancies in earlier theoretical work are due to the smoothing of edge structure, the use of non-relativistic wave functions, and the lack of appropriate convergence of wave functions. These discrepancies lead to significant corrections for most comprehensive (i.e. all-Z) tabulations. This work has led to a major comprehensive database tabulation [Chantler, C. T. (2000). J. Phys. Chem. Ref. Data, 29, 597-1048] which serves as a sequel and companion to earlier relativistic Dirac-Fock computations [Chantler, C. T. (1995). J. Phys. Chem. Ref. Data, 24, 71-643]. The paper finds that earlier work needs improvement in the near-edge region for soft X-ray energies, and derives new theoretical results of substantially higher accuracy in near-edge soft X-ray regions. Fine grids near edges are tabulated demonstrating the current comparison with alternate theory and with available experimental data. The best experimental data and the observed experimental structure as a function of energy are strong indicators of the validity of the current approach. New developments in experimental measurement hold great promise in making critical comparisons with theory in the near future.

  14. Atomic form factors and photoelectric absorption cross-sections near absorption edges in the soft X-ray region

    SciTech Connect

    Chantler, C.T.

    2003-01-24

    Reliable knowledge of the complex X-ray form factor [Re(f) and Im(f)] and the photoelectric attenuation coefficient ({sigma}PE) is required for crystallography, medical diagnosis, radiation safety and XAFS studies. Key discrepancies in earlier theoretical work are due to the smoothing of edge structure, the use of non-relativistic wave functions, and the lack of appropriate convergence of wave functions. These discrepancies lead to significant corrections for most comprehensive (i.e. all-Z) tabulations. This work has led to a major comprehensive database tabulation [Chantler, C. T. (2000). J. Phys. Chem. Ref. Data, 29, 597-1048] which serves as a sequel and companion to earlier relativistic Dirac-Fock computations [Chantler, C. T. (1995). J. Phys. Chem. Ref. Data, 24, 71-643]. The paper finds that earlier work needs improvement in the near-edge region for soft X-ray energies, and derives new theoretical results of substantially higher accuracy in near-edge soft X-ray regions. Fine grids near edges are tabulated demonstrating the current comparison with alternate theory and with available experimental data. The best experimental data and the observed experimental structure as a function of energy are strong indicators of the validity of the current approach. New developments in experimental measurement hold great promise in making critical comparisons with theory in the near future. This work forms the latest component of the FFAST NIST database [http://physics.nist.gov/PhysRefData/FFast02/Text/cover.html].

  15. Classical dynamics and localization of resonances in the high-energy region of the hydrogen atom in crossed fields.

    PubMed

    Schweiner, Frank; Main, Jörg; Cartarius, Holger; Wunner, Günter

    2015-01-01

    When superimposing the potentials of external fields on the Coulomb potential of the hydrogen atom, a saddle point (called the Stark saddle point) appears. For energies slightly above the saddle point energy, one can find classical orbits that are located in the vicinity of this point. We follow those so-called quasi-Penning orbits to high energies and field strengths, observing structural changes and uncovering their bifurcation behavior. By plotting the stability behavior of those orbits against energy and field strength, the appearance of a stability apex is reported. A cusp bifurcation, located in the vicinity of the apex, will be investigated in detail. In this cusp bifurcation, another orbit of similar shape is found. This orbit becomes completely stable in the observed region of positive energy, i.e., in a region of parameter space, where the Kepler-like orbits located around the nucleus are already unstable. By quantum mechanically exact calculations, we prove the existence of signatures in quantum spectra belonging to those orbits. Husimi distributions are used to compare quantum-Poincaré sections with the extension of the classical torus structure around the orbits. Since periodic orbit theory predicts that each classical periodic orbit contributes an oscillating term to photoabsorption spectra, we finally give an estimation for future experiments, which could verify the existence of the stable orbits.

  16. Alkali Metal Cluster Theory.

    NASA Astrophysics Data System (ADS)

    Chen, Jian

    Available from UMI in association with The British Library. Requires signed TDF. In this thesis, we apply the tight-binding Hubbard model to alkali metal clusters with Hartree-Fock self-consistent methods and perturbation methods for the numerical calculations. We have studied the relation between the equilibrium structures and the range of the hopping matrix elements in the Hubbard Hamiltonian. The results show that the structures are not sensitive to the interaction range but are determined by the number of valence electrons each atom has. Inertia tensors are used to analyse the symmetries of the clusters. The principal axes of the clusters are determined and they are the axes of rotational symmetries of clusters if the clusters have any. The eigenvalues of inertia tensors which are the indication of the deformation of clusters are compared between our model and the ellipsoidal jellium model. The agreement is good for large clusters. At a finite temperature, the thermal motion fluctuates the structures. We defined a fluctuation function with the distance matrix of a cluster. The fluctuation has been studied with the Monte-Carlo simulation method. Our studies show that the clusters remain in the solid state when temperature is low. The small values of fluctuation functions indicates the thermal vibration of atoms around their equilibrium positions. If the temperature is high, the atoms are delocalized. The cluster melts and enters the liquid region. The cluster melting is simulated by the Monte-Carlo simulation with the fluctuation function we defined. Energy levels of clusters are calculated from the Hubbard model. Ionization potentials and magic numbers are also obtained from these energy levels. The results confirm that the Hubbard model is a good approximation for a small cluster. The excitation energy is presented by the difference between the original level and excited level, and the electron-hole interactions. We also have studied cooling of clusters

  17. The Effect of Improved Water Supply on Diarrhea Prevalence of Children under Five in the Volta Region of Ghana: A Cluster-Randomized Controlled Trial

    PubMed Central

    Cha, Seungman; Kang, Douk; Tuffuor, Benedict; Lee, Gyuhong; Cho, Jungmyung; Chung, Jihye; Kim, Myongjin; Lee, Hoonsang; Lee, Jaeeun; Oh, Chunghyeon

    2015-01-01

    Although a number of studies have been conducted to explore the effect of water quality improvement, the majority of them have focused mainly on point-of-use water treatment, and the studies investigating the effect of improved water supply have been based on observational or inadequately randomized trials. We report the results of a matched cluster randomized trial investigating the effect of improved water supply on diarrheal prevalence of children under five living in rural areas of the Volta Region in Ghana. We compared the diarrheal prevalence of 305 children in 10 communities of intervention with 302 children in 10 matched communities with no intervention (October 2012 to February 2014). A modified Poisson regression was used to estimate the prevalence ratio. An intention-to-treat analysis was undertaken. The crude prevalence ratio of diarrhea in the intervention compared with the control communities was 0.85 (95% CI 0.74–0.97) for Krachi West, 0.96 (0.87–1.05) for Krachi East, and 0.91 (0.83–0.98) for both districts. Sanitation was adjusted for in the model to remove the bias due to residual imbalance since it was not balanced even after randomization. The adjusted prevalence ratio was 0.82 (95% CI 0.71–0.96) for Krachi West, 0.95 (0.86–1.04) for Krachi East, and 0.89 (0.82–0.97) for both districts. This study provides a basis for a better approach to water quality interventions. PMID:26404337

  18. Dynamic regional phase synchrony (DRePS): An Instantaneous Measure of Local fMRI Connectivity Within Spatially Clustered Brain Areas.

    PubMed

    Omidvarnia, Amir; Pedersen, Mangor; Walz, Jennifer M; Vaughan, David N; Abbott, David F; Jackson, Graeme D

    2016-05-01

    Dynamic functional brain connectivity analysis is a fast expanding field in computational neuroscience research with the promise of elucidating brain network interactions. Sliding temporal window based approaches are commonly used in order to explore dynamic behavior of brain networks in task-free functional magnetic resonance imaging (fMRI) data. However, the low effective temporal resolution of sliding window methods fail to capture the full dynamics of brain activity at each time point. These also require subjective decisions regarding window size and window overlap. In this study, we introduce dynamic regional phase synchrony (DRePS), a novel analysis approach that measures mean local instantaneous phase coherence within adjacent fMRI voxels. We evaluate the DRePS framework on simulated data showing that the proposed measure is able to estimate synchrony at higher temporal resolution than sliding windows of local connectivity. We applied DRePS analysis to task-free fMRI data of 20 control subjects, revealing ultra-slow dynamics of local connectivity in different brain areas. Spatial clustering based on the DRePS feature time series reveals biologically congruent local phase synchrony networks (LPSNs). Taken together, our results demonstrate three main findings. Firstly, DRePS has increased temporal sensitivity compared to sliding window correlation analysis in capturing locally synchronous events. Secondly, DRePS of task-free fMRI reveals ultra-slow fluctuations of ∼0.002-0.02 Hz. Lastly, LPSNs provide plausible spatial information about time-varying brain local phase synchrony. With the DRePS method, we introduce a framework for interrogating brain local connectivity, which can potentially provide biomarkers of human brain function in health and disease. Hum Brain Mapp 37:1970-1985, 2016. © 2016 Wiley Periodicals, Inc.

  19. Absorption Cross Sections of 2-Nitrophenol in the 295-400 nm Region and Photolysis of 2-Nitrophenol at 308 and 351 nm.

    PubMed

    Sangwan, Manuvesh; Zhu, Lei

    2016-12-22

    2-Nitrophenol is an important component of "brown carbon" in the atmosphere. Photolysis is its dominant gas phase removal process. We have determined the gas phase absorption cross sections of 2-nitrophenol in the 295-400 nm region by using cavity ring-down spectroscopy. 2-Nitrophenol exhibits a broad absorption band over the wavelength region studied, with the peak absorption located at 345 nm. Absorption cross section values range between (2.86 ± 0.18) × 10(-18) and (2.63 ± 0.31) × 10(-20) cm(2)/molecule over the 295-400 nm range. We have investigated the HONO, NO2, and OH formation channels following the gas phase photolysis of 2-nitrophenol at 308 and 351 nm. Direct NO2 formation was not observed. HONO and OH are direct products from 2-nitrophenol photolysis. The average OH quantum yields from the photolysis of 0.5, 1.0, and 2.0 mTorr of 2-nitrophenol are 0.69 ± 0.07 and 0.70 ± 0.07 at 308 and 351 nm. The average HONO quantum yields are 0.34 ± 0.09 and 0.39 ± 0.07 at 308 and 351 nm. The OH and HONO quantum yields are independent of nitrogen carrier gas pressure in the 20-600 Torr range. Oxidant formation rate constants from 2-nitrophenol photolysis have been calculated. Discussions have been made concerning the role of 2-nitrophenol gas phase photolysis in the formation of atmospheric oxidants in regions of high anthropogenic emissions.

  20. A cross-sectional study of the appropriateness of colonoscopy requests in the Spanish region of Catalonia

    PubMed Central

    Puente, Diana; Cantero, Francesc Xavier; Llagostera, Maria; Piñeiro, Pilar; Nieto, Raquel; Saladich, Rosa; Mascort, Juanjo; Marzo, Mercè; Almeda, Jesús; Segarra, Manel

    2012-01-01

    Introduction Colonoscopies are being requested with increasing frequency in the last few years, as they are used both as a diagnostic and therapeutic procedure in several gastrointestinal diseases. Our purpose is to describe the appropriateness of colonoscopy requests issued both from primary care centres and from hospitals, according to the EPAGE II guidelines (European Panel on the Appropriateness of Gastrointestinal Endoscopy). Methods and analysis Cross-sectional study. Colonoscopy requests issued since January 2011 and received at the endoscopy units of all six reference hospitals serving the primary care centres of the South Metropolitan and Central Catalonia districts will be collected (total=1500 requests). Variables to be collected include gender, date of birth, origin of the request and reference hospital, priority of the procedure, type of clinician requesting the procedure, date and indication of request, abdominal examination performed, anal inspection examination performed, date of last colonoscopy if applicable, diagnosis and date of diagnosis. Using the available information and the EPAGE II website, colonoscopy requests will be assigned as an appropriateness score. The association between the variables collected and the EPAGE II scores will be assessed using a Student's t test and a χ2 test. A multilevel logistic model will be generated on the factors associated with the appropriateness of the requests. Ethics and dissemination Colonoscopy is a costly procedure and not free from complications. In order to increase cost effectiveness, reduce waiting lists and optimise resources, it is necessary to use tools such as the EPAGE II guidelines, which establish criteria to assess the appropriateness of colonoscopies. The purpose of this study is to describe the current situation and to discuss whether current clinical practice is appropriate. The results of the study will be published in the next few years. In consideration of the ethical principles and

  1. Factors Associated with Job Satisfaction among University Teachers in Northeastern Region of China: A Cross-Sectional Study

    PubMed Central

    Pan, Bochen; Shen, Xue; Liu, Li; Yang, Yilong; Wang, Lie

    2015-01-01

    Objective: Teachers’ job satisfaction is one of the key factors in institutional dynamics and is generally considered to be the primary variable by which the effectiveness of an organization’s human resource is evaluated. The objectives of this study were to assess the level of job satisfaction among university teachers and to clarify the associated factors. Method: A cross-sectional study was conducted between November 2013 and January 2014. Teachers from six universities in Shenyang, China were randomly sampled. The job satisfaction scale Minnesota Satisfaction Questionnaire (MSQ), perceived organizational support (POS), psychological capital questionnaire (PCQ-24), and effort-reward imbalance scale (ERI) together with questions about demographic and working factors were administered in questionnaires distributed to 1500 university teachers. Hierarchical linear regression analyses were performed to explore the related factors. Results: 1210 effective responses were obtained (effective respondent rate 80.7%). The average score of overall job satisfaction was 69.71. Hierarchical linear regression analysis revealed that turnover intention, occupational stress and chronic disease all had negative impacts on job satisfaction, whereas perceived organizational support, psychological capital and higher monthly income were positively associated with job satisfaction among the university teachers. Age was also linked to the level of job satisfaction. All the variables explained 60.7% of the variance in job satisfaction. Conclusions: Chinese university teachers had a moderate level of job satisfaction. Demographic and working characteristics were associated factors for job satisfaction. Perceived organizational support showed the strongest association with job satisfaction. Results of the study indicate that improving the perceived organizational support may increase the level of job satisfaction for university teachers. PMID:26473906

  2. Revised geologic cross sections of parts of the Colorado, White River, and Death Valley regional groundwater flow systems, Nevada, Utah, and Arizona

    USGS Publications Warehouse

    Page, William R.; Scheirer, Daniel S.; Langenheim, V.E.; Berger, Mary A.

    2006-01-01

    This report presents revisions to parts of seven of the ten cross sections originally published in U.S. Geological Survey Open-File Report 2006-1040. The revisions were necessary to correct errors in some of the original cross sections, and to show new parts of several sections that were extended and (or) appended to the original section profiles. Revisions were made to cross sections C-C', D-D', E-E', F-F', G-G', I-I', and J-J', and the parts of the sections revised or extended are highlighted below the sections on plate 1 by red brackets and the word "revised," or "extended." Sections not listed above, as well as the interpretive text and figures, are generally unchanged from the original report. Cross section C-C' includes revisions in the east Mormon Mountains in the east part of the section; D-D' includes revisions in the Mormon Mesa area in the east part of the section; E-E' includes revisions in the Muddy Mountains in the east part of the section; F-F' includes revisions from the Muddy Mountains to the south Virgin Mountains in the east part of the section; and J-J' includes some revisions from the east Mormon Mountains to the Virgin Mountains. The east end of G-G' was extended about 16 km from the Black Mountains to the southern Virgin Mountains, and the northern end of I-I' was extended about 45 km from the Muddy Mountains to the Mormon Mountains, and revisions were made in the Muddy Mountains part of the original section. This report contains 10 interpretive cross sections and an integrated text describing the geology of parts of the Colorado, White River, and Death Valley regional groundwater flow systems in Nevada, Utah, and Arizona. The primary purpose of the report is to provide geologic framework data for input into a numerical groundwater model. Therefore, the stratigraphic and structural summaries are written in a hydrogeologic context. The oldest rocks (basement) are Early Proterozoic metamorphic and intrusive crystalline rocks that are considered

  3. Cluster headache

    MedlinePlus

    Histamine headache; Headache - histamine; Migrainous neuralgia; Headache - cluster; Horton's headache; Vascular headache - cluster ... be related to the body's sudden release of histamine (chemical in the body released during an allergic ...

  4. Cross-regional prediction of long-term trajectory of stream water DOC response to climate change

    NASA Astrophysics Data System (ADS)

    Laudon, Hjalmar; Buttle, Jim; Carey, Sean K.; McDonnell, Jeff; McGuire, Kevin; Seibert, Jan; Shanley, Jamie; Soulsby, Chris; Tetzlaff, Doerthe

    2012-09-01

    There is no scientific consensus about how dissolved organic carbon (DOC) in surface waters is regulated. Here we combine recent literature data from 49 catchments with detailed stream and catchment process information from nine well established research catchments at mid- to high latitudes to examine the question of how climate controls stream water DOC. We show for the first time that mean annual temperature (MAT) in the range from -3° to +10° C has a strong control over the regional stream water DOC concentration in catchments, with highest concentrations in areas ranging between 0° and +3° C MAT. Although relatively large deviations from this model occur for individual streams, catchment topography appears to explain much of this divergence. These findings suggest that the long-term trajectory of stream water DOC response to climate change may be more predictable than