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Sample records for hidden population substructure

  1. Using Network Methodology to Infer Population Substructure.

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    Dmitry Prokopenko

    Full Text Available One of the main caveats of association studies is the possible affection by bias due to population stratification. Existing methods rely on model-based approaches like structure and ADMIXTURE or on principal component analysis like EIGENSTRAT. Here we provide a novel visualization technique and describe the problem of population substructure from a graph-theoretical point of view. We group the sequenced individuals into triads, which depict the relational structure, on the basis of a predefined pairwise similarity measure. We then merge the triads into a network and apply community detection algorithms in order to identify homogeneous subgroups or communities, which can further be incorporated as covariates into logistic regression. We apply our method to populations from different continents in the 1000 Genomes Project and evaluate the type 1 error based on the empirical p-values. The application to 1000 Genomes data suggests that the network approach provides a very fine resolution of the underlying ancestral population structure. Besides we show in simulations, that in the presence of discrete population structures, our developed approach maintains the type 1 error more precisely than existing approaches.

  2. Unexpected relationships of substructured populations in Chinese Locusta migratoria

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    Ji Ya-Jie

    2009-06-01

    Full Text Available Abstract Background Highly migratory species are usually expected to have minimal population substructure because strong gene flow has the effect of homogenizing genetic variation over geographical populations, counteracting random drift, selection and mutation. The migratory locust Locusta migratoria belongs to a monotypic genus, and is an infamous pest insect with exceptional migratory ability – with dispersal documented over a thousand kilometers. Its distributional area is greater than that of any other locust or grasshopper, occurring in practically all the temperate and tropical regions of the eastern hemisphere. Consequently, minimal population substructuring is expected. However, in marked contrast to its high dispersal ability, three geographical subspecies have been distinguished in China, with more than nine being biologically and morphologically identified in the world. Such subspecies status has been under considerable debate. Results By multilocus microsatellite genotyping analysis, we provide ample genetic evidence for strong population substructure in this highly migratory insect that conforms to geography. More importantly, our genetic data identified an unexpected cryptic subdivision and demonstrated a strong affiliation of the East China locusts to those in Northwest/Northern China. The migratory locusts in China formed three distinct groups, viz. (1 the Tibetan group, comprising locusts from Tibet and nearby West China high mountain regions; this is congruent with the previously recognized Tibetan subspecies, L. m. tibetensis; (2 the South China group, containing locusts from the Hainan islands; this corresponds to the Southeast Asia oriental tropical subspecies L. m. manilensis; (3 the North China group, including locusts from the Northwest and Northern China (the Asiatic subspecies L. m. migratoria, Central China and Eastern China regions. Therefore, the traditional concept on Locusta subspecies status established from

  3. Identification of population substructure among Jews using STR markers and dependence on reference populations included

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    Mutirangura Apiwat

    2010-06-01

    Full Text Available Abstract Background Detecting population substructure is a critical issue for association studies of health behaviors and other traits. Whether inherent in the population or an artifact of marker choice, determining aspects of a population's genetic history as potential sources of substructure can aid in design of future genetic studies. Jewish populations, among which association studies are often conducted, have a known history of migrations. As a necessary step in understanding population structure to conduct valid association studies of health behaviors among Israeli Jews, we investigated genetic signatures of this history and quantified substructure to facilitate future investigations of these phenotypes in this population. Results Using 32 autosomal STR markers and the program STRUCTURE, we differentiated between Ashkenazi (AJ, N = 135 and non-Ashkenazi (NAJ, N = 226 Jewish populations in the form of Northern and Southern geographic genetic components (AJ north 73%, south 23%, NAJ north 33%, south 60%. The ability to detect substructure within these closely related populations using a small STR panel was contingent on including additional samples representing major continental populations in the analyses. Conclusions Although clustering programs such as STRUCTURE are designed to assign proportions of ancestry to individuals without reference population information, when Jewish samples were analyzed in the absence of proxy parental populations, substructure within Jews was not detected. Generally, for samples with a given grandparental country of birth, STRUCTURE assignment values to Northern, Southern, African and Asian clusters agreed with mitochondrial DNA and Y-chromosomal data from previous studies as well as historical records of migration and intermarriage.

  4. European population substructure: clustering of northern and southern populations.

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    Michael F Seldin

    2006-09-01

    Full Text Available Using a genome-wide single nucleotide polymorphism (SNP panel, we observed population structure in a diverse group of Europeans and European Americans. Under a variety of conditions and tests, there is a consistent and reproducible distinction between "northern" and "southern" European population groups: most individual participants with southern European ancestry (Italian, Spanish, Portuguese, and Greek have >85% membership in the "southern" population; and most northern, western, eastern, and central Europeans have >90% in the "northern" population group. Ashkenazi Jewish as well as Sephardic Jewish origin also showed >85% membership in the "southern" population, consistent with a later Mediterranean origin of these ethnic groups. Based on this work, we have developed a core set of informative SNP markers that can control for this partition in European population structure in a variety of clinical and genetic studies.

  5. Strong population substructure is correlated with morphology and ecology in a migratory bat.

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    Miller-Butterworth, Cassandra M; Jacobs, David S; Harley, Eric H

    2003-07-10

    Examining patterns of inter-population genetic diversity can provide valuable information about both historical and current evolutionary processes affecting a species. Population genetic studies of flying and migratory species such as bats and birds have traditionally shown minimal population substructure, characterized by high levels of gene flow between populations. In general, strongly substructured mammalian populations either are separated by non-traversable barriers or belong to terrestrial species with low dispersal abilities. Species with female philopatry (the tendency to remain in or consistently return to the natal territory) might show strong substructure when examined with maternally inherited mitochondrial DNA, but this substructure generally disappears when biparentally inherited markers are used, owing to male-mediated gene flow. Male-biased dispersal is considered typical for mammals, and philopatry in both sexes is rare. Here we show strong population substructure in a migratory bat species, and philopatry in both sexes, as indicated by concordance of nuclear and mtDNA findings. Furthermore, the genetic structure correlates with local biomes and differentiation in wing morphology. There is therefore a close correlation of genetic and morphological differentiation in sympatric subspecific populations of this mammalian species.

  6. Substructure in the Most Massive GEEC Groups: Field-like Populations in Dynamically Active Groups

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    Hou, Annie; Wilman, David J; McGee, Sean L; Harris, William E; Connelly, Jennifer L; Balogh, Michael L; Mulchaey, John S; Bower, Richard G

    2012-01-01

    The presence of substructure in galaxy groups and clusters is believed to be a sign of recent galaxy accretion and can be used not only to probe the assembly history of these structures, but also the evolution of their member galaxies. Using the Dressler-Shectman (DS) Test, we study substructure in a sample of intermediate redshift (z ~ 0.4) galaxy groups from the Group Environment and Evolution Collaboration (GEEC) group catalog. We find that 4 of the 15 rich GEEC groups, with an average velocity dispersion of ~525 km s-1, are identified as having significant substructure. The identified regions of localized substructure lie on the group outskirts and in some cases appear to be infalling. In a comparison of galaxy properties for the members of groups with and without substructure, we find that the groups with substructure have a significantly higher fraction of blue and star-forming galaxies and a parent colour distribution that resembles that of the field population rather than the overall group population....

  7. GESP: A computer program for modeling genetic effective population size, inbreeding, and divergence in substructured populations.

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    Olsson, Fredrik; Laikre, Linda; Hössjer, Ola; Ryman, Nils

    2017-03-24

    The genetically effective population size (Ne) is of key importance for quantifying rates of inbreeding and genetic drift, and is often used in conservation management to set targets for genetic viability. The concept was developed for single, isolated populations and the mathematical means for analyzing the expected Ne in complex, subdivided populations have previously not been available. We recently developed such analytical theory and central parts of that work have now been incorporated into a freely available software tool presented here. GESP (Genetic Effective population size, inbreeding, and divergence in Substructured Populations) is R-based and designed to model short and long term patterns of genetic differentiation and effective population size of subdivided populations. The algorithms performed by GESP allow exact computation of global and local inbreeding and eigenvalue effective population size, predictions of genetic divergence among populations (GST) as well as departures from random mating (FIS, FIT) while varying i) subpopulation census and effective size, separately or including trend of the global population size, ii) rate and direction of migration between all pairs of subpopulations, iii) degree of relatedness and divergence among subpopulations, iv) ploidy (haploid or diploid), and v) degree of selfing. Here, we describe GESP and exemplify its use in conservation genetics modeling. This article is protected by copyright. All rights reserved.

  8. An ALMA Search for Substructure, Fragmentation, and Hidden Protostars in Starless Cores in Chamaeleon I

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    Dunham, Michael M; Pineda, Jaime E; Bourke, Tyler L; Tobin, John J; Arce, Héctor G; Chen, Xuepeng; Di Francesco, James; Johnstone, Doug; Lee, Katherine I; Myers, Philip C; Price, Daniel; Sadavoy, Sarah I; Schnee, Scott

    2016-01-01

    We present an Atacama Large Millimeter/submillimeter Array (ALMA) 106 GHz (Band 3) continuum survey of the complete population of dense cores in the Chamaeleon I molecular cloud. We detect a total of 24 continuum sources in 19 different target fields. All previously known Class 0 and Class I protostars in Chamaeleon I are detected, whereas all of the 56 starless cores in our sample are undetected. We show that the Spitzer+Herschel census of protostars in Chamaeleon I is complete, with the rate at which protostellar cores have been misclassified as starless cores calculated as <1/56, or < 2%. We use synthetic observations to show that starless cores collapsing following the turbulent fragmentation scenario are detectable by our ALMA observations when their central densities exceed ~10^8 cm^-3, with the exact density dependent on the viewing geometry. Bonnor-Ebert spheres, on the other hand, remain undetected to central densities at least as high as 10^10 cm^-3. Our starless core non-detections are used t...

  9. Association between Y haplogroups and autosomal AIMs reveals intra-population substructure in Bolivian populations.

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    Vullo, Carlos; Gomes, Verónica; Romanini, Carola; Oliveira, Andréa M; Rocabado, Omar; Aquino, Juliana; Amorim, António; Gusmão, Leonor

    2015-07-01

    For the correct evaluation of the weight of genetic evidence in a forensic context, databases must reflect the structure of the population, with all possible groups being represented. Countries with a recent history of admixture between strongly differentiated populations are usually highly heterogeneous and sub-structured. Bolivia is one of these countries, with a high diversity of ethnic groups and different levels of admixture (among Native Americans, Europeans and Africans) across the territory. For a better characterization of the male lineages in Bolivia, 17 Y-STR and 42 Y-SNP loci were genotyped in samples from La Paz and Chuquisaca. Only European and Native American Y-haplogroups were detected, and no sub-Saharan African chromosomes were found. Significant differences were observed between the two samples, with a higher frequency of European lineages in Chuquisaca than in La Paz. A sample belonging to haplogroup Q1a3a1a1-M19 was detected in La Paz, in a haplotype background different from those previously found in Argentina. This result supports an old M19 North-south dispersion in South America, possibly via two routes. When comparing the ancestry of each individual assessed through his Y chromosome with the one estimated using autosomal AIMs, (a) increased European ancestry in individuals with European Y chromosomes and (b) higher Native American ancestry in the carriers of Native American Y-haplogroups were observed, revealing an association between autosomal and Y-chromosomal markers. The results of this study demonstrate that a sub-structure does exist in Bolivia at both inter- and intrapopulation levels, a fact which must be taken into account in the evaluation of forensic genetic evidence.

  10. Genetic substructure of Kuwaiti population reveals migration history.

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    Osama Alsmadi

    Full Text Available The State of Kuwait is characterized by settlers from Saudi Arabia, Iran, and other regions of the Arabian Peninsula. The settlements and subsequent admixtures have shaped the genetics of Kuwait. High prevalence of recessive disorders and metabolic syndromes (that increase risk of diabetes is seen in the peninsula. Understanding the genetic structure of its population will aid studies designed to decipher the underlying causes of these disorders. In this study, we analyzed 572,366 SNP markers from 273 Kuwaiti natives genotyped using the illumina HumanOmniExpress BeadChip. Model-based clustering identified three genetic subgroups with different levels of admixture. A high level of concordance (Mantel test, p=0.0001 for 9999 repeats was observed between the derived genetic clusters and the surname-based ancestries. Use of Human Genome Diversity Project (HGDP data to understand admixtures in each group reveals the following: the first group (Kuwait P is largely of West Asian ancestry, representing Persians with European admixture; the second group (Kuwait S is predominantly of city-dwelling Saudi Arabian tribe ancestry, and the third group (Kuwait B includes most of the tent-dwelling Bedouin surnames and is characterized by the presence of 17% African ancestry. Identity by Descent and Homozygosity analyses find Kuwait's population to be heterogeneous (placed between populations that have large amount of ROH and the ones with low ROH with Kuwait S as highly endogamous, and Kuwait B as diverse. Population differentiation FST estimates place Kuwait P near Asian populations, Kuwait S near Negev Bedouin tribes, and Kuwait B near the Mozabite population. FST distances between the groups are in the range of 0.005 to 0.008; distances of this magnitude are known to cause false positives in disease association studies. Results of analysis for genetic features such as linkage disequilibrium decay patterns conform to Kuwait's geographical location at the nexus

  11. Genetic population substructure in bison at Yellowstone National Park.

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    Halbert, Natalie D; Gogan, Peter J P; Hedrick, Philip W; Wahl, Jacquelyn M; Derr, James N

    2012-01-01

    The Yellowstone National Park bison herd is 1 of only 2 populations known to have continually persisted on their current landscape since pre-Columbian times. Over the last century, the census size of this herd has fluctuated from around 100 individuals to over 3000 animals. Previous studies involving radiotelemetry, tooth wear, and parturition timing provide evidence of at least 2 distinct groups of bison within Yellowstone National Park. To better understand the biology of Yellowstone bison, we investigated the potential for limited gene flow across this population using multilocus Bayesian clustering analysis. Two genetically distinct and clearly defined subpopulations were identified based on both genotypic diversity and allelic distributions. Genetic cluster assignments were highly correlated with sampling locations for a subgroup of live capture individuals. Furthermore, a comparison of the cluster assignments to the 2 principle winter cull sites revealed critical differences in migration patterns across years. The 2 Yellowstone subpopulations display levels of differentiation that are only slightly less than that between populations which have been geographically and reproductively isolated for over 40 years. The identification of cryptic population subdivision and genetic differentiation of this magnitude highlights the importance of this biological phenomenon in the management of wildlife species.

  12. Mexican mestizo population sub-structure: effects on genetic and forensic statistical parameters.

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    Noris, Gino; Santana, Carla; Meraz-Ríos, Marco Antonio; de Lourdes Munoz, María; Majluf-Cruz, Abraham; Magaña, Jonathan J; Granados, Julio; Quezada, Rosa; Revilla, María Cristina; Martínez-Salas, Sergio; Xihuitl, Salvador; Martínez de la Escalera, Gonzalo; Díaz-Badillo, Alvaro; Calderon-Aranda, Emma S; Gómez, Rocío

    2012-12-01

    Since Mexican mestizos are an admixed population, it is necessary to determine the effects that the substructure of the population has on genetic and forensic parameters. With this aim, a study was performed with 15 STR loci (CODIS plus D2S1338 and D19S433) on 1,640 unrelated Mexican mestizos. We determine allele and genotypic frequencies observing departure from Hardy-Weinberg expectation (12 out of 15 loci, with an excess of homozygotes, Fis > 0), as well as pairs of loci in an apparent linkage disequilibrium (13 of 92 loci). We conducted a test for genetic population stratification, the results show that the Mexican mestizo population is substructured into three subgroups, which are in HW and linkage equilibrium. The combination of the 15 loci in the whole population has high forensic efficiency with the capacity to genetically discriminate one individual in one quintillion (1/10(18)). Our data potentially validates the use of these 15 STR loci to establish forensic identity and parentage testing for legal purposes, and offers a powerful tool for genetic variation analysis. However, given that the population is stratified, we highly recommend applying a correction with the inbreeding coefficient in calculations of paternity and forensic studies to avoid erroneous assumptions.

  13. Accounting for ancestry: population substructure and genome-wide association studies.

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    Tian, Chao; Gregersen, Peter K; Seldin, Michael F

    2008-10-15

    Accounting for the genetic substructure of human populations has become a major practical issue for studying complex genetic disorders. Allele frequency differences among ethnic groups and subgroups and admixture between different ethnic groups can result in frequent false-positive results or reduced power in genetic studies. Here, we review the problems and progress in defining population differences and the application of statistical methods to improve association studies. It is now possible to take into account the confounding effects of population stratification using thousands of unselected genome-wide single-nucleotide polymorphisms or, alternatively, selected panels of ancestry informative markers. These methods do not require any demographic information and therefore can be widely applied to genotypes available from multiple sources. We further suggest that it will be important to explore results in homogeneous population subsets as we seek to define the extent to which genomic variation influences complex phenotypes.

  14. GAGA: A New Algorithm for Genomic Inference of Geographic Ancestry Reveals Fine Level Population Substructure in Europeans

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    O. Lao Grueso (Oscar); F. Liu (Fan); A. Wollstein (Andreas); M.H. Kayser (Manfred)

    2014-01-01

    textabstractAttempts to detect genetic population substructure in humans are troubled by the fact that the vast majority of the total amount of observed genetic variation is present within populations rather than between populations. Here we introduce a new algorithm for transforming a genetic dista

  15. B-graph sampling to estimate the size of a hidden population

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    Spreen, M.; Bogaerts, S.

    2015-01-01

    Link-tracing designs are often used to estimate the size of hidden populations by utilizing the relational links between their members. A major problem in studies of hidden populations is the lack of a convenient sampling frame. The most frequently applied design in studies of hidden populations is

  16. On the Recombination Rate Estimation in the Presence of Population Substructure.

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    Julian Hecker

    Full Text Available As recombination events are not uniformly distributed along the human genome, the estimation of fine-scale recombination maps, e.g. HapMap Project, has been one of the major research endeavors over the last couple of years. For simulation studies, these estimates provide realistic reference scenarios to design future study and to develop novel methodology. To achieve a feasible framework for the estimation of such recombination maps, existing methodology uses sample probabilities for a two-locus model with recombination, with recent advances allowing for computationally fast implementations. In this work, we extend the existing theoretical framework for the recombination rate estimation to the presence of population substructure. We show under which assumptions the existing methodology can still be applied. We illustrate our extension of the methodology by an extensive simulation study.

  17. A Consensus Tree Approach for Reconstructing Human Evolutionary History and Detecting Population Substructure

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    Tsai, Ming-Chi; Blelloch, Guy; Ravi, R.; Schwartz, Russell

    The random accumulation of variations in the human genome over time implicitly encodes a history of how human populations have arisen, dispersed, and intermixed since we emerged as a species. Reconstructing that history is a challenging computational and statistical problem but has important applications both to basic research and to the discovery of genotype-phenotype correlations. In this study, we present a novel approach to inferring human evolutionary history from genetic variation data. Our approach uses the idea of consensus trees, a technique generally used to reconcile species trees from divergent gene trees, adapting it to the problem of finding the robust relationships within a set of intraspecies phylogenies derived from local regions of the genome. We assess the quality of the method on two large-scale genetic variation data sets: the HapMap Phase II and the Human Genome Diversity Project. Qualitative comparison to a consensus model of the evolution of modern human population groups shows that our inferences closely match our best current understanding of human evolutionary history. A further comparison with results of a leading method for the simpler problem of population substructure assignment verifies that our method provides comparable accuracy in identifying meaningful population subgroups in addition to inferring the relationships among them.

  18. Lactase persistence-related genetic variant: population substructure and health outcomes.

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    Smith, George Davey; Lawlor, Debbie A; Timpson, Nic J; Baban, Jamil; Kiessling, Matt; Day, Ian N M; Ebrahim, Shah

    2009-03-01

    Lactase persistence is an autosomal-dominant trait that is common in European-derived populations. A basic tendency for lactase persistence to increase from the southeast to the northwest across European populations has been noted, but such trends within countries have not been extensively studied. We genotyped the C/T(-13910) variant (rs4988235) that constitutes the putatively causal allele for lactase persistence (T allele representing persistence) in a general population sample of 3344 women aged 60-79 years from 23 towns across Britain. We found an overall frequency of 0.253 for the C (lactase non-persistence) allele, but with considerable gradients of decreasing frequency from the south to the north and from the east to the west of Britain for this allele. Daily sunlight was positively related to C (non-persistence) allele prevalence. However, sunlight exposure and latitude are strongly correlated, and it was not possible to identify which is the primary factor statistically underlying the distribution of lactase persistence. The C/T(-13910) variant (rs4988235) was not related to drinking milk or bone health (although drinking milk itself was protective of bone health), and was essentially unrelated to a wide range of other lifestyle, health and demographic characteristics. One exception was general health being rated as being poor or fair, for which there was an odds ratio of 1.38 (1.04, 1.84) for women homozygous for the C allele; on adjustment for latitude and longitude of place of birth, this attenuated to 1.19 (0.87, 1.64). The lactase persistence variant could contribute to the examination of data for the existence of, and then statistical control for, population substructure in genetic association studies.

  19. The Hidden Complexity of Mendelian Traits across Natural Yeast Populations

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    Jing Hou

    2016-07-01

    Full Text Available Mendelian traits are considered to be at the lower end of the complexity spectrum of heritable phenotypes. However, more than a century after the rediscovery of Mendel’s law, the global landscape of monogenic variants, as well as their effects and inheritance patterns within natural populations, is still not well understood. Using the yeast Saccharomyces cerevisiae, we performed a species-wide survey of Mendelian traits across a large population of isolates. We generated offspring from 41 unique parental pairs and analyzed 1,105 cross/trait combinations. We found that 8.9% of the cases were Mendelian. Further tracing of causal variants revealed background-specific expressivity and modified inheritances, gradually transitioning from Mendelian to complex traits in 30% of the cases. In fact, when taking into account the natural population diversity, the hidden complexity of traits could be substantial, confounding phenotypic predictability even for simple Mendelian traits.

  20. Association of Systemic Lupus Erythematosus Clinical Features with European Population Genetic Substructure

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    Calaza, Manuel; Witte, Torsten; Papasteriades, Chryssa; Marchini, Maurizio; Migliaresi, Sergio; Kovacs, Attila; Ordi-Ros, Josep; Bijl, Marc; Santos, Maria Jose; Ruzickova, Sarka; Pullmann, Rudolf; Carreira, Patricia; Skopouli, Fotini N.; D'Alfonso, Sandra; Sebastiani, Gian Domenico; Suarez, Ana; Blanco, Francisco J.; Gomez-Reino, Juan J.; Gonzalez, Antonio

    2011-01-01

    Systemic Lupus Erythematosus (SLE) is an autoimmune disease with a very varied spectrum of clinical manifestations that could be partly determined by genetic factors. We aimed to determine the relationship between prevalence of 11 clinical features and age of disease onset with European population genetic substructure. Data from 1413 patients of European ancestry recruited in nine countries was tested for association with genotypes of top ancestry informative markers. This analysis was done with logistic regression between phenotypes and genotypes or principal components extracted from them. We used a genetic additive model and adjusted for gender and disease duration. Three clinical features showed association with ancestry informative markers: autoantibody production defined as immunologic disorder (P = 6.8×10−4), oral ulcers (P = 6.9×10−4) and photosensitivity (P = 0.002). Immunologic disorder was associated with genotypes more common in Southern European ancestries, whereas the opposite trend was observed for photosensitivity. Oral ulcers were specifically more common in patients of Spanish and Portuguese self-reported ancestry. These results should be taken into account in future research and suggest new hypotheses and possible underlying mechanisms to be investigated. A first hypothesis linking photosensitivity with variation in skin pigmentation is suggested. PMID:22194982

  1. Analysis of population substructure in two sympatric populations of Gran Chaco, Argentina.

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    Sevini, Federica; Yao, Daniele Yang; Lomartire, Laura; Barbieri, Annalaura; Vianello, Dario; Ferri, Gianmarco; Moretti, Edgardo; Dasso, Maria Cristina; Garagnani, Paolo; Pettener, Davide; Franceschi, Claudio; Luiselli, Donata; Franceschi, Zelda Alice

    2013-01-01

    Sub-population structure and intricate kinship dynamics might introduce biases in molecular anthropology studies and could invalidate the efforts to understand diseases in highly admixed populations. In order to clarify the previously observed distribution pattern and morbidity of Chagas disease in Gran Chaco, Argentina, we studied two populations (Wichí and Criollos) recruited following an innovative bio-cultural model considering their complex cultural interactions. By reconstructing the genetic background and the structure of these two culturally different populations, the pattern of admixture, the correspondence between genealogical and genetic relationships, this integrated perspective had the power to validate data and to link the gap usually relying on a singular discipline. Although Wichí and Criollos share the same area, these sympatric populations are differentiated from the genetic point of view as revealed by Non Recombinant Y Chromosome genotyping resulting in significantly high Fst values and in a lower genetic variability in the Wichí population. Surprisingly, the Amerindian and the European components emerged with comparable amounts (20%) among Criollos and Wichí respectively. The detailed analysis of mitochondrial DNA showed that the two populations have as much as 87% of private haplotypes. Moreover, from the maternal perspective, despite a common Amerindian origin, an Andean and an Amazonian component emerged in Criollos and in Wichí respectively. Our approach allowed us to highlight that quite frequently there is a discrepancy between self-reported and genetic kinship. Indeed, if self-reported identity and kinship are usually utilized in population genetics as a reliable proxy for genetic identity and parental relationship, in our model populations appear to be the result not only and not simply of the genetic background but also of complex cultural determinants. This integrated approach paves the way to a rigorous reconstruction of

  2. Assessing individual interethnic admixture and population substructure using a 48-insertion-deletion (INSEL) ancestry-informative marker (AIM) panel.

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    Santos, Ney P C; Ribeiro-Rodrigues, Elzemar M; Ribeiro-Dos-Santos, Andrea K C; Pereira, Rui; Gusmão, Leonor; Amorim, António; Guerreiro, Joáo F; Zago, Marco A; Matte, Cecília; Hutz, Mara H; Santos, Sidney E B

    2010-02-01

    Estimating the proportions of different ancestries in admixed populations is very important in population genetics studies, and it is particularly important for detecting population substructure effects in case-control association studies. In this work, a set of 48 ancestry-informative insertion-deletion polymorphisms (INDELs) were selected with the goal of efficiently measuring the proportions of three different ancestries (sub-Saharan African, European, and Native American) in mixed populations. All selected markers can be easily analyzed via multiplex PCR and detected with standard capillary electrophoresis. A total of 593 unrelated individuals representative of European, African, and Native American parental populations were typed, as were 380 individuals from three Brazilian populations with known admixture patterns. As expected, the interethnic admixture estimates show that individuals from southern Brazil present an almost exclusively European ancestry; Afro-descendant communities in the Amazon region, apart from the major African contribution, present some degree of admixture with Europeans and Native Americans; and a sample from Belém, in the northeastern Amazon, shows a significant contribution of the three ethnic groups, although with a greater European proportion. In summary, a panel of ancestry-informative INDELs was optimized and proven to be a valuable tool for estimating individual and global ancestry proportions in admixed populations. The ability to accurately infer interethnic admixtures highlights the usefulness of this marker set for assessing population substructure in association studies, particularly those conducted in Brazilian and other Latin American populations sharing trihybrid ancestry patterns.

  3. European Population Genetic Substructure: Further Definition of Ancestry Informative Markers for Distinguishing Among Diverse European Ethnic Groups

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    Tian, Chao; Kosoy, Roman; Nassir, Rami; Lee, Annette; Villoslada, Pablo; Klareskog, Lars; Hammarström, Lennart; Garchon, Henri-Jean; Pulver, Ann E.; Ransom, Michael; Gregersen, Peter K.; Seldin, Michael F.

    2009-01-01

    The definition of European population genetic substructure and its application to understanding complex phenotypes is becoming increasingly important. In the current study using over 4000 subjects genotyped for 300 thousand SNPs we provide further insight into relationships among European population groups and identify sets of SNP ancestry informative markers (AIMs) for application in genetic studies. In general, the graphical description of these principal components analyses (PCA) of diverse European subjects showed a strong correspondence to the geographical relationships of specific countries or regions of origin. Clearer separation of different ethnic and regional populations was observed when northern and southern European groups were considered separately and the PCA results were influenced by the inclusion or exclusion of different self-identified population groups including Ashkenazi Jewish, Sardinian and Orcadian ethnic groups. SNP AIM sets were identified that could distinguish the regional and ethnic population groups. Moreover, the studies demonstrated that most allele frequency differences between different European groups could be effectively controlled in analyses using these AIM sets. The European substructure AIMs should be widely applicable to ongoing studies to confirm and delineate specific disease susceptibility candidate regions without the necessity to perform additional genome-wide SNP studies in additional subject sets. PMID:19707526

  4. European population genetic substructure: further definition of ancestry informative markers for distinguishing among diverse European ethnic groups.

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    Tian, Chao; Kosoy, Roman; Nassir, Rami; Lee, Annette; Villoslada, Pablo; Klareskog, Lars; Hammarström, Lennart; Garchon, Henri-Jean; Pulver, Ann E; Ransom, Michael; Gregersen, Peter K; Seldin, Michael F

    2009-01-01

    The definition of European population genetic substructure and its application to understanding complex phenotypes is becoming increasingly important. In the current study using over 4,000 subjects genotyped for 300,000 single-nucleotide polymorphisms (SNPs), we provide further insight into relationships among European population groups and identify sets of SNP ancestry informative markers (AIMs) for application in genetic studies. In general, the graphical description of these principal components analyses (PCA) of diverse European subjects showed a strong correspondence to the geographical relationships of specific countries or regions of origin. Clearer separation of different ethnic and regional populations was observed when northern and southern European groups were considered separately and the PCA results were influenced by the inclusion or exclusion of different self-identified population groups including Ashkenazi Jewish, Sardinian, and Orcadian ethnic groups. SNP AIM sets were identified that could distinguish the regional and ethnic population groups. Moreover, the studies demonstrated that most allele frequency differences between different European groups could be controlled effectively in analyses using these AIM sets. The European substructure AIMs should be widely applicable to ongoing studies to confirm and delineate specific disease susceptibility candidate regions without the necessity of performing additional genome-wide SNP studies in additional subject sets.

  5. CLASH-VLT: Substructure in the galaxy cluster MACS J1206.2-0847 from kinematics of galaxy populations

    CERN Document Server

    Girardi, M; Balestra, I; Nonino, M; Biviano, A; Grillo, C; Rosati, P; Annunziatella, M; Demarco, R; Fritz, A; Gobat, R; Lemze, D; Presotto, V; Scodeggio, M; Tozzi, P; Caminha, G Bartosch; Brescia, M; Coe, D; Kelson, D; Koekemoer, A; Lombardi, M; Medezinski, E; Postman, M; Sartoris, B; Umetsu, K; Zitrin, A; Boschin, W; Czoske, O; De Lucia, G; Kuchner, U; Maier, C; Meneghetti, M; Monaco, P; Monna, A; Munari, E; Seitz, S; Verdugo, M; Ziegler, B

    2015-01-01

    In the effort to understand the link between the structure of galaxy clusters and their galaxy populations, we focus on MACS J1206.2-0847, at z~0.44, probing its substructure in the projected phase space through the spectrophotometric properties of a large number of galaxies from the CLASH-VLT survey. Our analysis is mainly based on an extensive spectroscopic dataset of 445 member galaxies, mostly acquired with VIMOS@VLT as part of our ESO Large Programme, sampling the cluster out to a radius ~2R200 (4 Mpc). We classify 412 galaxies as: passive, with strong Hdelta absorption (red and blue ones), and with emission lines from weak to very strong ones. A number of tests for substructure detection is applied to analyze the galaxy distribution in the velocity space, in the 2D space, and in the (3D) projected phase-space. Studied in its entirety, the cluster appears as a large-scale relaxed system with a few, secondary, minor overdensities in 2D distribution. We detect no velocity gradient or evidence of deviations...

  6. Population genetic analysis and sub-structuring of Theileria parva in the northern and eastern parts of Zambia

    Directory of Open Access Journals (Sweden)

    Muleya Walter

    2012-11-01

    Full Text Available Abstract Background Theileriosis, caused by Theileria parva, is an economically important disease in Africa. It is a major constraint to the development of the livestock industry in some parts of eastern, central and southern Africa. In Zambia, theileriosis causes losses of up to 10,000 cattle annually. Methods Cattle blood samples were collected for genetic analysis of Theileria parva from Isoka and Petauke districts in Zambia. Microsatellite analysis was then performed on all Theileria parva positive samples for PCR using a panel of 9 microsatellite markers. Microsatellite data was analyzed using microsatellite toolkit, GenAlEx ver. 6, Fstat ver. 2.9.3.2, and LIAN computer softwares. Results The combined percentage of positive samples in both districts determined by PCR using the p104 gene primers was 54.9% (95% CI: 46.7 – 63.1%, 78/142, while in each district, it was 44.8% (95% CI: 34.8 – 54.8% and 76.1% (95% CI = 63.9 – 88.4% for Isoka and Petauke districts, respectively. We analyzed the population genetic structure of Theileria parva from a total of 61 samples (33 from Isoka and 28 from Petauke using a panel of 9 microsatellite markers encompassing the 4 chromosomes of Theileria parva. Wright’s F index (FST = 0.178 showed significant differentiation between the Isoka and Petauke populations. Linkage disequilibrium was observed when populations from both districts were treated as a single population. When analyzed separately, linkage disequilibrium was observed in Kanyelele and Kalembe areas in Isoka district, Isoka district overall and in Petauke district. Petauke district had a higher multiplicity of infection than Isoka district. Conclusion Population genetic analyses of Theileria parva from Isoka and Petauke districts showed a low level of genotype exchange between the districts, but a high level of genetic diversity within each district population, implying genetic and geographic sub-structuring between the districts. The sub-structuring

  7. Genetic variation and population substructure in outbred CD-1 mice: implications for genome-wide association studies.

    Directory of Open Access Journals (Sweden)

    Kimberly A Aldinger

    Full Text Available Outbred laboratory mouse populations are widely used in biomedical research. Since little is known about the degree of genetic variation present in these populations, they are not widely used for genetic studies. Commercially available outbred CD-1 mice are drawn from an extremely large breeding population that has accumulated many recombination events, which is desirable for genome-wide association studies. We therefore examined the degree of genome-wide variation within CD-1 mice to investigate their suitability for genetic studies. The CD-1 mouse genome displays patterns of linkage disequilibrium and heterogeneity similar to wild-caught mice. Population substructure and phenotypic differences were observed among CD-1 mice obtained from different breeding facilities. Differences in genetic variation among CD-1 mice from distinct facilities were similar to genetic differences detected between closely related human populations, consistent with a founder effect. This first large-scale genetic analysis of the outbred CD-1 mouse strain provides important considerations for the design and analysis of genetic studies in CD-1 mice.

  8. PERSONAL NETWORK SAMPLING, OUTDEGREE ANALYSIS AND MULTILEVEL ANALYSIS - INTRODUCING THE NETWORK CONCEPT IN STUDIES OF HIDDEN POPULATIONS

    NARCIS (Netherlands)

    SPREEN, M; ZWAAGSTRA, R

    1994-01-01

    Populations, such as heroin and cocaine users, the homeless and the like (hidden populations), are among the most difficult populations to which to apply classic random sampling procedures. A frequently used data collection method for these hidden populations is the snowball procedure. The prerequis

  9. Within-population genetic structure in beech (Fagus sylvatica L. stands characterized by different disturbance histories: does forest management simplify population substructure?

    Directory of Open Access Journals (Sweden)

    Andrea Piotti

    Full Text Available The fine-scale assessment of both spatially and non-spatially distributed genetic variation is crucial to preserve forest genetic resources through appropriate forest management. Cryptic within-population genetic structure may be more common than previously thought in forest tree populations, which has strong implications for the potential of forests to adapt to environmental change. The present study was aimed at comparing within-population genetic structure in European beech (Fagus sylvatica L. plots experiencing different disturbance levels. Five plot pairs made up by disturbed and undisturbed plots having the same biogeographic history were sampled throughout Europe. Overall, 1298 individuals were analyzed using four highly polymorphic nuclear microsatellite markers (SSRs. Bayesian clustering within plots identified 3 to 11 genetic clusters (within-plot θ ST ranged from 0.025 to 0.124. The proportion of within-population genetic variation due to genetic substructuring (F CluPlot = 0.067 was higher than the differentiation among the 10 plots (F PlotTot = 0.045. Focusing on the comparison between managed and unmanaged plots, disturbance mostly explains differences in the complexity of within-population genetic structure, determining a reduction of the number of genetic clusters present in a standardized area. Our results show that: i genetic substructuring needs to be investigated when studying the within-population genetic structure in forest tree populations, and ii indices describing subtle characteristics of the within-population genetic structure are good candidates for providing early signals of the consequences of forest management, and of disturbance events in general.

  10. Within-population genetic structure in beech (Fagus sylvatica L.) stands characterized by different disturbance histories: does forest management simplify population substructure?

    Science.gov (United States)

    Piotti, Andrea; Leonardi, Stefano; Heuertz, Myriam; Buiteveld, Joukje; Geburek, Thomas; Gerber, Sophie; Kramer, Koen; Vettori, Cristina; Vendramin, Giovanni Giuseppe

    2013-01-01

    The fine-scale assessment of both spatially and non-spatially distributed genetic variation is crucial to preserve forest genetic resources through appropriate forest management. Cryptic within-population genetic structure may be more common than previously thought in forest tree populations, which has strong implications for the potential of forests to adapt to environmental change. The present study was aimed at comparing within-population genetic structure in European beech (Fagus sylvatica L.) plots experiencing different disturbance levels. Five plot pairs made up by disturbed and undisturbed plots having the same biogeographic history were sampled throughout Europe. Overall, 1298 individuals were analyzed using four highly polymorphic nuclear microsatellite markers (SSRs). Bayesian clustering within plots identified 3 to 11 genetic clusters (within-plot θ ST ranged from 0.025 to 0.124). The proportion of within-population genetic variation due to genetic substructuring (F CluPlot = 0.067) was higher than the differentiation among the 10 plots (F PlotTot = 0.045). Focusing on the comparison between managed and unmanaged plots, disturbance mostly explains differences in the complexity of within-population genetic structure, determining a reduction of the number of genetic clusters present in a standardized area. Our results show that: i) genetic substructuring needs to be investigated when studying the within-population genetic structure in forest tree populations, and ii) indices describing subtle characteristics of the within-population genetic structure are good candidates for providing early signals of the consequences of forest management, and of disturbance events in general.

  11. Male flight distance and population substructure in the bumblebee Bombus terrestris.

    Science.gov (United States)

    Kraus, F B; Wolf, S; Moritz, R F A

    2009-01-01

    1. Bumblebees are important pollinators in natural as well as agricultural ecosystems. Estimates of foraging range, population size and genetic population structure so far have been based on worker samples alone. Here we include both males and workers in a population genetic analysis to infer the contribution of males to these important ecological parameters. 2. The population genetic (microsatellite) analyses of Bombus terrestris L. populations on the island of Cabrera (Spain) and Halle (Germany) revealed high heterozygosities (0.60 +/- 0.08 to 0.77 +/- 0.13) and neither a deviation from Hardy-Weinberg equilibrium nor linkage disequilibrium. 3. We detected five colonies (census population size) for the island population and 27 to 68 for the German mainland population. The genetic effective population sizes were N(e) = 7.5 for the island and 40.5 to 102 for the mainland population respectively. 4. There was a significant genetic subdifferentiation between the male and the worker population samples, suggesting that males originated from different and/or more distant colonies than workers. 5. Based on the colony numbers, we estimated the flight range of males, which ranged from 2.6 km to 9.9 km, much further than worker flight ranges. Bumblebee-mediated pollen flow will therefore be much further than expected based on the foraging range of workers alone if males also contribute to pollination.

  12. Genetic sub-structure in western Mediterranean populations revealed by 12 Y-chromosome STR loci

    DEFF Research Database (Denmark)

    Rodríguez, V; Tomas Mas, Carmen; Sánchez, J J

    2008-01-01

    Haplotype and allele frequencies of 12 Y-chromosome short tandem repeat (Y-STR) loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385 a/b, DYS437, DYS438 and DYS439) included in the Powerplex(R) Y System were determined in seven western Mediterranean populations from Valencia, Ma...

  13. Low genetic diversity and minimal population substructure in the endangered Florida manatee: implications for conservation

    Science.gov (United States)

    Tucker, Kimberly Pause; Hunter, Margaret E.; Bonde, Robert K.; Austin, James D.; Clark, Ann Marie; Beck, Cathy A.; McGuire, Peter M.; Oli, Madan K.

    2012-01-01

    Species of management concern that have been affected by human activities typically are characterized by low genetic diversity, which can adversely affect their ability to adapt to environmental changes. We used 18 microsatellite markers to genotype 362 Florida manatees (Trichechus manatus latirostris), and investigated genetic diversity, population structure, and estimated genetically effective population size (Ne). The observed and expected heterozygosity and average number of alleles were 0.455 ± 0.04, 0.479 ± 0.04, and 4.77 ± 0.51, respectively. All measures of Florida manatee genetic diversity were less than averages reported for placental mammals, including fragmented or nonideal populations. Overall estimates of differentiation were low, though significantly greater than zero, and analysis of molecular variance revealed that over 95% of the total variance was among individuals within predefined management units or among individuals along the coastal subpopulations, with only minor portions of variance explained by between group variance. Although genetic issues, as inferred by neutral genetic markers, appear not to be critical at present, the Florida manatee continues to face demographic challenges due to anthropogenic activities and stochastic factors such as red tides, oil spills, and disease outbreaks; these can further reduce genetic diversity of the manatee population.

  14. Population History and Mitochondrial Genetic Substructure of the Rama Amerindians from Nicaragua.

    Science.gov (United States)

    Baldi, Norberto F; Crawford, Michael H

    2016-04-01

    The Rama are a coastal population from southern Nicaragua who in large part were able to resist, at least for a time, the cultural changes and social reorganization brought on by colonial and modern influences. Historical information leaves the Rama origins and biological relationships with nearby extinct and extant groups ambiguous. The objective of this study was to examine the internal genetic microdifferentiation based on the first hypervariable region of the mitochondrial DNA (mtDNA) from a sample of approximately 20% of the population, and to expand the few available historical and anthropological data on the Rama by exploring the effects of cultural practices and historical events on genetic structure, providing an integrative perspective on the Rama genetic history. When considering differences in the spatial distribution and genetic diversity of the mtDNA haplotypes together with historical information on the Rama, a noteworthy pattern emerges. (a) Haplotypes are differentially distributed among a central Rama community (Punta Águila) compared with the other five peripheral communities (analysis of molecular variance: FCT = 0.10, p population after their split from Punta Gorda in the 18th century. (b) Differential genetic signatures found among central and peripheral Rama communities resemble two population histories: one of stability (haplogroup A2) and other of expansion (haplogroup B2), supporting the possibility that these patterns of genetic microdifferentiation between central and peripheral populations resulted from the 18th-century unification in southern Nicaragua of the Rama and a group of Voto migrants from Costa Rica that later split off and moved to the Bay of Bluefields.

  15. Tracing sub-structure in the European American population with PCA-informative markers.

    Directory of Open Access Journals (Sweden)

    Peristera Paschou

    2008-07-01

    Full Text Available Genetic structure in the European American population reflects waves of migration and recent gene flow among different populations. This complex structure can introduce bias in genetic association studies. Using Principal Components Analysis (PCA, we analyze the structure of two independent European American datasets (1,521 individuals-307,315 autosomal SNPs. Individual variation lies across a continuum with some individuals showing high degrees of admixture with non-European populations, as demonstrated through joint analysis with HapMap data. The CEPH Europeans only represent a small fraction of the variation encountered in the larger European American datasets we studied. We interpret the first eigenvector of this data as correlated with ancestry, and we apply an algorithm that we have previously described to select PCA-informative markers (PCAIMs that can reproduce this structure. Importantly, we develop a novel method that can remove redundancy from the selected SNP panels and show that we can effectively remove correlated markers, thus increasing genotyping savings. Only 150-200 PCAIMs suffice to accurately predict fine structure in European American datasets, as identified by PCA. Simulating association studies, we couple our method with a PCA-based stratification correction tool and demonstrate that a small number of PCAIMs can efficiently remove false correlations with almost no loss in power. The structure informative SNPs that we propose are an important resource for genetic association studies of European Americans. Furthermore, our redundancy removal algorithm can be applied on sets of ancestry informative markers selected with any method in order to select the most uncorrelated SNPs, and significantly decreases genotyping costs.

  16. Estimating hidden population size using Respondent-Driven Sampling data.

    Science.gov (United States)

    Handcock, Mark S; Gile, Krista J; Mar, Corinne M

    Respondent-Driven Sampling (RDS) is n approach to sampling design and inference in hard-to-reach human populations. It is often used in situations where the target population is rare and/or stigmatized in the larger population, so that it is prohibitively expensive to contact them through the available frames. Common examples include injecting drug users, men who have sex with men, and female sex workers. Most analysis of RDS data has focused on estimating aggregate characteristics, such as disease prevalence. However, RDS is often conducted in settings where the population size is unknown and of great independent interest. This paper presents an approach to estimating the size of a target population based on data collected through RDS. The proposed approach uses a successive sampling approximation to RDS to leverage information in the ordered sequence of observed personal network sizes. The inference uses the Bayesian framework, allowing for the incorporation of prior knowledge. A flexible class of priors for the population size is used that aids elicitation. An extensive simulation study provides insight into the performance of the method for estimating population size under a broad range of conditions. A further study shows the approach also improves estimation of aggregate characteristics. Finally, the method demonstrates sensible results when used to estimate the size of known networked populations from the National Longitudinal Study of Adolescent Health, and when used to estimate the size of a hard-to-reach population at high risk for HIV.

  17. Quasi equilibrium, variance effective size and fixation index for populations with substructure.

    Science.gov (United States)

    Hössjer, Ola; Ryman, Nils

    2014-11-01

    In this paper, we develop a method for computing the variance effective size N eV, the fixation index F ST and the coefficient of gene differentiation G ST of a structured population under equilibrium conditions. The subpopulation sizes are constant in time, with migration and reproduction schemes that can be chosen with great flexibility. Our quasi equilibrium approach is conditional on non-fixation of alleles. This is of relevance when migration rates are of a larger order of magnitude than the mutation rates, so that new mutations can be ignored before equilibrium balance between genetic drift and migration is obtained. The vector valued time series of subpopulation allele frequencies is divided into two parts; one corresponding to genetic drift of the whole population and one corresponding to differences in allele frequencies among subpopulations. We give conditions under which the first two moments of the latter, after a simple standardization, are well approximated by quantities that can be explicitly calculated. This enables us to compute approximations of the quasi equilibrium values of N eV, F ST and G ST. Our findings are illustrated for several reproduction and migration scenarios, including the island model, stepping stone models and a model where one subpopulation acts as a demographic reservoir. We also make detailed comparisons with a backward approach based on coalescence probabilities.

  18. Probability Sampling Method for a Hidden Population Using Respondent-Driven Sampling: Simulation for Cancer Survivors.

    Science.gov (United States)

    Jung, Minsoo

    2015-01-01

    When there is no sampling frame within a certain group or the group is concerned that making its population public would bring social stigma, we say the population is hidden. It is difficult to approach this kind of population survey-methodologically because the response rate is low and its members are not quite honest with their responses when probability sampling is used. The only alternative known to address the problems caused by previous methods such as snowball sampling is respondent-driven sampling (RDS), which was developed by Heckathorn and his colleagues. RDS is based on a Markov chain, and uses the social network information of the respondent. This characteristic allows for probability sampling when we survey a hidden population. We verified through computer simulation whether RDS can be used on a hidden population of cancer survivors. According to the simulation results of this thesis, the chain-referral sampling of RDS tends to minimize as the sample gets bigger, and it becomes stabilized as the wave progresses. Therefore, it shows that the final sample information can be completely independent from the initial seeds if a certain level of sample size is secured even if the initial seeds were selected through convenient sampling. Thus, RDS can be considered as an alternative which can improve upon both key informant sampling and ethnographic surveys, and it needs to be utilized for various cases domestically as well.

  19. Parsing social network survey data from hidden populations using stochastic context-free grammars.

    Directory of Open Access Journals (Sweden)

    Art F Y Poon

    Full Text Available BACKGROUND: Human populations are structured by social networks, in which individuals tend to form relationships based on shared attributes. Certain attributes that are ambiguous, stigmatized or illegal can create a OhiddenO population, so-called because its members are difficult to identify. Many hidden populations are also at an elevated risk of exposure to infectious diseases. Consequently, public health agencies are presently adopting modern survey techniques that traverse social networks in hidden populations by soliciting individuals to recruit their peers, e.g., respondent-driven sampling (RDS. The concomitant accumulation of network-based epidemiological data, however, is rapidly outpacing the development of computational methods for analysis. Moreover, current analytical models rely on unrealistic assumptions, e.g., that the traversal of social networks can be modeled by a Markov chain rather than a branching process. METHODOLOGY/PRINCIPAL FINDINGS: Here, we develop a new methodology based on stochastic context-free grammars (SCFGs, which are well-suited to modeling tree-like structure of the RDS recruitment process. We apply this methodology to an RDS case study of injection drug users (IDUs in Tijuana, México, a hidden population at high risk of blood-borne and sexually-transmitted infections (i.e., HIV, hepatitis C virus, syphilis. Survey data were encoded as text strings that were parsed using our custom implementation of the inside-outside algorithm in a publicly-available software package (HyPhy, which uses either expectation maximization or direct optimization methods and permits constraints on model parameters for hypothesis testing. We identified significant latent variability in the recruitment process that violates assumptions of Markov chain-based methods for RDS analysis: firstly, IDUs tended to emulate the recruitment behavior of their own recruiter; and secondly, the recruitment of like peers (homophily was dependent on

  20. Thermal substructure of hot deformed austenite substructure

    Energy Technology Data Exchange (ETDEWEB)

    Bernshtejn, M.L.; Kaputkina, L.M.; Nikishov, N.A. (Moskovskij Inst. Stali i Splavov (USSR))

    1982-01-01

    Effect of hot working different regimes on formation of austenite structure and substructure of the 60N20 and 60Kh5G6 steels and kinetics of softening processes at postdeformation isothermal (at deformation temperature) heating, is investigated. It is shown, that variation of hot working regimes permits to obtain a wide range of structural and substructural austenite conditions. Rate decrease and temperature increase promotes obtaining after hot working and conservation under cooling conditions of developed polygonized substructure. Similar polygonized isotropic substructure with a rather low density of dislocations inside of subgrains promotes decelerating of initial stages of recrystallization development under conditions of hot working and regulated post-deformation heatings. Alloying by carbide-forming elements (chromium and manganese) delays development of recrystallization (in comparison with alloying with nickel), even if the steel is in the condition of single-phase solid solution.

  1. Using biomedical engineering and "hidden capital" to provide educational outreach to disadvantaged populations.

    Science.gov (United States)

    Drazan, John F; Scott, John M; Hoke, Jahkeen I; Ledet, Eric H

    2014-01-01

    A hands-on learning module called "Science of the Slam" is created that taps into the passions and interests of an under-represented group in the fields of Science, Technology, Engineering and Mathematics (STEM). This is achieved by examining the use of the scientific method to quantify the biomechanics of basketball players who are good at performing the slam dunk. Students already have an intrinsic understanding of the biomechanics of basketball however this "hidden capital" has never translated into the underlying STEM concepts. The effectiveness of the program is rooted in the exploitation of "hidden capital" within the field of athletics to inform and enhance athletic performance. This translation of STEM concepts to athletic performance provides a context and a motivation for students to study the STEM fields who are traditionally disengaged from the classic engineering outreach programs. "Science of the Slam" has the potential to serve as a framework for other researchers to engage under-represented groups in novel ways by tapping into shared interests between the researcher and disadvantaged populations.

  2. The Cluster Substructure - Alignment Connection

    OpenAIRE

    Plionis, Manolis

    2001-01-01

    Using the APM cluster data we investigate whether the dynamical status of clusters is related to the large-scale structure of the Universe. We find that cluster substructure is strongly correlated with the tendency of clusters to be aligned with their nearest neighbour and in general with the nearby clusters that belong to the same supercluster. Furthermore, dynamically young clusters are more clustered than the overall cluster population. These are strong indications that cluster develop in ...

  3. Health in the 'hidden population' of people with low literacy. A systematic review of the literature

    Directory of Open Access Journals (Sweden)

    Williams Brian

    2010-08-01

    Full Text Available Abstract Background Much of the evidence of an association between low functional or health literacy and poor health comes from studies that include people who have various cognitive difficulties or who do not speak the dominant language of their society. Low functional or health literacy among these people is likely to be evident in spoken conversation. However, many other people can talk readily about health and other issues but have problems using written information. Consequently, their difficulties may be far less evident to healthcare professionals, creating a 'hidden population' whose functional or health literacy problems have different implications because they are less likely to be recognised and addressed. We aimed to review published research to investigate relationships between low functional or health literacy and health in working age adults who can converse in the dominant language but have difficulty with written language. Methods We searched reviews and electronic databases for studies that examined health-related outcomes among the population of interest. We systematically extracted data relating to relationships between low functional or health literacy and both health status and various possible mediators or moderators of the implications of literacy for health. We developed a narrative review. Results Twenty-four studies met our inclusion criteria. Lower functional or health literacy in this population was found to be associated with worse health status. This may be mediated by difficulties accessing healthcare, and poorer self-management of health problems. It is currently unclear whether, how or to what extent these difficulties are mediated by poorer knowledge stemming from low functional or health literacy. The variation in functional or health literacy measures and comparisons make it difficult to compare study findings and to establish the implications of different literacy issues for health outcomes. Conclusions

  4. A Megacam Survey of Outer Halo Satellites. IV. Two foreground populations possibly associated with the Monoceros substructure in the direction of NGC2419 and Koposov2

    CERN Document Server

    Carballo-Bello, Julio A; Carlin, Jeffrey L; Cote, Patrick; Geha, Marla; Simon, Joshua D; Djorgovski, S G

    2015-01-01

    The origin of the Galactic halo stellar structure known as the Monoceros ring is still under debate. In this work, we study that halo substructure using deep CFHT wide-field photometry obtained for the globular clusters NGC2419 and Koposov2, where the presence of Monoceros becomes significant because of their coincident projected position. Using Sloan Digital Sky Survey photometry and spectroscopy in the area surrounding these globulars and beyond, where the same Monoceros population is detected, we conclude that a second feature, not likely to be associated with Milky Way disk stars along the line-of-sight, is present as foreground population. Our analysis suggests that the Monoceros ring might be composed of an old stellar population of age t ~ 9Gyr and a new component ~ 4Gyr younger at the same heliocentric distance. Alternatively, this detection might be associated with a second wrap of Monoceros in that direction of the sky and also indicate a metallicity spread in the ring. The detection of such a low-d...

  5. MtDNA control region variation affirms diversity and deep sub-structure in populations from southern Africa

    National Research Council Canada - National Science Library

    Schlebusch, Carina M; Lombard, Marlize; Soodyall, Himla

    2013-01-01

    The current San and Khoe populations are remnant groups of a much larger and widely dispersed population of hunter-gatherers and pastoralists, who had exclusive occupation of southern Africa before...

  6. Inspection of Asian Lacquer Substructures by Terahertz Time-Domain Imaging (THz-TDI)

    DEFF Research Database (Denmark)

    Dandolo, Corinna Ludovica Koch; Fukunaga, Kaori; Kohzuma, Yoshei;

    2016-01-01

    Lacquering is considered one of the most representative Asian artistic techniques. While the decorative part of lacquerwares is the lacquer itself, their substructures serve as the backbone of the object itself. Very little is known about these hidden substructures. Since lacquerwares are mostly ...

  7. Jet substructure in ATLAS

    CERN Document Server

    Miller, David W

    2011-01-01

    Measurements are presented of the jet invariant mass and substructure in proton-proton collisions at $\\sqrt{s} = 7$ TeV with the ATLAS detector using an integrated luminosity of 37 pb$^{-1}$. These results exercise the tools for distinguishing the signatures of new boosted massive particles in the hadronic final state. Two "fat" jet algorithms are used, along with the filtering jet grooming technique that was pioneered in ATLAS. New jet substructure observables are compared for the first time to data at the LHC. Finally, a sample of candidate boosted top quark events collected in the 2010 data is analyzed in detail for the jet substructure properties of hadronic "top-jets" in the final state. These measurements demonstrate not only our excellent understanding of QCD in a new energy regime but open the path to using complex jet substructure observables in the search for new physics.

  8. Jet Substructure Without Trees

    Energy Technology Data Exchange (ETDEWEB)

    Jankowiak, Martin; Larkoski, Andrew J.; /SLAC /Stanford U., ITP

    2011-08-19

    We present an alternative approach to identifying and characterizing jet substructure. An angular correlation function is introduced that can be used to extract angular and mass scales within a jet without reference to a clustering algorithm. This procedure gives rise to a number of useful jet observables. As an application, we construct a top quark tagging algorithm that is competitive with existing methods. In preparation for the LHC, the past several years have seen extensive work on various aspects of collider searches. With the excellent resolution of the ATLAS and CMS detectors as a catalyst, one area that has undergone significant development is jet substructure physics. The use of jet substructure techniques, which probe the fine-grained details of how energy is distributed in jets, has two broad goals. First, measuring more than just the bulk properties of jets allows for additional probes of QCD. For example, jet substructure measurements can be compared against precision perturbative QCD calculations or used to tune Monte Carlo event generators. Second, jet substructure allows for additional handles in event discrimination. These handles could play an important role at the LHC in discriminating between signal and background events in a wide variety of particle searches. For example, Monte Carlo studies indicate that jet substructure techniques allow for efficient reconstruction of boosted heavy objects such as the W{sup {+-}} and Z{sup 0} gauge bosons, the top quark, and the Higgs boson.

  9. Tagging Partially Reconstructed Objects with Jet Substructure

    CERN Document Server

    Freytsis, Marat; Walsh, Jonathan R

    2014-01-01

    We present a new tagger which aims at identifying partially reconstructed objects, in which only some of the constituents are collected in a single jet. As an example, we focus on top decays in which either part of the hadronically decaying W or the b jet is soft or falls outside of the top jet cone. We construct an observable to identify remnant substructure from the decay and employ aggressive jet grooming to reject QCD backgrounds. The tagger is complementary to existing ones and works well in the intermediate boost regime where jet substructure techniques usually fail. It is anticipated that a similar tagger can be used to identify non-QCD hadronic jets, such as those expected from hidden valleys.

  10. Jet Substructure by Accident

    CERN Document Server

    Cohen, Timothy; Lisanti, Mariangela; Lou, Hou Keong

    2012-01-01

    We propose a new search strategy for high-multiplicity hadronic final states. When new particles are produced at threshold, the distribution of their decay products is approximately isotropic. If there are many partons in the final state, it is likely that several will be clustered into the same large-radius jet. The resulting jet exhibits substructure, even though the parent states are not boosted. This "accidental" substructure is a powerful discriminant against background because it is more pronounced for high-multiplicity signals than for QCD multijets. We demonstrate how to take advantage of accidental substructure to reduce backgrounds without relying on the presence of missing energy. As an example, we present the expected limits for several R-parity violating gluino decay topologies. This approach allows for the determination of QCD backgrounds using data-driven methods, which is crucial for the feasibility of any search that targets signatures with many jets and suppressed missing energy.

  11. The population genomics of archaeological transition in west Iberia: Investigation of ancient substructure using imputation and haplotype-based methods.

    Science.gov (United States)

    Martiniano, Rui; Cassidy, Lara M; Ó'Maoldúin, Ros; McLaughlin, Russell; Silva, Nuno M; Manco, Licinio; Fidalgo, Daniel; Pereira, Tania; Coelho, Maria J; Serra, Miguel; Burger, Joachim; Parreira, Rui; Moran, Elena; Valera, Antonio C; Porfirio, Eduardo; Boaventura, Rui; Silva, Ana M; Bradley, Daniel G

    2017-07-01

    We analyse new genomic data (0.05-2.95x) from 14 ancient individuals from Portugal distributed from the Middle Neolithic (4200-3500 BC) to the Middle Bronze Age (1740-1430 BC) and impute genomewide diploid genotypes in these together with published ancient Eurasians. While discontinuity is evident in the transition to agriculture across the region, sensitive haplotype-based analyses suggest a significant degree of local hunter-gatherer contribution to later Iberian Neolithic populations. A more subtle genetic influx is also apparent in the Bronze Age, detectable from analyses including haplotype sharing with both ancient and modern genomes, D-statistics and Y-chromosome lineages. However, the limited nature of this introgression contrasts with the major Steppe migration turnovers within third Millennium northern Europe and echoes the survival of non-Indo-European language in Iberia. Changes in genomic estimates of individual height across Europe are also associated with these major cultural transitions, and ancestral components continue to correlate with modern differences in stature.

  12. The effect of a disc on the population of cuspy and cored dark matter substructures in Milky Way-like galaxies

    Science.gov (United States)

    Errani, Raphaël; Peñarrubia, Jorge; Laporte, Chervin F. P.; Gómez, Facundo A.

    2017-02-01

    We use high-resolution N-body simulations to study the effect of a galactic disc on the dynamical evolution of dark matter substructures with orbits and structural parameters extracted from the Aquarius A-2 merger tree. Satellites are modelled as equilibrium N-body realizations of generalized Hernquist profiles with 2 × 106 particles and injected in the analytical evolving host potential at zinfall, defined by the peak of their mass evolution. We select all substructures with M200(zinfall) ≥ 108 M⊙ and first pericentric distances rp values for all four models.

  13. The effect of a disc on the population of cuspy and cored dark matter substructures in Milky Way-like galaxies

    Science.gov (United States)

    Errani, Raphaël; Penarrubia, Jorge; Laporte, Chervin F. P.; Gomez, Facundo

    2017-06-01

    We use high-resolution N-body simulations to study the effect of a galactic disc on the dynamical evolution of dark matter substructures with orbits and structural parameters extracted from the Aquarius A-2 merger tree. Satellites are modelled as equilibrium N-body realizations of generalized Hernquist profiles with 2 × 106 particles and injected in the analytical evolving host potential at zinfall, defined by the peak of their mass evolution. We select all substructures with M200(zinfall) > 108 M⊙ and first pericentric distances rp < r200. Motivated by observations of Milky Way dwarf spheroidal galaxies, we also explore satellite models with cored dark matter profiles with a fixed core size rc = 0.8 as, where as is the Hernquist scale radius. We find that models with cuspy satellites have twice as many surviving substructures at z = 0 than their cored counterparts, and four times as many if we only consider those on orbits with rp < 0.1 r200. For a given profile, adding an evolving disc potential reduces the number of surviving substructures further by a factor of <2 for satellites on orbits which penetrate the disc (rp < 20 kpc). For large rp, where tidal forces and the effect of the disc become negligible, the number of satellites per pericentre bin converges to similar values for all four models.

  14. THE UNORTHODOX ORBITS OF SUBSTRUCTURE HALOS

    NARCIS (Netherlands)

    Ludlow, Aaron D.; Navarro, Julio F.; Springel, Volker; Jenkins, Adrian; Frenk, Carlos S.; Helmi, Amina

    2009-01-01

    We use a suite of cosmological N-body simulations to study the properties of substructure halos (subhalos) in galaxy-sized cold dark matter halos. We extend prior work on the subject by considering the whole population of subhalos physically associated with the main system. These are defined as subh

  15. Within-population genetic structure in beech (Fagus sylvatica L.) stands characterized by different disturbance histories: does forest management simplify population substructure?

    NARCIS (Netherlands)

    Piotti, A.; Leonardi, S.; Heuertz, M.; Buiteveld, J.; Geburek, T.; Gerber, S.; Kramer, K.; Vettori, C.; Vendramin, G.G.

    2013-01-01

    The fine-scale assessment of both spatially and non-spatially distributed genetic variation is crucial to preserve forest genetic resources through appropriate forest management. Cryptic within-population genetic structure may be more common than previously thought in forest tree populations, which

  16. Within-population genetic structure in beech (Fagus sylvatica L.) stands characterized by different disturbance histories: does forest management simplify population substructure?

    NARCIS (Netherlands)

    Piotti, A.; Leonardi, S.; Heuertz, M.; Buiteveld, J.; Geburek, T.; Gerber, S.; Kramer, K.; Vettori, C.; Vendramin, G.G.

    2013-01-01

    The fine-scale assessment of both spatially and non-spatially distributed genetic variation is crucial to preserve forest genetic resources through appropriate forest management. Cryptic within-population genetic structure may be more common than previously thought in forest tree populations, which

  17. The effect of a disc on the population of cuspy and cored dark matter substructures in Milky Way-like galaxies

    CERN Document Server

    Errani, Raphaël; Laporte, Chervin F P; Gómez, Facundo A

    2016-01-01

    We use high-resolution $N$-body simulations to study the effect of a galactic disc on the dynamical evolution of dark matter substructures with orbits and structural parameters extracted from the Aquarius A-2 merger tree (Springel et al. 2008). Satellites are modelled as equilibrium $N$-body realizations of generalized Hernquist profiles with $2\\times10^6$ particles and injected in the analytical evolving host potential at $z_\\mathrm{infall}$, defined by the peak of their mass evolution. We select all substructures with $M_{200}(z_\\mathrm{infall})\\geq 10^8\\,\\mathrm{M_\\odot}$ and first pericentric distances $r_psubstructures at $z=0$ than their cored counterparts, and four times as many if we only consider those on orb...

  18. Pre-elimination stage of malaria in Sri Lanka: assessing the level of hidden parasites in the population

    DEFF Research Database (Denmark)

    Rajakaruna, Rupika S; Alifrangis, Michael; Amerasinghe, Priyanie H

    2010-01-01

    to the process of complete elimination. The existence of a parasite reservoir in a population free from clinical manifestations, would influence the strategy for surveillance and control towards complete elimination. METHODS: The prevalence of hidden parasite reservoirs in two historically malaria endemic...... districts, Anuradhapura and Kurunegala, previously considered as high malaria transmission areas in Sri Lanka, where peaks of transmission follow the rainy seasons was assessed. Blood samples of non-febrile individuals aged five to 55 years were collected from randomly selected areas in the two districts...... participated from both districts comprising mostly adults between the ages 19-55 years. Out of these, only about 1.4% of them (n = 19) could recall having had malaria during the past five years. Analysis of a subset of samples (n = 1322) from the two districts using PCR showed that none of the participants had...

  19. Review of sampling hard-to-reach and hidden populations for HIV surveillance.

    Science.gov (United States)

    Magnani, Robert; Sabin, Keith; Saidel, Tobi; Heckathorn, Douglas

    2005-05-01

    Adequate surveillance of hard-to-reach and 'hidden' subpopulations is crucial to containing the HIV epidemic in low prevalence settings and in slowing the rate of transmission in high prevalence settings. For a variety of reasons, however, conventional facility and survey-based surveillance data collection strategies are ineffective for a number of key subpopulations, particularly those whose behaviors are illegal or illicit. This paper critically reviews alternative sampling strategies for undertaking behavioral or biological surveillance surveys of such groups. Non-probability sampling approaches such as facility-based sentinel surveillance and snowball sampling are the simplest to carry out, but are subject to a high risk of sampling/selection bias. Most of the probability sampling methods considered are limited in that they are adequate only under certain circumstances and for some groups. One relatively new method, respondent-driven sampling, an adaptation of chain-referral sampling, appears to be the most promising for general applications. However, as its applicability to HIV surveillance in resource-poor settings has yet to be established, further field trials are needed before a firm conclusion can be reached.

  20. Reactive attachment disorder in the general population: a hidden ESSENCE disorder.

    Science.gov (United States)

    Pritchett, Rachel; Pritchett, Jennifer; Marshall, Emma; Davidson, Claire; Minnis, Helen

    2013-01-01

    Reactive attachment disorder (RAD) is a severe disorder of social functioning. Previous research has shown that children with RAD may have poor cognitive and language abilities; however, findings mainly come from biased, institutionalised samples. This paper describes the characteristics of all children who were given a suspected or likely diagnosis of reactive attachment disorder in an epidemiological study of approximately 1,600 children investigating the prevalence of RAD in the general population. We found that children with RAD are more likely to have multiple comorbidities with other disorders, lower IQs than population norms, more disorganised attachment, more problem behaviours, and poorer social skills than would be found in the general population and therefore have a complex presentation than can be described as ESSENCE. We discuss the clinical and educational implications.

  1. Reactive Attachment Disorder in the General Population: A Hidden ESSENCE Disorder

    Directory of Open Access Journals (Sweden)

    Rachel Pritchett

    2013-01-01

    Full Text Available Reactive attachment disorder (RAD is a severe disorder of social functioning. Previous research has shown that children with RAD may have poor cognitive and language abilities; however, findings mainly come from biased, institutionalised samples. This paper describes the characteristics of all children who were given a suspected or likely diagnosis of reactive attachment disorder in an epidemiological study of approximately 1,600 children investigating the prevalence of RAD in the general population. We found that children with RAD are more likely to have multiple comorbidities with other disorders, lower IQs than population norms, more disorganised attachment, more problem behaviours, and poorer social skills than would be found in the general population and therefore have a complex presentation than can be described as ESSENCE. We discuss the clinical and educational implications.

  2. Inspection of Asian Lacquer Substructures by Terahertz Time-Domain Imaging (THz-TDI)

    Science.gov (United States)

    Dandolo, Corinna Ludovica Koch; Fukunaga, Kaori; Kohzuma, Yoshei; Kiriyama, Kyoko; Matsuda, Kazutaka; Jepsen, Peter Uhd

    2017-04-01

    Lacquering is considered one of the most representative Asian artistic techniques. While the decorative part of lacquerwares is the lacquer itself, their substructures serve as the backbone of the object itself. Very little is known about these hidden substructures. Since lacquerwares are mostly composed of organic materials, such as urushi, wood, carbon black, and fabrics which are very X-ray transparent, standard X-ray radiography has some problems in achieving clear X-ray radiographic images. Therefore, we wanted to contribute to the understanding of the lacquer manufacturing technique by inspecting the substructures of Asian lacquerwares by means of THz time-domain imaging (THz-TDI). Three different kinds of Asian lacquerwares were examined by THz-TDI, and the outcomes have been compared with those obtained by standard X-radiography. THz-TDI provides unique information on lacquerwares substructures, aiding in the comprehension of the manufacturing technology yielding to these precious artefacts.

  3. A Hidden Population of Massive Stars with Circumstellar Shells Discovered with the Spitzer Space Telescope

    CERN Document Server

    Wachter, S; Van Dyk, S D; Hoard, D W; Kafka, S; Morris, P W

    2010-01-01

    We have discovered a large number of circular and elliptical shells at 24 microns around luminous central sources with the MIPS instrument on-board the Spitzer Space Telescope. Our archival follow-up effort has revealed 90% of these circumstellar shells to be previously unknown. The majority of the shells is only visible at 24 microns, but many of the central stars are detected at multiple wavelengths from the mid- to the near-IR regime. The general lack of optical counterparts, however, indicates that these sources represent a population of highly obscured objects. We obtained optical and near-IR spectroscopic observations of the central stars and find most of these objects to be massive stars. In particular, we identify a large population of sources that we argue represents a narrow evolutionary phase, closely related or identical to the LBV stage of massive stellar evolution.

  4. Hidden leprosy cases in tribal population groups and how to reach them through a collaborative effort.

    Science.gov (United States)

    Kumar, M Santhosh; Padmavathi, S; Shivakumar, M; Charles, U; Appalanaidu, M; Perumal, R; Thiagarajan, P N; Somasekhar, Y

    2015-12-01

    Tribal populations are an underserved population group and access to health services is a major challenge for them. Since leprosy treatment is integrated with the general health services, identifying leprosy cases is not be easy in these settings and they remain as endemic reservoirs, unless greater efforts are made to reach them. An active search operation was conducted in the tribal colonies in four pre-identified Health & Nutrition Clusters, Nellore district, Andhra Pradesh, India, in 2013. After a brief training, village health nurses and selected volunteers covered all the households, showing flash cards with photos of leprosy cases and enquiring if there was any resident with a similar condition. Suspects were listed and examined by the district leprosy supervisor and field coordinators from Damien Foundation. Follow up interviews were done after one year to assess the treatment completion rate. Village health workers covered 47,574 people living in the tribal colonies and identified 325 leprosy suspects. Among them, 70 were confirmed as new leprosy cases. The prevalence of previously undetected leprosy cases was found to be 14.7/10,000. Out of 70 cases, 19 (27%) were children, 35 (50%) were female, 32 (45.7%) were classified as MB leprosy, 6 (8.6%) had a leprosy reaction and 11 (15.7%) persons had Grade 2 disability at the time of diagnosis. The treatment completion rate was found to be 74% at the end of one year. The study reveals a very high burden of leprosy among the tribal population and demonstrates how resources can be mobilized from government, NGO and local community sources to promote early case detection among underserved population groups.

  5. Predictions of native American population structure using linguistic covariates in a hidden regression framework.

    Directory of Open Access Journals (Sweden)

    Flora Jay

    Full Text Available BACKGROUND: The mainland of the Americas is home to a remarkable diversity of languages, and the relationships between genes and languages have attracted considerable attention in the past. Here we investigate to which extent geography and languages can predict the genetic structure of Native American populations. METHODOLOGY/PRINCIPAL FINDINGS: Our approach is based on a Bayesian latent cluster regression model in which cluster membership is explained by geographic and linguistic covariates. After correcting for geographic effects, we find that the inclusion of linguistic information improves the prediction of individual membership to genetic clusters. We further compare the predictive power of Greenberg's and The Ethnologue classifications of Amerindian languages. We report that The Ethnologue classification provides a better genetic proxy than Greenberg's classification at the stock and at the group levels. Although high predictive values can be achieved from The Ethnologue classification, we nevertheless emphasize that Choco, Chibchan and Tupi linguistic families do not exhibit a univocal correspondence with genetic clusters. CONCLUSIONS/SIGNIFICANCE: The Bayesian latent class regression model described here is efficient at predicting population genetic structure using geographic and linguistic information in Native American populations.

  6. The genetics of amphibian decline: population substructure and molecular differentiation in the Yosemite toad, Bufo canorus (Anura, Bufonidae) based on single-strand conformation polymorphism analysis (SSCP) and mitochondrial DNA sequence data

    Science.gov (United States)

    Shaffer, H. Bradley; Fellers, Gary M.; Magee, Allison; Voss, S. Randal

    2000-01-01

    We present a comprehensive survey of genetic variation across the range of the narrowly distributed endemic Yosemite toad Bufo canorus, a declining amphibian restricted to the Sierra Nevada of California. Based on 322 bp of mitochondrial cytochrome b sequence data, we found limited support for the monophyly of B. canorus and its closely related congener B. exsul to the exclusion of the widespread western toad B. boreas. However, B. exsul was always phylogenetically nested within B. canorus, suggesting that the latter may not be monophyletic. SSCP (single-strand conformation polymorphism) analysis of 372 individual B. canorus from 28 localities in Yosemite and Kings Canyon National Parks revealed no shared haplotypes among these two regions and lead us to interpret these two parks as distinct management units for B. canorus. Within Yosemite, we found significant genetic substructure both at the level of major drainages and among breeding ponds. Kings Canyon samples show a different pattern, with substantial variation among breeding sites, but no substructure among drainages. Across the range of B. canorus as well as among Yosemite ponds, we found an isolation-by-distance pattern suggestive of a stepping stone model of migration. However, in Kings Canyon we found no hint of such a pattern, suggesting that movement patterns of toads may be quite different in these nearby parklands. Our data imply that management for B. canorus should focus at the individual pond level, and effective management may necessitate reintroductions if local extirpations occur. A brief review of other pond-breeding anurans suggests that highly structured populations are often the case, and thus that our results for B. canorus may be general for other species of frogs and toads.

  7. Early dynamical evolution of young substructured clusters

    Science.gov (United States)

    Dorval, Julien; Boily, Christian

    2017-03-01

    Stellar clusters form with a high level of substructure, inherited from the molecular cloud and the star formation process. Evidence from observations and simulations also indicate the stars in such young clusters form a subvirial system. The subsequent dynamical evolution can cause important mass loss, ejecting a large part of the birth population in the field. It can also imprint the stellar population and still be inferred from observations of evolved clusters. Nbody simulations allow a better understanding of these early twists and turns, given realistic initial conditions. Nowadays, substructured, clumpy young clusters are usually obtained through pseudo-fractal growth and velocity inheritance. We introduce a new way to create clumpy initial conditions through a ''Hubble expansion'' which naturally produces self consistent clumps, velocity-wise. In depth analysis of the resulting clumps shows consistency with hydrodynamical simulations of young star clusters. We use these initial conditions to investigate the dynamical evolution of young subvirial clusters. We find the collapse to be soft, with hierarchical merging leading to a high level of mass segregation. The subsequent evolution is less pronounced than the equilibrium achieved from a cold collapse formation scenario.

  8. The Unorthodox Orbits of Substructure Halos

    CERN Document Server

    Ludlow, Aaron D; Springel, Volker; Jenkins, Adrian; Frenk, Carlos S; Helmi, Amina

    2008-01-01

    We use numerical simulations to study the properties of substructure within galaxy-sized dark matter halos. Our study extends previous work by considering the whole population of subhalos physically associated with the main system; these are subhalos that have at some time been within the virial radius of the main progenitor and have survived as self-bound entities to z=0. We find that this population extends beyond three times the virial radius and contains objects on extreme orbits. We trace the origin of these unorthodox orbits to multiple-body interactions acting during the tidal dissociation of bound groups. Multiple-body interactions affect primarily low-mass subhalos and push them onto higher energy orbits, resulting in a strong mass-dependent bias in the spatial distribution and kinematics of associated subhalos: the lower the subhalo mass at accretion time, the less concentrated and kinematically hotter their descendant population. Our findings imply that subhalos identified within the virial radius ...

  9. Cold Dark Matter Substructure and Galactic Disks

    CERN Document Server

    Kazantzidis, Stelios; Bullock, James S

    2008-01-01

    We perform a set of high-resolution, dissipationless N-body simulations to investigate the influence of cold dark matter (CDM) substructure on the dynamical evolution of thin galactic disks. Our method combines cosmological simulations of galaxy-sized CDM halos to derive the properties of substructure populations and controlled numerical experiments of consecutive subhalo impacts onto initially-thin, fully-formed disk galaxies. We demonstrate that close encounters between massive subhalos and galactic disks since z~1 should be common occurrences in LCDM models. In contrast, extremely few satellites in present-day CDM halos are likely to have a significant impact on the disk structure. One typical host halo merger history is used to seed controlled N-body experiments of subhalo-disk encounters. As a result of these accretion events, the disk thickens considerably at all radii with the disk scale height increasing in excess of a factor of 2 in the solar neighborhood. We show that interactions with the subhalo p...

  10. Substructure mining using elaborate chemical representation.

    Science.gov (United States)

    Kazius, Jeroen; Nijssen, Siegfried; Kok, Joost; Bäck, Thomas; Ijzerman, Adriaan P

    2006-01-01

    Substructure mining algorithms are important drug discovery tools since they can find substructures that affect physicochemical and biological properties. Current methods, however, only consider a part of all chemical information that is present within a data set of compounds. Therefore, the overall aim of our study was to enable more exhaustive data mining by designing methods that detect all substructures of any size, shape, and level of chemical detail. A means of chemical representation was developed that uses atomic hierarchies, thus enabling substructure mining to consider general and/or highly specific features. As a proof-of-concept, the efficient, multipurpose graph mining system Gaston learned substructures of any size and shape from a mutagenicity data set that was represented in this manner. From these substructures, we extracted a set of only six nonredundant, discriminative substructures that represent relevant biochemical knowledge. Our results demonstrate the individual and synergistic importance of elaborate chemical representation and mining for nonlinear substructures. We conclude that the combination of elaborate chemical representation and Gaston provides an excellent method for 2D substructure mining as this recipe systematically explores all substructures in different levels of chemical detail.

  11. Chemical substructure analysis in toxicology

    Energy Technology Data Exchange (ETDEWEB)

    Beauchamp, R.O. Jr. [Center for Information on Toxicology and Environment, Raleigh, NC (United States)

    1990-12-31

    A preliminary examination of chemical-substructure analysis (CSA) demonstrates the effective use of the Chemical Abstracts compound connectivity file in conjunction with the bibliographic file for relating chemical structures to biological activity. The importance of considering the role of metabolic intermediates under a variety of conditions is illustrated, suggesting structures that should be examined that may exhibit potential activity. This CSA technique, which utilizes existing large files accessible with online personal computers, is recommended for use as another tool in examining chemicals in drugs. 2 refs., 4 figs.

  12. Hidden loss

    DEFF Research Database (Denmark)

    Kieffer-Kristensen, Rikke; Johansen, Karen Lise Gaardsvig

    2013-01-01

    to participate. RESULTS: All children were affected by their parents' ABI and the altered family situation. The children's expressions led the authors to identify six themes, including fear of losing the parent, distress and estrangement, chores and responsibilities, hidden loss, coping and support. The main...... the ill parent. These findings contribute to a deeper understanding of the traumatic process of parental ABI that some children experience and emphasize the importance of family-centred interventions that include the children....

  13. Mass Substructure in Abell 3128

    Science.gov (United States)

    McCleary, J.; dell'Antonio, I.; Huwe, P.

    2015-05-01

    We perform a detailed two-dimensional weak gravitational lensing analysis of the nearby (z = 0.058) galaxy cluster Abell 3128 using deep ugrz imaging from the Dark Energy Camera (DECam). We have designed a pipeline to remove instrumental artifacts from DECam images and stack multiple dithered observations without inducing a spurious ellipticity signal. We develop a new technique to characterize the spatial variation of the point-spread function that enables us to circularize the field to better than 0.5% and thereby extract the intrinsic galaxy ellipticities. By fitting photometric redshifts to sources in the observation, we are able to select a sample of background galaxies for weak-lensing analysis free from low-redshift contaminants. Photometric redshifts are also used to select a high-redshift galaxy subsample with which we successfully isolate the signal from an interloping z = 0.44 cluster. We estimate the total mass of Abell 3128 by fitting the tangential ellipticity of background galaxies with the weak-lensing shear profile of a Navarro-Frenk-White (NFW) halo and also perform NFW fits to substructures detected in the 2D mass maps of the cluster. This study yields one of the highest resolution mass maps of a low-z cluster to date and is the first step in a larger effort to characterize the redshift evolution of mass substructures in clusters.

  14. MASS SUBSTRUCTURE IN ABELL 3128

    Energy Technology Data Exchange (ETDEWEB)

    McCleary, J.; Dell’Antonio, I.; Huwe, P., E-mail: Jacqueline_McCleary@brown.edu [Department of Physics, Brown University, Box 1843, Providence, RI 02912 (United States)

    2015-05-20

    We perform a detailed two-dimensional weak gravitational lensing analysis of the nearby (z = 0.058) galaxy cluster Abell 3128 using deep ugrz imaging from the Dark Energy Camera (DECam). We have designed a pipeline to remove instrumental artifacts from DECam images and stack multiple dithered observations without inducing a spurious ellipticity signal. We develop a new technique to characterize the spatial variation of the point-spread function that enables us to circularize the field to better than 0.5% and thereby extract the intrinsic galaxy ellipticities. By fitting photometric redshifts to sources in the observation, we are able to select a sample of background galaxies for weak-lensing analysis free from low-redshift contaminants. Photometric redshifts are also used to select a high-redshift galaxy subsample with which we successfully isolate the signal from an interloping z = 0.44 cluster. We estimate the total mass of Abell 3128 by fitting the tangential ellipticity of background galaxies with the weak-lensing shear profile of a Navarro–Frenk–White (NFW) halo and also perform NFW fits to substructures detected in the 2D mass maps of the cluster. This study yields one of the highest resolution mass maps of a low-z cluster to date and is the first step in a larger effort to characterize the redshift evolution of mass substructures in clusters.

  15. Jet substructure measurements at ATLAS and CMS

    CERN Document Server

    Dattagupta, Aparajita; The ATLAS collaboration

    2017-01-01

    A review is given of recent Run II measurements of jet substructure at CMS and ATLAS, as well of the most relevant measurements from Run I. Quark and gluon discrimination, jet mass and other substructure observable are discussed together with prospects for future measurements with new insight from theory.

  16. Optical Substructures in 48 Galaxy Clusters

    CERN Document Server

    Girardi, M; Fadda, D; Giuricin, G; Mardirossian, F; Mezzetti, M

    1996-01-01

    We analyze the presence of substructures in a set of 48 galaxy clusters, by using galaxy positions and redshifts. We use a multi-scale analysis which couples kinematical estimators with the wavelet transform. 14% of our clusters are strongly substructured (i.e. they are bimodal or complex) and 24% of the remaining unimodal clusters contain substructures at small scales. Thus, in substantial agreement with previous studies, about one third of clusters show substructures. In unimodal clusters the presence of substructures does not affect the estimates of both virial masses and velocity dispersions, which are generally in good agreement with the X-ray temperatures. Thus, unimodal clusters are not too far from a status of dynamical equilibrium. On the contrary, velocity dispersions and masses for some bimodal or complex clusters strongly depend on whether they are treated as single systems or as sums of different clumps and X-ray temperatures and velocity dispersions may be very different.

  17. Evolution variable dependence of jet substructure

    CERN Document Server

    Sakaki, Yasuhito

    2015-01-01

    Studies on jet substructure have evolved significantly in recent years. Jet substructure is essentially determined by QCD radiations and non-perturbative effects. Predictions of jet substructure are usually different among Monte Carlo event generators, and are governed by the parton shower algorithm implemented. For leading logarithmic parton shower, even though one of the core variables is the evolution variable, its choice is not unique. We examine evolution variable dependence of the jet substructure by developing a parton shower generator that interpolates between different evolution variables using a parameter $\\alpha$. Jet shape variables and associated jet rates for quark and gluon jets are used to demonstrate the $\\alpha$-dependence of the jet substructure. We find angular ordered shower predicts wider jets, while relative transverse momentum ($p_{\\bot}$) ordered shower predicts narrower jets. This is qualitatively in agreement with the missing phase space of $p_{\\bot}$ ordered showers. Such differenc...

  18. Analysis and application of European genetic substructure using 300 K SNP information.

    Directory of Open Access Journals (Sweden)

    Chao Tian

    2008-01-01

    Full Text Available European population genetic substructure was examined in a diverse set of >1,000 individuals of European descent, each genotyped with >300 K SNPs. Both STRUCTURE and principal component analyses (PCA showed the largest division/principal component (PC differentiated northern from southern European ancestry. A second PC further separated Italian, Spanish, and Greek individuals from those of Ashkenazi Jewish ancestry as well as distinguishing among northern European populations. In separate analyses of northern European participants other substructure relationships were discerned showing a west to east gradient. Application of this substructure information was critical in examining a real dataset in whole genome association (WGA analyses for rheumatoid arthritis in European Americans to reduce false positive signals. In addition, two sets of European substructure ancestry informative markers (ESAIMs were identified that provide substantial substructure information. The results provide further insight into European population genetic substructure and show that this information can be used for improving error rates in association testing of candidate genes and in replication studies of WGA scans.

  19. Type Classes for Lightweight Substructural Types

    Directory of Open Access Journals (Sweden)

    Edward Gan

    2015-02-01

    Full Text Available Linear and substructural types are powerful tools, but adding them to standard functional programming languages often means introducing extra annotations and typing machinery. We propose a lightweight substructural type system design that recasts the structural rules of weakening and contraction as type classes; we demonstrate this design in a prototype language, Clamp. Clamp supports polymorphic substructural types as well as an expressive system of mutable references. At the same time, it adds little additional overhead to a standard Damas-Hindley-Milner type system enriched with type classes. We have established type safety for the core model and implemented a type checker with type inference in Haskell.

  20. Estimating Divergence Time and Ancestral Effective Population Size of Bornean and Sumatran Orangutan Subspecies Using a Coalescent Hidden Markov Model

    DEFF Research Database (Denmark)

    Mailund, Thomas; Dutheil, Julien; Hobolth, Asger

    2011-01-01

    event has occurred to split them apart. The size of these segments of constant divergence depends on the recombination rate, but also on the speciation time, the effective population size of the ancestral population, as well as demographic effects and selection. Thus, inference of these parameters may......ue to genetic variation in the ancestor of two populations or two species, the divergence time for DNA sequences from two populations is variable along the genome. Within genomic segments all bases will share the same divergence—because they share a most recent common ancestor—when no recombination...

  1. A Bell-type Theorem Without Hidden Variables

    CERN Document Server

    Stapp, Henry P

    2002-01-01

    Bell's theorem rules out local hidden-variable theories. The locality condition is the demand that what an experimenter freely chooses to measure in one space-time region has no influence in a second space-time region that is spacelike separated from the first. The hidden-variable stipulation means that this demand is implemented through requirements on an assumed-to-exist substructure involving hidden variables. The question thus arises whether the locality condition itself fails, or only its implementation by means of the assumed hidden-variable structure. This paper shows that any theory that satisfies two generally accepted features of orthodox quantum theory and that yields certain predictions of quantum theory cannot satisfy the afore-mentioned locality condition. These two features are that the choices made by the experimenters can be treated as localized free variables and that such free choices do not affect outcomes that have already occurred.

  2. A Hidden Markov Model to estimate population mixture and allelic copy-numbers in cancers using Affymetrix SNP arrays

    Directory of Open Access Journals (Sweden)

    Torring Niels

    2007-11-01

    Full Text Available Abstract Background Affymetrix SNP arrays can interrogate thousands of SNPs at the same time. This allows us to look at the genomic content of cancer cells and to investigate the underlying events leading to cancer. Genomic copy-numbers are today routinely derived from SNP array data, but the proposed algorithms for this task most often disregard the genotype information available from germline cells in paired germline-tumour samples. Including this information may deepen our understanding of the "true" biological situation e.g. by enabling analysis of allele specific copy-numbers. Here we rely on matched germline-tumour samples and have developed a Hidden Markov Model (HMM to estimate allelic copy-number changes in tumour cells. Further with this approach we are able to estimate the proportion of normal cells in the tumour (mixture proportion. Results We show that our method is able to recover the underlying copy-number changes in simulated data sets with high accuracy (above 97.71%. Moreover, although the known copy-numbers could be well recovered in simulated cancer samples with more than 70% cancer cells (and less than 30% normal cells, we demonstrate that including the mixture proportion in the HMM increases the accuracy of the method. Finally, the method is tested on HapMap samples and on bladder and prostate cancer samples. Conclusion The HMM method developed here uses the genotype calls of germline DNA and the allelic SNP intensities from the tumour DNA to estimate allelic copy-numbers (including changes in the tumour. It differentiates between different events like uniparental disomy and allelic imbalances. Moreover, the HMM can estimate the mixture proportion, and thus inform about the purity of the tumour sample.

  3. Chemical substructure search in SQL.

    Science.gov (United States)

    Golovin, Adel; Henrick, Kim

    2009-01-01

    We present a novel technique for a fast chemical substructure search on a relational database by use of a standard SQL query. The symmetry of a query graph is analyzed to give additional constraints. Our method is based on breadth-first search (BFS) algorithms implementation using Relational Database Management Systems (RDBMS). In addition to the chemical search we apply our technique to the field of intermolecular interactions which involves nonplanar graphs and describe how to achieve linear time performance along with the suggestion on how to sufficiently reduce the linear coefficient. From the algorithms theory perspective these results mean that subgraph isomorphism is a polynomial time problem, hence equal problems have the same complexity. The application to subgraph isomorphism in chemical search is available at http://www.ebi.ac.uk/msd-srv/chemsearch and http://www.ebi.ac.uk/msd-srv/msdmotif/chem . The application to the network of molecule interactions is available at http://www.ebi.ac.uk/msd-srv/msdmotif .

  4. Algebraic sub-structuring for electromagnetic applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chao; Gao, Weiguo; Bai, Zhaojun; Li, Xiaoye; Lee, Lie-Quan; Husbands, Parry; Ng, Esmond G.

    2004-09-14

    Algebraic sub-structuring refers to the process of applying matrix reordering and partitioning algorithms to divide a large sparse matrix into smaller submatrices from which a subset of spectral components are extracted and combined to form approximate solutions to the original problem. In this paper, we show that algebraic sub-structuring can be effectively used to solve generalized eigenvalue problems arising from the finite element analysis of an accelerator structure.

  5. Algebraic Sub-Structuring for Electromagnetic Applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang, C.; Gao, W.G.; Bai, Z.J.; Li, X.Y.S.; Lee, L.Q.; Husbands, P.; Ng, E.G.; /LBL, Berkeley /UC, Davis /SLAC

    2006-06-30

    Algebraic sub-structuring refers to the process of applying matrix reordering and partitioning algorithms to divide a large sparse matrix into smaller submatrices from which a subset of spectral components are extracted and combined to form approximate solutions to the original problem. In this paper, they show that algebraic sub-structuring can be effectively used to solve generalized eigenvalue problems arising from the finite element analysis of an accelerator structure.

  6. A structural design decomposition method utilizing substructuring

    Science.gov (United States)

    Scotti, Stephen J.

    1994-01-01

    A new method of design decomposition for structural analysis and optimization is described. For this method, the structure is divided into substructures where each substructure has its structural response described by a structural-response subproblem, and its structural sizing determined from a structural-sizing subproblem. The structural responses of substructures that have rigid body modes when separated from the remainder of the structure are further decomposed into displacements that have no rigid body components, and a set of rigid body modes. The structural-response subproblems are linked together through forces determined within a structural-sizing coordination subproblem which also determines the magnitude of any rigid body displacements. Structural-sizing subproblems having constraints local to the substructures are linked together through penalty terms that are determined by a structural-sizing coordination subproblem. All the substructure structural-response subproblems are totally decoupled from each other, as are all the substructure structural-sizing subproblems, thus there is significant potential for use of parallel solution methods for these subproblems.

  7. SU Lyncis, a Hard X-Ray Bright M Giant: Clues Point to a Large Hidden Population of Symbiotic Stars

    Science.gov (United States)

    Mukai, K.; Luna, G. J. M.; Cusumano, G.; Segreto, A.; Munari, U.; Sokoloski, J. L.; Lucy, A. B.; Nelson, T.; Nunez, N. E.

    2016-01-01

    Symbiotic star surveys have traditionally relied almost exclusively on low resolution optical spectroscopy. However, we can obtain amore reliable estimate of their total Galactic population by using all available signatures of the symbiotic phenomenon. Here we report the discovery of a hard X-ray source, 4PBC J0642.9+5528, in the Swift hard X-ray all-sky survey, and identify it with a poorly studied red giant, SU Lyn, using pointed Swift observations and ground-based optical spectroscopy. The X-ray spectrum, the optical to UV spectrum, and the rapid UV variability of SU Lyn are all consistent with our interpretation that it is a symbiotic star containing an accreting white dwarf. The symbiotic nature of SU Lyn went unnoticed until now, because it does not exhibit emission lines strong enough to be obvious in low resolution spectra. We argue that symbiotic stars without shell-burning have weak emission lines, and that the current lists of symbiotic stars are biased in favour of shell-burning systems. We conclude that the true population of symbiotic stars has been underestimated, potentially by a large factor.

  8. The Singular Behavior of Jet Substructure Observables

    CERN Document Server

    Larkoski, Andrew J

    2016-01-01

    Jet substructure observables play a central role at the Large Hadron Collider for identifying the boosted hadronic decay products of electroweak scale resonances. The complete description of these observables requires understanding both the limit in which hard substructure is resolved, as well as the limit of a jet with a single hard core. In this paper we study in detail the perturbative structure of two prominent jet substructure observables, $N$-subjettiness and the energy correlation functions, as measured on background QCD jets. In particular, we focus on the distinction between the limits in which two-prong structure is resolved or unresolved. Depending on the choice of subjet axes, we demonstrate that at fixed order, $N$-subjettiness can manifest myriad behaviors in the unresolved region: smooth tails, end-point singularities, or singularities in the physical region. The energy correlation functions, by contrast, only have non-singular perturbative tails extending to the end point. We discuss the effec...

  9. A Comparison of Internet-Based Participant Recruitment Methods: Engaging the Hidden Population of Cannabis Users in Research

    Directory of Open Access Journals (Sweden)

    Elizabeth Clare Temple

    2011-01-01

    Full Text Available While a growing number of researchers are embracing Internet-based data collection methods, the adoption of Internet-based recruitment methods has been relatively slow. This may be because little is known regarding the relative strengths and weaknesses of different methods of Internet-based participant recruitment, nor how these different recruitment strategies impact on the data collected. These issues are addressed in this article with reference to a study comparing the effectiveness of three Internet-based strategies in recruiting cannabis users for an online study. Consideration of the recruitment data leads us to recommend that researchers use multipronged Internet-based recruitment campaigns with appropriately detailed recruitment messages tailored to the population of interest and located carefully to ensure they reach the intended audience. Further, we suggest that building rapport directly with potential participants, or utilising derived rapport and implicit endorsements, is an important aspect of successful Internet-based participant recruitment strategies.

  10. SU Lyncis, a hard X-ray bright M giant: Clues point to a large hidden population of symbiotic stars

    CERN Document Server

    Mukai, K; Cusumano, G; Segreto, A; Munari, U; Sokoloski, J L; Lucy, A B; Nelson, T; Nunez, N E

    2016-01-01

    Symbiotic star surveys have traditionally relied almost exclusively on low resolution optical spectroscopy. However, we can obtain a more reliable estimate of their total Galactic population by using all available signatures of the symbiotic phenomenon. Here we report the discovery of a hard X-ray source, 4PBC J0642.9+5528, in the Swift hard X-ray all-sky survey, and identify it with a poorly studied red giant, SU Lyn, using pointed Swift observations and ground-based optical spectroscopy. The X-ray spectrum, the optical to UV spectrum, and the rapid UV variability of SU Lyn are all consistent with our interpretation that it is a symbiotic star containing an accreting white dwarf. The symbiotic nature of SU Lyn went unnoticed until now, because it does not exhibit emission lines strong enough to be obvious in low resolution spectra. We argue that symbiotic stars without shell-burning have weak emission lines, and that the current lists of symbiotic stars are biased in favor of shell-burning systems. We conclu...

  11. Halo Substructure Towards the Galactic Center

    Science.gov (United States)

    Amy, Paul Martin; Martin, Charles; Newberg, Heidi Jo; Shelton, Siddartha; Carlin, Jeffrey L.; Willett, Benjamin A.

    2017-01-01

    We measure the velocity substructure of blue horizontal branch stars in Data Release 10 of the Sloan Digital Sky Survey, particularly in the regions of the Hermus Stream, the Hyllus Stream, and the Hercules-Aquila Cloud. These stars are concentrated at lower latitudes (b Research.

  12. MAPPING THE GALACTIC HALO. VIII. QUANTIFYING SUBSTRUCTURE

    NARCIS (Netherlands)

    Starkenburg, Else; Helmi, Amina; Morrison, Heather L.; Harding, Paul; van Woerden, Hugo; Mateo, Mario; Olszewski, Edward W.; Sivarani, Thirupathi; Norris, John E.; Freeman, Kenneth C.; Shectman, Stephen A.; Dohm-Palmer, R. C.; Frey, Lucy; Oravetz, Dan

    2009-01-01

    We have measured the amount of kinematic substructure in the Galactic halo using the final data set from the Spaghetti project, a pencil-beam high-latitude sky survey. Our sample contains 101 photometrically selected and spectroscopically confirmed giants with accurate distance, radial velocity, and

  13. Boosted objects and jet substructure at the LHC

    CERN Document Server

    Altheimer, A.; Asquith, L.; Backus Mayes, J.; Bergeaas Kuutmann, E.; Berger, J.; Bjergaard, D.; Bryngemark, L.; Buckley, A.; Butterworth, J.; Cacciari, M.; Campanelli, M.; Carli, T.; Chala, M.; Chen, C.; Chou, J.P.; Cornelissen, Th.; Curtin, D.; Dasgupta, M.; Davison, A.; De Almeida Dias, F.; De Cosa, A.; De Roeck, A.; Debenedetti, C.; Doglioni, C.; Ellis, S.D.; Fassi, F.; Ferrando, J.; Fleischmann, S.; Freytsis, M.; Gonzalez Silva, M.L.; Gonzalez de la Hoz, S.; Guescini, F.; Han, Z.; Hook, A.; Hornig, A.; Izaguirre, E.; Jankowiak, M.; Juknevich, J.; Kaci, M.; Kar, D.; Kasieczka, G.; Kogler, R.; Larkoski, A.; Loch, P.; Lopez Mateos, D.; Marzani, S.; Masetti, L.; Mateu, V.; Miller, D.W.; Mishra, K.; Nef, P.; Nordstrom, K.; Oliver Garcia, E.; Penwell, J.; Pilot, J.; Plehn, T.; Rappoccio, S.; Rizzi, A.; Rodrigo, G.; Safonov, A.; Salam, G.P.; Salt, J.; Schaetzel, S.; Schioppa, M.; Schmidt, A.; Scholtz, J.; Schwartzman, A.; Schwartz, M.; Segala, M.; Son, M.; Soyez, G.; Spannowsky, M.; Stewart, I.; Strom, D.; Swiatlowski, M.; Sanchez Martinez, V.; Takeuchi, M.; Thaler, J.; Thompson, E.; Tran, N.V.; Vermilion, C.; Villaplana, M.; Vos, M.; Wacker, J.; Walsh, J.

    2014-01-01

    This report of the BOOST2012 workshop presents the results of four working groups that studied key aspects of jet substructure. We discuss the potential of the description of jet substructure in first-principle QCD calculations and study the accuracy of state-of-the-art Monte Carlo tools. Experimental limitations of the ability to resolve substructure are evaluated, with a focus on the impact of additional proton proton collisions on jet substructure performance in future LHC operating scenarios. A final section summarizes the lessons learnt during the deployment of substructure analyses in searches for new physics in the production of boosted top quarks.

  14. THE ORIGIN OF THE VIRGO STELLAR SUBSTRUCTURE

    Energy Technology Data Exchange (ETDEWEB)

    Carlin, Jeffrey L.; Yam, William; Willett, Benjamin A.; Newberg, Heidi J. [Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180 (United States); Casetti-Dinescu, Dana I.; Girard, Terrence M. [Astronomy Department, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Majewski, Steven R., E-mail: carlij@rpi.edu [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States)

    2012-07-10

    We present three-dimensional space velocities of stars selected to be consistent with membership in the Virgo stellar substructure. Candidates were selected from SA 103, a single 40' Multiplication-Sign 40' field from our proper-motion (PM) survey in Kapteyn's Selected Areas (SAs), based on the PMs, Sloan Digital Sky Survey (SDSS) photometry, and follow-up spectroscopy of 215 stars. The signature of the Virgo substructure is clear in the SDSS color-magnitude diagram (CMD) centered on SA 103, and 16 stars are identified that have high Galactocentric-frame radial velocities (V{sub GSR} > 50 km s{sup -1}) and lie near the CMD locus of Virgo. The implied distance to the Virgo substructure from the candidates is 14 {+-} 3 kpc. We derive mean kinematics from these 16 stars, finding a radial velocity V{sub GSR} = 153 {+-} 22 km s{sup -1} and proper motions ({mu}{sub {alpha}}cos {delta}, {mu}{sub {delta}}) = (- 5.24, -0.91) {+-} (0.43, 0.46) mas yr{sup -1}. From the mean kinematics of these members, we determine that the Virgo progenitor was on an eccentric (e {approx} 0.8) orbit that recently passed near the Galactic center (pericentric distance R{sub p} {approx} 6 kpc). This destructive orbit is consistent with the idea that the substructure(s) in Virgo originated in the tidal disruption of a Milky Way satellite. N-body simulations suggest that the entire cloud-like Virgo substructure (encompassing the 'Virgo Overdensity' and the 'Virgo Stellar Stream') is likely the tidal debris remnant from a recently disrupted massive ({approx}10{sup 9} M{sub Sun }) dwarf galaxy. The model also suggests that some other known stellar overdensities in the Milky Way halo (e.g., the Pisces Overdensity and debris near NGC 2419 and SEGUE 1) are explained by the disruption of the Virgo progenitor.

  15. An online substructure identification method for local structural health monitoring

    Science.gov (United States)

    Hou, Jilin; Jankowski, Łukasz; Ou, Jinping

    2013-09-01

    This paper proposes a substructure isolation method, which uses time series of measured local response for online monitoring of substructures. The proposed monitoring process consists of two key steps: construction of the isolated substructure, and its identification. The isolated substructure is an independent virtual structure, which is numerically isolated from the global structure by placing virtual supports on the interface. First, the isolated substructure is constructed by a specific linear combination of time series of its measured local responses. Then, the isolated substructure is identified using its local natural frequencies extracted from the combined responses. The substructure is assumed to be linear; the outside part of the global structure can have any characteristics. The method has no requirements on the initial state of the structure, and so the process can be carried out repetitively for online monitoring. Online isolation and monitoring is illustrated in a numerical example with a frame model, and then verified in a cantilever beam experiment.

  16. Shaken and stirred: the Milky Way's dark substructures

    Science.gov (United States)

    Sawala, Till; Pihajoki, Pauli; Johansson, Peter H.; Frenk, Carlos S.; Navarro, Julio F.; Oman, Kyle A.; White, Simon D. M.

    2017-06-01

    The predicted abundance and properties of the low-mass substructures embedded inside larger dark matter haloes differ sharply among alternative dark matter models. Too small to host galaxies themselves, these subhaloes may still be detected via gravitational lensing or via perturbations of the Milky Way's globular cluster streams and its stellar disc. Here, we use the Apostle cosmological simulations to predict the abundance and the spatial and velocity distributions of subhaloes in the range 106.5-108.5 M⊙ inside haloes of mass ˜1012 M⊙ in Λ cold dark matter. Although these subhaloes are themselves devoid of baryons, we find that baryonic effects are important. Compared to corresponding dark matter only simulations, the loss of baryons from subhaloes and stronger tidal disruption due to the presence of baryons near the centre of the main halo reduce the number of subhaloes by ˜1/4 to 1/2, independently of subhalo mass, but increasingly towards the host halo centre. We also find that subhaloes have non-Maxwellian orbital velocity distributions, with centrally rising velocity anisotropy and positive velocity bias that reduces the number of low-velocity subhaloes, particularly near the halo centre. We parametrize the predicted population of subhaloes in terms of mass, galactocentric distance and velocities. We discuss implications of our results for the prospects of detecting dark matter substructures and for possible inferences about the nature of dark matter.

  17. Preservation under Substructures modulo Bounded Cores

    CERN Document Server

    Sankaran, Abhisekh; Madan, Vivek; Kamath, Pritish; Chakraborty, Supratik

    2012-01-01

    We investigate a model-theoretic property that generalizes the classical notion of "preservation under substructures". We call this property \\emph{preservation under substructures modulo bounded cores}, and present a syntactic characterization via $\\Sigma_2^0$ sentences for properties of arbitrary structures definable by FO sentences. Towards a sharper characterization, we conjecture that the count of existential quantifiers in the $\\Sigma_2^0$ sentence equals the size of the smallest bounded core. While we do not have a proof of the conjecture yet, we show that it holds for special fragments of FO and also over special classes of structures. We present a (not FO-definable) class of finite structures for which the conjecture fails, but for which the classical {\\L}o\\'s-Tarski preservation theorem holds. As a fallout of our studies, we have obtained combinatorial proofs of the {\\L}o\\'s-Tarski theorem for some of the aforementioned cases.

  18. Towards an understanding of jet substructure

    CERN Document Server

    Dasgupta, Mrinal; Marzani, Simone; Salam, Gavin P

    2013-01-01

    We present first analytic, resummed calculations of the rates at which widespread jet substructure tools tag QCD jets. As well as considering trimming, pruning and the mass-drop tagger, we introduce modified tools with improved analytical and phenomenological behaviours. Most taggers have double logarithmic resummed structures. The modified mass-drop tagger is special in that it involves only single logarithms, and is free from a complex class of terms known as non-global logarithms. The modification of pruning brings an improved ability to discriminate between the different colour structures that characterise signal and background. As we outline in an extensive phenomenological discussion, these results provide valuable insight into the performance of existing tools and help lay robust foundations for future substructure studies.

  19. Jacket Substructure Fatigue Mitigation through Active Control

    DEFF Research Database (Denmark)

    Hanis, Tomas; Natarajan, Anand

    2014-01-01

    As offshore wind farms are being installed farther and in deeper waters offshore, new, and more sophisticated marine substructures such as jackets need to be used. Herein, a 10MW wind turbine mounted on a jacket sub structure at a mean water depth of 50 meters is investigated with regards...... to the fatigue design loads on the braces of the jacket. Since large wind turbines of 10MW rating have low rotor speeds (p), the modal frequencies of the sub structures approach 3p at low wind speeds, which leads to a modal coupling and resonance. Therefore an active control system is developed which provides...... sufficient structural damping and consequently a fatigue reduction at the substructure. The resulting reduction in fatigue design loads on the jacket structure based on the active control system is presented....

  20. Smart variations: Functional substructures for part compatibility

    KAUST Repository

    Zheng, Youyi

    2013-05-01

    As collections of 3D models continue to grow, reusing model parts allows generation of novel model variations. Naïvely swapping parts across models, however, leads to implausible results, especially when mixing parts across different model families. Hence, the user has to manually ensure that the final model remains functionally valid. We claim that certain symmetric functional arrangements (sFarr-s), which are special arrangements among symmetrically related substructures, bear close relation to object functions. Hence, we propose a purely geometric approach based on such substructures to match, replace, and position triplets of parts to create non-trivial, yet functionally plausible, model variations. We demonstrate that starting even from a small set of models such a simple geometric approach can produce a diverse set of non-trivial and plausible model variations. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and Blackwell Publishing Ltd.

  1. Identifying a new particle with jet substructures

    CERN Document Server

    Lim, Sung Hak; Kim, Doojin; Kim, Minho; Kong, Kyoungchul; Park, Myeonghun

    2016-01-01

    We investigate a potential of measuring properties of a heavy resonance X, exploiting jet substructure techniques. Motivated by heavy higgs boson searches, we focus on the decays of X into a pair of (massive) electroweak gauge bosons. More specifically, we consider a hadronic Z boson, which makes it possible to determine properties of X at an earlier stage. For $m_X$ of O(1) TeV, two quarks from a Z boson would be captured as a "merged jet" in a significant fraction of events. The use of the merged jet enables us to consider a Z-induced jet as a reconstructed object without any combinatorial ambiguity. We apply a conventional jet substructure method to extract four-momenta of subjets from a merged jet. We find that jet substructure procedures may enhance features in some kinematic observables formed with subjets. Subjet momenta are fed into the matrix element associated with a given hypothesis on the nature of X, which is further processed to construct a matrix element method (MEM)-based observable. For both ...

  2. Identifying a new particle with jet substructures

    CERN Document Server

    Lim, Sung Hak; Kim, Doojin; Kim, Minho; Kong, Kyoungchul; Park, Myeonghun

    2017-01-01

    We investigate a potential of measuring properties of a heavy resonance X, exploiting jet substructure techniques. Motivated by heavy higgs boson searches, we focus on the decays of X into a pair of (massive) electroweak gauge bosons. More specifically, we consider a hadronic Z boson, which makes it possible to determine properties of X at an earlier stage. For $m_X$ of O(1) TeV, two quarks from a Z boson would be captured as a "merged jet" in a significant fraction of events. The use of the merged jet enables us to consider a Z-induced jet as a reconstructed object without any combinatorial ambiguity. We apply a conventional jet substructure method to extract four-momenta of subjets from a merged jet. We find that jet substructure procedures may enhance features in some kinematic observables formed with subjets. Subjet momenta are fed into the matrix element associated with a given hypothesis on the nature of X, which is further processed to construct a matrix element method (MEM)-based observable. For both ...

  3. Identifying a new particle with jet substructures

    CERN Document Server

    Lim, Sung Hak; Kim, Doojin; Kim, Minho; Kong, Kyoungchul; Park, Myeonghun

    2017-01-01

    We investigate a potential of measuring properties of a heavy resonance X, exploiting jet substructure techniques. Motivated by heavy higgs boson searches, we focus on the decays of X into a pair of (massive) electroweak gauge bosons. More specifically, we consider a hadronic Z boson, which makes it possible to determine properties of X at an earlier stage. For $m_X$ of O(1) TeV, two quarks from a Z boson would be captured as a "merged jet" in a significant fraction of events. The use of the merged jet enables us to consider a Z-induced jet as a reconstructed object without any combinatorial ambiguity. We apply a conventional jet substructure method to extract four-momenta of subjets from a merged jet. We find that jet substructure procedures may enhance features in some kinematic observables formed with subjets. Subjet momenta are fed into the matrix element associated with a given hypothesis on the nature of X, which is further processed to construct a matrix element method (MEM)-based observable. For both ...

  4. Simulations of Strong Gravitational Lensing with Substructure

    CERN Document Server

    Amara, A; Cox, T J; Ostriker, J P; Amara, Adam; Cox, Thomas J.; Ostriker, Jeremiah P.

    2004-01-01

    Galactic sized gravitational lenses are simulated by combining a cosmological N-body simulation and models for the baryonic component of the galaxy. The lens caustics, critical curves, image locations and magnification ratios are calculated by ray-shooting on an adaptive grid. It is found that the simulations do not cause the observed number of violations of the cusp caustic magnification relation. A part of this may be due to an insufficient amount of substructure but even for unsmoothed simulations (with maximal substructure) the factor of three increase in the number of violations still did not match the data. This suggests that other factors play an important role. These may include lensing by structure outside the halo, selection bias and the possibility that a randomly selected galaxy halo may be more irregular, for example due to recent mergers, than the isolated halo used in this study. It is also shown that, with the computed level of substructure, the image magnifications of the Einstein cross type ...

  5. The Origin of the Virgo Stellar Substructure

    CERN Document Server

    Carlin, Jeffrey L; Casetti-Dinescu, Dana I; Willett, Benjamin A; Newberg, Heidi J; Majewski, Steven R; Girard, Terrence M

    2012-01-01

    We present three-dimensional space velocities of stars selected to be consistent with membership in the Virgo stellar substructure. Candidates were selected from SA 103, a single 40x40 arcmin field from our proper motion (PM) survey in Kapteyn's Selected Areas (SAs), based on the PMs, SDSS photometry, and follow-up spectroscopy of 215 stars. The signature of the Virgo substructure is clear in the SDSS color-magnitude diagram (CMD) centered on SA 103, and 16 stars are identified that have high Galactocentric-frame radial velocities (V_GSR > 50 km/s) and lie near the CMD locus of Virgo. The implied distance to the Virgo substructure from the candidates is 14+/-3 kpc. We derive mean kinematics from these 16 stars, finding a radial velocity V_GSR = 153+/-22 km/s and proper motions (mu_alpha*cos(delta), mu_delta) = (-5.24, -0.91)+/-(0.43, 0.46) mas/yr. From the mean kinematics of these members, we determine that the Virgo progenitor was on an eccentric (e ~ 0.8) orbit that recently passed near the Galactic center ...

  6. Composite Octet Searches with Jet Substructure

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Yang; /SLAC; Shelton, Jessie; /Yale U.

    2012-02-14

    Many new physics models with strongly interacting sectors predict a mass hierarchy between the lightest vector meson and the lightest pseudoscalar mesons. We examine the power of jet substructure tools to extend the 7 TeV LHC sensitivity to these new states for the case of QCD octet mesons, considering both two gluon and two b-jet decay modes for the pseudoscalar mesons. We develop both a simple dijet search using only the jet mass and a more sophisticated jet substructure analysis, both of which can discover the composite octets in a dijet-like signature. The reach depends on the mass hierarchy between the vector and pseudoscalar mesons. We find that for the pseudoscalar-to-vector meson mass ratio below approximately 0.2 the simple jet mass analysis provides the best discovery limit; for a ratio between 0.2 and the QCD-like value of 0.3, the sophisticated jet substructure analysis has the best discovery potential; for a ratio above approximately 0.3, the standard four-jet analysis is more suitable.

  7. 随机漂移亚群体等位基因频率分布的假定及在DNA指纹数据中的应用%A Supposed Distribution for Random Drift Substructure of Population and Its Application in DNA Fingerprinting Date

    Institute of Scientific and Technical Information of China (English)

    秦学军; 方积乾; 黎黎

    2000-01-01

    The substructure of population that effects the calculation for matching probability by chance is discussed in this paper. A supposition, that allelic frequency of random drift sub-population conforms with Dirichlet distribution of parameters (where p1,p2,…,pm is the beginning frequency for random drift process, theta is the inbreeding coefficient.), is proved to be consistent with the theory of population genetics and the sampling theory as well.%研究影响计算两DNA指纹偶然匹配率的亚群体结构,首次提出随机漂移各亚群体单个位点等位基因频率服从参数为的Dirichlet分布的假定(p1,p2,…,pm为随机漂移初始频率,θ为近交系数),证明依该分布产生亚群体,其结构、性质与群体遗传理论、样本理论一致;将该分布应用于DNA指纹数据,得到了其它方法的类似结论.

  8. Analysis of East Asia genetic substructure using genome-wide SNP arrays.

    Directory of Open Access Journals (Sweden)

    Chao Tian

    Full Text Available Accounting for population genetic substructure is important in reducing type 1 errors in genetic studies of complex disease. As efforts to understand complex genetic disease are expanded to different continental populations the understanding of genetic substructure within these continents will be useful in design and execution of association tests. In this study, population differentiation (Fst and Principal Components Analyses (PCA are examined using >200 K genotypes from multiple populations of East Asian ancestry. The population groups included those from the Human Genome Diversity Panel [Cambodian, Yi, Daur, Mongolian, Lahu, Dai, Hezhen, Miaozu, Naxi, Oroqen, She, Tu, Tujia, Naxi, Xibo, and Yakut], HapMap [ Han Chinese (CHB and Japanese (JPT], and East Asian or East Asian American subjects of Vietnamese, Korean, Filipino and Chinese ancestry. Paired Fst (Wei and Cockerham showed close relationships between CHB and several large East Asian population groups (CHB/Korean, 0.0019; CHB/JPT, 00651; CHB/Vietnamese, 0.0065 with larger separation with Filipino (CHB/Filipino, 0.014. Low levels of differentiation were also observed between Dai and Vietnamese (0.0045 and between Vietnamese and Cambodian (0.0062. Similarly, small Fst's were observed among different presumed Han Chinese populations originating in different regions of mainland of China and Taiwan (Fst's <0.0025 with CHB. For PCA, the first two PC's showed a pattern of relationships that closely followed the geographic distribution of the different East Asian populations. PCA showed substructure both between different East Asian groups and within the Han Chinese population. These studies have also identified a subset of East Asian substructure ancestry informative markers (EASTASAIMS that may be useful for future complex genetic disease association studies in reducing type 1 errors and in identifying homogeneous groups that may increase the power of such studies.

  9. Partially Hidden Markov Models

    DEFF Research Database (Denmark)

    Forchhammer, Søren Otto; Rissanen, Jorma

    1996-01-01

    Partially Hidden Markov Models (PHMM) are introduced. They differ from the ordinary HMM's in that both the transition probabilities of the hidden states and the output probabilities are conditioned on past observations. As an illustration they are applied to black and white image compression wher...

  10. Free-Interface Modal Synthesis Based Substructural Damage Detection Method

    Directory of Open Access Journals (Sweden)

    Shanghong Chen

    2014-01-01

    Full Text Available Free-interface modal synthesis method is applied to civil structure, and a substructure method is proposed by introducing the method into global sensitivity method. The substructure expression of the derivatives of eigenvalues and eigenvectors with respect to elemental parameters is obtained. The accuracy of the application of free-interface modal synthesis method is evaluated with different retained modes in substructure, and then the effectiveness of the proposed substructure sensitivity method is illustrated through an 11-storey building under both single- and multidamage cases. Both the damage locations and the extent can be effectively identified. By comparing it with the identical results of global sensitivity method, the proposed method can be faster in detecting the damage location and more stable under multidamage cases. Since this substructure sensitivity method only needs to update sensitivity matrix in the substructure with relative small number of DOFs, it may save much computation effort and become more efficient.

  11. Structural integrity of Offshore Wind Power Substructures

    OpenAIRE

    Imafidon, Oliver Osazee

    2010-01-01

    Offshore wind turbine structures are now being developed in relatively deep waters with the purpose of capturing and utilizing the strong winds at sea. The structures must be robust in order to resist extreme loads. To be competitive, a cost reduction in fabrication and installation of wind substructures is necessary and the use of high strength steel has been suggested as one way of achieving this through the design of light-weight structures.The thesis gives an overview of offshore wind tur...

  12. Substructurability: the effect of interface location on a real-time dynamic substructuring test

    Science.gov (United States)

    Terkovics, N.; Neild, S. A.; Lowenberg, M.; Szalai, R.; Krauskopf, B.

    2016-08-01

    A full-scale experimental test for large and complex structures is not always achievable. This can be due to many reasons, the most prominent one being the size limitations of the test. Real-time dynamic substructuring is a hybrid testing method where part of the system is modelled numerically and the rest of the system is kept as the physical test specimen. The numerical-physical parts are connected via actuators and sensors and the interface is controlled by advanced algorithms to ensure that the tested structure replicates the emulated system with sufficient accuracy. The main challenge in such a test is to overcome the dynamic effects of the actuator and associated controller, that inevitably introduce delay into the substructured system which, in turn, can destabilize the experiment. To date, most research concentrates on developing control strategies for stable recreation of the full system when the interface location is given a priori. Therefore, substructurability is mostly studied in terms of control. Here, we consider the interface location as a parameter and study its effect on the stability of the system in the presence of delay due to actuator dynamics and define substructurability as the system's tolerance to delay in terms of the different interface locations. It is shown that the interface location has a major effect on the tolerable delays in an experiment and, therefore, careful selection of it is necessary.

  13. Substructure of fuzzy dark matter halos

    CERN Document Server

    Du, Xiaolong; Niemeyer, Jens C

    2016-01-01

    We derive the halo mass function (HMF) for fuzzy dark matter (FDM) by solving the excursion set problem explicitly with a mass-dependent barrier function, which has not been done before. We find that compared to the naive approach of the Sheth-Tormen HMF for FDM the one we obtain has a higher cut off mass and the cut off mass change less strongly with redshifts. Using merger trees constructed with a modified version of the Lacey & Cole formalism that accounts for suppressed small scale power and the scale-dependent growth of FDM halos and the semi-analytic Galacticus code, we study the statistics of halo substructure including the effects from dynamical friction and tidal stripping. We find that if the dark matter is a mixture of cold dark matter (CDM) and FDM, there will be a suppression on the halo substructure on small scales which may be able to solve the Missing Satellites Problem faced by the pure CDM model. The suppression becomes stronger with increasing FDM fraction or decreasing FDM mass. Thus i...

  14. Identifying a New Particle with Jet Substructures

    CERN Document Server

    Han, Chengcheng; Kim, Minho; Kong, Kyoungchul; Lim, Sung Hak; Park, Myeonghun

    2016-01-01

    We investigate a potential of determining properties of a new heavy resonance of mass $\\mathcal{O}(1)$ TeV which decays to collimated jets via heavy Standard Model intermediary states, exploiting jet substructure techniques. Employing the $Z$ gauge boson as a concrete example for the intermediary state, we utilize a ``merged jet'' defined by a large jet size to capture the two quarks from its decay. The use of the merged jet benefits the identification of a $Z$-induced jet as a single, reconstructed object without any combinatorial ambiguity. We find that jet substructure procedures may enhance features in some kinematic observables formed with subjet four-momenta extracted from a merged jet. This observation motivates us to feed subjet momenta into the matrix elements associated with plausible hypotheses on the nature of the heavy resonance, which are further processed to construct a matrix element method (MEM)-based observable. For both moderately and highly boosted $Z$ bosons, we demonstrate that the ME...

  15. Substructure of fuzzy dark matter haloes

    Science.gov (United States)

    Du, Xiaolong; Behrens, Christoph; Niemeyer, Jens C.

    2017-02-01

    We derive the halo mass function (HMF) for fuzzy dark matter (FDM) by solving the excursion set problem explicitly with a mass-dependent barrier function, which has not been done before. We find that compared to the naive approach of the Sheth-Tormen HMF for FDM, our approach has a higher cutoff mass and the cutoff mass changes less strongly with redshifts. Using merger trees constructed with a modified version of the Lacey & Cole formalism that accounts for suppressed small-scale power and the scale-dependent growth of FDM haloes and the semi-analytic GALACTICUS code, we study the statistics of halo substructure including the effects from dynamical friction and tidal stripping. We find that if the dark matter is a mixture of cold dark matter (CDM) and FDM, there will be a suppression on the halo substructure on small scales which may be able to solve the missing satellites problem faced by the pure CDM model. The suppression becomes stronger with increasing FDM fraction or decreasing FDM mass. Thus, it may be used to constrain the FDM model.

  16. Entanglement without hidden nonlocality

    Science.gov (United States)

    Hirsch, Flavien; Túlio Quintino, Marco; Bowles, Joseph; Vértesi, Tamás; Brunner, Nicolas

    2016-11-01

    We consider Bell tests in which the distant observers can perform local filtering before testing a Bell inequality. Notably, in this setup, certain entangled states admitting a local hidden variable model in the standard Bell scenario can nevertheless violate a Bell inequality after filtering, displaying so-called hidden nonlocality. Here we ask whether all entangled states can violate a Bell inequality after well-chosen local filtering. We answer this question in the negative by showing that there exist entangled states without hidden nonlocality. Specifically, we prove that some two-qubit Werner states still admit a local hidden variable model after any possible local filtering on a single copy of the state.

  17. Safety Evaluation of a Hybrid Substructure for Offshore Wind Turbine

    Directory of Open Access Journals (Sweden)

    Min-Su Park

    2016-01-01

    Full Text Available Towers and rotor-nacelles are being enlarged to respond to the need for higher gross generation of the wind turbines. However, the accompanying enlargement of the substructure supporting these larger offshore wind turbines makes it strongly influenced by the effect of wave forces. In the present study, the hybrid substructure is suggested to reduce the wave forces by composing a multicylinder having different radii near free surface and a gravity substructure at the bottom of the multicylinder. In addition, the reaction forces acting on the substructure due to the very large dead load of the offshore wind turbine require very firm foundations. This implies that the dynamic pile-soil interaction has to be fully considered. Therefore, ENSOFT Group V7.0 is used to calculate the stiffness matrices on the pile-soil interaction conditions. These matrices are then used together with the loads at TP (Transition Piece obtained from GH-Bladed for the structural analysis of the hybrid substructure by ANSYS ASAS. The structural strength and deformation are evaluated to derive an ultimate structural safety of the hybrid substructure for various soil conditions and show that the first few natural frequencies of the substructure are heavily influenced by the wind turbine. Therefore, modal analysis is carried out through GH-Bladed to examine the resonance between the wind turbine and the hybrid substructure.

  18. Lens Mapping of Dark Matter Substructure with VSOP-2

    Science.gov (United States)

    Ohashi, S.; Chiba, M.; Inoue, K. T.

    2009-08-01

    Hierarchical clustering models of cold dark matter (CDM) predict that about 5% - 10% of a galaxy-sized halo with mass ˜ 1012 solar masses (M⊙ ) resides in substructures (CDM subhalos) with masses ⪉ 108 M⊙. To directly identify such substructures, we propose to observe radio continuum emission from multiply imaged QSOs using VSOP-2 with a high angular resolution.

  19. Factorization for substructures of boosted Higgs jets

    Science.gov (United States)

    Isaacson, Joshua; Li, Hsiang-nan; Li, Zhao; Yuan, C.-P.

    2017-08-01

    We present a perturbative QCD factorization formula for substructures of an energetic Higgs jet, taking the energy profile resulting from the H → b b bar decay as an example. The formula is written as a convolution of a hard Higgs decay kernel with two b-quark jet functions and a soft function that links the colors of the two b quarks. We derive an analytical expression to approximate the energy profile within a boosted Higgs jet, which significantly differs from those of ordinary QCD jets. This formalism also extends to boosted W and Z bosons in their hadronic decay modes, allowing an easy and efficient discrimination of fat jets produced from different processes.

  20. Substructure of Highly Boosted Massive Jets

    Energy Technology Data Exchange (ETDEWEB)

    Alon, Raz [Weizmann Inst. of Science, Rehovot (Israel)

    2012-10-01

    Modern particle accelerators enable researchers to study new high energy frontiers which have never been explored before. This realm opens possibilities to further examine known fields such as Quantum Chromodynamics. In addition, it allows searching for new physics and setting new limits on the existence of such. This study examined the substructure of highly boosted massive jets measured by the CDF II detector. Events from 1.96 TeV proton-antiproton collisions at the Fermilab Tevatron Collider were collected out of a total integrated luminosity of 5.95 fb$^{-1}$. They were selected to have at least one jet with transverse momentum above 400 GeV/c. The jet mass, angularity, and planar flow were measured and compared with predictions of perturbative Quantum Chromodynamics, and were found to be consistent with the theory. A search for boosted top quarks was conducted and resulted in an upper limit on the production cross section of such top quarks.

  1. Factorization for substructures of boosted Higgs jets

    CERN Document Server

    Isaacson, Joshua; Li, Zhao; Yuan, C -P

    2015-01-01

    We present a perturbative QCD factorization formula for substructures of an energetic Higgs jet, taking the energy profile resulting from the $H\\to b\\bar b$ decay as an example. The formula is written as a convolution of a hard Higgs decay kernel with two $b$-quark jet functions and a soft function that links the colors of the two $b$ quarks. We derive an analytical expression to approximate the energy profile within a boosted Higgs jet, which significantly differs from those of ordinary QCD jets. This formalism also extends to boosted $W$ and $Z$ bosons in their hadronic decay modes, allowing an easy and efficient discrimination of fat jets produced from different processes.

  2. Hidden circuits and argumentation

    Science.gov (United States)

    Leinonen, Risto; Kesonen, Mikko H. P.; Hirvonen, Pekka E.

    2016-11-01

    Despite the relevance of DC circuits in everyday life and schools, they have been shown to cause numerous learning difficulties at various school levels. In the course of this article, we present a flexible method for teaching DC circuits at lower secondary level. The method is labelled as hidden circuits, and the essential idea underlying hidden circuits is in hiding the actual wiring of DC circuits, but to make their behaviour evident for pupils. Pupils are expected to find out the wiring of the circuit which should enhance their learning of DC circuits. We present two possible ways to utilise hidden circuits in a classroom. First, they can be used to test and enhance pupils’ conceptual understanding when pupils are expected to find out which one of the offered circuit diagram options corresponds to the actual circuit shown. This method aims to get pupils to evaluate the circuits holistically rather than locally, and as a part of that aim this method highlights any learning difficulties of pupils. Second, hidden circuits can be used to enhance pupils’ argumentation skills with the aid of argumentation sheet that illustrates the main elements of an argument. Based on the findings from our co-operating teachers and our own experiences, hidden circuits offer a flexible and motivating way to supplement teaching of DC circuits.

  3. How Hidden Can Be Even More Hidden?

    CERN Document Server

    Fraczek, Wojciech; Szczypiorski, Krzysztof

    2011-01-01

    The paper presents Deep Hiding Techniques (DHTs) that define general techniques that can be applied to every network steganography method to improve its undetectability and make steganogram extraction harder to perform. We define five groups of techniques that can make steganogram less susceptible to detection and extraction. For each of the presented group, examples of the usage are provided based on existing network steganography methods. To authors' best knowledge presented approach is the first attempt in the state of the art to systematically describe general solutions that can make steganographic communication more hidden and steganogram extraction harder to perform.

  4. Search for Hidden Particles

    CERN Multimedia

    The SHiP Experiment is a new general-purpose fixed target facility at the SPS to search for hidden particles as predicted by a very large number of recently elaborated models of Hidden Sectors which are capable of accommodating dark matter, neutrino oscillations, and the origin of the full baryon asymmetry in the Universe. Specifically, the experiment is aimed at searching for very weakly interacting long lived particles including Heavy Neutral Leptons - right-handed partners of the active neutrinos; light supersymmetric particles - sgoldstinos, etc.; scalar, axion and vector portals to the hidden sector. The high intensity of the SPS and in particular the large production of charm mesons with the 400 GeV beam allow accessing a wide variety of light long-lived exotic particles of such models and of SUSY. Moreover, the facility is ideally suited to study the interactions of tau neutrinos.

  5. How well can cold-dark-matter substructures account for the observed radio flux-ratio anomalies?

    CERN Document Server

    Xu, Dandan; Gao, Liang; Wang, Jie; Frenk, Carlos; Mao, Shude; Schneider, Peter; Springel, Volker

    2014-01-01

    Discrepancies between the observed and model-predicted radio flux ratios are seen in a number of quadruply-lensed quasars. The most favored interpretation of these anomalies is that CDM substructures present in lensing galaxies perturb the lens potentials and alter image magnifications and thus flux ratios. So far no consensus has emerged regarding whether or not the predicted CDM substructure abundance fully accounts for the lensing flux anomaly observations. Accurate modeling relies on a realistic lens sample in terms of both the lens environment and internal structures and substructures. In this paper we construct samples of generalised and specific lens potentials, to which we add (rescaled) subhalo populations from the galaxy-scale Aquarius and the cluster-scale Phoenix simulation suites. We further investigate the lensing effects from subhalos of masses several orders of magnitude below the simulation resolution limit. The resulting flux ratio distributions are compared to the currently best available s...

  6. Cluster X-Ray Substructure and Radio Galaxy Correlations

    Science.gov (United States)

    Ledlow, M. J.; Burns, J. O.

    1994-12-01

    Current wisdom suggests that X-ray substructure in the intracluster medium (ICM) is fairly common in galaxy clusters. This substructure takes the form of elongations, isophotal twisting, asymmetries, and sub-clumping. Substructure is also frequently present in kinematical analysis of the galaxy velocity and spatial distributions. These features include bimodality, kurtosis or skewness, and non-Gaussian velocity distributions. Consistent with the observations, Hydro/N-Body simulations suggest that cluster-subcluster mergers may be the culprit to explain these features in the ICM gas distribution, and would indicate that many clusters, even at the present epoch, are still undergoing significant dynamical evolution. From a sample of X-ray images from the Einstein satellite and, more recently, the ROSAT mission, Burns et al. (1994) found a significant correlation between the positions of radio galaxies and subclumps within the cluster-scale X-ray emission. Burns et al. have suggested that radio galaxies reside in the residue of cluster/sub-cluster merging sites, and may therefore act as pointers to clusters with ongoing and intersting dynamical activity. We are following up these ideas with a detailed substructure analysis, and a comparison to a sample of clusters without radio galaxies. In order to determine the signficance of substructure, we have reanalyzed the X-ray images using a Bootstrap-Resampling Monte-Carlo technique. In this method, asymmetries, elongations, and other forms of substructure are evaluated using a moment-analysis similar to M{o}hr et al. (1994), with the advantage that we need not assume apriori any specific substructure-free model for the source (\\ie\\ a Beta-model). The significance of individual features is determined solely from a comparison to statistical fluctuations (including noise) of the actual data. Using this technique, we place limits on the fraction of clusters with significant substructure and test the radio galaxy/substructure

  7. Solar Hidden Photon Search

    CERN Document Server

    Schwarz, Matthias; Redondo, Javier; Ringwald, Andreas; Wiedemann, Guenter

    2011-01-01

    The Solar Hidden Photon Search (SHIPS) is a joint astroparticle project of the Hamburger Sternwarte and DESY. The main target is to detect the solar emission of a new species of particles, so called Hidden Photons (HPs). Due to kinetic mixing, photons and HPs can convert into each other as they propagate. A small number of solar HPs - originating from photon to HP oscillations in the interior of the Sun - can be converted into photons in a long vacuum pipe pointing to the Sun - the SHIPS helioscope.

  8. Solar Hidden Photon Search

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, Matthias; Wiedemann, Guenter [Hamburg Univ. (Germany). Sternwarte; Lindner, Axel; Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Redondo, Javier [Max-Planck-Institut fuer Physik und Astrophysik, Muenchen (Germany)

    2011-11-15

    The Solar Hidden Photon Search (SHIPS) is a joint astroparticle project of the Hamburger Sternwarte and DESY. The main target is to detect the solar emission of a new species of particles, so called Hidden Photons (HPs). Due to kinetic mixing, photons and HPs can convert into each other as they propagate. A small number of solar HPs - originating from photon to HP oscillations in the interior of the Sun - can be converted into photons in a long vacuum pipe pointing to the Sun - the SHIPS helioscope. (orig.)

  9. Substructure System Identification for Finite Element Model Updating

    Science.gov (United States)

    Craig, Roy R., Jr.; Blades, Eric L.

    1997-01-01

    This report summarizes research conducted under a NASA grant on the topic 'Substructure System Identification for Finite Element Model Updating.' The research concerns ongoing development of the Substructure System Identification Algorithm (SSID Algorithm), a system identification algorithm that can be used to obtain mathematical models of substructures, like Space Shuttle payloads. In the present study, particular attention was given to the following topics: making the algorithm robust to noisy test data, extending the algorithm to accept experimental FRF data that covers a broad frequency bandwidth, and developing a test analytical model (TAM) for use in relating test data to reduced-order finite element models.

  10. Substructuring by Lagrange multipliers for solids and plates

    Energy Technology Data Exchange (ETDEWEB)

    Mandel, J.; Tezaur, R. [Univ. of Colorado, Denver, CO (United States); Farhat, C. [Univ. of Colorado, Boulder, CO (United States)

    1996-12-31

    We present principles and theoreretical foundation of a substructuring method for large structural problems. The algorithm is preconditioned conjugate gradients on a subspace for the dual problem. The preconditioning is proved asymptotically optimal and the method is shown to be parallel scalable, i.e., the condition number is bounded independently of the number of substructures. For plate problems, a special modification is needed that retains continuity of the displacement solution at substructure crosspoints, resulting in an asymptically optimal method. The results are confirmed by numerical experiments.

  11. The Aspen Framework for Dark Matter Substructure Inference from Strong Gravitational Lensing Observations

    Science.gov (United States)

    Moustakas, Leonidas A.; Cyr-Racine, Francis-Yan; Keeton, Charles R.

    2016-01-01

    The properties of the dark matter particle or particles lead to different small scale halo populations, distributions, and evolution over cosmic time. We introduce a new method for characterizing the properties of substructure within galaxies through the power spectrum of potential fluctuations, and demonstrate how complete sets of multiwavelength imaging and time domain observations can be processed directly to infer all facets of the strong gravitational lensing components and source properties, including the dark matter substructure power spectrum constraints. We are able to take advantage of analysis parallels with cosmic background radiation techniques, and furthermore demonstrate how this technique, dubbed The Aspen Framework, reduces to the long-standing approach of working with reduced or derived observable quantities in lensing.

  12. Measuring the resistance of different substructure materials by ...

    African Journals Online (AJOL)

    Measuring the resistance of different substructure materials by sticking them to dentine with ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search ... Materials and Methods: In an in vitro study, 72 central upper front teeth were ...

  13. Measuring the resistance of different substructure materials by ...

    African Journals Online (AJOL)

    2015-05-26

    May 26, 2015 ... cement (Panavia F 2.0 Light) and a self‑adhesive resin cement ... Resistance of substructure materials with two cements. 731 ..... is known to have several disadvantages like the increase .... There are no conflicts of interest.

  14. Substructures formation induced by gravitational tides?

    CERN Document Server

    Renaud, F; Naab, T; Boily, C M

    2009-01-01

    Physics lectures always refer to the tides as a disruptive effect. However, tides can also be compressive. When the potential of two galaxies overlap, as happens during a merger, fully compressive tides can develop and have a strong impact on the dynamics of substructures such as star clusters or tidal dwarf galaxies. Using N-body simulations of a large set of mergers, we noticed the importance of these tidal modes at cluster scale. With a model of the Antennae galaxies, we conclude that the positions and timescales of these tidal modes match the actual distribution of young clusters. A detailed study of the statistics of the compressive tides shows a stunning correlation between this purely gravitational effect and the observed properties of the star clusters. In this contribution, we introduce the concept of compressive tide and show its relevance in the special case of the Antennae galaxies. We extend our conclusions to a broad range of parameters and discuss their implications on several critical points s...

  15. Signatures of LCDM substructure in tidal debris

    CERN Document Server

    Siegal-Gaskins, Jennifer M

    2007-01-01

    In the past decade, surveys of the stellar component of the Galaxy such as SDSS and 2MASS have revealed a number of stellar streams. Current and future observations are rapidly increasing the precision and quantity of data available, raising the possibility of using tidal streams to constrain the distribution of dark matter in the halo. Simulations of hierarchical structure formation in LCDM cosmologies predict that the dark matter halo of a galaxy like the Milky Way contains a smooth component as well as hundreds of subhalos with masses of ~10^8 solar masses and greater, and it has been suggested that the existence of coherent tidal streams is incompatible with the expected abundance of substructure. We investigate the properties of tidal streams arising from the disruption of satellites in a variety of dark matter halo models. In general, we find that the halo shape and the specific orbital path more strongly determine the degree of disruption of the satellite than does the presence or absence of substructu...

  16. THE SEGUE K GIANT SURVEY. III. QUANTIFYING GALACTIC HALO SUBSTRUCTURE

    Energy Technology Data Exchange (ETDEWEB)

    Janesh, William; Morrison, Heather L.; Ma, Zhibo; Harding, Paul [Department of Astronomy, Case Western Reserve University, Cleveland, OH 44106 (United States); Rockosi, Constance [UCO/Lick Observatory, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Starkenburg, Else [Department of Physics and Astronomy, University of Victoria, P.O. Box 1700, STN CSC, Victoria BC V8W 3P6 (Canada); Xue, Xiang Xiang; Rix, Hans-Walter [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Beers, Timothy C. [Department of Physics and JINA Center for the Evolution of the Elements, University of Notre Dame, Notre Dame, IN 46556 (United States); Johnson, Jennifer [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Lee, Young Sun [Department of Astronomy and Space Science, Chungnam National University, Daejeon 34134 (Korea, Republic of); Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)

    2016-01-10

    We statistically quantify the amount of substructure in the Milky Way stellar halo using a sample of 4568 halo K giant stars at Galactocentric distances ranging over 5–125 kpc. These stars have been selected photometrically and confirmed spectroscopically as K giants from the Sloan Digital Sky Survey’s Sloan Extension for Galactic Understanding and Exploration project. Using a position–velocity clustering estimator (the 4distance) and a model of a smooth stellar halo, we quantify the amount of substructure in the halo, divided by distance and metallicity. Overall, we find that the halo as a whole is highly structured. We also confirm earlier work using blue horizontal branch (BHB) stars which showed that there is an increasing amount of substructure with increasing Galactocentric radius, and additionally find that the amount of substructure in the halo increases with increasing metallicity. Comparing to resampled BHB stars, we find that K giants and BHBs have similar amounts of substructure over equivalent ranges of Galactocentric radius. Using a friends-of-friends algorithm to identify members of individual groups, we find that a large fraction (∼33%) of grouped stars are associated with Sgr, and identify stars belonging to other halo star streams: the Orphan Stream, the Cetus Polar Stream, and others, including previously unknown substructures. A large fraction of sample K giants (more than 50%) are not grouped into any substructure. We find also that the Sgr stream strongly dominates groups in the outer halo for all except the most metal-poor stars, and suggest that this is the source of the increase of substructure with Galactocentric radius and metallicity.

  17. A new interface element for connecting independently modeled substructures

    Science.gov (United States)

    Ransom, Jonathan B.; Mccleary, Susan L.; Aminpour, Mohammad A.

    1993-01-01

    A new interface element based on the hybrid variational formulation is presented and demonstrated. The element provides a means of connecting independently modeled substructures whose nodes along the common boundary need not be coincident. The interface element extends previous work to include connecting an arbitrary number of substructures, the use of closed and generally curved interfaces, and the use of multiple, possibly nested, interfaces. Several applications of the element are presented and aspects of the implementation are discussed.

  18. Searches for new physics using jet grooming and substructure

    CERN Document Server

    Burr, Jonathan Thomas Peter; The ATLAS collaboration

    2017-01-01

    Models predicting the production and decay of supersymmetric (SUSY) particles often have promising search channels involving decays through heavy intermediate states such as top quarks and heavy bosons. However, unlike in most exotics scenarios these heavy states are only moderately boosted which can make traditional substructure techniques less useful and motivates the development of alternative techniques. The results of several SUSY analyses using substructure techniques are presented.

  19. Detection of Lensing Substructure Using ALMA Observations of the Dusty Galaxy SDP.81

    Science.gov (United States)

    Hezaveh, Yashar D.; Dalal, Neal; Marrone, Daniel P.; Mao, Yao-Yuan; Morningstar, Warren; Wen, Di; Blandford, Roger D.; Carlstrom, John E.; Fassnacht, Christopher D.; Holder, Gilbert P.; Kemball, Athol; Marshall, Philip J.; Murray, Norman; Perreault Levasseur, Laurence; Vieira, Joaquin D.; Wechsler, Risa H.

    2016-05-01

    We study the abundance of substructure in the matter density near galaxies using ALMA Science Verification observations of the strong lensing system SDP.81. We present a method to measure the abundance of subhalos around galaxies using interferometric observations of gravitational lenses. Using simulated ALMA observations we explore the effects of various systematics, including antenna phase errors and source priors, and show how such errors may be measured or marginalized. We apply our formalism to ALMA observations of SDP.81. We find evidence for the presence of a M = 108.96±0.12 M ⊙ subhalo near one of the images, with a significance of 6.9σ in a joint fit to data from bands 6 and 7; the effect of the subhalo is also detected in both bands individually. We also derive constraints on the abundance of dark matter (DM) subhalos down to M ˜ 2 × 107 M ⊙, pushing down to the mass regime of the smallest detected satellites in the Local Group, where there are significant discrepancies between the observed population of luminous galaxies and predicted DM subhalos. We find hints of additional substructure, warranting further study using the full SDP.81 data set (including, for example, the spectroscopic imaging of the lensed carbon monoxide emission). We compare the results of this search to the predictions of ΛCDM halos, and find that given current uncertainties in the host halo properties of SDP.81, our measurements of substructure are consistent with theoretical expectations. Observations of larger samples of gravitational lenses with ALMA should be able to improve the constraints on the abundance of galactic substructure.

  20. Hidden neural networks

    DEFF Research Database (Denmark)

    Krogh, Anders Stærmose; Riis, Søren Kamaric

    1999-01-01

    A general framework for hybrids of hidden Markov models (HMMs) and neural networks (NNs) called hidden neural networks (HNNs) is described. The article begins by reviewing standard HMMs and estimation by conditional maximum likelihood, which is used by the HNN. In the HNN, the usual HMM probability...... parameters are replaced by the outputs of state-specific neural networks. As opposed to many other hybrids, the HNN is normalized globally and therefore has a valid probabilistic interpretation. All parameters in the HNN are estimated simultaneously according to the discriminative conditional maximum...... likelihood criterion. The HNN can be viewed as an undirected probabilistic independence network (a graphical model), where the neural networks provide a compact representation of the clique functions. An evaluation of the HNN on the task of recognizing broad phoneme classes in the TIMIT database shows clear...

  1. Coupling of Hidden Sector

    CERN Document Server

    Królikowski, Wojciech

    2016-01-01

    A hypothetic Hidden Sector of the Universe, consisting of sterile fermions ("sterinos") and sterile mediating bosons ("sterons") of mass dimension 1 (not 2!) - the last described by an antisymmetric tensor field - requires to exist also a scalar isovector and scalar isoscalar in order to be able to construct electroweak invariant coupling (before spontaneously breaking its symmetry). The introduced scalar isoscalar might be a resonant source for the diphoton excess of 750 GeV, suggested recently by experiment.

  2. Modelling proteins' hidden conformations to predict antibiotic resistance

    Science.gov (United States)

    Hart, Kathryn M.; Ho, Chris M. W.; Dutta, Supratik; Gross, Michael L.; Bowman, Gregory R.

    2016-10-01

    TEM β-lactamase confers bacteria with resistance to many antibiotics and rapidly evolves activity against new drugs. However, functional changes are not easily explained by differences in crystal structures. We employ Markov state models to identify hidden conformations and explore their role in determining TEM's specificity. We integrate these models with existing drug-design tools to create a new technique, called Boltzmann docking, which better predicts TEM specificity by accounting for conformational heterogeneity. Using our MSMs, we identify hidden states whose populations correlate with activity against cefotaxime. To experimentally detect our predicted hidden states, we use rapid mass spectrometric footprinting and confirm our models' prediction that increased cefotaxime activity correlates with reduced Ω-loop flexibility. Finally, we design novel variants to stabilize the hidden cefotaximase states, and find their populations predict activity against cefotaxime in vitro and in vivo. Therefore, we expect this framework to have numerous applications in drug and protein design.

  3. Hidden variables and hidden time in quantum theory

    OpenAIRE

    Kurakin, Pavel V.

    2005-01-01

    Bell's theorem proves only that hidden variables evolving in true physical time can't exist; still the theorem's meaning is usually interpreted intolerably wide. The concept of hidden time (and, in general, hidden space-time) is introduced. Such concept provides a whole new class of physical theories, fully compatible with current knowledge, but giving new tremendous possibilities. Those theories do not violate Bell's theorem.

  4. Caldera rim collapse: A hidden volcanic hazard

    OpenAIRE

    Merle, Olivier; Michon, Laurent; Bachèlery, Patrick

    2008-01-01

    International audience; Following the emblematic flank collapse of Mount St Helens in 1981, numerous models of flank sliding have been proposed. These models have allowed to largely improve the understanding of mechanisms involved in such landslides, which represent a tremendous risk for populations living around volcanoes. In this article, a new mode of landslide formation, related to buried calderas, is described. The model emphasizes the paramount importance of the hidden ring fault that, ...

  5. The SEGUE K Giant Survey. III. Quantifying Galactic Halo Substructure

    CERN Document Server

    Janesh, William; Ma, Zhibo; Harding, Paul; Rockosi, Constance; Starkenburg, Else; Xue, Xiang Xiang; Rix, Hans-Walter; Beers, Timothy C; Johnson, Jennifer; Lee, Young Sun; Schneider, Donald P

    2015-01-01

    We statistically quantify the amount of substructure in the Milky Way stellar halo using a sample of 4568 halo K giant stars at Galactocentric distances ranging over 5-125 kpc. These stars have been selected photometrically and confirmed spectroscopically as K giants from the Sloan Digital Sky Survey's SEGUE project. We use a position-velocity clustering estimator (the 4distance) and a smooth stellar halo model to quantify the amount of substructure in the halo. Overall, we find that the halo as a whole is highly structured, and confirm earlier work using BHB stars which showed that there is an increasing amount of substructure with increasing Galactocentric radius. In addition, we find that the amount of substructure in the halo increases with increasing metallicity, and that the K giant sample shows significantly stronger substructure than the BHB stars, which only sample the most metal poor stars. Using a friends-of-friends algorithm to identify groups, we find that a large fraction ($\\sim 33\\%$) of the st...

  6. Quantifying the Significance of Substructure in Coronal Loops

    Science.gov (United States)

    McKeough, K. B. D.; Kashyap, V.; McKillop, S.

    2014-12-01

    A method to infer the presence of small-scale substructure in SDO/AIA (Atmospheric Imaging Assembly on the Solar Dynamics Observatory) images of coronal loops is developed. We can classify visible loop structure based on this propensity to show substructure which puts constraints on contemporary solutions to the coronal heating problem. The method uses the Bayesian algorithm Low-count Image Reconstruction and Analysis (LIRA) to infer the multi-scale component of the loops which describes deviations from a smooth model. The increase in contrast of features in this multi-scale component is determined using a statistic that estimates the sharpness across the image. Regions with significant substructure are determined using p-value upper bounds. We are able to locate substructure visible in Hi-C (High-Resolution Coronal Imager) data that are not salient features in the corresponding AIA image. Looking at coronal loops at different regions of the Sun (e.g., low-lying structure and loops in the upper corona) we are able to map where detectable substructure exists and thus the influence of the nanoflare heating process. We acknowledge support from AIA under contract SP02H1701R from Lockheed-Martin to SAO.

  7. The Genetics of Mexico Recapitulates Native American Substructure and Affects Biomedical Traits

    Science.gov (United States)

    Moreno-Estrada, Andrés; Gignoux, Christopher R.; Fernández-López, Juan Carlos; Zakharia, Fouad; Sikora, Martin; Contreras, Alejandra V.; Acuña-Alonzo, Victor; Sandoval, Karla; Eng, Celeste; Romero-Hidalgo, Sandra; Ortiz-Tello, Patricia; Robles, Victoria; Kenny, Eimear E.; Nuño-Arana, Ismael; Barquera-Lozano, Rodrigo; Macín-Pérez, Gastón; Granados-Arriola, Julio; Huntsman, Scott; Galanter, Joshua M.; Via, Marc; Ford, Jean G.; Chapela, Rocío; Rodriguez-Cintron, William; Rodríguez-Santana, Jose R.; Romieu, Isabelle; Sienra-Monge, Juan José; Navarro, Blanca del Rio; London, Stephanie J.; Ruiz-Linares, Andrés; Garcia-Herrera, Rodrigo; Estrada, Karol; Hidalgo-Miranda, Alfredo; Jimenez-Sanchez, Gerardo; Carnevale, Alessandra; Soberón, Xavier; Canizales-Quinteros, Samuel; Rangel-Villalobos, Héctor; Silva-Zolezzi, Irma; Burchard, Esteban Gonzalez; Bustamante, Carlos D.

    2014-01-01

    Mexico harbors great cultural and ethnic diversity, yet fine-scale patterns of human genome-wide variation from this region remain largely uncharacterized. We studied genomic variation within Mexico from over 1,000 individuals representing 20 indigenous and 11 mestizo populations. We found striking genetic stratification among indigenous populations within Mexico at varying degrees of geographic isolation. Some groups were as differentiated as Europeans are from East Asians. Pre-Columbian genetic substructure is recapitulated in the indigenous ancestry of admixed mestizo individuals across the country. Furthermore, two independently phenotyped cohorts of Mexicans and Mexican Americans showed a significant association between sub-continental ancestry and lung function. Thus, accounting for fine-scale ancestry patterns is critical for medical and population genetic studies within Mexico, in Mexican-descent populations, and likely in many other populations worldwide. PMID:24926019

  8. Functional group and substructure searching as a tool in metabolomics.

    Directory of Open Access Journals (Sweden)

    Masaaki Kotera

    Full Text Available BACKGROUND: A direct link between the names and structures of compounds and the functional groups contained within them is important, not only because biochemists frequently rely on literature that uses a free-text format to describe functional groups, but also because metabolic models depend upon the connections between enzymes and substrates being known and appropriately stored in databases. METHODOLOGY: We have developed a database named "Biochemical Substructure Search Catalogue" (BiSSCat, which contains 489 functional groups, >200,000 compounds and >1,000,000 different computationally constructed substructures, to allow identification of chemical compounds of biological interest. CONCLUSIONS: This database and its associated web-based search program (http://bisscat.org/ can be used to find compounds containing selected combinations of substructures and functional groups. It can be used to determine possible additional substrates for known enzymes and for putative enzymes found in genome projects. Its applications to enzyme inhibitor design are also discussed.

  9. Ancient Substructure in Early mtDNA Lineages of Southern Africa

    OpenAIRE

    Barbieri, Chiara; Vicente, Mário; Rocha, Jorge; Mpoloka, Sununguko W.; Stoneking, Mark; Pakendorf, Brigitte

    2013-01-01

    Among the deepest-rooting clades in the human mitochondrial DNA (mtDNA) phylogeny are the haplogroups defined as L0d and L0k, which are found primarily in southern Africa. These lineages are typically present at high frequency in the so-called Khoisan populations of hunter-gatherers and herders who speak non-Bantu languages, and the early divergence of these lineages led to the hypothesis of ancient genetic substructure in Africa. Here we update the phylogeny of the basal haplogroups L0d and ...

  10. Burden of asymptomatic malaria among a tribal population in a forested village of central India: a hidden challenge for malaria control in India.

    Science.gov (United States)

    Chourasia, M K; Raghavendra, K; Bhatt, R M; Swain, D K; Valecha, N; Kleinschmidt, I

    2017-06-01

    Chhattisgarh in India is a malaria-endemic state with seven southern districts that contributes approximately 50-60% of the reported malaria cases in the state every year. The problem is further complicated due to asymptomatic malaria cases which are largely responsible for persistent transmission. This study was undertaken in one of the forested villages of the Keshkal subdistrict in Kondagaon district to ascertain the proportion of the population harbouring subclinical malarial infections. Community-based cross-sectional study. Mass blood surveys were undertaken of the entire population of the village in the post-monsoon seasons of 2013 and 2014. Fingerprick blood smears were prepared from individuals of all ages to detect malaria infections in their blood. Individuals with fever at the time of the survey were tested with rapid diagnostic tests, and parasitaemia in thick blood smears was confirmed by microscopy. Malaria-positive cases were treated with anti-malarials in accordance with the national drug policy. Peripheral blood smears of 134 and 159 individuals, including children, were screened for malaria infection in 2013 and 2014, respectively. Overall, the malaria slide positivity rates were 27.6% and 27.7% in 2013 and 2014, respectively, and the prevalence rates of asymptomatic malaria were 20% and 22.8%. This study showed that, for two consecutive years, the prevalence of asymptomatic malaria infection was significantly higher among children aged ≤14 years (34.4% and 34.1% for 2013 and 2014, respectively) compared with adults (15.2% and 18.2% for 2013 and 2014, respectively; P = 0.023 and 0.04, respectively). The number of asymptomatic malaria cases, especially Plasmodium falciparum, is significant, reinforcing the underlying challenge facing the malaria elimination programme in India. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Novel SHM method to locate damages in substructures based on VARX models

    Science.gov (United States)

    Ugalde, U.; Anduaga, J.; Martínez, F.; Iturrospe, A.

    2015-07-01

    A novel damage localization method is proposed, which is based on a substructuring approach and makes use of Vector Auto-Regressive with eXogenous input (VARX) models. The substructuring approach aims to divide the monitored structure into several multi-DOF isolated substructures. Later, each individual substructure is modelled as a VARX model, and the health of each substructure is determined analyzing the variation of the VARX model. The method allows to detect whether the isolated substructure is damaged, and besides allows to locate and quantify the damage within the substructure. It is not necessary to have a theoretical model of the structure and only the measured displacement data is required to estimate the isolated substructure's VARX model. The proposed method is validated by simulations of a two-dimensional lattice structure.

  12. Constraining the Milky Way potential using the dynamical kinematic substructures

    NARCIS (Netherlands)

    Monari, G.; Antoja Castelltort, Teresa; Helmi, A.; Reyle, C; Robin, A; Schultheis, M

    2012-01-01

    We present a method to constrain the potential of the non-axisymmetric components of the Galaxy using the kinematics of stars in the solar neighborhood. The basic premise is that dynamical substructures in phase-space (i.e. due to the bar and/or spiral arms) are associated with families of periodic

  13. Small scale substructure, collapse time and dynamical friction

    CERN Document Server

    Gambera, M

    1996-01-01

    We solve numerically the equations of motion for the collapse of a shell of baryonic matter, made of galaxies and substructure of $ 10^{6} M_{\\odot} \\div 10^{9} M_{\\odot}$, taking into account the dynamical friction and the parameters on which it depends: the peaks' height $\

  14. Substructural Identification of Flexural Rigidity for Beam-Like Structures

    Directory of Open Access Journals (Sweden)

    Ki-Young Koo

    2015-01-01

    Full Text Available This study proposes a novel substructural identification method based on the Bernoulli-Euler beam theory with a single variable optimization scheme to estimate the flexural rigidity of a beam-like structure such as a bridge deck, which is one of the major structural integrity indices of a structure. In ordinary bridges, the boundary condition of a superstructure can be significantly altered by aging and environmental variations, and the actual boundary conditions are generally unknown or difficult to be estimated correctly. To efficiently bypass the problems related to boundary conditions, a substructural identification method is proposed to evaluate the flexural rigidity regardless of the actual boundary conditions by isolating an identification region within the internal substructure. The proposed method is very simple and effective as it utilizes the single variable optimization based on the transfer function formulated utilizing Bernoulli Euler beam theory for the inverse analysis to obtain the flexural rigidity. This novel method is also rigorously investigated by applying it for estimating the flexural rigidity of a simply supported beam model with different boundary conditions, a concrete plate-girder bridge model with different length of an internal substructure, a cantilever-type wind turbine tower structure with different type of excitation, and a steel box-girder bridge model with internal structural damages.

  15. New Developments for Jet Substructure Reconstruction in CMS

    CERN Document Server

    CMS Collaboration

    2017-01-01

    We present Monte Carlo based studies showcasing several developments for jet substructure reconstruction in CMS. This include Quark/Gluon tagging algorithms using Boosted Decision Trees and Deep Neural Networks, the XCone jet clustering algorithm and the Boosted Event Shape Tagger (BEST).

  16. Substructure in the Stellar Halos of the Aquarius Simulations

    NARCIS (Netherlands)

    Helmi, Amina; Cooper, A. P.; White, S. D. M.; Cole, S.; Frenk, C. S.; Navarro, J. F.

    2011-01-01

    We characterize the substructure in the simulated stellar halos of Cooper et al. which were formed by the disruption of satellite galaxies within the cosmological N-body simulations of galactic halos of the Aquarius project. These stellar halos exhibit a wealth of tidal features: broad overdensities

  17. Ancient substructure in early mtDNA lineages of southern Africa.

    Science.gov (United States)

    Barbieri, Chiara; Vicente, Mário; Rocha, Jorge; Mpoloka, Sununguko W; Stoneking, Mark; Pakendorf, Brigitte

    2013-02-07

    Among the deepest-rooting clades in the human mitochondrial DNA (mtDNA) phylogeny are the haplogroups defined as L0d and L0k, which are found primarily in southern Africa. These lineages are typically present at high frequency in the so-called Khoisan populations of hunter-gatherers and herders who speak non-Bantu languages, and the early divergence of these lineages led to the hypothesis of ancient genetic substructure in Africa. Here we update the phylogeny of the basal haplogroups L0d and L0k with 500 full mtDNA genome sequences from 45 southern African Khoisan and Bantu-speaking populations. We find previously unreported subhaplogroups and greatly extend the amount of variation and time-depth of most of the known subhaplogroups. Our major finding is the definition of two ancient sublineages of L0k (L0k1b and L0k2) that are present almost exclusively in Bantu-speaking populations from Zambia; the presence of such relic haplogroups in Bantu speakers is most probably due to contact with ancestral pre-Bantu populations that harbored different lineages than those found in extant Khoisan. We suggest that although these populations went extinct after the immigration of the Bantu-speaking populations, some traces of their haplogroup composition survived through incorporation into the gene pool of the immigrants. Our findings thus provide evidence for deep genetic substructure in southern Africa prior to the Bantu expansion that is not represented in extant Khoisan populations. Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  18. Evolutionarily conserved substrate substructures for automated annotation of enzyme superfamilies.

    Directory of Open Access Journals (Sweden)

    Ranyee A Chiang

    Full Text Available The evolution of enzymes affects how well a species can adapt to new environmental conditions. During enzyme evolution, certain aspects of molecular function are conserved while other aspects can vary. Aspects of function that are more difficult to change or that need to be reused in multiple contexts are often conserved, while those that vary may indicate functions that are more easily changed or that are no longer required. In analogy to the study of conservation patterns in enzyme sequences and structures, we have examined the patterns of conservation and variation in enzyme function by analyzing graph isomorphisms among enzyme substrates of a large number of enzyme superfamilies. This systematic analysis of substrate substructures establishes the conservation patterns that typify individual superfamilies. Specifically, we determined the chemical substructures that are conserved among all known substrates of a superfamily and the substructures that are reacting in these substrates and then examined the relationship between the two. Across the 42 superfamilies that were analyzed, substantial variation was found in how much of the conserved substructure is reacting, suggesting that superfamilies may not be easily grouped into discrete and separable categories. Instead, our results suggest that many superfamilies may need to be treated individually for analyses of evolution, function prediction, and guiding enzyme engineering strategies. Annotating superfamilies with these conserved and reacting substructure patterns provides information that is orthogonal to information provided by studies of conservation in superfamily sequences and structures, thereby improving the precision with which we can predict the functions of enzymes of unknown function and direct studies in enzyme engineering. Because the method is automated, it is suitable for large-scale characterization and comparison of fundamental functional capabilities of both characterized

  19. Identification of genetic outliers due to sub-structure and cryptic relationships.

    Science.gov (United States)

    Schlauch, Daniel; Fier, Heide; Lange, Christoph

    2017-02-22

    In order to minimize the effects of genetic confounding on the analysis of high-throughput genetic association studies, e.g. (whole-genome) sequencing (WGS) studies, genome-wide association studies (GWAS), etc., we propose a general framework to assess and to test formally for genetic heterogeneity among study subjects. As the approach fully utilizes the recent ancestor information captured by rare variants, it is especially powerful in WGS studies. Even for relatively moderate sample sizes, the proposed testing framework is able to identify study subjects that are genetically too similar, e.g cryptic relationships, or that are genetically too different, e.g. population substructure. The approach is computationally fast, enabling the application to whole-genome sequencing data, and straightforward to implement. Simulation studies illustrate the overall performance of our approach. In an application to the 1000 Genomes Project, we outline an analysis/cleaning pipeline that utilizes our approach to formally assess whether study subjects are related and whether population substructure is present. In the analysis of the 1000 Genomes Project data, our approach revealed subjects that are most likely related, but had previously passed standard qc-filters. An implementation of our method, Similarity Test for Estimating Genetic Outliers (STEGO), is available in the R package stego from Github at https://github.com/dschlauch/stego . dschlauch@fas.harvard.edu. Supplementary data are available at Bioinformatics online.

  20. Hidden attractors in dynamical systems

    Science.gov (United States)

    Dudkowski, Dawid; Jafari, Sajad; Kapitaniak, Tomasz; Kuznetsov, Nikolay V.; Leonov, Gennady A.; Prasad, Awadhesh

    2016-06-01

    Complex dynamical systems, ranging from the climate, ecosystems to financial markets and engineering applications typically have many coexisting attractors. This property of the system is called multistability. The final state, i.e., the attractor on which the multistable system evolves strongly depends on the initial conditions. Additionally, such systems are very sensitive towards noise and system parameters so a sudden shift to a contrasting regime may occur. To understand the dynamics of these systems one has to identify all possible attractors and their basins of attraction. Recently, it has been shown that multistability is connected with the occurrence of unpredictable attractors which have been called hidden attractors. The basins of attraction of the hidden attractors do not touch unstable fixed points (if exists) and are located far away from such points. Numerical localization of the hidden attractors is not straightforward since there are no transient processes leading to them from the neighborhoods of unstable fixed points and one has to use the special analytical-numerical procedures. From the viewpoint of applications, the identification of hidden attractors is the major issue. The knowledge about the emergence and properties of hidden attractors can increase the likelihood that the system will remain on the most desirable attractor and reduce the risk of the sudden jump to undesired behavior. We review the most representative examples of hidden attractors, discuss their theoretical properties and experimental observations. We also describe numerical methods which allow identification of the hidden attractors.

  1. New forms of sampling for minority and hidden populations: respondent samples conducted in a south american immigrant population [Nuevas formas de muestreo para minorías y poblaciones ocultas: muestras por encuestado conducido en una población de inmigrantes sudamericanos

    Directory of Open Access Journals (Sweden)

    José Manuel Cárdenas Castro

    2012-06-01

    Full Text Available The Respondent-Driven Sampling (RDS is a method of sampling for hidden or hard-to-reach populations. This is a procedure for estimating the repre- sentativeness of the sample in those groups that is unknow the sampling frame. This study presents both the theoretical description of this form of sampling as the report of its practical application in the case of ethnic minorities (immigrants Bolivians, Peruvians and Colombians in northern Chile. The study started with 8 seeds and recruited a total sample of 109 people from Colombia, Peru and Bolivia. The information resulting from the procedure RDS reports a similar pattern of recruitment for men and women, reflecting the sizes of the networks of both groups did not differ significantly.

  2. Managing Hidden Costs of Offshoring

    DEFF Research Database (Denmark)

    Larsen, Marcus M.; Pedersen, Torben

    2014-01-01

    This chapter investigates the concept of the ‘hidden costs’ of offshoring, i.e. unexpected offshoring costs exceeding the initially expected costs. Due to the highly undefined nature of these costs, we position our analysis towards the strategic responses of firms’ realisation of hidden costs....... In this regard, we argue that a major response to the hidden costs of offshoring is the identification and utilisation of strategic mechanisms in the organisational design to eventually achieving system integration in a globally dispersed and disaggregated organisation. This is heavily moderated by a learning...

  3. KINEMATIC AND SPATIAL SUBSTRUCTURE IN NGC 2264

    Energy Technology Data Exchange (ETDEWEB)

    Tobin, John J. [Hubble Fellow, National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Hartmann, Lee; Hsu, Wen-Hsin; Mateo, Mario [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Fűrész, Gabor, E-mail: tobin@strw.leidenuniv.nl [Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2015-04-15

    We present an expanded kinematic study of the young cluster NGC 2264 based upon optical radial velocities measured using multi-fiber echelle spectroscopy at the 6.5 m MMT and Magellan telescopes. We report radial velocities for 695 stars, of which approximately 407 stars are confirmed or very likely members. Our results more than double the number of members with radial velocities from Fűrész et al., resulting in a much better defined kinematic relationship between the stellar population and the associated molecular gas. In particular, we find that there is a significant subset of stars that are systematically blueshifted with respect to the molecular ({sup 13}CO) gas. The detection of Lithium absorption and/or infrared excesses in this blueshifted population suggests that at least some of these stars are cluster members; we suggest some speculative scenarios to explain their kinematics. Our results also more clearly define the redshifted population of stars in the northern end of the cluster; we suggest that the stellar and gas kinematics of this region are the result of a bubble driven by the wind from O7 star S Mon. Our results emphasize the complexity of the spatial and kinematic structure of NGC 2264, important for eventually building up a comprehensive picture of cluster formation.

  4. Variational Infinite Hidden Conditional Random Fields

    NARCIS (Netherlands)

    Bousmalis, Konstantinos; Zafeiriou, Stefanos; Morency, Louis-Philippe; Pantic, Maja; Ghahramani, Zoubin

    2015-01-01

    Hidden conditional random fields (HCRFs) are discriminative latent variable models which have been shown to successfully learn the hidden structure of a given classification problem. An Infinite hidden conditional random field is a hidden conditional random field with a countably infinite number of

  5. Floating substructure flexibility of large-volume 10MW offshore wind turbine platforms in dynamic calculations

    Science.gov (United States)

    Borg, Michael; Melchior Hansen, Anders; Bredmose, Henrik

    2016-09-01

    Designing floating substructures for the next generation of 10MW and larger wind turbines has introduced new challenges in capturing relevant physical effects in dynamic simulation tools. In achieving technically and economically optimal floating substructures, structural flexibility may increase to the extent that it becomes relevant to include in addition to the standard rigid body substructure modes which are typically described through linear radiation-diffraction theory. This paper describes a method for the inclusion of substructural flexibility in aero-hydro-servo-elastic dynamic simulations for large-volume substructures, including wave-structure interactions, to form the basis of deriving sectional loads and stresses within the substructure. The method is applied to a case study to illustrate the implementation and relevance. It is found that the flexible mode is significantly excited in an extreme event, indicating an increase in predicted substructure internal loads.

  6. Hidden Statistics of Schroedinger Equation

    Science.gov (United States)

    Zak, Michail

    2011-01-01

    Work was carried out in determination of the mathematical origin of randomness in quantum mechanics and creating a hidden statistics of Schr dinger equation; i.e., to expose the transitional stochastic process as a "bridge" to the quantum world. The governing equations of hidden statistics would preserve such properties of quantum physics as superposition, entanglement, and direct-product decomposability while allowing one to measure its state variables using classical methods.

  7. Microgenetic analysis of hidden figures

    OpenAIRE

    Marković Slobodan S.; Gvozdenović Vasilije P.

    2006-01-01

    In this study the phenomenological and processual aspects of the perception of hidden figures were compared. The question was whether the more probable percepts of hidden figures, compared to the less probable percepts, were generated in earlier stages of the perceptual process. In the pilot study the subjects were asked to say what they see in a complex linear pattern. The three most frequent and the three least frequent perceptual descriptions were selected. In the experiment the microgenes...

  8. The Hidden Subgroup Problem

    CERN Document Server

    Wang, Frédéric

    2010-01-01

    We give an overview of the Hidden Subgroup Problem (HSP) as of July 2010, including new results discovered since the survey of arXiv:quant-ph/0411037v1. We recall how the problem provides a framework for efficient quantum algorithms and present the standard methods based on coset sampling. We study the Dihedral and Symmetric HSPs and how they relate to hard problems on lattices and graphs. Finally, we conclude with the known solutions and techniques, describe connections with efficient algorithms as well as miscellaneous variants of HSP. We also bring various contributions to the topic. We show that in theory, we can solve HSP over a given group inductively: the base case is solving HSP over its simple factor groups and the inductive step is building efficient oracles over a normal subgroup N and over the factor group G/N. We apply this analysis to the Dedekindian HSP to get an alternative abelian HSP algorithm based on a change of the underlying group. We also propose a quotient reduction by the normal group...

  9. Managing Hidden Costs of Offshoring

    DEFF Research Database (Denmark)

    Larsen, Marcus M.; Pedersen, Torben

    2014-01-01

    This chapter investigates the concept of the ‘hidden costs’ of offshoring, i.e. unexpected offshoring costs exceeding the initially expected costs. Due to the highly undefined nature of these costs, we position our analysis towards the strategic responses of firms’ realisation of hidden costs. In......-by-doing process, where hidden costs motivate firms and their employees to search for new and better knowledge on how to successfully manage the organisation. We illustrate this thesis based on the case of the LEGO Group.......This chapter investigates the concept of the ‘hidden costs’ of offshoring, i.e. unexpected offshoring costs exceeding the initially expected costs. Due to the highly undefined nature of these costs, we position our analysis towards the strategic responses of firms’ realisation of hidden costs....... In this regard, we argue that a major response to the hidden costs of offshoring is the identification and utilisation of strategic mechanisms in the organisational design to eventually achieving system integration in a globally dispersed and disaggregated organisation. This is heavily moderated by a learning...

  10. The Hidden Costs of Offshoring

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus; Manning, Stephan; Pedersen, Torben

    2011-01-01

    This study seeks to explain hidden costs of offshoring, i.e. unexpected costs resulting from the relocation of business tasks and activities outside the home country. We develop a model that highlights the role of complexity, design orientation and experience in explaining hidden costs of offshor...... of our study is to suggest how hidden costs of offshoring can be mitigated through an explicit orientation towards improving organizational processes and structures as well as experience with offshoring.......This study seeks to explain hidden costs of offshoring, i.e. unexpected costs resulting from the relocation of business tasks and activities outside the home country. We develop a model that highlights the role of complexity, design orientation and experience in explaining hidden costs...... of offshoring. Specifically, we propose that hidden costs can be explained by the combination of increasing structural, operational and social complexity of offshoring activities. In addition, we suggest that firm orientation towards organizational design as part of an offshoring strategy and offshoring...

  11. Towards an understanding of the correlations in jet substructure

    Energy Technology Data Exchange (ETDEWEB)

    Adams, D. [Brookhaven National Laboratory, Upton, NY (United States); Arce, A. [Duke University, Durham, NC (United States); Asquith, L. [University of Sussex, Brighton (United Kingdom); Backovic, M. [CP3, Universite catholique du Louvain, Louvain-la-Neuve (Belgium); Barillari, T.; Menke, S. [Max-Planck-Institute fuer Physik, Munich (Germany); Berta, P. [Charles University in Prague, FMP, Prague (Czech Republic); Bertolini, D. [University of California, Berkeley, CA (United States); Buckley, A.; Ferrando, J.; Pollard, C. [University of Glasgow, G12 8QQ (United Kingdom); Butterworth, J.; Cooper, B. [University College London, WC1E 6BT (United Kingdom); Camacho Toro, R.C.; Picazio, A. [University of Geneva, Geneva 4 (Switzerland); Caudron, J.; El Hedri, S.; Masetti, L. [Universitaet Mainz (Germany); Chien, Y.T.; Hornig, A.; Lee, C. [Los Alamos National Laboratory, Los Alamos, NM (United States); Cogan, J.; Nachman, B.; Nef, P.; Schwartzman, A.; Strauss, E.; Swiatlowski, M. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Curtin, D. [University of Maryland, College Park, MD (United States); Debenedetti, C. [University of California, Santa Cruz, CA (United States); Dolen, J.; Rappoccio, S. [University at Buffalo, Buffalo, NY (United States); Eklund, M.; Embry, T.; Johns, K.; Lampl, W.; Leone, R.; Loch, P.; O' Grady, F.T.; Rutherfoord, J.; Veatch, J. [University of Arizona, Tucson, AZ (United States); Ellis, S.D. [University of Washington, Seattle, WA (United States); Ferencek, D. [Rutgers University, Piscataway, NJ (United States); Fleischmann, S. [Bergische Universitaet Wuppertal, Wuppertal (Germany); Freytsis, M.; Lopez Mateos, D.; Schwartz, M.D. [Harvard University, Cambridge, MA (United States); Giulini, M.; Sosa Corral, D.E. [Universitaet Heidelberg, Heidelberg (Germany); Han, Z.; Soper, D. [University of Oregon, Eugene, OR (United States); Hare, D.; Mishra, K.; Tran, N.V. [Fermi National Accelerator Laboratory, Batavia, IL (United States); Harris, P.; Potter-Landua, B.; Potter, C.; Thomas, C.; Young, C. [CERN, Geneva 23 (Switzerland); Hinzmann, A. [Universitaet Zuerich, Zurich (Switzerland); Hoing, R.; Kogler, R.; Marchesini, I.; Usai, E. [Universitaet Hamburg, Hamburg (Germany); Jankowiak, M. [New York University, New York, NY (United States); Kasieczka, G. [ETH Zuerich, Zurich (Switzerland); Larkoski, A.J.; Marzani, S.; Thaler, J. [Massachusetts Institute of Technology, Cambridge, MA (United States); Lou, H.K. [Princeton University, Princeton, NJ (United States); Low, M.; Miller, D.W. [University of Chicago, Zurich, IL (United States); Maksimovic, P. [Johns Hopkins University, Baltimore, MD (United States); McCarthy, R. [YITP, Stony Brook University, Stony Brook, NY (United States); Ovcharova, A. [University of California, Berkeley National Laboratory, Berkeley, CA (United States); Rojo, J.; Tseng, J. [University of Oxford, Oxford (United Kingdom); Salam, G.P. [CERN, Geneva 23 (Switzerland); LPTHE, UPMC Univ. Paris 6 and CNRS UMR, Paris (France); Schabinger, R.M. [Universidad Autonoma de Madrid, Madrid (Spain); Shuve, B. [Perimeter Institute for Theoretical Physics, ON (Canada); Sinervo, P. [University of Toronto, Toronto, ON (Canada); Spannowsky, M. [University of Durham, IPPP, Durham (United Kingdom); Thompson, E. [Columbia University, New York, NY (United States); Valery, L. [LPC Clermont-Ferrand, Aubiere Cedex (France); Vos, M. [Instituto de Fisica Corpuscular, IFIC/CSIC-UVEG, Valencia (Spain); Waalewijn, W. [University of Amsterdam, Amsterdam (Netherlands); Wacker, J. [Stanford Institute for Theoretical Physics, Stanford, CA (United States)

    2015-09-15

    Over the past decade, a large number of jet substructure observables have been proposed in the literature, and explored at the LHC experiments. Such observables attempt to utilize the internal structure of jets in order to distinguish those initiated by quarks, gluons, or by boosted heavy objects, such as top quarks and W bosons. This report, originating from and motivated by the BOOST2013 workshop, presents original particle-level studies that aim to improve our understanding of the relationships between jet substructure observables, their complementarity, and their dependence on the underlying jet properties, particularly the jet radius and jet transverse momentum. This is explored in the context of quark/gluon discrimination, boosted W boson tagging and boosted top quark tagging. (orig.)

  12. Towards an Understanding of the Correlations in Jet Substructure

    CERN Document Server

    Adams, D; Asquith, L.; Backovic, M.; Barillari, T.; Berta, P.; Bertolini, D.; Buckley, A.; Butterworth, J.; Camacho Toro, R.C.; Caudron, J.; Chien, Y.T.; Cogan, J.; Cooper, B.; Curtin, D.; Debenedetti, C.; Dolen, J.; Eklund, M.; El Hedri, S.; Ellis, S.D.; Embry, T.; Ferencek, D.; Ferrando, J.; Fleischmann, S.; Freytsis, M.; Giulini, M.; Han, Z.; Hare, D.; Harris, P.; Hinzmann, A.; Hoing, R.; Hornig, A.; Jankowiak, M.; Johns, K.; Kasieczka, G.; Kogler, R.; Lampl, W.; Larkoski, A.J.; Lee, C.; Leone, R.; Loch, P.; Lopez Mateos, D.; Lou, H.K.; Low, M.; Maksimovic, P.; Marchesini, I.; Marzani, S.; Masetti, L.; McCarthy, R.; Menke, S.; Miller, D.W.; Mishra, K.; Nachman, B.; Nef, P.; O'Grady, F.T.; Ovcharova, A.; Picazio, A.; Pollard, C.; Potter-Landua, B.; Potter, C.; Rappoccio, S.; Rojo, J.; Rutherfoord, J.; Salam, G.P.; Schabinger, R.M.; Schwartzman, A.; Schwartz, M.D.; Shuve, B.; Sinervo, P.; Soper, D.; Sosa Corral, D.E.; Spannowsky, M.; Strauss, E.; Swiatlowski, M.; Thaler, J.; Thomas, C.; Thompson, E.; Tran, N.V.; Tseng, J.; Usai, E.; Valery, L.; Veatch, J.; Vos, M.; Waalewijn, W.; Wacker, J.; Young, C.

    2015-01-01

    Over the past decade, a large number of jet substructure observables have been proposed in the literature, and explored at the LHC experiments. Such observables attempt to utilize the internal structure of jets in order to distinguish those initiated by quarks, gluons, or by boosted heavy objects, such as top quarks and W bosons. This report, originating from and motivated by the BOOST2013 workshop, presents original particle-level studies that aim to improve our understanding of the relationships between jet substructure observables, their complementarity, and their dependence on the underlying jet properties, particularly the jet radius and jet transverse momentum. This is explored in the context of quark/gluon discrimination, boosted W boson tagging and boosted top quark tagging.

  13. Constraining the Milky Way potential using the dynamical kinematic substructures

    Directory of Open Access Journals (Sweden)

    Antoja T.

    2012-02-01

    Full Text Available We present a method to constrain the potential of the non-axisymmetric components of the Galaxy using the kinematics of stars in the solar neighborhood. The basic premise is that dynamical substructures in phase-space (i.e. due to the bar and/or spiral arms are associated with families of periodic or irregular orbits, which may be easily identified in orbital frequency space. We use the “observed” positions and velocities of stars as initial conditions for orbital integrations in a variety of gravitational potentials. We then compute their characteristic frequencies, and study the structure present in the frequency maps. We find that the distribution of dynamical substructures in velocity- and frequency-space is best preserved when the integrations are performed in the “true” gravitational potential.

  14. Searches for Exotic Physics in ATLAS using Substructure Techniques

    CERN Document Server

    Behr, Janna Katharina; The ATLAS collaboration

    2017-01-01

    The significant increase of the centre-of-mass energy of the Large Hadron Collider (LHC) from 8 to 13 TeV has allowed the LHC experiments to explore previously inaccessible kinematic regimes in their search for phenomena beyond the Standard Model. The sensitivity of these searches depends crucially on the efficient reconstruction and identification of hadronic decays of highly energetic (boosted) objects, the decay products of which are typically collimated into a single large jet with a characteristic substructure. In this contribution, the searches conducted by the ATLAS experiment on data recorded during 2015 and 2016 that rely on jet substructure techniques to identify signatures of interest are reviewed. A particular emphasis is placed on recent developments in the rapidly evolving field of boosted object tagging.

  15. Tracing the Cosmic Web substructure with Lagrangian submanifold

    CERN Document Server

    Shandarin, Sergei F

    2014-01-01

    A new computational paradigm for the analysis of substructure of the Cosmic Web in cosmological cold dark matter simulations is proposed. We introduce a new data-field --- the flip-flop field ---which carries wealth of information about the history and dynamics of the structure formation in the universe. The flip-flop field is an ordered data set in Lagrangian space representing the number of turns inside out sign reversals of an elementary volume of each collisionless fluid element represented by a computational particle in a N-body simulation. This field is computed using the Lagrangian submanifold, i.e. the three-dimensional dark matter sheet in the six-dimensional space formed by three Lagrangian and three Eulerian coordinates of the simulation particles. It is demonstrated that the very rich substructure of dark matter haloes and the void regions can be reliably and unambiguously recovered from the flip-flop field.

  16. A Unified Approach to Substructuring and Structural Modification Problems

    Directory of Open Access Journals (Sweden)

    Walter D’Ambrogio

    2004-01-01

    Full Text Available Substructures coupling is still an important tool in several applications of modal analysis, especially structural modification and structures assembling. The subject is particularly relevant in virtual prototyping of complex systems and responds to actual industrial needs. This paper analyzes the possibility of assembling together different substructures' models. The important role of rotational DoFs is highlighted, underlying the difficulty of assembling theoretical and experimental models, for which, usually, the rotational DoFs are not available. Expansion techniques can be used to provide this information as well as appropriate modelling of joints. With this information FRF models, modal models and FE models can be appropriately combined together and solutions for several cases of practical interest are presented. The analyzed procedures are tested on purpose-built benchmarks, showing limits and capabilities of each of them.

  17. Searches for Exotic Physics in ATLAS using substructure techniques

    CERN Document Server

    Behr, Janna Katharina; The ATLAS collaboration

    2016-01-01

    The significant increase of the centre-of-mass energy of the Large Hadron Collider (LHC) from 8 to 13 TeV has allowed the experiments at the LHC to explore previously inaccessible kinematic regimes in their search for phenomena beyond the Standard Model of Particle Physics. The sensitivity of these searches depends crucially on the efficient reconstruction and identification of hadronic decays of highly energetic (boosted) objects, the decay products of which are typically collimated into a single large jet with a characteristic substructure. In this contribution, I review the searches conducted by the ATLAS experiment on data recorded during 2015 and 2016 that rely on substructure techniques to identify signatures of interest. A particular emphasis is placed on recent developments in the rapidly evolving field of boosted object tagging.

  18. Particle Reconstruction at the LHC using Jet Substructure Algorithms

    CERN Document Server

    Rathjens, Denis

    2012-01-01

    The LHC-era with √ s = 7 TeV allows for a new energy-regime to be accessed. Heavy mass-resonances up to 3.5 TeV/c 2 are in reach. If such heavy particles decay hadronically to much lighter Standard Model particles such as top, Z or W, the jets of the decay products have a sizeable probability to be merged into a single jet. The result is a boosted jet with substructure. This diploma thesis deals with the phenomena of boosted jets, algorithms to distinguish substructure in these jets from normal hadronization and methods to further improve searches with boosted jets. The impact of such methods is demonstrated in an example analysis of a Z’→ tt¯-scenario on 2 fb −1 of data.

  19. Stick-slip substructure in rapid tape peeling

    KAUST Repository

    Thoroddsen, Sigurdur T.

    2010-10-15

    The peeling of adhesive tape is known to proceed with a stick-slip mechanism and produces a characteristic ripping sound. The peeling also produces light and when peeled in a vacuum, even X-rays have been observed, whose emissions are correlated with the slip events. Here we present direct imaging of the detachment zone when Scotch tape is peeled off at high speed from a solid surface, revealing a highly regular substructure, during the slip phase. The typical 4-mm-long slip region has a regular substructure of transverse 220 μm wide slip bands, which fracture sideways at speeds over 300 m/s. The fracture tip emits waves into the detached section of the tape at ∼100 m/s, which promotes the sound, so characteristic of this phenomenon.

  20. Trans-Dimensional Bayesian Inference for Gravitational Lens Substructures

    CERN Document Server

    Brewer, Brendon J; Lewis, Geraint F

    2015-01-01

    We introduce a Bayesian solution to the problem of inferring the density profile of strong gravitational lenses when the lens galaxy may contain multiple dark or faint substructures. The source and lens models are based on a superposition of an unknown number of non-negative basis functions (or "blobs") whose form was chosen with speed as a primary criterion. The prior distribution for the blobs' properties is specified hierarchically, so the mass function of substructures is a natural output of the method. We use reversible jump Markov Chain Monte Carlo (MCMC) within Diffusive Nested Sampling (DNS) to sample the posterior distribution and evaluate the marginal likelihood of the model, including the summation over the unknown number of blobs in the source and the lens. We demonstrate the method on a simulated data set with a single substructure, which is recovered well with moderate uncertainties. We also apply the method to the g-band image of the "Cosmic Horseshoe" system, and find some hints of potential s...

  1. Abell 2744: Too much substructure for Lambda CDM?

    CERN Document Server

    Schwinn, J; Baugh, C M; Bartelmann, M; Eckert, D; Harvey, D; Natarajan, P; Massey, R

    2016-01-01

    The massive substructures found in Abell 2744 by Jauzac et al. (2016) present a challenge to the cold dark matter paradigm due to their number and proximity to the cluster centre. We use one of the biggest N-body simulations, the Millennium XXL, to investigate the substructure in a large sample of massive dark matter haloes. A range of effects which influence the comparison with the observations is considered, extending the preliminary evaluation carried out by Jauzac et al. (2016). There are many tens of haloes in the simulation with a total mass comparable with or larger than that of Abell 2744. However, we find no haloes with a number and distribution of massive substructures (> 5 10^13 Msun) that is close to that inferred from the observations of Abell 2744. The application of extreme value statistics suggests that we would need a simulation of at least ten times the volume of the Millennium XXL to find a single dark matter halo with a similar internal structure to Abell 2744. Explaining the distribution ...

  2. Stellar Substructures Around the Hercules Dwarf Spheroidal Galaxy

    Science.gov (United States)

    Roderick, T. A.; Jerjen, H.; Mackey, A. D.; Da Costa, G. S.

    2015-05-01

    We present deep g and i band Dark Energy Camera stellar photometry of the Hercules Milky Way satellite galaxy, and its surrounding field, out to a radial distance of 5.4 times the tidal radius. We have identified nine extended stellar substructures associated with the dwarf; preferentially distributed along the major axis of the galaxy. Two significant over-densities lie outside the 95% confidence band for the likely orbital path of the galaxy and appear to be free-floating tidal debris. We estimate the luminosity of the new stellar substructures, and find that approximately the same amount of stellar flux is lying in these extended structures as inside the main body of Hercules. We also analyze the distribution of candidate blue-horizontal-branch stars and find agreement with the alignment of the substructures at a confidence level greater than 98%. Our analysis provides a quantitative demonstration that Hercules is a strongly tidally disrupted system, with noticeable stellar features at least 1.9 kpc away from the galaxy.

  3. THE BOLOCAM GALACTIC PLANE SURVEY. XI. TEMPERATURES AND SUBSTRUCTURE OF GALACTIC CLUMPS BASED ON 350 μM OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Merello, Manuel; Evans II, Neal J. [The University of Texas at Austin, Department of Astronomy, 2515 Speedway, Stop C1400, Austin, TX 78712-1205 (United States); Shirley, Yancy L. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Rosolowsky, Erik [Department of Physics, 4-181 CCIS, University of Alberta, Edmonton, AB T6G 2E1 (Canada); Ginsburg, Adam [European Southern Observatory, ESO Headquarters, Karl-Schwarzschild-Strasse 2, D-95748 Garching bei Munchen (Germany); Bally, John [CASA, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Battersby, Cara; Dunham, Michael M., E-mail: manuel@astro.as.utexas.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 78, Cambridge, MA 02138 (United States)

    2015-05-15

    We present 107 maps of continuum emission at 350 μm from Galactic molecular clumps. Observed sources were mainly selected from the Bolocam Galactic Plane Survey (BGPS) catalog, with three additional maps covering star-forming regions in the outer Galaxy. The higher resolution of the SHARC-II images (8.″5 beam) compared with the 1.1 mm images from BGPS (33″ beam) allowed us to identify a large population of smaller substructures within the clumps. A catalog is presented for the 1386 sources extracted from the 350 μm maps. The color temperature distribution of clumps based on the two wavelengths has a median of 13.3 K and mean of 16.3 ± 0.4 K, assuming an opacity law index of 1.7. For the structures with good determination of color temperatures, the mean ratio of gas temperature, determined from NH{sub 3} observations, to dust color temperature is 0.88 and the median ratio is 0.76. About half the clumps have more than 2 substructures and 22 clumps have more than 10. The fraction of the mass in dense substructures seen at 350 μm compared to the mass of their parental clump is ∼0.19, and the surface densities of these substructures are, on average, 2.2 times those seen in the clumps identified at 1.1 mm. For a well-characterized sample, 88 structures (31%) exceed a surface density of 0.2 g cm{sup −2}, and 18 (6%) exceed 1.0 g cm{sup −2}, thresholds for massive star formation suggested by theorists.

  4. Stargate of the Hidden Multiverse

    Directory of Open Access Journals (Sweden)

    Alexander Antonov

    2016-02-01

    Full Text Available Concept of Monoverse, which corresponds to the existing broad interpretation of the second postulate of the special theory of relativity, is not consistent with the modern astrophysical reality — existence of the dark matter and the dark energy, the total mass-energy of which is ten times greater than the mass-energy of the visible universe (which has been considered as the entire universe until very recent . This concept does not allow to explain their rather unusual properties — invisibility and lack of baryon content — which would seem to even destroy the very modern understanding of the term ‘matter’. However, all numerous alternative concepts of Multiverses, which have been proposed until today, are unable to explain these properties of the dark matter and dark energy. This article describes a new concept: the concept of the hidden Multiverse and hidden Supermultiverse, which mutual invisibility of parallel universes is explained by the physical reality of imaginary numbers. This concept completely explains the phenomenon of the dark matter and the dark energy. Moreover, it is shown that the dark matter and the dark energy are the experimental evidence for the existence of the hidden Multiverse. Described structure of the hidden Multiverse is fully consistent with the data obtained by the space stations WMAP and Planck. An extremely important property of the hidden Multiverse is an actual possibility of its permeation through stargate located on the Earth.

  5. Hidden photons in connection to dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Andreas, Sarah; Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Goodsell, Mark D. [CPhT, Ecole Polytechnique, Palaiseau (France)

    2013-06-15

    Light extra U(1) gauge bosons, so called hidden photons, which reside in a hidden sector have attracted much attention since they are a well motivated feature of many scenarios beyond the Standard Model and furthermore could mediate the interaction with hidden sector dark matter.We review limits on hidden photons from past electron beam dump experiments including two new limits from such experiments at KEK and Orsay. In addition, we study the possibility of having dark matter in the hidden sector. A simple toy model and different supersymmetric realisations are shown to provide viable dark matter candidates in the hidden sector that are in agreement with recent direct detection limits.

  6. Hidden worlds in quantum physics

    CERN Document Server

    Gouesbet, Gérard

    2014-01-01

    The past decade has witnessed a resurgence in research and interest in the areas of quantum computation and entanglement. This new book addresses the hidden worlds or variables of quantum physics. Author Gérard Gouesbet studied and worked with a former student of Louis de Broglie, a pioneer of quantum physics. His presentation emphasizes the history and philosophical foundations of physics, areas that will interest lay readers as well as professionals and advanced undergraduate and graduate students of quantum physics. The introduction is succeeded by chapters offering background on relevant concepts in classical and quantum mechanics, a brief history of causal theories, and examinations of the double solution, pilot wave, and other hidden-variables theories. Additional topics include proofs of possibility and impossibility, contextuality, non-locality, classification of hidden-variables theories, and stochastic quantum mechanics. The final section discusses how to gain a genuine understanding of quantum mec...

  7. Hidden Variables or Positive Probabilities?

    CERN Document Server

    Rothman, T; Rothman, Tony

    2001-01-01

    Despite claims that Bell's inequalities are based on the Einstein locality condition, or equivalent, all derivations make an identical mathematical assumption: that local hidden-variable theories produce a set of positive-definite probabilities for detecting a particle with a given spin orientation. The standard argument is that because quantum mechanics assumes that particles are emitted in a superposition of states the theory cannot produce such a set of probabilities. We examine a paper by Eberhard who claims to show that a generalized Bell inequality, the CHSH inequality, can be derived solely on the basis of the locality condition, without recourse to hidden variables. We point out that he nonetheless assumes a set of positive-definite probabilities, which supports the claim that hidden variables or "locality" is not at issue here, positive-definite probabilities are. We demonstrate that quantum mechanics does predict a set of probabilities that violate the CHSH inequality; however these probabilities ar...

  8. Measuring the power spectrum of dark matter substructure using strong gravitational lensing

    CERN Document Server

    Hezaveh, Yashar; Holder, Gilbert; Kisner, Theodore; Kuhlen, Michael

    2014-01-01

    In recent years, it has become possible to detect individual dark matter subhalos near strong gravitational lenses. Typically, only the most massive subhalos in the strong lensing region may be detected this way. In this work, we show that strong lenses may also be used to constrain the much more numerous population of lower mass subhalos that are too small to be detected individually. In particular, we show that the power spectrum of projected density fluctuations in galaxy halos can be measured using strong gravitational lensing. We develop the mathematical framework of power spectrum estimation, and test our method on mock observations. We use our results to determine the types of observations required to measure the substructure power spectrum with high significance. We predict that deep observations with current facilities (in particular ALMA) can measure this power spectrum, placing strong constraints on the abundance of dark matter subhalos and the underlying particle nature of dark matter.

  9. The SLUGGS Survey: Globular cluster system kinematics and substructure in NGC 4365

    CERN Document Server

    Blom, Christina; Brodie, Jean P; Foster, Caroline; Romanowsky, Aaron J; Spitler, Lee R; Strader, Jay

    2012-01-01

    We present a kinematic analysis of the globular cluster (GC) system of the giant elliptical galaxy NGC 4365 and find several distinct kinematic substructures. This analysis is carried out using radial velocities for 269 GCs, obtained with the DEIMOS instrument on the Keck II telescope as part of the SAGES Legacy Unifying Globulars and Galaxies Survey (SLUGGS). We find that each of the three (formerly identified) GC colour subpopulations reveal distinct rotation properties. The rotation of the green GC subpopulation is consistent with the bulk of NGC 4365's stellar light, which `rolls' about the photometric major axis. The blue and red GC subpopulations show `normal' rotation about the minor axis. We also find that the red GC subpopulation is rotationally dominated beyond 2.5 arcmin (~17 kpc) and that the root mean squared velocity of the green subpopulation declines sharply with radius suggesting a possible bias towards radial orbits relative to the other GC subpopulations. Additionally, we find a population ...

  10. The substructure of a flux transfer event observed by the MMS spacecraft

    Science.gov (United States)

    Hwang, K.-J.; Sibeck, D. G.; Giles, B. L.; Pollock, C. J.; Gershman, D.; Avanov, L.; Paterson, W. R.; Dorelli, J. C.; Ergun, R. E.; Russell, C. T.; Strangeway, R. J.; Mauk, B.; Cohen, I. J.; Torbert, R. B.; Burch, J. L.

    2016-09-01

    On 15 August 2015, MMS (Magnetospheric Multiscale mission), skimming the dusk magnetopause, detected an isolated region of an increased magnetic strength and bipolar Bn, indicating a flux transfer event (FTE). The four spacecraft in a tetrahedron allowed for investigations of the shape and motion of the FTE. In particular, high-resolution particle data facilitated our exploration of FTE substructures and their magnetic connectivity inside and surrounding the FTE. Combined field and plasma observations suggest that the core fields are open, magnetically connected to the northern magnetosphere from which high-energy particles leak; ion "D" distributions characterize the axis of flux ropes that carry old-opened field lines; counterstreaming electrons superposed by parallel-heated components populate the periphery surrounding the FTE; and the interface between the core and draped regions contains a separatrix of newly opened magnetic field lines that emanate from the X line above the FTE.

  11. The Hidden Costs of Offshoring

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus; Manning, Stephan; Pedersen, Torben

    2011-01-01

    experience moderate the relationship between complexity and hidden costs negatively i.e. reduces the cost generating impact of complexity. We develop three hypotheses and test them on comprehensive data from the Offshoring Research Network (ORN). In general, we find support for our hypotheses. A key result...... of offshoring. Specifically, we propose that hidden costs can be explained by the combination of increasing structural, operational and social complexity of offshoring activities. In addition, we suggest that firm orientation towards organizational design as part of an offshoring strategy and offshoring...

  12. Hidden symmetries in jammed systems

    Science.gov (United States)

    Morse, Peter K.; Corwin, Eric I.

    2016-07-01

    There are deep, but hidden, geometric structures within jammed systems, associated with hidden symmetries. These can be revealed by repeated transformations under which these structures lead to fixed points. These geometric structures can be found in the Voronoi tesselation of space defined by the packing. In this paper we examine two iterative processes: maximum inscribed sphere (MIS) inversion and a real-space coarsening scheme. Under repeated iterations of the MIS inversion process we find invariant systems in which every particle is equal to the maximum inscribed sphere within its Voronoi cell. Using a real-space coarsening scheme we reveal behavior in geometric order parameters which is length-scale invariant.

  13. Hidden Crises and Communication : An Interactional Analysis of Hidden Crises

    NARCIS (Netherlands)

    Klarenbeek, Annette

    2011-01-01

    In this paper I describe the ways in which the communication discipline can make a hidden crisis transparent. For this purpose I examine the concept of crisis entrepreneurship from a communication point of view. Using discourse analysis, I analyse the discursive practices of crisis entrepreneurs in

  14. GLAST And Dark Matter Substructure in the Milky Way

    Energy Technology Data Exchange (ETDEWEB)

    Kuhlen, Michael; /Princeton, Inst. Advanced Study; Diemand, Jurg; /UC, Santa Cruz, Astron. Astrophys.; Madau, Piero; /UC, Santa Cruz, Astron. Astrophys. /Garching, Max Planck Inst.

    2011-11-29

    We discuss the possibility of GLAST detecting gamma-rays from the annihilation of neutralino dark matter in the Galactic halo. We have used 'Via Lactea', currently the highest resolution simulation of cold dark matter substructure, to quantify the contribution of subhalos to the annihilation signal. We present a simulated allsky map of the expected gamma-ray counts from dark matter annihilation, assuming standard values of particle mass and cross section. In this case GLAST should be able to detect the Galactic center and several individual subhalos. One of the most exciting discoveries that the Gamma-ray Large Area Space Telescope (GLAST) could make, is the detection of gamma-rays from the annihilation of dark matter (DM). Such a measurement would directly address one of the major physics problems of our time: the nature of the DM particle. Whether or not GLAST will actually detect a DM annihilation signal depends on both unknown particle physics and unknown astrophysics theory. Particle physics uncertainties include the type of particle (axion, neutralino, Kaluza-Klein particle, etc.), its mass, and its interaction cross section. From the astrophysical side it appears that DM is not smoothly distributed throughout the Galaxy halo, but instead exhibits abundant clumpy substructure, in the form of thousands of so-called subhalos. The observability of DM annihilation radiation originating in Galactic DM subhalos depends on their abundance, distribution, and internal properties. Numerical simulations have been used in the past to estimate the annihilation flux from DM substructure, but since the subhalo properties, especially their central density profile, which determines their annihilation luminosity, are very sensitive to numerical resolution, it makes sense to re-examine their contribution with higher resolution simulations.

  15. Floating substructure flexibility of large-volume 10MW offshore wind turbine platforms in dynamic calculations

    DEFF Research Database (Denmark)

    Borg, Michael; Hansen, Anders Melchior; Bredmose, Henrik

    2016-01-01

    to the extent that it becomes relevant to include in addition to the standard rigid body substructure modes which are typically described through linear radiation-diffraction theory. This paper describes a method for the inclusion of substructural flexibility in aero-hydro-servo-elastic dynamic simulations......Designing floating substructures for the next generation of 10MW and larger wind turbines has introduced new challenges in capturing relevant physical effects in dynamic simulation tools. In achieving technically and economically optimal floating substructures, structural flexibility may increase...

  16. Fatigue reassessment for lifetime extension of offshore wind monopile substructures

    Science.gov (United States)

    Ziegler, Lisa; Muskulus, Michael

    2016-09-01

    Fatigue reassessment is required to decide about lifetime extension of aging offshore wind farms. This paper presents a methodology to identify important parameters to monitor during the operational phase of offshore wind turbines. An elementary effects method is applied to analyze the global sensitivity of residual fatigue lifetimes to environmental, structural and operational parameters. Therefore, renewed lifetime simulations are performed for a case study which consists of a 5 MW turbine with monopile substructure in 20 m water depth. Results show that corrosion, turbine availability, and turbulence intensity are the most influential parameters. This can vary strongly for other settings (water depth, turbine size, etc.) making case-specific assessments necessary.

  17. Validation of metabolic pathway databases based on chemical substructure search.

    Science.gov (United States)

    Félix, Liliana; Valiente, Gabriel

    2007-09-01

    Metabolic pathway databases such as KEGG contain information on thousands of biochemical reactions drawn from the biomedical literature. Ensuring consistency of such large metabolic pathways is essential to their proper use. In this paper, we present a new method to determine consistency of an important class of biochemical reactions. Our method exploits the knowledge of the atomic rearrangement pattern in biochemical reactions, to reduce the automatic atom mapping problem to a series of chemical substructure searches between the substrate and the product of a biochemical reaction. As an illustrative application, we describe the exhaustive validation of a substantial portion from the latest release of the KEGG LIGAND database.

  18. Modeling Multiple Risks: Hidden Domain of Attraction

    CERN Document Server

    Mitra, Abhimanyu

    2011-01-01

    Hidden regular variation is a sub-model of multivariate regular variation and facilitates accurate estimation of joint tail probabilities. We generalize the model of hidden regular variation to what we call hidden domain of attraction. We exhibit examples that illustrate the need for a more general model and discuss detection and estimation techniques.

  19. Pentaquark states with hidden charm

    Science.gov (United States)

    Bijker, Roelof

    2017-07-01

    I develop an extension of the usual three-flavor quark model to four flavors (u, d, s and c), and discuss the classification of pentaquark states with hidden charm. This work is motivated by the recent observation of such states by the LHCb Collatoration at CERN.

  20. Microgenetic analysis of hidden figures

    Directory of Open Access Journals (Sweden)

    Marković Slobodan S.

    2006-01-01

    Full Text Available In this study the phenomenological and processual aspects of the perception of hidden figures were compared. The question was whether the more probable percepts of hidden figures, compared to the less probable percepts, were generated in earlier stages of the perceptual process. In the pilot study the subjects were asked to say what they see in a complex linear pattern. The three most frequent and the three least frequent perceptual descriptions were selected. In the experiment the microgenesis of the perception of hidden figures was investigated. The primed matching paradigm and the same-different task were used. In each experiment two types of test figures were contrasted: the more frequent and the less frequent ones. There were two prime types: identical (equal to test figures and complex (the pattern with hidden test figures. The prime duration was varied, 50 ms and 400 ms. The main result indicates that in the case of complex priming the more frequent test figures were processed significantly faster than the less frequent ones in both prime duration conditions. These results suggest that the faster the processing of a figure, the more probable the perceptual generation of this figure.

  1. SHARP - II. Mass structure in strong lenses is not necessarily dark matter substructure: a flux ratio anomaly from an edge-on disc in B1555+375

    Science.gov (United States)

    Hsueh, J.-W.; Fassnacht, C. D.; Vegetti, S.; McKean, J. P.; Spingola, C.; Auger, M. W.; Koopmans, L. V. E.; Lagattuta, D. J.

    2016-11-01

    Gravitational lens flux-ratio anomalies provide a powerful technique for measuring dark matter substructure in distant galaxies. However, before using these flux-ratio anomalies to test galaxy formation models, it is imperative to ascertain that the given anomalies are indeed due to the presence of dark matter substructure and not due to some other component of the lensing galaxy halo or to propagation effects. Here we present the case of CLASS~B1555+375, which has a strong radio-wavelength flux-ratio anomaly. Our high-resolution near-infrared Keck~II adaptive optics imaging and archival Hubble Space Telescope data reveal the lensing galaxy in this system to have a clear edge-on disc component that crosses directly over the pair of images that exhibit the flux-ratio anomaly. We find that simple models that include the disc can reproduce the cm-wavelength flux-ratio anomaly without requiring additional dark matter substructure. Although further studies are required, our results suggest the assumption that all flux-ratio anomalies are due to a population of dark matter sub-haloes may be incorrect, and analyses that do not account for the full complexity of the lens macro-model may overestimate the substructure mass fraction in massive lensing galaxies.

  2. Carotta: Revealing Hidden Confounder Markers in Metabolic Breath Profiles

    Directory of Open Access Journals (Sweden)

    Anne-Christin Hauschild

    2015-06-01

    Full Text Available Computational breath analysis is a growing research area aiming at identifying volatile organic compounds (VOCs in human breath to assist medical diagnostics of the next generation. While inexpensive and non-invasive bioanalytical technologies for metabolite detection in exhaled air and bacterial/fungal vapor exist and the first studies on the power of supervised machine learning methods for profiling of the resulting data were conducted, we lack methods to extract hidden data features emerging from confounding factors. Here, we present Carotta, a new cluster analysis framework dedicated to uncovering such hidden substructures by sophisticated unsupervised statistical learning methods. We study the power of transitivity clustering and hierarchical clustering to identify groups of VOCs with similar expression behavior over most patient breath samples and/or groups of patients with a similar VOC intensity pattern. This enables the discovery of dependencies between metabolites. On the one hand, this allows us to eliminate the effect of potential confounding factors hindering disease classification, such as smoking. On the other hand, we may also identify VOCs associated with disease subtypes or concomitant diseases. Carotta is an open source software with an intuitive graphical user interface promoting data handling, analysis and visualization. The back-end is designed to be modular, allowing for easy extensions with plugins in the future, such as new clustering methods and statistics. It does not require much prior knowledge or technical skills to operate. We demonstrate its power and applicability by means of one artificial dataset. We also apply Carotta exemplarily to a real-world example dataset on chronic obstructive pulmonary disease (COPD. While the artificial data are utilized as a proof of concept, we will demonstrate how Carotta finds candidate markers in our real dataset associated with confounders rather than the primary disease (COPD

  3. Design and Analysis of Jacket Substructures for Offshore Wind Turbines

    Directory of Open Access Journals (Sweden)

    I-Wen Chen

    2016-04-01

    Full Text Available This study focused on investigating various existing types of offshore jacket substructures along with a proposed twisted-tripod jacket type (modified jacket (MJ-structures. The architectures of the three-leg structure, as well as the patented twisted jacket structure motivated the design of the proposed MJ-structures. The dimensions of the structures were designed iteratively using static stress analysis to ensure that all structures had a similar level of load-carrying capability. The numerical global buckling analyses were performed for all structures after the validation by the scaled-down experiments. The local buckling strength of all compressive members was analyzed using the NORSOK standard. The results showed that the proposed MJ-structures possess excellent structural behavior and few structural nodes and components competitive with the patented twisted jacket structures, while still maintaining the advantages of low material usage similar to the three-leg jacket structures. This study provides alternatives for the initial selection and design of offshore wind turbine substructures for green energy applications.

  4. Replaceable Substructures for Efficient Part-Based Modeling

    KAUST Repository

    Liu, Han

    2015-05-01

    A popular mode of shape synthesis involves mixing and matching parts from different objects to form a coherent whole. The key challenge is to efficiently synthesize shape variations that are plausible, both locally and globally. A major obstacle is to assemble the objects with local consistency, i.e., all the connections between parts are valid with no dangling open connections. The combinatorial complexity of this problem limits existing methods in geometric and/or topological variations of the synthesized models. In this work, we introduce replaceable substructures as arrangements of parts that can be interchanged while ensuring boundary consistency. The consistency information is extracted from part labels and connections in the original source models. We present a polynomial time algorithm that discovers such substructures by working on a dual of the original shape graph that encodes inter-part connectivity. We demonstrate the algorithm on a range of test examples producing plausible shape variations, both from a geometric and from a topological viewpoint. © 2015 The Author(s) Computer Graphics Forum © 2015 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.

  5. Residuated lattices an algebraic glimpse at substructural logics

    CERN Document Server

    Galatos, Nikolaos; Kowalski, Tomasz; Ono, Hiroakira

    2007-01-01

    The book is meant to serve two purposes. The first and more obvious one is to present state of the art results in algebraic research into residuated structures related to substructural logics. The second, less obvious but equally important, is to provide a reasonably gentle introduction to algebraic logic. At the beginning, the second objective is predominant. Thus, in the first few chapters the reader will find a primer of universal algebra for logicians, a crash course in nonclassical logics for algebraists, an introduction to residuated structures, an outline of Gentzen-style calculi as well as some titbits of proof theory - the celebrated Hauptsatz, or cut elimination theorem, among them. These lead naturally to a discussion of interconnections between logic and algebra, where we try to demonstrate how they form two sides of the same coin. We envisage that the initial chapters could be used as a textbook for a graduate course, perhaps entitled Algebra and Substructural Logics. As the book progresses the f...

  6. Cold Dark Matter Substructures in Early-Type Galaxy Halos

    CERN Document Server

    Fiacconi, Davide; Potter, Doug; Stadel, Joachim

    2016-01-01

    We present initial results from the "Ponos" zoom-in numerical simulations of dark matter substructures in massive ellipticals. Two very highly resolved dark matter halos with $M_{\\rm vir}=1.2\\times 10^{13}$ $M_{\\odot}$ and $M_{\\rm vir}=6.5\\times 10^{12}$ $M_{\\odot}$ and different ("violent" vs. "quiescent") assembly histories have been simulated down to $z=0$ in a $\\Lambda$CDM cosmology with a total of 921,651,914 and 408,377,544 particles, respectively. Within the virial radius, the total mass fraction in self-bound $M_{\\rm sub}>10^6$ $M_{\\odot}$ subhalos at the present epoch is 15% for the violent host and 16.5% for the quiescent one. At $z=0.7$, these fractions increase to 19 and 33%, respectively, as more recently accreted satellites are less prone to tidal destruction. In projection, the average fraction of surface mass density in substructure at a distance of $R/R_{\\rm vir}=0.02$ ($\\sim 5-10$ kpc) from the two halo centers ranges from 0.6% to $\\gtrsim 2$%, significantly higher than measured in simulatio...

  7. Fossil Group Origins VII. Galaxy substructures in fossil systems

    CERN Document Server

    Zarattini, S; Aguerri, J A L; Boschin, W; Barrena, R; del Burgo, C; Castro-Rodriguez, N; Corsini, E M; D'Onghia, E; Kundert, A; Méndez-Abreu, J; Sánchez-Janssen, R

    2016-01-01

    Fossil groups are expected to be the final product of galaxy merging within galaxy groups. In simulations, they are predicted to assemble their mass at high redshift. This early formation allows for the innermost $M^\\ast$ galaxies to merge into a massive central galaxy. Then, they are expected to maintain their fossil status because of the few interactions with the large-scale structure. In this context, the magnitude gap between the two brightest galaxies of the system is considered a good indicator of its dynamical status. As a consequence, the systems with the largest gaps should be dynamically relaxed. In order to examine the dynamical status of these systems, we systematically analyze, for the first time, the presence of galaxy substructures in a sample of 12 spectroscopically-confirmed fossil systems with redshift $z \\le 0.25$. We apply a number of tests in order to investigate the substructure in fossil systems in the two-dimensional space of projected positions out to $R_{200}$. Moreover, for a subsam...

  8. Detection of a Dark Substructure through Gravitational Imaging

    CERN Document Server

    Vegetti, S; Bolton, A; Treu, T; Gavazzi, R

    2009-01-01

    We report the detection of a dark substructure through direct gravitational imaging - undetected in the HST-WFPC2 F606W image - in the gravitational lens galaxy of SLACS SDSSJ0946+1006 (the "Double Einstein Ring"). The detection is based on a Bayesian grid reconstruction of the two-dimensional surface density of the galaxy inside an annulus around its Einstein radius (few kpc). The detection of a small mass concentration in the surface density maps has a strong statistical significance. We confirm this detection by modeling the system including a parametric mass model with a tidally truncated pseudo-Jaffe density profile; in that case the substructure mass is M_sub=(3.51+-0.15)x10^9 Msun, located at (-0.651+-0.038,1.040+-0.034)'', precisely where also the surface density map shows a strong convergence peak (Bayes factor dlog(E)=-128.0; equivalent to a ~16-sigma detection). The result is robust under substantial changes in the model and the data-set (e.g. PSF, pixel number and scale, source and potential regul...

  9. Identifying hidden sexual bridging communities in Chicago.

    Science.gov (United States)

    Youm, Yoosik; Mackesy-Amiti, Mary Ellen; Williams, Chyvette T; Ouellet, Lawrence J

    2009-07-01

    Bridge populations can play a central role in the spread of human immunodeficiency virus (HIV) by providing transmission links between higher and lower prevalence populations. While social network methods are well suited to the study of bridge populations, analyses tend to focus on dyads (i.e., risk between drug and/or sex partners) and ignore bridges between distinct subpopulations. This study takes initial steps toward moving the analysis of sexual network linkages beyond individual and risk group levels to a community level in which Chicago's 77 community areas are examined as subpopulations for the purpose of identifying potential bridging communities. Of particular interest are "hidden" bridging communities; that is, areas with above-average levels of sexual ties with other areas but whose below-average AIDS prevalence may hide their potential importance for HIV prevention. Data for this analysis came from the first wave of recruiting at the Chicago Sexual Acquisition and Transmission of HIV Cooperative Agreement Program site. Between August 2005 through October 2006, respondent-driven sampling was used to recruit users of heroin, cocaine, or methamphetamine, men who have sex with men regardless of drug use, the sex partners of these two groups, and sex partners of the sex partners. In this cross-sectional study of the sexual transmission of HIV, participants completed a network-focused computer-assisted self-administered interview, which included questions about the geographic locations of sexual contacts with up to six recent partners. Bridging scores for each area were determined using a matrix representing Chicago's 77 community areas and were assessed using two measures: non-redundant ties and flow betweenness. Bridging measures and acquired immunodeficiency syndrome (AIDS) case prevalence rates were plotted for each community area on charts representing four conditions: below-average bridging and AIDS prevalence, below-average bridging and above

  10. Tapping into hidden potential

    Directory of Open Access Journals (Sweden)

    Paula Gould

    2003-09-01

    As the academic year begins, students enrolling at universities worldwide have a treat in store. There is a course on offer that could explain how to cut the cost of street lighting, improve the mobility of an aging population, reduce the amount of waste sent to landfill, speedup electronic communication, and detect the first signs of a biological terrorist attack. No surprises, then, for guessing that this course is materials science and engineering. But teenagers versed in the language of physics, chemistry, biology, and engineering may not have made the connection. And there in lies the root of a possible recruitment problem.

  11. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XIX. TOMOGRAPHY OF MILKY WAY SUBSTRUCTURES IN THE NGVS FOOTPRINT

    Energy Technology Data Exchange (ETDEWEB)

    Lokhorst, Deborah; Starkenburg, Else; Navarro, Julio F. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 1A1, Canada (Canada); McConnachie, Alan W.; Ferrarese, Laura; Côté, Patrick; Gwyn, Stephen D. J. [National Research Council, Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Liu, Chengze [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Peng, Eric W. [Department of Astronomy, Peking University, Beijing 100871 (China); Cuillandre, Jean-Charles [CEA/IRFU/SAP, Laboratoire AIM Paris-Saclay, CNRS/INSU, Université Paris Diderot, Observatoire de Paris, PSL Research University, F-91191 Gif-sur-Yvette Cedex (France); Guhathakurta, Puragra, E-mail: dml@uvic.ca [Department of Astronomy and Astrophysics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2016-03-10

    The Next Generation Virgo Cluster Survey (NGVS) is a deep u*giz survey targeting the Virgo Cluster of galaxies at 16.5 Mpc. This survey provides high-quality photometry over an ∼100 deg{sup 2} region straddling the constellations of Virgo and Coma Berenices. This sightline through the Milky Way is noteworthy in that it intersects two of the most prominent substructures in the Galactic halo: the Virgo overdensity (VOD) and Sagittarius stellar stream (close to its bifurcation point). In this paper, we use deep u*gi imaging from the NGVS to perform tomography of the VOD and Sagittarius stream using main-sequence turnoff (MSTO) stars as a halo tracer population. The VOD, whose centroid is known to lie at somewhat lower declinations (α ∼ 190°, δ ∼ −5°) than is covered by the NGVS, is nevertheless clearly detected in the NGVS footprint at distances between ∼8 and 25 kpc. By contrast, the Sagittarius stream is found to slice directly across the NGVS field at distances between 25 and 40 kpc, with a density maximum at ≃35 kpc. No evidence is found for new substructures beyond the Sagittarius stream, at least out to a distance of ∼90 kpc—the largest distance to which we can reliably trace the halo using MSTO stars. We find clear evidence for a distance gradient in the Sagittarius stream across the ∼30° of sky covered by the NGVS and its flanking fields. We compare our distance measurements along the stream with those predicted by leading stream models.

  12. Nonintentional behavioural responses to psi : hidden targets and hidden observers

    OpenAIRE

    Anderson, Mary-Jane Charlotte

    2012-01-01

    Psi is the phenomenon of apparently responding to or receiving information by means other than the recognised senses. Psi information may influence human behaviour, without the individual intending this or even being aware of it. This thesis seeks to investigate nonintentional behavioural responses to psi. We present five empirical studies that investigated nonintentional behavioural responses to psi information. In each study, the psi information was hidden from participants, ...

  13. Formation of deformation substructures in FCC crystals under the influence of point defect fluxes

    OpenAIRE

    Matveev, M. V.; Selivanikova, Olga Valerievna; Cherepanov, Dmitry Nikolaevich

    2016-01-01

    The article deals with sub-structural transformations in FCC crystals under the influence of point defect fluxes. Different relationships between accumulation of point defects in crystal and substructure transformations, in particular during the process of fragmented dislocation structure formation have been received.

  14. A Comparison of Reduced Order Modeling Techniques Used in Dynamic Substructuring [PowerPoint

    Energy Technology Data Exchange (ETDEWEB)

    Roettgen, Dan [Wisc; Seeger, Benjamin [Stuttgart; Tai, Wei Che [Washington; Baek, Seunghun [Michigan; Dossogne, Tilan [Liege; Allen, Matthew S [Wisc; Kuether, Robert J.; Brake, Matthew Robert; Mayes, Randall L.

    2016-01-01

    Experimental dynamic substructuring is a means whereby a mathematical model for a substructure can be obtained experimentally and then coupled to a model for the rest of the assembly to predict the response. Recently, various methods have been proposed that use a transmission simulator to overcome sensitivity to measurement errors and to exercise the interface between the substructures; including the Craig-Bampton, Dual Craig-Bampton, and Craig-Mayes methods. This work compares the advantages and disadvantages of these reduced order modeling strategies for two dynamic substructuring problems. The methods are first used on an analytical beam model to validate the methodologies. Then they are used to obtain an experimental model for structure consisting of a cylinder with several components inside connected to the outside case by foam with uncertain properties. This represents an exceedingly difficult structure to model and so experimental substructuring could be an attractive way to obtain a model of the system.

  15. A Comparison of Reduced Order Modeling Techniques Used in Dynamic Substructuring.

    Energy Technology Data Exchange (ETDEWEB)

    Roettgen, Dan; Seegar, Ben; Tai, Wei Che; Baek, Seunghun; Dossogne, Tilan; Allen, Matthew; Kuether, Robert J.; Brake, Matthew Robert; Mayes, Randall L.

    2015-10-01

    Experimental dynamic substructuring is a means whereby a mathematical model for a substructure can be obtained experimentally and then coupled to a model for the rest of the assembly to predict the response. Recently, various methods have been proposed that use a transmission simulator to overcome sensitivity to measurement errors and to exercise the interface between the substructures; including the Craig-Bampton, Dual Craig-Bampton, and Craig-Mayes methods. This work compares the advantages and disadvantages of these reduced order modeling strategies for two dynamic substructuring problems. The methods are first used on an analytical beam model to validate the methodologies. Then they are used to obtain an experimental model for structure consisting of a cylinder with several components inside connected to the outside case by foam with uncertain properties. This represents an exceedingly difficult structure to model and so experimental substructuring could be an attractive way to obtain a model of the system.

  16. The LabelHash algorithm for substructure matching

    Directory of Open Access Journals (Sweden)

    Bryant Drew H

    2010-11-01

    Full Text Available Abstract Background There is an increasing number of proteins with known structure but unknown function. Determining their function would have a significant impact on understanding diseases and designing new therapeutics. However, experimental protein function determination is expensive and very time-consuming. Computational methods can facilitate function determination by identifying proteins that have high structural and chemical similarity. Results We present LabelHash, a novel algorithm for matching substructural motifs to large collections of protein structures. The algorithm consists of two phases. In the first phase the proteins are preprocessed in a fashion that allows for instant lookup of partial matches to any motif. In the second phase, partial matches for a given motif are expanded to complete matches. The general applicability of the algorithm is demonstrated with three different case studies. First, we show that we can accurately identify members of the enolase superfamily with a single motif. Next, we demonstrate how LabelHash can complement SOIPPA, an algorithm for motif identification and pairwise substructure alignment. Finally, a large collection of Catalytic Site Atlas motifs is used to benchmark the performance of the algorithm. LabelHash runs very efficiently in parallel; matching a motif against all proteins in the 95% sequence identity filtered non-redundant Protein Data Bank typically takes no more than a few minutes. The LabelHash algorithm is available through a web server and as a suite of standalone programs at http://labelhash.kavrakilab.org. The output of the LabelHash algorithm can be further analyzed with Chimera through a plugin that we developed for this purpose. Conclusions LabelHash is an efficient, versatile algorithm for large-scale substructure matching. When LabelHash is running in parallel, motifs can typically be matched against the entire PDB on the order of minutes. The algorithm is able to identify

  17. Exposing the dead cone effect with jet substructure techniques

    Science.gov (United States)

    Maltoni, Fabio; Selvaggi, Michele; Thaler, Jesse

    2016-09-01

    The dead cone is a well-known effect in gauge theories, where radiation from a charged particle of mass m and energy E is suppressed within an angular size of m /E . This effect is universal as it does not depend on the spin of the particle nor on the nature of the gauge interaction. It is challenging to directly measure the dead cone at colliders, however, since the region of suppressed radiation either is too small to be resolved or is filled by the decay products of the massive particle. In this paper, we propose to use jet substructure techniques to expose the dead cone effect in the strong-force radiation pattern around boosted top quarks at the Large Hadron Collider. Our study shows that with 300 /fb of 13-14 TeV collision data, ATLAS and CMS could obtain the first direct evidence of the dead cone effect and test its basic features.

  18. Performance of boosted object and jet substructure techniques

    CERN Document Server

    Schramm, Steven; The ATLAS collaboration

    2016-01-01

    Hadronic decays of heavy particles with momenta much larger than their mass result in their decay products being reconstructable as a single large ­radius jet. The study of the substructure of these jets allows the separation of these boosted decays with respect to more common jets from light­ quarks and gluons. Several techniques have been developed by the phenomenology and experimental community to identify jets coming from hadronic decays of boosted top quarks, W, Z and Higgs bosons. The performance of several such techniques have been studied in ATLAS using fully­ simulated Monte Carlo events, and validated on data using pure samples of top quarks, W bosons from top decays and dijet events. Results of these studies will be presented for Run 1 as well as Run 2 of the LHC.

  19. Substructure effects on the collapse of density perturbations

    CERN Document Server

    Popolo, A D

    1996-01-01

    We solve numerically the equations of motion for the collapse of a shell of baryonic matter, made of galaxies and substructure of $ 10^{6} M_{\\odot}- 10^{9} M_{\\odot}$, falling into the central regions of a cluster of galaxies taking account of dynamical friction. We calculate the evolution of the expansion parameter, a(t), of the perturbation using a coefficient of dynamical friction, $ \\eta_{0}$, calculated for a perturbation in which clustering is absent and a coefficient $ \\eta_{cl}$ obtained from a clustered one. The effect of the dynamical friction is to slow down the collapse (V. Antonuccio-Delogu \\& S. Colafrancesco 1994, hereafter AC) producing an observable variation of the parameter of expansion of the shell. The effect increases with increasing $ time depends on $ \\eta_{0}$ and $ \\eta_{cl}$. keywords: {cosmology: theory- galaxies: formation}

  20. Decorrelated Jet Substructure Tagging using Adversarial Neural Networks

    CERN Document Server

    CERN. Geneva

    2017-01-01

    We describe a strategy for constructing a neural network jet substructure tagger which powerfully discriminates boosted decay signals while remaining largely uncorrelated with the jet mass. This reduces the impact of systematic uncertainties in background modeling while enhancing signal purity, resulting in improved discovery significance relative to existing taggers. The network is trained using an adversarial strategy, resulting in a tagger that learns to balance classification accuracy with decorrelation. As a benchmark scenario, we consider the case where large-radius jets originating from a boosted Z' decay are discriminated from a background of nonresonant quark and gluon jets. We show that in the presence of systematic uncertainties on the background rate, our adversarially-trained, decorrelated tagger considerably outperforms a conventionally trained neural network, despite having a slightly worse signal-background separation power. We generalize the adversarial training technique to include a paramet...

  1. ATLAS Standard Model Measurements Using Jet Grooming and Substructure

    CERN Document Server

    Ucchielli, Giulia; The ATLAS collaboration

    2017-01-01

    Boosted topologies allow to explore Standard Model processes in kinematical regimes never tested before. In such LHC challenging environments, standard reconstruction techniques quickly hit the wall. Targeting hadronic final states means to properly reconstruct energy and multiplicity of the jets in the event. In order to be able to identify the decay product of boosted objects, i.e. W bosons, $t\\bar{t}$ pairs or Higgs produced in association with $t\\bar{t}$ pairs, ATLAS experiment is currently exploiting several algorithms using jet grooming and jet substructure. This contribution will mainly cover the following ATLAS measurements: $t\\bar{t}$ differential cross section production and jet mass using the soft drop procedure. Standard Model measurements offer the perfect field to test the performances of new jet tagging techniques which will become even more important in the search for new physics in highly boosted topologies.”

  2. Resonance Related Spiral Substructure in a Galactic Gaseous Disk

    CERN Document Server

    Yáñez, Miguel A; Martos, Marco A; Hayes, John C

    2007-01-01

    We use high resolution 2D hydrodynamic simulations to study the formation of spiral substructure in the gaseous disk of a galaxy. The obtained gaseous response is driven by a self-consistent non-axisymmetric potential obtained from an imposed spiral mass distribution. We highlight the importance of ultraharmonic resonances in generating these features. The temporal evolution of the system is followed with the parallel ZEUS-MP code, and we follow the steepening of perturbations induced by the spiral potential until large-scale shocks emerge. These shocks exhibit bifurcations that protrude from the gaseous arms and continue to steepen until new shocks are formed. When the contribution from the spiral potential relative to the axisymmetric background is increased from our default value, spurs protrude from the main arms after several revolutions of the gaseous disk. Such spurs overlap on top of the aforementioned shocks. These results support the hypothesis that a complicated gaseous response can coexist with an...

  3. Substructure drag effects and recrystallization textures in aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Higginson, R. [Univ. of Sheffield (United Kingdom). Dept. of Engineering Materials; Bate, P. [Doncasters plc, Melbourne (United Kingdom)

    1999-03-10

    Many important recrystallization texture components in metals such as aluminium originate from nuclei in which the mobile high-angle boundary exists prior to, or is formed in the early stages of, annealing. Nucleation can then occur by a process known as strain-induced boundary migration (SIBM). It is possible that this process will involve several growing subgrains, and the drag from that substructure can then have a significant effect. A simple model is used to demonstrate how changes in the overall driving force for recrystallization and Zener drag can affect recrystallization textures when SIBM is involved. This is discussed in relation to experimental observations and the evidence for this process is reviewed.

  4. Dynamics of 10 clusters of galaxies with substructures

    Energy Technology Data Exchange (ETDEWEB)

    Lakhchaura, Kiran; Singh, K. P., E-mail: kiran_astro@tifr.res.in [Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India)

    2014-06-01

    We present a detailed Chandra study of a sample of 10 clusters of galaxies selected based on the presence of substructures in their optical images. The X-ray surface brightness maps of most of these clusters show anisotropic morphologies, especially in the central regions. A total of 22 well resolved significantly bright X-ray peaks (corresponding with high-density regions) are seen in the central parts (within r{sub c} /2) of the clusters. Multiple peaks are seen in central parts of six clusters. We found 11 peaks to have optical counterparts (10 coinciding with the brightest cluster galaxies of the 10 clusters and 1 coinciding with the second brightest galaxy in A539). For most of the clusters, the optical substructures detected in the previous studies are found to be outside the field of view of Chandra. In the spectroscopically produced two-dimensional temperature maps, significantly lower temperatures are seen at the locations of three peaks (two in A539 and one in A376). The centers of five clusters in our sample also host regions of higher temperature compared to the ambient medium, indicating the presence of galaxy scale mergers. The X-ray luminosity, gas mass, and central cooling time estimates for all the clusters are presented. The radial X-ray surface-brightness profiles of all but one of the clusters are found to be best-fitted with a double-β model, pointing toward the presence of double-phased central gas due to cool cores. The cooling time estimates of all the clusters, however, indicate that none of them hosts a strong cool core, although the possibility of weak cool cores cannot be ruled out.

  5. Nonlinear signal-based control with an error feedback action for nonlinear substructuring control

    Science.gov (United States)

    Enokida, Ryuta; Kajiwara, Koichi

    2017-01-01

    A nonlinear signal-based control (NSBC) method utilises the 'nonlinear signal' that is obtained from the outputs of a controlled system and its linear model under the same input signal. Although this method has been examined in numerical simulations of nonlinear systems, its application in physical experiments has not been studied. In this paper, we study an application of NSBC in physical experiments and incorporate an error feedback action into the method to minimise the error and enhance the feasibility in practice. Focusing on NSBC in substructure testing methods, we propose nonlinear substructuring control (NLSC), that is a more general form of linear substructuring control (LSC) developed for dynamical substructured systems. In this study, we experimentally and numerically verified the proposed NLSC via substructuring tests on a rubber bearing used in base-isolated structures. In the examinations, NLSC succeeded in gaining accurate results despite significant nonlinear hysteresis and unknown parameters in the substructures. The nonlinear signal feedback action in NLSC was found to be notably effective in minimising the error caused by nonlinearity or unknown properties in the controlled system. In addition, the error feedback action in NLSC was found to be essential for maintaining stability. A stability analysis based on the Nyquist criterion, which is used particularly for linear systems, was also found to be efficient for predicting the instability conditions of substructuring tests with NLSC and useful for the error feedback controller design.

  6. More pieces of the puzzle: chemistry and substructures in the galactic thick disk

    Energy Technology Data Exchange (ETDEWEB)

    Helmi, Amina [Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9700 AV Groningen (Netherlands); Williams, Mary [Astrophysikalisches Institut Potsdam, An der Sternwarte 16, D-14482 Germany (Germany); Freeman, K. C. [Research School of Astronomy and Astrophysics The Australian National University, Cotter Road Weston Creek, ACT 2611 (Australia); Bland-Hawthorn, J. [Sydney Institute for Astronomy, School of Physics A28, University of Sydney, NSW 2006 (Australia); De Silva, G., E-mail: ahelmi@astro.rug.nl, E-mail: mary@aip.de [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia)

    2014-08-20

    We present a study of the chemical abundances of solar neighborhood stars associated with dynamical structures in the Milky Way's (thick) disk. These stars were identified as an overdensity in the eccentricity range 0.3 < ε < 0.5 in the Copenhagen-Geneva Survey by Helmi et al. We find that stars with these dynamical characteristics do not constitute a homogeneous population. A relatively sharp transition in dynamical and chemical properties appears to occur at a metallicity of [Fe/H] ∼ –0.4. Stars with [Fe/H] > –0.4 have mostly lower eccentricities, smaller vertical velocity dispersions, are α-enhanced, and define a rather narrow sequence in [α/Fe] versus [Fe/H], clearly distinct from that of the thin disk. Stars with [Fe/H] < –0.4 have a range of eccentricities, are hotter vertically, and depict a larger spread in [α/Fe]. We also found tentative evidence of a substructure possibly associated with the disruption of a metal-rich star cluster. The differences between these populations of stars is also present in, e.g., [Zn/Fe], [Ni/Fe], and [SmII/Fe], suggesting a real physical distinction.

  7. The Study of Substructures of Addiction Phenomena in High School Students Using Problem Finding Workshops

    Science.gov (United States)

    Shamsi Meymandi, Manzumeh; Safizadeh, Hossein; Divsalar, Kouros; Rastegariyanzadeh, Ramin; Heravi, Gioia; Mahmoodi, Majid; Kheradmand, Ali

    2011-01-01

    Background Addiction is one of the complicated problems in Iranian young population. The social and cultural dimensions of this social disease are less considered. So considering socio-cultural and environmental resources, this study investigated the substructures of addiction according to the viewpoints of high-school students of Kerman, Iran in 2007-2008. Methods This qualitative study accomplished in ten high schools through a one-day problem finding workshop and continued until data saturation. The resulted terms and phrases were analyzed by content analysis. To assure about the validity and reliability, the outputs reviewed by workshops participants, and classification and codification of the data were executed separately by two experts. Findings A total of 212 students, 45.3% girls and 54.7% boys, participated in the study. The students introduced the followings as the addiction substantial fundaments: lack of knowledge, positive attitude and interpretation of addiction as a value, family or friends' habit, economy status, psycho-personality problems and availability. Rules infirmity or non-implementation of the current rules enforcement, geographical status and addiction as a conspiracy were also observed in students’ statements. Conclusion The positive attitudes and historical roots of addiction along with the process of changing the values caused the growth of drug addiction in young population which could neutralize the security measures, legislations policy and even the knowledge. Therefore, intensification of personal protective factors and culturalization addressed for improving inner layers of values are recommended. PMID:24494110

  8. On quantum algorithms for noncommutative hidden subgroups

    Energy Technology Data Exchange (ETDEWEB)

    Ettinger, M. [Los Alamos National Lab., NM (United States); Hoeyer, P. [Odense Univ. (Denmark)

    1998-12-01

    Quantum algorithms for factoring and discrete logarithm have previously been generalized to finding hidden subgroups of finite Abelian groups. This paper explores the possibility of extending this general viewpoint to finding hidden subgroups of noncommutative groups. The authors present a quantum algorithm for the special case of dihedral groups which determines the hidden subgroup in a linear number of calls to the input function. They also explore the difficulties of developing an algorithm to process the data to explicitly calculate a generating set for the subgroup. A general framework for the noncommutative hidden subgroup problem is discussed and they indicate future research directions.

  9. Jet Substructure: Boosting the Search for New Physics at the LHC

    Science.gov (United States)

    Thaler, Jesse

    2016-03-01

    Collisions at the Large Hadron Collider (LHC) are dominated by jets, collimated sprays of particles that are proxies for underlying quarks and gluons. With the remarkable performance of the ATLAS and CMS detectors, jets can now be characterized not just by their overall direction and energy but also by their substructure. In this talk, I highlight the ways that jet substructure has enhanced the search for new physics at the LHC, including recent excitement over a possible diboson excess. I also explain how theoretical studies of jet substructure have taught us surprising lessons about the nature of the strong force.

  10. Jet Substructure at the Tevatron and LHC: New results, new tools, new benchmarks

    CERN Document Server

    Altheimer, A; Asquith, L; Brooijmans, G; Butterworth, J; Campanelli, M; Chapleau, B; Cholakian, A E; Chou, J P; Dasgupta, M; Davison, A; Dolen, J; Ellis, S D; Essig, R; Fan, J J; Field, R; Fregoso, A; Gallicchio, J; Gershtein, Y; Gomes, A; Haas, A; Halkiadakis, E; Halyo, V; Hoeche, S; Hook, A; Hornig, A; Huang, P; Izaguirre, E; Jankowiak, M; Kribs, G; Krohn, D; Larkoski, A J; Lath, A; Lee, C; Lee, S J; Loch, P; Maksimovic, P; Martinez, M; Miller, D W; Plehn, T; Prokofiev, K; Rahmat, R; Rappoccio, S; Safonov, A; Salam, G P; Schumann, S; Schwartz, M D; Schwartzman, A; Seymour, M; Shao, J; Sinervo, P; Son, M; Soper, D E; Spannowsky, M; Stewart, I W; Strassler, M; Strauss, E; Takeuchi, M; Thaler, J; Thomas, S; Tweedie, B; Vasquez Sierra, R; Vermilion, C K; Villaplana, M; Vos, M; Wacker, J; Walker, D; Walsh, J R; Wang, L-T; Wilbur, S; Yavin, I; Zhu, W

    2012-01-01

    In this report we review recent theoretical progress and the latest experimental results in jet substructure from the Tevatron and the LHC. We review the status of and outlook for calculation and simulation tools for studying jet substructure. Following up on the report of the Boost 2010 workshop, we present a new set of benchmark comparisons of substructure techniques, focusing on the set of variables and grooming methods that are collectively known as "top taggers". To facilitate further exploration, we have attempted to collect, harmonise, and publish software implementations of these techniques.

  11. Exploring Milkyway Halo Substructures with Large-Area Sky Surveys

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ting [Texas A & M Univ., College Station, TX (United States)

    2016-01-01

    Over the last two decades, our understanding of the Milky Way has been improved thanks to large data sets arising from large-area digital sky surveys. The stellar halo is now known to be inhabited by a variety of spatial and kinematic stellar substructures, including stellar streams and stellar clouds, all of which are predicted by hierarchical Lambda Cold Dark Matter models of galaxy formation. In this dissertation, we first present the analysis of spectroscopic observations of individual stars from the two candidate structures discovered using an M-giant catalog from the Two Micron All-Sky Survey. The follow-up observations show that one of the candidates is a genuine structure which might be associated with the Galactic Anticenter Stellar Structure, while the other one is a false detection due to the systematic photometric errors in the survey or dust extinction in low Galactic latitudes. We then presented the discovery of an excess of main sequence turn-off stars in the direction of the constellations of Eridanus and Phoenix from the first-year data of the Dark Energy Survey (DES) – a five-year, 5,000 deg2 optical imaging survey in the Southern Hemisphere. The Eridanus-Phoenix (EriPhe) overdensity is centered around l ~ 285° and b ~ -60° and the Poisson significance of the detection is at least 9σ. The EriPhe overdensity has a cloud-like morphology and the extent is at least ~ 4 kpc by ~ 3 kpc in projection, with a heliocentric distance of about d ~ 16 kpc. The EriPhe overdensity is morphologically similar to the previously-discovered Virgo overdensity and Hercules-Aquila cloud. These three overdensities lie along a polar plane separated by ~ 120° and may share a common origin. In addition to the scientific discoveries, we also present the work to improve the photometric calibration in DES using auxiliary calibration systems, since the photometric errors can cause false detection in first the halo substructure. We present a detailed description of the two

  12. Sub-structures formed in the excited state are responsible for tryptophan residues fluorescence in β-lactoglobulin.

    Science.gov (United States)

    Albani, Jihad-Rene

    2011-07-01

    Origin of tryptophan residues fluorescence in β-lactoglobulin is analyzed. Fluorescence lifetimes and spectra of β-lactoglobulin solution are measured at pH going from 2 to 12 and in 6 M guanidine. Tryptophan residues emit with three lifetimes at all conditions. Two lifetimes (0.4-0.5 ns and 2-4 ns) are in the same range of those measured for tryptophan free in solution. Lifetimes in the denatured states are lower than those measured in the native state. Pre-exponential values are modified with the protein structure. Data are identical to those already obtained for other proteins. Fluorescence lifetimes characterize internal states of the tryptophan residues (Tryptophan sub-structures) independently of the tryptophan environments, the third lifetime results from the interaction that is occurring between the Trp residues and its environment. Pre-exponential values characterize substructures populations. In conclusion, tryptophan mission occurs from substates generated in the excited state. This is in good agreement with the theory we described in recent works.

  13. The Bolocam Galactic Plane Survey. XI. Temperatures and Substructure of Galactic Clumps Based on 350 micron Observations

    CERN Document Server

    Merello, Manuel; Shirley, Yancy L; Rosolowsky, Erik; Ginsburg, Adam; Bally, John; Battersby, Cara; Dunham, Michael M

    2015-01-01

    We present 107 maps of continuum emission at 350 microns from Galactic molecular clumps. Observed sources were mainly selected from the Bolocam Galactic Plane Survey (BGPS) catalog, with 3 additional maps covering star forming regions in the outer Galaxy. The higher resolution of the SHARC-II images (8.5'' beam) compared with the 1.1 mm images from BGPS (33'' beam) allowed us to identify a large population of smaller substructures within the clumps. A catalog is presented for the 1386 sources extracted from the 350 micron maps. The color temperature distribution of clumps based on the two wavelengths has a median of 13.3 K and mean of 16.3 +- 0.4 K, assuming an opacity law index of 1.7. For the structures with the best determined color temperatures, the mean ratio of gas temperature, determined from NH3 observations, to dust color temperature is 0.88 and the median ratio is 0.76. About half the clumps have more than two substructures and 22 clumps have more than 10. The fraction of the mass in dense substruct...

  14. Pseudoscalar searches with dileptonic tops and jet substructure

    Science.gov (United States)

    Gonçalves, Dorival; López-Val, David

    2016-11-01

    The quest for new heavy states is a critical component of the LHC physics program. In this paper, we study the search for pseudoscalar bosons produced in association with a t t ¯ pair. We consider the final state t t ¯A →t t ¯b b ¯ with a dileptonic top-pair signature, and reconstruct the boosted A →b b ¯ candidate with jet substructure techniques, achieving a remarkable sensitivity over a broad range of pseudoscalar masses and Yukawa couplings. We apply this strategy to a type-I two-Higgs-doublet model (2HDM), demonstrating its ability to probe a realistic, UV-complete extended Higgs sector. In particular, we find that the 13 TeV LHC with 300 fb-1 of data can constrain the region tan β >1.5 at 95% C.L. for a light pseudoscalar with mA=50 GeV . Moreover, the whole mass range 20 GeV

  15. Jet substructure and probes of CP violation in Vh production

    CERN Document Server

    Godbole, Rohini M; Mohan, Kirtimaan A; White, Christopher D

    2014-01-01

    We analyse the hVV (V = W, Z) vertex in a model independent way using Vh production. To that end , we consider possible corrections to the Standard Model Higgs Lagrangian, in the form of higher dimensional operators which parametrise the effects of new physics. In our analysis, we pay special attention to linear observables that can be used to probe CP violation in the same. By considering the associated production of a Higgs boson with a vector boson (W or Z), we use jet substructure methods to define angular observables which are sensitive to new physics effects, including an asymmetry which is linearly sensitive to the presence of CP odd effects. We demonstrate how to use these observables to place bounds on the presence of higher dimensional operators, and quantify these statements using a log likelihood analysis. Our approach allows one to probe separately the hZZ and hWW vertices, involving arbitrary combinations of BSM operators, at the Large Hadron Collider.

  16. Jet substructure using semi-inclusive jet functions within SCET

    CERN Document Server

    Kang, Zhong-Bo; Vitev, Ivan

    2016-01-01

    We propose a new method to evaluate jet substructure observables in inclusive jet measurements based upon semi-inclusive jet functions within the framework of Soft Collinear Effective Theory (SCET). In this work we consider the jet fragmentation function, where a hadron $h$ is identified inside a fully reconstructed jet as a first example. We introduce a new semi-inclusive fragmenting jet function ${\\mathcal G}^h_i(z= \\omega_J/\\omega,z_h=\\omega_h/\\omega_J,\\omega_J, R,\\mu)$ which depends on the jet radius $R$ and the large light-cone momenta of the parton '$i$' initiating the jet ($\\omega$), the jet ($\\omega_J$), and the hadron $h$ ($\\omega_h$). We are then able to express the jet fragmentation function as a semi-inclusive jet observable rather than as an exclusive one, which is closer to the actual experimental measurements. We demonstrate the consistency of the effective field theory treatment and standard perturbative QCD calculations at next-to-leading order (NLO). We further derive the renormalization gro...

  17. Shaken and Stirred: The Milky Way's Dark Substructures

    CERN Document Server

    Sawala, Till; Johansson, Peter H; Frenk, Carlos S; Navarro, Julio F; Oman, Kyle A; White, Simon D M

    2016-01-01

    The predicted abundance and properties of the low-mass substructures embedded inside larger dark matter haloes differ sharply among alternative dark matter models. Too small to host galaxies themselves, these subhaloes may still be detected via gravitational lensing, or via perturbations of the Milky Way's globular cluster streams and its stellar disk. Here we use the Apostle cosmological simulations to predict the abundance and the spatial and velocity distributions of subhaloes in the range 10^6.5-10^8.5 solar masses inside haloes of mass ~ 10^12 solar masses in LCDM. Although these subhaloes are themselves devoid of baryons, we find that baryonic effects are important. Compared to corresponding dark matter only simulations, the loss of baryons from subhaloes and stronger tidal disruption due to the presence of baryons near the centre of the main halo, reduce the number of subhaloes by ~ 1/4 to 1/2, independently of subhalo mass, but increasingly towards the host halo centre. We also find that subhaloes hav...

  18. Probing the substructure of $f_0(1370)$

    CERN Document Server

    Fariborz, Amir H; Asrar, Abdorreza

    2015-01-01

    Within an effective nonlinear chiral Lagrangian framework the substructure of $f_0(1370)$ is studied. The investigation is conducted in the context of a global picture of scalar mesons in which the importance of the underlying connections among scalar mesons below and above 1 GeV is recognized and implemented. These connections are due to the mixings among various quark-antiquarks, four-quarks and glue components and play a central role in understanding the properties of scalar mesons. Iterative Monte Carlo simulations are first performed on the 14-dimensional parameter space of the model and sets of points in this parameter space (the global sets) that give an overall agreement with all experimental data on mass spectrum, various decay widths and decay ratios of all isosinglet scalar states below 2 GeV are determined. Then within each global set, subsets that give closest agreement for the properties of $f_0(1370)$ are studied. Unlike the properties of other isosinglet states that show a range of variation w...

  19. Substructural influence in the hot rolling of Al alloys

    Science.gov (United States)

    McQueen, H. J.

    1998-06-01

    The industrial rolling of aluminum alloys is generally conducted in multistage schedules of 10-15 passes partly on reversing mills and partly on continuous mills with temperature declining from 500°C to between 300°C and 250°C. Static recrystallization may take place in long intervals after passes with higher temperature and strain. During lower temperature intervals, only static recovery takes place so that in the following passes the flow curves exhibit higher initial stresses. Dynamic recovery decreases gradually through the hot-, warm-, and cold-working ranges but is reduced as the concentration of solutes and particles increase. Recrystallization is much more sensitive to temperature and alloying and is retarded by increased dynamic recovery. The texture of sheet depends on lattice-dependent Taylor rotations during dislocation slip, enhanced recovery of certain deformation band orientations, and preferred nucleation and growth during interpass pauses or annealing. Schedule optimization can be guided by physical simulation or modeling based on recrystallization kinetics to attain selected strengthening substructure, recrystallized grain size, and texture for product earing control.

  20. Virtual sensing of structural vibrations using dynamic substructuring

    Science.gov (United States)

    Kullaa, Jyrki

    2016-10-01

    Virtual sensing techniques use information available from a limited set of physical sensors together with the finite element model to calculate an estimate of the quantity of interest. In structural dynamics applications, analytical mode shapes from the finite element model are typically used as a basis to estimate the response at unmeasured locations by an expansion algorithm. An alternative is to model only the interesting part of the structure using substructuring techniques, in which the natural modes are replaced by component modes consisting of a selected number of fixed interface modes plus the interface constraint modes. They are mutually independent and compose a valid subspace for estimating the unmeasured response. If the number of interface degrees of freedom is large, interface reduction is applied. The main advantage of the proposed approach is that the modelling effort can be substantially decreased, because only part of the structure is modelled and the modelling uncertainties, non-linearities, or changes in the omitted structure can be ignored. The method is validated by numerical simulations of three different structures under unknown excitation. Different types and locations of virtual sensors are studied. Also, the effects of noise and model errors are investigated. The most accurate estimation is obtained if the virtual sensor is located away from the interface and close to a physical sensor.

  1. Hidden Variable Theories and Quantum Nonlocality

    Science.gov (United States)

    Boozer, A. D.

    2009-01-01

    We clarify the meaning of Bell's theorem and its implications for the construction of hidden variable theories by considering an example system consisting of two entangled spin-1/2 particles. Using this example, we present a simplified version of Bell's theorem and describe several hidden variable theories that agree with the predictions of…

  2. Estimating an Activity Driven Hidden Markov Model

    OpenAIRE

    Meyer, David A.; Shakeel, Asif

    2015-01-01

    We define a Hidden Markov Model (HMM) in which each hidden state has time-dependent $\\textit{activity levels}$ that drive transitions and emissions, and show how to estimate its parameters. Our construction is motivated by the problem of inferring human mobility on sub-daily time scales from, for example, mobile phone records.

  3. Insight: Exploring Hidden Roles in Collaborative Play

    Directory of Open Access Journals (Sweden)

    Tricia Shi

    2015-06-01

    Full Text Available This paper looks into interaction modes between players in co-located, collaborative games. In particular, hidden traitor games, in which one or more players is secretly working against the group mission, has the effect of increasing paranoia and distrust between players, so this paper looks into the opposite of a hidden traitor – a hidden benefactor. Rather than sabotaging the group mission, the hidden benefactor would help the group achieve the end goal while still having a reason to stay hidden. The paper explores what games with such a role can look like and how the role changes player interactions. Finally, the paper addresses the divide between video game and board game interaction modes; hidden roles are not common within video games, but they are of growing prevalence in board games. This fact, combined with the exploration of hidden benefactors, reveals that hidden roles is a mechanic that video games should develop into in order to match board games’ complexity of player interaction modes.

  4. Engineering of Algorithms for Hidden Markov models and Tree Distances

    DEFF Research Database (Denmark)

    Sand, Andreas

    grown exponentially because of drastic improvements in the technology behind DNA and RNA sequencing, and focus on the research field has increased due to its potential to expand our knowledge about biological mechanisms and to improve public health. There has therefore been a continuously growing demand...... of the algorithms to exploit the parallel architecture of modern computers. In this PhD dissertation, I present my work with algorithmic optimizations and parallelizations in primarily two areas in algorithmic bioinformatics: algorithms for analyzing hidden Markov models and algorithms for computing distance...... measures between phylogenetic trees. Hidden Markov models is a class of probabilistic models that is used in a number of core applications in bioinformatics such as modeling of proteins, gene finding and reconstruction of species and population histories. I show how a relatively simple parallelization can...

  5. Sub-structures in the inner halo of the Milky Way

    Directory of Open Access Journals (Sweden)

    Duffau S.

    2012-02-01

    Full Text Available We present a spectroscopic study of a sample of 238 RR Lyrae stars, from the QUEST survey, located in the Galactic halo at distances between 4 and 20 kpc from the Sun. Combining their spatial position and kinematics we were able to identify sub-structures in this part of the halo. Some of those sub-structures may be associated with known halo features like the Virgo Overdensity, the Hercules-Aquila Cloud, and the Anticenter Stream.

  6. Contribution to Structural Elucidation: Behaviours of Substructures Partially Defined from 2D NMR

    Institute of Scientific and Technical Information of China (English)

    EPOUHE, Celine; FAN, Bo-Tao; YUAN, Shen-Gang; PANAYE, A.; DOUCET, J. P

    2003-01-01

    Structural elucidation (automatic determination of the structure of a molecule from its spectra) is frequently hampered by combinatorial explosion when trying to assemble the identified substructures. We devised a new method which can avoid this pitfall by a systematic examination of allowed 13C chemical shifts ranges for all substructures chemically possible and combined with a progressive pruning thanks to neighbouring relationships appearing from 2D NMR. This method is explained by a detailed example.

  7. A NEW METHOD TO QUANTIFY X-RAY SUBSTRUCTURES IN CLUSTERS OF GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Andrade-Santos, Felipe; Lima Neto, Gastao B.; Lagana, Tatiana F. [Departamento de Astronomia, Instituto de Astronomia, Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo, Geofisica e Ciencias Atmosfericas, Rua do Matao 1226, Cidade Universitaria, 05508-090 Sao Paulo, SP (Brazil)

    2012-02-20

    We present a new method to quantify substructures in clusters of galaxies, based on the analysis of the intensity of structures. This analysis is done in a residual image that is the result of the subtraction of a surface brightness model, obtained by fitting a two-dimensional analytical model ({beta}-model or Sersic profile) with elliptical symmetry, from the X-ray image. Our method is applied to 34 clusters observed by the Chandra Space Telescope that are in the redshift range z in [0.02, 0.2] and have a signal-to-noise ratio (S/N) greater than 100. We present the calibration of the method and the relations between the substructure level with physical quantities, such as the mass, X-ray luminosity, temperature, and cluster redshift. We use our method to separate the clusters in two sub-samples of high- and low-substructure levels. We conclude, using Monte Carlo simulations, that the method recuperates very well the true amount of substructure for small angular core radii clusters (with respect to the whole image size) and good S/N observations. We find no evidence of correlation between the substructure level and physical properties of the clusters such as gas temperature, X-ray luminosity, and redshift; however, analysis suggest a trend between the substructure level and cluster mass. The scaling relations for the two sub-samples (high- and low-substructure level clusters) are different (they present an offset, i.e., given a fixed mass or temperature, low-substructure clusters tend to be more X-ray luminous), which is an important result for cosmological tests using the mass-luminosity relation to obtain the cluster mass function, since they rely on the assumption that clusters do not present different scaling relations according to their dynamical state.

  8. Helioscope bounds on hidden sector photons

    Energy Technology Data Exchange (ETDEWEB)

    Redondo, J.

    2007-12-15

    The flux of hypothetical ''hidden photons'' from the Sun is computed under the assumption that they interact with normal matter only through kinetic mixing with the ordinary standard model photon. Requiring that the exotic luminosity is smaller than the standard photon luminosity provides limits for the mixing parameter down to {chi} hidden photon mass. Furthermore, it is pointed point out that helioscopes looking for solar axions are also sensitive to hidden photons. The recent results of the CAST collaboration are used to further constrain the mixing parameter {chi} at low masses (m{sub {gamma}}{sub '}<1 eV) where the luminosity bound is weaker. In this regime the solar hidden photon ux has a sizable contribution of longitudinally polarized hidden photons of low energy which are invisible for current helioscopes. (orig.)

  9. Heating up the Galaxy with hidden photons

    Energy Technology Data Exchange (ETDEWEB)

    Dubovsky, Sergei [Center for Cosmology and Particle Physics, Department of Physics, New York University,New York, NY, 10003 (United States); Hernández-Chifflet, Guzmán [Center for Cosmology and Particle Physics, Department of Physics, New York University,New York, NY, 10003 (United States); Instituto de Física, Facultad de Ingeniería, Universidad de la República,Montevideo, 11300 (Uruguay)

    2015-12-29

    We elaborate on the dynamics of ionized interstellar medium in the presence of hidden photon dark matter. Our main focus is the ultra-light regime, where the hidden photon mass is smaller than the plasma frequency in the Milky Way. We point out that as a result of the Galactic plasma shielding direct detection of ultra-light photons in this mass range is especially challenging. However, we demonstrate that ultra-light hidden photon dark matter provides a powerful heating source for the ionized interstellar medium. This results in a strong bound on the kinetic mixing between hidden and regular photons all the way down to the hidden photon masses of order 10{sup −20} eV.

  10. Helioscope bounds on hidden sector photons

    Energy Technology Data Exchange (ETDEWEB)

    Redondo, J.

    2007-12-15

    The flux of hypothetical ''hidden photons'' from the Sun is computed under the assumption that they interact with normal matter only through kinetic mixing with the ordinary standard model photon. Requiring that the exotic luminosity is smaller than the standard photon luminosity provides limits for the mixing parameter down to {chi} hidden photon mass. Furthermore, it is pointed point out that helioscopes looking for solar axions are also sensitive to hidden photons. The recent results of the CAST collaboration are used to further constrain the mixing parameter {chi} at low masses (m{sub {gamma}}{sub '}<1 eV) where the luminosity bound is weaker. In this regime the solar hidden photon ux has a sizable contribution of longitudinally polarized hidden photons of low energy which are invisible for current helioscopes. (orig.)

  11. Hidden Web信息获取

    Institute of Scientific and Technical Information of China (English)

    陈珂; 陈小英; 徐科

    2007-01-01

    如今Web上越来越多的信息可以通过查询接口获得,但为了获取某Hidden Web站点的页面,用户不得不键入一系列的关键词.由于没有直接指向Hidden Web页面的静态链接,当前大多搜索引擎不能发现和索引这些页面.然而,研究表明,由Hidden Web站点提供的高质量的信息对许多用户来说非常有价值.文章通过研究针对特定类型的表单,建立一个有效的Hidden Web爬虫,以便获取Hidden Web后台数据库信息.

  12. Systematic benchmark of substructure search in molecular graphs - From Ullmann to VF2

    Directory of Open Access Journals (Sweden)

    Ehrlich Hans-Christian

    2012-07-01

    Full Text Available Abstract Background Searching for substructures in molecules belongs to the most elementary tasks in cheminformatics and is nowadays part of virtually every cheminformatics software. The underlying algorithms, used over several decades, are designed for the application to general graphs. Applied on molecular graphs, little effort has been spend on characterizing their performance. Therefore, it is not clear how current substructure search algorithms behave on such special graphs. One of the main reasons why such an evaluation was not performed in the past was the absence of appropriate data sets. Results In this paper, we present a systematic evaluation of Ullmann’s and the VF2 subgraph isomorphism algorithms on molecular data. The benchmark set consists of a collection of 1235 SMARTS substructure expressions and selected molecules from the ZINC database. The benchmark evaluates substructures search times for complete database scans as well as individual substructure-molecule pairs. In detail, we focus on the influence of substructure formulation and size, the impact of molecule size, and the ability of both algorithms to be used on multiple cores. Conclusions The results show a clear superiority of the VF2 algorithm in all test scenarios. In general, both algorithms solve most instances in less than one millisecond, which we consider to be acceptable. Still, in direct comparison, the VF2 is most often several folds faster than Ullmann’s algorithm. Additionally, Ullmann’s algorithm shows a surprising number of run time outliers.

  13. Measuring the power spectrum of dark matter substructure using strong gravitational lensing

    Science.gov (United States)

    Hezaveh, Yashar; Dalal, Neal; Holder, Gilbert; Kisner, Theodore; Kuhlen, Michael; Perreault Levasseur, Laurence

    2016-11-01

    In recent years, it has become possible to detect individual dark matter subhalos near images of strongly lensed extended background galaxies. Typically, only the most massive subhalos in the strong lensing region may be detected this way. In this work, we show that strong lenses may also be used to constrain the much more numerous population of lower mass subhalos that are too small to be detected individually. In particular, we show that the power spectrum of projected density fluctuations in galaxy halos can be measured using strong gravitational lensing. We develop the mathematical framework of power spectrum estimation, and test our method on mock observations. We use our results to determine the types of observations required to measure the substructure power spectrum with high significance. We predict that deep observations (~10 hours on a single target) with current facilities can measure this power spectrum at the 3σ level, with no apparent degeneracy with unknown clumpiness in the background source structure or fluctuations from detector noise. Upcoming ALMA measurements of strong lenses are capable of placing strong constraints on the abundance of dark matter subhalos and the underlying particle nature of dark matter.

  14. The Next Generation Virgo Cluster Survey. XIX. Tomography of Milky Way Substructures in the NGVS Footprint

    CERN Document Server

    Lokhorst, Deborah; McConnachie, Alan; Navarro, Julio F; Ferrarese, Laura; Côté, Patrick; Liu, Chengze; Peng, Eric W; Gwyn, Stephen D J; Cuillandre, Jean-Charles; Guhathakurta, Puragra

    2016-01-01

    The Next Generation Virgo Cluster Survey (NGVS) is a deep $u^*giz$ survey targeting the Virgo cluster of galaxies at 16.5~Mpc. This survey provides high-quality photometry over an $\\sim$ 100 deg$^2$ region straddling the constellations of Virgo and Coma Berenices. This sightline through the Milky Way is noteworthy in that it intersects two of the most prominent substructures in the Galactic halo: the Virgo Over-Density (VOD) and Sagittarius stellar stream (close to its bifurcation point). In this paper, we use deep $u^*gi$ imaging from the NGVS to perform tomography of the VOD and Sagittarius stream using main-sequence turnoff (MSTO) stars as a halo tracer population. The VOD, whose centroid is known to lie at somewhat lower declinations ($\\alpha \\sim 190^\\circ$, $\\delta \\sim -5^\\circ$) than is covered by the NGVS, is nevertheless clearly detected in the NGVS footprint at distances between $\\sim$ 8 and 25~kpc. By contrast, the Sagittarius stream is found to slice directly across the NGVS field at distances be...

  15. Chemical Abundances of Planetary Nebulae in the Substructures of M31

    CERN Document Server

    Fang, Xuan; Guerrero, Martin A; Liu, Xiaowei; Yuan, Haibo; Zhang, Yong; Zhang, Bing

    2015-01-01

    We present deep spectroscopy of planetary nebulae (PNe) that are associated with the substructures of the Andromeda Galaxy (M31). The spectra were obtained with the OSIRIS spectrograph on the 10.4 m GTC. Seven targets were selected for the observations, three in the Northern Spur and four associated with the Giant Stream. The most distant target in our sample, with a rectified galactocentric distance >100 kpc, was the first PN discovered in the outer streams of M31. The [O III] 4363 auroral line was well detected in the spectra of all targets, enabling electron temperature determination. Ionic abundances are derived based on the [O III] temperatures, and elemental abundances of helium, nitrogen, oxygen, neon, sulfur, and argon are estimated. The relatively low N/O and He/H ratios as well as abundance ratios of alpha-elements indicate that our target PNe might belong to populations as old as ~2 Gyr. Our PN sample, including the current seven and the previous three observed by Fang et al., have rather homogeneo...

  16. Nuclear substructure reorganization during late stageerythropoiesis is selective and does not involve caspase cleavage ofmajor nuclear substructural proteins

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, Sharon Wald; Lo, Annie J.; Short, Sarah A.; Koury, MarkJ.; Mohandas, Narla; Chasis, Joel Anne

    2005-04-06

    Enucleation, a rare feature of mammalian differentiation, occurs in three cell types: erythroblasts, lens epithelium and keratinocytes. Previous investigations suggest that caspase activation functions in lens epithelial and keratinocyte enucleation, as well as in early erythropoiesis encompassing BFU-E differentiation to proerythroblast. To determine whether caspase activation contributes to later erythropoiesis and whether nuclear substructures other than chromatin reorganize, we analyzed distributions of nuclear subcompartment proteins and assayed for caspase-induced cleavage of subcompartmental target proteins in mouse erythroblasts. We found that patterns of lamin B in the filamentous network interacting with both the nuclear envelope and DNA, nuclear matrix protein NuMA, and splicing factors Sm and SC35 persisted during nuclear condensation, consistent with effective transcription of genes expressed late in differentiation. Thus nuclear reorganization prior to enucleation is selective, allowing maintenance of critical transcriptional processes independent of extensive chromosomal reorganization. Consistent with these data, we found no evidence for caspase-induced cleavage of major nuclear subcompartment proteins during late erythropoiesis, in contrast to what has been observed in early erythropoiesis and in lens epithelial and keratinocyte differentiation. These findings imply that nuclear condensation and extrusion during terminal erythroid differentiation involve novel mechanisms that do not entail major activation of apoptotic machinery.

  17. Lensing substructure quantification in RXJ1131-1231: a 2 keV lower bound on dark matter thermal relic mass

    Science.gov (United States)

    Birrer, Simon; Amara, Adam; Refregier, Alexandre

    2017-05-01

    We study the substructure content of the strong gravitational lens RXJ1131-1231 through a forward modelling approach that relies on generating an extensive suite of realistic simulations. We use a semi-analytic merger tree prescription that allows us to stochastically generate substructure populations whose properties depend on the dark matter particle mass. These synthetic halos are then used as lenses to produce realistic mock images that have the same features, e.g. luminous arcs, quasar positions, instrumental noise and PSF, as the data. We then analyse the data and the simulations in the same way with summary statistics that are sensitive to the signal being targeted and are able to constrain models of dark matter statistically using Approximate Bayesian Computing (ABC) techniques. {In this work, we focus on the thermal relic mass estimate and fix the semi-analytic descriptions of the substructure evolution based on recent literature.} We are able, based on the HST data for RXJ1131-1231, to rule out a warm dark matter thermal relic mass below 2 keV at the 2σ confidence level.

  18. Hidden scale invariance of metals

    DEFF Research Database (Denmark)

    Hummel, Felix; Kresse, Georg; Dyre, Jeppe C.

    2015-01-01

    available. Hidden scale invariance is demonstrated in detail for magnesium by showing invariance of structure and dynamics. Computed melting curves of period three metals follow curves with invariance (isomorphs). The experimental structure factor of magnesium is predicted by assuming scale invariant...... of metals making the condensed part of the thermodynamic phase diagram effectively one dimensional with respect to structure and dynamics. DFT computed density scaling exponents, related to the Grüneisen parameter, are in good agreement with experimental values for the 16 elements where reliable data were......Density functional theory (DFT) calculations of 58 liquid elements at their triple point show that most metals exhibit near proportionality between the thermal fluctuations of the virial and the potential energy in the isochoric ensemble. This demonstrates a general “hidden” scale invariance...

  19. Hidden scale in quantum mechanics

    CERN Document Server

    Giri, Pulak Ranjan

    2007-01-01

    We show that the intriguing localization of a free particle wave-packet is possible due to a hidden scale present in the system. Self-adjoint extensions (SAE) is responsible for introducing this scale in quantum mechanical models through the nontrivial boundary conditions. We discuss a couple of classically scale invariant free particle systems to illustrate the issue. In this context it has been shown that a free quantum particle moving on a full line may have localized wave-packet around the origin. As a generalization, it has also been shown that particles moving on a portion of a plane or on a portion of a three dimensional space can have unusual localized wave-packet.

  20. Analysis of substructural variation in families of enzymatic proteins with applications to protein function prediction

    Directory of Open Access Journals (Sweden)

    Fofanov Viacheslav Y

    2010-05-01

    Full Text Available Abstract Background Structural variations caused by a wide range of physico-chemical and biological sources directly influence the function of a protein. For enzymatic proteins, the structure and chemistry of the catalytic binding site residues can be loosely defined as a substructure of the protein. Comparative analysis of drug-receptor substructures across and within species has been used for lead evaluation. Substructure-level similarity between the binding sites of functionally similar proteins has also been used to identify instances of convergent evolution among proteins. In functionally homologous protein families, shared chemistry and geometry at catalytic sites provide a common, local point of comparison among proteins that may differ significantly at the sequence, fold, or domain topology levels. Results This paper describes two key results that can be used separately or in combination for protein function analysis. The Family-wise Analysis of SubStructural Templates (FASST method uses all-against-all substructure comparison to determine Substructural Clusters (SCs. SCs characterize the binding site substructural variation within a protein family. In this paper we focus on examples of automatically determined SCs that can be linked to phylogenetic distance between family members, segregation by conformation, and organization by homology among convergent protein lineages. The Motif Ensemble Statistical Hypothesis (MESH framework constructs a representative motif for each protein cluster among the SCs determined by FASST to build motif ensembles that are shown through a series of function prediction experiments to improve the function prediction power of existing motifs. Conclusions FASST contributes a critical feedback and assessment step to existing binding site substructure identification methods and can be used for the thorough investigation of structure-function relationships. The application of MESH allows for an automated

  1. Common substructure in otoacoustic emission spectra of land vertebrates

    Science.gov (United States)

    Manley, Geoffrey A.; Köppl, Christine; Bergevin, Christopher

    2015-12-01

    In humans, a similar spectral periodicity is found in all otoacoustic emission types and in threshold fine structure. This may reflect travelling wave phase and reflectance from "structural roughness" in the organ of Corti, or entrainment and suppressive interactions between emissions. To further understand these phenomena, we have examined spontaneous otoacoustic emission (SOAE) spectra in 9 lizard species and the barn owl and find a comparable periodicity. Importantly, the frequency spacing between SOAE peaks was independent of the physical spacing and of the frequency space constants in hearing organs. In 9 lizard species, median spectral gaps lay between 219 and 461 Hz, with no correlation to papillar length (0.3 to 2.1 mm). Similarly in much longer organs: In humans (35 mm), SOAE spectral gaps vary up to 220 Hz at 4 kHz; in the barn owl (11 mm), the median SOAE peak spacing was 395Hz. In the barn owl, a very large space constant between 5 and 10 kHz (5 mm/octave) contrasts with stable SOAE spacing between 1 and 11 kHz. Similar SOAE spectral gaps across all species suggests they represent a basic frequency grating revealing local phase-dependent interactions between active hair cells, a feature not determined by macro-structural anatomy. Emission spectral spacing is independent of cochlear length, of the frequency space constant, of the existence of travelling waves or of a tectorial membrane. Our data suggest that there are greater similarities between frequency selectivity reflected at the level of the hair cells' spontaneous mechanical output (OAEs) than there are at the level of the auditory nerve, where macro-structural anatomy links hair-cell activity differentially to the neural output. Apparently, all hair-cell arrays show a similar frequency substructure not directly replicated in neural tuning.

  2. Jet substructure using semi-inclusive jet functions in SCET

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Zhong-Bo [Theoretical Division, Los Alamos National Laboratory,Los Alamos, NM 87545 (United States); Department of Physics and Astronomy, University of California,Los Angeles, CA 90095 (United States); Ringer, Felix; Vitev, Ivan [Theoretical Division, Los Alamos National Laboratory,Los Alamos, NM 87545 (United States)

    2016-11-25

    We propose a new method to evaluate jet substructure observables in inclusive jet measurements, based upon semi-inclusive jet functions in the framework of Soft Collinear Effective Theory (SCET). As a first example, we consider the jet fragmentation function, where a hadron h is identified inside a fully reconstructed jet. We introduce a new semi-inclusive fragmenting jet function G{sub i}{sup h}(z=ω{sub J}/ω,z{sub h}=ω{sub h}/ω{sub J},ω{sub J},R,μ), which depends on the jet radius R and the large light-cone momenta of the parton ‘i’ initiating the jet (ω), the jet (ω{sub J}), and the hadron h (ω{sub h}). The jet fragmentation function can then be expressed as a semi-inclusive observable, in the spirit of actual experimental measurements, rather than as an exclusive one. We demonstrate the consistency of the effective field theory treatment and standard perturbative QCD calculations of this observable at next-to-leading order (NLO). The renormalization group (RG) equation for the semi-inclusive fragmenting jet function G{sub i}{sup h}(z,z{sub h},ω{sub J},R,μ) are also derived and shown to follow exactly the usual timelike DGLAP evolution equations for fragmentation functions. The newly obtained RG equations can be used to perform the resummation of single logarithms of the jet radius parameter R up to next-to-leading logarithmic (NLL{sub R}) accuracy. In combination with the fixed NLO calculation, we obtain NLO+NLL{sub R} results for the hadron distribution inside the jet. We present numerical results for pp→(jet h)X in the new framework, and find excellent agreement with existing LHC experimental data.

  3. Substructure method in high-speed monorail dynamic problems

    Science.gov (United States)

    Ivanchenko, I. I.

    2008-12-01

    combined schemes modeling a strained elastic compound moving structure and a monorail elevated track. The problems of development of methods for dynamic analysis of monorails are very topical, especially because of increasing speeds of the rolling stock motion. These structures are studied in [16-18]. In the present paper, the above problem is solved by using the method for the moving load analysis and a step procedure of integration with respect to time, which were proposed in [9, 19], respectively. Further, these components are used to enlarge the possibilities of the substructure method in problems of dynamics. In the approach proposed for moving load analysis of structures, for a substructure (having the shape of a boundary element or a superelement) we choose an object moving at a constant speed (a monorail rolling stock); in this case, we use rod boundary elements of large length, which are gathered in a system modeling these objects. In particular, sets of such elements form a model of a monorail rolling stock, namely, carriage hulls, wheeled carts, elements of the wheel spring suspension, models of continuous beams of monorail ways and piers with foundations admitting emergency subsidence and unilateral links. These specialized rigid finite elements with linear and nonlinear links, included into the set of earlier proposed finite elements [14, 19], permit studying unsteady vibrations in the "monorail train-elevated track" (MTET) system taking into account various irregularities on the beam-rail, the pier emergency subsidence, and their elastic support by the basement. In this case, a high degree of the structure spatial digitization is obtained by using rods with distributed parameters in the analysis. The displacements are approximated by linear functions and trigonometric Fourier series, which, as was already noted, permits increasing the number of degrees of freedom of the system under study simultaneously preserving the order of the resolving system of

  4. A genome-wide analysis of population structure in the Finnish Saami with implications for genetic association studies.

    Science.gov (United States)

    Huyghe, Jeroen R; Fransen, Erik; Hannula, Samuli; Van Laer, Lut; Van Eyken, Els; Mäki-Torkko, Elina; Aikio, Pekka; Sorri, Martti; Huentelman, Matthew J; Van Camp, Guy

    2011-03-01

    The understanding of patterns of genetic variation within and among human populations is a prerequisite for successful genetic association mapping studies of complex diseases and traits. Some populations are more favorable for association mapping studies than others. The Saami from northern Scandinavia and the Kola Peninsula represent a population isolate that, among European populations, has been less extensively sampled, despite some early interest for association mapping studies. In this paper, we report the results of a first genome-wide SNP-based study of genetic population structure in the Finnish Saami. Using data from the HapMap and the human genome diversity project (HGDP-CEPH) and recently developed statistical methods, we studied individual genetic ancestry. We quantified genetic differentiation between the Saami population and the HGDP-CEPH populations by calculating pair-wise F(ST) statistics and by characterizing identity-by-state sharing for pair-wise population comparisons. This study affirms an east Asian contribution to the predominantly European-derived Saami gene pool. Using model-based individual ancestry analysis, the median estimated percentage of the genome with east Asian ancestry was 6% (first and third quartiles: 5 and 8%, respectively). We found that genetic similarity between population pairs roughly correlated with geographic distance. Among the European HGDP-CEPH populations, F(ST) was smallest for the comparison with the Russians (F(ST)=0.0098), and estimates for the other population comparisons ranged from 0.0129 to 0.0263. Our analysis also revealed fine-scale substructure within the Finnish Saami and warns against the confounding effects of both hidden population structure and undocumented relatedness in genetic association studies of isolated populations.

  5. Hidden torsion, 3-manifolds, and homology cobordism

    CERN Document Server

    Cha, Jae Choon

    2011-01-01

    This paper continues our exploration of homology cobordism of 3-manifolds using our recent results on Cheeger-Gromov rho-invariants associated to amenable representations. We introduce a new type of torsion in 3-manifold groups we call hidden torsion, and an algebraic approximation we call local hidden torsion. We construct infinitely many hyperbolic 3-manifolds which have local hidden torsion in the transfinite lower central subgroup. By realizing Cheeger-Gromov invariants over amenable groups, we show that our hyperbolic 3-manifolds are not pairwise homology cobordant, yet remain indistinguishable by any prior known homology cobordism invariants.

  6. A survey of hidden-variables theories

    CERN Document Server

    Belinfante, F J

    1973-01-01

    A Survey of Hidden-Variables Theories is a three-part book on the hidden-variable theories, referred in this book as """"theories of the first kind"""". Part I reviews the motives in developing different types of hidden-variables theories. The quest for determinism led to theories of the first kind; the quest for theories that look like causal theories when applied to spatially separated systems that interacted in the past led to theories of the second kind. Parts II and III further describe the theories of the first kind and second kind, respectively. This book is written to make the literat

  7. Visible Effects of Invisible Hidden Valley Radiation

    CERN Document Server

    Carloni, Lisa

    2010-01-01

    Assuming there is a new gauge group in a Hidden Valley, and a new type of radiation, can we observe it through its effect on the kinematic distributions of recoiling visible particles? Specifically, what are the collider signatures of radiation in a hidden sector? We address these questions using a generic SU(N)-like Hidden Valley model that we implement in Pythia. We find that in both the e+e- and the LHC cases the kinematic distributions of the visible particles can be significantly affected by the valley radiation. Without a proper understanding of such effects, inferred masses of "communicators" and of invisible particles can be substantially off.

  8. The Extended Halo of Centaurus A: Uncovering Satellites, Streams, and Substructures

    Science.gov (United States)

    Crnojević, D.; Sand, D. J.; Spekkens, K.; Caldwell, N.; Guhathakurta, P.; McLeod, B.; Seth, A.; Simon, J. D.; Strader, J.; Toloba, E.

    2016-05-01

    We present the widest-field resolved stellar map to date of the closest (D˜ 3.8 Mpc) massive elliptical galaxy NGC 5128 (Centaurus A; Cen A), extending out to a projected galactocentric radius of ˜150 kpc. The data set is part of our ongoing Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS) utilizing the Magellan/Megacam imager. We resolve a population of old red giant branch (RGB) stars down to ˜1.5 mag below the tip of the RGB, reaching surface brightness limits as low as {μ }V,0˜ 32 mag arcsec-2. The resulting spatial stellar density map highlights a plethora of previously unknown streams, shells, and satellites, including the first tidally disrupting dwarf around Cen A (CenA-MM-Dw3), which underline its active accretion history. We report 13 previously unknown dwarf satellite candidates, of which 9 are confirmed to be at the distance of Cen A (the remaining 4 are not resolved into stars), with magnitudes in the range {M}V=-7.2 to -13.0, central surface brightness values of {μ }V,0=25.4{--}26.9 mag arcsec-2, and half-light radii of {r}h=0.22{--}2.92 {{kpc}}. These values are in line with Local Group dwarfs but also lie at the faint/diffuse end of their distribution; interestingly, CenA-MM-Dw3 has similar properties to the recently discovered ultradiffuse galaxies in Virgo and Coma. Most of the new dwarfs are fainter than the previously known Cen A satellites. The newly discovered dwarfs and halo substructures are discussed in light of their stellar populations, and they are compared to those discovered by the PAndAS survey of M31. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

  9. Hidden systematics of fission channels

    Directory of Open Access Journals (Sweden)

    Schmidt Karl-Heinz

    2013-12-01

    of the fissioning system obey a hidden systematics that can be explained by the number of states in the vicinity of the outer fission barrier as a function of mass asymmetry, if the potential is constructed as the sum of the macroscopic contribution of the compound nucleus and empirically determined fragment shells. This hidden systematics also explains the transition from asymmetric to symmetric fission around 226Th and around 258Fm.

  10. Coding with partially hidden Markov models

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Rissanen, J.

    1995-01-01

    Partially hidden Markov models (PHMM) are introduced. They are a variation of the hidden Markov models (HMM) combining the power of explicit conditioning on past observations and the power of using hidden states. (P)HMM may be combined with arithmetic coding for lossless data compression. A general...... 2-part coding scheme for given model order but unknown parameters based on PHMM is presented. A forward-backward reestimation of parameters with a redefined backward variable is given for these models and used for estimating the unknown parameters. Proof of convergence of this reestimation is given....... The PHMM structure and the conditions of the convergence proof allows for application of the PHMM to image coding. Relations between the PHMM and hidden Markov models (HMM) are treated. Results of coding bi-level images with the PHMM coding scheme is given. The results indicate that the PHMM can adapt...

  11. UV Photography Shows Hidden Sun Damage

    Science.gov (United States)

    ... mcat1=de12", ]; for (var c = 0; c UV photography shows hidden sun damage A UV photograph gives ... developing skin cancer and prematurely aged skin. Normal photography UV photography 18 months of age: This boy's ...

  12. Faddeev-Jackiw approach to hidden symmetries

    CERN Document Server

    Wotzasek, C

    1994-01-01

    The study of hidden symmetries within Dirac's formalism does not possess a systematic procedure due to the lack of first-class constraints to act as symmetry generators. On the other hand, in the Faddeev-Jackiw approach, gauge and reparametrization symmetries are generated by the null eigenvectors of the sympletic matrix and not by constraints, suggesting the possibility of dealing systematically with hidden symmetries through this formalism. It is shown in this paper that indeed hidden symmetries of noninvariant or gauge fixed systems are equally well described by null eigenvectors of the sympletic matrix, just as the explicit invariances. The Faddeev-Jackiw approach therefore provide a systematic algorithm for treating all sorts of symmetries in an unified way. This technique is illustrated here by the SL(2,R) Kac-Moody current algebra of the 2-D induced gravity proposed by Polyakov, which is a hidden symmetry in the canonical approach of constrained systems via Dirac's method, after conformal and reparamet...

  13. Fibroid Tumors in Women: A Hidden Epidemic?

    Science.gov (United States)

    ... Issue Past Issues Fibroid Tumors in Women: A Hidden Epidemic? Past Issues / Spring 2007 Table of Contents ... fibroids@rics.bwh.harvard.edu , or visit our Web site: www.fibroids.net . You may also write ...

  14. Hidden Regular Variation: Detection and Estimation

    CERN Document Server

    Mitra, Abhimanyu

    2010-01-01

    Hidden regular variation defines a subfamily of distributions satisfying multivariate regular variation on $\\mathbb{E} = [0, \\infty]^d \\backslash \\{(0,0, ..., 0) \\} $ and models another regular variation on the sub-cone $\\mathbb{E}^{(2)} = \\mathbb{E} \\backslash \\cup_{i=1}^d \\mathbb{L}_i$, where $\\mathbb{L}_i$ is the $i$-th axis. We extend the concept of hidden regular variation to sub-cones of $\\mathbb{E}^{(2)}$ as well. We suggest a procedure of detecting the presence of hidden regular variation, and if it exists, propose a method of estimating the limit measure exploiting its semi-parametric structure. We exhibit examples where hidden regular variation yields better estimates of probabilities of risk sets.

  15. An algebraic sub-structuring method for large-scale eigenvaluecalculation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, C.; Gao, W.; Bai, Z.; Li, X.; Lee, L.; Husbands, P.; Ng, E.

    2004-05-26

    We examine sub-structuring methods for solving large-scalegeneralized eigenvalue problems from a purely algebraic point of view. Weuse the term "algebraic sub-structuring" to refer to the process ofapplying matrix reordering and partitioning algorithms to divide a largesparse matrix into smaller submatrices from which a subset of spectralcomponents are extracted and combined to provide approximate solutions tothe original problem. We are interested in the question of which spectralcomponentsone should extract from each sub-structure in order to producean approximate solution to the original problem with a desired level ofaccuracy. Error estimate for the approximation to the small esteigen pairis developed. The estimate leads to a simple heuristic for choosingspectral components (modes) from each sub-structure. The effectiveness ofsuch a heuristic is demonstrated with numerical examples. We show thatalgebraic sub-structuring can be effectively used to solve a generalizedeigenvalue problem arising from the simulation of an acceleratorstructure. One interesting characteristic of this application is that thestiffness matrix produced by a hierarchical vector finite elements schemecontains a null space of large dimension. We present an efficient schemeto deflate this null space in the algebraic sub-structuringprocess.

  16. New constraints on the complex mass substructure in Abell 1689 from gravitational flexion

    Science.gov (United States)

    Leonard, Adrienne; King, Lindsay J.; Goldberg, David M.

    2011-05-01

    In a recent publication, the flexion aperture mass statistic was found to provide a robust and effective method by which substructure in galaxy clusters might be mapped. Moreover, we suggested that the masses and mass profile of structures might be constrained using this method. In this paper, we apply the flexion aperture mass technique to HST ACS images of Abell 1689. We demonstrate that the flexion aperture mass statistic is sensitive to small-scale structures in the central region of the cluster. While the central potential is not constrained by our method, due largely to missing data in the central 0.5 arcmin of the cluster, we are able to place constraints on the masses and mass profiles of prominent substructures. We identify four separate mass peaks, and use the peak aperture mass signal and zero signal radius in each case to constrain the masses and mass profiles of these substructures. The three most massive peaks exhibit complex small-scale structure, and the masses indicated by the flexion aperture mass statistic suggest that these three peaks represent the dominant substructure component of the cluster (˜7 × 1014 h-1 M⊙). Their complex structure indicates that the cluster - far from being relaxed - may have recently undergone a merger. The smaller, subsidiary peak is located coincident with a group of galaxies within the cluster, with mass ˜1 × 1014 h-1 M⊙. These results are in excellent agreement with previous substructure studies of this cluster.

  17. Efficient substructure searching of large chemical libraries: the ABCD chemical cartridge.

    Science.gov (United States)

    Agrafiotis, Dimitris K; Lobanov, Victor S; Shemanarev, Maxim; Rassokhin, Dmitrii N; Izrailev, Sergei; Jaeger, Edward P; Alex, Simson; Farnum, Michael

    2011-12-27

    Efficient substructure searching is a key requirement for any chemical information management system. In this paper, we describe the substructure search capabilities of ABCD, an integrated drug discovery informatics platform developed at Johnson & Johnson Pharmaceutical Research & Development, L.L.C. The solution consists of several algorithmic components: 1) a pattern mapping algorithm for solving the subgraph isomorphism problem, 2) an indexing scheme that enables very fast substructure searches on large structure files, 3) the incorporation of that indexing scheme into an Oracle cartridge to enable querying large relational databases through SQL, and 4) a cost estimation scheme that allows the Oracle cost-based optimizer to generate a good execution plan when a substructure search is combined with additional constraints in a single SQL query. The algorithm was tested on a public database comprising nearly 1 million molecules using 4,629 substructure queries, the vast majority of which were submitted by discovery scientists over the last 2.5 years of user acceptance testing of ABCD. 80.7% of these queries were completed in less than a second and 96.8% in less than ten seconds on a single CPU, while on eight processing cores these numbers increased to 93.2% and 99.7%, respectively. The slower queries involved extremely generic patterns that returned the entire database as screening hits and required extensive atom-by-atom verification.

  18. Formulation of an experimental substructure model using a Craig-Bampton based transmission simulator

    Science.gov (United States)

    Kammer, Daniel C.; Allen, Mathew S.; Mayes, Randy L.

    2015-12-01

    Experimental-analytical substructuring is attractive when there is motivation to replace one or more system subcomponents with an experimental model. This experimentally derived substructure can then be coupled to finite element models of the rest of the structure to predict the system response. The transmission simulator method couples a fixture to the component of interest during a vibration test in order to improve the experimental model for the component. The transmission simulator is then subtracted from the tested system to produce the experimental component. The method reduces ill-conditioning by imposing a least squares fit of constraints between substructure modal coordinates to connect substructures, instead of directly connecting physical interface degrees of freedom. This paper presents an alternative means of deriving the experimental substructure model, in which a Craig-Bampton representation of the transmission simulator is created and subtracted from the experimental measurements. The corresponding modal basis of the transmission simulator is described by the fixed-interface modes, rather than free modes that were used in the original approach. These modes do a better job of representing the shape of the transmission simulator as it responds within the experimental system, leading to more accurate results using fewer modes. The new approach is demonstrated using a simple finite element model based example with a redundant interface.

  19. Extreme Brightness Temperatures and Refractive Substructure in 3C273 with RadioAstron

    CERN Document Server

    Johnson, Michael D; Gwinn, Carl R; Gurvits, Leonid I; Narayan, Ramesh; Macquart, Jean-Pierre; Jauncey, David L; Voitsik, Peter A; Anderson, James M; Sokolovsky, Kirill V; Lisakov, Mikhail M

    2016-01-01

    Earth-space interferometry with RadioAstron provides the highest direct angular resolution ever achieved in astronomy at any wavelength. RadioAstron detections of the classic quasar 3C273 on interferometric baselines up to 171,000 km suggest brightness temperatures exceeding expected limits from the "inverse-Compton catastrophe" by two orders of magnitude. We show that at 18 cm, these estimates most probably arise from refractive substructure introduced by scattering in the interstellar medium. We use the scattering properties to estimate an intrinsic brightness temperature of 7*10^12 K, which is consistent with expected theoretical limits, but which is ~15 times lower than estimates that neglect substructure. At 6 cm, the substructure influences the measured values appreciably but gives an estimated brightness temperature that is comparable to models that do not account for the substructure. At 1.3 cm, the substructure does not affect the extremely high inferred brightness temperatures, in excess of 10^13 K....

  20. Hidden figures are ever present.

    Science.gov (United States)

    Mens, L H; Leeuwenberg, E L

    1988-11-01

    Preference judgments about alternative interpretations of unambiguous patterns can be explained in terms of a rivalry between a preferred and a second-best interpretation (cf. Leeuwenberg & Buffart, 1983). We tested whether this second-best interpretation corresponds to a suppressed but concurrently present interpretation or whether it merely reflects an alternative view that happens to be preferred less often. Two patterns were present immediately following each other with a very short onset asynchrony: a complete pattern and one out of three possible subpatterns of it, corresponding to the best, the second best, or an odd interpretation of the complete pattern. Subjects indicated which subpattern was presented by choosing among the three subpatterns shown after each trial. The scores, corrected for response-bias effects, indicated a relative facilitation of the second-best interpretation, in agreement with its predicted "hidden" presence. This result is more in line with theories that capitalize on the quality of the finally selected representation than with processing models aimed at reaching one single solution as fast and as economically as possible.

  1. Hidden Local Symmetry and Beyond

    CERN Document Server

    Yamawaki, Koichi

    2016-01-01

    Gerry Brown was a godfather of our hidden local symmetry (HLS) for the vector meson from the birth of the theory throughout his life. The HLS is originated from very nature of the nonlinear realization of the symmetry G based on the manifold G/H, and thus is universal to any physics based on the nonlinear realization. Here I focus on the Higgs Lagrangian of the Standard Model (SM), which is shown to be equivalent to the nonlinear sigma model based on G/H= SU(2)_L x SU(2)_R/SU(2)_V with additional symmetry, the nonlinearly realized scale symmetry. Then the SM does have a dynamical gauge boson of the SU(2)_V HLS, "SM rho meson", in addition to the Higgs as a pseudo dilaton as well as the NG bosons to be absorbed into the W and Z. Based on the recent work done with S. Matsuzaki and H. Ohki, I discuss a novel possibility that the SM rho meson acquires kinetic term by the SM dynamics itself, which then stabilizes the skyrmion dormant in the SM as a viable candidate for the dark matter, what we call "Dark SM skyrmi...

  2. Hidden local symmetry and beyond

    Science.gov (United States)

    Yamawaki, Koichi

    Gerry Brown was a godfather of our hidden local symmetry (HLS) for the vector meson from the birth of the theory throughout his life. The HLS is originated from very nature of the nonlinear realization of the symmetry G based on the manifold G/H, and thus is universal to any physics based on the nonlinear realization. Here, I focus on the Higgs Lagrangian of the Standard Model (SM), which is shown to be equivalent to the nonlinear sigma model based on G/H = SU(2)L × SU(2)R/SU(2)V with additional symmetry, the nonlinearly-realized scale symmetry. Then, the SM does have a dynamical gauge boson of the SU(2)V HLS, "SM ρ meson", in addition to the Higgs as a pseudo-dilaton as well as the NG bosons to be absorbed in to the W and Z. Based on the recent work done with Matsuzaki and Ohki, I discuss a novel possibility that the SM ρ meson acquires kinetic term by the SM dynamics itself, which then stabilizes the skyrmion dormant in the SM as a viable candidate for the dark matter, what we call "dark SM skyrmion (DSMS)".

  3. Constraining solar hidden photons using HPGe detector

    Energy Technology Data Exchange (ETDEWEB)

    Horvat, R.; Kekez, D., E-mail: Dalibor.Kekez@irb.hr; Krčmar, M.; Krečak, Z.; Ljubičić, A.

    2013-04-25

    In this Letter we report on the results of our search for photons from a U(1) gauge factor in the hidden sector of the full theory. With our experimental setup we observe the single spectrum in a HPGe detector arising as a result of the photoelectric-like absorption of hidden photons emitted from the Sun on germanium atoms inside the detector. The main ingredient of the theory used in our analysis, a severely constrained kinetic mixing from the two U(1) gauge factors and massive hidden photons, entails both photon into hidden state oscillations and a minuscule coupling of hidden photons to visible matter, of which the latter our experimental setup has been designed to observe. On a theoretical side, full account was taken of the effects of refraction and damping of photons while propagating in Sun's interior as well as in the detector. We exclude hidden photons with kinetic couplings χ>(2.2×10{sup −13}–3×10{sup −7}) in the mass region 0.2 eV≲m{sub γ{sup ′}}≲30 keV. Our constraints on the mixing parameter χ in the mass region from 20 eV up to 15 keV prove even slightly better then those obtained recently by using data from the CAST experiment, albeit still somewhat weaker than those obtained from solar and HB stars lifetime arguments.

  4. Exploring triad-rich substructures by graph-theoretic characterizations in complex networks

    Science.gov (United States)

    Jia, Songwei; Gao, Lin; Gao, Yong; Nastos, James; Wen, Xiao; Zhang, Xindong; Wang, Haiyang

    2017-02-01

    One of the most important problems in complex networks is how to detect communities accurately. The main challenge lies in the fact that traditional definition about communities does not always capture the intrinsic features of communities. Motivated by the observation that communities in PPI networks tend to consist of an abundance of interacting triad motifs, we define a 2-club substructure with diameter 2 possessing triad-rich property to describe a community. Based on the triad-rich substructure, we design a DIVision Algorithm using our proposed edge Niche Centrality DIVANC to detect communities effectively in complex networks. We also extend DIVANC to detect overlapping communities by proposing a simple 2-hop overlapping strategy. To verify the effectiveness of triad-rich substructures, we compare DIVANC with existing algorithms on PPI networks, LFR synthetic networks and football networks. The experimental results show that DIVANC outperforms most other algorithms significantly and, in particular, can detect sparse communities.

  5. Exploring triad-rich substructures by graph-theoretic characterizations in complex networks

    CERN Document Server

    Jia, Songwei; Gao, Yong; Nastos, James; Wen, Xiao; Zhang, Xindong; Wang, Haiyang

    2016-01-01

    One of the most important problems in complex networks is how to detect metadata groups accurately. The main challenge lies in the fact that traditional structural communities do not always capture the intrinsic features of metadata groups. Motivated by the observation that metadata groups in PPI networks tend to consist of an abundance of interacting triad motifs, we define a 2-club substructure with diameter 2 which possessing triad-rich property to describe a metadata group. Based on the triad-rich substructure, we design a DIVision Algorithm using our proposed edge Niche Centrality DIVANC to detect metadata groups effectively in complex networks. We also extend DIVANC to detect overlapping metadata groups by proposing a simple 2-hop overlapping strategy. To verify the effectiveness of triad-rich substructures, we compare DIVANC with existing algorithms on PPI networks, LFR synthetic networks and football networks. The experimental results show that DIVANC outperforms most other algorithms significantly an...

  6. Exploring the reality of density substructures in the Palomar 5 stellar stream

    CERN Document Server

    Thomas, Guillaume F; Famaey, Benoit; Martin, Nicolas F; Lewis, Geraint F

    2016-01-01

    We present an analysis of the presence of substructures in the stellar stream of the Palomar 5 globular cluster, as derived from Sloan Digital Sky Survey data. Using a matched filter technique, we recover the positions and sizes of overdensities reported in previous studies. To explore the reality of these structures, we also create an artificial model of the stream, in which we construct a realistic background on top of which we add a perfectly smooth stream structure, taking into account the effects of photometric completeness and interstellar extinction. We find that the smooth artificial stream then shows similarly-pronounced substructures as the real structure. Interestingly, our best-fit N-body simulation does display real projected density variations linked to stellar epicyclic motions, but these become less significant when taking into account the SDSS star-count constraints. The substructures found when applying our matched filter technique to the N-body particles converted into observable stars are ...

  7. Theory and Simulations of Refractive Substructure in Resolved Scatter-Broadened Images

    CERN Document Server

    Johnson, Michael D

    2015-01-01

    At radio wavelengths, scattering in the interstellar medium distorts the appearance of astronomical sources. Averaged over a scattering ensemble, the result is a blurred image of the source. However, Narayan & Goodman (1989) and Goodman & Narayan (1989) showed that for an incomplete average, scattering introduces refractive substructure in the image of a point source that is both persistent and wideband. We show that this substructure is not smoothed by an extended source and that the scattering can therefore introduce spurious compact features into images that would be resolved in the absence of scattering. In addition, we derive efficient strategies to numerically compute realistic scattered images, and we present characteristic examples from simulations. Our results show that refractive substructure is an important consideration for ongoing missions at the highest angular resolutions, and we discuss specific implications for RadioAstron and the Event Horizon Telescope.

  8. Reconstruction of small-scale galaxy cluster substructure with lensing flexion

    Science.gov (United States)

    Cain, Benjamin; Bradač, Maruša; Levinson, Rebecca

    2016-09-01

    We present reconstructions of galaxy-cluster-scale mass distributions from simulated gravitational lensing data sets including strong lensing, weak lensing shear, and measurements of quadratic image distortions - flexion. The lensing data is constructed to make a direct comparison between mass reconstructions with and without flexion. We show that in the absence of flexion measurements, significant galaxy-group scale substructure can remain undetected in the reconstructed mass profiles, and that the resulting profiles underestimate the aperture mass in the substructure regions by ˜25 - 40%. When flexion is included, subhaloes down to a mass of ˜3 × 1012 M⊙ can be detected at an angular resolution smaller than 10″. Aperture masses from profiles reconstructed with flexion match the input distribution values to within an error of ˜13%, including both statistical error and scatter. This demonstrates the important constraint that flexion measurements place on substructure in galaxy clusters and its utility for producing high-fidelity mass reconstructions.

  9. Improving jet substructure in ATLAS using unified track and calorimeter information

    CERN Document Server

    Schramm, Steven; The ATLAS collaboration

    2017-01-01

    Jet substructure techniques play a critical role in ATLAS in searches for new physics, are increasingly important in measurements of the Standard Model, and are being utilized in the trigger. To date, ATLAS has mostly focused on the use of calorimeter-based jet substructure, which works well for jets initiated by particles with low to moderate boost, but which lacks the angular resolution needed to resolve the desired substructure in the highly-boosted regime. We will present a novel approach designed to mitigate the calorimeter angular resolution limitations, thus providing superior performance to prior methods. Similar to previous methods, the superior angular resolution of the tracker is combined with information from the calorimeters. However, the new method is fundamentally different, as it correlates low-level objects as tracks and individual energy deposits in the calorimeter, before running any jet finding algorithms. The resulting objects are used as inputs to jet reconstruction, and in turn result i...

  10. Improving jet substructure performance in ATLAS using Track-CaloClusters

    CERN Document Server

    The ATLAS collaboration

    2017-01-01

    Jet substructure techniques play a critical role in ATLAS in searches for new physics, are increasingly important in measurements of the Standard Model, and are being utilized in the trigger. To date, ATLAS has mostly focused on the use of calorimeter-based jet substructure, which works well for jets initiated by particles with low to moderate boost, but which lacks the angular resolution needed to resolve the desired substructure in the highly-boosted regime. We present a novel approach designed to mitigate the calorimeter angular resolution limitations, thus providing superior performance to prior methods. Similarly to the previously developed combined mass technique, the superior angular resolution of the tracker is combined with information from the calorimeters. However, the new method is fundamentally different, as it correlates low-level objects such as tracks and individual energy deposits in the calorimeter, before running any jet finding algorithms. The resulting objects are used as inputs to jet re...

  11. Jet Substructure Templates: Data-driven QCD Backgrounds for Fat Jet Searches

    CERN Document Server

    Cohen, Timothy; Lisanti, Mariangela; Lou, Hou Keong; Wacker, Jay G

    2014-01-01

    QCD is often the dominant background to new physics searches for which jet substructure provides a useful handle. Due to the challenges associated with modeling this background, data-driven approaches are necessary. This paper presents a novel method for determining QCD predictions using templates -- probability distribution functions for jet substructure properties as a function of kinematic inputs. Templates can be extracted from a control region and then used to compute background distributions in the signal region. Using Monte Carlo, we illustrate the procedure with two case studies and show that the template approach effectively models the relevant QCD background. This work strongly motivates the application of these techniques to LHC data.

  12. Jet substructure templates: data-driven QCD backgrounds for fat jet searches

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, Timothy [Theory Group, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Jankowiak, Martin [Institut für Theoretische Physik, Universität Heidelberg, 69120 Heidelberg (Germany); Lisanti, Mariangela; Lou, Hou Keong [Physics Department, Princeton University, Princeton, NJ 08544 (United States); Wacker, Jay G. [Theory Group, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)

    2014-05-05

    QCD is often the dominant background to new physics searches for which jet substructure provides a useful handle. Due to the challenges associated with modeling this background, data-driven approaches are necessary. This paper presents a novel method for determining QCD predictions using templates — probability distribution functions for jet substructure properties as a function of kinematic inputs. Templates can be extracted from a control region and then used to compute background distributions in the signal region. Using Monte Carlo, we illustrate the procedure with two case studies and show that the template approach effectively models the relevant QCD background. This work strongly motivates the application of these techniques to LHC data.

  13. OPTIMAL SUBSTRUCTURE OF SET-VALUED SOLUTIONS OF NORMAL-FORM GAMES AND COORDINATION

    Institute of Scientific and Technical Information of China (English)

    Norimasa KOBAYASHI; Kyoichi KIJIMA

    2009-01-01

    A number of solution concepts of normal-form games have been proposed in the literature on subspaces of action profiles that have Nash type stability. While the literature mainly focuses on the minimal of such stable subspaces, this paper argues that non-minimal stable subspaces represent well the multi-agent situations to which neither Nash equilibrium nor rationalizability may be applied with satisfaction. As a theoretical support, the authors prove the optimal substructure of stable subspaces regarding the restriction of a game. It is further argued that the optimal substructure characterizes hierarchical diversity of coordination and interim phases in learning.

  14. Performance of Jet Substructure Techniques and Boosted Object Identification in ATLAS

    CERN Document Server

    Lacey, J; The ATLAS collaboration

    2014-01-01

    ATLAS has implemented and commissioned many new jet substructure techniques to aid in the identification and interpretation of hadronic final states originating from Lorentz-boosted heavy particles produced at the LHC. These techniques include quantum jets, jet charge, jet shapes, quark/gluon, boosted boson and top quark tagging, along with grooming methods such as pruning, trimming, and filtering. These techniques have been validated using the large 2012 ATLAS dataset. Presented here is a summary of the state of the art jet substructure and tagging techniques developed in ATLAS, their performance and recent results.

  15. Substructure evolution of Zircaloy-4 during creep and implications for the Modified Jogged-Screw model

    Energy Technology Data Exchange (ETDEWEB)

    Morrow, B.M., E-mail: morrow@lanl.gov [The Ohio State University, 2041 College Rd., 477 Watts Hall, Columbus, OH 43210 (United States); Los Alamos National Laboratory, P.O. Box 1663, MS G755, Los Alamos, NM 87545 (United States); Kozar, R.W.; Anderson, K.R. [Bettis Laboratory, Bechtel Marine Propulsion Corp., West Mifflin, PA 15122 (United States); Mills, M.J., E-mail: millsmj@mse.osu.edu [The Ohio State University, 2041 College Rd., 477 Watts Hall, Columbus, OH 43210 (United States)

    2016-05-17

    Several specimens of Zircaloy-4 were creep tested at a single stress-temperature condition, and interrupted at different accumulated strain levels. Substructural observations were performed using bright field scanning transmission electron microscopy (BF STEM). The dislocation substructure was characterized to ascertain how creep strain evolution impacts the Modified Jogged-Screw (MJS) model, which has previously been utilized to predict steady-state strain rates in Zircaloy-4. Special attention was paid to the evolution of individual model parameters with increasing strain. Results of model parameter measurements are reported and discussed, along with possible extensions to the MJS model.

  16. VARIATION OF SUBSTRUCTURES OF PEARLITIC HEAT RESISTANT STEEL AFTER HIGH TEMPERATURE AGING

    Institute of Scientific and Technical Information of China (English)

    R.C.Yang; K.Chen; H.X.Feng; H.Wang

    2004-01-01

    The observations of dislocations, substructures and other microstructural details were conducted mainly by means of transmission electron microscope (TEM) and scanning electron microscope (SEM) for 12Cr1Mo V pearlitic heat-resistant steel. It is shown that during the high temperature long-term aging, the disordered and jumbled phasetransformed dislocations caused by normalized cooling are recovered and rearranged into cell substructures, and then the dislocation density is reduced gradually. Finally a low density linear dislocation configuration and a stabler dislocation network are formed and ferritic grains grow considerably.

  17. Probing hidden sector photons through the Higgs window

    Energy Technology Data Exchange (ETDEWEB)

    Ahlers, M. [Oxford Univ. (United Kingdom). Rudolf Peierls Centre for Theoretical Physics; Jaeckel, J. [Durham Univ. (United Kingdom). Inst. for Particle Physics and Phenomenology; Redondo, J.; Ringwald, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2008-07-15

    We investigate the possibility that a (light) hidden sector extra photon receives its mass via spontaneous symmetry breaking of a hidden sector Higgs boson, the so-called hidden-Higgs. The hidden-photon can mix with the ordinary photon via a gauge kinetic mixing term. The hidden-Higgs can couple to the Standard Model Higgs via a renormalizable quartic term - sometimes called the Higgs Portal. We discuss the implications of this light hidden-Higgs in the context of laser polarization and light-shining-through-the-wall experiments as well as cosmological, astrophysical, and non-Newtonian force measurements. For hidden-photons receiving their mass from a hidden-Higgs we find in the small mass regime significantly stronger bounds than the bounds on massive hidden sector photons alone. (orig.)

  18. Agronomic biofortification of crops to fight hidden hunger in sub-Saharan Africa

    NARCIS (Netherlands)

    Valença, de A.W.; Bake, A.; Brouwer, I.D.; Giller, K.E.

    2017-01-01

    Micronutrient deficiencies or ‘hidden hunger’ resulting from unbalanced diets based on starchy staple crops are prevalent among the population of sub-Saharan Africa. This review discusses the effectiveness of agronomic biofortification - the application of mineral micronutrient fertilizers to soils

  19. Agronomic biofortification of crops to fight hidden hunger in sub-Saharan Africa

    NARCIS (Netherlands)

    Valença, de A.W.; Bake, A.; Brouwer, I.D.; Giller, K.E.

    2017-01-01

    Micronutrient deficiencies or ‘hidden hunger’ resulting from unbalanced diets based on starchy staple crops are prevalent among the population of sub-Saharan Africa. This review discusses the effectiveness of agronomic biofortification - the application of mineral micronutrient fertilizers to soils

  20. Hidden Costs of Hospital Based Delivery from Two Tertiary Hospitals in Western Nepal.

    Science.gov (United States)

    Acharya, Jeevan; Kaehler, Nils; Marahatta, Sujan Babu; Mishra, Shiva Raj; Subedi, Sudarshan; Adhikari, Bipin

    2016-01-01

    critical factor for many poor and remote households who attend the hospital for delivery. Current remuneration (10-15 USD for normal delivery, 30 USD for complicated delivery and 70 USD for caesarean section delivery) for maternity incentive needs to account the hidden costs by increasing it to 250 USD for normal delivery and 350 USD for C-section. Decentralization of the obstetric care to remote and under-privileged population might reduce the economic burden of pregnant women and can facilitate their attendance at the health care centers.

  1. Hidden Costs of Hospital Based Delivery from Two Tertiary Hospitals in Western Nepal.

    Directory of Open Access Journals (Sweden)

    Jeevan Acharya

    critical factor for many poor and remote households who attend the hospital for delivery. Current remuneration (10-15 USD for normal delivery, 30 USD for complicated delivery and 70 USD for caesarean section delivery for maternity incentive needs to account the hidden costs by increasing it to 250 USD for normal delivery and 350 USD for C-section. Decentralization of the obstetric care to remote and under-privileged population might reduce the economic burden of pregnant women and can facilitate their attendance at the health care centers.

  2. A Substructural Damage Identification Approach for Shear Structure Based on Changes in the First AR Model Coefficient Matrix

    Directory of Open Access Journals (Sweden)

    Liu Mei

    2015-01-01

    Full Text Available A substructural damage identification approach based on changes in the first AR model coefficient matrix is proposed in this paper to identify structural damage including its location and severity. Firstly, a substructure approach is adopted in the procedure to divide a complete structure into several substructures in order to significantly reduce the number of unknown parameters for each substructure so that damage identification processes can be independently conducted on each substructure. To establish a relation between changes in AR model coefficients and structural damage for each substructure, a theoretical derivation is presented. Thus the accelerations are fed into ARMAX models to determine the AR model coefficients for each substructure under undamaged and various damaged conditions, based on which changes in the first AR model coefficient matrix (CFAR is obtained and adopted as the damage indicator for the proposed substructure damage identification approach. To better assess the performance of the proposed procedure, a numerical simulation and an experimental verification of the proposed approach are then carried out and the results show that the proposed procedure can successfully locate and quantify the damage in both simulation and laboratory experiment.

  3. Lepton mixing from the hidden sector

    CERN Document Server

    Ludl, P O

    2015-01-01

    Experimental results indicate a possible relation between the lepton and quark mixing matrices of the form U_PMNS \\approx V_CKM^\\dagger U_X, where U_X is a matrix with special structure related to the mechanism of neutrino mass generation. We propose a framework which can realize such a relation. The main ingredients of the framework are the double seesaw mechanism, SO(10) Grand Unification and a hidden sector of theory. The latter is composed of singlets (fermions and bosons) of the GUT symmetry with masses between the GUT and Planck scale. The interactions in this sector obey certain symmetries G_hidden. We explore the conditions under which symmetries G_hidden can produce flavour structures in the visible sector. Here the key elements are the basis-fixing symmetry and mediators which communicate information about properties of the hidden sector to the visible one. The interplay of SO(10) symmetry, basis-fixing symmetry identified as Z2 x Z2 and G_hidden can lead to the required form of U_X. A different kin...

  4. Fitting Hidden Markov Models to Psychological Data

    Directory of Open Access Journals (Sweden)

    Ingmar Visser

    2002-01-01

    Full Text Available Markov models have been used extensively in psychology of learning. Applications of hidden Markov models are rare however. This is partially due to the fact that comprehensive statistics for model selection and model assessment are lacking in the psychological literature. We present model selection and model assessment statistics that are particularly useful in applying hidden Markov models in psychology. These statistics are presented and evaluated by simulation studies for a toy example. We compare AIC, BIC and related criteria and introduce a prediction error measure for assessing goodness-of-fit. In a simulation study, two methods of fitting equality constraints are compared. In two illustrative examples with experimental data we apply selection criteria, fit models with constraints and assess goodness-of-fit. First, data from a concept identification task is analyzed. Hidden Markov models provide a flexible approach to analyzing such data when compared to other modeling methods. Second, a novel application of hidden Markov models in implicit learning is presented. Hidden Markov models are used in this context to quantify knowledge that subjects express in an implicit learning task. This method of analyzing implicit learning data provides a comprehensive approach for addressing important theoretical issues in the field.

  5. Probing Hidden Sector Photons through the Higgs Window.

    OpenAIRE

    Ahlers, M.; Jaeckel, J; Redondo, J.; Ringwald, A.

    2008-01-01

    We investigate the possibility that a (light) hidden sector extra photon receives its mass via spontaneous symmetry breaking of a hidden sector Higgs boson, the so-called hidden-Higgs. The hidden-photon can mix with the ordinary photon via a gauge kinetic mixing term. The hidden-Higgs can couple to the Standard Model Higgs via a renormalizable quartic term - sometimes called the Higgs Portal. We discuss the implications of this light hidden-Higgs in the context of laser polarization and light...

  6. Supersymmetric leptogenesis and light hidden sectors

    CERN Document Server

    Weniger, Christoph

    2010-01-01

    Thermal leptogenesis and supergravity are attractive scenarios for physics beyond the standard model. However, it is well known that the super-weak interaction of the gravitino often leads to problems with primordial nucleosynthesis in the standard scenario of matter parity conserving MSSM + three right-handed neutrinos. We will present and compare two related solutions to these problems: 1) The conflict between BBN and leptogenesis can be avoided in presence of a hidden sector with light supersymmetric particles which open new decay channels for the dangerous long-lived particles. 2) If there is a condensate in the hidden sector, such additional decay channels can be alternatively opened by dynamical breaking of matter parity in the hidden sector.

  7. The development of microtextures and dislocation substructures in naturally deformed olivines from various geological environments

    NARCIS (Netherlands)

    Buiskool Toxopeus, J.M.A.

    1978-01-01

    High voltage electron microscopy and petrofabric analysis techniques are used to distinguish dislocation substructures and preferred orientation patterns of the mineral olivine in naturally deformed peridotites. In order to obtain information over a wide field in which different types of deformation

  8. Property Graph vs RDF Triple Store: A Comparison on Glycan Substructure Search.

    Directory of Open Access Journals (Sweden)

    Davide Alocci

    Full Text Available Resource description framework (RDF and Property Graph databases are emerging technologies that are used for storing graph-structured data. We compare these technologies through a molecular biology use case: glycan substructure search. Glycans are branched tree-like molecules composed of building blocks linked together by chemical bonds. The molecular structure of a glycan can be encoded into a direct acyclic graph where each node represents a building block and each edge serves as a chemical linkage between two building blocks. In this context, Graph databases are possible software solutions for storing glycan structures and Graph query languages, such as SPARQL and Cypher, can be used to perform a substructure search. Glycan substructure searching is an important feature for querying structure and experimental glycan databases and retrieving biologically meaningful data. This applies for example to identifying a region of the glycan recognised by a glycan binding protein (GBP. In this study, 19,404 glycan structures were selected from GlycomeDB (www.glycome-db.org and modelled for being stored into a RDF triple store and a Property Graph. We then performed two different sets of searches and compared the query response times and the results from both technologies to assess performance and accuracy. The two implementations produced the same results, but interestingly we noted a difference in the query response times. Qualitative measures such as portability were also used to define further criteria for choosing the technology adapted to solving glycan substructure search and other comparable issues.

  9. Updating failure probability of a welded joint in offshore wind turbine substructures

    DEFF Research Database (Denmark)

    Mai, Quang A.; Sørensen, John Dalsgaard; Rigo, Philippe

    2016-01-01

    The operation and maintenance cost of offshore wind turbine substructures contributes significantly in the cost of a kWh. That cost may be lowered by application of reliability- and risk based maintenance strategies and reliability updating based on inspections performed during the design lifetim...

  10. Free-Interface Dual-Compatibility Modal Synthesis Substructure Method in Large-Scale Structures

    Institute of Scientific and Technical Information of China (English)

    Peng Guihan彭桂瀚; Lin Wei林伟; Chen Shanghong陈尚鸿; Yu Jiexin余洁歆

    2015-01-01

    Free-interface dual-compatibility modal synthesis method(compatibility of both force and displacement on interfaces)is introduced to large-scale civil engineering structure to enhance computation efficiency. The basic equations of the method are first set up, and then the mode cut-off principle and the dividing principle are proposed. MATLAB is used for simulation in different frame structures. The simulation results demonstrate the applicability of this substructure method to civil engineering structures and the correctness of the proposed mode cut-off princi-ple. Studies are also conducted on how to divide the whole structure for better computation efficiency while main-taining better precision. It is observed that the geometry and material properties should be considered, and the syn-thesis results would be more precise when the inflection points of the mode shapes are taken into consideration. Furthermore, the simulation performed on a large-scale high-rise connected structure further proves the feasibility and efficiency of this modal synthesis method compared with the traditional global method. It is also concluded from the simulation results that the fewer number of DOFs in each substructure will result in better computation efficiency, but too many substructures will be time-consuming due to the tedious synthesis procedures. Moreover, the substructures with free interface will introduce errors and reduce the precision dramatically, which should be avoided.

  11. A model for Quick Load Analysis for monopile-type offshore wind turbine substructures

    DEFF Research Database (Denmark)

    Schløer, Signe; Castillo, Laura Garcia; Fejerskov, Morten

    2016-01-01

    A model for Quick Load Analysis, QuLA, of an offshore wind turbine substructure is presented. The aerodynamic rotor loads and damping are precomputed for a load-based configuration. The dynamic structural response is represented by the first global fore-aft mode only and is computed in the freque...

  12. Loop substructure identification for shear structures of unknown structural mass using synthesized references

    Science.gov (United States)

    Zhang, Dongyu; Li, Hui

    2017-08-01

    Shear structure is widely adopted to model the dynamics for building structures. Thus, developing accurate and efficient parameter identification methods for a shear structure plays a crucial role in structural health monitoring for building structures. In the authors’ previous studies, a loop substructure identification (LSI) method was proposed for shear structures, in which the dynamic equation of a two-story substructure is utilized to establish a loop identification sequence, directly estimating the substructure’s parameters. To ensure the convergence of the loop identification sequence, some structural control (SC) systems are needed to change the critical structural responses in a favorable way. However, the limited availability of SC systems in general buildings restrains the wide application of this controlled loop substructure identification (CLSI) method. In this paper, the original LSI method is first reformed, which can perform the LSI even if the structural mass is unknown. Then, a new reference selection method is proposed to make the LSI method converge without the help of SC systems. Different synthesized reference responses, formed by a weighted linear combination of measured structural responses, are used to formulate the LSI sequence. Next, an optimization strategy is proposed to determine the optimal weighting factors of the synthesized reference responses, which makes the LSI converged. Finally, the LSI is carried out for a 20-story shear structure, the identification results of which show that the proposed LSI method, combined with the proposed reference selection method, can very accurately estimate the substructure parameters of the shear structure.

  13. Placing Limits on Extragalactic Substructure with Gravitational Lenses and Adaptive Optics

    NARCIS (Netherlands)

    Lagattuta, David J.; Vegetti, S.; Auger, M. W.; Fassnacht, C. D.; Koopmans, L. V. E.; McKean, J. P.

    2011-01-01

    We present the first results from a systematic search for extragalactic substructure, using high resolution Adaptive Optics (AO) images of known strong gravitational lenses. In particular we focus on two lens systems, B0128+437 and B1939+666, placing limits on both luminous and dark matter substruct

  14. A New Method to Quantify X-ray Substructures in Clusters of Galaxies

    CERN Document Server

    Andrade-Santos, Felipe; Laganá, Tatiana Ferraz

    2011-01-01

    We present a new method to quantify substructures in clusters of galaxies, based on the analysis of the intensity of structures. This analysis is done in a residual image that is the result of the subtraction of a surface brightness model, obtained by fitting a two-dimensional analytical model (beta-model or S\\'ersic profile) with elliptical symmetry, from the X-ray image. Our method is applied to 34 clusters observed by the Chandra Space Telescope that are in the redshift range 0.02substructure level with physical quantities, such as the mass, X-ray luminosity, temperature, and cluster redshift. We use our method to separate the clusters in two sub-samples of high and low substructure levels. We conclude, using Monte Carlo simulations, that the method recuperates very well the true amount of substructure for small angular core radii clusters (with respect to the whole image s...

  15. Substructure method of soil-structure interaction analysis for earthquake loadings

    Energy Technology Data Exchange (ETDEWEB)

    Park, H. G.; Joe, Y. H. [Industrial Development Research Center, Univ. of Incheon, Incheon (Korea, Republic of)

    1997-07-15

    Substructure method has been preferably adopted for soil-structure interaction analysis because of its simplicity and economy in practical application. However, substructure method has some limitation in application and does not always give reliable results especially for embedded structures or layered soil conditions. The objective of this study to validate the reliability of the soil-structure interaction analysis results by the proposed substructure method using lumped-parameter model and suggest a method of seismic design of nuclear power plant structures with specific design conditions. In this study, theoretic background and modeling technique of soil-structure interaction phenomenon have been reviewed and an analysis technique based on substructure method using lumped-parameter model has been suggested. The practicality and reliability of the proposed method have been validated through the application of the method to the seismic analysis of the large-scale seismic test models. A technical guide for practical application and evaluation of the proposed method have been also provided through the various type parametric.

  16. Property Graph vs RDF Triple Store: A Comparison on Glycan Substructure Search.

    Science.gov (United States)

    Alocci, Davide; Mariethoz, Julien; Horlacher, Oliver; Bolleman, Jerven T; Campbell, Matthew P; Lisacek, Frederique

    2015-01-01

    Resource description framework (RDF) and Property Graph databases are emerging technologies that are used for storing graph-structured data. We compare these technologies through a molecular biology use case: glycan substructure search. Glycans are branched tree-like molecules composed of building blocks linked together by chemical bonds. The molecular structure of a glycan can be encoded into a direct acyclic graph where each node represents a building block and each edge serves as a chemical linkage between two building blocks. In this context, Graph databases are possible software solutions for storing glycan structures and Graph query languages, such as SPARQL and Cypher, can be used to perform a substructure search. Glycan substructure searching is an important feature for querying structure and experimental glycan databases and retrieving biologically meaningful data. This applies for example to identifying a region of the glycan recognised by a glycan binding protein (GBP). In this study, 19,404 glycan structures were selected from GlycomeDB (www.glycome-db.org) and modelled for being stored into a RDF triple store and a Property Graph. We then performed two different sets of searches and compared the query response times and the results from both technologies to assess performance and accuracy. The two implementations produced the same results, but interestingly we noted a difference in the query response times. Qualitative measures such as portability were also used to define further criteria for choosing the technology adapted to solving glycan substructure search and other comparable issues.

  17. Substructure formation during pattern transposition from substrate into polymer blend film

    NARCIS (Netherlands)

    Cyganik, P; Budkowski, A; Steiner, U; Rysz, J; Bernasik, A; Walheim, S; Postawa, Z; Raczkowska, J

    2003-01-01

    A chemical pattern on a substrate is transposed into thin films of a ternary polymer blend during spin-casting from a common solvent. One of the blend components intercalates at interfaces between the other two phases to reduce their interfacial energy. As a result, an extensive substructure is form

  18. Structure and substructure of austenite formed during heating of quenched and thermomechanically strengthened steels

    Energy Technology Data Exchange (ETDEWEB)

    Bernshtejn, M.L.; Kaputkina, L.M.; Prokoshkin, S.D.; Lyuttsau, A.V.; Prokoshkina, V.G. (Moskovskij Inst. Stali i Splavov (USSR))

    1982-06-01

    Mechanism of ..cap alpha.. ..-->.. ..gamma.. transformation in chromium and chromium-nickel steels, peculiarities of substructure formation of austenite formed at repeated heating after quenching and high-temperature thermomechanical treatment and its stability to recrystallization in steels with different martensite morphology and temperature of the initial stage of austenite formation are investigated.

  19. The tension between organisational sub-structures in secondary schools and educational reform

    NARCIS (Netherlands)

    Imants, J.G.M.; Sleegers, P.J.C.; Witziers, B.

    2001-01-01

    In Dutch secondary schools the recent trend has been to replace the two existing sub-structures of subject departments and student guidance units by one system of integrated and decentralised teams. The aim of this article is to gain more insight into how secondary schools can provide supportive wor

  20. Quantifying Substructure Measures In X-ray Images of Galaxy Cluster Mergers With SLAM

    Science.gov (United States)

    Chatzikos, Marios; Sarazin, C. L.; O'Shea, B. W.

    2014-01-01

    I use the Simulation Library of Astrophysical galaxy cluster Mergers (SLAM) database to quantify the effects of mergers on X-ray observables. SLAM consists of a set of 156 adiabatic simulations of binary galaxy cluster mergers, that covers 2 orders of magnitude in the mass of the primary cluster, four values for the mass contrast, and four values for the angular momentum of the collision. In this talk I describe results on substructure measures obtained for various viewing angles. I have quantified the substructure in X-ray images using both center shifts and power ratios. Mergers of intermediate mass contrasts produce substructure signals that can persist in X-ray images for at least 1-2 sound crossing times. The amplitude of both measures depends strongly on the initial mass contrast. The measures for major mergers (mass contrast less than 3) appear to depend on the system mass, while for minor mergers (mass contrast between 3 and 10) they are generally independent of the system mass. Neither measure reflects the true dynamical state of the system closely, although the center shifts appear to be a better proxy. Comparisons with the virial and hydrostatic disequilibrium parameters reveal that there is no value of either substructure measure that unambiguously distinguishes merging from relaxing systems. Implications for SZE observations will also be discussed.

  1. Can galactic dark matter substructure contribute to the cosmic gamma-ray anisotropy?

    CERN Document Server

    Lange, J U

    2014-01-01

    The annihilation of dark matter (DM) particles in the Milky Way can contribute to the diffuse gamma-ray background (DGRB). Due to the presence of substructures, this emission will appear anisotropic in a predictable way. We generate full-sky maps of the gamma-ray emission in galactic substructures from results of the high-resolution Via Lactea II N-body simulation of the Milky Way DM halo. We calculate the anisotropy pattern, taking into account different radial profiles of the DM distribution in substructures, cosmic variance, and the detection threshold, and compare it to the anisotropy in the DGRB observed by the Fermi Large Area Telescope (LAT). By comparing the upper limits on the DM self-annihilation cross-section, , implied by the anisotropy to the intensity of the DGRB and detected sources in the LAT 2-yr Point Source Catalog, we find that galactic substructure cannot contribute to the anisotropies in the DGRB without strongly violating these observations. Our results challenge the perception that sma...

  2. Substructure formation during pattern transposition from substrate into polymer blend film

    NARCIS (Netherlands)

    Cyganik, P; Budkowski, A; Steiner, U; Rysz, J; Bernasik, A; Walheim, S; Postawa, Z; Raczkowska, J

    2003-01-01

    A chemical pattern on a substrate is transposed into thin films of a ternary polymer blend during spin-casting from a common solvent. One of the blend components intercalates at interfaces between the other two phases to reduce their interfacial energy. As a result, an extensive substructure is form

  3. The evolution of binary populations in cool, clumpy star clusters

    CERN Document Server

    Parker, Richard J; Allison, Richard J

    2011-01-01

    Observations and theory suggest that star clusters can form in a subvirial (cool) state and are highly substructured. Such initial conditions have been proposed to explain the level of mass segregation in clusters through dynamics, and have also been successful in explaining the origin of trapezium-like systems. In this paper we investigate, using N-body simulations, whether such a dynamical scenario is consistent with the observed binary properties in the Orion Nebula Cluster (ONC). We find that several different primordial binary populations are consistent with the overall fraction and separation distribution of visual binaries in the ONC (in the range 67 - 670 au), and that these binary systems are heavily processed. The substructured, cool-collapse scenario requires a primordial binary fraction approaching 100 per cent. We find that the most important factor in processing the primordial binaries is the initial level of substructure; a highly substructured cluster processes up to 20 per cent more systems t...

  4. Hidden Markov models estimation and control

    CERN Document Server

    Elliott, Robert J; Moore, John B

    1995-01-01

    As more applications are found, interest in Hidden Markov Models continues to grow. Following comments and feedback from colleagues, students and other working with Hidden Markov Models the corrected 3rd printing of this volume contains clarifications, improvements and some new material, including results on smoothing for linear Gaussian dynamics. In Chapter 2 the derivation of the basic filters related to the Markov chain are each presented explicitly, rather than as special cases of one general filter. Furthermore, equations for smoothed estimates are given. The dynamics for the Kalman filte

  5. Hidden simplicity of gauge theory amplitudes

    Energy Technology Data Exchange (ETDEWEB)

    Drummond, J M, E-mail: drummond@lapp.in2p3.f [LAPTH, Universite de Savoie, CNRS, B.P. 110, F-74941 Annecy-le-Vieux, Cedex (France)

    2010-11-07

    These notes were given as lectures at the CERN Winter School on Supergravity, Strings and Gauge Theory 2010. We describe the structure of scattering amplitudes in gauge theories, focussing on the maximally supersymmetric theory to highlight the hidden symmetries which appear. Using the Britto, Cachzo, Feng and Witten (BCFW) recursion relations we solve the tree-level S-matrix in N=4 super Yang-Mills theory and describe how it produces a sum of invariants of a large symmetry algebra. We review amplitudes in the planar theory beyond tree level, describing the connection between amplitudes and Wilson loops, and discuss the implications of the hidden symmetries.

  6. Hidden simplicity of gauge theory amplitudes

    Science.gov (United States)

    Drummond, J. M.

    2010-11-01

    These notes were given as lectures at the CERN Winter School on Supergravity, Strings and Gauge Theory 2010. We describe the structure of scattering amplitudes in gauge theories, focussing on the maximally supersymmetric theory to highlight the hidden symmetries which appear. Using the Britto, Cachzo, Feng and Witten (BCFW) recursion relations we solve the tree-level S-matrix in \\ {N}=4 super Yang-Mills theory and describe how it produces a sum of invariants of a large symmetry algebra. We review amplitudes in the planar theory beyond tree level, describing the connection between amplitudes and Wilson loops, and discuss the implications of the hidden symmetries.

  7. Hidden neural networks: application to speech recognition

    DEFF Research Database (Denmark)

    Riis, Søren Kamaric

    1998-01-01

    We evaluate the hidden neural network HMM/NN hybrid on two speech recognition benchmark tasks; (1) task independent isolated word recognition on the Phonebook database, and (2) recognition of broad phoneme classes in continuous speech from the TIMIT database. It is shown how hidden neural networks...... (HNNs) with much fewer parameters than conventional HMMs and other hybrids can obtain comparable performance, and for the broad class task it is illustrated how the HNN can be applied as a purely transition based system, where acoustic context dependent transition probabilities are estimated by neural...

  8. Dark Radiation from a hidden U(1)

    CERN Document Server

    Vogel, Hendrik

    2015-01-01

    We discuss the impact of a hidden sector consisting of Minicharged Particles (MCPs) and massless hidden photons on the expansion history of our Universe. We present parameter scans for the amount of extra relativistic particles (Neff) and the abundance of light nuclei for fermionic MCPs with masses between ~100 keV and 10 GeV and minicharges in the range 10^(-11)-1. Current CMB and BBN data significantly constrain the available parameter space of MCPs. The shown results are a valuable indicator for future experimental searches and are presented in a flexible way so that more accurate results on Neff can be easily interpreted.

  9. Hidden Symmetries, Central Charges and All That

    CERN Document Server

    de Wit, Bernard; Wit, Bernard de; Nicolai, Hermann

    2001-01-01

    In this review we discuss hidden symmetries of toroidal compactifications of eleven-dimensional supergravity. We recall alternative versions of this theory which exhibit traces of the hidden symmetries when still retaining the massive Kaluza-Klein states. We reconsider them in the broader perspective of M-theory which incorporates a more extended variety of BPS states. We also argue for a new geometry that may underly these theories. All our arguments point towards an extension of the number of space-time coordinates beyond eleven.

  10. Hidden Subgroup States are Almost Orthogonal

    CERN Document Server

    Ettinger, M; Knill, E H; Ettinger, Mark; Hoyer, Peter; Knill, Emanuel

    1999-01-01

    It is well known that quantum computers can efficiently find a hidden subgroup $H$ of a finite Abelian group $G$. This implies that after only a polynomial (in $\\log |G|$) number of calls to the oracle function, the states corresponding to different candidate subgroups have exponentially small inner product. We show that this is true for noncommutative groups also. We present a quantum algorithm which identifies a hidden subgroup of an arbitrary finite group $G$ in only a linear (in $\\log |G|$) number of calls to the oracle function. This is exponentially better than the best classical algorithm. However our quantum algorithm requires an exponential amount of time, as in the classical case.

  11. Searching for hidden sectors in multiparticle production at the LHC

    CERN Document Server

    Sanchis-Lozano, Miguel-Angel; Moreno-Picot, Salvador

    2015-01-01

    We study the impact of a hidden sector beyond the Standard Model, e.g. a Hidden Valley model, on factorial moments and cumulants of multiplicity distributions in multiparticle production with a special emphasis on the prospects for LHC results.

  12. Entropy Rate for Hidden Markov Chains with rare transitions

    OpenAIRE

    2010-01-01

    We consider Hidden Markov Chains obtained by passing a Markov Chain with rare transitions through a noisy memoryless channel. We obtain asymptotic estimates for the entropy of the resulting Hidden Markov Chain as the transition rate is reduced to zero.

  13. The Corporate Illiterates: The Hidden Illiterates of Silicon Valley.

    Science.gov (United States)

    Chase, Sharon

    1991-01-01

    Describes the writing and business communication problems of college-educated workers in Silicon Valley. Discusses hidden illiterates in the universities and in the workplace. Offers solutions for professors and managers faced with the problem of hidden illiterates. (PRA)

  14. Design and Implementation of Domain based Semantic Hidden Web Crawler

    OpenAIRE

    Manvi; Bhatia, Komal Kumar; Dixit, Ashutosh

    2015-01-01

    Web is a wide term which mainly consists of surface web and hidden web. One can easily access the surface web using traditional web crawlers, but they are not able to crawl the hidden portion of the web. These traditional crawlers retrieve contents from web pages, which are linked by hyperlinks ignoring the information hidden behind form pages, which cannot be extracted using simple hyperlink structure. Thus, they ignore large amount of data hidden behind search forms. This paper emphasizes o...

  15. Effect of Soil-Structure Interaction on Seismic Performance of Long-Span Bridge Tested by Dynamic Substructuring Method

    Directory of Open Access Journals (Sweden)

    Zhenyun Tang

    2017-01-01

    Full Text Available Because of the limitations of testing facilities and techniques, the seismic performance of soil-structure interaction (SSI system can only be tested in a quite small scale model in laboratory. Especially for long-span bridge, a smaller tested model is required when SSI phenomenon is considered in the physical test. The scale effect resulting from the small scale model is always coupled with the dynamic performance, so that the seismic performance of bridge considering SSI effect cannot be uncovered accurately by the traditional testing method. This paper presented the implementation of real-time dynamic substructuring (RTDS, involving the combined use of shake table array and computational engines for the seismic simulation of SSI. In RTDS system, the bridge with soil-foundation system is divided into physical and numerical substructures, in which the bridge is seen as physical substructures and the remaining part is seen as numerical substructures. The interface response between the physical and numerical substructures is imposed by shake table and resulting reaction force is fed back to the computational engine. The unique aspect of the method is to simulate the SSI systems subjected to multisupport excitation in terms of a larger physical model. The substructuring strategy and the control performance associated with the real-time substructuring testing for SSI were performed. And the influence of SSI on a long-span bridge was tested by this novel testing method.

  16. Variational Hidden Conditional Random Fields with Coupled Dirichlet Process Mixtures

    NARCIS (Netherlands)

    Bousmalis, K.; Zafeiriou, S.; Morency, L.P.; Pantic, Maja; Ghahramani, Z.

    2013-01-01

    Hidden Conditional Random Fields (HCRFs) are discriminative latent variable models which have been shown to successfully learn the hidden structure of a given classification problem. An infinite HCRF is an HCRF with a countably infinite number of hidden states, which rids us not only of the necessit

  17. Perceptual consequences of "hidden" hearing loss.

    Science.gov (United States)

    Plack, Christopher J; Barker, Daphne; Prendergast, Garreth

    2014-09-09

    Dramatic results from recent animal experiments show that noise exposure can cause a selective loss of high-threshold auditory nerve fibers without affecting absolute sensitivity permanently. This cochlear neuropathy has been described as hidden hearing loss, as it is not thought to be detectable using standard measures of audiometric threshold. It is possible that hidden hearing loss is a common condition in humans and may underlie some of the perceptual deficits experienced by people with clinically normal hearing. There is some evidence that a history of noise exposure is associated with difficulties in speech discrimination and temporal processing, even in the absence of any audiometric loss. There is also evidence that the tinnitus experienced by listeners with clinically normal hearing is associated with cochlear neuropathy, as measured using Wave I of the auditory brainstem response. To date, however, there has been no direct link made between noise exposure, cochlear neuropathy, and perceptual difficulties. Animal experiments also reveal that the aging process itself, in the absence of significant noise exposure, is associated with loss of auditory nerve fibers. Evidence from human temporal bone studies and auditory brainstem response measures suggests that this form of hidden loss is common in humans and may have perceptual consequences, in particular, regarding the coding of the temporal aspects of sounds. Hidden hearing loss is potentially a major health issue, and investigations are ongoing to identify the causes and consequences of this troubling condition.

  18. The structural strength of glass: hidden damage

    NARCIS (Netherlands)

    Veer, F.A.; Rodichev, Y.M.

    2011-01-01

    We discuss “hidden damage” of glass by the rolling process, which results in heterogeneous distribution of microcracks on the edge surface of glass element, which are the fracture source deteriorating glass element strength. It is shown that removal of this damage on the edges of glass elements

  19. Discovering Hidden Treasures with GPS Technology

    Science.gov (United States)

    Nagel, Paul; Palmer, Roger

    2014-01-01

    "I found it!" Addison proudly proclaimed, as she used an iPhone and Global Positioning System (GPS) software to find the hidden geocache along the riverbank. Others in Lisa Bostick's fourth grade class were jealous, but there would be other geocaches to find. With the excitement of movies like "Pirates of the Caribbean" and…

  20. Hidden Markov Models for Human Genes

    DEFF Research Database (Denmark)

    Baldi, Pierre; Brunak, Søren; Chauvin, Yves

    1997-01-01

    We analyse the sequential structure of human genomic DNA by hidden Markov models. We apply models of widely different design: conventional left-right constructs and models with a built-in periodic architecture. The models are trained on segments of DNA sequences extracted such that they cover...

  1. Dermatologic hazards from hidden contacts with penicillin

    Energy Technology Data Exchange (ETDEWEB)

    Boonk, W.J.

    1981-01-01

    The unbridled use of penicillin after its discovery by Fleming has resulted in possible hazards to human health due to traces of the drug being present in food and other hidden sources. These hazards may include toxic effects, hypersensitivity reactions and possibly a raising of the frequency and duration of allergy to penicillin.

  2. The structural strength of glass: hidden damage

    NARCIS (Netherlands)

    Veer, F.A.; Rodichev, Y.M.

    2011-01-01

    We discuss “hidden damage” of glass by the rolling process, which results in heterogeneous distribution of microcracks on the edge surface of glass element, which are the fracture source deteriorating glass element strength. It is shown that removal of this damage on the edges of glass elements incr

  3. Computerized Testing: The Hidden Figures Test.

    Science.gov (United States)

    Jacobs, Ronald L.; And Others

    1985-01-01

    This study adapted the Hidden Figures Test for use on PLATO and determined the reliability of the computerized version compared to the paper and pencil version. Results indicate the test was successfully adapted with some modifications, and it was judged reliable although it may be measuring additional constructs. (MBR)

  4. Towards gauge unified, supersymmetric hidden strong dynamics

    CERN Document Server

    Chiang, Cheng-Wei; Ye, Fang

    2016-01-01

    We consider a class of models with extra complex scalars that are charged under both the Standard Model and a hidden strongly coupled $SU(N)_H$ gauge sector, and discuss the scenarios where the new scalars are identified as the messenger fields that mediate the spontaneously broken supersymmetries from the hidden sector to the visible sector. The new scalars are embedded into 5-plets and 10-plets of an $SU(5)_V$ gauge group that potentially unifies the Standard Model gauge groups. They also form a tower of bound states via hidden strong dynamics around the TeV scale. The Higgs bosons remain as elementary particles. Quadratically divergent contributions to the Higgs mass from the Standard Model fermions are canceled by the new scalar contributions to alleviate the fine-tuning problem. We also discuss a supersymmetrized version of this class of models, consisting of the minimal supersymmetric Standard Model plus extra chiral multiplets where the new scalars reside. Due to the hidden strong force, the new low-en...

  5. Hidden Costs and Challenges of Servitization

    DEFF Research Database (Denmark)

    Yang, Yifan; Slepniov, Dmitrij

    of these labels, the potential benefits of servitization are often overshadowed by costs associated with it. By using the cases of Chinese and Danish manufacturing firms, this study takes a closer look at possible hidden costs of servitization and contributes to our understanding of servitization performance...

  6. Policing of reproduction by hidden threats in a cooperative mammal.

    Science.gov (United States)

    Cant, Michael A; Nichols, Hazel J; Johnstone, Rufus A; Hodge, Sarah J

    2014-01-07

    The evolution of cooperation in animal and human societies is associated with mechanisms to suppress individual selfishness. In insect societies, queens and workers enforce cooperation by "policing" selfish reproduction by workers. Insect policing typically takes the form of damage limitation after individuals have carried out selfish acts (such as laying eggs). In contrast, human policing is based on the use of threats that deter individuals from acting selfishly in the first place, minimizing the need for damage limitation. Policing by threat could in principle be used to enforce reproductive suppression in animal societies, but testing this idea requires an experimental approach to simulate reproductive transgression and provoke out-of-equilibrium behavior. We carried out an experiment of this kind on a wild population of cooperatively breeding banded mongooses (Mungos mungo) in Uganda. In this species, each group contains multiple female breeders that give birth to a communal litter, usually on the same day. In a 7-y experiment we used contraceptive injections to manipulate the distribution of maternity within groups, triggering hidden threats of infanticide. Our data suggest that older, socially dominant females use the threat of infanticide to deter selfish reproduction by younger females, but that females can escape the threat of infanticide by synchronizing birth to the same day as older females. Our study shows that reproduction in animal societies can be profoundly influenced by threats that remain hidden until they are triggered experimentally. Coercion may thus extend well beyond the systems in which acts of infanticide are common.

  7. Boosted objects and jet substructure at the LHC. Report of BOOST2012, held at IFIC Valencia, 23rd-27th of July 2012

    Energy Technology Data Exchange (ETDEWEB)

    Altheimer, A.; Thompson, E.N. [Columbia University, Nevis Laboratory, Irvington, NY (United States); Arce, A.; Bjergaard, D. [Duke University, Durham, NC (United States); Asquith, L. [Argonne National Laboratory, Lemont, IL (United States); Backus Mayes, J.; Hook, A.; Izaguirre, E.; Jankowiak, M.; Larkoski, A.; Nef, P.; Schwartzman, A.; Swiatlowski, M.; Wacker, J. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Kuutmann, E.B. [Deutsches Elektronen-Synchrotron, DESY, Zeuthen (Germany); Humboldt University, Berlin (Germany); Berger, J. [Cornell University, Ithaca, NY (United States); Bryngemark, L. [Lund University, Lund (Sweden); Buckley, A.; Debenedetti, C. [University of Edinburgh, Edinburgh (United Kingdom); Butterworth, J.; Campanelli, M.; Davison, A. [University College London, London (United Kingdom); Cacciari, M. [CERN, Geneva 23 (Switzerland); Carli, T.; Roeck, A. de [LPTHE, UPMC Univ. Paris 6 et CNRS UMR, Paris (France); Chala, M. [CAFPE and Univ. of Granada, Granada (Spain); Chapleau, B. [McGill University, Montreal, QC (Canada); Chen, C. [Iowa State University, Ames, IA (United States); Chou, J.P. [Rutgers University, Piscataway, NJ (United States); Cornelissen, T.; Fleischmann, S. [Bergische Universitaet Wuppertal, Wuppertal (Germany); Curtin, D. [YITP, Stony Brook University, Stony Brook, NY (United States); Dasgupta, M. [University of Manchester, Manchester (United Kingdom); Almeida Dias, F. de [UNESP-Universidade Estadual Paulista, Sao Paulo (Brazil); De Cosa, A. [INFN, Naples (Italy); University of Naples, Naples (Italy); Doglioni, C.; Guescini, F. [University of Geneva, Geneva 4 (Switzerland); Ellis, S.D.; Hornig, A.; Scholtz, J. [University of Washington, Seattle, WA (United States); Fassi, F.; Hoz, S.G. de la; Kaci, M.; Oliver Garcia, E.; Rodrigo, G.; Salt, J.; Sanchez Martinez, V.; Villaplana, M.; Vos, M. [Instituto de Fisica Corpuscular, IFIC/CSIC-UVEG, Valencia (Spain); Ferrando, J.; Kar, D.; Nordstrom, K. [University of Glasgow, Glasgow (United Kingdom); Freytsis, M. [University of California, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); University of California, Berkeley, CA (United States); Gonzalez Silva, M.L. [Universidad de Buenos Aires, Buenos Aires (Argentina); Han, Z.; Lopez Mateos, D.; Schwartz, M.D. [Harvard University, Cambridge, MA (United States); Juknevich, J. [Weizmann Institute, Rehovot (Israel); Kasieczka, G.; Plehn, T.; Schaetzel, S.; Takeuchi, M. [Universitaet Heidelberg, Heidelberg (Germany); Kogler, R. [Universitaet Hamburg, Hamburg (Germany); Loch, P. [University of Arizona, Tucson, AZ (United States); Marzani, S.; Spannowsky, M. [IPPP, University of Durham, Durham (United Kingdom); Masetti, L. [Universitaet Mainz, Mainz (Germany); Mateu, V.; Stewart, I.; Thaler, J. [MIT, Cambridge, MA (United States); Miller, D.W. [University of Chicago, Chicago, IL (United States); Mishra, K.; Tran, N.V. [Fermi National Accelerator Laboratory, Batavia, IL (United States); Penwell, J. [Indiana University, Bloomington, IN (United States); Pilot, J. [University of California, Davis, CA (United States); Rappoccio, S. [Johns Hopkins University, Baltimore, MD (United States); University at Buffalo, State University of New York, Buffalo, NY (United States); Rizzi, A. [INFN, Pisa (Italy); University of Pisa, Pisa (Italy); Safonov, A. [Texas A and M University, College Station, TX (United States); Salam, G.P. [CERN, Geneva 23 (Switzerland); LPTHE, UPMC Univ. Paris 6 et CNRS UMR, Paris (France); Schioppa, M. [INFN, Rende (IT); University of Calabria, Rende (IT); Schmidt, A. [Universitaet Hamburg, Hamburg (DE); Universitaet Heidelberg, Heidelberg (DE); Segala, M. [Brown University, Richmond, RI (US); Son, M. [Yale University, New Haven, CT (US); Soyez, G. [CEA Saclay, Gif-sur-Yvette (FR); Strom, D. [University of Illinois, Chicago, IL (US); Vermilion, C. [University of California, Lawrence Berkeley National Laboratory, Berkeley, CA (US); Walsh, J. [University of California, Berkeley, CA (US)

    2014-03-15

    This report of the BOOST2012 workshop presents the results of four working groups that studied key aspects of jet substructure. We discuss the potential of first-principle QCD calculations to yield a precise description of the substructure of jets and study the accuracy of state-of-the-art Monte Carlo tools. Limitations of the experiments' ability to resolve substructure are evaluated, with a focus on the impact of additional (pile-up) proton proton collisions on jet substructure performance in future LHC operating scenarios. A final section summarizes the lessons learnt from jet substructure analyses in searches for new physics in the production of boosted top quarks. (orig.)

  8. Quantum Discord, CHSH Inequality and Hidden Variables -- Critical reassessment of hidden-variables models

    CERN Document Server

    Fujikawa, Kazuo

    2013-01-01

    Hidden-variables models are critically reassessed. It is first examined if the quantum discord is classically described by the hidden-variable model of Bell in the Hilbert space with $d=2$. The criterion of vanishing quantum discord is related to the notion of reduction and, surprisingly, the hidden-variable model in $d=2$, which has been believed to be consistent so far, is in fact inconsistent and excluded by the analysis of conditional measurement and reduction. The description of the full contents of quantum discord by the deterministic hidden-variables models is not possible. We also re-examine CHSH inequality. It is shown that the well-known prediction of CHSH inequality $|B|\\leq 2$ for the CHSH operator $B$ introduced by Cirel'son is not unique. This non-uniqueness arises from the failure of linearity condition in the non-contextual hidden-variables model in $d=4$ used by Bell and CHSH, in agreement with Gleason's theorem which excludes $d=4$ non-contextual hidden-variables models. If one imposes the l...

  9. Online mixted sampling: An application in hidden populations

    Directory of Open Access Journals (Sweden)

    Fabiola Baltar

    2012-04-01

    Full Text Available Objeto: El objetivo de este artículo es explorar las posibilidades que ofrecen las nuevas tecnologías de información y la aparición de las redes sociales virtuales, para el reclutamiento de unidades muestrales en poblaciones ocultas y como soporte del uso de métodos mixtos.Diseño/metodología/enfoque: El objetivo era identificar a los empresarios argentinos que iniciaron negocios en España. Esta unidad de observación, presenta características que la definen como población oculta: 1 elevada dispersión geográfica que dificulta su localización; 2 subestimación en el número de argentinos residentes en las estadísticas oficiales; 3 argentinos residentes en situación ilegal; y, 4 en muchos casos los factores que motivaron la emigración son negativos, por lo que genera reticencia a contestar. En este contexto, se desarrolló (1 el muestreo virtual online y (2 el muestreo por bola de nieve tradicional. En el muestreo virtual online se utilizó la red social Facebook, mediante la cual se identificaron 52 grupos virtuales que nuclean a argentinos que viven en España. Posteriormente, se envío a cada miembro un mensaje personal explicando el propósito del estudio e invitándolos a participar en el mismo.Aportaciones y resultados: A través de la realización del estudio, se comprueba que mediante el uso de redes sociales es posible acceder a unidades de observación que no se hubieran detectado por vías institucionales (registros administrativos, censos, etc.. Este resultado demuestra que este tipo de herramientas, contribuyen a incrementar el alcance geográfico y el tamaño de la muestra, favorecen al diseño de la muestra cualitativa y la triangulación de resultados, aumentando la validez de los estudios de poblaciones ocultas.Originalidad / Valor añadido: El artículo presenta una experiencia de aplicación de muestreo virtual y métodos mixtos en el estudio de poblaciones ocultas, a partir del análisis del empresariado inmigrante argentino y utilizando como fuentes de información los grupos virtuales.

  10. Factorization for groomed jet substructure beyond the next-to-leading logarithm

    CERN Document Server

    Frye, Christopher; Schwartz, Matthew D; Yan, Kai

    2016-01-01

    Jet grooming algorithms are widely used in experimental analyses at hadron colliders to remove contaminating radiation from within jets. While the algorithms perform a great service to the experiments, their intricate algorithmic structure and multiple parameters has frustrated precision theoretic understanding. In this paper, we demonstrate that one particular groomer called soft drop actually makes precision jet substructure easier. In particular, we derive a factorization formula for a large class of soft drop jet substructure observables, including jet mass. The essential observation that allows for this factorization is that, without the soft wide-angle radiation groomed by soft drop, all singular contributions are collinear. The simplicity and universality of the collinear limit in QCD allows us to show that to all orders, the normalized differential cross section has no contributions from non-global logarithms. It is also independent of process, up to the relative fraction of quark and gluon jets. In f...

  11. Prefabricated floor panels composed of fiber reinforced concrete and a steel substructure

    DEFF Research Database (Denmark)

    Lárusson, Lárus H.; Fischer, Gregor; Jönsson, Jeppe

    2013-01-01

    loading at the serviceability and ultimate limit states. The composite construction concept offers flexibility in the assembly process, the ability to adapt to various load and boundary requirements, and efficient utilization of material properties that result in a light weight prefabricated structural......This paper reports on a study on prefabricated composite and modular floor deck panels composed of relatively thin fiber reinforced concrete slabs connected to steel substructures. The study focuses on the design, manufacturing, structural improvements and behavior of the floor systems during...... detailing of these integrally cast deck panels and to modify them by providing individually cast anchor points in the precast ECC slab, which are subsequently used to attach a steel truss substructure.Full-scale experiments were carried out to verify the structural behavior of the integrally cast panels...

  12. Performance of large-R jets and jet substructure reconstruction with the ATLAS detector

    CERN Document Server

    The ATLAS collaboration

    2012-01-01

    This paper presents the application of techniques to study jet substructure. The performance of modified jet algorithms for a variety of jet types and event topologies is investigated. Properties of jets subjected to the mass-drop filtering, trimming and pruning algorithms are found to have a reduced sensitivity to multiple proton-proton interactions and exhibit improved stability at high luminosity. Monte Carlo studies of the signal-background discrimination with jet grooming in new physics searches based on jet invariant mass and jet substructure properties are also presented. The application of jet trimming is shown to improve the robustness of large-R jet measurements, reduce sensitivity to the superfluous effects due to the intense environment of the high luminosity LHC, and improve the physics potential of searches for heavy boosted objects. The analyses presented in this note use the full 2011 ATLAS dataset, corresponding to an integrated luminosity of 4.7 \\pm 0.2 fb−1 .

  13. Development and Demonstration of a Magnesium-Intensive Vehicle Front-End Substructure

    Energy Technology Data Exchange (ETDEWEB)

    Logan, Stephen D. [United States Automotive Materials Partnership LLC, Southfield, MI (United States); Forsmark, Joy H. [United States Automotive Materials Partnership LLC, Southfield, MI (United States); Osborne, Richard [United States Automotive Materials Partnership LLC, Southfield, MI (United States)

    2016-07-01

    This project is the final phase (designated Phase III) of an extensive, nine-year effort with the objectives of developing a knowledge base and enabling technologies for the design, fabrication and performance evaluation of magnesium-intensive automotive front-end substructures intended to partially or completely replace all-steel comparators, providing a weight savings approaching 50% of the baseline. Benefits of extensive vehicle weight reduction in terms of fuel economy increase, extended vehicle range, vehicle performance and commensurate reductions in greenhouse gas emissions are well known. An exemplary vehicle substructure considered by the project is illustrated in Figure 1, along with the exterior vehicle appearance. This unibody front-end “substructure” is one physical objective of the ultimate design and engineering aspects established at the outset of the larger collective effort.

  14. Damage detection test of a substructure model of the National Swimming Center

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to detect the damage locations of complex spatial structures, a sensor region-based damage detection approach was developed based on the damage locating vectors method. A normalized damage locating index was introduced to identify the damage regions. An experiment on damage detection of a substructure model of the National Swimming Center ’Water Cube’ was carried out. Two damage patterns were involved in the experiment. The test model was excited by using hammer impacts. Acceleration responses of the undamaged and damaged structure model were measured. Modal parameters were identified from the acceleration responses by utilizing the eigensystem realization algorithm (ERA). By using the developed sensor region-based method, the damage regions of the substructure model were located. The results show that the proposed method is able to effec- tively locate the damage regions.

  15. Fast and accurate protein substructure searching with simulated annealing and GPUs

    Directory of Open Access Journals (Sweden)

    Stivala Alex D

    2010-09-01

    Full Text Available Abstract Background Searching a database of protein structures for matches to a query structure, or occurrences of a structural motif, is an important task in structural biology and bioinformatics. While there are many existing methods for structural similarity searching, faster and more accurate approaches are still required, and few current methods are capable of substructure (motif searching. Results We developed an improved heuristic for tableau-based protein structure and substructure searching using simulated annealing, that is as fast or faster and comparable in accuracy, with some widely used existing methods. Furthermore, we created a parallel implementation on a modern graphics processing unit (GPU. Conclusions The GPU implementation achieves up to 34 times speedup over the CPU implementation of tableau-based structure search with simulated annealing, making it one of the fastest available methods. To the best of our knowledge, this is the first application of a GPU to the protein structural search problem.

  16. New Constraints on the Complex Mass Substructure in Abell 1689 from Gravitational Flexion

    CERN Document Server

    Leonard, Adrienne; Goldberg, David M

    2010-01-01

    In a recent publication, the flexion aperture mass statistic was found to provide a robust and effective method by which substructure in galaxy clusters might be mapped. Moreover, we suggested that constraints on the masses and mass profile of structures might be constrained using this method. In this paper, we apply the flexion aperture mass technique to HST ACS images of Abell 1689. We compare this measure to the weak lensing shear aperture mass statistic, and demonstrate that the flexion aperture mass statistic is more sensitive to structures on the scales considered, dramatically outperforming the shear aperture mass statistic on this dataset, which suffers from persistent systematic noise. While the central potential is not constrained by our method, due largely to missing data in the central 0.5$^\\prime$ of the cluster, we are able to place constraints on the masses and mass profiles of prominent substructures. Considering 16 flexion aperture mass reconstructions, we identify 4 separate mass peaks, and ...

  17. Twisting phonons in complex crystals with quasi-one-dimensional substructures.

    Science.gov (United States)

    Chen, Xi; Weathers, Annie; Carrete, Jesús; Mukhopadhyay, Saikat; Delaire, Olivier; Stewart, Derek A; Mingo, Natalio; Girard, Steven N; Ma, Jie; Abernathy, Douglas L; Yan, Jiaqiang; Sheshka, Raman; Sellan, Daniel P; Meng, Fei; Jin, Song; Zhou, Jianshi; Shi, Li

    2015-04-15

    A variety of crystals contain quasi-one-dimensional substructures, which yield distinctive electronic, spintronic, optical and thermoelectric properties. There is a lack of understanding of the lattice dynamics that influences the properties of such complex crystals. Here we employ inelastic neutron scatting measurements and density functional theory calculations to show that numerous low-energy optical vibrational modes exist in higher manganese silicides, an example of such crystals. These optical modes, including unusually low-frequency twisting motions of the Si ladders inside the Mn chimneys, provide a large phase space for scattering acoustic phonons. A hybrid phonon and diffuson model is proposed to explain the low and anisotropic thermal conductivity of higher manganese silicides and to evaluate nanostructuring as an approach to further suppress the thermal conductivity and enhance the thermoelectric energy conversion efficiency. This discovery offers new insights into the structure-property relationships of a broad class of materials with quasi-one-dimensional substructures for various applications.

  18. Characterization Method for 3D Substructure of Nuclear Cell Based on Orthogonal Phase Images

    Directory of Open Access Journals (Sweden)

    Ying Ji

    2015-01-01

    Full Text Available A set of optical models associated with blood cells are introduced in this paper. All of these models are made up of different parts possessing symmetries. The wrapped phase images as well as the unwrapped ones from two orthogonal directions related to some of these models are obtained by simulation technique. Because the phase mutation occurs on the boundary between nucleus and cytoplasm as well as on the boundary between cytoplasm and environment medium, the equation of inflexion curve is introduced to describe the size, morphology, and substructure of the nuclear cell based on the analysis of the phase features of the model. Furthermore, a mononuclear cell model is discussed as an example to verify this method. The simulation result shows that characterization with inflexion curve based on orthogonal phase images could describe the substructure of the cells availably, which may provide a new way to identify the typical biological cells quickly without scanning.

  19. A substructure inside spiral arms, and a mirror image across the Galactic Meridian

    CERN Document Server

    Vallee, Jacques P

    2016-01-01

    While the galactic density wave theory is over 50 years old and well known in science, whether it fits our own Milky Way disk has been difficult to say. Here we show a substructure inside the spiral arms. This substructure is reversing with respect to the Galactic Meridian (longitude zero), and crosscuts of the arms at negative longitudes appear as mirror images of crosscuts of the arms at positive longitudes. Four lanes are delineated: mid-arm (extended 12CO gas at mid arm, HI atoms), in-between offset by about 100 pc (synchrotron, radio recombination lines), in between offset by about 200 pc (masers, colder dust), and inner edge (hotter dust seen in Mid-IR and Near-IR).

  20. Seasonal variations of radon concentrations in single-family houses with different sub-structures

    DEFF Research Database (Denmark)

    Majborn, B.

    1992-01-01

    Seasonal variations of indoor radon concentrations have been studied in 70 single-family houses selected according to the type of sub-structure and the type of soil underneath the house. Five categories of sub-structure were included - slab-on-grade, crawl space, basement, and combinations...... of basement with slab-on-grade or crawl space. Half of the houses are located on clayey till and the other half on glaciofluvial gravel. In each house radon was measured in a living room and a bedroom, in the basement if present, and in the crawl space if present and accessible. The measurements were made...... with track detectors on a quarterly basis throughout a year. For living rooms and bedrooms the seasonal variations range from being highly significant for the slab-on-grade houses to being insignificant for the crawl space houses. For basements and crawl spaces the geometric mean radon concentrations do...

  1. Ring and jet study on the azimuthal substructure of pions at CERN SPS energy

    Indian Academy of Sciences (India)

    Prabir Kumar Haldar; Sanjib Kumar Manna; Prosenjit Saha; Dipak Ghosh

    2013-04-01

    We have presented an investigation on the ring- and jet-like azimuthal angle sub-structures in the emission of secondary charged hadrons coming from 32S–Ag/Br interactions at 200 A GeV/c. Nuclear photographic emulsion technique has been employed to collect the experimental data. The presence of such substructures, their average behaviour, their size, and their position of occurrence have been examined. The experimental results have also been compared with the results simulated by Monte-Carlo method. The analysis strongly indicates the presence of ring- and jet-like structures in the experimental distributions of particles beyond statistical noise. The experimental results are in good agreement with I M Dremin idea, that the phenomenon is similar to the emission of Cherenkov electromagnetic radiation.

  2. Damage detection test of a substructure model of the National Swimming Center

    Institute of Scientific and Technical Information of China (English)

    QIAN JiaRu; JI XiaoDong; ZHANG WeiJing; XU LongHe; FU XueYi; GU Lei

    2008-01-01

    In order to detect the damage locations of complex spatial structures,a sensor region-based damage detection approach was developed based on the damage locating vectors method.A normalized damage locating index was introduced to identify the damage regions.An experiment on damage detection of a substructure model of the National Swimming Center 'Water Cube' was carried out.Two damage patterns were involved in the experiment.The test model was excited by using hammer impacts.Acceleration responses of the undamaged and damaged struc-ture model were measured.Modal parameters were identified from the acceleration responses by utilizing the eigensystem realization algorithm (ERA).By using the developed sensor region-based method,the damage regions of the substructure model were located.The results show that the proposed method is able to effec-tively locate the damage regions.

  3. Substructure of Crystalline Peroxisomes in Methanol-Grown Hansenula polymorpha : Evidence for an In Vivo Crystal of Alcohol Oxidase

    NARCIS (Netherlands)

    Veenhuis, Marten; Harder, Wim; Dijken, Johannes P. van; Mayer, Frank

    1981-01-01

    The substructural organization of completely crystalline peroxisomes present in Hansenula polymorpha cells grown under methanol limitation in a chemostat was investigated by different cytochemical and ultrastructural techniques. Time-dependent cytochemical staining experiments indicated that activit

  4. AFM friction and adhesion mapping of the substructures of human hair cuticles

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James R., E-mail: james.smith@port.ac.uk [School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael' s Building, White Swan Road, Portsmouth, PO1 2DT (United Kingdom); Tsibouklis, John; Nevell, Thomas G. [School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael' s Building, White Swan Road, Portsmouth, PO1 2DT (United Kingdom); Breakspear, Steven [School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael' s Building, White Swan Road, Portsmouth, PO1 2DT (United Kingdom); Global R and D–Hair Beauty Laboratory, Kao Corporation, 2-1-3, Bunka Sumida-ku, Tokyo, 131-8501 (Japan)

    2013-11-15

    Using atomic force microscopy, values of the microscale friction coefficient, the tip (silicon nitride) - surface adhesion force and the corresponding adhesion energy, for the substructures that constitute the surface of human hair (European brown hair) have been determined from Amonton plots. The values, mapped for comparison with surface topography, corresponded qualitatively with the substructures’ plane surface characteristics. Localised maps and values of the frictional coefficient, extracted avoiding scale edge effects, are likely to inform the formulation of hair-care products and treatments.

  5. Substructures developed during creep and cyclic tests of type 304 stainless steel (heat 9T2796)

    Energy Technology Data Exchange (ETDEWEB)

    Swindeman, R.W.; Bhargava, R.K.; Sikka, V.K.; Moteff, J.

    1977-09-01

    Substructures developed in tested specimens of a reference heat of type 304 stainless steel (heat 9T2796) are examined. Data include dislocation densities, cell and subgrain sizes, and carbide precipitate sizes. Testing conditions range for temperatures from 482 to 649/sup 0/C, for stresses from 28 to 241 MPa, and for times from 4 to 15,000 hr. As expected, it is observed that temperature, stress, and time have strong influences on substructure. The change in the dislocation density is too small to measure for conditions which produce less than 1 percent monotonic strain. No cells form, and the major alteration of substructure is the precipitation of M/sub 23/C/sub 6/ carbides on grain boundaries, on twin boundaries, and on some dislocations. At stresses ranging from 69 to 172 MPa and at temperatures ranging from 482 to 593/sup 0/C, the dislocation density increases with increasing stress and is generally higher than expected from studies made at higher temperatures. Dislocations are arranged in fine networks stabilized by carbides. At stresses above 172 MPa and temperatures to 649/sup 0/C, the dislocation density is too great to measure. Cells develop which are finer in size than cells developed at similar stresses but at higher temperatures. Dislocation densities and cell sizes for cyclic specimens are comparable to data for creep-tested specimens. On the basis of the observed substructures, recommendations are made regarding further studies which would assist in the development of constitutive equations for high-temperature inelastic analysis of reactor components.

  6. Substructuring preconditioners for an h-p domain decomposition method with interior penalty mortaring

    KAUST Repository

    Antonietti, P. F.

    2014-05-13

    We propose and study an iterative substructuring method for an h-p Nitsche-type discretization, following the original approach introduced in Bramble et al. Math. Comp. 47(175):103–134, (1986) for conforming methods. We prove quasi-optimality with respect to the mesh size and the polynomial degree for the proposed preconditioner. Numerical experiments assess the performance of the preconditioner and verify the theory. © 2014, Springer-Verlag Italia.

  7. Pre-Processing and Re-Weighting Jet Images with Different Substructure Variables

    CERN Document Server

    Huynh, Lynn

    2016-01-01

    This work is an extension of Monte Carlo simulation based studies in tagging boosted, hadronically decaying W bosons at a center of mass energy of s = 13 TeV. Two pre-processing techniques used with jet images, translation and rotation, are first examined. The generated jet images for W signal jets and QCD background jets are then rescaled and weighted with five different substructure variables for visual comparison.

  8. A dynamic model with substructures for contact-impact analysis of flexible multibody systems

    Institute of Scientific and Technical Information of China (English)

    GUO; Anping(郭安萍); HONG; Jiazhen(洪嘉振); YANG; Hui(杨辉)

    2003-01-01

    Using a substructure synthesis method this paper studies the longitudinal compressive impact of a flexible bar with a rigid body. The crucial variable affecting the validity of the method is derived theoretically. By computational simulation tests, excellent agreement has been found between the solution of this model and the exact solution when the variable is chosen suitably. Considering both the computational efficiency and the accuracy of solutions obtained on the model in different engineering problems, several optimum values of the variable are suggested.

  9. Thinking outside the ROCs: Designing Decorrelated Taggers (DDT) for jet substructure

    Science.gov (United States)

    Dolen, James; Harris, Philip; Marzani, Simone; Rappoccio, Salvatore; Tran, Nhan

    2016-05-01

    We explore the scale-dependence and correlations of jet substructure observables to improve upon existing techniques in the identification of highly Lorentz-boosted objects. Modified observables are designed to remove correlations from existing theoretically well-understood observables, providing practical advantages for experimental measurements and searches for new phenomena. We study such observables in W jet tagging and provide recommendations for observables based on considerations beyond signal and background efficiencies.

  10. Thinking outside the ROCs: Designing Decorrelated Taggers (DDT) for jet substructure

    CERN Document Server

    Dolen, James; Marzani, Simone; Rappoccio, Salvatore; Tran, Nhan

    2016-01-01

    We explore the scale-dependence and correlations of jet substructure observables to improve upon existing techniques in the identification of highly Lorentz-boosted objects. Modified observables are designed to remove correlations from existing theoretically well-understood observables, providing practical advantages for experimental measurements and searches for new phenomena. We study such observables in $W$ jet tagging and provide recommendations for observables based on considerations beyond signal and background efficiencies.

  11. Aligned Carbon Nanotube Reinforcement of Aerospace Carbon Fiber Composites: Substructural Strength Evaluation for Aerostructure Applications

    OpenAIRE

    Guzman de Villoria, Roberto; Ydrefors, L.; Hallander, P.; Ishiguro, Kyoko; Nordin, P.; Wardle, Brian L.

    2012-01-01

    Vertically aligned carbon nanotubes (VACNTs) are placed between all plies in an aerospace carbon fiber reinforced plastic laminate (unidirectional plies, [(0/90/±45)2]s) to reinforce the interlaminar region in the z-direction. Significant improvement in Mode I and II interlaminar toughness have been observed previously. In this work, several substructural in-plane strength tests relevant to aerostructures were undertaken: bolt/tension-bearing, open hole compression, and L-shape laminate be...

  12. Substructure Analysis of Selected Low Richness 2dFGRS Clusters of Galaxies

    CERN Document Server

    Burgett, W S; Davis, D S; Colless, M; De Propris, R; Baldry, I K; Baugh, C; Bland-Hawthorn, J; Bridges, T J; Cannon, R; Cole, S; Collins, C; Couch, W; Cross, N; Dalton, G B; Driver, S; Efstathiou, G P; Ellis, R; Frenk, C; Glazebrook, K; Hawkins, E; Jackson, C; Lahav, O; Lewis, I; Lumsden, S; Maddox, S; Madgwick, D; Norberg, P; Peacock, J A; Percival, W; Peterson, B; Sutherland, W; Taylor, K; Burgett, William S.; Vick, Michael M.; Davis, David S.; Colless, Matthew; Propris, Roberto De; Baldry, Ivan; Baugh, Carlton; Bland-Hawthorn, Joss; Bridges, Terry; Cannon, Russell; Cole, Shaun; Collins, Chris; Couch, Warrick; Cross, Nicholas; Dalton, Gavin; Driver, Simon; Efstathiou, George; Ellis, Richard; Frenk, Carlos; Glazebrook, Karl; Hawkins, Edward; Jackson, Carole; Lahav, Ofer; Lewis, Ian; Lumsden, Stuart; Maddox, Steve; Madgwick, Darren; Norberg, Peder; Peacock, John A.; Percival, Will; Peterson, Bruce; Sutherland, Will; Taylor, Keith

    2004-01-01

    Complementary one-, two-, and three-dimensional tests for detecting the presence of substructure in clusters of galaxies are applied to recently obtained data from the 2dF Galaxy Redshift Survey. The sample of 25 clusters used in this study includes 16 clusters not previously investigated for substructure. Substructure is detected at or greater than the 99% CL level in at least one test for 21 of the 25 clusters studied here. From the results, it appears that low richness clusters commonly contain subclusters participating in mergers. About half of the clusters have two or more components within 0.5 h^{-1} Mpc of the cluster centroid, and at least three clusters (Abell 1139, Abell 1663, and Abell S333) exhibit velocity-position characteristics consistent with the presence of possible cluster rotation, shear, or infall dynamics. The geometry of certain features is consistent with influence by the host supercluster environments. In general, our results support the hypothesis that low richness clusters relax to ...

  13. Dynamic substructure model for multiple impact responses of micro/nano piezoelectric precision drive system

    Institute of Scientific and Technical Information of China (English)

    SHEN YuNian; YIN XiaoChun

    2009-01-01

    A dynamic substructure technique which considers the electromechanlcal coupling effect of the PZT and the inertial effect of flexible components is presented to study the multiple impact dynamic be-havior of micro/nano piezoelectric impact drive systems. It can investigate the step-like motion of ob-ject body and the multiple impacts behaviors reasonably by the comparison of the experimental data and the numerical solution of the spring-mass model. It is expected to have higher accuracy in the numerical simulations of the motion and the responses, especially to high frequency pulse voltage excitations. The present dynamic substructure technique has firstly studied reasonably the propaga-tions of piezoelectric-induced transient waves and impact-induced transient waves. It is helpful to the failure analysis and the design of piezoelectric stack and flexible components. The present dynamic substructure technique can be applied to the transient dynamics optimization design and the precision control of the micro/nano piezoelectric impact drive systems.

  14. Indirect Inverse Substructuring Method for Multibody Product Transport System with Rigid and Flexible Coupling

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2015-01-01

    Full Text Available The aim of this paper is to develop a new frequency response function- (FRF- based indirect inverse substructuring method without measuring system-level FRFs in the coupling DOFs for the analysis of the dynamic characteristics of a three-substructure coupled product transport system with rigid and flexible coupling. By enforcing the dynamic equilibrium conditions at the coupling coordinates and the displacement compatibility conditions, a closed-form analytical solution to inverse substructuring analysis of multisubstructure coupled product transport system is derived based on the relationship of easy-to-monitor component-level FRFs and the system-level FRFs at the coupling coordinates. The proposed method is validated by a lumped mass-spring-damper model, and the predicted coupling dynamic stiffness is compared with the direct computation, showing exact agreement. The method developed offers an approach to predict the unknown coupling dynamic stiffness from measured FRFs purely. The suggested method may help to obtain the main controlling factors and contributions from the various structure-borne paths for product transport system.

  15. Automatic identification of mobile and rigid substructures in molecular dynamics simulations and fractional structural fluctuation analysis.

    Directory of Open Access Journals (Sweden)

    Leandro Martínez

    Full Text Available The analysis of structural mobility in molecular dynamics plays a key role in data interpretation, particularly in the simulation of biomolecules. The most common mobility measures computed from simulations are the Root Mean Square Deviation (RMSD and Root Mean Square Fluctuations (RMSF of the structures. These are computed after the alignment of atomic coordinates in each trajectory step to a reference structure. This rigid-body alignment is not robust, in the sense that if a small portion of the structure is highly mobile, the RMSD and RMSF increase for all atoms, resulting possibly in poor quantification of the structural fluctuations and, often, to overlooking important fluctuations associated to biological function. The motivation of this work is to provide a robust measure of structural mobility that is practical, and easy to interpret. We propose a Low-Order-Value-Optimization (LOVO strategy for the robust alignment of the least mobile substructures in a simulation. These substructures are automatically identified by the method. The algorithm consists of the iterative superposition of the fraction of structure displaying the smallest displacements. Therefore, the least mobile substructures are identified, providing a clearer picture of the overall structural fluctuations. Examples are given to illustrate the interpretative advantages of this strategy. The software for performing the alignments was named MDLovoFit and it is available as free-software at: http://leandro.iqm.unicamp.br/mdlovofit.

  16. Major Substructure in the M31 Outer Halo: the East Cloud

    CERN Document Server

    McMonigal, B; Conn, A R; Mackey, A D; Lewis, G F; Irwin, M J; Martin, N F; McConnachie, A W; Ferguson, A M N; Ibata, R A; Huxor, A P

    2015-01-01

    We present the first detailed analysis of the East Cloud, a highly disrupted diffuse stellar substructure in the outer halo of M31. The core of the substructure lies at a projected distance of $\\sim100$ kpc from the centre of M31 in the outer halo, with possible extensions reaching right into the inner halo. Using Pan-Andromeda Archaeological Survey photometry of red giant branch stars, we measure the distance, metallicity and brightness of the cloud. Using Hubble Space Telescope data, we independently measure the distance and metallicity to the two globular clusters coincident with the East Cloud core, PA-57 and PA-58, and find their distances to be consistent with the cloud. Four further globular clusters coincident with the substructure extensions are identified as potentially associated. Combining the analyses, we determine a distance to the cloud of $814^{+20}_{-9}$ kpc, a metallicity of $[Fe/H] = -1.2\\pm0.1$, and a brightness of $M_V = -10.7\\pm0.4$ mag. Even allowing for the inclusion of the potential e...

  17. Dynamic substructure model for multiple impact responses of micro/nano piezoelectric precision drive system

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A dynamic substructure technique which considers the electromechanical coupling effect of the PZT and the inertial effect of flexible components is presented to study the multiple impact dynamic be- havior of micro/nano piezoelectric impact drive systems. It can investigate the step-like motion of ob- ject body and the multiple impacts behaviors reasonably by the comparison of the experimental data and the numerical solution of the spring-mass model. It is expected to have higher accuracy in the numerical simulations of the motion and the responses, especially to high frequency pulse voltage excitations. The present dynamic substructure technique has firstly studied reasonably the propaga- tions of piezoelectric-induced transient waves and impact-induced transient waves. It is helpful to the failure analysis and the design of piezoelectric stack and flexible components. The present dynamic substructure technique can be applied to the transient dynamics optimization design and the precision control of the micro/nano piezoelectric impact drive systems.

  18. A hybrid system identification methodology for wireless structural health monitoring systems based on dynamic substructuring

    Science.gov (United States)

    Dragos, Kosmas; Smarsly, Kay

    2016-04-01

    System identification has been employed in numerous structural health monitoring (SHM) applications. Traditional system identification methods usually rely on centralized processing of structural response data to extract information on structural parameters. However, in wireless SHM systems the centralized processing of structural response data introduces a significant communication bottleneck. Exploiting the merits of decentralization and on-board processing power of wireless SHM systems, many system identification methods have been successfully implemented in wireless sensor networks. While several system identification approaches for wireless SHM systems have been proposed, little attention has been paid to obtaining information on the physical parameters (e.g. stiffness, damping) of the monitored structure. This paper presents a hybrid system identification methodology suitable for wireless sensor networks based on the principles of component mode synthesis (dynamic substructuring). A numerical model of the monitored structure is embedded into the wireless sensor nodes in a distributed manner, i.e. the entire model is segmented into sub-models, each embedded into one sensor node corresponding to the substructure the sensor node is assigned to. The parameters of each sub-model are estimated by extracting local mode shapes and by applying the equations of the Craig-Bampton method on dynamic substructuring. The proposed methodology is validated in a laboratory test conducted on a four-story frame structure to demonstrate the ability of the methodology to yield accurate estimates of stiffness parameters. Finally, the test results are discussed and an outlook on future research directions is provided.

  19. Spectroscopy of Bright QUEST RR Lyrae Stars: Velocity Substructures toward Virgo

    CERN Document Server

    Vivas, A Katherina; Zinn, Robert; Winnick, Rebeccah; Duffau, Sonia; Mateu, Cecilia

    2008-01-01

    Using a sample of 43 bright (V<16.1, distance <13 kpc) RR Lyrae stars (RRLS) from the QUEST survey with spectroscopic radial velocities and metallicities, we find that several separate halo substructures contribute to the Virgo overdensity (VOD). While there is little evidence for halo substructure in the spatial distribution of these stars, their distribution in radial velocity reveals two moving groups. These results are reinforced when the sample is combined with a sample of blue horizontal branch stars that were identified in the SDSS, and the combined sample provides evidence for one additional moving group. These groups correspond to peaks in the radial velocity distribution of a sample of F type main-sequence stars that was recently observed in the same directon by SEGUE, although in one case the RRLS and F star groups may not lie at the same distance. One of the new substructures has a very narrow range in metallicity, which is more consistent with it being the debris from a destroyed globular c...

  20. Atomic force microscopic observation on substructure of pollen exine in Cedrus deodara and Metasequoia glyptostroboides

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The substructure of pollen exine in Cedrus deodara (Roxb.) Loud. and Metasequoia glyptostroboides Hu et Cheng has been examined with an atomic force microscope (AFM). The results indicate that the exine substructure units containing sporopollenin in two species are similar in shape, which are granular, but slightly different in size. In Cedrus the substructure unit of pollen exine appears to be 56-99 nm long and 42-74 nm wide, while in Metasequoia it appears to be 81-118 nm long and 43-98 nm wide. It has been observed that the subunits of pollen exine in Cedrus arranged tightly to form short-rod-like or spheroidal pollen exine units, several or more than ten of which formed an island-like structure. There are various spaces among these island-like structures which are interconnected to occupy the entire pollen exine. In Metasequoia, the subunits of pollen exine also arranged tightly with a distribution tendency of cluster of 3-10, however, no obvious boundary exists among these clusters. From our results, it is concluded that there is no tendency of helical arrangement for the subunits of pollen exine in Cedrus and Metasequoia, and the results support Southworth' view that subunits of pollen exine are granular shape in lattice structure.

  1. Are pulsars born with a hidden magnetic field?

    CERN Document Server

    Torres-Forné, Alejandro; Pons, José A; Font, José A

    2015-01-01

    The observation of several neutron stars in the center of supernova remnants and with significantly lower values of the dipolar magnetic field than the average radio-pulsar population has motivated a lively debate about their formation and origin, with controversial interpretations. A possible explanation requires the slow rotation of the proto-neutron star at birth, which is unable to amplify its magnetic field to typical pulsar levels. An alternative possibility, the hidden magnetic field scenario, considers the accretion of the fallback of the supernova debris onto the neutron star as responsible for the submergence (or screening) of the field and its apparently low value. In this paper we study under which conditions the magnetic field of a neutron star can be buried into the crust due to an accreting, conducting fluid. For this purpose, we consider a spherically symmetric calculation in general relativity to estimate the balance between the incoming accretion flow and the magnetosphere. Our study analyse...

  2. Calibration of TDR Test Probe for Measuring Moisture in the Body of the Railway Substructure and its Subgrade

    Directory of Open Access Journals (Sweden)

    Dobeš Peter

    2015-12-01

    Full Text Available In the introduction of the paper there is characterized a way of monitoring the moisture in the railway substructure in the experimental stand, which is a part of the experimental workplace of the Department of Railway Engineering and Track Management. A substantial part of the paper is devoted to the calibration of TDR test probe for selected rock materials as a basic prerequisite for the determination of the actual moisture in the body of the railway substructure and subgrade.

  3. Hidden penis release: adjunctive suprapubic lipectomy.

    Science.gov (United States)

    Horton, C E; Vorstman, B; Teasley, D; Winslow, B

    1987-08-01

    We believe the hidden penis may be caused and concealed by a prominent suprapubic fat pad in addition to the restrictive fibrous bands of the dartos fascia fixing the shaft of the penis proximally while loose skin folds prolapse distally over the phallus. A penis of inadequate length or appearance may affect body image. Patients with this problem often require psychological support. Hidden penis may be distinguished from micropenis by palpating adequate corpora and showing a stretched penile length within 2 SD of normal. Excision of suprapubic fat with sectioning of the tethering dartos bands will release and increase the length of the penis. Suprapubic fat pad resection may also be helpful to elongate a short penis in cases of adult microphallus, or after partial penectomy because of trauma or cancer. Circumcision is contraindicated.

  4. Laser experiments explore the hidden sector

    CERN Document Server

    Ahlers, M; Jaeckel, J; Redondo, J; Ringwald, A

    2007-01-01

    Recently, the laser experiments BMV and GammeV, searching for light shining through walls, have published data and calculated new limits on the allowed masses and couplings for axion-like particles. In this note we point out that these experiments can serve to constrain a much wider variety of hidden-sector particles such as, e.g., minicharged particles and hidden-sector photons. The new experiments improve the existing bounds from the older BFRT experiment by a factor of two. Moreover, we use the new PVLAS constraints on a possible rotation and ellipticity of light after it has passed through a strong magnetic field to constrain pure minicharged particle models. For masses <~0.05 eV, the charge is now restricted to be less than (3-4)x10^(-7) times the electron electric charge. This is the best laboratory bound and comparable to bounds inferred from the energy spectrum of the cosmic microwave background.

  5. Extended abstract of a hidden agenda

    Energy Technology Data Exchange (ETDEWEB)

    Goguen, J.; Malcolm, G. [Oxford Univ. (United Kingdom)

    1996-12-31

    The initial goal of our hidden research programme was both straightforward and ambitious: give a semantics for software engineering, and in particular for the object paradigm, supporting correctness proofs that are as simple and mechanical as possible. This emphasizes proofs rather than models, and thus suggests an equational approach, rather than one based on higher order logic, denotational semantics, or any kind of model, because equational proofs achieve maximal simplicity and mechanization, and yet are fully expressive. We introduce powerful coinduction techniques for proving behavioral properties of complex systems. We make the no doubt outrageous claim that our hidden approach gives simpler proofs than other formalisms; this is because we exploit algebraic structure that most other approaches discard.

  6. Hidden geometric correlations in real multiplex networks

    Science.gov (United States)

    Kleineberg, Kaj-Kolja; Boguñá, Marián; Ángeles Serrano, M.; Papadopoulos, Fragkiskos

    2016-11-01

    Real networks often form interacting parts of larger and more complex systems. Examples can be found in different domains, ranging from the Internet to structural and functional brain networks. Here, we show that these multiplex systems are not random combinations of single network layers. Instead, they are organized in specific ways dictated by hidden geometric correlations between the layers. We find that these correlations are significant in different real multiplexes, and form a key framework for answering many important questions. Specifically, we show that these geometric correlations facilitate the definition and detection of multidimensional communities, which are sets of nodes that are simultaneously similar in multiple layers. They also enable accurate trans-layer link prediction, meaning that connections in one layer can be predicted by observing the hidden geometric space of another layer. And they allow efficient targeted navigation in the multilayer system using only local knowledge, outperforming navigation in the single layers only if the geometric correlations are sufficiently strong.

  7. Binary hidden Markov models and varieties

    CERN Document Server

    Critch, Andrew J

    2012-01-01

    The technological applications of hidden Markov models have been extremely diverse and successful, including natural language processing, gesture recognition, gene sequencing, and Kalman filtering of physical measurements. HMMs are highly non-linear statistical models, and just as linear models are amenable to linear algebraic techniques, non-linear models are amenable to commutative algebra and algebraic geometry. This paper examines closely those HMMs in which all the random variables, called nodes, are binary. Its main contributions are (1) minimal defining equations for the 4-node model, comprising 21 quadrics and 29 cubics, which were computed using Gr\\"obner bases in the cumulant coordinates of Sturmfels and Zwiernik, and (2) a birational parametrization for every binary HMM, with an explicit inverse for recovering the hidden parameters in terms of observables. The new model parameters in (2) are hence rationally identifiable in the sense of Sullivant, Garcia-Puente, and Spielvogel, and each model's Zar...

  8. Substructure in the Coma Cluster Giants vs Dwarfs

    CERN Document Server

    Edwards, S A; Bridges, T J; Carter, D; Mobasher, B; Poggianti, B M; Edwards, Scott A.; Colless, Matthew; Bridges, Terry J.; Carter, Dave; Mobasher, Bahram; Poggianti, Bianca M.

    2001-01-01

    The processes that form and shape galaxy clusters, such as infall, mergers and dynamical relaxation, tend to generate distinguishable differences between the distributions of a cluster's giant and dwarf galaxies. Thus the dynamics of dwarf galaxies in a cluster can provide valuable insights into its dynamical history. With this in mind, we look for differences between the spatial and velocity distributions of giant (b18) galaxies in the Coma cluster. Our redshift sample contains new measurements from the 2dF and WYFFOS spectrographs, making it more complete at faint magnitudes than any previously studied sample of Coma galaxies. It includes 745 cluster members - 452 giants and 293 dwarfs. We find that the line-of-sight velocity distribution of the giants is significantly non-Gaussian, but not that for the dwarfs. A battery of statistical tests of both the spatial and localised velocity distributions of the galaxies in our sample finds no strong evidence for differences between the giant and dwarf populations....

  9. The hidden epidemic of hypertension.

    Science.gov (United States)

    Grenfell, Robert; Lee, Rebecca; Stavreski, Bill; Page, Karen

    2014-04-01

    The majority of cardiovascular disease (CVD) is caused by risk factors that can be controlled, treated or modified. In terms of attributable deaths, the leading cardiovascular disease risk factor is hypertension. The Australian Health Survey results showed some startling figures-4.6 million adult Australians are hypertensive (>140/90 mmHg). Further, a fifth of the adult population experience hypertension, with more than two out of three not attaining blood pressure target levels. This is despite an estimated cost of $1 billion per annum spent on managing hypertension. It is now well recognised that the level of risk for coronary heart disease is linked to an individual's risk profile. Results indicate that many Australians have multiple risk factors, including hypertension. It could be considered that these numbers provide a proxy indicator of secondary prevention failure. Considerable attention needs to be given to the assessment of the combined risk of those with hypertension enabling effective management of identified, modifiable risk factors. We look forward to presenting the absolute risk profiles when the Australian Health Survey biometric results are released.

  10. The Hidden Gifts of Quiet Kids

    Science.gov (United States)

    Trierweiler, Hannah

    2006-01-01

    The author relates that she was an introvert child. It has always taken her time and energy to find her place in a group. As a grown-up, she still needed quiet time to regroup during a busy day. In this article, the author presents an interview with Marti Olsen Laney, author of "The Hidden Gifts of the Introverted Child." During the interview,…

  11. Finite State Transducers Approximating Hidden Markov Models

    CERN Document Server

    Kempe, A

    1999-01-01

    This paper describes the conversion of a Hidden Markov Model into a sequential transducer that closely approximates the behavior of the stochastic model. This transformation is especially advantageous for part-of-speech tagging because the resulting transducer can be composed with other transducers that encode correction rules for the most frequent tagging errors. The speed of tagging is also improved. The described methods have been implemented and successfully tested on six languages.

  12. Hidden symmetries in dilaton-axion gravity

    CERN Document Server

    Kechkin, O V

    1996-01-01

    Four--dimensional Einstein--Maxwell--dilaton--axion system restricted to space--times with one non--null Killing symmetry is formulated as the three--dimensional gravity coupled sigma--model. Several alternative representations are discussed and the associated hidden symmetries are revealed. The action of target space isometries on the initial set of (non--dualized ) variables is found. New mulicenter solutions are obtained via generating technique based on the formulation in terms of the non--dualized variables.

  13. Killing and letting die: hidden value assumptions.

    Science.gov (United States)

    Atkinson, G

    1983-01-01

    In this paper I argue for several related theses: first, that the distinction between killing and letting die, as it is drawn by ordinary persons in ordinary contexts, is more complex than is generally understood; second, that the key feature of this complexity lies in the presence of a hidden normative component in what appears to be a straightforwardly descriptive distinction; and, third, that this complexity renders the killing/letting die distinction an inadequate and hazardous guide for moral reasoning.

  14. Online Learning in Discrete Hidden Markov Models

    OpenAIRE

    Alamino, Roberto C.; Caticha, Nestor

    2007-01-01

    We present and analyse three online algorithms for learning in discrete Hidden Markov Models (HMMs) and compare them with the Baldi-Chauvin Algorithm. Using the Kullback-Leibler divergence as a measure of generalisation error we draw learning curves in simplified situations. The performance for learning drifting concepts of one of the presented algorithms is analysed and compared with the Baldi-Chauvin algorithm in the same situations. A brief discussion about learning and symmetry breaking b...

  15. Lepton mixing from the hidden sector

    Science.gov (United States)

    Ludl, P. O.; Smirnov, A. Yu.

    2015-10-01

    Experimental results indicate a possible relation between the lepton and quark mixing matrices of the form UPMNS≈VCKM†UX , where UX is a matrix with special structure related to the mechanism of neutrino mass generation. We propose a framework which can realize such a relation. The main ingredients of the framework are the double seesaw mechanism, SO(10) grand unification and a hidden sector of theory. The latter is composed of singlets (fermions and bosons) of the grand unified theory (GUT) symmetry with masses between the GUT and Planck scale. The interactions in this sector obey certain symmetries Ghidden. We explore the conditions under which symmetries Ghidden can produce flavor structures in the visible sector. Here the key elements are the basis-fixing symmetry and mediators which communicate information about properties of the hidden sector to the visible one. The interplay of SO(10) symmetry, basis-fixing symmetry identified as Z2×Z2 and Ghidden can lead to the required form of UX. A different kind of new physics is responsible for generation of the CKM mixing. We present the simplest realizations of the framework which differ by nature of the mediators and by symmetries of the hidden sector.

  16. Otoendoscopic treatment of hidden lesions in otomastoiditis

    Institute of Scientific and Technical Information of China (English)

    LIU Yang; SUN Jian-jun; LIN Yong-sheng; ZHAO Dan-heng; ZHAO Jing; LEI Fei

    2010-01-01

    Background Surgical treatments for chronic suppurative and cholesteatoma otitis media have been discussed for several decades, but recurrences still occur because of the complex dissection required and hidden lesions associated with otomastoiditis. This study investigated the technology and strategy behind the use of otoendoscopic-assisted otosurgery.Methods We reported on hidden lesions in 32 ears of patients with otomastoiditis between November 2006 and January 2009. All the patients were treated with the aid of an otoendoscope. The advantages of otoendoscopy, including multi-angle light scattering, aperture illumination, and magnification of the local operative field, were utilized in otologic microsurgery, and otoendoscopic operative techniques were introduced for operative sites such as the epitympanum, aditus of the antrum, facial recess, sinus tympani and the mastoid tip.Results All patients were followed up from 3 months to 2 years after surgery. All patients recovered well within 3 months following surgery, except for one case of epithelialization of the mastoid cavity occurring 6 months after surgery for cholesteatoma on the cerebellar surface and another case with Bezold's abscess, hyperplastic granulation tissue developed at the antrum.Conclusions Otoendoscopy can overcome the technical deficiency of rectilinearity of the visual axis associated with otomicroscopic illumination, which presents a problem when dealing with otomastoiditis lesions in hidden areas. This technique allows such lesions within the complex three-dimensional structure to be visualized and cleaned. Otoendoscopy thus has significant potential for improving the quality of surgery and reducing the risk of postoperative recurrence.

  17. Dark matter in the hidden gauge theory

    CERN Document Server

    Yamanaka, Nodoka; Gongyo, Shinya; Iida, Hideaki

    2014-01-01

    The cosmological scenario of the dark matter generated in the hidden gauge theory based on the grand unification is discussed. It is found that the stability of the dark matter halo of our Galaxy and the cosmic ray observation constrain, respectively, the dark matter mass and the unification scale between the standard model and the hidden gauge theory sectors. To obtain a phenomenologically consistent thermal evolution, the entropy of the standard model sector needs to be increased. We therefore propose a scenario where the mini-inflation is induced from the potential coupled to the Standard model sector, in particular the Higgs sector. This scenario makes consistent the current dark matter density as well as the baryon-to-photon ratio for the case of pion dark matter. For the glueball or heavy pion of hidden gauge theory, an additional mini-inflation in the standard model sector before the leptogenesis is required. We also propose the possibility to confirm this scenario by known prospective experimental app...

  18. Hidden Worlds of Marine Microbes

    Science.gov (United States)

    Armbrust, E. V.

    2016-12-01

    Every drop of seawater contains fantastically diverse groups of microbes that control key biogeochemical processes in the ocean and determine the habitability of our planet. The challenge is to scale from this world of individual cells to ecosystem function and ultimately to ocean basin processes. Our work begins with microscopic marine diatoms because they are responsible for about twenty percent of the photosynthesis that occurs on Earth each year, they form the base of highly productive marine food webs, and they help regulate past and current fluxes of CO2 into the ocean. Diatoms evolved in a dilute environment where they are never free from the influences of other microbes. We explore the specifics of these interactions via model diatom/bacteria systems that can be manipulated in the laboratory - one includes an antagonistic bacterium that inhibits the growth of diatoms and a second includes a synergistic bacterium that enhances the growth of diatoms. We scale up from the cellular level to population-level interactions through use of our continuous flow cytometer, SeaFlow, which taps into a ship's seawater intake system to provide a continuous read-out of abundance, size and type of the smallest phytoplankton. We use this data to estimate division rates and mortality rates of these phytoplankton across thousands of kilometers of ocean basins. We tie these scales together with genomic approaches in both laboratory experiments and in open ocean field studies to document how interactions with the environment and between microbes drive specific adaptations. Our ultimate goal is to understand how microbial communities will respond to and will help shape future ocean conditions.

  19. Hidden degrees of freedom in aperiodic materials.

    Science.gov (United States)

    Toudic, Bertrand; Garcia, Pilar; Odin, Christophe; Rabiller, Philippe; Ecolivet, Claude; Collet, Eric; Bourges, Philippe; McIntyre, Garry J; Hollingsworth, Mark D; Breczewski, Tomasz

    2008-01-04

    Numerous crystalline materials, including those of bioorganic origin, comprise incommensurate sublattices whose mutual arrangement is described in a superspace framework exceeding three dimensions. We report direct observation by neutron diffraction of superspace symmetry breaking in a solid-solid phase transition of an incommensurate host-guest system: the channel inclusion compound of nonadecane/urea. Strikingly, this phase transition generates a unit cell doubling that concerns only the modulation of one substructure by the other-an internal variable available only in superspace. This unanticipated pathway for degrees of freedom to rearrange leads to a second phase transition, which again is controlled by the higher dimensionality of superspace. These results reveal nature's capacity to explore the increased number of phases allowed in aperiodic crystals.

  20. A Convergent Differential Evolution Algorithm with Hidden Adaptation Selection for Engineering Optimization

    Directory of Open Access Journals (Sweden)

    Zhongbo Hu

    2014-01-01

    Full Text Available Many improved differential Evolution (DE algorithms have emerged as a very competitive class of evolutionary computation more than a decade ago. However, few improved DE algorithms guarantee global convergence in theory. This paper developed a convergent DE algorithm in theory, which employs a self-adaptation scheme for the parameters and two operators, that is, uniform mutation and hidden adaptation selection (haS operators. The parameter self-adaptation and uniform mutation operator enhance the diversity of populations and guarantee ergodicity. The haS can automatically remove some inferior individuals in the process of the enhancing population diversity. The haS controls the proposed algorithm to break the loop of current generation with a small probability. The breaking probability is a hidden adaptation and proportional to the changes of the number of inferior individuals. The proposed algorithm is tested on ten engineering optimization problems taken from IEEE CEC2011.

  1. Hidden laser communications through matter. An application of meV-scale hidden photons

    Energy Technology Data Exchange (ETDEWEB)

    Jaeckel, Joerg [Durham Univ. (United Kingdom). Inst. for Particle Physics and Phenomenology; Redondo, Javier; Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2009-04-15

    Currently, there are a number of light-shining-through-walls experiments searching for hidden photons - light, sub-eV-scale, abelian gauge bosons beyond the standard model which mix kinetically with the standard photon. We show that in the case that one of these experiments finds evidence for hidden photons, laser communications through matter, using methods from free-space optics, can be realized in the very near future, with a channel capacity of more than 1 bit per second, for a distance up to the Earth's diameter. (orig.)

  2. Microwave background constraints on mixing of photons with hidden photons

    Energy Technology Data Exchange (ETDEWEB)

    Mirizzi, Alessandro [Max-Planck-Institut fuer Physik, Muenchen (Germany); Redondo, Javier [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Sigl, Guenter [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2008-12-15

    Various extensions of the Standard Model predict the existence of hidden photons kinetically mixing with the ordinary photon. This mixing leads to oscillations between photons and hidden photons, analogous to the observed oscillations between different neutrino flavors. In this context, we derive new bounds on the photon-hidden photon mixing parameters using the high precision cosmic microwave background spectral data collected by the Far Infrared Absolute Spectrophotometer instrument on board of the Cosmic Background Explorer. Requiring the distortions of the CMB induced by the photon-hidden photon mixing to be smaller than experimental upper limits, this leads to a bound on the mixing angle {chi}{sub 0} hidden photon masses between 10{sup -14} eV and 10{sup -7} eV. This low-mass and low-mixing region of the hidden photon parameter space was previously unconstrained. (orig.)

  3. VISIBLE COSTS AND HIDDEN COSTS IN THE BAKING INDUSTRY

    Directory of Open Access Journals (Sweden)

    Criveanu Maria

    2013-04-01

    Full Text Available Hidden costs are present in the activity of any company, hardly identified in the traditional administrative accounting. The high levels of the hidden costs and their unknown presence have serious consequences on the decisions made by the managers. This paper aims at presenting some aspects related to the hidden costs that occur in the activity of the companies in the baking industry and the possibilities to reduce their level.

  4. Hidden History: A Mobile Application for Discovering Surrounding Landscapes

    OpenAIRE

    2016-01-01

    This thesis work describes the design, development and evaluation of a mobile application called Hidden History. This application lets users discover and explore three types of landscapes (Historic, Scenic and Cultural) using three different modes of discovery (Route, Explore and Tour). Before designing Hidden History, the feature set of other applications that help users explore surrounding landscapes were identified and analyzed. Hidden History was then designed to implement the best fea...

  5. HIDDEN WEB EXTRACTOR DYNAMIC WAY TO UNCOVER THE DEEP WEB

    OpenAIRE

    DR. ANURADHA; BABITA AHUJA

    2012-01-01

    In this era of digital tsunami of information on the web, everyone is completely dependent on the WWW for information retrieval. This has posed a challenging problem in extracting relevant data. Traditional web crawlers focus only on the surface web while the deep web keeps expanding behind the scene. The web databases are hidden behind the query interfaces. In this paper, we propose a Hidden Web Extractor (HWE) that can automatically discover and download data from the Hidden Web databases. ...

  6. ADAPTIVE LEARNING OF HIDDEN MARKOV MODELS FOR EMOTIONAL SPEECH

    Directory of Open Access Journals (Sweden)

    A. V. Tkachenia

    2014-01-01

    Full Text Available An on-line unsupervised algorithm for estimating the hidden Markov models (HMM parame-ters is presented. The problem of hidden Markov models adaptation to emotional speech is solved. To increase the reliability of estimated HMM parameters, a mechanism of forgetting and updating is proposed. A functional block diagram of the hidden Markov models adaptation algorithm is also provided with obtained results, which improve the efficiency of emotional speech recognition.

  7. Hidden Photons in Aharonov-Bohm-Type Experiments

    OpenAIRE

    Arias, Paola; Diaz, Christian; Diaz, Marco Aurelio; Jaeckel, Joerg; Koch, Benjamin; Redondo, Javier

    2016-01-01

    We discuss the Aharonov-Bohm effect in the presence of hidden photons kinetically mixed with the ordinary electromagnetic photons. The hidden photon field causes a slight phase shift in the observable interference pattern. It is then shown how the limited sensitivity of this experiment can be largely improved. The key observation is that the hidden photon field causes a leakage of the ordinary magnetic field into the supposedly field-free region. The direct measurement of this magnetic field ...

  8. VISIBLE COSTS AND HIDDEN COSTS IN THE BAKING INDUSTRY

    OpenAIRE

    Criveanu Maria; Ţaicu Marian

    2013-01-01

    Hidden costs are present in the activity of any company, hardly identified in the traditional administrative accounting. The high levels of the hidden costs and their unknown presence have serious consequences on the decisions made by the managers. This paper aims at presenting some aspects related to the hidden costs that occur in the activity of the companies in the baking industry and the possibilities to reduce their level.

  9. Simple estimates of the hidden beauty pentaquarks masses

    CERN Document Server

    Kopeliovich, Vladimir

    2015-01-01

    The masses of cryptoexotic pentaquarks with hidden beauty are estimated phenomenologically using the results by the LHCb collaboration which discovered recently the cryptoexotic pentaquarks with hidden charm. The expected masses of the hidden beauty pentaquarks are about $10.8\\, GeV$ and $10.7\\,GeV$ in the limit of some kind of heavy quark symmetry. The states with hidden strangeness considered in similar way have masses above $2\\, Gev$, by several hundreds of $MeV$ higher than states discussed previously in connection with the relatively light positive strangeness pentaquark $\\theta^+$.

  10. Critical scaling in hidden state inference for linear Langevin dynamics

    OpenAIRE

    Bravi, Barbara; Sollich, Peter

    2016-01-01

    We consider the problem of inferring the dynamics of unknown (i.e. hidden) nodes from a set of observed trajectories and we study analytically the average prediction error given by the Extended Plefka Expansion applied to it, as presented in [1]. We focus on a stochastic linear dynamics of continuous degrees of freedom interacting via random Gaussian couplings in the infinite network size limit. The expected error on the hidden time courses can be found as the equal-time hidden-to-hidden cova...

  11. Open and hidden agendas of "asymptomatic" patients who request check-up exams

    Directory of Open Access Journals (Sweden)

    Nüesch Reto

    2011-04-01

    Full Text Available Abstract Background Current guidelines for a check-up recommend routine screening not triggered by specific symptoms for some known risk factors and diseases in the general population. Patients' perceptions and expectations regarding a check-up exam may differ from these principles. However, quantitative and qualitative data about the discrepancy between patient- and provider expectations for this type of clinic consultation is lacking. Methods For a year, we prospectively enrolled 66 patients who explicitly requested a "check-up" at our medical outpatient division. All patients actively denied upon prompting having any symptoms or specific health concerns at the time they made their appointment. All consultations were videotaped and analysed for information about spontaneously mentioned symptoms and reasons for the clinic consultation ("open agendas" and for cues to hidden patient agendas using the Roter interaction analysis system (RIAS. Results All patients initially declared to be asymptomatic but this was ultimately the case in only 7 out of 66 patients. The remaining 59 patients spontaneously mentioned a mean of 4.2 ± 3.3 symptoms during their first consultation. In 23 patients a total of 31 hidden agendas were revealed. The primary categories for hidden agendas were health concerns, psychosocial concerns and the patient's concept of disease. Conclusions The majority of patients requesting a general check-up tend to be motivated by specific symptoms and health concerns and are not "asymptomatic" patients who primarily come for preventive issues. Furthermore, physicians must be alert for possible hidden agendas, as one in three patients have one or more hidden reasons for requesting a check-up.

  12. Error statistics of hidden Markov model and hidden Boltzmann model results

    Directory of Open Access Journals (Sweden)

    Newberg Lee A

    2009-07-01

    Full Text Available Abstract Background Hidden Markov models and hidden Boltzmann models are employed in computational biology and a variety of other scientific fields for a variety of analyses of sequential data. Whether the associated algorithms are used to compute an actual probability or, more generally, an odds ratio or some other score, a frequent requirement is that the error statistics of a given score be known. What is the chance that random data would achieve that score or better? What is the chance that a real signal would achieve a given score threshold? Results Here we present a novel general approach to estimating these false positive and true positive rates that is significantly more efficient than are existing general approaches. We validate the technique via an implementation within the HMMER 3.0 package, which scans DNA or protein sequence databases for patterns of interest, using a profile-HMM. Conclusion The new approach is faster than general naïve sampling approaches, and more general than other current approaches. It provides an efficient mechanism by which to estimate error statistics for hidden Markov model and hidden Boltzmann model results.

  13. Error statistics of hidden Markov model and hidden Boltzmann model results

    Science.gov (United States)

    Newberg, Lee A

    2009-01-01

    Background Hidden Markov models and hidden Boltzmann models are employed in computational biology and a variety of other scientific fields for a variety of analyses of sequential data. Whether the associated algorithms are used to compute an actual probability or, more generally, an odds ratio or some other score, a frequent requirement is that the error statistics of a given score be known. What is the chance that random data would achieve that score or better? What is the chance that a real signal would achieve a given score threshold? Results Here we present a novel general approach to estimating these false positive and true positive rates that is significantly more efficient than are existing general approaches. We validate the technique via an implementation within the HMMER 3.0 package, which scans DNA or protein sequence databases for patterns of interest, using a profile-HMM. Conclusion The new approach is faster than general naïve sampling approaches, and more general than other current approaches. It provides an efficient mechanism by which to estimate error statistics for hidden Markov model and hidden Boltzmann model results. PMID:19589158

  14. Evolving the structure of hidden Markov Models

    DEFF Research Database (Denmark)

    won, K. J.; Prugel-Bennett, A.; Krogh, A.

    2006-01-01

    A genetic algorithm (GA) is proposed for finding the structure of hidden Markov Models (HMMs) used for biological sequence analysis. The GA is designed to preserve biologically meaningful building blocks. The search through the space of HMM structures is combined with optimization of the emission...... and transition probabilities using the classic Baum-Welch algorithm. The system is tested on the problem of finding the promoter and coding region of C. jejuni. The resulting HMM has a superior discrimination ability to a handcrafted model that has been published in the literature....

  15. OFDM System Channel Estimation with Hidden Pilot

    Institute of Scientific and Technical Information of China (English)

    YANG Feng; LIN Cheng-yu; ZHANG Wen-jun

    2007-01-01

    Channel estimation using pilot is common used in OFDM system. The pilot is usually time division multiplexed with the informative sequence. One of the main drawbacks is bandwidth losing. In this paper, a new method was proposed to perform channel estimation in OFDM system. The pilot is arithmetically added to the output of OFDM modulator. Receiver uses the hidden pilot to get an accurate estimation of the channel. Then pilot is removed after channel estimation. The Cramer-Rao lower bound for this method was deprived. The performance of the algorithm is then shown. Compared with traditional methods, the proposed algorithm increases the bandwidth efficiency dramatically.

  16. Pruning Boltzmann networks and hidden Markov models

    DEFF Research Database (Denmark)

    Pedersen, Morten With; Stork, D.

    1996-01-01

    We present sensitivity-based pruning algorithms for general Boltzmann networks. Central to our methods is the efficient calculation of a second-order approximation to the true weight saliencies in a cross-entropy error. Building upon previous work which shows a formal correspondence between linear...... Boltzmann chains and hidden Markov models (HMMs), we argue that our method can be applied to HMMs as well. We illustrate pruning on Boltzmann zippers, which are equivalent to two HMMs with cross-connection links. We verify that our second-order approximation preserves the rank ordering of weight saliencies...

  17. Hidden photon CDM search at Tokyo

    CERN Document Server

    Suzuki, Jun'ya; Horie, Tomoki; Minowa, Makoto

    2015-01-01

    We report on a search for hidden photon cold dark matter (HP CDM) using a novel technique with a dish antenna. We constructed two independent apparatus: one is aiming at the detection of the HP with a mass of $\\sim\\,\\rm{eV}$ which employs optical instruments, and the other is for a mass of $\\sim5\\times10^{-5}\\, \\rm{eV}$ utilizing a commercially available parabolic antenna facing on a plane reflector. From the result of the measurements, we found no evidence for the existence of HP CDM and set upper limits on the photon-HP mixing parameter $\\chi$.

  18. Maurice Halbwachs: Official and hidden memory

    Directory of Open Access Journals (Sweden)

    Carretero, Angel

    2008-05-01

    Full Text Available This article tries to show, in general terms, how Maurice Halbwachs has discovered presence and vitality in the collective memorieswhich have been excluded from the socially-institutionalized world. In order to decipher his opaque writing, one should try for a sociology of the depths, for a sociological look that, separating itself from the dominant positivism of the social sciences, manages to penetrate the hidden logic that permanently underlies social life. This article seeks to uncover the nature of a collective memory that respects the vicissitudes of time, as well as its difficult relations both with official memory and with the dominant historical record.

  19. Die Beharrlichkeit im Verborgenen Hidden Persistence

    Directory of Open Access Journals (Sweden)

    Paula-Irene Villa

    2003-07-01

    Full Text Available Karin Flaake geht in ihrer psychoanalytischen Interpretation innerfamilialer Konstellationen der Frage nach, wie das Zur-Frau-Werden von jungen Frauen erlebt wird. Dabei kommt den körperliche Wandlungsprozessen der Pubertät und den darin eingelagerten expliziten sowie verborgenen Deutungen des Weiblichen – vor allem des weiblichen Körpers – durch die Eltern eine prominente Rolle zu.Karin Flaake’s psychoanalytical intepretations of family constellations explore how young women experience their coming of age and entering womanhood. Her analysis focuses on the bodily changes which women undergo during puberty and the explicit as well as hidden meanings assigned to them by the parents.

  20. Scaling dimensions in hidden Kerr/CFT

    CERN Document Server

    Lowe, David A; Skanata, Antun

    2011-01-01

    It has been proposed that a hidden conformal field theory (CFT) governs the dynamics of low frequency scattering in a general Kerr black hole background. We further investigate this correspondence by mapping higher order corrections to the massless wave equations in a Kerr background to an expansion within the CFT in terms of higher dimension operators. This implies the presence of infinite towers of CFT primary operators with positive conformal dimensions compatible with unitarity. The exact Kerr background softly breaks the conformal symmetry and the scaling dimensions of these operators run with frequency. The scale-invariant fixed point is dual to a degenerate case of flat spacetime.

  1. Hidden Kerr/CFT at finite frequencies

    CERN Document Server

    Lowe, David A; Skanata, Antun

    2013-01-01

    Massless fields propagating in a generic Kerr black hole background enjoy a hidden SL(2,R)xSL(2,R) symmetry. We determine how the exact mode functions decompose into representations of this symmetry group. This extends earlier results on the low frequency limit of the massless scalar case to finite frequencies and general spin. As an application, we numerically determine the parameters of the representations that appear in quasinormal modes. These results represent a first step to formulating a more precise mapping to a holographic dual conformal field theory for generic black holes.

  2. A New Hidden Web Crawling Approach

    OpenAIRE

    L.Saoudi; A.Boukerram; S.Mhamedi

    2015-01-01

    Traditional search engines deal with the Surface Web which is a set of Web pages directly accessible through hyperlinks and ignores a large part of the Web called hidden Web which is a great amount of valuable information of online database which is “hidden” behind the query forms. To access to those information the crawler have to fill the forms with a valid data, for this reason we propose a new approach which use SQLI technique in order to find the most promising keywords of a specific dom...

  3. Hidden Scale Invariance in Condensed Matter

    DEFF Research Database (Denmark)

    Dyre, J. C.

    2014-01-01

    . This means that the phase diagram becomes effectively one-dimensional with regard to several physical properties. Liquids and solids with isomorphs include most or all van der Waals bonded systems and metals, as well as weakly ionic or dipolar systems. On the other hand, systems with directional bonding...... (hydrogen bonds or covalent bonds) or strong Coulomb forces generally do not exhibit hidden scale invariance. The article reviews the theory behind this picture of condensed matter and the evidence for it coming from computer simulations and experiments...

  4. Genetic Algorithms Principles Towards Hidden Markov Model

    Directory of Open Access Journals (Sweden)

    Nabil M. Hewahi

    2011-10-01

    Full Text Available In this paper we propose a general approach based on Genetic Algorithms (GAs to evolve Hidden Markov Models (HMM. The problem appears when experts assign probability values for HMM, they use only some limited inputs. The assigned probability values might not be accurate to serve in other cases related to the same domain. We introduce an approach based on GAs to find
    out the suitable probability values for the HMM to be mostly correct in more cases than what have been used to assign the probability values.

  5. Fifty Years After, Hidden Children Speak

    Directory of Open Access Journals (Sweden)

    Léa Marcou

    2008-06-01

    Full Text Available “For fifty years, I have not spoken of my childhood years in France during the second world war. A hidden child, I lived under a false name amongst unknown people, being careful – as I had been taught – not to reveal, by a gesture or by a word, that I was Jewish. I knew I was in danger, still not understanding why and I was constantly afraid. I didn't know whether I would see again one day my parents from whom I had been suddenly taken away. Nonetheless what were my pains compared to those of...

  6. Detecting Structural Breaks using Hidden Markov Models

    DEFF Research Database (Denmark)

    Ntantamis, Christos

    Testing for structural breaks and identifying their location is essential for econometric modeling. In this paper, a Hidden Markov Model (HMM) approach is used in order to perform these tasks. Breaks are defined as the data points where the underlying Markov Chain switches from one state to another....... The locations of the breaks are subsequently obtained by assigning states to data points according to the Maximum Posterior Mode (MPM) algorithm. The Integrated Classification Likelihood-Bayesian Information Criterion (ICL-BIC) allows for the determination of the number of regimes by taking into account...... in the monetary policy of United States, the dierent functional form being variants of the Taylor (1993) rule....

  7. Uncovering the Hidden Costs of Offshoring

    DEFF Research Database (Denmark)

    Larsen, Marcus M.; Manning, Stephan; Pedersen, Torben

    2013-01-01

    This study investigates estimation errors due to hidden costs—the costs of implementation that are neglected in strategic decision-making processes—in the context of services offshoring. Based on data from the Offshoring Research Network, we find that decision makers are more likely to make cost......-estimation errors given increasing configuration and task complexity in captive offshoring and offshore outsourcing, respectively. Moreover, we show that experience and a strong orientation toward organizational design in the offshoring strategy reduce the cost-estimation errors that follow from complexity. Our...

  8. Chemical composition of stars in kinematical substructures of the galactic disk

    Directory of Open Access Journals (Sweden)

    Gorbaneva T.I.

    2012-02-01

    Full Text Available The Y, Zr, La, Ce, Nd , Sm and Eu abundances were found in LTE approach, and the abundance of Ba was computed in NLTE approximation for 280 FGK dwarfs in the region of metallicity of − 1<[Fe]< + 0.3. The selection of stars belonging to thin and thick disks and the stream Hercules was made on kinematic criteria. The analysis of enrichment of the different substructures of the Galaxy with α-element (Mg, Si, the iron peak (Ni and neutron-capture elements was carried out.

  9. Study of Jet Substructure in the ATLAS Experiment using Distributed Analysis within Spanish Tier-2 infrastructures

    OpenAIRE

    Oliver García, Elena

    2013-01-01

    Study of Jet Substructure in the ATLAS experiment using Distributed Analysis within Spanish Tier-2 Infrastructures (Estudio de Subestructura de Jets en el experimento ATLAS usando Análisis Distribuido dentro de las Infraestructuras del Tier-2 Español) Resumen en español 1. Motivación En el Large Hadron Collider (LHC) se producen partículas consideradas objetos ‘boosted’ donde sus productos de desintegración se concentran en una pequeña parte del detector. El estudio de estos ...

  10. An early neutrino experiment: how we missed quark substructure in 1963

    Science.gov (United States)

    Perkins, D. H.

    2013-12-01

    Some 50 years after the event seems to be an appropriate time at which to take a long look back at one of the early neutrino experiments at CERN. This report is principally about a failure in a 1963 bubble chamber experiment to detect substructure in the nucleon, a year before the quark concept was invented by Gell-Mann and Zweig, and some five years before the existence of quarks as real dynamical objects was definitely established in deep inelastic electron scattering experiments at Stanford.

  11. Cold Dark Matter Substructure and Galactic Disks I: Morphological Signatures of Hierarchical SatelliteAccretion

    Energy Technology Data Exchange (ETDEWEB)

    Kazantzidis, Stelios; Bullock, James S.; Zentner, Andrew R.; Kravtsov, Andrey V.; Moustakas, Leonidas A.

    2007-12-03

    We conduct a series of high-resolution, fully self-consistent dissipation less N-body simulations to investigate the cumulative effect of substructure mergers onto thin disk galaxies in the context of the {Lambda}CDM paradigm of structure formation. Our simulation campaign is based on a hybrid approach combining cosmological simulations and controlled numerical experiments. Substructure mass functions, orbital distributions, internal structures, and accretion times are culled directly from cosmological simulations of galaxy-sized cold dark matter (CDM) halos. We demonstrate that accretions of massive subhalos onto the central regions of host halos, where the galactic disk resides, since z {approx} 1 should be common occurrences. In contrast, extremely few satellites in present-day CDM halos are likely to have a significant impact on the disk structure. This is due to the fact that massive subhalos with small orbital pericenters that are most capable of strongly perturbing the disk become either tidally disrupted or suffer substantial mass loss prior to z = 0. One host halo merger history is subsequently used to seed controlled N-body experiments of repeated satellite impacts on an initially-thin Milky Way-type disk galaxy. These simulations track the effects of six dark matter substructures, with initial masses in the range {approx} (0.7-2) x 10{sup 10} M{sub {circle_dot}} ({approx} 20-60% of the disk mass), crossing the disk in the past {approx} 8 Gyr. We show that these accretion events produce several distinctive observational signatures in the stellar disk including: a long-lived, low-surface brightness, ring-like feature in the outskirts; a significant flare; a central bar; and faint filamentary structures that (spuriously) resemble tidal streams in configuration space. The final distribution of disk stars exhibits a complex vertical structure that is well-described by a standard 'thin-thick' disk decomposition, where the 'thick' disk

  12. Cold Dark Matter Substructure and Galactic Disks I: Morphological Signatures of Hierarchical SatelliteAccretion

    Energy Technology Data Exchange (ETDEWEB)

    Kazantzidis, Stelios; Bullock, James S.; Zentner, Andrew R.; Kravtsov, Andrey V.; Moustakas, Leonidas A.

    2007-12-03

    We conduct a series of high-resolution, fully self-consistent dissipation less N-body simulations to investigate the cumulative effect of substructure mergers onto thin disk galaxies in the context of the {Lambda}CDM paradigm of structure formation. Our simulation campaign is based on a hybrid approach combining cosmological simulations and controlled numerical experiments. Substructure mass functions, orbital distributions, internal structures, and accretion times are culled directly from cosmological simulations of galaxy-sized cold dark matter (CDM) halos. We demonstrate that accretions of massive subhalos onto the central regions of host halos, where the galactic disk resides, since z {approx} 1 should be common occurrences. In contrast, extremely few satellites in present-day CDM halos are likely to have a significant impact on the disk structure. This is due to the fact that massive subhalos with small orbital pericenters that are most capable of strongly perturbing the disk become either tidally disrupted or suffer substantial mass loss prior to z = 0. One host halo merger history is subsequently used to seed controlled N-body experiments of repeated satellite impacts on an initially-thin Milky Way-type disk galaxy. These simulations track the effects of six dark matter substructures, with initial masses in the range {approx} (0.7-2) x 10{sup 10} M{sub {circle_dot}} ({approx} 20-60% of the disk mass), crossing the disk in the past {approx} 8 Gyr. We show that these accretion events produce several distinctive observational signatures in the stellar disk including: a long-lived, low-surface brightness, ring-like feature in the outskirts; a significant flare; a central bar; and faint filamentary structures that (spuriously) resemble tidal streams in configuration space. The final distribution of disk stars exhibits a complex vertical structure that is well-described by a standard 'thin-thick' disk decomposition, where the 'thick' disk

  13. Structure and substructure analysis of DAFT/FADA galaxy clusters in the [0.4-0.9] redshift range

    CERN Document Server

    Guennou, L; Durret, F; Neto, G B Lima; Ulmer, M P; Clowe, D; LeBrun, V; Martinet, N; Allam, S; Annis, J; Basa, S; Benoist, C; Biviano, A; Cappi, A; Cypriano, E S; Gavazzi, R; Halliday, C; Ilbert, O; Jullo, E; Just, D; Limousin, M; Márquez, I; Mazure, A; Murphy, K J; Plana, H; Rostagni, F; Russeil, D; Schirmer, M; Slezak, E; Tucker, D; Zaritsky, D; Ziegler, B

    2013-01-01

    We analyse the structures of all the clusters in the DAFT/FADA survey for which XMM-Newton and/or a sufficient number of galaxy redshifts in the cluster range is available, with the aim of detecting substructures and evidence for merging events. These properties are discussed in the framework of standard cold dark matter cosmology.XMM-Newton data were available for 32 clusters, for which we derive the X-ray luminosity and a global X-ray temperature for 25 of them. For 23 clusters we were able to fit the X-ray emissivity with a beta-model and subtract it to detect substructures in the X-ray gas. A dynamical analysis based on the SG method was applied to the clusters having at least 15 spectroscopic galaxy redshifts in the cluster range: 18 X-ray clusters and 11 clusters with no X-ray data. Only major substructures will be detected. Ten substructures were detected both in X-rays and by the SG method. Most of the substructures detected both in X-rays and with the SG method are probably at their first cluster per...

  14. Women's hidden transcripts about abortion in Brazil.

    Science.gov (United States)

    Nations, M K; Misago, C; Fonseca, W; Correia, L L; Campbell, O M

    1997-06-01

    Two folk medical conditions, "delayed" (atrasada) and "suspended" (suspendida) menstruation, are described as perceived by poor Brazilian women in Northeast Brazil. Culturally prescribed methods to "regulate" these conditions and provoke menstrual bleeding are also described, including ingesting herbal remedies, patent drugs, and modern pharmaceuticals. The ingestion of such self-administered remedies is facilitated by the cognitive ambiguity, euphemisms, folklore, etc., which surround conception and gestation. The authors argue that the ethnomedical conditions of "delayed" and "suspended" menstruation and subsequent menstrual regulation are part of the "hidden reproductive transcript" of poor and powerless Brazilian women. Through popular culture, they voice their collective dissent to the official, public opinion about the illegality and immorality of induced abortion and the chronic lack of family planning services in Northeast Brazil. While many health professionals consider women's explanations of menstrual regulation as a "cover-up" for self-induced abortions, such popular justifications may represent either an unconscious or artful manipulation of hegemonic, anti-abortion ideology expressed in prudent, unobtrusive and veiled ways. The development of safer abortion alternatives should consider women's hidden reproductive transcripts.

  15. Atlas of solar hidden photon emission

    Energy Technology Data Exchange (ETDEWEB)

    Redondo, Javier [Departamento de Física Teórica, Universidad de Zaragoza,Pedro Cerbuna 12, E-50009, Zaragoza (Spain); Max-Planck-Institut für Physik, Werner-Heisenberg-Institut,Föhringer Ring 6, 80805 München (Germany)

    2015-07-20

    Hidden photons, gauge bosons of a U(1) symmetry of a hidden sector, can constitute the dark matter of the universe and a smoking gun for large volume compactifications of string theory. In the sub-eV mass range, a possible discovery experiment consists on searching the copious flux of these particles emitted from the Sun in a helioscope setup à la Sikivie. In this paper, we compute in great detail the flux of HPs from the Sun, a necessary ingredient for interpreting such experiments. We provide a detailed exposition of transverse photon-HP oscillations in inhomogenous media, with special focus on resonance oscillations, which play a leading role in many cases. The region of the Sun emitting HPs resonantly is a thin spherical shell for which we justify an averaged-emission formula and which implies a distinctive morphology of the angular distribution of HPs on Earth in many cases. Low mass HPs with energies in the visible and IR have resonances very close to the photosphere where the solar plasma is not fully ionised and requires building a detailed model of solar refraction and absorption. We present results for a broad range of HP masses (from 0–1 keV) and energies (from the IR to the X-ray range), the most complete atlas of solar HP emission to date.

  16. Epitope discovery with phylogenetic hidden Markov models.

    LENUS (Irish Health Repository)

    Lacerda, Miguel

    2010-05-01

    Existing methods for the prediction of immunologically active T-cell epitopes are based on the amino acid sequence or structure of pathogen proteins. Additional information regarding the locations of epitopes may be acquired by considering the evolution of viruses in hosts with different immune backgrounds. In particular, immune-dependent evolutionary patterns at sites within or near T-cell epitopes can be used to enhance epitope identification. We have developed a mutation-selection model of T-cell epitope evolution that allows the human leukocyte antigen (HLA) genotype of the host to influence the evolutionary process. This is one of the first examples of the incorporation of environmental parameters into a phylogenetic model and has many other potential applications where the selection pressures exerted on an organism can be related directly to environmental factors. We combine this novel evolutionary model with a hidden Markov model to identify contiguous amino acid positions that appear to evolve under immune pressure in the presence of specific host immune alleles and that therefore represent potential epitopes. This phylogenetic hidden Markov model provides a rigorous probabilistic framework that can be combined with sequence or structural information to improve epitope prediction. As a demonstration, we apply the model to a data set of HIV-1 protein-coding sequences and host HLA genotypes.

  17. Atlas of solar hidden photon emission

    CERN Document Server

    Redondo, Javier

    2015-01-01

    Hidden photons, gauge bosons of a U(1) symmetry of a hidden sector, can constitute the dark matter of the universe and a smoking gun for large volume compactifications of string theory. In the sub-eV mass range, a possible discovery experiment consists on searching the copious flux of these particles emitted from the Sun in a helioscope setup \\`a la Sikivie. In this paper, we compute the flux of transversely polarised HPs from the Sun, a necessary ingredient for interpreting such experiments. We provide a detailed exposition of photon-HP oscillations in inhomogenous media, with special focus on resonance oscillations, which play a leading role in many cases. The region of the Sun emitting HPs resonantly is a thin spherical shell for which we justify an averaged-emission formula and which implies a distinctive morphology of the angular distribution of HPs on Earth in many cases. Low mass HPs with energies in the visible and IR have resonances very close to the photosphere where the solar plasma is not fully io...

  18. Quantum Hidden Subgroup Problems A Mathematical Perspective

    CERN Document Server

    Lomonaco, S J; Lomonaco, Samuel J.; Kauffman, Louis H.

    2002-01-01

    The ultimate objective of this paper is to create a stepping stone to the development of new quantum algorithms. The strategy chosen is to begin by focusing on the class of abelian quantum hidden subgroup algorithms, i.e., the class of abelian algorithms of the Shor/Simon genre. Our strategy is to make this class of algorithms as mathematically transparent as possible. By the phrase "mathematically transparent" we mean to expose, to bring to the surface, and to make explicit the concealed mathematical structures that are inherently and fundamentally a part of such algorithms. In so doing, we create symbolic abelian quantum hidden subgroup algorithms that are analogous to the those symbolic algorithms found within such software packages as Axiom, Cayley, Maple, Mathematica, and Magma. As a spin-off of this effort, we create three different generalizations of Shor's quantum factoring algorithm to free abelian groups of finite rank. We refer to these algorithms as wandering (or vintage Z_Q) Shor algorithms. They...

  19. ESO's Hidden Treasures Brought to Light

    Science.gov (United States)

    2011-01-01

    ESO's Hidden Treasures 2010 astrophotography competition attracted nearly 100 entries, and ESO is delighted to announce the winners. Hidden Treasures gave amateur astronomers the opportunity to search ESO's vast archives of astronomical data for a well-hidden cosmic gem. Astronomy enthusiast Igor Chekalin from Russia won the first prize in this difficult but rewarding challenge - the trip of a lifetime to ESO's Very Large Telescope at Paranal, Chile. The pictures of the Universe that can be seen in ESO's releases are impressive. However, many hours of skilful work are required to assemble the raw greyscale data captured by the telescopes into these colourful images, correcting them for distortions and unwanted signatures of the instrument, and enhancing them so as to bring out the details contained in the astronomical data. ESO has a team of professional image processors, but for the ESO's Hidden Treasures 2010 competition, the experts decided to give astronomy and photography enthusiasts the opportunity to show the world what they could do with the mammoth amount of data contained in ESO's archives. The enthusiasts who responded to the call submitted nearly 100 entries in total - far exceeding initial expectations, given the difficult nature of the challenge. "We were completely taken aback both by the quantity and the quality of the images that were submitted. This was not a challenge for the faint-hearted, requiring both an advanced knowledge of data processing and an artistic eye. We are thrilled to have discovered so many talented people," said Lars Lindberg Christensen, Head of ESO's education and Public Outreach Department. Digging through many terabytes of professional astronomical data, the entrants had to identify a series of greyscale images of a celestial object that would reveal the hidden beauty of our Universe. The chance of a great reward for the lucky winner was enough to spur on the competitors; the first prize being a trip to ESO's Very Large

  20. Hidden Markov Model for Stock Selection

    Directory of Open Access Journals (Sweden)

    Nguyet Nguyen

    2015-10-01

    Full Text Available The hidden Markov model (HMM is typically used to predict the hidden regimes of observation data. Therefore, this model finds applications in many different areas, such as speech recognition systems, computational molecular biology and financial market predictions. In this paper, we use HMM for stock selection. We first use HMM to make monthly regime predictions for the four macroeconomic variables: inflation (consumer price index (CPI, industrial production index (INDPRO, stock market index (S&P 500 and market volatility (VIX. At the end of each month, we calibrate HMM’s parameters for each of these economic variables and predict its regimes for the next month. We then look back into historical data to find the time periods for which the four variables had similar regimes with the forecasted regimes. Within those similar periods, we analyze all of the S&P 500 stocks to identify which stock characteristics have been well rewarded during the time periods and assign scores and corresponding weights for each of the stock characteristics. A composite score of each stock is calculated based on the scores and weights of its features. Based on this algorithm, we choose the 50 top ranking stocks to buy. We compare the performances of the portfolio with the benchmark index, S&P 500. With an initial investment of $100 in December 1999, over 15 years, in December 2014, our portfolio had an average gain per annum of 14.9% versus 2.3% for the S&P 500.

  1. Hidden charm molecules in finite volume

    CERN Document Server

    Albaladejo, Miguel; Nieves, Juan; Oset, Eulogio

    2013-01-01

    In the present paper we address the interaction of pairs of charmed mesons with hidden charm in a finite box. We use the interaction from a recent model based on heavy quark spin symmetry that predicts molecules of hidden charm in the infinite volume. The energy levels in the box are generated within this model, and from them some synthetic data are generated. These data are then employed to study the inverse problem of getting the energies of the bound states and phase shifts for $D \\bar D$ or $D^* {\\bar D}^*$. Different strategies are investigated using the lowest two levels for different values of the box size, carrying a study of the errors produced. Starting from the upper level, fits to the synthetic data are carried out to determine the scattering length and effective range plus the binding energy of the ground state. A similar strategy using the effective range formula is considered with a simultaneous fit to the two levels, one above and the other one below threshold. This method turns out to be more...

  2. Laser experiments explore the hidden sector

    Energy Technology Data Exchange (ETDEWEB)

    Ahlers, M. [Oxford Univ. (United Kingdom). Rudolf Peierls Centre for Theoretical Physics; Gies, H. [Heidelberg Univ. (Germany). Inst. fuer Theoretische Physik; Jaeckel, J. [Heidelberg Univ. (Germany). Inst. fuer Theoretische Physik]|[Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology; Redondo, J.; Ringwald, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2007-11-15

    Recently, the laser experiments BMV and GammeV, searching for light shining through walls, have published data and calculated new limits on the allowed masses and couplings for axion-like particles. In this note we point out that these experiments can serve to constrain a much wider variety of hidden-sector particles such as, e.g., minicharged particles and hidden-sector photons. The new experiments improve the existing bounds from the older BFRT experiment by a factor of two. Moreover, we use the new PVLAS constraints on a possible rotation and ellipticity of light after it has passed through a strong magnetic field to constrain pure minicharged particle models. For masses

  3. Bayesian structural inference for hidden processes.

    Science.gov (United States)

    Strelioff, Christopher C; Crutchfield, James P

    2014-04-01

    We introduce a Bayesian approach to discovering patterns in structurally complex processes. The proposed method of Bayesian structural inference (BSI) relies on a set of candidate unifilar hidden Markov model (uHMM) topologies for inference of process structure from a data series. We employ a recently developed exact enumeration of topological ε-machines. (A sequel then removes the topological restriction.) This subset of the uHMM topologies has the added benefit that inferred models are guaranteed to be ε-machines, irrespective of estimated transition probabilities. Properties of ε-machines and uHMMs allow for the derivation of analytic expressions for estimating transition probabilities, inferring start states, and comparing the posterior probability of candidate model topologies, despite process internal structure being only indirectly present in data. We demonstrate BSI's effectiveness in estimating a process's randomness, as reflected by the Shannon entropy rate, and its structure, as quantified by the statistical complexity. We also compare using the posterior distribution over candidate models and the single, maximum a posteriori model for point estimation and show that the former more accurately reflects uncertainty in estimated values. We apply BSI to in-class examples of finite- and infinite-order Markov processes, as well to an out-of-class, infinite-state hidden process.

  4. Quantum algorithm for identifying hidden polynomial function graphs

    NARCIS (Netherlands)

    Decker, T.; Draisma, J.; Wocjan, P.

    2009-01-01

    We consider a natural generalization of an abelian Hidden Subgroup Problem where the subgroups and their cosets correspond to graphs of linear functions over a finite field F with d elements. The hidden functions of the generalized problem are not restricted to be linear but can also be m-variate po

  5. Hidden attractor in the Rabinovich system, Chua circuits and PLL

    Science.gov (United States)

    Kuznetsov, N. V.; Leonov, G. A.; Mokaev, T. N.; Seledzhi, S. M.

    2016-06-01

    In this report the existence of hidden attractors in Rabinovich system, phase-locked loop and coupled Chua circuits is considered. It is shown that the existence of hidden attractors may complicate the analysis of the systems and significantly affect the synchronization.

  6. Hidden Curriculum as One of Current Issue of Curriculum

    Science.gov (United States)

    Alsubaie, Merfat Ayesh

    2015-01-01

    There are several issues in the education system, especially in the curriculum field that affect education. Hidden curriculum is one of current controversial curriculum issues. Many hidden curricular issues are the result of assumptions and expectations that are not formally communicated, established, or conveyed within the learning environment.…

  7. Searching for hidden sector in multiparticle production at LHC

    Directory of Open Access Journals (Sweden)

    Miguel-Angel Sanchis-Lozano

    2016-03-01

    Full Text Available We study the impact of a hidden sector beyond the Standard Model, e.g. a Hidden Valley model, on factorial moments and cumulants of multiplicity distributions in multiparticle production with a special emphasis on the prospects for LHC results.

  8. Secret Codes: The Hidden Curriculum of Semantic Web Technologies

    Science.gov (United States)

    Edwards, Richard; Carmichael, Patrick

    2012-01-01

    There is a long tradition in education of examination of the hidden curriculum, those elements which are implicit or tacit to the formal goals of education. This article draws upon that tradition to open up for investigation the hidden curriculum and assumptions about students and knowledge that are embedded in the coding undertaken to facilitate…

  9. Secret Codes: The Hidden Curriculum of Semantic Web Technologies

    Science.gov (United States)

    Edwards, Richard; Carmichael, Patrick

    2012-01-01

    There is a long tradition in education of examination of the hidden curriculum, those elements which are implicit or tacit to the formal goals of education. This article draws upon that tradition to open up for investigation the hidden curriculum and assumptions about students and knowledge that are embedded in the coding undertaken to facilitate…

  10. Seuss's Butter Battle Book: Is There Hidden Harm?

    Science.gov (United States)

    Van Cleaf, David W.; Martin, Rita J.

    1986-01-01

    Examines whether elementary school children relate to the "harmful hidden message" about nuclear war in Dr. Seuss's THE BUTTER BATTLE BOOK. After ascertaining the children's cognitive level, they participated in activities to find hidden meanings in stories, including Seuss's book. Students failed to identify the nuclear war message in Seuss's…

  11. An introduction to hidden Markov models for biological sequences

    DEFF Research Database (Denmark)

    Krogh, Anders Stærmose

    1998-01-01

    A non-matematical tutorial on hidden Markov models (HMMs) plus a description of one of the applications of HMMs: gene finding.......A non-matematical tutorial on hidden Markov models (HMMs) plus a description of one of the applications of HMMs: gene finding....

  12. Detecting Hidden Hierarchy of Non Hierarchical Terrorist Networks

    DEFF Research Database (Denmark)

    Memon, Nasrullah

    to analyze terrorist networks and prioritize their targets. Applying recently introduced mathematical methods for constructing the hidden hierarchy of "nonhierarchical" terrorist networks; we present case studies of the terrorist attacks occurred / planned in the past, in order to identify hidden hierarchy...

  13. Development of a High-fidelity Experimental Substructure Test Rig for Grid-scored Sandwich Panels in Wind Turbine Blades

    DEFF Research Database (Denmark)

    Laustsen, Steffen; Lund, Erik; Kühlmeier, L.;

    2014-01-01

    This paper outlines high-fidelity experimental substructure testing of sandwich panels which constitute the aerodynamic outer shell of modern wind turbine blades. A full-scale structural experimental and numerical characterisation of a composite wind turbine blade has been conducted. The developm...... of substructure tests for composite wind turbine blades. Furthermore, recommendations on the use of grid-scored sandwich structures in wind turbine blades are presented, which outline the sensitivity in terms of quasi-static strength to the established loading conditions.......This paper outlines high-fidelity experimental substructure testing of sandwich panels which constitute the aerodynamic outer shell of modern wind turbine blades. A full-scale structural experimental and numerical characterisation of a composite wind turbine blade has been conducted...

  14. Relationship among wear-resistance of three-body abrasion,substructure and property in martensite steels

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The effects of subsurface hardness on wear-resistance of martensitic steel 20Cr, 40CrSi, 60Mn, T8 and T10 in three-body abrasion under static load was investigated. It shows that the characteristic ofthe subsurface hardness distribution and the abrasive wear resistanceis related to the substructure near the worn surface. The substructure of the tested martensite steel has an apparent relationship with thecarbon content and steels with moderate carbon content and hardness exhibit good resistance to abrasive wear. The competition of the work-hardening effect and the temper softening effect, which resulted from deformation and friction heat generating during abrasive wear is considered to be a main reason for the relation among wear-resistance, hardness and substructure. At the test conditions, the wear-resistance of 40CrSi is the best.

  15. Motion and deformation estimation from medical imagery by modeling sub-structure interaction and constraints

    KAUST Repository

    Sundaramoorthi, Ganesh

    2012-09-13

    This paper presents a novel medical image registration algorithm that explicitly models the physical constraints imposed by objects or sub-structures of objects that have differing material composition and border each other, which is the case in most medical registration applications. Typical medical image registration algorithms ignore these constraints and therefore are not physically viable, and to incorporate these constraints would require prior segmentation of the image into regions of differing material composition, which is a difficult problem in itself. We present a mathematical model and algorithm for incorporating these physical constraints into registration / motion and deformation estimation that does not require a segmentation of different material regions. Our algorithm is a joint estimation of different material regions and the motion/deformation within these regions. Therefore, the segmentation of different material regions is automatically provided in addition to the image registration satisfying the physical constraints. The algorithm identifies differing material regions (sub-structures or objects) as regions where the deformation has different characteristics. We demonstrate the effectiveness of our method on the analysis of cardiac MRI which includes the detection of the left ventricle boundary and its deformation. The experimental results indicate the potential of the algorithm as an assistant tool for the quantitative analysis of cardiac functions in the diagnosis of heart disease.

  16. Dynamic Analysis of Jacket Substructure for Offshore Wind Turbine Generators under Extreme Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Wen-Jeng Lai

    2016-10-01

    Full Text Available In order to develop dynamic analysis technologies regarding the design of offshore wind turbine generators (OWTGs, a special project called Offshore Code Comparison Collaboration Continuation (OC4 was conducted by IEA (International Energy Agency in 2010. A similar project named INER-OC4 has been performed by the Institute of Nuclear Energy Research (INER to develop the OWTG technologies of Taiwan. Since the jacket substructure will be applied to Taiwan OWTGs before 2020, the INER-OC4 project has been devoted to the design and analysis of jacket support structure. In this work, the preliminary result of INER-OC4 is presented. A simplified analysis procedure for jacket support structure has been proposed. Both of the NREL (National Renewable Energy Laboratory 5 MW OWTG FAST model and OC4 jacket substructure model have been built and analyzed under severe design load cases (DLCs of IEC (International Electrotechnical commission 61400-3. Simulation results of six severe DLCs are performed in this work and the results are in agreement with the requirements of API (American Petroleum Institute and NORSOK (Norwegian Petroleum Industry standards.

  17. Statistics of Dark Matter Substructure: III. Halo-to-Halo Variance

    CERN Document Server

    Jiang, Fangzhou

    2016-01-01

    We present a study of unprecedented statistical power regarding the halo-to-halo variance of dark matter substructure. Using a combination of N-body simulations and a semi-analytical model, we investigate the variance in subhalo mass fractions and subhalo occupation numbers, with an emphasis on how these statistics scale with halo formation time. We demonstrate that the subhalo mass fraction, f_sub, is mainly a function of halo formation time, with earlier forming haloes having less substructure. At fixed formation redshift, the average f_sub is virtually independent of halo mass, and the mass dependence of f_sub is therefore mainly a manifestation of more massive haloes assembling later. We compare observational constraints on f_sub from gravitational lensing to our model predictions and simulation results. Although the inferred f_sub are substantially higher than the median LCDM predictions, they fall within the 95th percentile due to halo-to-halo variance. We show that while the halo occupation distributio...

  18. The investigation of dynamic behaviour of a structure using wave-based substructuring method

    Directory of Open Access Journals (Sweden)

    Ahmad Basri Ahmad Burhani

    2017-01-01

    Full Text Available There is an increasing need for accurate, efficient and economical methods for the investigation of the dynamic behaviour of large complex structures within the engineering community. The component mode synthesis (CMS has been perceived by the community to be an attractive efficient method for the investigation. However, the method has substantial shortcomings, particularly in analysing a structure having a large number of interface degrees of freedom (DOFs between substructures. This paper puts forward a method, based upon the wave-based substructuring (WBS for the investigation of the dynamic behaviour of a structure with a large number of interface DOFs. The finite element method is used to construct the full finite element model of the structure and NASTRAN 103 is used for the normal modes analysis. A new finite element model of the structure with reduced interface DOFs is constructed based on the WBS. The measurement of the dynamic behaviour of the structure is carried out using free-free boundary conditions and an impact hammer test. The predicted results of the proposed method are then compared with those from the full finite element model and experimental counterparts. The accuracy and efficiency of the proposed method are discussed and illustrated with two different case studies.

  19. Constraining dark matter sub-structure with the dynamics of astrophysical systems

    CERN Document Server

    Gonzalez-Morales, Alma X; Aguilar, Luis A

    2012-01-01

    The accuracy of the measurements of some astrophysical dynamical systems allows to constrain the existence of incredibly small gravitational perturbations. In particular, the internal Solar System dynamics (planets, Earth-Moon) opens up the possibility, for the first time, to prove the abundance, mass and size, of dark sub-structures at the Earth vicinity. We find that adopting the standard dark matter density, its local distribution can be composed by sub-solar mass halos with no currently measurable dynamical consequences, regardless of the mini-halo fraction. On the other hand, it is possible to exclude the presence of dark streams with linear mass densities higher than $\\lambda_{\\rm st}> 10^{-10} \\Msun/\\AU$ (about the Earth mass spread along the diameter of the SS up to the Kuiper belt). In addition, we review the dynamics of wide binaries inside the dwarf spheroidal galaxies in the MW. The dynamics of such kind of binaries seem to be compatible with the presence of a huge fraction of dark sub-structure, ...

  20. deconSTRUCT: general purpose protein database search on the substructure level.

    Science.gov (United States)

    Zhang, Zong Hong; Bharatham, Kavitha; Sherman, Westley A; Mihalek, Ivana

    2010-07-01

    deconSTRUCT webserver offers an interface to a protein database search engine, usable for a general purpose detection of similar protein (sub)structures. Initially, it deconstructs the query structure into its secondary structure elements (SSEs) and reassembles the match to the target by requiring a (tunable) degree of similarity in the direction and sequential order of SSEs. Hierarchical organization and judicious use of the information about protein structure enables deconSTRUCT to achieve the sensitivity and specificity of the established search engines at orders of magnitude increased speed, without tying up irretrievably the substructure information in the form of a hash. In a post-processing step, a match on the level of the backbone atoms is constructed. The results presented to the user consist of the list of the matched SSEs, the transformation matrix for rigid superposition of the structures and several ways of visualization, both downloadable and implemented as a web-browser plug-in. The server is available at http://epsf.bmad.bii.a-star.edu.sg/struct_server.html.

  1. Effects of Dark Matter Substructures on Gravitational Lensing: Results from the Aquarius Simulations

    CERN Document Server

    Xu, D D; Wang, J; Springel, V; Gao, L; White, S D M; Frenk, C S; Jenkins, A; Li, G; Navarro, J F

    2009-01-01

    We use high-resolution Aquarius simulations of Milky Way-sized haloes in the LCDM cosmology to study the effects of dark matter substructures on gravitational lensing. Each halo is resolved with ~ 10^8 particles (at a mass resolution ~ 10^3-4 M_sun/h) within its virial radius. Subhaloes with masses larger than 10^5 M_sun/h are well resolved, an improvement of at least two orders of magnitude over previous lensing studies. We incorporate a baryonic component modelled as a Hernquist profile and account for the response of the dark matter via adiabatic contraction. We focus on the "anomalous" flux ratio problem, in particular on the violation of the cusp-caustic relation due to substructures. We find that subhaloes with masses less than ~ 10^8 M_sun/h play an important role in causing flux anomalies; such low mass subhaloes have been unresolved in previous studies. There is large scatter in the predicted flux ratios between different haloes and between different projections of the same halo. In some cases, the f...

  2. The Extraordinary Amount of Substructure in the Hubble Frontier Fields Cluster Abell 2744

    CERN Document Server

    Jauzac, M; Schwinn, J; Harvey, D; Baugh, C M; Robertson, A; Bose, S; Massey, R; Owers, M; Ebeling, H; Shan, H Y; Jullo, E; Kneib, J -P; Richard, J; Atek, H; Clément, B; Egami, E; Israel, H; Knowles, K; Limousin, M; Natarajan, P; Rexroth, M; Taylor, P; Tchernin, C

    2016-01-01

    We present a joint optical/X-ray analysis of the massive galaxy cluster Abell 2744 (z=0.308). Our strong- and weak-lensing analysis within the central region of the cluster, i.e., at R<1Mpc from the brightest cluster galaxy, reveals eight substructures, including the main core. All of these dark-matter halos are detected with a significance of at least 5sigma and feature masses ranging from 0.5 to 1.4x10^{14}Msun within R<150kpc. Merten et al. (2011) and Medezinski et al. (2016) substructures are also detected by us. We measure a slightly higher mass for the main core component than reported previously and attribute the discrepancy to the inclusion of our tightly constrained strong-lensing mass model built on Hubble Frontier Fields data. X-ray data obtained by XMM-Newton reveal four remnant cores, one of them a new detection, and three shocks. Unlike Merten et al. (2011), we find all cores to have both dark and luminous counterparts. A comparison with clusters of similar mass in the MXXL simulations yie...

  3. The Substructure of the Solar Corona Observed in the Hi-C Telescope

    Science.gov (United States)

    Winebarger, A.; Cirtain, J.; Golub, L.; DeLuca, E.; Savage, S.; Alexander, C.; Schuler, T.

    2014-01-01

    In the summer of 2012, the High-resolution Coronal Imager (Hi-C) flew aboard a NASA sounding rocket and collected the highest spatial resolution images ever obtained of the solar corona. One of the goals of the Hi-C flight was to characterize the substructure of the solar corona. We therefore calculate how the intensity scales from a low-resolution (AIA) pixels to high-resolution (Hi-C) pixels for both the dynamic events and "background" emission (meaning, the steady emission over the 5 minutes of data acquisition time). We find there is no evidence of substructure in the background corona; the intensity scales smoothly from low-resolution to high-resolution Hi-C pixels. In transient events, however, the intensity observed with Hi-C is, on average, 2.6 times larger than observed with AIA. This increase in intensity suggests that AIA is not resolving these events. This result suggests a finely structured dynamic corona embedded in a smoothly varying background.

  4. CLUMPY: Jeans analysis, $\\gamma$-ray and neutrino fluxes from dark matter (sub-)structures

    CERN Document Server

    Bonnivard, Vincent; Nezri, Emmanuel; Charbonnier, Aldée; Combet, Céline; Maurin, David

    2015-01-01

    We present an update of the CLUMPY code for the calculation of the astrophysical J-factors (from dark matter annihilation/decay) for any Galactic or extragalactic dark matter halo including substructures: the concentration-mass relationship may now be drawn from a distribution, boost factors can include several levels of substructures, and triaxiality is a new option for dark matter haloes. This new version takes advantage of the cfitsio and HEALPix libraries to propose FITS output maps using the HEALPix pixelisation scheme. Skymaps for $\\gamma$-ray and neutrino signals from generic annihilation/decay spectra are now direct outputs of CLUMPY. Smoothing by a user-defined instrumental Gaussian beam is also possible. In addition to these improvements, the main novelty is the implementation of a Jeans analysis module, to obtain dark matter density profiles from kinematic data in relaxed spherical systems (e.g., dwarf spheroidal galaxies). The code is also interfaced with the GreAT toolkit designed for Markov Chai...

  5. Statistics and implications of substructure detected in a representative sample of X-ray clusters

    CERN Document Server

    Chon, Gayoung; Smith, Graham

    2012-01-01

    We present a morphological study of 35 X-ray luminous galaxy clusters at 0.15Substructure Survey (LoCuSS), for which deep XMM-Newton observations are available. We characterise the structure of the X-ray surface brightness distribution of each cluster by measuring both their power ratios and centroid shift, and thus rank the clusters by the degree of substructure. These complementary probes give a consistent description of the cluster morphologies with some well understood exceptions. We find a remarkably tight correlation of regular morphology with the occurrence of cool cores in clusters. We also compare our measurements of X-ray morphology with measurements of the luminosity gap statistics and ellipticity of the brightest cluster galaxy (BCG). We check how our new X-ray morphological analysis maps onto cluster scaling relations, finding that (i) clusters with relatively undisturbed X-ray morphologies are on average more luminous at fixed X-ray...

  6. Probing the evolution of the substructure frequency in galaxy clusters up to z~1

    CERN Document Server

    Weißmann, A; Chon, G

    2013-01-01

    Context. Galaxy clusters are the last and largest objects to form in the standard hierarchical structure formation scenario through merging of smaller systems. The substructure frequency in the past and present epoch provides excellent means for studying the underlying cosmological model. Aims. Using X-ray observations, we study the substructure frequency as a function of redshift by quantifying and comparing the fraction of dynamically young clusters at different redshifts up to z=1.08. We are especially interested in possible biases due to the inconsistent data quality of the low-z and high-z samples. Methods. Two well-studied morphology estimators, power ratio P3/P0 and center shift w, were used to quantify the dynamical state of 129 galaxy clusters, taking into account the different observational depth and noise levels of the observations. Results. Owing to the sensitivity of P3/P0 to Poisson noise, it is essential to use datasets with similar photon statistics when studying the P3/P0-z relation. We degra...

  7. RINGED SUBSTRUCTURE AND A GAP AT 1 au IN THE NEAREST PROTOPLANETARY DISK

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Sean M.; Wilner, David J.; Bai, Xue-Ning; Öberg, Karin I.; Ricci, Luca [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Zhu, Zhaohuan [Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Peyton Hall, Princeton, NJ 08544 (United States); Birnstiel, Tilman [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Carpenter, John M. [Joint ALMA Observatory (JAO), Alonso de Cordova 3107, Vitacura-Santiago de Chile (Chile); Pérez, Laura M. [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany); Hughes, A. Meredith [Department of Astronomy, Wesleyan University, Van Vleck Observatory, 96 Foss Hill Drive, Middletown, CT 06457 (United States); Isella, Andrea, E-mail: sandrews@cfa.harvard.edu [Department of Physics and Astronomy, Rice University, 6100 Main Street, Houston, TX 77005 (United States)

    2016-04-01

    We present long baseline Atacama Large Millimeter/submillimeter Array (ALMA) observations of the 870 μm continuum emission from the nearest gas-rich protoplanetary disk, around TW Hya, that trace millimeter-sized particles down to spatial scales as small as 1 au (20 mas). These data reveal a series of concentric ring-shaped substructures in the form of bright zones and narrow dark annuli (1–6 au) with modest contrasts (5%–30%). We associate these features with concentrations of solids that have had their inward radial drift slowed or stopped, presumably at local gas pressure maxima. No significant non-axisymmetric structures are detected. Some of the observed features occur near temperatures that may be associated with the condensation fronts of major volatile species, but the relatively small brightness contrasts may also be a consequence of magnetized disk evolution (the so-called zonal flows). Other features, particularly a narrow dark annulus located only 1 au from the star, could indicate interactions between the disk and young planets. These data signal that ordered substructures on ∼au scales can be common, fundamental factors in disk evolution and that high-resolution microwave imaging can help characterize them during the epoch of planet formation.

  8. Substructure dependence of jet cross sections at HERA and determination of $\\alpha_{s}$

    CERN Document Server

    Chekanov, S; Abt, I; Adamczyk, L; Adamus, M; Adler, V; Aghuzumtsyan, G; Antonioli, P; Antonov, A; Arneodo, M; Bailey, D S; Bamberger, A; Barakbaev, A N; Barbagli, G; Barbi, M; Bari, G; Barreiro, F; Bartsch, D; Basile, M; Behrens, U; Bellagamba, L; Bellan, P M; Benen, A; Bertolin, A; Bhadra, S; Bloch, I; Bold, T; Boos, E G; Borras, K; Boscherini, D; Brock, I; Brook, N H; Brugnera, R; Brümmer, N; Bruni, A; Bruni, G; Bussey, P J; Butterworth, J M; Büttner, C; Bylsma, B; Caldwell, A; Capua, M; Cara Romeo, G; Carli, T; Carlin, R; Catterall, C D; Chiochia, V; Chwastowski, J; Ciborowski, J; Ciesielski, R; Cifarelli, Luisa; Cindolo, F; Cloth, P; Cole, J E; Collins-Tooth, C; Contin, A; Cooper-Sarkar, A M; Coppola, N; Cormack, C; Corradi, M; Corriveau, F; Costa, M; Cottrell, A; D'Agostini, Giulio; Dal Corso, F; Danilov, P; Dannheim, D; De Pasquale, S; Dementiev, R K; Derrick, M; Devenish, R C E; Dhawan, S; Dobur, D; Dolgoshein, B A; Doyle, A T; Drews, G; Durkin, L S; Dusini, S; Eisenberg, Y; Ermolov, P F; Eskreys, Andrzej; Everett, A; Ferrando, J; Ferrero, M I; Figiel, J; Filges, D; Foster, B; Foudas, C; Fourletov, S; Fourletova, J; Fricke, U; Fusayasu, T; Gabareen, A; Galas, A; Gallo, E; Garfagnini, A; Geiser, A; Genta, C; Gialas, I; Giusti, P; Gladilin, L K; Gladkov, D; Glasman, C; Gliga, S; Goers, S; Goncalo, R; González, O; Gosau, T; Göttlicher, P; Grabowska-Bold, I; Grigorescu, G; Grijpink, S; Grzelak, G; Gutsche, O; Gwenlan, C; Haas, T; Hain, W; Hall-Wilton, R; Hamatsu, R; Hamilton, J; Hanlon, S; Hart, J C; Hartmann, H; Hartner, G; Heaphy, E A; Heath, G P; Helbich, M; Heusch, C A; Hilger, E; Hillert, S; Hirose, T; Hochman, D; Holm, U; Horn, C; Iacobucci, G; Iga, Y; Inuzuka, M; Irrgang, P; Jakob, H P; Jones, T W; Kagawa, S; Kahle, B; Kaji, H; Kananov, S; Karshon, M; Karstens, F; Kataoka, M; Katkov, I I; Kcira, D; Keramidas, A; Khein, L A; Kim, J Y; Kind, O; Kisielewska, D; Kitamura, S; Koffeman, E; Kohno, T; Kooijman, P; Koop, T; Korzhavina, I A; Kotanski, A; Kötz, U; Kowal, A M; Kowal, M; Kowalski, H; Kramberger, G; Kreisel, A; Krumnack, N; Kuze, M; Kuzmin, V A; Labarga, L; Labes, H; Lainesse, J; Lammers, S; Lelas, D; Levchenko, B B; Levy, A; Li, L; Lightwood, M S; Lim, H; Lim, I T; Limentani, S; Ling, T Y; Liu, X; Löhr, B; Lohrmann, E; Loizides, J H; Long, K R; Longhin, A; Lukina, O Yu; Luzniak, P; Ma, K J; Maddox, E; Magill, S; Mankel, R; Margotti, A; Marini, G; Martin, J F; Mastroberardino, A; Matsuzawa, K; Mattingly, M C K; McCubbin, N A; Melzer-Pellmann, I A; Menary, S R; Metlica, F; Meyer, U; Miglioranzi, S; Milite, M; Mirea, A; Monaco, V; Montanari, A; Musgrave, B; Nagano, K; Namsoo, T; Nania, R; Nguyen, C N; Nigro, A; Ning, Y; Notz, D; Nowak, R J; Nuncio, A E; Oh, B Y; Olkiewicz, K; Pac, M Y; Padhi, S; Palmonari, F; Parenti, A; Park, I H; Patel, S; Paul, E; Pavel, Usan; Pawlak, J M; Pelfer, P G; Pellegrino, A; Pesci, A; Piotrzkowski, K; Plucinsky, P P; Pokrovskiy, N S; Polini, A; Posocco, M; Proskuryakov, A S; Przybycien, M B; Rautenberg, J; Raval, A; Reeder, D D; Ren, Z; Renner, R; Repond, J; Rinaldi, L; Riveline, U; Robins, S; Rosin, M; Ruspa, M; Ryan, P; Sacchi, R; Salehi, H; Sartorelli, G; Savin, A A; Saxon, D H; Schagen, S; Schioppa, M; Schlenstedt, S; Schleper, P; Schmidke, W B; Schneekloth, U; Schörner-Sadenius, T; Sciulli, F; Shcheglova, L M; Skillicorn, I O; Slominski, W; Smith, W H; Soares, M; Solano, A; Son, D; Sosnovtsev, V V; Stairs, D G; Stanco, L; Standage, J; Stifutkin, A; Stonjek, S; Stopa, P; Stösslein, U; Straub, P B; Suchkov, S; Susinno, G; Suszycki, L; Sutiak, J; Sutton, M R; Sztuk, J; Szuba, D; Szuba, J; Tandler, J; Tapper, A D; Targett-Adams, C; Tassi, E; Tawara, T; Terron, J; Tiecke, H G; Tokushuku, K; Tsurugai, T; Turcato, M; Tymieniecka, T; Ukleja, A; Ukleja, J; Vázquez, M; Vlasov, N N; Voss, K C; Walczak, R; Walsh, R; Wang, M; Whitmore, J J; Wichmann, K; Wick, K; Wiggers, L; Wills, H H; Wing, M; Wolf, G; Yamada, S; Yamashita, T; Yamazaki, Y; Yoshida, R; Youngman, C; Zambrana, M; Zawiejski, L; Zeuner, W; Zhautykov, B O; Zichichi, A; Ziegler, A; Zotkin, S A; De Favereau, J; De Wolf, E; Del Peso, J

    2004-01-01

    Jet substructure and differential cross sections for jets produced in the photoproduction and deep inelastic ep scattering regimes have been measured with the ZEUS detector at HERA using an integrated luminosity of 82.2 pb-1. The substructure of jets has been studied in terms of the jet shape and subjet multiplicity for jets with transverse energies Et(jet) > 17 GeV. The data are well described by the QCD calculations. The jet shape and subjet multiplicity are used to tag gluon- and quark-initiated jets. Jet cross sections as functions of Et(jet), jet pseudorapidity, the jet-jet scattering angle, dijet invariant mass and the fraction of the photon energy carried by the dijet system are presented for gluon- and quark-tagged jets. The data exhibit the behaviour expected from the underlying parton dynamics. A value of alphas(Mz) of alphas(Mz) = 0.1176 +-0.0009(stat.) -0.0026 +0.0009 (exp.) -0.0072 +0.0091 (th.) was extracted from the measurements of jet shapes in deep inelastic scattering.

  9. A Synoptic Map of Halo Substructures from the Pan-STARRS1 3π Survey

    Science.gov (United States)

    Bernard, Edouard J.; Ferguson, Annette M. N.; Schlafly, Edward F.; Martin, Nicolas F.; Rix, Hans-Walter; Bell, Eric F.; Finkbeiner, Douglas P.; Goldman, Bertrand; Martínez-Delgado, David; Sesar, Branimir; Wyse, Rosemary F. G.; Burgett, William S.; Chambers, Kenneth C.; Draper, Peter W.; Hodapp, Klaus W.; Kaiser, Nicholas; Kudritzki, Rolf-Peter; Magnier, Eugene A.; Metcalfe, Nigel; Wainscoat, Richard J.; Waters, Christopher

    2016-08-01

    We present a panoramic map of the entire Milky Way halo north of δ ˜ -30° (˜ 30,000 deg2), constructed by applying the matched-filter technique to the Pan-STARRS1 3π Survey dataset. Using single-epoch photometry reaching to g ˜22, we are sensitive to stellar substructures with heliocentric distances between 3.5 and ˜35 kpc. We recover almost all previously-reported streams in this volume and demonstrate that several of these are significantly more extended than earlier datasets have indicated. In addition, we also report five new candidate stellar streams. One of these features appears significantly broader and more luminous than the others and is likely the remnant of a dwarf galaxy. The other four streams are consistent with a globular cluster origin, and three of these are rather short in projection (≲ 10°), suggesting that streams like Ophiuchus may not be that rare. Finally, a significant number of more marginal substructures are also revealed by our analysis; many of these features can also be discerned in matched-filter maps produced by other authors from SDSS data, and hence they are very likely to be genuine. However, the extant 3π data is currently too shallow to determine their properties or produce convincing CMDs. The global view of the Milky Way provided by Pan-STARRS1 provides further evidence for the important role of both globular cluster disruption and dwarf galaxy accretion in building the Milky Way's stellar halo.

  10. Gamma-rays from dark matter annihilations strongly constrain the substructure in halos

    CERN Document Server

    Pinzke, Anders; Bergstrom, Lars

    2009-01-01

    Recently, it has been shown that electrons and positrons from dark matter (DM) annihilations provide an excellent fit to the Fermi, PAMELA, and HESS data. Using this DM model, which requires an enhancement of the annihilation cross section over its standard value to match the observations, we show that it immediately implies an observable level of gamma-ray emission for the Fermi telescope from nearby galaxy clusters such as Virgo and Fornax. We show that this DM model implies a peculiar feature from final state radiation that is a distinctive signature of DM. Using the EGRET upper limit on the gamma-ray emission from Virgo, we constrain the minimum mass of substructures within DM halos to be > 0.1 M_sol - five orders of magnitudes larger than the expectation for cold dark matter. This limits the cutoff scale in the linear matter power spectrum to k 10^4 M_sol: if the true substructure cutoff is much smaller than this, the DM interpretation of the Fermi/PAMELA/HESS data must be wrong. To address the problem ...

  11. Disk Evolution and Bar Triggering Driven by Interactions with Dark Matter Substructure

    CERN Document Server

    Romano-Diaz, Emilio; Heller, Clayton; Hoffman, Yehuda

    2008-01-01

    We study formation and evolution of bar-disk systems in fully self-consistent cosmological simulations of galaxy formation in the LCDM WMAP3 Universe. In a representative model we find that the first generation of bars form in response to the asymmetric dark matter (DM) distribution (i.e., DM filament) and quickly decay. Subsequent bar generations form and are destroyed during the major merger epoch permeated by interactions with a DM substructure (subhalos). A long-lived bar is triggered by a tide from a subhalo and survives for ~10 Gyr. The evolution of this bar is followed during the subsequent numerous minor mergers and interactions with the substructure. Together with intrinsic factors, these interactions largely determine the stellar bar evolution. The bar strength and its pattern speed anticorrelate, except during interactions and when the secondary (nuclear) bar is present. For about 5 Gyr bar pattern speed increases substantially despite the loss of angular momentum to stars and cuspy DM halo. We ana...

  12. A Synoptic Map of Halo Substructures from the Pan-STARRS1 3\\pi\\ Survey

    CERN Document Server

    Bernard, Edouard J; Schlafly, Edward F; Martin, Nicolas F; Rix, Hans-Walter; Bell, Eric F; Finkbeiner, Douglas P; Goldman, Bertrand; Martinez-Delgado, David; Sesar, Branimir; Wyse, Rosemary F G; Burgett, William S; Chambers, Kenneth C; Draper, Peter W; Hodapp, Klaus W; Kudritzki, Rolf-Peter; Magnier, Eugene A; Metcalfe, Nigel; Wainscoat, Richard J; Waters, Christopher

    2016-01-01

    We present a panoramic map of the entire Milky Way halo north of dec~-30 degrees (~30,000 deg^2), constructed by applying the matched-filter technique to the Pan-STARRS1 3Pi Survey dataset. Using single-epoch photometry reaching to g~22, we are sensitive to stellar substructures with heliocentric distances between 3.5 and ~35 kpc. We recover almost all previously-reported streams in this volume and demonstrate that several of these are significantly more extended than earlier datasets have indicated. In addition, we also report five new candidate stellar streams. One of these features appears significantly broader and more luminous than the others and is likely the remnant of a dwarf galaxy. The other four streams are consistent with a globular cluster origin, and three of these are rather short in projection (<10 degrees), suggesting that streams like Ophiuchus may not be that rare. Finally, a significant number of more marginal substructures are also revealed by our analysis; many of these features can a...

  13. A Radio for Hidden-Photon Dark Matter Detection

    CERN Document Server

    Chaudhuri, Saptarshi; Irwin, Kent; Mardon, Jeremy; Rajendran, Surjeet; Zhao, Yue

    2014-01-01

    We propose a resonant electromagnetic detector to search for hidden-photon dark matter over an extensive range of masses. Hidden-photon dark matter can be described as a weakly coupled "hidden electric field," oscillating at a frequency fixed by the mass, and able to penetrate any shielding. At low frequencies (compared to the inverse size of the shielding), we find that observable effect of the hidden photon inside any shielding is a real, oscillating magnetic field. We outline experimental setups designed to search for hidden-photon dark matter, using a tunable, resonant LC circuit designed to couple to this magnetic field. Our "straw man" setups take into consideration resonator design, readout architecture and noise estimates. At high frequencies,there is an upper limit to the useful size of a single resonator set by $1/\

  14. Secluded Dark Matter Coupled to a Hidden CFT

    CERN Document Server

    von Harling, Benedict

    2012-01-01

    Models of secluded dark matter offer a variant on the standard WIMP picture and can modify our expectations for hidden sector phenomenology and detection. In this work we extend a minimal model of secluded dark matter, comprised of a U(1)'-charged dark matter candidate, to include a confining hidden-sector CFT. This provides a technically natural explanation for the hierarchically small mediator-scale, with hidden-sector confinement generating m_{gamma'}>0. Furthermore, the thermal history of the universe can differ markedly from the WIMP picture due to (i) new annihilation channels, (ii) a (potentially) large number of hidden-sector degrees of freedom, and (iii) a hidden-sector phase transition at temperatures T << M_{dm} after freeze out. The mediator allows both the dark matter and the Standard Model to communicate with the CFT, thus modifying the low-energy phenomenology and cosmic-ray signals from the secluded sector.

  15. Abelian Hidden Sectors at a GeV

    Energy Technology Data Exchange (ETDEWEB)

    Morrissey, David E.; Poland, David; /Harvard U.; Zurek, Kathryn; /Fermilab /Michigan U.

    2009-04-16

    We discuss mechanisms for naturally generating GeV-scale hidden sectors in the context of weak-scale supersymmetry. Such low mass scales can arise when hidden sectors are more weakly coupled to supersymmetry breaking than the visible sector, as happens when supersymmetry breaking is communicated to the visible sector by gauge interactions under which the hidden sector is uncharged, or if the hidden sector is sequestered from gravity-mediated supersymmetry breaking. We study these mechanisms in detail in the context of gauge and gaugino mediation, and present specific models of Abelian GeV-scale hidden sectors. In particular, we discuss kinetic mixing of a U(1){sub x} gauge force with hypercharge, singlets or bi-fundamentals which couple to both sectors, and additional loop effects. Finally, we investigate the possible relevance of such sectors for dark matter phenomenology, as well as for low- and high-energy collider searches.

  16. HIDDEN WEB EXTRACTOR DYNAMIC WAY TO UNCOVER THE DEEP WEB

    Directory of Open Access Journals (Sweden)

    DR. ANURADHA

    2012-06-01

    Full Text Available In this era of digital tsunami of information on the web, everyone is completely dependent on the WWW for information retrieval. This has posed a challenging problem in extracting relevant data. Traditional web crawlers focus only on the surface web while the deep web keeps expanding behind the scene. The web databases are hidden behind the query interfaces. In this paper, we propose a Hidden Web Extractor (HWE that can automatically discover and download data from the Hidden Web databases. Since the only “entry point” to a Hidden Web site is a query interface, the main challenge that a Hidden WebExtractor has to face is how to automatically generate meaningful queries for the unlimited number of website pages.

  17. Gauge Coupling Unification with Hidden Photon, and Minicharged Dark Matter

    CERN Document Server

    Daido, Ryuji; Yokozaki, Norimi

    2016-01-01

    We show that gauge coupling unification is realized with a greater accuracy in the presence of a massless hidden photon which has a large kinetic mixing with hypercharge. We solve the renormalization group equations at two-loop level and find that the GUT unification scale is around $10^{16.5}$ GeV which sufficiently suppresses the proton decay rate, and that the unification depends only on the kinetic mixing, but not on the hidden gauge coupling nor the presence of vector-like matter fields charged under U(1)$_H$ and/or SU(5). Matter fields charged under the unbroken hidden U(1)$_H$ are stable and they contribute to dark matter. Interestingly, they become minicharged dark matter which carries a small but non-zero electric charge, if the hidden gauge coupling is tiny. The minicharged dark matter is a natural outcome of the gauge coupling unification with a hidden photon.

  18. A Hidden-Removal Model of Dam Perspective Drawing

    Institute of Scientific and Technical Information of China (English)

    WANG Zi-ru; ZHOU Hui-cheng; LI Ming-qiu

    2011-01-01

    Aming at water conservancy project visualization, a hidden-removal method of dam perspective drawings is realized by building a hidden-removal mathematical model for overlapping points location to set up the hidden relationship among point and plane, plane and plane in space. On this basis, as an example of panel rockfill dam, a dam hidden-removal perspective drawing is generated in different directions and different visual angles through adapting VC++ and OpenGL visualizing technology. The results show that the data construction of the model is simple which can overcome the disadvantages of considerable and complicated calculation. This method also provides the new means to draw hidden-removal perspective drawings for those landforms and ground objects.

  19. Magneto-Radar Hidden Metal Detector

    Energy Technology Data Exchange (ETDEWEB)

    McEwan, Thomas E. (Las Vegas, NV)

    2005-07-05

    A varying magnetic field excites slight vibrations in an object and a radar sensor detects the vibrations at a harmonic of the excitation frequency. The synergy of the magnetic excitation and radar detection provides increased detection range compared to conventional magnetic metal detectors. The radar rejects background clutter by responding only to reflecting objects that are vibrating at a harmonic excitation field, thereby significantly improving detection reliability. As an exemplary arrangement, an ultra-wideband micropower impulse radar (MIR) is capable of being employed to provide superior materials penetration while providing range information. The magneto-radar may be applied to pre-screening magnetic resonance imaging (MRI) patients, landmine detection and finding hidden treasures.

  20. Effect of Noise on hidden data

    Directory of Open Access Journals (Sweden)

    Garima Tomar

    2012-02-01

    Full Text Available This paper simulates an effective data hiding technique i.e. steganography based on LSB insertion and RSA encryption in order to provide seven million times better security than the previous work. The Main idea of proposed scheme is to encrypt secret data by RSA 1024 algorithm, convert it in to binary sequence bit and then embedded into each cover pixels by modifying the least significant bits (LSBs of cover pixels. The result image is also known as steganography image. The PSNR value of this steganography image is 54.34 db. In this paper Baboon image is used for experimental purpous.This steganography image is transmitted through AWGN channel, and performance is simulated. The image and hidden data are reconstructed with the SNR level ≥9 dB.

  1. Sending Hidden Data via Google Suggest

    CERN Document Server

    Bialczak, Piotr; Szczypiorski, Krzysztof

    2011-01-01

    Google Suggest is a service incorporated within Google Web Search which was created to help user find the right search phrase by proposing the autocompleting popular phrases while typing. The paper presents a new network steganography method called StegSuggest which utilizes suggestions generated by Google Suggest as a hidden data carrier. The detailed description of the method's idea is backed up with the analysis of the network traffic generated by the Google Suggest to prove its feasibility. The traffic analysis was also performed to discover the occurrence of two TCP options: Window Scale and Timestamp which StegSuggest uses to operate. Estimation of method steganographic bandwidth proves that it is possible to insert 100 bits of steganogram into every suggestions list sent by Google Suggest service.

  2. Grand unified hidden-sector dark matter

    Science.gov (United States)

    Lonsdale, Stephen J.; Volkas, Raymond R.

    2014-10-01

    We explore G×G unified theories with the visible and the hidden or dark sectors paired under a Z2 symmetry. Developing a system of "asymmetric symmetry breaking" we motivate such models on the basis of their ability to generate dark baryons that are confined with a mass scale just above that of the proton, as motivated by asymmetric dark matter. This difference is achieved from the distinct but related confinement scales that develop in unified theories that have the two factors of G spontaneously breaking in an asymmetric manner. We show how Higgs potentials that admit different gauge group breaking chains in each sector can be constructed, and demonstrate the capacity for generating different fermion mass scales. Lastly we discuss supersymmetric extensions of such schemes.

  3. Hidden caries’ challenge diagnosis: case report

    Directory of Open Access Journals (Sweden)

    Fernanda Mara de Paiva Bertoli

    2013-06-01

    Full Text Available Introduction: Hidden caries is a term used to describe occlusal dentine caries that is missed on a visual examination, but is large and demineralised enough to be detected by another exam for example, radiographs. Case report: This article reports a case of large dentine caries, which presented as to be a small pit-and-fissure carious lesion on the occlusal surface of the right mandibular permanent first molar in a 10-year-old girl. The treatment included root canal treatment and the sealing of the cavity with composite resin. Conclusion: Careful visual examination, with cleaning and drying of teeth, associated to bitewing radiographs may improve occlusal caries detection. Dentists should examine bitewing radiographs carefully for proximal caries and occlusal demineralization. Radiographs are an effective method of caries diagnosis that can avoid large destruction and allows less invasive treatment.

  4. Hidden expectations within the Danish VET system

    DEFF Research Database (Denmark)

    Hjort-Madsen, Peder

    Researching the pressing retention and dropout problems of the Danish VET system (app. 20 pct. of a year group never achieve an upper secondary education) this paper takes its point of departure in the hypothesis that low performing students are kept in a marginal position (at the risk of dropping...... out) within the VET system, because of hidden expectations related to e.g. individualized responsibility, a certain student behavior (sitting still, participating actively), etc. By approaching the VET system as a cultural context (cultural praxis) the subtle reproductive mechanisms of the VET system...... are shown. With empirical examples from different introductory VET courses, it is shown how the school, the teachers and the students themselves are reproducing poor school performance and student background – being it gendered, ethnical or social – and hereby proving to the students, that school...

  5. Hidden expectations within the Danish VET system

    DEFF Research Database (Denmark)

    Hjort-Madsen, Peder

    2011-01-01

    Researching the pressing retention and dropout problems of the Danish VET system (app. 20 pct. of a year group never achieve an upper secondary education) this paper takes its point of departure in the hypothesis that low performing students are kept in a marginal position (at the risk of dropping...... out) within the VET system, because of hidden expectations related to e.g. individualized responsibility, a certain student behavior (sitting still, participating actively), etc. By approaching the VET system as a cultural context (cultural praxis) the subtle reproductive mechanisms of the VET system...... are shown. With empirical examples from different introductory VET courses, it is shown how the school, the teachers and the students themselves are reproducing poor school performance and student background – being it gendered, ethnical or social – and hereby proving to the students, that school...

  6. Nuclear scissors modes and hidden angular momenta

    CERN Document Server

    Balbutsev, E B; Schuck, P

    2016-01-01

    The coupled dynamics of low lying modes and various giant resonances are studied with the help of the Wigner Function Moments method generalized to take into account spin degrees of freedom and pair correlations simultaneously. The method is based on Time Dependent Hartree-Fock-Bogoliubov equations. The model of the harmonic oscillator including spin-orbit potential plus quadrupole-quadrupole and spin-spin interactions is considered. New low lying spin dependent modes are analyzed. Special attention is paid to the scissors modes. A new source of nuclear magnetism, connected with counter-rotation of spins up and down around the symmetry axis (hidden angular momenta), is discovered. Its inclusion into the theory allows one to improve substantially the agreement with experimental data in the description of energies and transition probabilities of scissors modes.

  7. Hidden expectations within the Danish VET system

    DEFF Research Database (Denmark)

    Hjort-Madsen, Peder

    2011-01-01

    out) within the VET system, because of hidden expectations related to e.g. individualized responsibility, a certain student behavior (sitting still, participating actively), etc. By approaching the VET system as a cultural context (cultural praxis) the subtle reproductive mechanisms of the VET system...... are shown. With empirical examples from different introductory VET courses, it is shown how the school, the teachers and the students themselves are reproducing poor school performance and student background – being it gendered, ethnical or social – and hereby proving to the students, that school......Researching the pressing retention and dropout problems of the Danish VET system (app. 20 pct. of a year group never achieve an upper secondary education) this paper takes its point of departure in the hypothesis that low performing students are kept in a marginal position (at the risk of dropping...

  8. Hidden baryons: The physics of Compton composites

    Science.gov (United States)

    Mayer, Frederick J.

    2016-06-01

    A large fraction of the mass-energy of the Universe appears to be composed of Compton composites. How is it then that these composites are not frequently observed in experiments? This paper addresses this question, and others, by reviewing recent publications that: 1) introduced Compton composites, 2) showed how and where they are formed and 3) explained how they interact with other systems. Though ubiquitous in many physical situations, Compton composites are almost completely hidden in experiments due to their unique interaction characteristics. Still, their presence has been indirectly observed, though not interpreted as such until recently. Looking to the future, direct-detection experiments are proposed that could verify the composites' components. It is with deep sadness that I dedicate this paper to my mentor, collaborator, and friend, Dr. John R. Reitz, who passed away within days of the publication of our paper “Compton Composites Late in the Early Universe”.

  9. Hidden realities inside PBL design processes

    DEFF Research Database (Denmark)

    Pihl, Ole Verner

    2015-01-01

    Design Process, but is a group-based architecture and design education better than that which is individually based? How does PBL affect space, form, and creative processes? Hans Kiib, professor and one of the founders of the Department of Architecture and Design in Aalborg, describes his intentions...... within the group work, as it is closer related to the actual PBL process”. Is the Integrated Design Process (Knudstrup 2004) and is Colb (1975) still current and valid? Can we still use these methodologies when we must create “learning for an unknown future,” as Ronald Barnett (2004) claims that we...... investigates the creative processes of the collective and the individual and clarifies some of the hidden realities behind the PBL-based creative processes, both through an inquiry with the students and a more methodological and theoretical approach. The paper also explores how to integrate artistic...

  10. Aluminium Diphosphamethanides: Hidden Frustrated Lewis Pairs.

    Science.gov (United States)

    Styra, Steffen; Radius, Michael; Moos, Eric; Bihlmeier, Angela; Breher, Frank

    2016-07-04

    The synthesis and characterisation of two aluminium diphosphamethanide complexes, [Al(tBu)2 {κ(2) P,P'-Mes*PCHPMes*}] (3) and [Al(C6 F5 )2 {κ(2) P,P'-Mes*PCHPMes*}] (4), and the silylated analogue, Mes*PCHP(SiMe3 )Mes* (5), are reported. The aluminium complexes feature four-membered PCPAl core structures consisting of diphosphaallyl ligands. The silylated phosphine 5 was found to be a valuable precursor for the synthesis of 4 as it cleanly reacts with the diaryl aluminium chloride [(C6 F5 )2 AlCl]2 . The aluminium complex 3 reacts with molecular dihydrogen at room temperature under formation of the acyclic σ(2) λ(3) ,σ(3) λ(3) -diphosphine Mes*PCHP(H)Mes* and the corresponding dialkyl aluminium hydride [tBu2 AlH]3 . Thus, 3 belongs to the family of so-called hidden frustrated Lewis pairs.

  11. Wavelet domain hidden markovian bayesian document segmentation

    Institute of Scientific and Technical Information of China (English)

    Sun Junxi; Xiao Changyan; Zhang Su; Chen Yazhu

    2005-01-01

    A novel algorithm for Bayesian document segmentation is proposed based on the wavelet domain hidden Markov tree (HMT) model. Once the parameters of model are known, according to the sequential maximum a posterior probability (SMAP) rule, firstly, the likelihood probability of HMT model for each pattern is computed from fine to coarse procedure. Then, the interscale state transition probability is solved using Expectation Maximum (EM) algorithm based on hybrid-quadtree and multiscale context information is fused from coarse to fine procedure. In order to get pixellevel segmentation, the redundant wavelet domain Gaussian mixture model (GMM) is employed to formulate pixel-level statistical property. The experiment results show that the proposed scheme is feasible and robust.

  12. The Detection of Hidden Periodicities in EEG

    Institute of Scientific and Technical Information of China (English)

    YOU Rong-yi

    2007-01-01

    Abstract.A novel method for detecting the hidden periodicities in EEG is proposed.By using a width-varying window in the time domain, the structure function of EEG time series is defined. It is found that the minima of the structure function, within a finite window width, can be found regularly, which indicate that there are some certain periodicities associated with EEG time series. Based on the structure function, a further quadratic structure function of EEG time series is defined. By quadratic structure function, it can be seen that the periodicities of EEG become more obvious, moreover, the period of EEG can be determined accurately. These results will be meaningful for studying the neuron activity inside the human brain.

  13. Hidden fungi, emergent properties: endophytes and microbiomes.

    Science.gov (United States)

    Porras-Alfaro, Andrea; Bayman, Paul

    2011-01-01

    Endophytes are microorganisms that live within plant tissues without causing symptoms of disease. They are important components of plant microbiomes. Endophytes interact with, and overlap in function with, other core microbial groups that colonize plant tissues, e.g., mycorrhizal fungi, pathogens, epiphytes, and saprotrophs. Some fungal endophytes affect plant growth and plant responses to pathogens, herbivores, and environmental change; others produce useful or interesting secondary metabolites. Here, we focus on new techniques and approaches that can provide an integrative understanding of the role of fungal endophytes in the plant microbiome. Clavicipitaceous endophytes of grasses are not considered because they have unique properties distinct from other endophytes. Hidden from view and often overlooked, endophytes are emerging as their diversity, importance for plant growth and survival, and interactions with other organisms are revealed.

  14. A New Hidden Web Crawling Approach

    Directory of Open Access Journals (Sweden)

    L.Saoudi

    2015-10-01

    Full Text Available Traditional search engines deal with the Surface Web which is a set of Web pages directly accessible through hyperlinks and ignores a large part of the Web called hidden Web which is a great amount of valuable information of online database which is “hidden” behind the query forms. To access to those information the crawler have to fill the forms with a valid data, for this reason we propose a new approach which use SQLI technique in order to find the most promising keywords of a specific domain for automatic form submission. The effectiveness of proposed framework has been evaluated through experiments using real web sites and encouraging preliminary results were obtained

  15. Probabilistic Resilience in Hidden Markov Models

    Science.gov (United States)

    Panerati, Jacopo; Beltrame, Giovanni; Schwind, Nicolas; Zeltner, Stefan; Inoue, Katsumi

    2016-05-01

    Originally defined in the context of ecological systems and environmental sciences, resilience has grown to be a property of major interest for the design and analysis of many other complex systems: resilient networks and robotics systems other the desirable capability of absorbing disruption and transforming in response to external shocks, while still providing the services they were designed for. Starting from an existing formalization of resilience for constraint-based systems, we develop a probabilistic framework based on hidden Markov models. In doing so, we introduce two new important features: stochastic evolution and partial observability. Using our framework, we formalize a methodology for the evaluation of probabilities associated with generic properties, we describe an efficient algorithm for the computation of its essential inference step, and show that its complexity is comparable to other state-of-the-art inference algorithms.

  16. Identifying Exotic Hidden-Charm Pentaquarks.

    Science.gov (United States)

    Chen, Rui; Liu, Xiang; Li, Xue-Qian; Zhu, Shi-Lin

    2015-09-25

    The LHCb Collaboration at the Large Hadron Collider at CERN discovered two pentaquark states P_{c}(4380) and P_{c}(4450). These two hidden-charm states are interpreted as the loosely bound Σ_{c}(2455)D^{*} and Σ_{c}^{*}(2520)D^{*} molecular states in the boson exchange interaction model, which provides an explanation for why the experimental width of P_{c}(4450) is much narrower than that of P_{c}(4380). The discovery of the new resonances P_{c}(4380) and P_{c}(4450), indeed, opens a new page for hadron physics. The partners of P_{c}(4380) and P_{c}(4450) should be pursued in future experiments.

  17. Using HPGe detector for a solar hidden-photons search

    CERN Document Server

    Horvat, R; Krcmar, M; Krecak, Z; Ljubicic, A

    2012-01-01

    In this paper we report on the results of our search for photons from a U(1) gauge factor in the hidden sector of the full theory, by observing the single spectrum in a HPGe detector arising as a result of the photoelectric-like absorption of hidden photons emitted from the Sun on germanium atoms inside the detector. The main ingredient of the theory used in our analysis, a severely constrained kinetic mixing from the two U(1) gauge factors and massive hidden photons, leads to both photon into hidden states oscillations and to a minuscule coupling of hidden photons to visible matter, of which the latter our experimental setup has been designed to observe. On a theoretical side, full account was taken of the effects of refraction and damping of photons while propagating in the Sun's interior. We exclude hidden photons with kinetic couplings chi > (1.5x10^{-6}-2.6x10^{-11}) for the mass region 1.7x10^{-4} eV < m_\\gamma' < 3.4 eV. Our constraints on the mixing parameter chi at sub-eV hidden-photon masses p...

  18. Hidden photon dark matter search with large metallic mirror

    Energy Technology Data Exchange (ETDEWEB)

    Doebrich, Babette; Lindner, Axel [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Daumiller, Kai; Engel, Ralph; Roth, Markus [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany); Kowalski, Marek [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Redondo, Javier [Zaragoza Univ. (Spain)

    2014-10-15

    If Dark Matter is composed of hidden-sector photons that kinetically mix with photons of the visible sector, then Dark Matter has a tiny oscillating electric field component. Its presence would lead to a small amount of visible radiation being emitted from a conducting surface, with the photon frequency given approximately by the mass of the hidden photon. Here, we report on experimental efforts that have started recently to search for such hidden photon Dark Matter in the (sub-)eV regime with a prototype mirror for the Auger fluorescence detector at the Karlsruhe Institute for Technology.

  19. Suppressing the QCD axion abundance by hidden monopoles

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, Masahiro [Tokyo Univ., Chiba (Japan). Inst. for Cosmic Ray Research; Tokyo Univ., Chiba (Japan). Kavli IPMU (WPI), UTIAS; Takahashi, Fuminobu [Tokyo Univ., Miyagi (Japan). Dept. of Physics; Tokyo Univ., Chiba (Japan). Kavli IPMU (WPI), UTIAS; Yamada, Masaki [Tokyo Univ., Chiba (Japan). Inst. for Cosmic Ray Research; Tokyo Univ., Chiba (Japan). Kavli IPMU (WPI), UTIAS; DESY Hamburg (Germany)

    2015-11-15

    We study the Witten effect of hidden monopoles on the QCD axion dynamics, and show that its abundance as well as isocurvature perturbations can be significantly suppressed if there is a sufficient amount of hidden monopoles. When the hidden monopoles make up a significant fraction of dark matter, the Witten effect suppresses the abundance of axion with the decay constant smaller than 10{sup 12} GeV. The cosmological domain wall problem of the QCD axion can also be avoided, relaxing the upper bound on the decay constant when the Peccei-Quinn symmetry is spontaneously broken after inflation.

  20. Suppressing the QCD axion abundance by hidden monopoles

    Directory of Open Access Journals (Sweden)

    Masahiro Kawasaki

    2016-02-01

    Full Text Available We study the Witten effect of hidden monopoles on the QCD axion dynamics, and show that its abundance as well as isocurvature perturbations can be significantly suppressed if there is a sufficient amount of hidden monopoles. When the hidden monopoles make up a significant fraction of dark matter, the Witten effect suppresses the abundance of axion with the decay constant smaller than 1012GeV. The cosmological domain wall problem of the QCD axion can also be avoided, relaxing the upper bound on the decay constant when the Peccei–Quinn symmetry is spontaneously broken after inflation.