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Sample records for order independent similarity

  1. Ordered Self-Similar Patterns in Anisotropic Stochastic Growth.

    PubMed

    Yao, Zhenwei; Olvera de la Cruz, Monica

    2016-07-07

    We propose an anisotropic stochastic growth model to rationalize the anisotropic self-assembly of supramolecules to form elongated two-dimensional ribbon structures in a recent experiment. The model exhibits distinct growth scenarios that are critically controlled by the ratio of the transverse and the longitudinal growth rate. In the regime of suppressed transverse growth, the model generates the experimentally observed elongated structures through layer-by-layer growing. We further observe the convergence of rough clusters toward smooth regular elliptic patterns by averaging over a number of independent growth processes. Remarkably, these resulting elliptic clusters are self-similar in each instantaneous moment in the growth process. Statistical analysis suggests that the realization of such ordered patterns does not rely on the delicate coordination of different parts in the cluster growth. The self-similarity phenomenon derived from this idealized model may have wider implications, notably in the designed clustering of various elementary building blocks with anisotropic interactions.

  2. Similar Situations? Special Needs in Different Groups of Independent Schools

    ERIC Educational Resources Information Center

    Magnússon, Gunnlaugur; Göransson, Kerstin; Nilholm, Claes

    2015-01-01

    This study explores differences between different groups of Swedish independent schools' work with pupils in need of special support (PNSS). Data comes from a total population study of independent schools. Data is analyzed using six categories of profile that may affect the special educational values at the schools, and therefore the situation for…

  3. Self-similarity of higher-order moving averages

    NASA Astrophysics Data System (ADS)

    Arianos, Sergio; Carbone, Anna; Türk, Christian

    2011-10-01

    In this work, higher-order moving average polynomials are defined by straightforward generalization of the standard moving average. The self-similarity of the polynomials is analyzed for fractional Brownian series and quantified in terms of the Hurst exponent H by using the detrending moving average method. We prove that the exponent H of the fractional Brownian series and of the detrending moving average variance asymptotically agree for the first-order polynomial. Such asymptotic values are compared with the results obtained by the simulations. The higher-order polynomials correspond to trend estimates at shorter time scales as the degree of the polynomial increases. Importantly, the increase of polynomial degree does not require to change the moving average window. Thus trends at different time scales can be obtained on data sets with the same size. These polynomials could be interesting for those applications relying on trend estimates over different time horizons (financial markets) or on filtering at different frequencies (image analysis).

  4. Driven similarity renormalization group: Third-order multireference perturbation theory

    NASA Astrophysics Data System (ADS)

    Li, Chenyang; Evangelista, Francesco A.

    2017-03-01

    A third-order multireference perturbation theory based on the driven similarity renormalization group (DSRG-MRPT3) approach is presented. The DSRG-MRPT3 method has several appealing features: (a) it is intruder free, (b) it is size consistent, (c) it leads to a non-iterative algorithm with O (N6) scaling, and (d) it includes reference relaxation effects. The DSRG-MRPT3 scheme is benchmarked on the potential energy curves of F2, H2O2 , C2H6 , and N2 along the F-F, O-O, C-C, and N-N bond dissociation coordinates, respectively. The nonparallelism errors of DSRG-MRPT3 are consistent with those of complete active space third-order perturbation theory and multireference configuration interaction with singles and doubles and show significant improvements over those obtained from DSRG second-order multireference perturbation theory. Our efficient implementation of the DSRG-MRPT3 based on factorized electron repulsion integrals enables studies of medium-sized open-shell organic compounds. This point is demonstrated with computations of the singlet-triplet splitting (ΔST=ET-ES ) of 9,10-anthracyne. At the DSRG-MRPT3 level of theory, our best estimate of the adiabatic ΔST is 3.9 kcal mol-1, a value that is within 0.1 kcal mol-1 from multireference coupled cluster results.

  5. Driven similarity renormalization group: Third-order multireference perturbation theory

    DOE PAGES

    Li, Chenyang; Evangelista, Francesco A.

    2017-03-28

    Here, a third-order multireference perturbation theory based on the driven similarity renormalization group (DSRG-MRPT3) approach is presented. The DSRG-MRPT3 method has several appealing features: (a) it is intruder free, (b) it is size consistent, (c) it leads to a non-iterative algorithm with O(N6) scaling, and (d) it includes reference relaxation effects. The DSRG-MRPT3 scheme is benchmarked on the potential energy curves of F2, H2O2, C2H6, and N2 along the F–F, O–O, C–C, and N–N bond dissociation coordinates, respectively. The nonparallelism errors of DSRG-MRPT3 are consistent with those of complete active space third-order perturbation theory and multireference configuration interaction with singlesmore » and doubles and show significant improvements over those obtained from DSRG second-order multireference perturbation theory. Our efficient implementation of the DSRG-MRPT3 based on factorized electron repulsion integrals enables studies of medium-sized open-shell organic compounds. This point is demonstrated with computations of the singlet-triplet splitting (ΔST = ET–ES) of 9,10-anthracyne. At the DSRG-MRPT3 level of theory, our best estimate of the adiabatic ΔST is 3.9 kcal mol–1, a value that is within 0.1 kcal mol–1 from multireference coupled cluster results.« less

  6. Driven similarity renormalization group: Third-order multireference perturbation theory.

    PubMed

    Li, Chenyang; Evangelista, Francesco A

    2017-03-28

    A third-order multireference perturbation theory based on the driven similarity renormalization group (DSRG-MRPT3) approach is presented. The DSRG-MRPT3 method has several appealing features: (a) it is intruder free, (b) it is size consistent, (c) it leads to a non-iterative algorithm with O(N(6)) scaling, and (d) it includes reference relaxation effects. The DSRG-MRPT3 scheme is benchmarked on the potential energy curves of F2, H2O2, C2H6, and N2 along the F-F, O-O, C-C, and N-N bond dissociation coordinates, respectively. The nonparallelism errors of DSRG-MRPT3 are consistent with those of complete active space third-order perturbation theory and multireference configuration interaction with singles and doubles and show significant improvements over those obtained from DSRG second-order multireference perturbation theory. Our efficient implementation of the DSRG-MRPT3 based on factorized electron repulsion integrals enables studies of medium-sized open-shell organic compounds. This point is demonstrated with computations of the singlet-triplet splitting (ΔST=ET-ES) of 9,10-anthracyne. At the DSRG-MRPT3 level of theory, our best estimate of the adiabatic ΔST is 3.9 kcal mol(-1), a value that is within 0.1 kcal mol(-1) from multireference coupled cluster results.

  7. Conceptual Similarity Promotes Generalization of Higher Order Fear Learning

    ERIC Educational Resources Information Center

    Dunsmoor, Joseph E.; White, Allison J.; LaBar, Kevin S.

    2011-01-01

    We tested the hypothesis that conceptual similarity promotes generalization of conditioned fear. Using a sensory preconditioning procedure, three groups of subjects learned an association between two cues that were conceptually similar, unrelated, or mismatched. Next, one of the cues was paired with a shock. The other cue was then reintroduced to…

  8. Conceptual Similarity Promotes Generalization of Higher Order Fear Learning

    ERIC Educational Resources Information Center

    Dunsmoor, Joseph E.; White, Allison J.; LaBar, Kevin S.

    2011-01-01

    We tested the hypothesis that conceptual similarity promotes generalization of conditioned fear. Using a sensory preconditioning procedure, three groups of subjects learned an association between two cues that were conceptually similar, unrelated, or mismatched. Next, one of the cues was paired with a shock. The other cue was then reintroduced to…

  9. Similarity of satellite DNA properties in the order Rodentia

    PubMed Central

    Mazrimas, J. A.; Hatch, F.T.

    1977-01-01

    We have characterized satellite DNAs from 9 species of kangaroo rat (Dipodomys) and have shown that the HS-α and HS-β satellites, where present, are nearly identical in all species as to melting transition midpoint (Tm), and density in neutral CsCl, alkaline CsCl, and Cs2SO4-Ag+ gradients. However, the MS satellites exist in two internally similar classes. The satellite DNAs from three other rodents were characterized (densities listed are in neutral CsCl). The pocket gopher, Thomomysbottae, contains Th-α (1.713 g/ml) and Th-β (1.703 g/ml). The guinea pig (Caviaporcellus) contains Ca-α, Ca-β and Ca-γ at densities of 1.706 g/ml, 1.704 g/ml and 1.704 g/ml, respectively. The antelope ground squirrel (Ammospermophilusharrisi) contains Am-α, 1.708 g/ml, Am-β, 1.717 g/ml, and Am-γ, 1.707 g/ml. The physical and chemical properties of the alpha-satellites from the above four rodents representing four different families in two suborders of Rodentia were compared. They show nearly identical Tm, nucleoside composition of single strands, and single strand densities in alkaline CsCl. Similar comparisons on the second or third satellite DNAs from these rodents also indicate a close relationship to each other. Thus the high degree of similarity of satellite sequences found in such a diverse group of rodents suggests a cellular function that is subject to natural selection, and implies that these sequences have been conserved over a considerable span of evolutionary time since the divergence of these rodents about 50 million years ago. PMID:561953

  10. The foldon universe: a survey of structural similarity and self-recognition of independently folding units.

    PubMed

    Panchenko, A R; Luthey-Schulten, Z; Cole, R; Wolynes, P G

    1997-09-12

    We have identified independently folding units, so called "foldons", from non-homologous proteins representing different folds. We applied simple statistical arguments in order to estimate the size of the foldon universe required to construct all foldable proteins. Various alignment procedures yield about 2600 foldons in the natural protein universe but this estimate is shown to be rather sensitive to the chosen cut-off value for structural similarity. We showed that foldon matching-modelling can reproduce the major part of the main chain of several proteins with a structural similarity measure Q-score of about 0.4 and an r.m.s. error of about 5 A, although the accuracy of structure prediction has been limited so far by the small size of foldon data set. The prediction score may be increased if one uses the set of protein fragments with optimized sequence-structure relationships, in other works, minimally frustrated segments. To quantify the degree of frustration of the structures of foldons from our database, we searched for those foldons which recognize their own sequence and structure upon threading. As a result we found that about half of the foldons from our data set recognize themselves as the best choice upon threading and therefore are individually minimally frustrated. We showed that there is a close connection between the Q-score of self recognition and the relative foldability (Theta) of the folding units. Foldons having high Q-score and Theta values are expected to be formed in the early phase of the folding process and be observed as stable intermediates under appropriate experimental conditions. Copyright 1997 Academic Press Limited.

  11. Strong Similarity Measures for Ordered Sets of Documents in Information Retrieval.

    ERIC Educational Resources Information Center

    Egghe, L.; Michel, Christine

    2002-01-01

    Presents a general method to construct ordered similarity measures in information retrieval based on classical similarity measures for ordinary sets. Describes a test of some of these measures in an information retrieval system that extracted ranked document sets and discuses the practical usability of the ordered similarity measures. (Author/LRW)

  12. Similarity

    NASA Technical Reports Server (NTRS)

    Apostol, Tom M. (Editor)

    1990-01-01

    In this 'Project Mathematics! series, sponsored by the California Institute for Technology (CalTech), the mathematical concept of similarity is presented. he history of and real life applications are discussed using actual film footage and computer animation. Terms used and various concepts of size, shape, ratio, area, and volume are demonstrated. The similarity of polygons, solids, congruent triangles, internal ratios, perimeters, and line segments using the previous mentioned concepts are shown.

  13. Similarity

    NASA Technical Reports Server (NTRS)

    Apostol, Tom M. (Editor)

    1990-01-01

    In this 'Project Mathematics! series, sponsored by the California Institute for Technology (CalTech), the mathematical concept of similarity is presented. he history of and real life applications are discussed using actual film footage and computer animation. Terms used and various concepts of size, shape, ratio, area, and volume are demonstrated. The similarity of polygons, solids, congruent triangles, internal ratios, perimeters, and line segments using the previous mentioned concepts are shown.

  14. Similar phenomena, different mechanisms: semantic and phonological false memories are produced by independent mechanisms.

    PubMed

    Ballou, McKenzie R; Sommers, Mitchell S

    2008-12-01

    The Deese/Roediger-McDermott paradigm can produce high levels of false remembering for lists of both semantic and phonological associates. The present study investigated whether similar mechanisms mediate false memories with these two types of lists. Experiment 1 measured the relationship between levels of false memory obtained with lists of semantic and phonological associates. The results indicated little correlation between false memories generated with the two types of associates. Experiment 2 used a between-subjects design to determine whether the absence of a significant correlation in Experiment 1 was a consequence of the relatively low levels of false memory observed in that experiment. The results indicated similar proportions of false memories in Experiments 1 and 2, suggesting that the within-subjects design in Experiment 1 did not reduce the overall levels of false recall or recognition. The results are discussed in terms of their implications for the independence of the mechanisms mediating different types of false memories.

  15. Cation Ordering in [(Tl,M)O] Layers of ``1201''-Based Cuprates: Similarity to Ordering in fcc-Based Alloys

    NASA Astrophysics Data System (ADS)

    Van Tendeloo, G.; De Meulenaere, P.; Letouzé, F.; Martin, C.; Hervieu, M.; Raveau, B.

    1997-08-01

    "1201" Tl-based substituted cuprates of the type (Tl1-xMx)Sr2CuO5have been synthesized forM=Nb, Ta, or W. These materials do not superconduct due to a statistical distribution of some of theMfor Cu. The remarkable feature of these materials is the ordering observed between Tl andMin the (Tl1-xMx-ε)O plane. The type of ordering depends on the composition and shows remarkable similarities with the ordering in Ni-Mo or other so-called 1 1/2 0 type fcc-based alloys or with the ordering in rocksalt oxides TiOx. The short-range order, forM=W, can be readily interpreted in terms of a mixing of nano-clusters with two different compositions. These observations of two-dimensional ordering confirm recent ideas about ordering in three-dimensional fcc-based alloys.

  16. 3 CFR 13579 - Executive Order 13579 of July 11, 2011. Regulation and Independent Regulatory Agencies

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 3 The President 1 2012-01-01 2012-01-01 false Executive Order 13579 of July 11, 2011. Regulation and Independent Regulatory Agencies 13579 Order 13579 Presidential Documents Executive Orders Executive Order 13579 of July 11, 2011 EO 13579 Regulation and Independent Regulatory Agencies By...

  17. Spectroscopic signatures of an ordered array of independent Ag heptamers.

    PubMed

    Moras, P; Sheverdyaeva, P M; Pacilé, D; Carbone, C

    2015-08-05

    A periodic network of Ag heptamers forms on the carburized W(1 1 0)-R(15 × 12) surface, upon deposition of sub-monolayer amounts of Ag. We investigate the electronic structure and dimensionality of this system by angle-resolved photoemission spectroscopy. The observation of very well-defined Ag 4d-levels confirms the highly ordered growth of size-selected Ag nano-particles on the W(1 1 0)-R(15 × 12) template. The absence of energy dispersion of these states indicates negligible coupling among the Ag heptamers, and points out the local character of the heptamer-substrate interaction. The system can be described as an array of Ag heptamers with fully confined Ag 4d-levels.

  18. Similarity, independence, or interaction for binary mixture effects of nerve toxicants for the nematode Caenorhabditis elegans.

    PubMed

    Svendsen, Claus; Siang, Pia; Lister, Lindsay J; Rice, Annabel; Spurgeon, David J

    2010-05-01

    Intensive agriculture can require the simultaneous use of more than one pesticide, resulting in the presence of mixtures in soils and waters. To assess mixture effects, concentration addition (CA) for similar acting chemicals and independent action (IA) for dissimilar acting chemicals are the most frequently used models. While the mechanistic basis for the selection of CA and IA for a given mixture appears appealing (similar vs dissimilar action), it has not yet been established how similar chemicals need to be in their effect before CA should be viewed as the most appropriate model. Here this is investigated in studies of the toxicity of binary mixtures of five different pesticides from three classes that have the same putative mode of action (neuroexcitation) but different molecular mechanisms in binary mixture tests with the nematode Caenorhabditis elegans. Effects of exposure on nematode survival were limited at the concentrations tested. Data analysis, therefore, focused on reproductive toxicity. Both CA and IA were found to be valid models for prediction of the toxicity of the 10 mixtures, although for seven CA provided a mathematically better fit. Both models could describe the toxicity for four mixtures; however, evidence for interaction was found in the remaining six cases. Where interactions occurred, these could be explained by information on the potential mechanisms of compound toxicokinetics-particularly when mixtures comprised a metabolically activated and a metabolically deactivated chemical and/or cases where the relative potencies of the two tested chemicals differed greatly. It is concluded, therefore, that detailed analysis of toxicokinetics and toxicodynamics can aid further understanding of interactions in mixtures. Copyright (c) 2010 SETAC.

  19. Construction of Weak and Strong Similarity Measures for Ordered Sets of Documents Using Fuzzy Set Techniques.

    ERIC Educational Resources Information Center

    Egghe, L.; Michel, C.

    2003-01-01

    Ordered sets (OS) of documents are encountered more and more in information distribution systems, such as information retrieval systems. Classical similarity measures for ordinary sets of documents need to be extended to these ordered sets. This is done in this article using fuzzy set techniques. The practical usability of the OS-measures is…

  20. Braided submarine channels produced with experiments suggest scale independent controls on planform morphology similar to rivers

    NASA Astrophysics Data System (ADS)

    Foreman, B.; Lai, S. Y. J.; Komatsu, Y.; Paola, C.

    2015-12-01

    There are two dominant planform morphologies in channelized aggradational sedimentary systems; meandering and braided. Within marine settings meandering channels formed from turbidity and density currents are the most abundant. Braided channels are rare, and it is unclear if the few documented cases are generated by spontaneous bar deposition or are an artifact of erosive events or seafloor bathymetry. This is in contrast to fluvial systems wherein both meandering and braided planforms are common, and led us to the question if submarine channels require different conditions from river systems to obtain braided planform morphologies. We ran two experimental series wherein we provided density currents with an initial channel geometry known to produce braiding in natural and experimental river systems. Fluvial braiding occurs across a wide range of scales, and we predicted the same would hold true for subaqueous systems. The two experiments had initial width to depth ratios of 1000:1 and 350:1 and similar sediment to saline water discharge ratios of 0.02 and 0.03, and a saline current with a density contrast similar to natural currents. The experiments freely evolved a network of individual channels separated by depositional bars. Moreover, existing stability model theory for fluvial systems successfully explains both braided and meandering submarine channels from a compilation of lab and field examples. This suggests the aspect ratio of the flow determines the planform morphology, and that it is a scale independent phenomenon. The rarity of braided submarine channels in nature is more likely explained by factors that inhibit channel widening in submarine systems as compared to fluvial systems. We suggest the cause is a combination of the relatively thicker flow depths of turbidity currents that require commensurately wider flows, and a variety of feedbacks that tend to yield higher overbank sedimentation rates in submarine channels compared to fluvial systems.

  1. Zeroing In on Mindfulness Facets: Similarities, Validity, and Dimensionality across Three Independent Measures

    PubMed Central

    Siegling, Alex B.; Petrides, K. V.

    2016-01-01

    The field of mindfulness has seen a proliferation of psychometric measures, characterised by differences in operationalisation and conceptualisation. To illuminate the scope of, and offer insights into, the diversity apparent in the burgeoning literature, two distinct samples were used to examine the similarities, validity, and dimensionality of mindfulness facets and subscales across three independent measures: the Five Facet Mindfulness Questionnaire (FFMQ), Philadelphia Mindfulness Scale (PHLMS), and Toronto Mindfulness Scale (TMS). Results revealed problematic associations of FFMQ Observe with the other FFMQ facets and supported a four-factor structure (omitting this facet), while disputing the originally envisaged five-factor model; thus, solidifying a pattern in the literature. Results also confirmed the bidimensional nature of the PHLMS and TMS subscales, respectively. A joint Confirmatory Factor Analysis showed that PHLMS Acceptance could be assimilated within the FFMQ’s four-factor model (as a distinct factor). The study offers a way of understanding interrelationships between the available mindfulness scales, so as to help practitioners and researchers make a more informed choice when conceptualising and operationalising mindfulness. PMID:27055017

  2. Zeroing In on Mindfulness Facets: Similarities, Validity, and Dimensionality across Three Independent Measures.

    PubMed

    Siegling, Alex B; Petrides, K V

    2016-01-01

    The field of mindfulness has seen a proliferation of psychometric measures, characterised by differences in operationalisation and conceptualisation. To illuminate the scope of, and offer insights into, the diversity apparent in the burgeoning literature, two distinct samples were used to examine the similarities, validity, and dimensionality of mindfulness facets and subscales across three independent measures: the Five Facet Mindfulness Questionnaire (FFMQ), Philadelphia Mindfulness Scale (PHLMS), and Toronto Mindfulness Scale (TMS). Results revealed problematic associations of FFMQ Observe with the other FFMQ facets and supported a four-factor structure (omitting this facet), while disputing the originally envisaged five-factor model; thus, solidifying a pattern in the literature. Results also confirmed the bidimensional nature of the PHLMS and TMS subscales, respectively. A joint Confirmatory Factor Analysis showed that PHLMS Acceptance could be assimilated within the FFMQ's four-factor model (as a distinct factor). The study offers a way of understanding interrelationships between the available mindfulness scales, so as to help practitioners and researchers make a more informed choice when conceptualising and operationalising mindfulness.

  3. Mathematical evaluation of similarity factor using various weighing approaches on aceclofenac marketed formulations by model-independent method.

    PubMed

    Soni, T G; Desai, J U; Nagda, C D; Gandhi, T R; Chotai, N P

    2008-01-01

    The US Food and Drug Administration's (FDA's) guidance for industry on dissolution testing of immediate-release solid oral dosage forms describes that drug dissolution may be the rate limiting step for drug absorption in the case of low solubility/high permeability drugs (BCS class II drugs). US FDA Guidance describes the model-independent mathematical approach proposed by Moore and Flanner for calculating a similarity factor (f2) of dissolution across a suitable time interval. In the present study, the similarity factor was calculated on dissolution data of two marketed aceclofenac tablets (a BCS class II drug) using various weighing approaches proposed by Gohel et al. The proposed approaches were compared with a conventional approach (W = 1). On the basis of consideration of variability, preference is given in the order of approach 3 > approach 2 > approach 1 as approach 3 considers batch-to-batch as well as within-samples variability and shows best similarity profile. Approach 2 considers batch-to batch variability with higher specificity than approach 1.

  4. Assessing the differences and similarities between hospital chains and independents regarding revenues, profits, and community contributions.

    PubMed

    McDermott, Dennis R

    2009-01-01

    Hospital systems or chains continue to grow their market share relative to independent hospitals. This trend generates concerns among health care industry observers as historical performance suggests chains charge more for health care services than the independents while providing reduced contributions to their community. This study empirically assesses key performance measures of 67 acute-care hospitals in Virginia by testing if there are differences between chains and independents regarding total patient revenues, revenues per admission, profitability and community support, including charity care, bad debt, taxes paid and Medicaid participation. Implications to industry policy-makers as well as to hospital executives and marketing managers are then presented.

  5. A negative semantic similarity effect on short-term order memory: evidence from recency judgements.

    PubMed

    Tse, Chi-Shing

    2010-08-01

    Speeded recency judgements were used to examine whether judgements concerning the relative temporal order in which two items were presented on a short eight-item, study list would be facilitated or hindered when the two items were from the same semantic category (related, R, items), relative to when they were from different categories (unrelated, U, items). Semantic similarity led to slower and less accurate recency judgements. To evaluate the extent that item memory contributes to recency judgement performance, I used speeded pair recognition and speeded two-alternative forced-choice (2AFC) recognition trials, in which the stimuli and designs were the same as in the recency judgement test. The type of test trial was manipulated between subjects (recency judgement vs pair recognition) or within participants (recency judgement and 2AFC recognition). Regardless of the between- or within-participants manipulation of recognition vs order memory tests, the pattern of recognition performance was very different from the pattern of recency judgement performance, indicating that semantic similarity had a negative effect on order memory per se. The explanation of the current findings offered by position-based order memory theories is discussed. © 2010 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business

  6. Technique of Order Preference by Similarity for Multiple Attribute Decision Making Based on Grey Members

    NASA Astrophysics Data System (ADS)

    Xu, Jiuping; Sasaki, Masato

    The aim of this paper is to extend the technique of order preference by similarity to ideal and anti-ideal alternative to the Grey system. In general, multi-attribute problems in real-life situation have uncertain and imprecise data while Grey system theory is to deal with a linguistic decision process to solve the decision-making problems under uncertainty environment. In this paper, the rating of each alternative and the weight of each criterion are described by linguistic terms that can be expressed in Grey numbers. Further, vertex method is proposed to calculate the distance between Grey numbers. According to the concept of the technique of order preference by similarity to ideal and anti-ideal alternative, a closeness coefficient is defined to determine the ranking order of all alternatives by calculating the distances to both the Grey ideal solution (GIS) and Grey anti-ideal solution (GAIS) simultaneously. Finally, an example is shown to highlight the procedure of the proposed method.

  7. Similar negative impacts of temperature on global wheat yield estimated by three independent methods

    USDA-ARS?s Scientific Manuscript database

    The potential impact of global temperature change on global wheat production has recently been assessed with different methods, scaling and aggregation approaches. Here we show that grid-based simulations, point-based simulations, and statistical regressions produce similar estimates of temperature ...

  8. Query-by-Sketch Image Retrieval Using Similarity in Stroke Order

    NASA Astrophysics Data System (ADS)

    Hisamori, Takashi; Arikawa, Toru; Ohashi, Gosuke

    In previous studies, the retrieval accuracy of large image databases has been improved as a result of reducing the semantic gap by combining the input sketch with relevance feedback. A further improvement of retrieval accuracy is expected by combining each stroke, and its order, of the input sketch with the relevance feedback. However, this leaves as a problem the fact that the effect of the relevance feedback substantially depends on the stroke order in the input sketch. Although it is theoretically possible to consider all the possible stroke orders, that would cause a realistic problem of creating an enormous amount of data. Consequently, the technique introduced in this paper intends to improve retrieval efficiency by effectively using the relevance feedback by means of conducting data mining of the sketch considering the similarity in the order of strokes. To ascertain the effectiveness of this technique, a retrieval experiment was conducted using 20, 000 images of a collection, the Corel Photo Gallery, and the experiment was able to confirm an improvement in the retrieval efficiency.

  9. IP-MSA: Independent order of progressive multiple sequence alignments using different substitution matrices

    NASA Astrophysics Data System (ADS)

    Boraik, Aziz Nasser; Abdullah, Rosni; Venkat, Ibrahim

    2014-12-01

    Multiple sequence alignment (MSA) is an essential process for many biological sequence analyses. There are many algorithms developed to solve MSA, but an efficient computation method with very high accuracy is still a challenge. Progressive alignment is the most widely used approach to compute the final MSA. In this paper, we present a simple and effective progressive approach. Based on the independent order of sequences progressive alignment which proposed in QOMA, this method has been modified to align the whole sequences to maximize the score of MSA. Moreover, in order to further improve the accuracy of the method, we estimate the similarity of any pair of input sequences by using their percent identity, and based on this measure, we choose different substitution matrices during the progressive alignment. In addition, we have included horizontal information to alignment by adjusting the weights of amino acid residues based on their neighboring residues. The experimental results have been tested on popular benchmark of global protein sequences BAliBASE 3.0 and local protein sequences IRMBASE 2.0. The results of the proposed approach outperform the original method in QOMA in terms of sum-of-pair score and column score by up to 14% and 7% respectively.

  10. Efficacy of independence sampling in replica exchange simulations of ordered and disordered proteins.

    PubMed

    Lee, Kuo Hao; Chen, Jianhan

    2017-08-25

    Recasting temperature replica exchange (T-RE) as a special case of Gibbs sampling has led to a simple and efficient scheme for enhanced mixing (Chodera and Shirts, J. Chem. Phys., 2011, 135, 194110). To critically examine if T-RE with independence sampling (T-REis) improves conformational sampling, we performed T-RE and T-REis simulations of ordered and disordered proteins using coarse-grained and atomistic models. The results demonstrate that T-REis effectively increase the replica mobility in temperatures space with minimal computational overhead, especially for folded proteins. However, enhanced mixing does not translate well into improved conformational sampling. The convergences of thermodynamic properties interested are similar, with slight improvements for T-REis of ordered systems. The study re-affirms the efficiency of T-RE does not appear to be limited by temperature diffusion, but by the inherent rates of spontaneous large-scale conformational re-arrangements. Due to its simplicity and efficacy of enhanced mixing, T-REis is expected to be more effective when incorporated with various Hamiltonian-RE protocols. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  11. Polyethylene and titanium particles induce osteolysis by similar, lymphocyte-independent, mechanisms.

    PubMed

    Taki, Naoya; Tatro, Joscelyn M; Nalepka, Jennifer L; Togawa, Daisuke; Goldberg, Victor M; Rimnac, Clare M; Greenfield, Edward M

    2005-03-01

    Periprosthetic osteolysis is a major clinical problem that limits the long-term survival of total joint arthroplasties. Osteolysis is induced by implant-derived wear particles, primarily from the polyethylene bearing surfaces. This study examined two hypotheses. First, that similar mechanisms are responsible for osteolysis induced by polyethylene and titanium particles. Second, that lymphocytes do not play a major role in particle-induced osteolysis. To test these hypotheses, we used the murine calvarial model that we have previously used to examine titanium-induced osteolysis. Polyethylene particles rapidly induced osteolysis in the murine calvaria 5-7 days after implantation. The polyethylene-induced osteolysis was associated with large numbers of osteoclasts as well as the formation of a thick periosteal fibrous tissue layer with numerous macrophages containing phagocytosed polyethylene particles. Polyethylene-induced osteolysis was rapidly repaired and was undetectable by day 21 after implantation. Lymphocytes were noted in the fibrous layer of wild-type mice. However, the amount of osteolysis and cytokine production induced by polyethylene particles was not substantially affected by the lack of lymphocytes in Pfp/Rag2 double knock out mice. All of these findings are similar to our observations of osteolysis induced by titanium particles. These results provide strong support for both of our hypotheses: that similar mechanisms are responsible for osteolysis induced by polyethylene and titanium particles and that lymphocytes do not play a major role in particle-induced osteolysis.

  12. Hg concentrations from Late Triassic and Early Jurassic sedimentary rocks: first order similarities and second order depositional and diagenetic controls

    NASA Astrophysics Data System (ADS)

    Yager, J. A.; West, A. J.; Bergquist, B. A.; Thibodeau, A. M.; Corsetti, F. A.; Berelson, W.; Bottjer, D. J.; Rosas, S.

    2016-12-01

    Mercury concentrations in sediments have recently gained prominence as a potential tool for identifying large igneous province (LIP) volcanism in sedimentary records. LIP volcanism coincides with several mass extinctions during the Phanerozoic, but it is often difficult to directly tie LIP activity with the record of extinction in marine successions. Here, we build on mercury concentration data reported by Thibodeau et al. (Nature Communications, 7:11147, 2016) from the Late Triassic and Early Jurassic of New York Canyon, Nevada, USA. Increases in Hg concentrations in that record were attributed to Central Atlantic Magmatic Province (CAMP) activity in association with the end-Triassic mass extinction. We expand the measured section from New York Canyon and report new mercury concentrations from Levanto, Peru, where dated ash beds provide a discrete chronology, as well as St. Audrie's Bay, UK, a well-studied succession. We correlate these records using carbon isotopes and ammonites and find similarities in the onset of elevated Hg concentrations and Hg/TOC in association with changes in C isotopes. We also find second order patterns that differ between sections and may have depositional and diagenetic controls. We will discuss these changes within a sedimentological framework to further understand the controls on Hg concentrations in sedimentary records and their implications for past volcanism.

  13. Similar Estimates of Temperature Impacts on Global Wheat Yield by Three Independent Methods

    NASA Technical Reports Server (NTRS)

    Liu, Bing; Asseng, Senthold; Muller, Christoph; Ewart, Frank; Elliott, Joshua; Lobell, David B.; Martre, Pierre; Ruane, Alex C.; Wallach, Daniel; Jones, James W.; Rosenzweig, Cynthia; Deryng, Delphine

    2016-01-01

    The potential impact of global temperature change on global crop yield has recently been assessed with different methods. Here we show that grid-based and point-based simulations and statistical regressions (from historic records), without deliberate adaptation or CO2 fertilization effects, produce similar estimates of temperature impact on wheat yields at global and national scales. With a 1 C global temperature increase, global wheat yield is projected to decline between 4.1% and 6.4%. Projected relative temperature impacts from different methods were similar for major wheat-producing countries China, India, USA and France, but less so for Russia. Point-based and grid-based simulations, and to some extent the statistical regressions, were consistent in projecting that warmer regions are likely to suffer more yield loss with increasing temperature than cooler regions. By forming a multi-method ensemble, it was possible to quantify 'method uncertainty' in addition to model uncertainty. This significantly improves confidence in estimates of climate impacts on global food security.

  14. Similar estimates of temperature impacts on global wheat yield by three independent methods

    NASA Astrophysics Data System (ADS)

    Liu, Bing; Asseng, Senthold; Müller, Christoph; Ewert, Frank; Elliott, Joshua; Lobell, David B.; Martre, Pierre; Ruane, Alex C.; Wallach, Daniel; Jones, James W.; Rosenzweig, Cynthia; Aggarwal, Pramod K.; Alderman, Phillip D.; Anothai, Jakarat; Basso, Bruno; Biernath, Christian; Cammarano, Davide; Challinor, Andy; Deryng, Delphine; Sanctis, Giacomo De; Doltra, Jordi; Fereres, Elias; Folberth, Christian; Garcia-Vila, Margarita; Gayler, Sebastian; Hoogenboom, Gerrit; Hunt, Leslie A.; Izaurralde, Roberto C.; Jabloun, Mohamed; Jones, Curtis D.; Kersebaum, Kurt C.; Kimball, Bruce A.; Koehler, Ann-Kristin; Kumar, Soora Naresh; Nendel, Claas; O'Leary, Garry J.; Olesen, Jørgen E.; Ottman, Michael J.; Palosuo, Taru; Prasad, P. V. Vara; Priesack, Eckart; Pugh, Thomas A. M.; Reynolds, Matthew; Rezaei, Ehsan E.; Rötter, Reimund P.; Schmid, Erwin; Semenov, Mikhail A.; Shcherbak, Iurii; Stehfest, Elke; Stöckle, Claudio O.; Stratonovitch, Pierre; Streck, Thilo; Supit, Iwan; Tao, Fulu; Thorburn, Peter; Waha, Katharina; Wall, Gerard W.; Wang, Enli; White, Jeffrey W.; Wolf, Joost; Zhao, Zhigan; Zhu, Yan

    2016-12-01

    The potential impact of global temperature change on global crop yield has recently been assessed with different methods. Here we show that grid-based and point-based simulations and statistical regressions (from historic records), without deliberate adaptation or CO2 fertilization effects, produce similar estimates of temperature impact on wheat yields at global and national scales. With a 1 °C global temperature increase, global wheat yield is projected to decline between 4.1% and 6.4%. Projected relative temperature impacts from different methods were similar for major wheat-producing countries China, India, USA and France, but less so for Russia. Point-based and grid-based simulations, and to some extent the statistical regressions, were consistent in projecting that warmer regions are likely to suffer more yield loss with increasing temperature than cooler regions. By forming a multi-method ensemble, it was possible to quantify `method uncertainty’ in addition to model uncertainty. This significantly improves confidence in estimates of climate impacts on global food security.

  15. Similar Estimates of Temperature Impacts on Global Wheat Yield by Three Independent Methods

    NASA Technical Reports Server (NTRS)

    Liu, Bing; Asseng, Senthold; Muller, Christoph; Ewart, Frank; Elliott, Joshua; Lobell, David B.; Martre, Pierre; Ruane, Alex C.; Wallach, Daniel; Jones, James W.; hide

    2016-01-01

    The potential impact of global temperature change on global crop yield has recently been assessed with different methods. Here we show that grid-based and point-based simulations and statistical regressions (from historic records), without deliberate adaptation or CO2 fertilization effects, produce similar estimates of temperature impact on wheat yields at global and national scales. With a 1 C global temperature increase, global wheat yield is projected to decline between 4.1% and 6.4%. Projected relative temperature impacts from different methods were similar for major wheat-producing countries China, India, USA and France, but less so for Russia. Point-based and grid-based simulations, and to some extent the statistical regressions, were consistent in projecting that warmer regions are likely to suffer more yield loss with increasing temperature than cooler regions. By forming a multi-method ensemble, it was possible to quantify 'method uncertainty' in addition to model uncertainty. This significantly improves confidence in estimates of climate impacts on global food security.

  16. The development of the Poincare-similar elements with true anomaly as the independent variable

    NASA Technical Reports Server (NTRS)

    Mueller, A.

    1976-01-01

    In reference 1, the Hamiltonian of the unperturbed two-body problem in extended phase space is established. Depending on the type of time transformation, eight canonical elements were developed with the true anomaly or the eccentric anomaly as the independent variable. These two new sets, DS(phi) and DS(u), however contain singularities for small eccentricities and inclinations. In reference 2, these singularities are removed by a transformation from DS(u) to eight canonical PS(u) elements. In reference 3, the DS(phi) variables are transformed to the PS(phi) elements to remove the singularities. However, no direct relation was established between the eight canonical PS(phi) elements and the Cartesian coordinates. It is the purpose of this report to establish those relations and to develop the perturbed equations of motion in the PS(phi) space. This report also demonstrates the accuracy of this new set when it is applied to numerical orbit prediction problems.

  17. Modality independence of order coding in working memory: Evidence from cross-modal order interference at recall.

    PubMed

    Vandierendonck, André

    2016-01-01

    Working memory researchers do not agree on whether order in serial recall is encoded by dedicated modality-specific systems or by a more general modality-independent system. Although previous research supports the existence of autonomous modality-specific systems, it has been shown that serial recognition memory is prone to cross-modal order interference by concurrent tasks. The present study used a serial recall task, which was performed in a single-task condition and in a dual-task condition with an embedded memory task in the retention interval. The modality of the serial task was either verbal or visuospatial, and the embedded tasks were in the other modality and required either serial or item recall. Care was taken to avoid modality overlaps during presentation and recall. In Experiment 1, visuospatial but not verbal serial recall was more impaired when the embedded task was an order than when it was an item task. Using a more difficult verbal serial recall task, verbal serial recall was also more impaired by another order recall task in Experiment 2. These findings are consistent with the hypothesis of modality-independent order coding. The implications for views on short-term recall and the multicomponent view of working memory are discussed.

  18. LASSO—ligand activity by surface similarity order: a new tool for ligand based virtual screening

    NASA Astrophysics Data System (ADS)

    Reid, Darryl; Sadjad, Bashir S.; Zsoldos, Zsolt; Simon, Aniko

    2008-06-01

    Virtual Ligand Screening (VLS) has become an integral part of the drug discovery process for many pharmaceutical companies. Ligand similarity searches provide a very powerful method of screening large databases of ligands to identify possible hits. If these hits belong to new chemotypes the method is deemed even more successful. eHiTS LASSO uses a new interacting surface point types (ISPT) molecular descriptor that is generated from the 3D structure of the ligand, but unlike most 3D descriptors it is conformation independent. Combined with a neural network machine learning technique, LASSO screens molecular databases at an ultra fast speed of 1 million structures in under 1 min on a standard PC. The results obtained from eHiTS LASSO trained on relatively small training sets of just 2, 4 or 8 actives are presented using the diverse directory of useful decoys (DUD) dataset. It is shown that over a wide range of receptor families, eHiTS LASSO is consistently able to enrich screened databases and provides scaffold hopping ability.

  19. Similar Representations of Sequence Knowledge in Young and Older Adults: A Study of Effector Independent Transfer

    PubMed Central

    Barnhoorn, Jonathan S.; Döhring, Falko R.; Van Asseldonk, Edwin H. F.; Verwey, Willem B.

    2016-01-01

    Older adults show reduced motor performance and changes in motor skill development. To better understand these changes, we studied differences in sequence knowledge representations between young and older adults using a transfer task. Transfer, or the ability to apply motor skills flexibly, is highly relevant in day-to-day motor activity and facilitates generalization of learning to new contexts. By using movement types that are completely unrelated in terms of muscle activation and response location, we focused on transfer facilitated by the early, visuospatial system. We tested 32 right-handed older adults (65–75) and 32 young adults (18–30). During practice of a discrete sequence production task, participants learned two six-element sequences using either unimanual key-presses (KPs) or by moving a lever with lower arm flexion-extension (FE) movements. Each sequence was performed 144 times. They then performed a test phase consisting of familiar and random sequences performed with the type of movements not used during practice. Both age groups displayed transfer from FE to KP movements as indicated by faster performance on the familiar sequences in the test phase. Only young adults transferred their sequence knowledge from KP to FE movements. In both directions, the young showed higher transfer than older adults. These results suggest that the older participants, like the young, represented their sequences in an abstract visuospatial manner. Transfer was asymmetric in both age groups: there was more transfer from FE to KP movements than vice versa. This similar asymmetry is a further indication that the types of representations that older adults develop are comparable to those that young adults develop. We furthermore found that older adults improved less during FE practice, gained less explicit knowledge, displayed a smaller visuospatial working memory capacity and had lower processing speed than young adults. Despite the many differences between young and

  20. Second-order temporal interference of two independent light beams at an asymmetrical beam splitter

    NASA Astrophysics Data System (ADS)

    Liu, Jianbin; Wang, Jingjing; Xu, Zhuo

    2017-01-01

    The second-order temporal interference of classical and nonclassical light at an asymmetrical beam splitter is discussed based on two-photon interference in Feynman's path integral theory. The visibility of the second-order interference pattern is determined by the properties of the superposed light beams, the ratio between the intensities of these two light beams, and the reflectivity of the asymmetrical beam splitter. Some requirements about the asymmetrical beam splitter have to be satisfied in order to ensure that the visibility of the second-order interference pattern of nonclassical light beams exceeds classical limit. The visibility of the second-order interference pattern of photons emitted by two independent single-photon sources is independent of the ratio between the intensities. These conclusions are important for the researches and applications in quantum optics and quantum information when asymmetrical beam splitter is employed.

  1. Distinctive Order Based Self-Similarity descriptor for multi-sensor remote sensing image matching

    NASA Astrophysics Data System (ADS)

    Sedaghat, Amin; Ebadi, Hamid

    2015-10-01

    Robust, well-distributed and accurate feature matching in multi-sensor remote sensing image is a difficult task duo to significant geometric and illumination differences. In this paper, a robust and effective image matching approach is presented for multi-sensor remote sensing images. The proposed approach consists of three main steps. In the first step, UR-SIFT (Uniform robust scale invariant feature transform) algorithm is applied for uniform and dense local feature extraction. In the second step, a novel descriptor namely Distinctive Order Based Self Similarity descriptor, DOBSS descriptor, is computed for each extracted feature. Finally, a cross matching process followed by a consistency check in the projective transformation model is performed for feature correspondence and mismatch elimination. The proposed method was successfully applied for matching various multi-sensor satellite images as: ETM+, SPOT 4, SPOT 5, ASTER, IRS, SPOT 6, QuickBird, GeoEye and Worldview sensors, and the results demonstrate its robustness and capability compared to common image matching techniques such as SIFT, PIIFD, GLOH, LIOP and LSS.

  2. Birth Order and Field Dependence-Independence: A Failure to Replicate

    ERIC Educational Resources Information Center

    Finley, Gordon E.; Solla, Joseph

    1975-01-01

    The Children's Embedded Figures Test was individually administered to 116 Caucasian, middle class, second grade children. Results suggest that a child's early experience in a particular birth order position may not be related to the development of field dependence-independence in any unambiguous and simple fashion. (Author/ED)

  3. Birth order and sexual orientation in men: evidence for two independent interactions.

    PubMed

    Bogaert, Anthony F; Liu, Jian

    2006-11-01

    Birth order is correlated with male sexual orientation, but the reason(s) for this relationship is unclear. In the present study, data from a Canadian sample of homosexual and heterosexual men (N=604) were used to present evidence of two independent birth order interactions--one with height and the other with parental age--predicting sexual orientation in men. If these findings prove reliable, it raises the possibility that different aetiological factors underlie the birth order/sexual orientation relationship in men.

  4. Mesh independent convergence of the modified inexact Newton method for a second order nonlinear problem

    SciTech Connect

    Kim, T; Pasciak, J E; Vassilevski, P S

    2004-09-20

    In this paper, we consider an inexact Newton method applied to a second order nonlinear problem with higher order nonlinearities. We provide conditions under which the method has a mesh-independent rate of convergence. To do this, we are required to first, set up the problem on a scale of Hilbert spaces and second, to devise a special iterative technique which converges in a higher than first order Sobolev norm. We show that the linear (Jacobian) system solved in Newton's method can be replaced with one iterative step provided that the initial nonlinear iterate is accurate enough. The closeness criteria can be taken independent of the mesh size. Finally, the results of numerical experiments are given to support the theory.

  5. First Things First: Similar List Length and Output Order Effects for Verbal and Nonverbal Stimuli

    ERIC Educational Resources Information Center

    Cortis, Cathleen; Dent, Kevin; Kennett, Steffan; Ward, Geoff

    2015-01-01

    When participants are presented with a short list of unrelated words and they are instructed that they may recall in any order, they nevertheless show a very strong tendency to recall in forward serial order. Thus, if asked to recall "in any orde"r: "hat, mouse, tea, stairs," participants often respond "hat, mouse, tea,…

  6. First Things First: Similar List Length and Output Order Effects for Verbal and Nonverbal Stimuli

    ERIC Educational Resources Information Center

    Cortis, Cathleen; Dent, Kevin; Kennett, Steffan; Ward, Geoff

    2015-01-01

    When participants are presented with a short list of unrelated words and they are instructed that they may recall in any order, they nevertheless show a very strong tendency to recall in forward serial order. Thus, if asked to recall "in any orde"r: "hat, mouse, tea, stairs," participants often respond "hat, mouse, tea,…

  7. Geomfinder: a multi-feature identifier of similar three-dimensional protein patterns: a ligand-independent approach.

    PubMed

    Núñez-Vivanco, Gabriel; Valdés-Jiménez, Alejandro; Besoaín, Felipe; Reyes-Parada, Miguel

    2016-01-01

    Since the structure of proteins is more conserved than the sequence, the identification of conserved three-dimensional (3D) patterns among a set of proteins, can be important for protein function prediction, protein clustering, drug discovery and the establishment of evolutionary relationships. Thus, several computational applications to identify, describe and compare 3D patterns (or motifs) have been developed. Often, these tools consider a 3D pattern as that described by the residues surrounding co-crystallized/docked ligands available from X-ray crystal structures or homology models. Nevertheless, many of the protein structures stored in public databases do not provide information about the location and characteristics of ligand binding sites and/or other important 3D patterns such as allosteric sites, enzyme-cofactor interaction motifs, etc. This makes necessary the development of new ligand-independent methods to search and compare 3D patterns in all available protein structures. Here we introduce Geomfinder, an intuitive, flexible, alignment-free and ligand-independent web server for detailed estimation of similarities between all pairs of 3D patterns detected in any two given protein structures. We used around 1100 protein structures to form pairs of proteins which were assessed with Geomfinder. In these analyses each protein was considered in only one pair (e.g. in a subset of 100 different proteins, 50 pairs of proteins can be defined). Thus: (a) Geomfinder detected identical pairs of 3D patterns in a series of monoamine oxidase-B structures, which corresponded to the effectively similar ligand binding sites at these proteins; (b) we identified structural similarities among pairs of protein structures which are targets of compounds such as acarbose, benzamidine, adenosine triphosphate and pyridoxal phosphate; these similar 3D patterns are not detected using sequence-based methods; (c) the detailed evaluation of three specific cases showed the versatility

  8. Independence.

    ERIC Educational Resources Information Center

    Stephenson, Margaret E.

    2000-01-01

    Discusses the four planes of development and the periods of creation and crystallization within each plane. Identifies the type of independence that should be achieved by the end of the first two planes of development. Maintains that it is through individual work on the environment that one achieves independence. (KB)

  9. Response Errors Explain the Failure of Independent-Channels Models of Perception of Temporal Order

    PubMed Central

    García-Pérez, Miguel A.; Alcalá-Quintana, Rocío

    2012-01-01

    Independent-channels models of perception of temporal order (also referred to as threshold models or perceptual latency models) have been ruled out because two formal properties of these models (monotonicity and parallelism) are not borne out by data from ternary tasks in which observers must judge whether stimulus A was presented before, after, or simultaneously with stimulus B. These models generally assume that observed responses are authentic indicators of unobservable judgments, but blinks, lapses of attention, or errors in pressing the response keys (maybe, but not only, motivated by time pressure when reaction times are being recorded) may make observers misreport their judgments or simply guess a response. We present an extension of independent-channels models that considers response errors and we show that the model produces psychometric functions that do not satisfy monotonicity and parallelism. The model is illustrated by fitting it to data from a published study in which the ternary task was used. The fitted functions describe very accurately the absence of monotonicity and parallelism shown by the data. These characteristics of empirical data are thus consistent with independent-channels models when response errors are taken into consideration. The implications of these results for the analysis and interpretation of temporal order judgment data are discussed. PMID:22493586

  10. Phonological Similarity Effects in Memory for Serial Order of Cued Speech.

    ERIC Educational Resources Information Center

    Leybaert, Jacqueline; Lechat, Josiane

    2001-01-01

    Two experiments, one with congenitally deaf and one with hearing individuals, investigated memory for serial order via Cued Speech (CS). Deaf individuals, but not hearing individuals experienced with CS, appeared to use the phonology of CS to support their recall. The recency effect was greater for hearing individuals provided with sound than for…

  11. How Similar Are Adult Second Language Learners and Spanish Heritage Speakers? Spanish Clitics and Word Order

    ERIC Educational Resources Information Center

    Montrul, Silvina

    2010-01-01

    Recent studies of heritage speakers, many of whom possess incomplete knowledge of their family language, suggest that these speakers may be linguistically superior to second language (L2) learners only in phonology but not in morphosyntax. This study reexamines this claim by focusing on knowledge of clitic pronouns and word order in 24 L2 learners…

  12. How Similar Are Adult Second Language Learners and Spanish Heritage Speakers? Spanish Clitics and Word Order

    ERIC Educational Resources Information Center

    Montrul, Silvina

    2010-01-01

    Recent studies of heritage speakers, many of whom possess incomplete knowledge of their family language, suggest that these speakers may be linguistically superior to second language (L2) learners only in phonology but not in morphosyntax. This study reexamines this claim by focusing on knowledge of clitic pronouns and word order in 24 L2 learners…

  13. Is Word-Order Similarity Necessary for Cross-Linguistic Structural Priming?

    ERIC Educational Resources Information Center

    Chen, Baoguo; Jia, Yuefang; Wang, Zhu; Dunlap, Susan; Shin, Jeong-Ah

    2013-01-01

    This article presents two experiments employing two structural priming paradigms that investigated whether cross-linguistic syntactic priming occurred in Chinese and English passive sentences that differ in word order (production-to-production priming in Experiment 1 and comprehension-to-production priming in Experiment 2). Results revealed that…

  14. Is Word-Order Similarity Necessary for Cross-Linguistic Structural Priming?

    ERIC Educational Resources Information Center

    Chen, Baoguo; Jia, Yuefang; Wang, Zhu; Dunlap, Susan; Shin, Jeong-Ah

    2013-01-01

    This article presents two experiments employing two structural priming paradigms that investigated whether cross-linguistic syntactic priming occurred in Chinese and English passive sentences that differ in word order (production-to-production priming in Experiment 1 and comprehension-to-production priming in Experiment 2). Results revealed that…

  15. Subject order-independent group ICA (SOI-GICA) for functional MRI data analysis.

    PubMed

    Zhang, Han; Zuo, Xi-Nian; Ma, Shuang-Ye; Zang, Yu-Feng; Milham, Michael P; Zhu, Chao-Zhe

    2010-07-15

    Independent component analysis (ICA) is a data-driven approach to study functional magnetic resonance imaging (fMRI) data. Particularly, for group analysis on multiple subjects, temporally concatenation group ICA (TC-GICA) is intensively used. However, due to the usually limited computational capability, data reduction with principal component analysis (PCA: a standard preprocessing step of ICA decomposition) is difficult to achieve for a large dataset. To overcome this, TC-GICA employs multiple-stage PCA data reduction. Such multiple-stage PCA data reduction, however, leads to variable outputs due to different subject concatenation orders. Consequently, the ICA algorithm uses the variable multiple-stage PCA outputs and generates variable decompositions. In this study, a rigorous theoretical analysis was conducted to prove the existence of such variability. Simulated and real fMRI experiments were used to demonstrate the subject-order-induced variability of TC-GICA results using multiple PCA data reductions. To solve this problem, we propose a new subject order-independent group ICA (SOI-GICA). Both simulated and real fMRI data experiments demonstrated the high robustness and accuracy of the SOI-GICA results compared to those of traditional TC-GICA. Accordingly, we recommend SOI-GICA for group ICA-based fMRI studies, especially those with large data sets. Copyright 2010 Elsevier Inc. All rights reserved.

  16. Bacterial interactomes: Interacting protein partners share similar function and are validated in independent assays more frequently than previously reported.

    DOE PAGES

    Shatsky, Maxim; Allen, Simon; Gold, Barbara; ...

    2016-05-01

    Numerous affinity purification – mass-spectrometry (AP-MS) and yeast two hybrid (Y2H) screens have each defined thousands of pairwise protein-protein interactions (PPIs), most between functionally unrelated proteins. The accuracy of these networks, however, is under debate. Here we present an AP-MS survey of the bacterium Desulfovibrio vulgaris together with a critical reanalysis of nine published bacterial Y2H and AP-MS screens. We have identified 459 high confidence PPIs from D. vulgaris and 391 from Escherichia coli. Compared to the nine published interactomes, our two networks are smaller; are much less highly connected; have significantly lower false discovery rates; and are much moremore » enriched in protein pairs that are encoded in the same operon, have similar functions, and are reproducibly detected in other physical interaction assays. Lastly, our work establishes more stringent benchmarks for the properties of protein interactomes and suggests that bona fide PPIs much more frequently involve protein partners that are annotated with similar functions or that can be validated in independent assays than earlier studies suggested.« less

  17. Bacterial interactomes: Interacting protein partners share similar function and are validated in independent assays more frequently than previously reported.

    SciTech Connect

    Shatsky, Maxim; Allen, Simon; Gold, Barbara; Liu, Nancy L.; Juba, Thomas R.; Elias, Dwayne A; Reveco, Sonia A.; Prathapam, Ramadevi; He, Jennifer; Yang, Wenhong; Szakal, Evelin D.; Liu, Haichuan; Singer, Mary E.; Geller, Jil T.; Lam, Bonita R.; Saini, Avneesh; Trotter, Valentine V.; Hall, Steven C.; Fisher, Susan J.; Brenner, Steven E.; Chhabra, Swapnil; Hazen, Terry C.; Wall, Judy D.; Witkowska, Ewa; Biggin, Mark D.; Chandonia, John-Marc; Butland, Gareth

    2016-05-01

    Numerous affinity purification – mass-spectrometry (AP-MS) and yeast two hybrid (Y2H) screens have each defined thousands of pairwise protein-protein interactions (PPIs), most between functionally unrelated proteins. The accuracy of these networks, however, is under debate. Here we present an AP-MS survey of the bacterium Desulfovibrio vulgaris together with a critical reanalysis of nine published bacterial Y2H and AP-MS screens. We have identified 459 high confidence PPIs from D. vulgaris and 391 from Escherichia coli. Compared to the nine published interactomes, our two networks are smaller; are much less highly connected; have significantly lower false discovery rates; and are much more enriched in protein pairs that are encoded in the same operon, have similar functions, and are reproducibly detected in other physical interaction assays. Lastly, our work establishes more stringent benchmarks for the properties of protein interactomes and suggests that bona fide PPIs much more frequently involve protein partners that are annotated with similar functions or that can be validated in independent assays than earlier studies suggested.

  18. Bacterial interactomes: Interacting protein partners share similar function and are validated in independent assays more frequently than previously reported.

    SciTech Connect

    Shatsky, Maxim; Allen, Simon; Gold, Barbara; Liu, Nancy L.; Juba, Thomas R.; Elias, Dwayne A; Reveco, Sonia A.; Prathapam, Ramadevi; He, Jennifer; Yang, Wenhong; Szakal, Evelin D.; Liu, Haichuan; Singer, Mary E.; Geller, Jil T.; Lam, Bonita R.; Saini, Avneesh; Trotter, Valentine V.; Hall, Steven C.; Fisher, Susan J.; Brenner, Steven E.; Chhabra, Swapnil; Hazen, Terry C.; Wall, Judy D.; Witkowska, Ewa; Biggin, Mark D.; Chandonia, John-Marc; Butland, Gareth

    2016-05-01

    Numerous affinity purification – mass-spectrometry (AP-MS) and yeast two hybrid (Y2H) screens have each defined thousands of pairwise protein-protein interactions (PPIs), most between functionally unrelated proteins. The accuracy of these networks, however, is under debate. Here we present an AP-MS survey of the bacterium Desulfovibrio vulgaris together with a critical reanalysis of nine published bacterial Y2H and AP-MS screens. We have identified 459 high confidence PPIs from D. vulgaris and 391 from Escherichia coli. Compared to the nine published interactomes, our two networks are smaller; are much less highly connected; have significantly lower false discovery rates; and are much more enriched in protein pairs that are encoded in the same operon, have similar functions, and are reproducibly detected in other physical interaction assays. Lastly, our work establishes more stringent benchmarks for the properties of protein interactomes and suggests that bona fide PPIs much more frequently involve protein partners that are annotated with similar functions or that can be validated in independent assays than earlier studies suggested.

  19. Convergence acceleration for time-independent first-order PDE using optimal PNB-approximations

    SciTech Connect

    Holmgren, S.; Branden, H.

    1996-12-31

    We consider solving time-independent (steady-state) flow problems in 2D or 3D governed by hyperbolic or {open_quotes}almost hyperbolic{close_quotes} systems of partial differential equations (PDE). Examples of such PDE are the Euler and the Navier-Stokes equations. The PDE is discretized using a finite difference or finite volume scheme with arbitrary order of accuracy. If the matrix B describes the discretized differential operator and u denotes the approximate solution, the discrete problem is given by a large system of equations.

  20. Plugging Taxonomic Similarity in First-Order Logic Horn Clauses Comparison

    NASA Astrophysics Data System (ADS)

    Ferilli, S.; Biba, M.; di Mauro, N.; Basile, T. M. A.; Esposito, F.

    Horn clause Logic is a powerful representation language exploited in Logic Programming as a computer programming framework and in Inductive Logic Programming as a formalism for expressing examples and learned theories in domains where relations among objects must be expressed to fully capture the relevant information. While the predicates that make up the description language are defined by the knowledge engineer and handled only syntactically by the interpreters, they sometimes express information that can be properly exploited only with reference to a taxonomic background knowledge in order to capture unexpressed and underlying relationships among the concepts described. This is typical when the representation predicates are not purposely engineered but rather derive from the particular words found in a text.

  1. Analyzing forced unfolding of protein tandems by ordered variates, 1: Independent unfolding times.

    PubMed

    Bura, E; Klimov, D K; Barsegov, V

    2007-08-15

    Most of the mechanically active proteins are organized into tandems of identical repeats, (D)N, or heterogeneous tandems, D1-D2-...-DN. In current atomic force microscopy experiments, conformational transitions of protein tandems can be accessed by employing constant stretching force f (force-clamp) and by analyzing the recorded unfolding times of individual domains. Analysis of unfolding data for homogeneous tandems relies on the assumption that unfolding times are independent and identically distributed, and involves inference of the (parent) probability density of unfolding times from the histogram of the combined unfolding times. This procedure cannot be used to describe tandems characterized by interdomain interactions, or heteregoneous tandems. In this article, we introduce an alternative approach that is based on recognizing that the observed data are ordered, i.e., first, second, third, etc., unfolding times. The approach is exemplified through the analysis of unfolding times for a computer model of the homogeneous and heterogeneous tandems, subjected to constant force. We show that, in the experimentally accessible range of stretching forces, the independent and identically distributed assumption may not hold. Specifically, the uncorrelated unfolding transitions of individual domains at lower force may become correlated (dependent) at elevated force levels. The proposed formalism can be used in atomic force microscopy experiments to infer the unfolding time distributions of individual domains from experimental histograms of ordered unfolding times, and it can be extended to analyzing protein tandems that exhibit interdomain interactions.

  2. Reflecting Solutions of High Order Elliptic Differential Equations in Two Independent Variables Across Analytic Arcs. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Carleton, O.

    1972-01-01

    Consideration is given specifically to sixth order elliptic partial differential equations in two independent real variables x, y such that the coefficients of the highest order terms are real constants. It is assumed that the differential operator has distinct characteristics and that it can be factored as a product of second order operators. By analytically continuing into the complex domain and using the complex characteristic coordinates of the differential equation, it is shown that its solutions, u, may be reflected across analytic arcs on which u satisfies certain analytic boundary conditions. Moreover, a method is given whereby one can determine a region into which the solution is extensible. It is seen that this region of reflection is dependent on the original domain of difinition of the solution, the arc and the coefficients of the highest order terms of the equation and not on any sufficiently small quantities; i.e., the reflection is global in nature. The method employed may be applied to similar differential equations of order 2n.

  3. Development of Boundary Condition Independent Reduced Order Thermal Models using Proper Orthogonal Decomposition

    NASA Astrophysics Data System (ADS)

    Raghupathy, Arun; Ghia, Karman; Ghia, Urmila

    2008-11-01

    Compact Thermal Models (CTM) to represent IC packages has been traditionally developed using the DELPHI-based (DEvelopment of Libraries of PHysical models for an Integrated design) methodology. The drawbacks of this method are presented, and an alternative method is proposed. A reduced-order model that provides the complete thermal information accurately with less computational resources can be effectively used in system level simulations. Proper Orthogonal Decomposition (POD), a statistical method, can be used to reduce the order of the degree of freedom or variables of the computations for such a problem. POD along with the Galerkin projection allows us to create reduced-order models that reproduce the characteristics of the system with a considerable reduction in computational resources while maintaining a high level of accuracy. The goal of this work is to show that this method can be applied to obtain a boundary condition independent reduced-order thermal model for complex components. The methodology is applied to the 1D transient heat equation.

  4. The mitochondrial genomes of Amphiascoides atopus and Schizopera knabeni (Harpacticoida: Miraciidae) reveal similarities between the copepod orders Harpacticoida and Poecilostomatoida.

    PubMed

    Easton, Erin E; Darrow, Emily M; Spears, Trisha; Thistle, David

    2014-03-15

    Members of subclass Copepoda are abundant, diverse, and-as a result of their variety of ecological roles in marine and freshwater environments-important, but their phylogenetic interrelationships are unclear. Recent studies of arthropods have used gene arrangements in the mitochondrial (mt) genome to infer phylogenies, but for copepods, only seven complete mt genomes have been published. These data revealed several within-order and few among-order similarities. To increase the data available for comparisons, we sequenced the complete mt genome (13,831base pairs) of Amphiascoides atopus and 10,649base pairs of the mt genome of Schizopera knabeni (both in the family Miraciidae of the order Harpacticoida). Comparison of our data to those for Tigriopus japonicus (family Harpacticidae, order Harpacticoida) revealed similarities in gene arrangement among these three species that were consistent with those found within and among families of other copepod orders. Comparison of the mt genomes of our species with those known from other copepod orders revealed the arrangement of mt genes of our Harpacticoida species to be more similar to that of Sinergasilus polycolpus (order Poecilostomatoida) than to that of T. japonicus. The similarities between S. polycolpus and our species are the first to be noted across the boundaries of copepod orders and support the possibility that mt-gene arrangement might be used to infer copepod phylogenies. We also found that our two species had extremely truncated transfer RNAs and that gene overlaps occurred much more frequently than has been reported for other copepod mt genomes.

  5. The company they keep: Background similarity influences transfer of aftereffects from second- to first-order stimuli

    PubMed Central

    Qian, Ning; Dayan, Peter

    2013-01-01

    A wealth of studies has found that adapting to second-order visual stimuli has little effect on the perception of first-order stimuli. This is physiologically and psychologically troubling, since many cells show similar tuning to both classes of stimuli, and since adapting to first-order stimuli leads to aftereffects that do generalize to second-order stimuli. Focusing on high-level visual stimuli, we recently proposed the novel explanation that the lack of transfer arises partially from the characteristically different backgrounds of the two stimulus classes. Here, we consider the effect of stimulus backgrounds in the far more prevalent, lower-level, case of the orientation tilt aftereffect. Using a variety of first- and second-order oriented stimuli, we show that we could increase or decrease both within- and cross-class adaptation aftereffects by increasing or decreasing the similarity of the otherwise apparently uninteresting or irrelevant backgrounds of adapting and test patterns. Our results suggest that similarity between background statistics of the adapting and test stimuli contributes to low-level visual adaptation, and that these backgrounds are thus not discarded by visual processing but provide contextual modulation of adaptation. Null cross-adaptation aftereffects must also be interpreted cautiously. These findings reduce the apparent inconsistency between psychophysical and neurophysiological data about first- and second-order stimuli. PMID:23732217

  6. Similarities between third and fourth-order stratigraphic sequences: An example from the Permian Upper San Andres: Last Chance Canyon, Guadalupe Mountains, New Mexico

    SciTech Connect

    Sonnenfeld, M.D. )

    1990-05-01

    The upper San Andres/Cherry Canyon tongue in Last Chance constitutes a seismic-scale, unconformity bounded (third-order) depositional sequence containing mixed carbonate and siliciclastic lithologies deposited in intertidal through toe-of-slope environments. This sequence is composed of more than 12 clinoform packages that are smaller scale , higher frequency (fourth-order) depositional units or parasequences. Although shelf parasequences are asymmetric because flooding surfaces are coincident with maximum regressive surfaces, slope parasequences are relatively symmetric because transgressive deposits separate these two key surfaces. Slope parasequences within the highstand systems tract have bounding surfaces, stratal geometries, facies distributions, and siliciclastic/carbonate interrelationships that show similarities, independent of scale, to the lowstand, transgressive, and highstand systems tracts constituting the third-order sequence. Erosional surfaces and intermittent turbidite-filled channels form the basal portion of slope parasequences. Waning rates of siliciclastic sedimentation from suspension resulted in a basinally restricted, bioturbated sandstone wedge. Bedding planes within the wedge onlap the underlying parasequence boundary. These fourth-order geometries are similar to those of the third-order lowstand through transgressive systems tracts. The sandy wedge is capped by a transgressive surface. This surface is sporadically colonized by sponge-brachiopod communities, which are fourth-order analogs to the larger crinoid-bryozoan bioherms and brachiopod-sponge reefs developed on the third-order maximum flooding surface. Prograding fusulinid shoals downlap the fourth-order wedge, have fourth- and fifth-order toplap surfaces, and may be capped by regressive shelf sands. This mixed lithology package is a fourth-order analog to the third-order highstand systems tract.

  7. The procedural learning of action order is independent of temporal learning.

    PubMed

    Shin, Jacqueline C

    2008-07-01

    How does learning the timing of actions influence our ability to learn the order of actions? A sequence of responses cued by spatial stimuli was learned in a serial reaction time task where the response-to-stimulus intervals (RSIs) were random, constant, or followed a fixed sequence. In this final sequenced-RSI condition, the response and RSI sequences were consistently matched in phase and could be integrated into a common sequence representation. The main result was that the response sequence was learned to a similar degree in all RSI training conditions, indicating that neither the predictability of RSIs nor the integration of the phase-matched response and timing sequences benefited learning of the response sequence. Nevertheless, temporal learning and integration speeded up performance without strengthening the representation of response order.

  8. eMatchSite: Sequence Order-Independent Structure Alignments of Ligand Binding Pockets in Protein Models

    PubMed Central

    Brylinski, Michal

    2014-01-01

    Detecting similarities between ligand binding sites in the absence of global homology between target proteins has been recognized as one of the critical components of modern drug discovery. Local binding site alignments can be constructed using sequence order-independent techniques, however, to achieve a high accuracy, many current algorithms for binding site comparison require high-quality experimental protein structures, preferably in the bound conformational state. This, in turn, complicates proteome scale applications, where only various quality structure models are available for the majority of gene products. To improve the state-of-the-art, we developed eMatchSite, a new method for constructing sequence order-independent alignments of ligand binding sites in protein models. Large-scale benchmarking calculations using adenine-binding pockets in crystal structures demonstrate that eMatchSite generates accurate alignments for almost three times more protein pairs than SOIPPA. More importantly, eMatchSite offers a high tolerance to structural distortions in ligand binding regions in protein models. For example, the percentage of correctly aligned pairs of adenine-binding sites in weakly homologous protein models is only 4–9% lower than those aligned using crystal structures. This represents a significant improvement over other algorithms, e.g. the performance of eMatchSite in recognizing similar binding sites is 6% and 13% higher than that of SiteEngine using high- and moderate-quality protein models, respectively. Constructing biologically correct alignments using predicted ligand binding sites in protein models opens up the possibility to investigate drug-protein interaction networks for complete proteomes with prospective systems-level applications in polypharmacology and rational drug repositioning. eMatchSite is freely available to the academic community as a web-server and a stand-alone software distribution at http://www.brylinski.org/ematchsite. PMID

  9. Independently founded populations of Sclerotinia sclerotiorum from a tropical and a temperate region have similar genetic structure

    PubMed Central

    2017-01-01

    Sclerotinia sclerotiorum populations from tropical agricultural zones have been suggested to be more variable compared to those from temperate zones. However, no data were available comparing populations from both zones using the same set of markers. In this study, we compared S. sclerotiorum populations from the United States of America (USA, temperate) and southeast Brazil (tropical) using the frequency of mycelial compatibility groups (MCGs) and 13 microsatellite (SSR) markers. Populations were sourced from diseased plants within leguminous crops in New York, USA (NY; n = 78 isolates), and Minas Gerais State, Brazil (MG; n = 109). Twenty MCGs were identified in NY and 14 were previously reported in MG. The effective number of genotypes based on Hill’s number of order 0, which corresponded to the number of multilocus genotypes (MLGs) were 22 (95% CI = 15.6–28.4) and 24 (95% CI = 18.9–29.1) in NY and MG, respectively. Clonal fractions of MLGs were 71.8% (NY) and 78.0% (MG). The effective number of genotypes based on Hill’s number of orders 1 and 2 in NY were 8.9 (95% CI = 5.2–12.6) and 4.4 (95% CI = 2.6–6.1), respectively. For MG these indices were 11.4 (95% CI = 8.7–14.1) and 7.1 (95% CI = 5.1–9.0), respectively. There were no significant differences of allelic richness, private allelic richness, gene diversity, effective number of alleles and genotype evenness between the NY and MG populations. The populations were differentiated, with 29% of total variance attributed to differences between them and G''ST and Jost’s D indices higher than 0.50. Cluster analysis revealed dissimilarity higher than 80% among most MLGs from both populations. Different alleles segregated in the populations but both had similar levels of genotypic variability. PMID:28296968

  10. Independently founded populations of Sclerotinia sclerotiorum from a tropical and a temperate region have similar genetic structure.

    PubMed

    Lehner, Miller S; de Paula Júnior, Trazilbo J; Del Ponte, Emerson M; Mizubuti, Eduardo S G; Pethybridge, Sarah J

    2017-01-01

    Sclerotinia sclerotiorum populations from tropical agricultural zones have been suggested to be more variable compared to those from temperate zones. However, no data were available comparing populations from both zones using the same set of markers. In this study, we compared S. sclerotiorum populations from the United States of America (USA, temperate) and southeast Brazil (tropical) using the frequency of mycelial compatibility groups (MCGs) and 13 microsatellite (SSR) markers. Populations were sourced from diseased plants within leguminous crops in New York, USA (NY; n = 78 isolates), and Minas Gerais State, Brazil (MG; n = 109). Twenty MCGs were identified in NY and 14 were previously reported in MG. The effective number of genotypes based on Hill's number of order 0, which corresponded to the number of multilocus genotypes (MLGs) were 22 (95% CI = 15.6-28.4) and 24 (95% CI = 18.9-29.1) in NY and MG, respectively. Clonal fractions of MLGs were 71.8% (NY) and 78.0% (MG). The effective number of genotypes based on Hill's number of orders 1 and 2 in NY were 8.9 (95% CI = 5.2-12.6) and 4.4 (95% CI = 2.6-6.1), respectively. For MG these indices were 11.4 (95% CI = 8.7-14.1) and 7.1 (95% CI = 5.1-9.0), respectively. There were no significant differences of allelic richness, private allelic richness, gene diversity, effective number of alleles and genotype evenness between the NY and MG populations. The populations were differentiated, with 29% of total variance attributed to differences between them and G''ST and Jost's D indices higher than 0.50. Cluster analysis revealed dissimilarity higher than 80% among most MLGs from both populations. Different alleles segregated in the populations but both had similar levels of genotypic variability.

  11. Opposing effects of phonological similarity on item and order memory of words and nonwords in the serial recall task.

    PubMed

    Lian, Arild; Karlsen, Paul Johan; Eriksen, Thor Birger

    2004-05-01

    This study shows that the classical phonological similarity effect (PSE) in immediate serial recall is critically affected by the lexicality of list items, the type of phonological similarity involved, and the scoring procedure. PSE was present in the serial recall score when phonologically distinct words were compared to words that share the middle vowel and end consonant (rhyming lists). PSE was absent in the serial recall score when phonologically distinct words were compared to words that share the initial and final consonants (consonant frame lists). There was a reversal of PSE in serial recall of nonwords when comparing distinct lists to both types of similar lists. Recall accuracy on the other hand was higher for distinct lists regardless of lexicality. Item errors dominated in relation to order errors in the case of nonwords, whereas order errors dominated in relation to item errors in the case of words. Furthermore, order errors were more common for phonologically similar lists, whereas item errors were more common for phonologically distinct lists. This may be the result of intra-list and inter-list interference, respectively. The dominance of the former error type may cause a classical PSE, whereas the dominance of the latter error type may cause a reversal of PSE. Finally, an item identification task yielded no evidence of an association between intra-list interference and discriminability of items in a list.

  12. 77 FR 52137 - Proposed Order and Request for Comment on a Petition From Certain Independent System Operators...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-28

    ... Order Under Section 4(c) of the Commodity Exchange Act by ISO New England Inc.; In the Matter of the... include three RTOs (Midwest Independent Transmission System Operator Inc. (``MISO''); ISO New England, Inc. (``ISO NE''); and PJM Interconnection, L.L.C. (``PJM'')), and two ISOs (California Independent...

  13. Multiple independent origins of mitochondrial control region duplications in the order Psittaciformes

    PubMed Central

    Schirtzinger, Erin E.; Tavares, Erika S.; Gonzales, Lauren A.; Eberhard, Jessica R.; Miyaki, Cristina Y.; Sanchez, Juan J.; Hernandez, Alexis; Müeller, Heinrich; Graves, Gary R.; Fleischer, Robert C.; Wright, Timothy F.

    2012-01-01

    Mitochondrial genomes are generally thought to be under selection for compactness, due to their small size, consistent gene content, and a lack of introns or intergenic spacers. As more animal mitochondrial genomes are fully sequenced, rearrangements and partial duplications are being identified with increasing frequency, particularly in birds (Class Aves). In this study, we investigate the evolutionary history of mitochondrial control region states within the avian order Psittaciformes (parrots and cockatoos). To this aim, we reconstructed a comprehensive multi-locus phylogeny of parrots, used PCR of three diagnostic fragments to classify the mitochondrial control region state as single or duplicated, and mapped these states onto the phylogeny. We further sequenced 44 selected species to validate these inferences of control region state. Ancestral state reconstruction using a range of weighting schemes identified six independent origins of mitochondrial control region duplications within Psittaciformes. Analysis of sequence data showed that varying levels of mitochondrial gene and tRNA homology and degradation were present within a given clade exhibiting duplications. Levels of divergence between control regions within an individual varied from 0–10.9% with the differences occurring mainly between 51 and 225 nucleotides 3′ of the goose hairpin in domain I. Further investigations into the fates of duplicated mitochondrial genes, the potential costs and benefits of having a second control region, and the complex relationship between evolutionary rates, selection, and time since duplication are needed to fully explain these patterns in the mitochondrial genome. PMID:22543055

  14. Adjective-noun order as representational structure: native-language grammar influences perception of similarity and recognition memory.

    PubMed

    Mata, André; Percy, Elise J; Sherman, Steven J

    2014-02-01

    This article describes two experiments linking native-language grammar rules with implications for perception of similarity and recognition memory. In prenominal languages (e.g., English), adjectives usually precede nouns, whereas in postnominal languages (e.g., Portuguese), nouns usually precede adjectives. We explored the influence of such rules upon similarity judgments about, and recognition of, objects with multiple category attributes (one nominal attribute and one adjectival attribute). The results supported the hypothesized primacy effect of native-language word order such that nouns generally carried more weight for Portuguese speakers than for English speakers. This pattern was observed for judgments of similarity (i.e., Portuguese speakers tended to judge objects that shared a noun-designated attribute as more similar than did English speakers), as well as for false alarms in recognition memory (i.e., Portuguese speakers tended to falsely recognize more objects if they possessed a familiar noun attribute, relative to English speakers). The implications of such linguistic effects for the cognition of similarity and memory are discussed.

  15. Mutation-order divergence by sexual selection: diversification of sexual signals in similar environments as a first step in speciation.

    PubMed

    Mendelson, Tamra C; Martin, Michael D; Flaxman, Samuel M

    2014-09-01

    The origin of species remains a central question, and recent research focuses on the role of ecological differences in promoting speciation. Ecological differences create opportunities for divergent selection (i.e. 'ecological' speciation), a Darwinian hypothesis that hardly requires justification. In contrast, 'mutation-order' speciation proposes that, instead of adapting to different environments, populations find different ways to adapt to similar environments, implying that speciation does not require ecological differences. This distinction is critical as it provides an alternative hypothesis to the prevailing view that ecological differences drive speciation. Speciation by sexual selection lies at the centre of debates about the importance of ecological differences in promoting speciation; here, we present verbal and mathematical models of mutation-order divergence by sexual selection. We develop three general cases and provide a two-locus population genetic model for each. Results indicate that alternative secondary sexual traits can fix in populations that initially experience similar natural and sexual selection and that divergent traits and preferences can remain stable in the face of low gene flow. This stable divergence can facilitate subsequent divergence that completes or reinforces speciation. We argue that a mutation-order process could explain widespread diversity in secondary sexual traits among closely related, allopatric species.

  16. An integral-factorized implementation of the driven similarity renormalization group second-order multireference perturbation theory.

    PubMed

    Hannon, Kevin P; Li, Chenyang; Evangelista, Francesco A

    2016-05-28

    We report an efficient implementation of a second-order multireference perturbation theory based on the driven similarity renormalization group (DSRG-MRPT2) [C. Li and F. A. Evangelista, J. Chem. Theory Comput. 11, 2097 (2015)]. Our implementation employs factorized two-electron integrals to avoid storage of large four-index intermediates. It also exploits the block structure of the reference density matrices to reduce the computational cost to that of second-order Møller-Plesset perturbation theory. Our new DSRG-MRPT2 implementation is benchmarked on ten naphthyne isomers using basis sets up to quintuple-ζ quality. We find that the singlet-triplet splittings (ΔST) of the naphthyne isomers strongly depend on the equilibrium structures. For a consistent set of geometries, the ΔST values predicted by the DSRG-MRPT2 are in good agreements with those computed by the reduced multireference coupled cluster theory with singles, doubles, and perturbative triples.

  17. The Ordering Challenge: An Online Game to Introduce Independent Demand Inventory Concepts

    ERIC Educational Resources Information Center

    Meyer, Brad C.; Bishop, Debra S.

    2011-01-01

    Students are put in the role of a manager who watches inventory levels decrease and must order at the right time and in the right quantity to minimize costs. This interactive game requires the students to race against time and has levels of increasing difficulty. It introduces the students to the concepts of holding cost, ordering cost, backlog…

  18. The Ordering Challenge: An Online Game to Introduce Independent Demand Inventory Concepts

    ERIC Educational Resources Information Center

    Meyer, Brad C.; Bishop, Debra S.

    2011-01-01

    Students are put in the role of a manager who watches inventory levels decrease and must order at the right time and in the right quantity to minimize costs. This interactive game requires the students to race against time and has levels of increasing difficulty. It introduces the students to the concepts of holding cost, ordering cost, backlog…

  19. The apparent permeabilities of Caco-2 cells to marketed drugs: magnitude, and independence from both biophysical properties and endogenite similarities

    PubMed Central

    O’Hagan, Steve

    2015-01-01

    We bring together fifteen, nonredundant, tabulated collections (amounting to 696 separate measurements) of the apparent permeability (Papp) of Caco-2 cells to marketed drugs. While in some cases there are some significant interlaboratory disparities, most are quite minor. Most drugs are not especially permeable through Caco-2 cells, with the median Papp value being some 16 ⋅ 10−6 cm s−1. This value is considerably lower than those (1,310 and 230 ⋅ 10−6 cm s−1) recently used in some simulations that purported to show that Papp values were too great to be transporter-mediated only. While these values are outliers, all values, and especially the comparatively low values normally observed, are entirely consistent with transporter-only mediated uptake, with no need to invoke phospholipid bilayer diffusion. The apparent permeability of Caco-2 cells to marketed drugs is poorly correlated with either simple biophysical properties, the extent of molecular similarity to endogenous metabolites (endogenites), or any specific substructural properties. In particular, the octanol:water partition coefficient, logP, shows negligible correlation with Caco-2 permeability. The data are best explained on the basis that most drugs enter (and exit) Caco-2 cells via a multiplicity of transporters of comparatively weak specificity. PMID:26618081

  20. Scopolamine and amphetamine produce similar decision-making deficits on a rat gambling task via independent pathways.

    PubMed

    Silveira, Mason M; Malcolm, Emma; Shoaib, Mohammed; Winstanley, Catharine A

    2015-03-15

    Disorders characterized by disturbed cholinergic signaling, such as schizophrenia, exhibit impaired performance on measures of real-world cost/benefit decision-making. Whether the cholinergic system contributes to the choice deficits observed is currently unknown. We therefore determined the effects of broad-acting agonists and antagonists at the nicotinic and muscarinic receptor on decision making, as measured by the rodent gambling task (rGT). Given the anatomical and functional connectivity of the cholinergic and dopaminergic systems, we also sought to modulate amphetamine's previously reported effect on rGT performance via the cholinergic system. Male rats were trained on the rGT, during which animals chose from four different options. The optimal strategy on the rGT is to favor options associated with smaller immediate rewards and less punishment/loss. Impulsive action was also measured by recording the number of premature responses made. Performance on the rGT was assessed following acute treatment with the muscarinic receptor agonist oxotremorine, the muscarinic receptor antagonist scopolamine, nicotine, and the nicotinic receptor antagonist mecamylamine. Similar to the effect produced by amphetamine, muscarinic receptor antagonism with scopolamine (0.1mg/kg) impaired decision making, albeit to a lesser degree. Prior muscarinic agonism with oxotremorine was unable to attenuate amphetamine's effects on rGT performance. Oxotremorine, nicotine, and mecamylamine did not affect the choice profile. We therefore conclude that modulation of the muscarinic, but not nicotinic, receptor system can affect decision making under conditions of risk and uncertainty. Such findings contribute to a broader understanding of the cognitive deficits observed in disorders in which cholinergic signaling is compromised.

  1. Structural Signatures of Enzyme Binding Pockets from Order-Independent Surface Alignment: A Study of Metalloendopeptidase and NAD Binding Proteins

    PubMed Central

    Dundas, Joe; Adamian, Larisa; Liang, Jie

    2011-01-01

    Detecting similarities between local binding surfaces can facilitate identification of enzyme binding sites, prediction of enzyme functions, as well as aid in our understanding of enzyme mechanisms. A challenging task is to construct a template of local surface characteristics for a specific enzyme function or binding activity, as the size and shape of binding surfaces of a biochemical function often varies. Here we introduce the concept of signature binding pockets, which captures information about preserved and varied atomic positions at multi-resolution levels. For proteins with complex enzyme binding and activity, multiple signatures arise naturally in our model, which form a signature basis set that characterize this class of proteins. Both signatures and signature basis set can be automatically constructed by a method called Solar (Signature Of Local Active Regions). This method is based on a sequence order independent alignment of computed binding surface pockets. Solar also provides a structure based multiple sequence fragment alignment (MSFA) to facilitate interpretation of computed signatures. For studying a family of evolutionary related proteins, we show that for metzincin metalloendopeptidase, which has a broad spectrum of substrate binding, signature and basis set pockets can be used to discriminate metzincins from other enzymes, to predict the subclass of enzyme functions, and to identify the specific binding surfaces. For studying unrelated proteins which have evolved to bind to the same NAD co-factor, signatures of NAD binding pockets can be constructed and can be used to predict NAD binding proteins and to locate NAD binding pockets. By measuring preservation ratio and location variation, our method can identify residues and atoms important for binding affinity and specificity. In both cases, we show that signatures and signature basis set reveal significant biological insight. PMID:21145898

  2. Independence of First- and Second-Order Memories in Newborn Rabbits

    ERIC Educational Resources Information Center

    Coureaud, Gerard; Languille, Solene; Joly, Virginie; Schaal, Benoist; Hars, Bernard

    2011-01-01

    The mammary pheromone promotes the acquisition of novel odorants (CS1) in newborn rabbits. Here, experiments pinpoint that CS1 becomes able to support neonatal learning of other odorants (CS2). We therefore evaluated whether these first- and second-order memories remained dependent after reactivation. Amnesia induced after CS2 recall selectively…

  3. Independence of First- and Second-Order Memories in Newborn Rabbits

    ERIC Educational Resources Information Center

    Coureaud, Gerard; Languille, Solene; Joly, Virginie; Schaal, Benoist; Hars, Bernard

    2011-01-01

    The mammary pheromone promotes the acquisition of novel odorants (CS1) in newborn rabbits. Here, experiments pinpoint that CS1 becomes able to support neonatal learning of other odorants (CS2). We therefore evaluated whether these first- and second-order memories remained dependent after reactivation. Amnesia induced after CS2 recall selectively…

  4. Evaluating the Applicability of Data-Driven Dietary Patterns to Independent Samples with a Focus on Measurement Tools for Pattern Similarity.

    PubMed

    Castelló, Adela; Buijsse, Brian; Martín, Miguel; Ruiz, Amparo; Casas, Ana M; Baena-Cañada, Jose M; Pastor-Barriuso, Roberto; Antolín, Silvia; Ramos, Manuel; Muñoz, Monserrat; Lluch, Ana; de Juan-Ferré, Ana; Jara, Carlos; Lope, Virginia; Jimeno, María A; Arriola-Arellano, Esperanza; Díaz, Elena; Guillem, Vicente; Carrasco, Eva; Pérez-Gómez, Beatriz; Vioque, Jesús; Pollán, Marina

    2016-12-01

    Diet is a key modifiable risk for many chronic diseases, but it remains unclear whether dietary patterns from one study sample are generalizable to other independent populations. The primary objective of this study was to assess whether data-driven dietary patterns from one study sample are applicable to other populations. The secondary objective was to assess the validity of two criteria of pattern similarity. Six dietary patterns-Western (n=3), Mediterranean, Prudent, and Healthy- from three published studies on breast cancer were reconstructed in a case-control study of 973 breast cancer patients and 973 controls. Three more internal patterns (Western, Prudent, and Mediterranean) were derived from this case-control study's own data. Applicability was assessed by comparing the six reconstructed patterns with the three internal dietary patterns, using the congruence coefficient (CC) between pattern loadings. In cases where any pair met either of two commonly used criteria for declaring patterns similar (CC ≥0.85 or a statistically significant [P<0.05] Pearson correlation), then the true similarity of those two dietary patterns was double-checked by comparing their associations to risk for breast cancer, to assess whether those two criteria of similarity are actually reliable. Five of the six reconstructed dietary patterns showed high congruence (CC >0.9) to their corresponding dietary pattern derived from the case-control study's data. Similar associations with risk for breast cancer were found in all pairs of dietary patterns that had high CC but not in all pairs of dietary patterns with statistically significant correlations. Similar dietary patterns can be found in independent samples. The P value of a correlation coefficient is less reliable than the CC as a criterion for declaring two dietary patterns similar. This study shows that diet scores based on a particular study are generalizable to other populations. Copyright © 2016 Academy of Nutrition and

  5. Time-Order Errors in Duration Judgment Are Independent of Spatial Positioning

    PubMed Central

    Harrison, Charlotte; Binetti, Nicola; Mareschal, Isabelle; Johnston, Alan

    2017-01-01

    Time-order errors (TOEs) occur when the discriminability between two stimuli are affected by the order in which they are presented. While TOEs have been studied since the 1860s, it is unknown whether the spatial properties of a stimulus will affect this temporal phenomenon. In this experiment, we asked whether perceived duration, or duration discrimination, might be influenced by whether two intervals in a standard two-interval method of constants paradigm were spatially overlapping in visual short-term memory. Two circular sinusoidal gratings (one standard and the other a comparison) were shown sequentially and participants judged which of the two was presented for a longer duration. The test stimuli were either spatially overlapping (in different spatial frames) or separate. Stimulus order was randomized between trials. The standard stimulus lasted 600 ms, and the test stimulus had one of seven possible values (between 300 and 900 ms). There were no overall significant differences observed between spatially overlapping and separate stimuli. However, in trials where the standard stimulus was presented second, TOEs were greater, and participants were significantly less sensitive to differences in duration. TOEs were also greater in conditions involving a saccade. This suggests there is an intrinsic memory component to two interval tasks in that the information from the first interval has to be stored; this is more demanding when the standard is presented in the second interval. Overall, this study suggests that while temporal information may be encoded in some spatial form, it is not dependent on visual short-term memory. PMID:28337162

  6. Robust data driven model order estimation for independent component analysis of FMRI data with low contrast to noise.

    PubMed

    Majeed, Waqas; Avison, Malcolm J

    2014-01-01

    Independent component analysis (ICA) has been successfully utilized for analysis of functional MRI (fMRI) data for task related as well as resting state studies. Although it holds the promise of becoming an unbiased data-driven analysis technique, a few choices have to be made prior to performing ICA, selection of a method for determining the number of independent components (nIC) being one of them. Choice of nIC has been shown to influence the ICA maps, and various approaches (mostly relying on information theoretic criteria) have been proposed and implemented in commonly used ICA analysis packages, such as MELODIC and GIFT. However, there has been no consensus on the optimal method for nIC selection, and many studies utilize arbitrarily chosen values for nIC. Accurate and reliable determination of true nIC is especially important in the setting where the signals of interest contribute only a small fraction of the total variance, i.e. very low contrast-to-noise ratio (CNR), and/or very focal response. In this study, we evaluate the performance of different model order selection criteria and demonstrate that the model order selected based upon bootstrap stability of principal components yields more reliable and accurate estimates of model order. We then demonstrate the utility of this fully data-driven approach to detect weak and focal stimulus-driven responses in real data. Finally, we compare the performance of different multi-run ICA approaches using pseudo-real data.

  7. Previous gestational diabetes is independently associated with increased carotid intima-media thickness, similarly to metabolic syndrome – a case control study

    PubMed Central

    2012-01-01

    Background Women with previous gestational diabetes mellitus (pGDM) face a higher risk of developing type 2 diabetes and, consequently, a higher cardiovascular risk. This study aimed to compare the carotid intima-media thickness (cIMT) from young women with pGDM to those with metabolic syndrome (MS) and to healthy controls (CG) to verify whether a past history of pGDM could be independently associated with increased cIMT. Methods This is a cross-sectional study performed in two academic referral centers. Seventy-nine women with pGDM, 30 women with MS, and 60 CG aged between 18 and 47 years were enrolled. They all underwent physical examination and had blood glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDLc), and triglycerides determined. The cIMT was measured by ultrasound in several carotid segments. The primary endpoint was cIMT and clinically relevant parameters included as predictors were: age, systolic blood pressure, waist, BMI, total cholesterol, LDLc, triglycerides, fasting glucose, previous history of GDM as a whole group, previous history of GDM without MS, presence of DM, presence of MS, and parity. Results cIMT was significantly higher in pGDM when compared to CG in all sites of measurements (P < 0.05) except for the right common carotid. The pGDM women showed similar cIMT measurements to MS in all sites of measurements, except for the left carotid bifurcation, where it was significantly higher than MS (P < 0.001). In a multivariate analysis which included classical cardiovascular risk factors and was adjusted for confounders, pGDM was shown to be independently associated with increased composite cIMT (P < 0.01). The pGDM without risk factors further showed similar cIMT to MS (P > 0.05) and an increased cIMT when compared to controls (P < 0.05). Conclusions Previous GDM was independently associated with increased composite cIMT in this young population, similarly to those with

  8. Robust Data Driven Model Order Estimation for Independent Component Analysis of fMRI Data with Low Contrast to Noise

    PubMed Central

    Majeed, Waqas; Avison, Malcolm J.

    2014-01-01

    Independent component analysis (ICA) has been successfully utilized for analysis of functional MRI (fMRI) data for task related as well as resting state studies. Although it holds the promise of becoming an unbiased data-driven analysis technique, a few choices have to be made prior to performing ICA, selection of a method for determining the number of independent components (nIC) being one of them. Choice of nIC has been shown to influence the ICA maps, and various approaches (mostly relying on information theoretic criteria) have been proposed and implemented in commonly used ICA analysis packages, such as MELODIC and GIFT. However, there has been no consensus on the optimal method for nIC selection, and many studies utilize arbitrarily chosen values for nIC. Accurate and reliable determination of true nIC is especially important in the setting where the signals of interest contribute only a small fraction of the total variance, i.e. very low contrast-to-noise ratio (CNR), and/or very focal response. In this study, we evaluate the performance of different model order selection criteria and demonstrate that the model order selected based upon bootstrap stability of principal components yields more reliable and accurate estimates of model order. We then demonstrate the utility of this fully data-driven approach to detect weak and focal stimulus-driven responses in real data. Finally, we compare the performance of different multi-run ICA approaches using pseudo-real data. PMID:24788636

  9. n-Order and maximum fuzzy similarity entropy for discrimination of signals of different complexity: Application to fetal heart rate signals.

    PubMed

    Zaylaa, Amira; Oudjemia, Souad; Charara, Jamal; Girault, Jean-Marc

    2015-09-01

    This paper presents two new concepts for discrimination of signals of different complexity. The first focused initially on solving the problem of setting entropy descriptors by varying the pattern size instead of the tolerance. This led to the search for the optimal pattern size that maximized the similarity entropy. The second paradigm was based on the n-order similarity entropy that encompasses the 1-order similarity entropy. To improve the statistical stability, n-order fuzzy similarity entropy was proposed. Fractional Brownian motion was simulated to validate the different methods proposed, and fetal heart rate signals were used to discriminate normal from abnormal fetuses. In all cases, it was found that it was possible to discriminate time series of different complexity such as fractional Brownian motion and fetal heart rate signals. The best levels of performance in terms of sensitivity (90%) and specificity (90%) were obtained with the n-order fuzzy similarity entropy. However, it was shown that the optimal pattern size and the maximum similarity measurement were related to intrinsic features of the time series. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Arrays of quasi-hexagonally ordered silica nanopillars with independently controlled areal density, diameter and height gradients

    NASA Astrophysics Data System (ADS)

    Özdemir, Burcin; Huang, Wenting; Plettl, Alfred; Ziemann, Paul

    2015-03-01

    A consecutive fabrication approach of independently tailored gradients of the topographical parameters distance, diameter and height in arrays of well-ordered nanopillars on smooth SiO2-Si-wafers is presented. For this purpose, previously reported preparation techniques are further developed and combined. First, self-assembly of Au-salt loaded micelles by dip-coating with computer-controlled pulling-out velocities and subsequent hydrogen plasma treatment produce quasi-hexagonally ordered, 2-dimensional arrays of Au nanoparticles (NPs) with unidirectional variations of the interparticle distances along the pulling direction between 50-120 nm. Second, the distance (or areal density) gradient profile received in this way is superimposed with a diameter-controlled gradient profile of the NPs applying a selective photochemical growth technique. For demonstration, a 1D shutter is used for locally defined UV exposure times to prepare Au NP size gradients varying between 12 and 30 nm. Third, these double-gradient NP arrangements serve as etching masks in a following reactive ion etching step delivering arrays of nanopillars. For height gradient generation, the etching time is locally controlled by applying a shutter made from Si wafer piece. Due to the high flexibility of the etching process, the preparation route works on various materials such as cover slips, silicon, silicon oxide, silicon nitride and silicon carbide.

  11. A gauge-independent zeroth-order regular approximation to the exact relativistic Hamiltonian--formulation and applications.

    PubMed

    Filatov, Michael; Cremer, Dieter

    2005-01-22

    A simple modification of the zeroth-order regular approximation (ZORA) in relativistic theory is suggested to suppress its erroneous gauge dependence to a high level of approximation. The method, coined gauge-independent ZORA (ZORA-GI), can be easily installed in any existing nonrelativistic quantum chemical package by programming simple one-electron matrix elements for the quasirelativistic Hamiltonian. Results of benchmark calculations obtained with ZORA-GI at the Hartree-Fock (HF) and second-order Moller-Plesset perturbation theory (MP2) level for dihalogens X(2) (X=F,Cl,Br,I,At) are in good agreement with the results of four-component relativistic calculations (HF level) and experimental data (MP2 level). ZORA-GI calculations based on MP2 or coupled-cluster theory with single and double perturbations and a perturbative inclusion of triple excitations [CCSD(T)] lead to accurate atomization energies and molecular geometries for the tetroxides of group VIII elements. With ZORA-GI/CCSD(T), an improved estimate for the atomization energy of hassium (Z=108) tetroxide is obtained.

  12. Molecular similarity and property similarity.

    PubMed

    Barbosa, Frédérique; Horvath, Dragos

    2004-01-01

    This paper reviews the main efforts undertaken up to date in order to understand, rationalize and apply the similarity principle (similar compounds=>similar properties) as a computational tool in modern drug discovery. The best suited mathematical expression of this classical working hypothesis of medicinal chemistry needs to be carefully chosen (out of the virtually infinite possible implementations in terms of molecular descriptors and molecular similarity metrics), in order to achieve an optimal validation of the hypothesis that molecules that are neighbors in the Structural Space will also display similar properties. This overview will show why no single "absolute" measure of molecular similarity can be conceived, and why molecular similarity scores should be considered tunable tools that need to be adapted to each problem to solve.

  13. Continuously tunable polarization-independent zeroth-order fiber comb filter based on polarization-diversity loop structure

    NASA Astrophysics Data System (ADS)

    Jung, Jaehoon; Lee, Yong Wook

    2017-04-01

    By selecting some optimal wave retarder combination (WRC) groups, we propose and experimentally implement a continuously tunable polarization-independent zeroth-order fiber comb filter based on a polarization-diversity loop structure. The selected WRC groups contain a set of two quarter-wave retarders (QWRs), a set of a QWR and a half-wave retarder (HWR), and a set of an HWR and a QWR. The filter was formed using a polarization beam splitter (PBS), one of the three selected WRC groups, and high birefringence fiber (HBF). One end of HBF was butt-coupled to the PBS so that its slow axis should be oriented at 45° for the horizontal axis of the PBS, and the other end was connected to the WRC group. Three kinds of comb filters were fabricated with the three selected WRC groups. Through theoretical analysis on light polarization conditions for continuous spectral tuning and filter transmittances, eight special azimuth angle sets of two wave retarders, which gave the transmittance function eight different phase shifts of 0 to -7 π/4 with a -π/4 step, were found for each WRC group. Theoretical prediction was verified by experimental demonstration. It was also confirmed that the filter could be continuously tuned by the appropriate control of wave retarders.

  14. Independence of interrupted coarsening on initial system order: ion-beam nanopatterning of amorphous versus crystalline silicon targets.

    PubMed

    Muñoz-García, J; Gago, R; Cuerno, R; Sánchez-García, J A; Redondo-Cubero, A; Castro, M; Vázquez, L

    2012-09-19

    Interrupted coarsening (IC) has recently been identified as an important feature for the dynamics of the typical length-scale in pattern-forming systems on surfaces. In practice, it can be beneficial to improve pattern ordering since it combines a certain degree of defect suppression with a limited increase in the typical pattern wavelength. However, little is known about its robustness with respect to changes in the preparation of the initial system for cases with potential applications. Working in the context of nano-scale pattern formation by ion-beam sputtering (IBS), we prove that IC properties do not depend on sample preparation. Specifically, interface dynamics under IBS is quantitatively compared on virgin amorphous and crystalline silicon surfaces, using 1 keV Ar(+) ions at normal incidence where nanodot pattern formation is triggered by concurrent co-deposition of Fe atoms during processing. Atomic force microscopy shows that dot patterns with similar spatial order and dynamics are obtained in both cases, underscoring the key dynamical role of the amorphous surface layer produced by irradiation. Both systems have been quantitatively described by an effective interface equation. We employ a new procedure based on the linear growth of the initial surface correlations to accurately estimate the equation coefficients. Such a method improves the predictive power of the interface equation with respect to previous studies and leads to a better description of the experimental pattern and its dynamical features.

  15. Antimicrobial preservatives induce aggregation of interferon alpha-2a: The order in which preservatives induce protein aggregation is independent of the protein

    PubMed Central

    Bis, Regina L.; Mallela, Krishna M.G.

    2014-01-01

    Antimicrobial preservatives (APs) are included in liquid multi-dose protein formulations to combat the growth of microbes and bacteria. These compounds have been shown to cause protein aggregation, which leads to serious immunogenic and toxic side-effects in patients. Our earlier work on a model protein cytochrome c (Cyt c) demonstrated that APs cause protein aggregation in a specific manner. The aim of this study is to validate the conclusions obtained from our model protein studies on a pharmaceutical protein. Interferon α-2a (IFNA2) is available as a therapeutic treatment for numerous immune-compromised disorders including leukemia and hepatitis c, and APs have been used in its multi-dose formulation. Similar to Cyt c, APs induced IFNA2 aggregation, demonstrated by the loss of soluble monomer and increase in solution turbidity. The extent of IFNA2 aggregation increased with the increase in AP concentration. IFNA2 aggregation also depended on the nature of AP, and followed the order m-cresol > phenol > benzyl alcohol > phenoxyethanol. This specific order exactly matched with that observed for the model protein Cyt c. These and previously published results on antibodies and other recombinant proteins suggest that the general mechanism by which APs induce protein aggregation may be independent of the protein. PMID:24974985

  16. Antimicrobial preservatives induce aggregation of interferon alpha-2a: the order in which preservatives induce protein aggregation is independent of the protein.

    PubMed

    Bis, Regina L; Mallela, Krishna M G

    2014-09-10

    Antimicrobial preservatives (APs) are included in liquid multi-dose protein formulations to combat the growth of microbes and bacteria. These compounds have been shown to cause protein aggregation, which leads to serious immunogenic and toxic side-effects in patients. Our earlier work on a model protein cytochrome c (Cyt c) demonstrated that APs cause protein aggregation in a specific manner. The aim of this study is to validate the conclusions obtained from our model protein studies on a pharmaceutical protein. Interferon α-2a (IFNA2) is available as a therapeutic treatment for numerous immune-compromised disorders including leukemia and hepatitis C, and APs have been used in its multi-dose formulation. Similar to Cyt c, APs induced IFNA2 aggregation, demonstrated by the loss of soluble monomer and increase in solution turbidity. The extent of IFNA2 aggregation increased with the increase in AP concentration. IFNA2 aggregation also depended on the nature of AP, and followed the order m-cresol>phenol>benzyl alcohol>phenoxyethanol. This specific order exactly matched with that observed for the model protein Cyt c. These and previously published results on antibodies and other recombinant proteins suggest that the general mechanism by which APs induce protein aggregation may be independent of the protein. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Interpersonal Congruency, Attitude Similarity, and Interpersonal Attraction

    ERIC Educational Resources Information Center

    Touhey, John C.

    1975-01-01

    As no experimental study has examined the effects of congruency on attraction, the present investigation orthogonally varied attitude similarity and interpersonal congruency in order to compare the two independent variables as determinants of interpersonal attraction. (Author/RK)

  18. Physicochemical, bioactive, and sensory properties of persimmon-based ice cream: technique for order preference by similarity to ideal solution to determine optimum concentration.

    PubMed

    Karaman, Safa; Toker, Ömer Said; Yüksel, Ferhat; Çam, Mustafa; Kayacier, Ahmed; Dogan, Mahmut

    2014-01-01

    In the present study, persimmon puree was incorporated into the ice cream mix at different concentrations (8, 16, 24, 32, and 40%) and some physicochemical (dry matter, ash, protein, pH, sugar, fat, mineral, color, and viscosity), textural (hardness, stickiness, and work of penetration), bioactive (antiradical activity and total phenolic content), and sensory properties of samples were investigated. The technique for order preference by similarity to ideal solution approach was used for the determination of optimum persimmon puree concentration based on the sensory and bioactive characteristics of final products. Increase in persimmon puree resulted in a decrease in the dry matter, ash, fat, protein contents, and viscosity of ice cream mix. Glucose, fructose, sucrose, and lactose were determined to be major sugars in the ice cream samples including persimmon and increase in persimmon puree concentration increased the fructose and glucose content. Better melting properties and textural characteristics were observed for the samples with the addition of persimmon. Magnesium, K, and Ca were determined to be major minerals in the samples and only K concentration increased with the increase in persimmon content. Bioactive properties of ice cream samples improved and, in general, acetone-water extracts showed higher bioactivity compared with ones obtained using methanol-water extracts. The technique for order preference by similarity to ideal solution approach showed that the most preferred sample was the ice cream containing 24% persimmon puree.

  19. Ordered mesoporous silica induces pH-independent supersaturation of the basic low solubility compound itraconazole resulting in enhanced transepithelial transport.

    PubMed

    Mellaerts, Randy; Mols, Raf; Kayaert, Pieterjan; Annaert, Pieter; Van Humbeeck, Jan; Van den Mooter, Guy; Martens, Johan A; Augustijns, Patrick

    2008-06-05

    The majority of innovative drug candidates are poorly water soluble and exhibit basic properties. This makes them highly dependent on the in vivo encountered acid-neutral pH sequence to achieve a sufficient dissolution and thus absorption. In this study, we evaluated the pH-independent generation of intraluminally induced supersaturation of the model compound itraconazole and its beneficial effect on the extent of absorption in the Caco-2 system and the rat in situ perfusion system. Local supersaturation was obtained by means of a solvent shift method and a novel formulation strategy based on ordered mesoporous silica (OMS) as a carrier. In vitro results evidenced that both methods were capable of creating a supersaturated state of itraconazole in fasted state simulated intestinal fluid (FaSSIF) when no preceding acidic dissolution was simulated. The extent of supersaturation exceeded 21.9 and 9.6 during at least 4h for the solvent shift method and OMS as a carrier, respectively. As compared to saturation conditions (0.09+/-0.01 microg), supersaturation induced by the solvent shift method as well as by the use of OMS increased transport across a Caco-2 cell monolayer more than 16-fold, resulting in the basolateral appearance of 2.20+/-0.29 microg and 1.46+/-0.03 microg itraconazole after 90 min, respectively. In the absence of an acid-neutral pH sequence, the performance of the marketed product Sporanox was inferior with total transport amounting to 0.12+/-0.03 microg after 90 min. Enhanced absorption was confirmed in the in situ perfusion model where OMS was able to boost total transport of itraconazole after 60 min from 0.03+/-0.01 nmol cm(-1) to 0.70+/-0.09 nmol cm(-1) compared to saturated equilibrium conditions in FaSSIF. The solid dosage form Sporanox again failed to achieve a similar extent of absorption enhancement (0.29+/-0.01 nmol cm(-1)). These findings suggest that intraluminal supersaturation can be created by the use of OMS and that preceding

  20. 78 FR 19879 - Final Order in Response to a Petition From Certain Independent System Operators and Regional...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-02

    ... INFORMATION CONTACT: Robert B. Wasserman, Chief Counsel, 202-418-5092, rwasserman@cftc.gov , Laura Astrada... Futures Trading Commission, Three Lafayette Centre, 1151 21st Street NW., Washington, DC 20581. SUPPLEMENTARY INFORMATION: Table of Contents I. Relevant Dodd-Frank Provisions II. Background--Proposed Order A...

  1. Independent ordering of two interpenetrating magnetic sublattices in the double perovskite Sr2CoOsO6.

    PubMed

    Morrow, Ryan; Mishra, Rohan; Restrepo, Oscar D; Ball, Molly R; Windl, Wolfgang; Wurmehl, Sabine; Stockert, Ulrike; Büchner, Bernd; Woodward, Patrick M

    2013-12-18

    The insulating, fully ordered, double perovskite Sr2CoOsO6 undergoes two magnetic phase transitions. The Os(VI) ions order antiferromagnetically with a propagation vector k = (1/2, 1/2, 0) below TN1 = 108 K, while the high-spin Co(II) ions order antiferromagnetically with a propagation vector k = (1/2, 0, 1/2) below TN2 = 70 K. Ordering of the Os(VI) spins is accompanied by a structural distortion from tetragonal I4/m symmetry to monoclinic I2/m symmetry, which reduces the frustration of the face centered cubic lattice of Os(VI) ions. Density functional theory calculations show that the long-range Os-O-Co-O-Os and Co-O-Os-O-Co superexchange interactions are considerably stronger than the shorter Os-O-Co interactions. The poor energetic overlap between the 3d orbitals of Co and the 5d orbitals of Os appears to be responsible for this unusual inversion in the strength of short and long-range superexchange interactions.

  2. 2, 2'- and 4, 4'-Cyanines are transporter-independent in vitro dopaminergic toxins with the specificity and mechanism of toxicity similar to MPP⁺.

    PubMed

    Kadigamuwa, Chamila C; Le, Viet Q; Wimalasena, Kandatege

    2015-11-01

    Specific uptake through dopamine transporter followed by the inhibition of the mitochondrial complex-I have been accepted as the cause of the specific dopaminergic toxicity of 1-methyl-4-phenylpyridinium (MPP(+) ). However, MPP(+) is taken up into many cell types through other transporters, suggesting that, in addition to the efficient uptake, intrinsic vulnerability of dopaminergic cells may also contribute to their high sensitivity to MPP(+) and similar toxins. To test this possibility, two simple cyanines were employed in a comparative study based on their unique characteristics and structural similarity to MPP(+) . Here, we show that they freely accumulate in dopaminergic (MN9D and SH-SY5Y) as well as in liver (HepG2) cells, but are specifically and highly toxic to dopaminergic cells with IC50s in the range of 50-100 nM, demonstrating that they are about 1000-fold more toxic than MPP(+) under similar experimental conditions. They cause mitochondrial depolarization non-specifically, but increase the reactive oxygen species specifically in dopaminergic cells leading to the apoptotic cell death parallel to MPP(+) . These and other findings suggest that the specific dopaminergic toxicity of these cyanines is due to the inherent vulnerability of dopaminergic cells toward mitochondrial toxins that lead to the excessive production of reactive oxygen species. Therefore, the specific dopaminergic toxicity of MPP(+) must also be, at least partly, due to the specific vulnerability of dopaminergic neurons. Thus, these cyanines could be stronger in vivo dopaminergic toxins than MPP(+) and their in vivo toxicities must be evaluated. Here, we show that cationic lipophilic cyanines with structural similarity to 1-methyl-4-phenylpyridinium (MPP(+) ) freely accumulate non-specifically, but only toxic to dopaminergic cells. They are 1000-fold more toxic than MPP(+) under similar conditions. They cause mitochondrial depolarization non-specifically, but increase the ROS

  3. Artifact Free and Detection Profile Independent Higher Order Fluorescence Correlation Spectroscopy for Microsecond Resolved Kinetics. 2. Mixtures and Reactions.

    PubMed

    Abdollah-Nia, Farshad; Gelfand, Martin P; Van Orden, Alan K

    2017-02-09

    Fluorescence correlation spectroscopy (FCS) is a primary tool in the time-resolved analysis of non-reacting or reacting molecules in solution, based on fluorescence intensity fluctuations. However, conventional FCS alone is insufficient for complete determination of reaction or mixture parameters. In an accompanying article, a technique for computation of artifact-free higher-order correlations with microsecond time resolution was described. Here, we demonstrate applications of the technique to analyze systems of fast and slow reactions. As an example of slow- or non-reacting systems, the technique is applied to resolve two-component mixtures of labeled oligonucleotides. Next, the protonation reaction of fluorescein isothiocyanate (FITC) in phosphate buffer is analyzed as an example of fast reactions (relaxation time <1 μs ). By reference to an (apparent) non-reacting system, the simple factorized form of cumulant-based higher-order correlations is exploited to remove the dependence on the molecular detection function (MDF). Therefore, there is no need to model and characterize the experimental MDF, and the precision and the accuracy of the technique are enhanced. It is verified that higher-order correlation analysis enables complete and simultaneous determination of number and brightness parameters of mixing or reacting molecules, the reaction relaxation time, and forward and reverse reaction rates.

  4. Comparison of Dissolution Similarity Assessment Methods for Products with Large Variations: f2 Statistics and Model-Independent Multivariate Confidence Region Procedure for Dissolution Profiles of Multiple Oral Products.

    PubMed

    Yoshida, Hiroyuki; Shibata, Hiroko; Izutsu, Ken-Ichi; Goda, Yukihiro

    2017-01-01

    The current Japanese Ministry of Health Labour and Welfare (MHLW)'s Guideline for Bioequivalence Studies of Generic Products uses averaged dissolution rates for the assessment of dissolution similarity between test and reference formulations. This study clarifies how the application of model-independent multivariate confidence region procedure (Method B), described in the European Medical Agency and U.S. Food and Drug Administration guidelines, affects similarity outcomes obtained empirically from dissolution profiles with large variations in individual dissolution rates. Sixty-one datasets of dissolution profiles for immediate release, oral generic, and corresponding innovator products that showed large variation in individual dissolution rates in generic products were assessed on their similarity by using the f2 statistics defined in the MHLW guidelines (MHLW f2 method) and two different Method B procedures, including a bootstrap method applied with f2 statistics (BS method) and a multivariate analysis method using the Mahalanobis distance (MV method). The MHLW f2 and BS methods provided similar dissolution similarities between reference and generic products. Although a small difference in the similarity assessment may be due to the decrease in the lower confidence interval for expected f2 values derived from the large variation in individual dissolution rates, the MV method provided results different from those obtained through MHLW f2 and BS methods. Analysis of actual dissolution data for products with large individual variations would provide valuable information towards an enhanced understanding of these methods and their possible incorporation in the MHLW guidelines.

  5. Increasing the contrast of the brain MR FLAIR images using fuzzy membership functions and structural similarity indices in order to segment MS lesions.

    PubMed

    Bijar, Ahmad; Khayati, Rasoul; Peñalver Benavent, Antonio

    2013-01-01

    Segmentation is an important step for the diagnosis of multiple sclerosis (MS). This paper presents a new approach to the fully automatic segmentation of MS lesions in Fluid Attenuated Inversion Recovery (FLAIR) Magnetic Resonance (MR) images. With the aim of increasing the contrast of the FLAIR MR images with respect to the MS lesions, the proposed method first estimates the fuzzy memberships of brain tissues (i.e., the cerebrospinal fluid (CSF), the normal-appearing brain tissue (NABT), and the lesion). The procedure for determining the fuzzy regions of their member functions is performed by maximizing fuzzy entropy through Genetic Algorithm. Research shows that the intersection points of the obtained membership functions are not accurate enough to segment brain tissues. Then, by extracting the structural similarity (SSIM) indices between the FLAIR MR image and its lesions membership image, a new contrast-enhanced image is created in which MS lesions have high contrast against other tissues. Finally, the new contrast-enhanced image is used to segment MS lesions. To evaluate the result of the proposed method, similarity criteria from all slices from 20 MS patients are calculated and compared with other methods, which include manual segmentation. The volume of segmented lesions is also computed and compared with Gold standard using the Intraclass Correlation Coefficient (ICC) and paired samples t test. Similarity index for the patients with small lesion load, moderate lesion load and large lesion load was 0.7261, 0.7745 and 0.8231, respectively. The average overall similarity index for all patients is 0.7649. The t test result indicates that there is no statistically significant difference between the automatic and manual segmentation. The validated results show that this approach is very promising.

  6. Next-to-leading order QCD corrections to the single top quark production via model-independent tqg flavor-changing neutral-current couplings at hadron colliders

    SciTech Connect

    Gao Jun; Li Chongsheng; Zhang Jiajun; Zhu Huaxing

    2009-12-01

    We present the calculations of the complete next-to-leading order (NLO) QCD effects on the single top productions induced by model-independent tqg flavor-changing neutral-current couplings at hadron colliders. Our results show that, for the tcg coupling, the NLO QCD corrections can enhance the total cross sections by about 60% and 30%, and for the tug coupling by about 50% and 20% at the Tevatron and LHC, respectively, which means that the NLO corrections can increase the experimental sensitivity to the flavor-changing neutral-current couplings by about 10%-30%. Moreover, the NLO corrections reduce the dependence of the total cross sections on the renormalization or factorization scale significantly, which lead to increased confidence on the theoretical predictions. Besides, we also evaluate the NLO corrections to several important kinematic distributions, and find that for most of them the NLO corrections are almost the same and do not change the shape of the distributions.

  7. Higher-order scheme-independent series expansions of γψ ¯ψ ,IR and βIR' in conformal field theories

    NASA Astrophysics Data System (ADS)

    Ryttov, Thomas A.; Shrock, Robert

    2017-05-01

    We study a vectorial asymptotically free gauge theory, with gauge group G and Nf massless fermions in a representation R of this group, that exhibits an infrared (IR) zero in its beta function, β , at the coupling α =αIR in the non-Abelian Coulomb phase. For general G and R , we calculate the scheme-independent series expansions of (i) the anomalous dimension of the fermion bilinear, γψ ¯ ψ ,IR , to O (Δf4) and (ii) the derivative β'=d β /d α , to O (Δf5) , both evaluated at αIR, where Δf is an Nf-dependent expansion variable. These are the highest orders to which these expansions have been calculated. We apply these general results to theories with G =SU (Nc) and R equal to the fundamental, adjoint, and symmetric and antisymmetric rank-2 tensor representations. It is shown that for all of these representations, γψ ¯ ψ ,IR , calculated to the order Δfp , with 1 ≤p ≤4 , increases monotonically with decreasing Nf and, for fixed Nf, is a monotonically increasing function of p . Comparisons of our scheme-independent calculations of γψ ¯ ψ ,IR and βIR' are made with our earlier higher n -loop values of these quantities, and with lattice measurements. For R =F , we present results for the limit Nc→∞ and Nf→∞ with Nf/Nc fixed. We also present expansions for αIR calculated to O (Δf4).

  8. Paired-like homeodomain proteins Phox2a/Arix and Phox2b/NBPhox have similar genetic organization and independently regulate dopamine beta-hydroxylase gene transcription.

    PubMed

    Adachi, M; Browne, D; Lewis, E J

    2000-09-01

    The homeodomain transcription factors Arix/Phox2a and NBPhox/Phox2b play a role in the specification of the noradrenergic phenotype of central and peripheral neurons. To better understand the functions of these two factors, we have compared the genetic organization, chromosomal location, and transcriptional regulatory properties of Arix and NBPhox. The gene structure is very similar, with each gene containing three exons and two introns, extending a total of approximately 5 kb. Arix and NBPhox are unlinked in human and mouse genomes. NBPhox is located on human Chromosome 4p12 and mouse Chromosome 5, while Arix is located on human Chromosome 11q13 and mouse Chromosome 7. Both proteins bind to three sites in the promoter proximal region of the rat dopamine beta-hydroxylase gene (DBH). In vitro, Arix and NBPhox form DNA-independent multimers and exhibit cooperative binding to the DB1 regulatory element, which contains two homeodomain recognition sites. Both proteins regulate transcription from the rat DBH promoter, and transcription is synergistically increased in the presence of the protein kinase A catalytic subunit (PKA) plus either Arix or NBPhox. The transcription factors exhibit similar concentration-dependent efficacies, and when they are coexpressed, transcription is stimulated to a value approximately equal to that seen with either factor alone. The N-terminal segment of Arix is essential for transcriptional regulatory activity, and this region bears 50% identity with NBPhox, suggesting a similar mechanism of transcriptional activation of the DBH gene. We conclude from this study that Arix and NBPhox exhibit indistinguishable and independent transcriptional regulatory properties on the DBH promoter.

  9. Valdecoxib Recovers the Lipid Composition, Order and Dynamics in Colon Cancer Cell Lines Independent of COX-2 Expression: An ATR-FTIR Spectroscopy Study.

    PubMed

    Inan Genç, Aysun; Gok, Seher; Banerjee, Sreeparna; Severcan, Feride

    2017-01-01

    Prostanoids play an important role in a variety of physiological and pathophysiological processes including inflammation and cancer. The rate-limiting step in the prostanoid biosynthesis pathway is catalyzed by cyclooxygenases (COXs). Aberrant expression of the inducible isoform COX-2 plays a significant role in colon cancer initiation and progression. In this study, we have hypothesized that COX-2 specific inhibitors such as Valdecoxib (VLX), being highly hydrophobic, may alter biophysical properties of cellular lipids. In this study, COX-2 expressing (HT29) and COX-2 non-expressing (SW620) colon cancer cell lines were treated with VLX and examined using attenuated total reflection infrared spectroscopy. The results revealed that VLX treatment decreased lipid fluidity in the cells irrespective of COX-2 expression status and affected order parameters of the lipids in both cell lines. Cluster analysis also indicated that the spectral differences between the two cell lines are profound and could be successfully differentiated. Valdecoxib treatment could enhance the composition, order and dynamics of the lipids of colon cancer cells independently of its COX-2 inhibitory mechanism. Valdecoxib has therapeutic effects upon colon cancer, therefore it can be used as an adjuvant and/or chemopreventive agent for colon cancer.

  10. Next-to-leading order QCD predictions for t{gamma} associated production via model-independent flavor-changing neutral-current couplings at hadron colliders

    SciTech Connect

    Zhang Yue; Li Bohua; Li Chongsheng; Gao Jun; Zhu Huaxing

    2011-05-01

    We present the complete next-to-leading order (NLO) QCD predictions for the t{gamma} associated production induced by model-independent tq{gamma} and tqg flavor-changing neutral-current (FCNC) couplings at hadron colliders, respectively. We also consider the mixing effects between the tq{gamma} and tqg FCNC couplings for this process. Our results show that, for the tq{gamma} couplings, the NLO QCD corrections can enhance the total cross sections by about 50% and 40% at the Tevatron and LHC, respectively. Including the contributions from the tq{gamma}, tqg FCNC couplings and their mixing effects, the NLO QCD corrections can enhance the total cross sections by about 50% for the tu{gamma} and tug FCNC couplings, and by about 80% for the tc{gamma} and tcg FCNC couplings at the LHC, respectively. Moreover, the NLO corrections reduce the dependence of the total cross section on the renormalization and factorization scale significantly. We also evaluate the NLO corrections for several important kinematic distributions.

  11. Order Effects of Learning with Modeling and Simulation Software on Field-Dependent and Field-Independent Children's Cognitive Performance: An Interaction Effect

    ERIC Educational Resources Information Center

    Angeli, Charoula; Valanides, Nicos; Polemitou, Eirini; Fraggoulidou, Elena

    2014-01-01

    The study examined the interaction between field dependence-independence (FD/I) and learning with modeling software and simulations, and their effect on children's performance. Participants were randomly assigned into two groups. Group A first learned with a modeling tool and then with simulations. Group B learned first with simulations and then…

  12. Understanding independence

    NASA Astrophysics Data System (ADS)

    Annan, James; Hargreaves, Julia

    2016-04-01

    In order to perform any Bayesian processing of a model ensemble, we need a prior over the ensemble members. In the case of multimodel ensembles such as CMIP, the historical approach of ``model democracy'' (i.e. equal weight for all models in the sample) is no longer credible (if it ever was) due to model duplication and inbreeding. The question of ``model independence'' is central to the question of prior weights. However, although this question has been repeatedly raised, it has not yet been satisfactorily addressed. Here I will discuss the issue of independence and present a theoretical foundation for understanding and analysing the ensemble in this context. I will also present some simple examples showing how these ideas may be applied and developed.

  13. Artifact-Free and Detection-Profile-Independent Higher-Order Fluorescence Correlation Spectroscopy for Microsecond-Resolved Kinetics. 1. Multidetector and Sub-Binning Approach.

    PubMed

    Abdollah-Nia, Farshad; Gelfand, Martin P; Van Orden, Alan

    2017-03-10

    Fluorescence correlation spectroscopy (FCS) is a powerful tool in the time-resolved analysis of nonreacting or reacting molecules in solution, based on fluorescence intensity fluctuations. However, conventional (second-order) FCS alone is insufficient to measure all parameters needed to describe a reaction or mixture, including concentrations, fluorescence brightnesses, and forward and reverse rate constants. For this purpose, correlations of higher powers of fluorescence intensity fluctuations can be calculated to yield additional information from the single-photon data stream collected in an FCS experiment. To describe systems of diffusing and reacting molecules, considering cumulants of fluorescence intensity results in simple expressions in which the reaction and diffusion parts factorize. The computation of higher-order correlations in experiments is hindered by shot-noise and common detector artifacts, the effects of which become worse with increasing order. In this article, we introduce a technique to calculate artifact-free higher-order correlation functions with improved time resolution, and without any need for modeling and calibration of detector artifacts. The technique is formulated for general multidetector experiments and verified in both two-detector and single-detector configurations. Good signal-to-noise ratio is achieved down to 1 μs in correlation curves up to order (2, 2). This capability makes possible a variety of new measurements including multicomponent analysis and fast reaction kinetics, as demonstrated in a companion article (10.1021/acs.jpcb.7b00408).

  14. Choice of Rule-Example Order Used to Teach Mathematics as a Function of Conceptual Level and Field-Dependence-Independence.

    ERIC Educational Resources Information Center

    Gordon, Marshall

    This study determined whether or not there were certain aspects of cognitive/personality style which affected prospective teachers' choice of rule-example order in teaching mathematics. Seventy undergraduate elementary education majors were given the Paragraph Completion Test which measures conceptual level and the Group Embedded Figures Test…

  15. Are Independent Probes Truly Independent?

    ERIC Educational Resources Information Center

    Camp, Gino; Pecher, Diane; Schmidt, Henk G.; Zeelenberg, Rene

    2009-01-01

    The independent cue technique has been developed to test traditional interference theories against inhibition theories of forgetting. In the present study, the authors tested the critical criterion for the independence of independent cues: Studied cues not presented during test (and unrelated to test cues) should not contribute to the retrieval…

  16. Are Independent Probes Truly Independent?

    ERIC Educational Resources Information Center

    Camp, Gino; Pecher, Diane; Schmidt, Henk G.; Zeelenberg, Rene

    2009-01-01

    The independent cue technique has been developed to test traditional interference theories against inhibition theories of forgetting. In the present study, the authors tested the critical criterion for the independence of independent cues: Studied cues not presented during test (and unrelated to test cues) should not contribute to the retrieval…

  17. Creating Multi Objective Value Functions from Non-Independent Values

    DTIC Science & Technology

    2009-03-01

    problems and inconsistencies which make it undesirable for many DMs ( Dyer , 1990), it does help in “…deriving dominance priorities from paired...side note, there exists a similar but stronger independence concept called utility independence. Keeney explains that for a single attribute x1 to be... utility independent of the remaining attributes preference order for lotteries involving only changes in the levels of attributes in x1 does not

  18. Zinc- and iron-dependent cytosolic metallo-β-lactamase domain proteins exhibit similar zinc-binding affinities, independent of an atypical glutamate at the metal-binding site

    PubMed Central

    2004-01-01

    ZiPD (zinc phosphodiesterase; synonyms are ElaC, ecoZ, RNaseZ and 3′ tRNase) and the iron-dependent redox enzyme FlRd (flavorubredoxin) from Escherichia coli represent prototypical cases of proteins sharing the metallo-β-lactamase fold that require strict metal selectivity for catalytic activity, yet their metal selectivity has only been partially understood. In contrast with hydrolytic metallo-β-lactamase proteins, iron-dependent FlRd-like enzymes have an atypical glutamate ligand, which replaces one otherwise conserved histidine ligand. X-ray absorption spectroscopy revealed that the FlRd metallo-β-lactamase domain is capable of incorporating two zinc ions into the binuclear metal-binding site. Zinc dissociation constants, determined by isothermal titration calorimetry are similar for zinc binding to E. coli ZiPD (Kd1=2.2±0.2 μM and Kd2=23.0±0.6 μM) and to the E. coli FlRd metallo-β-lactamase domain (Kd1=0.7±0.1 μM and Kd2=26.0±0.1 μM). In good correspondence, apo-ZiPD requires incubation with 10 μM zinc for full reconstitution of the phosphodiesterase activity. Accordingly, metal selectivity of ZiPD and FlRd only partially relies on first shell metal ligands. Back mutation of the atypical glutamate in FlRd to a histidine unexpectedly resulted in an increased first zinc dissociation constant (Kd1=30±4 μM and Kd2=23±2 μM). In combination with a recent mutational study on ZiPD [Vogel, Schilling and Meyer-Klaucke (2004) Biochemistry 43, 10379–10386], we conclude that the atypical glutamate does not guide metal selectivity of the FlRd metallo-β-lactamase domain but suppresses possible hydrolytic cross-activity. PMID:15324305

  19. Biosimilar Insulins: How Similar is Similar?

    PubMed Central

    Heinemann, Lutz; Hompesch, Marcus

    2011-01-01

    Biosimilar insulins (BIs) are viewed as commercially attractive products by a number of companies. In order to obtain approval in the European Union or the United States, where there is not a single BI currently on the market, a manufacturer needs to demonstrate that a given BI has a safety and efficacy profile that is similar to that of the “original” insulin formulation that is already on the market. As trivial as this may appear at first glance, it is not trivial at all for a good number of reasons that will be discussed in this commentary. As with protein manufacturing, modifications in the structure of the insulin molecule can take place (which can have serious consequences for the biological effects induced), so a rigid and careful assessment is absolutely necessary. The example of Marvel's failed application with the European Medicines Agency provides insights into the regulatory and clinical challenges surrounding the matter of BI. Although a challenging BI approval process might be regarded as a hurdle to keep companies out of certain markets, it is fair to say that the potential safety and efficacy issues surrounding BI are substantial and relevant and do warrant a careful and evidence-driven approval process. PMID:21722590

  20. Salam's independence

    NASA Astrophysics Data System (ADS)

    Fraser, Gordon

    2009-01-01

    In his kind review of my biography of the Nobel laureate Abdus Salam (December 2008 pp45-46), John W Moffat wrongly claims that Salam had "independently thought of the idea of parity violation in weak interactions".

  1. Independent Living.

    ERIC Educational Resources Information Center

    Nathanson, Jeanne H., Ed.

    1994-01-01

    This issue of "OSERS" addresses the subject of independent living of individuals with disabilities. The issue includes a message from Judith E. Heumann, the Assistant Secretary of the Office of Special Education and Rehabilitative Services (OSERS), and 10 papers. Papers have the following titles and authors: "Changes in the…

  2. Independence and Survival.

    ERIC Educational Resources Information Center

    James, H. Thomas

    Independent schools that are of viable size, well managed, and strategically located to meet competition will survive and prosper past the current financial crisis. We live in a complex technological society with insatiable demands for knowledgeable people to keep it running. The future will be marked by the orderly selection of qualified people,…

  3. 'Independence' Panorama

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Click on the image for 'Independence' Panorama (QTVR)

    This is the Spirit 'Independence' panorama, acquired on martian days, or sols, 536 to 543 (July 6 to 13, 2005), from a position in the 'Columbia Hills' near the summit of 'Husband Hill.' The summit of 'Husband Hill' is the peak near the right side of this panorama and is about 100 meters (328 feet) away from the rover and about 30 meters (98 feet) higher in elevation. The rocky outcrops downhill and on the left side of this mosaic include 'Larry's Lookout' and 'Cumberland Ridge,' which Spirit explored in April, May, and June of 2005.

    The panorama spans 360 degrees and consists of 108 individual images, each acquired with five filters of the rover's panoramic camera. The approximate true color of the mosaic was generated using the camera's 750-, 530-, and 480-nanometer filters. During the 8 martian days, or sols, that it took to acquire this image, the lighting varied considerably, partly because of imaging at different times of sol, and partly because of small sol-to-sol variations in the dustiness of the atmosphere. These slight changes produced some image seams and rock shadows. These seams have been eliminated from the sky portion of the mosaic to better simulate the vista a person standing on Mars would see. However, it is often not possible or practical to smooth out such seams for regions of rock, soil, rover tracks or solar panels. Such is the nature of acquiring and assembling large panoramas from the rovers.

  4. Higher-order force gradient symplectic algorithms

    NASA Astrophysics Data System (ADS)

    Chin, Siu A.; Kidwell, Donald W.

    2000-12-01

    We show that a recently discovered fourth order symplectic algorithm, which requires one evaluation of force gradient in addition to three evaluations of the force, when iterated to higher order, yielded algorithms that are far superior to similarly iterated higher order algorithms based on the standard Forest-Ruth algorithm. We gauge the accuracy of each algorithm by comparing the step-size independent error functions associated with energy conservation and the rotation of the Laplace-Runge-Lenz vector when solving a highly eccentric Kepler problem. For orders 6, 8, 10, and 12, the new algorithms are approximately a factor of 103, 104, 104, and 105 better.

  5. Molecular similarity measures.

    PubMed

    Maggiora, Gerald M; Shanmugasundaram, Veerabahu

    2011-01-01

    Molecular similarity is a pervasive concept in chemistry. It is essential to many aspects of chemical reasoning and analysis and is perhaps the fundamental assumption underlying medicinal chemistry. Dissimilarity, the complement of similarity, also plays a major role in a growing number of applications of molecular diversity in combinatorial chemistry, high-throughput screening, and related fields. How molecular information is represented, called the representation problem, is important to the type of molecular similarity analysis (MSA) that can be carried out in any given situation. In this work, four types of mathematical structure are used to represent molecular information: sets, graphs, vectors, and functions. Molecular similarity is a pairwise relationship that induces structure into sets of molecules, giving rise to the concept of chemical space. Although all three concepts - molecular similarity, molecular representation, and chemical space - are treated in this chapter, the emphasis is on molecular similarity measures. Similarity measures, also called similarity coefficients or indices, are functions that map pairs of compatible molecular representations that are of the same mathematical form into real numbers usually, but not always, lying on the unit interval. This chapter presents a somewhat pedagogical discussion of many types of molecular similarity measures, their strengths and limitations, and their relationship to one another. An expanded account of the material on chemical spaces presented in the first edition of this book is also provided. It includes a discussion of the topography of activity landscapes and the role that activity cliffs in these landscapes play in structure-activity studies.

  6. Molecular similarity measures.

    PubMed

    Maggiora, Gerald M; Shanmugasundaram, Veerabahu

    2004-01-01

    Molecular similarity is a pervasive concept in chemistry. It is essential to many aspects of chemical reasoning and analysis and is perhaps the fundamental assumption underlying medicinal chemistry. Dissimilarity, the complement of similarity, also plays a major role in a growing number of applications of molecular diversity in combinatorial chemistry, high-throughput screening, and related fields. How molecular information is represented, called the representation problem, is important to the type of molecular similarity analysis (MSA) that can be carried out in any given situation. In this work, four types of mathematical structure are used to represent molecular information: sets, graphs, vectors, and functions. Molecular similarity is a pairwise relationship that induces structure into sets of molecules, giving rise to the concept of a chemistry space. Although all three concepts molecular similarity, molecular representation, and chemistry space are treated in this chapter, the emphasis is on molecular similarity measures. Similarity measures, also called similarity coefficients or indices, are functions that map pairs of compatible molecular representations, that is, representations of the same mathematical form, into real numbers usually, but not always, lying on the unit interval. This chapter presents a somewhat pedagogical discussion of many types of molecular similarity measures, their strengths and limitations, and their relationship to one another.

  7. Independent Test

    NASA Astrophysics Data System (ADS)

    Nomoto, Hideki; Katahira, Masafumi; Fukatsu, Tsutomu; Okabe, Hideki; Yamanaka, Kohji

    2005-12-01

    This paper describes IV&V (Independent Verification & Validation) methodology applied for the Rendezvous Flight Software (RVFS) of the H-IIA Transfer Vehicle (HTV).HTV is a cargo transportation vehicle to the International Space Station (ISS). RVFS not only controls the HTV's flight sequence autonomously, but also is deployed with two-fault tolerant FDIR (Fault Detection Isolation Recovery) functionality. Since software such as RVFS is very critical for safe and successful HTV operations, exhaustive IV&V is being conducted.RVFS is required to function to avoid HTV's collision to the ISS. The biggest challenge is thoroughness of the verification. Due to its complicated software algorithm to accomplish fully autonomous rendezvous to the ISS, required numbers of test cases can easily go beyond realistic for conventional verification methodologies.IV&V team developed a verification environment on which 1) formal specification model was made from the detailed software design specification and 2) C source code and test sequence were generated/executed from the model automatically.One of the main efforts of this activity was to increase fidelity of the model and the quality of the generated code sufficiently. This will be discussed in the modeling, the model checking and code generation technology sections. The other issue that had to be resolved was the methodology to generate exhaustive test cases for the developed model that takes continuous input values (so called hybrid model). Conventional random test case generation or boundary condition generation does not assure the sufficiency/validity of the test cases because combinations of inputs becomes theoretically infinite for this kind of model [1]. To resolve this problem, IV&V team developed a unique algorithm to generate finite number test cases that satisfies full-scale test requirement. This will be discussed in the testing section.The generated code was put through 550 billion full-path test cases. We succeeded to

  8. The Gender Similarities Hypothesis

    ERIC Educational Resources Information Center

    Hyde, Janet Shibley

    2005-01-01

    The differences model, which argues that males and females are vastly different psychologically, dominates the popular media. Here, the author advances a very different view, the gender similarities hypothesis, which holds that males and females are similar on most, but not all, psychological variables. Results from a review of 46 meta-analyses…

  9. The gender similarities hypothesis.

    PubMed

    Hyde, Janet Shibley

    2005-09-01

    The differences model, which argues that males and females are vastly different psychologically, dominates the popular media. Here, the author advances a very different view, the gender similarities hypothesis, which holds that males and females are similar on most, but not all, psychological variables. Results from a review of 46 meta-analyses support the gender similarities hypothesis. Gender differences can vary substantially in magnitude at different ages and depend on the context in which measurement occurs. Overinflated claims of gender differences carry substantial costs in areas such as the workplace and relationships.

  10. Where Similarity Beats Redundancy: The Importance of Context, Higher Order Similarity, and Response Assignment

    ERIC Educational Resources Information Center

    Eidels, Ami; Townsend, James T.; Pomerantz, James R.

    2008-01-01

    People are especially efficient in processing certain visual stimuli such as human faces or good configurations. It has been suggested that topology and geometry play important roles in configural perception. Visual search is one area in which configurality seems to matter. When either of 2 target features leads to a correct response and the…

  11. Gender similarities and differences.

    PubMed

    Hyde, Janet Shibley

    2014-01-01

    Whether men and women are fundamentally different or similar has been debated for more than a century. This review summarizes major theories designed to explain gender differences: evolutionary theories, cognitive social learning theory, sociocultural theory, and expectancy-value theory. The gender similarities hypothesis raises the possibility of theorizing gender similarities. Statistical methods for the analysis of gender differences and similarities are reviewed, including effect sizes, meta-analysis, taxometric analysis, and equivalence testing. Then, relying mainly on evidence from meta-analyses, gender differences are reviewed in cognitive performance (e.g., math performance), personality and social behaviors (e.g., temperament, emotions, aggression, and leadership), and psychological well-being. The evidence on gender differences in variance is summarized. The final sections explore applications of intersectionality and directions for future research.

  12. Additive Similarity Trees

    ERIC Educational Resources Information Center

    Sattath, Shmuel; Tversky, Amos

    1977-01-01

    Tree representations of similarity data are investigated. Hierarchical clustering is critically examined, and a more general procedure, called the additive tree, is presented. The additive tree representation is then compared to multidimensional scaling. (Author/JKS)

  13. 7 CFR 1217.61 - Independent evaluation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOFTWOOD LUMBER RESEARCH, PROMOTION, CONSUMER EDUCATION AND INDUSTRY INFORMATION ORDER Softwood Lumber Research, Promotion, Consumer Education, and Industry Information Order Promotion, Research, and Information § 1217.61 Independent...

  14. The Qualitative Similarity Hypothesis

    ERIC Educational Resources Information Center

    Paul, Peter V.; Lee, Chongmin

    2010-01-01

    Evidence is presented for the qualitative similarity hypothesis (QSH) with respect to children and adolescents who are d/Deaf or hard of hearing. The primary focus is on the development of English language and literacy skills, and some information is provided on the acquisition of English as a second language. The QSH is briefly discussed within…

  15. Domain similarity based orthology detection.

    PubMed

    Bitard-Feildel, Tristan; Kemena, Carsten; Greenwood, Jenny M; Bornberg-Bauer, Erich

    2015-05-13

    Orthologous protein detection software mostly uses pairwise comparisons of amino-acid sequences to assert whether two proteins are orthologous or not. Accordingly, when the number of sequences for comparison increases, the number of comparisons to compute grows in a quadratic order. A current challenge of bioinformatic research, especially when taking into account the increasing number of sequenced organisms available, is to make this ever-growing number of comparisons computationally feasible in a reasonable amount of time. We propose to speed up the detection of orthologous proteins by using strings of domains to characterize the proteins. We present two new protein similarity measures, a cosine and a maximal weight matching score based on domain content similarity, and new software, named porthoDom. The qualities of the cosine and the maximal weight matching similarity measures are compared against curated datasets. The measures show that domain content similarities are able to correctly group proteins into their families. Accordingly, the cosine similarity measure is used inside porthoDom, the wrapper developed for proteinortho. porthoDom makes use of domain content similarity measures to group proteins together before searching for orthologs. By using domains instead of amino acid sequences, the reduction of the search space decreases the computational complexity of an all-against-all sequence comparison. We demonstrate that representing and comparing proteins as strings of discrete domains, i.e. as a concatenation of their unique identifiers, allows a drastic simplification of search space. porthoDom has the advantage of speeding up orthology detection while maintaining a degree of accuracy similar to proteinortho. The implementation of porthoDom is released using python and C++ languages and is available under the GNU GPL licence 3 at http://www.bornberglab.org/pages/porthoda .

  16. Numerical orbit integration efficiency of the Delaunay-Similar elements

    NASA Technical Reports Server (NTRS)

    Pierce, S.

    1974-01-01

    Orbit equations with a set of conservative and a set of nonconservative perturbing potentials were considered. Scheifele's DS formulation of these equations has dependent variables similar to Delaunay's orbital elements with the true anomaly as the independent variable. Efficiency curves of computing cost v.s. accuracy were constructed for Adams integrators of order of 2 through 15 with several correcting algorithms and for a Runga-Kutta integrator. Considering stability regions, choices were made for the optimally efficient integration modes for the DS elements. Integrating in these modes reduces computing costs for a specified accuracy.

  17. Comparison of hydrological similarity measures

    NASA Astrophysics Data System (ADS)

    Rianna, Maura; Ridolfi, Elena; Manciola, Piergiorgio; Napolitano, Francesco; Russo, Fabio

    2016-04-01

    The use of a traditional at site approach for the statistical characterization and simulation of spatio-temporal precipitation fields has a major recognized drawback. Indeed, the weakness of the methodology is related to the estimation of rare events and it involves the uncertainty of the at-site sample statistical inference, because of the limited length of records. In order to overcome the lack of at-site observations, regional frequency approach uses the idea of substituting space for time to estimate design floods. The conventional regional frequency analysis estimates quantile values at a specific site from multi-site analysis. The main idea is that homogeneous sites, once pooled together, have similar probability distribution curves of extremes, except for a scaling factor. The method for pooling groups of sites can be based on geographical or climatological considerations. In this work the region of influence (ROI) pooling method is compared with an entropy-based one. The ROI is a flexible pooling group approach which defines for each site its own "region" formed by a unique set of similar stations. The similarity is found through the Euclidean distance metric in the attribute space. Here an alternative approach based on entropy is introduced to cluster homogeneous sites. The core idea is that homogeneous sites share a redundant (i.e. similar) amount of information. Homogeneous sites are pooled through a hierarchical selection based on the mutual information index (i.e. a measure of redundancy). The method is tested on precipitation data in Central Italy area.

  18. Similar enzymes, different structures

    PubMed Central

    Tarasev, Michael; Kaddis, Catherine S.; Yin, Sheng; Loo, Joseph A.; Burgner, John; Ballou, David P.

    2007-01-01

    Phthalate dioxygenase (PDO) is a member of a class of bacterial oxygenases that contain both Rieske [2Fe-2S] and Fe(II) mononuclear centers. Recent crystal structures of several Rieske dioxygenases showed that they exist as α3β3 multimers with subunits arranged head-to-tail in α and β stacked planar consists of only α-subunits, remains to be solved. Although similar to other Rieske dioxygenases in many aspects, PDO was shown to differ in the mechanism of catalysis. Gel filtration and analytical centrifugation experiments, supplemented with mass spectrometric analysis (both ESI-MS and ESI-GEMMA), in this work showed a hexameric arrangement of subunits in the PDO multimer. Our proposed model for the subunit arrangement in PDO postulates two α3 planar rings one on top the other, similar to the α3β3 arrangement in other Rieske dioxygenases. Unlike other Rieske dioxygenases, this arrangement brings two Rieske and two mononuclear centers, all on separate subunits, into proximity, allowing their cooperation for catalysis. Potential reasons necessitating this unusual structural arrangement are discussed. PMID:17764654

  19. Assumed policy similarity and voter preference.

    PubMed

    Quist, Ryan M; Crano, William D

    2003-04-01

    The effects of attitude similarity on voters' preferences were examined. Using secondary analyses, the authors created measures of assumed similarity across 6 issues between voters and U.S. presidential candidates (in 1972). Greater similarity was associated with greater attraction (operationalized in terms of voters' presidential preferences). In 2 independent analyses, perceived similarity resulted in predictive accuracy of 84% to 88%. In a 3rd analysis, the predictive efficiency of each of 6 similarity measures was determined and used to develop a model that accurately predicted voters' actions in a hold-out sample. Findings demonstrate the importance of perceived attitude similarity in determining voter preferences and suggest the utility of earlier similarity-attraction research for the development of models of policy choice behavior.

  20. Variable Order and Distributed Order Fractional Operators

    NASA Technical Reports Server (NTRS)

    Lorenzo, Carl F.; Hartley, Tom T.

    2002-01-01

    Many physical processes appear to exhibit fractional order behavior that may vary with time or space. The continuum of order in the fractional calculus allows the order of the fractional operator to be considered as a variable. This paper develops the concept of variable and distributed order fractional operators. Definitions based on the Riemann-Liouville definitions are introduced and behavior of the operators is studied. Several time domain definitions that assign different arguments to the order q in the Riemann-Liouville definition are introduced. For each of these definitions various characteristics are determined. These include: time invariance of the operator, operator initialization, physical realization, linearity, operational transforms. and memory characteristics of the defining kernels. A measure (m2) for memory retentiveness of the order history is introduced. A generalized linear argument for the order q allows the concept of "tailored" variable order fractional operators whose a, memory may be chosen for a particular application. Memory retentiveness (m2) and order dynamic behavior are investigated and applications are shown. The concept of distributed order operators where the order of the time based operator depends on an additional independent (spatial) variable is also forwarded. Several definitions and their Laplace transforms are developed, analysis methods with these operators are demonstrated, and examples shown. Finally operators of multivariable and distributed order are defined in their various applications are outlined.

  1. The qualitative similarity hypothesis.

    PubMed

    Paul, Peter V; Lee, Chongmin

    2010-01-01

    Evidence is presented for the qualitative similarity hypothesis (QSH) with respect to children and adolescents who are d/Deaf or hard of hearing. The primary focus is on the development of English language and literacy skills, and some information is provided on the acquisition of English as a second language. The QSH is briefly discussed within the purview of two groups of cognitive models: those that emphasize the cognitive development of individuals and those that pertain to disciplinary or knowledge structures. It is argued that the QSH has scientific merit with implications for classroom instruction. Future research should examine the validity of the QSH in other disciplines such as mathematics and science and should include perspectives from social as well as cognitive models.

  2. Retrieving similar color images

    NASA Astrophysics Data System (ADS)

    Gagliardi, Isabella; Schettini, Raimondo

    1998-09-01

    There is a great demand for efficient tools that can, on the basis of the pictorial content, organize large quantities of images and rapidly retrieve those of interest. With that goal in mind we present a method for indexing complex color images. The basic idea is to exploit image data decomposition and compression based on the standard Haar multiresolution wavelet transform to describe image content. In this way we are able to effectively eliminate data redundancy and concisely represent the salient features of the image in image signatures of predefined lengths. In the retrieval phase image signatures are compared using a similarity measure that the system has 'learned' from user's. Experimental results confirm the feasibility of our approach, which outperforms more standard procedures, in retrieval accuracy and at lower computational costs.

  3. Similarity transformed semiclassical dynamics

    NASA Astrophysics Data System (ADS)

    Van Voorhis, Troy; Heller, Eric J.

    2003-12-01

    In this article, we employ a recently discovered criterion for selecting important contributions to the semiclassical coherent state propagator [T. Van Voorhis and E. J. Heller, Phys. Rev. A 66, 050501 (2002)] to study the dynamics of many dimensional problems. We show that the dynamics are governed by a similarity transformed version of the standard classical Hamiltonian. In this light, our selection criterion amounts to using trajectories generated with the untransformed Hamiltonian as approximate initial conditions for the transformed boundary value problem. We apply the new selection scheme to some multidimensional Henon-Heiles problems and compare our results to those obtained with the more sophisticated Herman-Kluk approach. We find that the present technique gives near-quantitative agreement with the the standard results, but that the amount of computational effort is less than Herman-Kluk requires even when sophisticated integral smoothing techniques are employed in the latter.

  4. What causes similarity in catchments?

    NASA Astrophysics Data System (ADS)

    Savenije, Hubert

    2014-05-01

    One of the biggest issues in hydrology is how to handle the heterogeneity of catchment properties at different scales. But is this really such a big issue? Is this problem not merely the consequence of how we conceptualise and how we model catchments? Is there not far more similarity than we observe. Maybe we are not looking at the right things or at the right scale to see the similarity. The identity of catchments is largely determined by: the landscape, the ecosystem living on the landscape, and the geology, in that order. Soils, which are often seen as a crucial aspect of hydrological behaviour, are far less important, as will be demonstrated. The main determinants of hydrological behaviour are: the landscape composition, the rooting depth and the phenology. These determinants are a consequence of landscape and ecosystem evolution, which, in turn, are the manifestations of entropy production. There are striking similarities between catchments. The different runoff processes from hillslopes are linked and similar in different environments (McDonnell, 2013). Wetlands behave similarly all over the world. The key is to classify landscapes and to link the ecosystems living on them to climate. The ecosystem then is the main controller of hydrological behaviour. Besides phenology, the rooting depth is key in determining runoff behaviour. Both are strongly linked to climate and much less to soil properties. An example is given of how rooting depth is determined by climate, and how rooting depth can be predicted without calibration, providing a strong constraints on the prediction of rainfall partitioning and catchment runoff.

  5. Distorting limb design for dynamically similar locomotion.

    PubMed Central

    Bullimore, Sharon R.; Burn, Jeremy F.

    2004-01-01

    Terrestrial mammals of different sizes tend to move in a dynamically similar manner when travelling at speeds corresponding to equal values of the Froude number. This means that certain dimensionless locomotor parameters, including peak vertical ground reaction force relative to body weight, stride length relative to leg length and duty factor, are independent of animal size. The Froude number is consequently used to define equivalent speeds for mammals of different sizes. However, most musculoskeletal-tissue properties, including tendon elastic modulus, do not scale in a dynamically similar manner. Therefore, mammals could not be completely dynamically similar, even if perfectly geometrically similar. We argue that, for mammals to move in a dynamically similar manner, they must exhibit systematic 'distortions' of limb structure with size that compensate for the size independence of the tendon elastic modulus. An implication of this is that comparing mammals at equal Froude numbers cannot remove all size-dependent effects. We show that the previously published allometry of limb moment arms is sufficient to compensate for size-independent tendon properties. This suggests that it is an important factor in allowing mammals of different sizes to move in a dynamically similar manner. PMID:15058440

  6. Self-similar breakup of near-inviscid liquids

    NASA Astrophysics Data System (ADS)

    Castrejon-Pita, Alfonso A.; Castrejon-Pita, J. Rafael; Lister, John R.; Hinch, E. John; Hutchings, Ian M.

    2012-11-01

    Experimental results are presented for the final stages of drop pinch-off and ligament breakup for different initial conditions. Water and ethanol were used as working fluids. High-speed imaging and image analysis were utilized in order to determine the contraction rate of the thinning neck and the shape of the liquid thread just before the breakup. Our results show that the geometry of the breakup of near-inviscid fluids is self-similar in the domain of simple dripping. We also demonstrate that, independently of the initial conditions, the necking of these liquids scales with τ 2 / 3, asymptotically giving a unique breakup angle of 18 . 0 +/- 0 .4° . Both observations are in complete agreement with previous theoretical predictions. The angle converges towards self similarity like τ 1 / 2, also as predicted. Project supported by the EPSRC-UK (EP/G029458/1 and EP/H018913/1) and Cambridge-KACST.

  7. GS-align for glycan structure alignment and similarity measurement

    PubMed Central

    Lee, Hui Sun; Jo, Sunhwan; Mukherjee, Srayanta; Park, Sang-Jun; Skolnick, Jeffrey; Lee, Jooyoung; Im, Wonpil

    2015-01-01

    Motivation: Glycans play critical roles in many biological processes, and their structural diversity is key for specific protein-glycan recognition. Comparative structural studies of biological molecules provide useful insight into their biological relationships. However, most computational tools are designed for protein structure, and despite their importance, there is no currently available tool for comparing glycan structures in a sequence order- and size-independent manner. Results: A novel method, GS-align, is developed for glycan structure alignment and similarity measurement. GS-align generates possible alignments between two glycan structures through iterative maximum clique search and fragment superposition. The optimal alignment is then determined by the maximum structural similarity score, GS-score, which is size-independent. Benchmark tests against the Protein Data Bank (PDB) N-linked glycan library and PDB homologous/non-homologous N-glycoprotein sets indicate that GS-align is a robust computational tool to align glycan structures and quantify their structural similarity. GS-align is also applied to template-based glycan structure prediction and monosaccharide substitution matrix generation to illustrate its utility. Availability and implementation: http://www.glycanstructure.org/gsalign. Contact: wonpil@ku.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25857669

  8. Generalized structure of higher order nonclassicality

    NASA Astrophysics Data System (ADS)

    Verma, Amit; Pathak, Anirban

    2010-02-01

    A generalized notion of higher order nonclassicality (in terms of higher order moments) is introduced. Under this generalized framework of higher order nonclassicality, conditions of higher order squeezing and higher order subpoissonian photon statistics are derived. A simpler form of the Hong-Mandel higher order squeezing criterion is derived under this framework by using an operator ordering theorem introduced by us in [A. Pathak, J. Phys. A 33 (2000) 5607]. It is also generalized for multi-photon Bose operators of Brandt and Greenberg. Similarly, condition for higher order subpoissonian photon statistics is derived by normal ordering of higher powers of number operator. Further, with the help of simple density matrices, it is shown that the higher order antibunching (HOA) and higher order subpoissonian photon statistics (HOSPS) are not the manifestation of the same phenomenon and consequently it is incorrect to use the condition of HOA as a test of HOSPS. It is also shown that the HOA and HOSPS may exist even in absence of the corresponding lower order phenomenon. Binomial state, nonlinear first order excited squeezed state (NLESS) and nonlinear vacuum squeezed state (NLVSS) are used as examples of quantum state and it is shown that these states may show higher order nonclassical characteristics. It is observed that the Binomial state which is always antibunched, is not always higher order squeezed and NLVSS which shows higher order squeezing does not show HOSPS and HOA. The opposite is observed in NLESS and consequently it is established that the HOSPS and HOS are two independent signatures of higher order nonclassicality.

  9. Order Theoretical Semantic Recommendation

    SciTech Connect

    Joslyn, Cliff A.; Hogan, Emilie A.; Paulson, Patrick R.; Peterson, Elena S.; Stephan, Eric G.; Thomas, Dennis G.

    2013-07-23

    Mathematical concepts of order and ordering relations play multiple roles in semantic technologies. Discrete totally ordered data characterize both input streams and top-k rank-ordered recommendations and query output, while temporal attributes establish numerical total orders, either over time points or in the more complex case of startend temporal intervals. But also of note are the fully partially ordered data, including both lattices and non-lattices, which actually dominate the semantic strcuture of ontological systems. Scalar semantic similarities over partially-ordered semantic data are traditionally used to return rank-ordered recommendations, but these require complementation with true metrics available over partially ordered sets. In this paper we report on our work in the foundations of partial order measurement in ontologies, with application to top-k semantic recommendation in workflows.

  10. Independent Peer Reviews

    SciTech Connect

    2012-03-16

    Independent Assessments: DOE's Systems Integrator convenes independent technical reviews to gauge progress toward meeting specific technical targets and to provide technical information necessary for key decisions.

  11. 7 CFR 1214.61 - Independent evaluation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., RESEARCH, AND INFORMATION ORDER Christmas Tree Promotion, Research, and Information Order Promotion, Research and Information § 1214.61 Independent evaluation. The Board shall, not less often than once every five years, authorize and fund, from funds otherwise available to the Board, an independent evaluation...

  12. Order Up

    ERIC Educational Resources Information Center

    Gibeault, Michael

    2005-01-01

    Change orders. The words can turn the stomachs of administrators. Horror stories about change orders create fear and distrust among school officials, designers and builders. Can change orders be avoided? If car manufacturers can produce millions of intricately designed vehicles, why can't the same quality control be achieved on a construction…

  13. Order Up

    ERIC Educational Resources Information Center

    Gibeault, Michael

    2005-01-01

    Change orders. The words can turn the stomachs of administrators. Horror stories about change orders create fear and distrust among school officials, designers and builders. Can change orders be avoided? If car manufacturers can produce millions of intricately designed vehicles, why can't the same quality control be achieved on a construction…

  14. Order Nidovirales

    USDA-ARS?s Scientific Manuscript database

    This chapter, entitled "Order Nidovirales", is for inclusion in the Ninth Report of the International Committee on Taxonomy of Viruses (ICTV), to be published as both a single volume text and online. The chapter details the taxonomy of members of the Nidovirus order, including family Arteriviridae o...

  15. Culture independent PCR: an alternative enzyme discovery strategy.

    PubMed

    Jacobsen, Jonas; Lydolph, Magnus; Lange, Lene

    2005-01-01

    Degenerate primers were designed for use in a culture-independent PCR screening of DNA from composite fungal communities, inhabiting residues of corn stovers and leaves. According to similarity searches and alignments amplified clone sequences affiliated with glycosyl hydrolase family 7 and glycosyl hydrolase family 45 though significant sequence divergence was observed. Glycosyl hydrolases from families 7 and 45 play a crucial role in biomass conversion to fuel ethanol. Research in this renewable energy source has two objectives: (i) To contribute to development of a renewable alternative to world's limited crude fossil oil reserves and (ii) to reduce air pollution. Amplification with 18S rDNA-specific primers revealed species within the ascomycetous orders Sordariales and Hypocreales as well as basidiomycetous order Agaricales to be present in these communities. Our study documents the value of culture-independent PCR in microbial diversity studies and could add to development of a new enzyme screening technology.

  16. Self-similarity in nature

    NASA Astrophysics Data System (ADS)

    Timashev, S. F.

    2000-02-01

    A general phenomenological approach to the analysis of experimental temporal, spatial and energetic series for extracting truly physical non-model parameters ("passport data") is presented, which may be used to characterize and distinguish the evolution as well as the spatial and energetic structure of any open nonlinear dissipative system. This methodology is based on a postulate concerning the crucial information contained in the sequences of non-regularities of the measured dynamic variable (temporal, spatial, energetic). In accordance with this approach, multi-parametric formulas for dynamic variable power spectra as well as for structural functions of different orders are identical for every spatial-temporal-energetic level of the system under consideration. In effect, this entails the introduction of a new kind of self-similarity in Nature. An algorithm has been developed for obtaining as many "passport data" as are necessary for the characterization of a dynamic system. Applications of this approach in the analysis of various experimental series (temporal, spatial, energetic) demonstrate its potential for defining adequate phenomenological parameters of different dynamic processes and structures.

  17. Independent Study in Iowa.

    ERIC Educational Resources Information Center

    Idaho Univ., Moscow.

    This guide to independent study in Idaho begins with introductory information on the following aspects of independent study: the Independent Study in Idaho consortium, student eligibility, special needs, starting dates, registration, costs, textbooks and instructional materials, e-mail and faxing, refunds, choosing a course, time limits, speed…

  18. Criteria for dynamic similarity in bouncing gaits.

    PubMed

    Bullimore, Sharon R; Donelan, J Maxwell

    2008-01-21

    Animals of different sizes tend to move in a dynamically similar manner when travelling at speeds corresponding to equal values of a dimensionless parameter (DP) called the Froude number. Consequently, the Froude number has been widely used for defining equivalent speeds and predicting speeds of locomotion by extinct species and on other planets. However, experiments using simulated reduced gravity have demonstrated that equality of the Froude number does not guarantee dynamic similarity. This has cast doubt upon the usefulness of the Froude number in locomotion research. Here we use dimensional analysis of the planar spring-mass model, combined with Buckingham's Pi-Theorem, to demonstrate that four DPs must be equal for dynamic similarity in bouncing gaits such as trotting, hopping and bipedal running. This can be reduced to three DPs by applying the constraint of maintaining a constant average speed of locomotion. Sensitivity analysis indicates that all of these DPs are important for predicting dynamic similarity. We show that the reason humans do not run in a dynamically similar manner at equal Froude number in different levels of simulated reduced gravity is that dimensionless leg stiffness decreases as gravity increases. The reason that the Froude number can predict dynamic similarity in Earth gravity is that dimensionless leg stiffness and dimensionless vertical landing speed are both independent of size. In conclusion, although equal Froude number is not sufficient for dynamic similarity, it is a necessary condition. Therefore, to detect fundamental differences in locomotion, animals of different sizes should be compared at equal Froude number, so that they can be as close to dynamic similarity as possible. More generally, the concept of dynamic similarity provides a powerful framework within which similarities and differences in locomotion can be interpreted.

  19. Nuclear markers reveal that inter-lake cichlids' similar morphologies do not reflect similar genealogy.

    PubMed

    Kassam, Daud; Seki, Shingo; Horic, Michio; Yamaoka, Kosaku

    2006-08-01

    The apparent inter-lake morphological similarity among East African Great Lakes' cichlid species/genera has left evolutionary biologists asking whether such similarity is due to sharing of common ancestor or mere convergent evolution. In order to answer such question, we first used Geometric Morphometrics, GM, to quantify morphological similarity and then subsequently used Amplified Fragment Length Polymorphism, AFLP, to determine if similar morphologies imply shared ancestry or convergent evolution. GM revealed that not all presumed morphological similar pairs were indeed similar, and the dendrogram generated from AFLP data indicated distinct clusters corresponding to each lake and not inter-lake morphological similar pairs. Such results imply that the morphological similarity is due to convergent evolution and not shared ancestry. The congruency of GM and AFLP generated dendrograms imply that GM is capable of picking up phylogenetic signal, and thus GM can be potential tool in phylogenetic systematics.

  20. Functional Similarity and Interpersonal Attraction.

    ERIC Educational Resources Information Center

    Neimeyer, Greg J.; Neimeyer, Robert A.

    1981-01-01

    Students participated in dyadic disclosure exercises over a five-week period. Results indicated members of high functional similarity dyads evidenced greater attraction to one another than did members of low functional similarity dyads. "Friendship" pairs of male undergraduates displayed greater functional similarity than did…

  1. An Approach to Keeping Independent Colleges Independent.

    ERIC Educational Resources Information Center

    Northwest Area Foundation, St. Paul, Minn.

    As a result of the financial difficulties faced by independent colleges in the northwestern United States, the Northwest Area Foundation in 1972 surveyed the administrations of 80 private colleges to get a profile of the colleges, a list of their current problems, and some indication of how the problems might be approached. The three top problems…

  2. Native Nations of Quebec: Independence within Independence?

    ERIC Educational Resources Information Center

    Williams, Paul

    1995-01-01

    Aboriginal nations oppose the separation of Quebec from Canada because they favor confederations, multiple international boundaries present jurisdictional nightmares, federal programs might disappear, and Quebec's history of aggression against Aboriginal peoples plus the ethnic nature of its nationalism suggest an independent Quebec is a potential…

  3. The Case of the Similar Trees.

    ERIC Educational Resources Information Center

    Meyer, Rochelle Wilson

    1982-01-01

    A possible logical flaw based on similar triangles is discussed with the Sherlock Holmes mystery, "The Muskgrave Ritual." The possible flaw has to do with the need for two trees to have equal growth rates over a 250-year period in order for the solution presented to work. (MP)

  4. The Case of the Similar Trees.

    ERIC Educational Resources Information Center

    Meyer, Rochelle Wilson

    1982-01-01

    A possible logical flaw based on similar triangles is discussed with the Sherlock Holmes mystery, "The Muskgrave Ritual." The possible flaw has to do with the need for two trees to have equal growth rates over a 250-year period in order for the solution presented to work. (MP)

  5. Homology-independent metrics for comparative genomics.

    PubMed

    Coutinho, Tarcisio José Domingos; Franco, Glória Regina; Lobo, Francisco Pereira

    2015-01-01

    A mainstream procedure to analyze the wealth of genomic data available nowadays is the detection of homologous regions shared across genomes, followed by the extraction of biological information from the patterns of conservation and variation observed in such regions. Although of pivotal importance, comparative genomic procedures that rely on homology inference are obviously not applicable if no homologous regions are detectable. This fact excludes a considerable portion of "genomic dark matter" with no significant similarity - and, consequently, no inferred homology to any other known sequence - from several downstream comparative genomic methods. In this review we compile several sequence metrics that do not rely on homology inference and can be used to compare nucleotide sequences and extract biologically meaningful information from them. These metrics comprise several compositional parameters calculated from sequence data alone, such as GC content, dinucleotide odds ratio, and several codon bias metrics. They also share other interesting properties, such as pervasiveness (patterns persist on smaller scales) and phylogenetic signal. We also cite examples where these homology-independent metrics have been successfully applied to support several bioinformatics challenges, such as taxonomic classification of biological sequences without homology inference. They where also used to detect higher-order patterns of interactions in biological systems, ranging from detecting coevolutionary trends between the genomes of viruses and their hosts to characterization of gene pools of entire microbial communities. We argue that, if correctly understood and applied, homology-independent metrics can add important layers of biological information in comparative genomic studies without prior homology inference.

  6. Feature matching algorithm based on spatial similarity

    NASA Astrophysics Data System (ADS)

    Tang, Wenjing; Hao, Yanling; Zhao, Yuxin; Li, Ning

    2008-10-01

    The disparities of features that represent the same real world entities from disparate sources usually occur, thus the identification or matching of features is crutial to the map conflation. Motivated by the idea of identifying the same entities through integrating known information by eyes, the feature matching algorithm based on spatial similarity is proposed in this paper. Total similarity is obtained by integrating positional similarity, shape similarity and size similarity with a weighted average algorithm, then the matching entities is achieved according to the maximum total similarity. The matching of areal features is analyzed in detail. Regarding the areal feature as a whole, the proposed algorithm identifies the same areal features by their shape-center points in order to calculate their positional similarity, and shape similarity is given by the function of describing the shape, which ensures its precision not be affected by interferes and avoids the loss of shape information, furthermore the size of areal features is measured by their covered areas. Test results show the stability and reliability of the proposed algorithm, and its precision and recall are higher than other matching algorithm.

  7. Characterizing limit order prices

    NASA Astrophysics Data System (ADS)

    Withanawasam, R. M.; Whigham, P. A.; Crack, Timothy Falcon

    2013-11-01

    A computational model of a limit order book is used to study the effect of different limit order distribution offsets. Reference prices such as same side/contra side best market prices and last traded price are considered in combination with different price offset distributions. We show that when characterizing limit order prices, varying the offset distribution only produces different behavior when the reference price is the contra side best price. Irrespective of the underlying mechanisms used in computing the limit order prices, the shape of the price graph and the behavior of the average order book profile distribution are strikingly similar in all the considered reference prices/offset distributions. This implies that existing averaging methods can cancel variabilities in limit order book shape/attributes and may be misleading.

  8. a Comparison of Semantic Similarity Models in Evaluating Concept Similarity

    NASA Astrophysics Data System (ADS)

    Xu, Q. X.; Shi, W. Z.

    2012-08-01

    The semantic similarities are important in concept definition, recognition, categorization, interpretation, and integration. Many semantic similarity models have been established to evaluate semantic similarities of objects or/and concepts. To find out the suitability and performance of different models in evaluating concept similarities, we make a comparison of four main types of models in this paper: the geometric model, the feature model, the network model, and the transformational model. Fundamental principles and main characteristics of these models are introduced and compared firstly. Land use and land cover concepts of NLCD92 are employed as examples in the case study. The results demonstrate that correlations between these models are very high for a possible reason that all these models are designed to simulate the similarity judgement of human mind.

  9. Hiring and Retaining Great Independent School Teachers

    ERIC Educational Resources Information Center

    Balossi, Matt; Hernández, Natalie R.

    2016-01-01

    While numerous studies measure teacher effectiveness in public schools, there is little research on teacher quality among independent schools. In fact, the topic of teacher quality in public schools receives widespread media coverage, funding, and special interest. In order to better understand how independent schools describe high-quality…

  10. Learning similarity with multikernel method.

    PubMed

    Tang, Yi; Li, Luoqing; Li, Xuelong

    2011-02-01

    In the field of machine learning, it is a key issue to learn and represent similarity. This paper focuses on the problem of learning similarity with a multikernel method. Motivated by geometric intuition and computability, similarity between patterns is proposed to be measured by their included angle in a kernel-induced Hilbert space. Having noticed that the cosine of such an included angle can be represented by a normalized kernel, it can be said that the task of learning similarity is equivalent to learning an appropriate normalized kernel. In addition, an error bound is also established for learning similarity with the multikernel method. Based on this bound, a boosting-style algorithm is developed. The preliminary experiments validate the effectiveness of the algorithm for learning similarity.

  11. Similarity Learning of Manifold Data.

    PubMed

    Chen, Si-Bao; Ding, Chris H Q; Luo, Bin

    2015-09-01

    Without constructing adjacency graph for neighborhood, we propose a method to learn similarity among sample points of manifold in Laplacian embedding (LE) based on adding constraints of linear reconstruction and least absolute shrinkage and selection operator type minimization. Two algorithms and corresponding analyses are presented to learn similarity for mix-signed and nonnegative data respectively. The similarity learning method is further extended to kernel spaces. The experiments on both synthetic and real world benchmark data sets demonstrate that the proposed LE with new similarity has better visualization and achieves higher accuracy in classification.

  12. Similarities between catalase and cytosolic epoxide hydrolase.

    PubMed

    Guenthner, T M; Qato, M; Whalen, R; Glomb, S

    1989-01-01

    Cytosolic epoxide hydrolase, measured as trans-stilbene oxide hydrolase activity, was isolated and purified from human and guinea pig liver cytosol. Antiserum to the guinea pig liver preparation reacted strongly with bovine liver catalase. We determined that this lack of selectivity of the antiserum was due to catalase contamination of the epoxide hydrolase preparation. We also determined that several commercial catalase preparations are contaminated with cytosolic epoxide hydrolase. Our human epoxide hydrolase preparation contained no detectable catalase contamination, yet antiserum to this protein also cross-reacted slightly with catalase, indicating some intrinsic similarity between the two enzymes. We conclude that catalase and cytosolic epoxide hydrolase contain some similar immunogenic epitopes, and we surmise that similarities between the subunits of these two enzymes may lead to their partial copurification. Functional similarities between the two enzymes are also demonstrated, as several compounds that inhibit catalase are also shown to inhibit cytosolic epoxide hydrolase activity in the same concentration range and rank order.

  13. Self-similarity in Laplacian growth

    SciTech Connect

    Mineev-weinstein, Mark; Zabrodin, Anton; Abanov, Artem

    2008-01-01

    We consider Laplacian Growth of self-similar domains in different geometries. Self-similarity determines the analytic structure of the Schwarz function of the moving boundary. The knowledge of this analytic structure allows us to derive the integral equation for the conformal map. It is shown that solutions to the integral equation obey also a second-order differential equation which is the 1D Schroedinger equation with the sinh{sup -2}-potential. The solutions, which are expressed through the Gauss hypergeometric function, characterize the geometry of self-similar patterns in a wedge. We also find the potential for the Coulomb gas representation of the self-similar Laplacian growth in a wedge and calculate the corresponding free energy.

  14. Horton Law in Self-Similar Trees

    NASA Astrophysics Data System (ADS)

    Kovchegov, Yevgeniy; Zaliapin, Ilya

    2016-04-01

    Self-similarity of random trees is related to the operation of pruning. Pruning ℛ cuts the leaves and their parental edges and removes the resulting chains of degree-two nodes from a finite tree. A Horton-Strahler order of a vertex v and its parental edge is defined as the minimal number of prunings necessary to eliminate the subtree rooted at v. A branch is a group of neighboring vertices and edges of the same order. The Horton numbers 𝒩k[K] and 𝒩ij[K] are defined as the expected number of branches of order k, and the expected number of order-i branches that merged order-j branches, j > i, respectively, in a finite tree of order K. The Tokunaga coefficients are defined as Tij[K] = 𝒩ij[K]/𝒩j[K]. The pruning decreases the orders of tree vertices by unity. A rooted full binary tree is said to be mean-self-similar if its Tokunaga coefficients are invariant with respect to pruning: Tk := Ti,i+k[K]. We show that for self-similar trees, the condition limsupk→∞Tk1/k < ∞ is necessary and sufficient for the existence of the strong Horton law: 𝒩k[K]/𝒩1[K] → R1-k, as K →∞ for some R > 0 and every k ≥ 1. This work is a step toward providing rigorous foundations for the Horton law that, being omnipresent in natural branching systems, has escaped so far a formal explanation.

  15. Discuss Similarity Using Visual Intuition

    ERIC Educational Resources Information Center

    Cox, Dana C.; Lo, Jane-Jane

    2012-01-01

    The change in size from a smaller shape to a larger similar shape (or vice versa) is created through continuous proportional stretching or shrinking in every direction. Students cannot solve similarity tasks simply by iterating or partitioning a composed unit, strategies typically used on numerical proportional tasks. The transition to thinking…

  16. Dynamic similarity in erosional processes

    USGS Publications Warehouse

    Scheidegger, A.E.

    1963-01-01

    A study is made of the dynamic similarity conditions obtaining in a variety of erosional processes. The pertinent equations for each type of process are written in dimensionless form; the similarity conditions can then easily be deduced. The processes treated are: raindrop action, slope evolution and river erosion. ?? 1963 Istituto Geofisico Italiano.

  17. Discuss Similarity Using Visual Intuition

    ERIC Educational Resources Information Center

    Cox, Dana C.; Lo, Jane-Jane

    2012-01-01

    The change in size from a smaller shape to a larger similar shape (or vice versa) is created through continuous proportional stretching or shrinking in every direction. Students cannot solve similarity tasks simply by iterating or partitioning a composed unit, strategies typically used on numerical proportional tasks. The transition to thinking…

  18. Counterbalancing for Serial Order Carryover Effects in Experimental Condition Orders

    ERIC Educational Resources Information Center

    Brooks, Joseph L.

    2012-01-01

    Reactions of neural, psychological, and social systems are rarely, if ever, independent of previous inputs and states. The potential for serial order carryover effects from one condition to the next in a sequence of experimental trials makes counterbalancing of condition order an essential part of experimental design. Here, a method is proposed…

  19. Counterbalancing for Serial Order Carryover Effects in Experimental Condition Orders

    ERIC Educational Resources Information Center

    Brooks, Joseph L.

    2012-01-01

    Reactions of neural, psychological, and social systems are rarely, if ever, independent of previous inputs and states. The potential for serial order carryover effects from one condition to the next in a sequence of experimental trials makes counterbalancing of condition order an essential part of experimental design. Here, a method is proposed…

  20. American Independence. Fifth Grade.

    ERIC Educational Resources Information Center

    Crosby, Annette

    This fifth grade teaching unit covers early conflicts between the American colonies and Britain, battles of the American Revolutionary War, and the Declaration of Independence. Knowledge goals address the pre-revolutionary acts enforced by the British, the concepts of conflict and independence, and the major events and significant people from the…

  1. Independence of Internal Auditors.

    ERIC Educational Resources Information Center

    Montondon, Lucille; Meixner, Wilda F.

    1993-01-01

    A survey of 288 college and university auditors investigated patterns in their appointment, reporting, and supervisory practices as indicators of independence and objectivity. Results indicate a weakness in the positioning of internal auditing within institutions, possibly compromising auditor independence. Because the auditing function is…

  2. Fostering Musical Independence

    ERIC Educational Resources Information Center

    Shieh, Eric; Allsup, Randall Everett

    2016-01-01

    Musical independence has always been an essential aim of musical instruction. But this objective can refer to everything from high levels of musical expertise to more student choice in the classroom. While most conceptualizations of musical independence emphasize the demonstration of knowledge and skills within particular music traditions, this…

  3. American Independence. Fifth Grade.

    ERIC Educational Resources Information Center

    Crosby, Annette

    This fifth grade teaching unit covers early conflicts between the American colonies and Britain, battles of the American Revolutionary War, and the Declaration of Independence. Knowledge goals address the pre-revolutionary acts enforced by the British, the concepts of conflict and independence, and the major events and significant people from the…

  4. Higher Order Crossings.

    DTIC Science & Technology

    1987-05-01

    L AD-A199 489 HIGHER ORDER CROSSIMGSCU) MRRYLANDUUNIV COLLEGE PARK B KEDEN RAY 87 AFOSR-TR-87-1768 AFOSR-82-ai87 UNCLASSIFIED FVG 12/2 ML 6oi 132. @4...20332-6448 611027 2304 A5 MIt.rA TILsk~bbibl cankusd"i Higher Order Crossings M2 PAOWNAL AUTHORS1) B. Kedem all, TYP6 OF REPORT 1 136, TIME COVERED Lj...device that is useful as a diagnostic tool for higher order crossings was introduced. The graphical tool is also useful as a descriptive similarity

  5. Towards Personalized Medicine: Leveraging Patient Similarity and Drug Similarity Analytics

    PubMed Central

    Zhang, Ping; Wang, Fei; Hu, Jianying; Sorrentino, Robert

    2014-01-01

    The rapid adoption of electronic health records (EHR) provides a comprehensive source for exploratory and predictive analytic to support clinical decision-making. In this paper, we investigate how to utilize EHR to tailor treatments to individual patients based on their likelihood to respond to a therapy. We construct a heterogeneous graph which includes two domains (patients and drugs) and encodes three relationships (patient similarity, drug similarity, and patient-drug prior associations). We describe a novel approach for performing a label propagation procedure to spread the label information representing the effectiveness of different drugs for different patients over this heterogeneous graph. The proposed method has been applied on a real-world EHR dataset to help identify personalized treatments for hypercholesterolemia. The experimental results demonstrate the effectiveness of the approach and suggest that the combination of appropriate patient similarity and drug similarity analytics could lead to actionable insights for personalized medicine. Particularly, by leveraging drug similarity in combination with patient similarity, our method could perform well even on new or rarely used drugs for which there are few records of known past performance. PMID:25717413

  6. Towards personalized medicine: leveraging patient similarity and drug similarity analytics.

    PubMed

    Zhang, Ping; Wang, Fei; Hu, Jianying; Sorrentino, Robert

    2014-01-01

    The rapid adoption of electronic health records (EHR) provides a comprehensive source for exploratory and predictive analytic to support clinical decision-making. In this paper, we investigate how to utilize EHR to tailor treatments to individual patients based on their likelihood to respond to a therapy. We construct a heterogeneous graph which includes two domains (patients and drugs) and encodes three relationships (patient similarity, drug similarity, and patient-drug prior associations). We describe a novel approach for performing a label propagation procedure to spread the label information representing the effectiveness of different drugs for different patients over this heterogeneous graph. The proposed method has been applied on a real-world EHR dataset to help identify personalized treatments for hypercholesterolemia. The experimental results demonstrate the effectiveness of the approach and suggest that the combination of appropriate patient similarity and drug similarity analytics could lead to actionable insights for personalized medicine. Particularly, by leveraging drug similarity in combination with patient similarity, our method could perform well even on new or rarely used drugs for which there are few records of known past performance.

  7. Statistical assessment of dissolution and drug release profile similarity using a model-dependent approach.

    PubMed

    Berry, Mark R; Likar, Michael D

    2007-10-18

    A general multivariate procedure for assessing the similarity of dissolution and drug release profiles was developed. A mathematical model is fit to the data, and Hotelling's T(2) test is used to calculate the joint confidence region around the vector of differences between least-squares estimates of the parameters in the model. The method of Lagrange multipliers is used to determine if this confidence region is enclosed within a predetermined similarity region, and profile similarity is claimed if this is the case. The first-order, Gompertz, logistic, second-order, and Weibull models were fit to the in vitro extended-release profile of pseudoephedrine HCl from an asymmetric membrane (AM) film-coated osmotic tablet. The first-order model was selected because of its simplicity and because it was the best-fitting model according to a modified form of Akaike's Information Criterion. A nonlinear response surface model was also developed so that the formulator could calculate how much of the AM film coat should be applied in order to obtain the desired drug release profile. The usefulness of this model-dependent procedure was further demonstrated during an analytical method transfer exercise, where it was used to compare the drug release profiles obtained by two independent laboratories; additional research is required, however, before the appropriate acceptance criteria for demonstrating profile similarity can be recommended.

  8. Renewing the respect for similarity.

    PubMed

    Edelman, Shimon; Shahbazi, Reza

    2012-01-01

    In psychology, the concept of similarity has traditionally evoked a mixture of respect, stemming from its ubiquity and intuitive appeal, and concern, due to its dependence on the framing of the problem at hand and on its context. We argue for a renewed focus on similarity as an explanatory concept, by surveying established results and new developments in the theory and methods of similarity-preserving associative lookup and dimensionality reduction-critical components of many cognitive functions, as well as of intelligent data management in computer vision. We focus in particular on the growing family of algorithms that support associative memory by performing hashing that respects local similarity, and on the uses of similarity in representing structured objects and scenes. Insofar as these similarity-based ideas and methods are useful in cognitive modeling and in AI applications, they should be included in the core conceptual toolkit of computational neuroscience. In support of this stance, the present paper (1) offers a discussion of conceptual, mathematical, computational, and empirical aspects of similarity, as applied to the problems of visual object and scene representation, recognition, and interpretation, (2) mentions some key computational problems arising in attempts to put similarity to use, along with their possible solutions, (3) briefly states a previously developed similarity-based framework for visual object representation, the Chorus of Prototypes, along with the empirical support it enjoys, (4) presents new mathematical insights into the effectiveness of this framework, derived from its relationship to locality-sensitive hashing (LSH) and to concomitant statistics, (5) introduces a new model, the Chorus of Relational Descriptors (ChoRD), that extends this framework to scene representation and interpretation, (6) describes its implementation and testing, and finally (7) suggests possible directions in which the present research program can be

  9. Renewing the respect for similarity

    PubMed Central

    Edelman, Shimon; Shahbazi, Reza

    2012-01-01

    In psychology, the concept of similarity has traditionally evoked a mixture of respect, stemming from its ubiquity and intuitive appeal, and concern, due to its dependence on the framing of the problem at hand and on its context. We argue for a renewed focus on similarity as an explanatory concept, by surveying established results and new developments in the theory and methods of similarity-preserving associative lookup and dimensionality reduction—critical components of many cognitive functions, as well as of intelligent data management in computer vision. We focus in particular on the growing family of algorithms that support associative memory by performing hashing that respects local similarity, and on the uses of similarity in representing structured objects and scenes. Insofar as these similarity-based ideas and methods are useful in cognitive modeling and in AI applications, they should be included in the core conceptual toolkit of computational neuroscience. In support of this stance, the present paper (1) offers a discussion of conceptual, mathematical, computational, and empirical aspects of similarity, as applied to the problems of visual object and scene representation, recognition, and interpretation, (2) mentions some key computational problems arising in attempts to put similarity to use, along with their possible solutions, (3) briefly states a previously developed similarity-based framework for visual object representation, the Chorus of Prototypes, along with the empirical support it enjoys, (4) presents new mathematical insights into the effectiveness of this framework, derived from its relationship to locality-sensitive hashing (LSH) and to concomitant statistics, (5) introduces a new model, the Chorus of Relational Descriptors (ChoRD), that extends this framework to scene representation and interpretation, (6) describes its implementation and testing, and finally (7) suggests possible directions in which the present research program can be

  10. Self-similar aftershock rates

    NASA Astrophysics Data System (ADS)

    Davidsen, Jörn; Baiesi, Marco

    2016-08-01

    In many important systems exhibiting crackling noise—an intermittent avalanchelike relaxation response with power-law and, thus, self-similar distributed event sizes—the "laws" for the rate of activity after large events are not consistent with the overall self-similar behavior expected on theoretical grounds. This is particularly true for the case of seismicity, and a satisfying solution to this paradox has remained outstanding. Here, we propose a generalized description of the aftershock rates which is both self-similar and consistent with all other known self-similar features. Comparing our theoretical predictions with high-resolution earthquake data from Southern California we find excellent agreement, providing particularly clear evidence for a unified description of aftershocks and foreshocks. This may offer an improved framework for time-dependent seismic hazard assessment and earthquake forecasting.

  11. Self-similar aftershock rates.

    PubMed

    Davidsen, Jörn; Baiesi, Marco

    2016-08-01

    In many important systems exhibiting crackling noise-an intermittent avalanchelike relaxation response with power-law and, thus, self-similar distributed event sizes-the "laws" for the rate of activity after large events are not consistent with the overall self-similar behavior expected on theoretical grounds. This is particularly true for the case of seismicity, and a satisfying solution to this paradox has remained outstanding. Here, we propose a generalized description of the aftershock rates which is both self-similar and consistent with all other known self-similar features. Comparing our theoretical predictions with high-resolution earthquake data from Southern California we find excellent agreement, providing particularly clear evidence for a unified description of aftershocks and foreshocks. This may offer an improved framework for time-dependent seismic hazard assessment and earthquake forecasting.

  12. Similarity of the Velocity Profile

    DTIC Science & Technology

    2014-10-01

    su x (with 0 constantb = ) is the empirically derived velocity scale developed by Zagarola and Smits [5] for turbulent boundary layer flow...Zagarola and Smits and others have shown that the velocity scaling factor given by Eq. 5 with sδ as the boundary layer thickness can collapse certain...and Smits , it is important to point out that the fact that the similarity length scale factor and the similarity velocity scale factor must follow

  13. [Accreditation of Independent Ethics Committees].

    PubMed

    Ramiro Avilés, Miguel A

    According to Law 14/2007 and Royal Decree 1090/2015, biomedical research must be assessed by an Research Ethics Committee (REC), which must be accredited as an Research ethics committee for clinical trials involving medicinal products (RECm) if the opinion is issued for a clinical trial involving medicinal products or clinical research with medical devices. The aim of this study is to ascertain how IEC and IECm accreditation is regulated. National and regional legislation governing biomedical research was analysed. No clearly-defined IEC or IECm accreditation procedures exist in the national or regional legislation. Independent Ethics Committees are vital for the development of basic or clinical biomedical research, and they must be accredited by an external body in order to safeguard their independence, multidisciplinary composition and review procedures. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Does morphological convergence imply functional similarity? A test using the evolution of quadrupedalism in ornithischian dinosaurs.

    PubMed

    Maidment, Susannah C R; Barrett, Paul M

    2012-09-22

    Convergent morphologies are thought to indicate functional similarity, arising because of a limited number of evolutionary or developmental pathways. Extant taxa displaying convergent morphologies are used as analogues to assess function in extinct taxa with similar characteristics. However, functional studies of extant taxa have shown that functional similarity can arise from differing morphologies, calling into question the paradigm that form and function are closely related. We test the hypothesis that convergent skeletal morphology indicates functional similarity in the fossil record using ornithischian dinosaurs. The rare transition from bipedality to quadrupedality occurred at least three times independently in this clade, resulting in a suite of convergent osteological characteristics. We use homology rather than analogy to provide an independent line of evidence about function, reconstructing soft tissues using the extant phylogenetic bracket and applying biomechanical concepts to produce qualitative assessments of muscle leverage. We also optimize character changes to investigate the sequence of character acquisition. Different lineages of quadrupedal ornithischian dinosaur stood and walked differently from each other, falsifying the hypothesis that osteological convergence indicates functional similarity. The acquisition of features correlated with quadrupedalism generally occurs in the same order in each clade, suggesting underlying developmental mechanisms that act as evolutionary constraints.

  15. Does morphological convergence imply functional similarity? A test using the evolution of quadrupedalism in ornithischian dinosaurs

    PubMed Central

    Maidment, Susannah C. R.; Barrett, Paul M.

    2012-01-01

    Convergent morphologies are thought to indicate functional similarity, arising because of a limited number of evolutionary or developmental pathways. Extant taxa displaying convergent morphologies are used as analogues to assess function in extinct taxa with similar characteristics. However, functional studies of extant taxa have shown that functional similarity can arise from differing morphologies, calling into question the paradigm that form and function are closely related. We test the hypothesis that convergent skeletal morphology indicates functional similarity in the fossil record using ornithischian dinosaurs. The rare transition from bipedality to quadrupedality occurred at least three times independently in this clade, resulting in a suite of convergent osteological characteristics. We use homology rather than analogy to provide an independent line of evidence about function, reconstructing soft tissues using the extant phylogenetic bracket and applying biomechanical concepts to produce qualitative assessments of muscle leverage. We also optimize character changes to investigate the sequence of character acquisition. Different lineages of quadrupedal ornithischian dinosaur stood and walked differently from each other, falsifying the hypothesis that osteological convergence indicates functional similarity. The acquisition of features correlated with quadrupedalism generally occurs in the same order in each clade, suggesting underlying developmental mechanisms that act as evolutionary constraints. PMID:22719033

  16. Developing Independence in Decoding.

    ERIC Educational Resources Information Center

    Spiegel, Dixie Lee

    1985-01-01

    Proposes three guidelines to assist teachers in helping students become independent decoders: (1) teach the flexible use of a repertoire of strategies, (2) don't overnurture, and (3) provide a strong vocabulary development program. (FL)

  17. Media independent interface

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The work done on the Media Independent Interface (MII) Interface Control Document (ICD) program is described and recommendations based on it were made. Explanations and rationale for the content of the ICD itself are presented.

  18. Dreaming and waking: similarities and differences revisited.

    PubMed

    Kahan, Tracey L; LaBerge, Stephen P

    2011-09-01

    Dreaming is often characterized as lacking high-order cognitive (HOC) skills. In two studies, we test the alternative hypothesis that the dreaming mind is highly similar to the waking mind. Multiple experience samples were obtained from late-night REM sleep and waking, following a systematic protocol described in Kahan (2001). Results indicated that reported dreaming and waking experiences are surprisingly similar in their cognitive and sensory qualities. Concurrently, ratings of dreaming and waking experiences were markedly different on questions of general reality orientation and logical organization (e.g., the bizarreness or typicality of the events, actions, and locations). Consistent with other recent studies (e.g., Bulkeley & Kahan, 2008; Kozmová & Wolman, 2006), experiences sampled from dreaming and waking were more similar with respect to their process features than with respect to their structural features. Copyright © 2010 Elsevier Inc. All rights reserved.

  19. Similarity Metrics for Closed Loop Dynamic Systems

    NASA Technical Reports Server (NTRS)

    Whorton, Mark S.; Yang, Lee C.; Bedrossian, Naz; Hall, Robert A.

    2008-01-01

    To what extent and in what ways can two closed-loop dynamic systems be said to be "similar?" This question arises in a wide range of dynamic systems modeling and control system design applications. For example, bounds on error models are fundamental to the controller optimization with modern control design methods. Metrics such as the structured singular value are direct measures of the degree to which properties such as stability or performance are maintained in the presence of specified uncertainties or variations in the plant model. Similarly, controls-related areas such as system identification, model reduction, and experimental model validation employ measures of similarity between multiple realizations of a dynamic system. Each area has its tools and approaches, with each tool more or less suited for one application or the other. Similarity in the context of closed-loop model validation via flight test is subtly different from error measures in the typical controls oriented application. Whereas similarity in a robust control context relates to plant variation and the attendant affect on stability and performance, in this context similarity metrics are sought that assess the relevance of a dynamic system test for the purpose of validating the stability and performance of a "similar" dynamic system. Similarity in the context of system identification is much more relevant than are robust control analogies in that errors between one dynamic system (the test article) and another (the nominal "design" model) are sought for the purpose of bounding the validity of a model for control design and analysis. Yet system identification typically involves open-loop plant models which are independent of the control system (with the exception of limited developments in closed-loop system identification which is nonetheless focused on obtaining open-loop plant models from closed-loop data). Moreover the objectives of system identification are not the same as a flight test and

  20. Interspecies gene function prediction using semantic similarity.

    PubMed

    Yu, Guoxian; Luo, Wei; Fu, Guangyuan; Wang, Jun

    2016-12-23

    Gene Ontology (GO) is a collaborative project that maintains and develops controlled vocabulary (or terms) to describe the molecular function, biological roles and cellular location of gene products in a hierarchical ontology. GO also provides GO annotations that associate genes with GO terms. GO consortium independently and collaboratively annotate terms to gene products, mainly from model organisms (or species) they are interested in. Due to experiment ethics, research interests of biologists and resources limitations, homologous genes from different species currently are annotated with different terms. These differences can be more attributed to incomplete annotations of genes than to functional difference between them. Semantic similarity between genes is derived from GO hierarchy and annotations of genes. It is positively correlated with the similarity derived from various types of biological data and has been applied to predict gene function. In this paper, we investigate whether it is possible to replenish annotations of incompletely annotated genes by using semantic similarity between genes from two species with homology. For this investigation, we utilize three representative semantic similarity metrics to compute similarity between genes from two species. Next, we determine the k nearest neighborhood genes from the two species based on the chosen metric and then use terms annotated to k neighbors of a gene to replenish annotations of that gene. We perform experiments on archived (from Jan-2014 to Jan-2016) GO annotations of four species (Human, Mouse, Danio rerio and Arabidopsis thaliana) to assess the contribution of semantic similarity between genes from different species. The experimental results demonstrate that: (1) semantic similarity between genes from homologous species contributes much more on the improved accuracy (by 53.22%) than genes from single species alone, and genes from two species with low homology; (2) GO annotations of genes from

  1. Sibling similarity in family formation.

    PubMed

    Raab, Marcel; Fasang, Anette Eva; Karhula, Aleksi; Erola, Jani

    2014-12-01

    Sibling studies have been widely used to analyze the impact of family background on socioeconomic and, to a lesser extent, demographic outcomes. We contribute to this literature with a novel research design that combines sibling comparisons and sequence analysis to analyze longitudinal family-formation trajectories of siblings and unrelated persons. This allows us to scrutinize in a more rigorous way whether sibling similarity exists in family-formation trajectories and whether siblings' shared background characteristics, such as parental education and early childhood family structure, can account for similarity in family formation. We use Finnish register data from 1987 through 2007 to construct longitudinal family-formation trajectories in young adulthood for siblings and unrelated dyads (N = 14,257 dyads). Findings show that family formation is moderately but significantly more similar for siblings than for unrelated dyads, also after controlling for crucial parental background characteristics. Shared parental background characteristics add surprisingly little to account for sibling similarity in family formation. Instead, gender and the respondents' own education are more decisive forces in the stratification of family formation. Yet, family internal dynamics seem to reinforce this stratification such that siblings have a higher probability to experience similar family-formation patterns. In particular, patterns that correspond with economic disadvantage are concentrated within families. This is in line with a growing body of research highlighting the importance of family structure in the reproduction of social inequality.

  2. Similarity, invariance, and musical variation.

    PubMed

    McAdams, S; Matzkin, D

    2001-06-01

    Perceptual similarity underlies a number of important psychological properties of musical materials, including perceptual invariance under transformation, categorization, recognition, and the sense of familiarity. Mental processes involved in the perception of musical similarity may be an integral part of the functional logic of music composition and thus underly important aspects of musical experience. How much and in what ways can musical materials be varied and still be considered as perceptually related or as belonging to the same category? The notions of musical material, musical variation, perceptual similarity and invariance, and form-bearing dimensions are considered in this light. Recent work on similarity perception has demonstrated that the transformation space for a given musical material is limited by several factors ranging from degree of match of the values of auditory attributes of the events composing the sequences to their relations of various levels of abstraction and to the degree that the transformation respects the grammar of the musical system within which the material was composed. These notions and results are considered in the light of future directions of research, particularly concerning the role of similarity and invariance in the understanding of musical form during listening.

  3. What difference reveals about similarity.

    PubMed

    Sagi, Eyal; Gentner, Dedre; Lovett, Andrew

    2012-08-01

    Detecting that two images are different is faster for highly dissimilar images than for highly similar images. Paradoxically, we showed that the reverse occurs when people are asked to describe how two images differ--that is, to state a difference between two images. Following structure-mapping theory, we propose that this disassociation arises from the multistage nature of the comparison process. Detecting that two images are different can be done in the initial (local-matching) stage, but only for pairs with low overlap; thus, "different" responses are faster for low-similarity than for high-similarity pairs. In contrast, identifying a specific difference generally requires a full structural alignment of the two images, and this alignment process is faster for high-similarity pairs. We described four experiments that demonstrate this dissociation and show that the results can be simulated using the Structure-Mapping Engine. These results pose a significant challenge for nonstructural accounts of similarity comparison and suggest that structural alignment processes play a significant role in visual comparison.

  4. Visualizing multiple word similarity measures.

    PubMed

    Kievit-Kylar, Brent; Jones, Michael N

    2012-09-01

    Although many recent advances have taken place in corpus-based tools, the techniques used to guide exploration and evaluation of these systems have advanced little. Typically, the plausibility of a semantic space is explored by sampling the nearest neighbors to a target word and evaluating the neighborhood on the basis of the modeler's intuition. Tools for visualization of these large-scale similarity spaces are nearly nonexistent. We present a new open-source tool to plot and visualize semantic spaces, thereby allowing researchers to rapidly explore patterns in visual data that describe the statistical relations between words. Words are visualized as nodes, and word similarities are shown as directed edges of varying strengths. The "Word-2-Word" visualization environment allows for easy manipulation of graph data to test word similarity measures on their own or in comparisons between multiple similarity metrics. The system contains a large library of statistical relationship models, along with an interface to teach them from various language sources. The modularity of the visualization environment allows for quick insertion of new similarity measures so as to compare new corpus-based metrics against the current state of the art. The software is available at www.indiana.edu/~semantic/word2word/.

  5. Quantifying Similarity in Seismic Polarizations

    NASA Astrophysics Data System (ADS)

    Eaton, D. W. S.; Jones, J. P.; Caffagni, E.

    2015-12-01

    Measuring similarity in seismic attributes can help identify tremor, low S/N signals, and converted or reflected phases, in addition to diagnosing site noise and sensor misalignment in arrays. Polarization analysis is a widely accepted method for studying the orientation and directional characteristics of seismic phases via. computed attributes, but similarity is ordinarily discussed using qualitative comparisons with reference values. Here we introduce a technique for quantitative polarization similarity that uses weighted histograms computed in short, overlapping time windows, drawing on methods adapted from the image processing and computer vision literature. Our method accounts for ambiguity in azimuth and incidence angle and variations in signal-to-noise (S/N) ratio. Using records of the Mw=8.3 Sea of Okhotsk earthquake from CNSN broadband sensors in British Columbia and Yukon Territory, Canada, and vertical borehole array data from a monitoring experiment at Hoadley gas field, central Alberta, Canada, we demonstrate that our method is robust to station spacing. Discrete wavelet analysis extends polarization similarity to the time-frequency domain in a straightforward way. Because histogram distance metrics are bounded by [0 1], clustering allows empirical time-frequency separation of seismic phase arrivals on single-station three-component records. Array processing for automatic seismic phase classification may be possible using subspace clustering of polarization similarity, but efficient algorithms are required to reduce the dimensionality.

  6. Similarity law for rf breakdown

    NASA Astrophysics Data System (ADS)

    Lisovskiy, V.; Booth, J.-P.; Landry, K.; Douai, D.; Cassagne, V.; Yegorenkov, V.

    2008-04-01

    This paper demonstrates that the similarity law for the rf gas breakdown has the form Urf=ψ(p·L,L/R,f·L)(where Urf is the rf breakdown voltage, p is the gas pressure, L and R are the length and diameter of the discharge tube, respectively, f is the frequency of the rf electric field). It means that two rf breakdown curves registered for narrow inter-electrode gaps or in geometrically similar tubes and depicted in the Urf(p·L) graph will coincide only when the condition f·L=const is met. This similarity law follows from the rf gas breakdown equation and it is well supported by the results of measurements.

  7. Steps, stages, and structure: finding compensatory order in scientific theories.

    PubMed

    Rutjens, Bastiaan T; van Harreveld, Frenk; van der Pligt, Joop; Kreemers, Loes M; Noordewier, Marret K

    2013-05-01

    Stage theories are prominent and controversial in science. One possible reason for their appeal is that they provide order and predictability. Participants in Experiment 1 rated stage theories as more orderly and predictable (but less credible) than continuum theories. In Experiments 2-5, we showed that order threats increase the appeal of stage theories of grief (Experiment 2) and moral development (Experiments 4 and 5). Experiment 3 yielded similar results for a stage theory on Alzheimer's disease characterized by predictable decline, suggesting that preference for stage theories is independent of valence. Experiment 4 showed that the effect of threat on theory preference was mediated by the motivated perception of order, and Experiment 5 revealed that it is particularly the fixed order of stages that increases their appeal. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  8. Do rats learn conditional independence?

    PubMed Central

    Timberlake, William

    2017-01-01

    If acquired associations are to accurately represent real relevance relations, there is motivation for the hypothesis that learning will, in some circumstances, be more appropriately modelled, not as direct dependence, but as conditional independence. In a serial compound conditioning experiment, two groups of rats were presented with a conditioned stimulus (CS1) that imperfectly (50%) predicted food, and was itself imperfectly predicted by a CS2. Groups differed in the proportion of CS2 presentations that were ultimately followed by food (25% versus 75%). Thus, the information presented regarding the relevance of CS2 to food was ambiguous between direct dependence and conditional independence (given CS1). If rats learnt that food was conditionally independent of CS2, given CS1, subjects of both groups should thereafter respond similarly to CS2 alone. Contrary to the conditionality hypothesis, subjects attended to the direct food predictability of CS2, suggesting that rats treat even distal stimuli in a CS sequence as immediately relevant to food, not conditional on an intermediate stimulus. These results urge caution in representing indirect associations as conditional associations, accentuate the theoretical weight of the Markov condition in graphical models, and challenge theories to articulate the conditions under which animals are expected to learn conditional associations, if ever. PMID:28386451

  9. Dimensional analysis and theory of biological similarity.

    PubMed

    Günther, B

    1975-10-01

    From this review we conclude the following: 1) The body weight of an organism is an adequate reference index for the correlation of morphological and physiological characteristics. In comparative physiology, body weight can be recommended as a unifying frame of reference, particularly if the ponderal scale includes several decades, in order to apply logarithmic scales for the variables involved. (See article). 2) The statistical analysis of the experimental data can be represented conveniently by means of the logarithmic equivalent of Huxley's allometric equation (y = a-Wb), which is the most simple and at the same time the most versatile mathematical expression for intra- or interspecies comparisons. The exponents (b) for the allometric equations can be predicted for all biological variables definable in terms of the MLT system of physics (M = mass, L = length, T = time) or of a four-dimensional system MLTt where t = temperature. 3) By means of dimensional analysis and the theory of biological similarity a range of similarity criteria can be established: a) mechanical or dynamic similarity, b) kinematic or biological similarity; and c) hydrodynamic or transport similarity. Most functions obey the so-called biological (kinematic) similarity, particularly when the concept of operational time is introduced into Lambert-Teissier's original theory. 4) A satisfactory correlation (r = 0.99) for 80 empirical allometric exponents (b) describing morphological and physiological characteristics of living beings was found. These results are discussed in relation to Rosen's optimality principles in biology. 5) Organisms should be considered as mixed regimes. This means that no single similarity criterion can predict the allometric exponent (b) of all functions that dimensionally belong to MLT or MLTt systems, despite the fact that in the great majority of cases kinematic similarity will satisfactorily predict the reduced exponent (b). Nevertheless, in some instances mechanical

  10. Phylogenetic metrics of community similarity.

    PubMed

    Ives, Anthony R; Helmus, Matthew R

    2010-11-01

    We derive a new metric of community similarity that takes into account the phylogenetic relatedness among species. This metric, phylogenetic community dissimilarity (PCD), can be partitioned into two components, a nonphylogenetic component that reflects shared species between communities (analogous to Sørensen' s similarity metric) and a phylogenetic component that reflects the evolutionary relationships among nonshared species. Therefore, even if a species is not shared between two communities, it will increase the similarity of the two communities if it is phylogenetically related to species in the other community. We illustrate PCD with data on fish and aquatic macrophyte communities from 59 temperate lakes. Dissimilarity between fish communities associated with environmental differences between lakes often has a phylogenetic component, whereas this is not the case for macrophyte communities. With simulations, we then compare PCD with two other metrics of phylogenetic community similarity, II(ST) and UniFrac. Of the three metrics, PCD was best at identifying environmental drivers of community dissimilarity, showing lower variability and greater statistical power. Thus, PCD is a statistically powerful metric that separates the effects of environmental drivers on compositional versus phylogenetic components of community structure.

  11. Learning Summarization by Using Similarities.

    ERIC Educational Resources Information Center

    Capus, Laurence; Tourigny, Nicole

    1998-01-01

    Discusses a research project aimed at designing a computer-based system to help students learn to summarize French texts by using a method called Case-Based Reasoning (CBR). Such a system uses previous, similar situations to make a new summary by reusing and adapting the same summarization rules. The rationale underlying the learning of text…

  12. What Difference Reveals about Similarity

    ERIC Educational Resources Information Center

    Sagi, Eyal; Gentner, Dedre; Lovett, Andrew

    2012-01-01

    Detecting that two images are different is faster for highly dissimilar images than for highly similar images. Paradoxically, we showed that the reverse occurs when people are asked to describe "how" two images differ--that is, to state a difference between two images. Following structure-mapping theory, we propose that this…

  13. Packing density of rigid aggregates is independent of scale

    PubMed Central

    Zangmeister, Christopher D.; Radney, James G.; Dockery, Lance T.; Young, Jessica T.; Ma, Xiaofei; You, Rian; Zachariah, Michael R.

    2014-01-01

    Large planetary seedlings, comets, microscale pharmaceuticals, and nanoscale soot particles are made from rigid, aggregated subunits that are compacted under low compression into larger structures spanning over 10 orders of magnitude in dimensional space. Here, we demonstrate that the packing density (θf) of compacted rigid aggregates is independent of spatial scale for systems under weak compaction. The θf of rigid aggregated structures across six orders of magnitude were measured using nanoscale spherical soot aerosol composed of aggregates with ∼17-nm monomeric subunits and aggregates made from uniform monomeric 6-mm spherical subunits at the macroscale. We find θf = 0.36 ± 0.02 at both dimensions. These values are remarkably similar to θf observed for comet nuclei and measured values of other rigid aggregated systems across a wide variety of spatial and formative conditions. We present a packing model that incorporates the aggregate morphology and show that θf is independent of both monomer and aggregate size. These observations suggest that the θf of rigid aggregates subject to weak compaction forces is independent of spatial dimension across varied formative conditions. PMID:24927577

  14. Independent technical review, handbook

    SciTech Connect

    Not Available

    1994-02-01

    Purpose Provide an independent engineering review of the major projects being funded by the Department of Energy, Office of Environmental Restoration and Waste Management. The independent engineering review will address questions of whether the engineering practice is sufficiently developed to a point where a major project can be executed without significant technical problems. The independent review will focus on questions related to: (1) Adequacy of development of the technical base of understanding; (2) Status of development and availability of technology among the various alternatives; (3) Status and availability of the industrial infrastructure to support project design, equipment fabrication, facility construction, and process and program/project operation; (4) Adequacy of the design effort to provide a sound foundation to support execution of project; (5) Ability of the organization to fully integrate the system, and direct, manage, and control the execution of a complex major project.

  15. Temporal similarity measures for querying clinical workflows.

    PubMed

    Combi, Carlo; Gozzi, Matteo; Oliboni, Barbara; Juarez, Jose M; Marin, Roque

    2009-05-01

    In this paper, we extend a preliminary proposal and discuss in a deeper and more formal way an approach to evaluate temporal similarity between clinical workflow cases (i.e., executions of clinical processes). More precisely, we focus on (i) the representation of clinical processes by using a temporal conceptual workflow model; (ii) the definition of ad hoc temporal constraint networks to formally represent clinical workflow cases; (iii) the definition of temporal similarity for clinical workflow cases based on the comparison of temporal constraint networks; (iv) the management of the similarity of clinical processes related to the Italian guideline for stroke prevention and management (SPREAD). Clinical processes are composed by clinical activities to be done by given actors in a given order satisfying given temporal constraints. This description means that clinical processes can be seen as organizational processes, and modeled by workflow schemata. When a workflow schema represents a clinical process, its cases represent different instances derived from dealing with different patients in different situations. With respect to all the cases related to a workflow schema, each clinical case can be different with respect to its structure and to its temporal aspects. Clinical cases can be stored in clinical databases and information retrieval can be done evaluating the similarity between workflow cases. We first describe a possible approach to the conceptual modeling of a clinical process, by using a temporally extended workflow model. Then, we define how a workflow case can be represented as a set of activities, and show how to express them through temporal constraint networks. Once we have built temporal constraint networks related to the cases to compare, we propose a similarity function able to evaluate the differences between the considered cases with respect to the order and duration of corresponding activities, and with respect to the presence/absence of some

  16. Latent semantic analysis cosines as a cognitive similarity measure: Evidence from priming studies.

    PubMed

    Günther, Fritz; Dudschig, Carolin; Kaup, Barbara

    2016-01-01

    In distributional semantics models (DSMs) such as latent semantic analysis (LSA), words are represented as vectors in a high-dimensional vector space. This allows for computing word similarities as the cosine of the angle between two such vectors. In two experiments, we investigated whether LSA cosine similarities predict priming effects, in that higher cosine similarities are associated with shorter reaction times (RTs). Critically, we applied a pseudo-random procedure in generating the item material to ensure that we directly manipulated LSA cosines as an independent variable. We employed two lexical priming experiments with lexical decision tasks (LDTs). In Experiment 1 we presented participants with 200 different prime words, each paired with one unique target. We found a significant effect of cosine similarities on RTs. The same was true for Experiment 2, where we reversed the prime-target order (primes of Experiment 1 were targets in Experiment 2, and vice versa). The results of these experiments confirm that LSA cosine similarities can predict priming effects, supporting the view that they are psychologically relevant. The present study thereby provides evidence for qualifying LSA cosine similarities not only as a linguistic measure, but also as a cognitive similarity measure. However, it is also shown that other DSMs can outperform LSA as a predictor of priming effects.

  17. Homebirth and independent midwifery.

    PubMed

    Harris, G

    2000-07-01

    Why do women choose to give birth at home, and midwives to work independently, in a culture that does little to support this option? This article looks at the reasons childbearing women and midwives make these choices and the barriers to achieving them. The safety of the homebirth option is supported in reference to analysis of mortality and morbidity. Homebirth practices and level of success are compared in Australia and New Zealand (NZ), in particular, and The Netherlands, England and America. The success of popularity of homebirths is analysed in terms of socio-economic status. The current situation and challenges of independent midwifery in Darwin are described.

  18. Similarity-Detection and Localization

    NASA Astrophysics Data System (ADS)

    Hwa, T.; Lässig, M.

    1996-03-01

    Assessing the similarities among long sequences of alphabets is a challenging task often encountered in molecular biology. The goal is to find the optimal alignment of sequences and evaluate the statistical significance of the similarities. Here we show that the sequence alignment process is equivalent to finding the optimal trajectory of a directed path in a random potential. Correlations among sequences act as an attractive (columnar) potential well which tends to localize the directed path. On the otherhand, transmission/transcription ``errors'' such as bit flips and random insertions/deletions lead to random potentials which tend to delocalize the directed path. The process of signal recognition is thus shown to be a localization phenomenon. The existence of the disorder-induced localization-delocalization transition gives a well-defined statistical notion to signal recognition. Analytic solution of this problem can be used as a guide to locate optimal parameters in the alignment of macromolecular sequences such as DNA's and proteins.

  19. Active browsing using similarity pyramids

    NASA Astrophysics Data System (ADS)

    Chen, Jau-Yuen; Bouman, Charles A.; Dalton, John C.

    1998-12-01

    In this paper, we describe a new approach to managing large image databases, which we call active browsing. Active browsing integrates relevance feedback into the browsing environment, so that users can modify the database's organization to suit the desired task. Our method is based on a similarity pyramid data structure, which hierarchically organizes the database, so that it can be efficiently browsed. At coarse levels, the similarity pyramid allows users to view the database as large clusters of similar images. Alternatively, users can 'zoom into' finer levels to view individual images. We discuss relevance feedback for the browsing process, and argue that it is fundamentally different from relevance feedback for more traditional search-by-query tasks. We propose two fundamental operations for active browsing: pruning and reorganization. Both of these operations depend on a user-defined relevance set, which represents the image or set of images desired by the user. We present statistical methods for accurately pruning the database, and we propose a new 'worm hole' distance metric for reorganizing the database, so that members of the relevance set are grouped together.

  20. Caring about Independent Lives

    ERIC Educational Resources Information Center

    Christensen, Karen

    2010-01-01

    With the rhetoric of independence, new cash for care systems were introduced in many developed welfare states at the end of the 20th century. These systems allow local authorities to pay people who are eligible for community care services directly, to enable them to employ their own careworkers. Despite the obvious importance of the careworker's…

  1. Postcard from Independence, Mo.

    ERIC Educational Resources Information Center

    Archer, Jeff

    2004-01-01

    This article reports results showing that the Independence, Missori school district failed to meet almost every one of its improvement goals under the No Child Left Behind Act. The state accreditation system stresses improvement over past scores, while the federal law demands specified amounts of annual progress toward the ultimate goal of 100…

  2. Independent Video in Britain.

    ERIC Educational Resources Information Center

    Stewart, David

    Maintaining the status quo as well as the attitude toward cultural funding and development that it imposes on video are detrimental to the formation of a thriving video network, and also out of key with the present social and political situation in Britain. Independent video has some quite specific advantages as a medium for cultural production…

  3. Independent Living Course

    ERIC Educational Resources Information Center

    Tipping, Joyce

    1978-01-01

    Designed to help handicapped persons who have been living a sheltered existence develop independent living skills, this course is divided into two parts. The first part consists of a five-day apartment live-in experience, and the second concentrates on developing the learners' awareness of community resources and consumer skills. (BM)

  4. Native American Independent Living.

    ERIC Educational Resources Information Center

    Clay, Julie Anna

    1992-01-01

    Examines features of independent living philosophy with regard to compatibility with Native American cultures, including definition or conceptualization of disability; self-advocacy; systems advocacy; peer counseling; and consumer control and involvement. Discusses an actualizing process as one method of resolving cultural conflicts and…

  5. Touchstones of Independence.

    ERIC Educational Resources Information Center

    Roha, Thomas Arden

    1999-01-01

    Foundations affiliated with public higher education institutions can avoid having to open records for public scrutiny, by having independent boards of directors, occupying leased office space or paying market value for university space, using only foundation personnel, retaining legal counsel, being forthcoming with information and use of public…

  6. Superresolving multiphoton interferences with independent light sources.

    PubMed

    Oppel, S; Büttner, T; Kok, P; von Zanthier, J

    2012-12-07

    We propose to use multiphoton interferences from statistically independent light sources in combination with linear optical detection techniques to enhance the resolution in imaging. Experimental results with up to five independent thermal light sources confirm this approach to improve the spatial resolution. Since no involved quantum state preparation or detection is required, the experiment can be considered an extension of the Hanbury Brown-Twiss experiment for spatial intensity correlations of order N>2.

  7. [Samuel Hahnemann and the principle of similars].

    PubMed

    Schmidt, Josef M

    2010-01-01

    The principle of similars (treat likes by likes) is generally considered to be one of the pillars of the homeopathic doctrine established by Samuel Hahnemann (1755-1843). Nevertheless, its status and relevance with regard to the practice of homeopathy can be challenged by semantic, conceptual, and epistemological objections. 1. Contrary to its literal meaning, "similia similibus curentur" is commonly used in the sense of "all diseases should be treated by similar drug diseases", thus transgressing its original field of indication. 2. From 1796, when Hahnemann published his first definition of the principle of similars, he gradually raised his claims from merely suggesting a heuristic principle for finding new curative remedies to insisting on having discovered a law of nature and the only true way of healing, in 1807/1808. To substantiate his ambitious tenets, Hahnemann had to introduce a variety of theories which in turn were to become the main battleground in the ensuing controversy about homeopathy. 3. From the perspective of epistemology of science, science can never consist of a final set of absolute truths or the like but must rather be described as a continuous social process that retains a methodological cycle of abduction, deduction, and induction. From the perspective of theory of medicine, however, medicine is to be considered as a practical rather than a cognitive science in its own right. Its first concern ought to be the development of practical directions for treating patients, while the value of competing theories can only be judged from their usefulness in practice. Hence, even though Hahnemann's theories, including his conception of the principle of similars, may be untenable or outdated, the genuine method of homeopathic treatment he founded remains independent of and unaffected by criticism at the level of theory and concepts.

  8. Application of the principle of similarity fluid mechanics

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Sengers, J. V.

    1979-01-01

    Possible applications of the principle of similarity to fluid mechanics is described and illustrated. In correlating thermophysical properties of fluids, the similarity principle transcends the traditional corresponding states principle. In fluid mechanics the similarity principle is useful in correlating flow processes that can be modeled adequately with one independent variable (i.e., one-dimensional flows). In this paper we explore the concept of transforming the conservation equations by combining similarity principles for thermophysical properties with those for fluid flow. We illustrate the usefulness of the procedure by applying such a transformation to calculate two phase critical mass flow through a nozzle.

  9. Lemurs and macaques show similar numerical sensitivity

    PubMed Central

    Jones, Sarah M.; Pearson, John; DeWind, Nicholas K.; Paulsen, David; Tenekedjieva, Ana-Maria; Brannon, Elizabeth M.

    2013-01-01

    We investigated the precision of the approximate number system (ANS) in three lemur species (Lemur catta, Eulemur mongoz, and Eulemur macaco flavifrons), one Old World monkey species (Macaca mulatta) and humans (Homo sapiens). In Experiment 1, four individuals of each nonhuman primate species were trained to select the numerically larger of two visual arrays on a touchscreen. We estimated numerical acuity by modeling Weber fractions (w) and found quantitatively equivalent performance among all four nonhuman primate species. In Experiment 2, we tested adult humans in a similar procedure, and they outperformed the four nonhuman species but showed qualitatively similar performance. These results indicate that the ANS is conserved over the primate order. PMID:24068469

  10. Global picture of self-similar and non-self-similar decay in Burgers turbulence.

    PubMed

    Noullez, Alain; Gurbatov, Sergey N; Aurell, Erik; Simdyankin, Sergey I

    2005-05-01

    This paper continues earlier investigations of the decay of Burgers turbulence in one dimension from Gaussian random initial conditions of the power-law spectral type E0(k) approximately |k|(n). Depending on the power n , different characteristic regions are distinguished. The main focus of this paper is to delineate the regions in wave number k and time t in which self-similarity can (and cannot) be observed, taking into account small-k and large-k cutoffs. The evolution of the spectrum can be inferred using physical arguments describing the competition between the initial spectrum and the new frequencies generated by the dynamics. For large wave numbers, we always have a k(-2) region, associated with the shocks. When n is less than 1, the large-scale part of the spectrum is preserved in time and the global evolution is self-similar, so that scaling arguments perfectly predict the behavior in time of the energy and integral scale. If n is larger than 2, the spectrum tends for long times to a universal scaling form independent of the initial conditions, with universal behavior k(2) at small wave numbers. In the interval 2similar, independent of n and with universal behavior k(2) at small wave number. When 1independent constant; second, a k(2) region at intermediate wave numbers; finally, the usual k(-2) region. In the remaining interval n<-3 the small-k cutoff dominates and n also plays no role. We find also (numerically) the subleading term approximately k(2) in the evolution of the spectrum in the interval -3

  11. Methods to Calculate Spectrum Similarity.

    PubMed

    Yilmaz, Şule; Vandermarliere, Elien; Martens, Lennart

    2017-01-01

    Scoring functions that assess spectrum similarity play a crucial role in many computational mass spectrometry algorithms. These functions are used to compare an experimentally acquired fragmentation (MS/MS) spectrum against two different types of target MS/MS spectra: either against a theoretical MS/MS spectrum derived from a peptide from a sequence database, or against another, previously acquired MS/MS spectrum. The former is typically encountered in database searching, while the latter is used in spectrum clustering and spectral library searching. The comparison between acquired versus theoretical MS/MS spectra is most commonly performed using cross-correlations or probability derived scoring functions, while the comparison of two acquired MS/MS spectra typically makes use of a normalized dot product, especially in spectrum library search algorithms. In addition to these scoring functions, Pearson's or Spearman's correlation coefficients, mean squared error, or median absolute deviation scores can also be used for the same purpose. Here, we describe and evaluate these scoring functions with regards to their ability to assess spectrum similarity for theoretical versus acquired, and acquired versus acquired spectra.

  12. Mechanisms for similarity based cooperation

    NASA Astrophysics Data System (ADS)

    Traulsen, A.

    2008-06-01

    Cooperation based on similarity has been discussed since Richard Dawkins introduced the term “green beard” effect. In these models, individuals cooperate based on an aribtrary signal (or tag) such as the famous green beard. Here, two different models for such tag based cooperation are analysed. As neutral drift is important in both models, a finite population framework is applied. The first model, which we term “cooperative tags” considers a situation in which groups of cooperators are formed by some joint signal. Defectors adopting the signal and exploiting the group can lead to a breakdown of cooperation. In this case, conditions are derived under which the average abundance of the more cooperative strategy exceeds 50%. The second model considers a situation in which individuals start defecting towards others that are not similar to them. This situation is termed “defective tags”. It is shown that in this case, individuals using tags to cooperate exclusively with their own kind dominate over unconditional cooperators.

  13. Generalization, similarity, and Bayesian inference.

    PubMed

    Tenenbaum, J B; Griffiths, T L

    2001-08-01

    Shepard has argued that a universal law should govern generalization across different domains of perception and cognition, as well as across organisms from different species or even different planets. Starting with some basic assumptions about natural kinds, he derived an exponential decay function as the form of the universal generalization gradient, which accords strikingly well with a wide range of empirical data. However, his original formulation applied only to the ideal case of generalization from a single encountered stimulus to a single novel stimulus, and for stimuli that can be represented as points in a continuous metric psychological space. Here we recast Shepard's theory in a more general Bayesian framework and show how this naturally extends his approach to the more realistic situation of generalizing from multiple consequential stimuli with arbitrary representational structure. Our framework also subsumes a version of Tversky's set-theoretic model of similarity, which is conventionally thought of as the primary alternative to Shepard's continuous metric space model of similarity and generalization. This unification allows us not only to draw deep parallels between the set-theoretic and spatial approaches, but also to significantly advance the explanatory power of set-theoretic models.

  14. Effect of similarity between patterns in associative memory

    NASA Astrophysics Data System (ADS)

    Wang, Sheng-Jun; Yang, Zhou

    2017-01-01

    We study the stability of patterns in Hopfield networks in which a part of memorized patterns are similar. The similarity between patterns impacts the stability of these patterns, but the stability of other independent patterns is only changed slightly. We show that the stability of patterns is affected in different ways by similarity. For networks storing a number of patterns, the similarity between patterns enhances the pattern stability. However, the stability of patterns can be weakened by the similarity when networks store fewer patterns, and the relation between the stability of patterns and similarity is nonmonotonic. We present a theoretical explanation of the effect of similarity on stability using signal-to-noise-ratio analysis.

  15. Effect of similarity between patterns in associative memory.

    PubMed

    Wang, Sheng-Jun; Yang, Zhou

    2017-01-01

    We study the stability of patterns in Hopfield networks in which a part of memorized patterns are similar. The similarity between patterns impacts the stability of these patterns, but the stability of other independent patterns is only changed slightly. We show that the stability of patterns is affected in different ways by similarity. For networks storing a number of patterns, the similarity between patterns enhances the pattern stability. However, the stability of patterns can be weakened by the similarity when networks store fewer patterns, and the relation between the stability of patterns and similarity is nonmonotonic. We present a theoretical explanation of the effect of similarity on stability using signal-to-noise-ratio analysis.

  16. Interneurons targeting similar layers receive synaptic inputs with similar kinetics.

    PubMed

    Cossart, Rosa; Petanjek, Zdravko; Dumitriu, Dani; Hirsch, June C; Ben-Ari, Yehezkel; Esclapez, Monique; Bernard, Christophe

    2006-01-01

    GABAergic interneurons play diverse and important roles in controlling neuronal network dynamics. They are characterized by an extreme heterogeneity morphologically, neurochemically, and physiologically, but a functionally relevant classification is still lacking. Present taxonomy is essentially based on their postsynaptic targets, but a physiological counterpart to this classification has not yet been determined. Using a quantitative analysis based on multidimensional clustering of morphological and physiological variables, we now demonstrate a strong correlation between the kinetics of glutamate and GABA miniature synaptic currents received by CA1 hippocampal interneurons and the laminar distribution of their axons: neurons that project to the same layer(s) receive synaptic inputs with similar kinetics distributions. In contrast, the kinetics distributions of GABAergic and glutamatergic synaptic events received by a given interneuron do not depend upon its somatic location or dendritic arborization. Although the mechanisms responsible for this unexpected observation are still unclear, our results suggest that interneurons may be programmed to receive synaptic currents with specific temporal dynamics depending on their targets and the local networks in which they operate.

  17. Phylogenetically related and ecologically similar carnivores harbour similar parasite assemblages.

    PubMed

    Huang, Shan; Bininda-Emonds, Olaf R P; Stephens, Patrick R; Gittleman, John L; Altizer, Sonia

    2014-05-01

    Most parasites infect multiple hosts, but what factors determine the range of hosts a given parasite can infect? Understanding the broad scale determinants of parasite distributions across host lineages is important for predicting pathogen emergence in new hosts and for estimating pathogen diversity in understudied host species. In this study, we used a new data set on 793 parasite species reported from free-ranging populations of 64 carnivore species to examine the factors that influence parasite sharing between host species. Our results showed that parasites are more commonly shared between phylogenetically related host species pairs. Additionally, host species with higher similarity in biological traits and greater geographic range overlap were also more likely to share parasite species. Of three measures of phylogenetic relatedness considered here, the number divergence events that separated host species pairs most strongly influenced the likelihood of parasite sharing. We also showed that viruses and helminths tend to infect carnivore hosts within more restricted phylogenetic ranges than expected by chance. Overall, our results underscore the importance of host evolutionary history in determining parasite host range, even when simultaneously considering other factors such as host ecology and geographic distribution.

  18. Random Independence Systems

    DTIC Science & Technology

    1981-11-01

    Whitney provided a set of axioms for a structure commonly called i a matroid. Matroid theory (see ( Tutte , 19711, [Lawler, 19761) has applications to a wide...applicable in this case. On the other hand, there is no known efficient ( polynomial time) algorithm for constructing cliques of size 2 log n with...intersection. The problem of constructing a maximal independent set in the intersection of k matroids has a polynomial time (in tEl) algorithm [Lawler, 197

  19. Similarity and scale in catchment storm response

    NASA Technical Reports Server (NTRS)

    Wood, Eric F.; Sivapalan, Murugesu; Beven, Keith

    1993-01-01

    Until recently, very little progress had been made in understanding the relationship between small-scale variability of topography, soil, and rainfalls and the storm response seen at the catchment scale. The work reviewed here represents the first attempt at a systematic theoretical framework for such understanding in the context of surface runoff generation by different processes. The parameterization of hydrological processes over a range of scales is examined, and the concept of the 'representative elementary area' (REA) is introduced. The REA is a fundamental scale for catchment modeling at which continuum assumptions can be applied for the spatially variable controls and parameters, and spatial patterns no longer have to be considered explicitly. The investigation of scale leads into the concept of hydrologic similarity in which the effects of the environmental controls on runoff generation and flood frequency response be investigated independently of catchment scale. The paper reviews the authors' initial results and hopefully will motivate others to also investigate the issues of hydrologic scale and similarity.

  20. Agent independent task planning

    NASA Technical Reports Server (NTRS)

    Davis, William S.

    1990-01-01

    Agent-Independent Planning is a technique that allows the construction of activity plans without regard to the agent that will perform them. Once generated, a plan is then validated and translated into instructions for a particular agent, whether a robot, crewmember, or software-based control system. Because Space Station Freedom (SSF) is planned for orbital operations for approximately thirty years, it will almost certainly experience numerous enhancements and upgrades, including upgrades in robotic manipulators. Agent-Independent Planning provides the capability to construct plans for SSF operations, independent of specific robotic systems, by combining techniques of object oriented modeling, nonlinear planning and temporal logic. Since a plan is validated using the physical and functional models of a particular agent, new robotic systems can be developed and integrated with existing operations in a robust manner. This technique also provides the capability to generate plans for crewmembers with varying skill levels, and later apply these same plans to more sophisticated robotic manipulators made available by evolutions in technology.

  1. International exploration by independent

    SciTech Connect

    Bertragne, R.G.

    1992-04-01

    Recent industry trends indicate that the smaller U.S. independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. Foreign finding costs per barrel usually are accepted to be substantially lower than domestic costs because of the large reserve potential of international plays. To get involved in overseas exploration, however, requires the explorationist to adapt to different cultural, financial, legal, operational, and political conditions. Generally, foreign exploration proceeds at a slower pace than domestic exploration because concessions are granted by a country's government, or are explored in partnership with a national oil company. First, the explorationist must prepare a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company; next, is an ongoing evaluation of quality prospects in various sedimentary basins, and careful planning and conduct of the operations. To successfully explore overseas also requires the presence of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work. Ideally, these team members will have had a considerable amount of on-site experience in various countries and climates. Independents best suited for foreign expansion are those who have been financially successful in domestic exploration. When properly approached, foreign exploration is well within the reach of smaller U.S. independents, and presents essentially no greater risk than domestic exploration; however, the reward can be much larger and can catapult the company into the 'big leagues.'

  2. International exploration by independents

    SciTech Connect

    Bertagne, R.G. )

    1991-03-01

    Recent industry trends indicate that the smaller US independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. It is usually accepted that foreign finding costs per barrel are substantially lower than domestic because of the large reserve potential of international plays. To get involved overseas requires, however, an adaptation to different cultural, financial, legal, operational, and political conditions. Generally foreign exploration proceeds at a slower pace than domestic because concessions are granted by the government, or are explored in partnership with the national oil company. First, a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company, must be prepared; it must be followed by an ongoing evaluation of quality prospects in various sedimentary basins, and a careful planning and conduct of the operations. To successfully explore overseas also requires the presence on the team of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work, having had a considerable amount of onsite experience in various geographical and climatic environments. Independents that are best suited for foreign expansion are those that have been financially successful domestically, and have a good discovery track record. When properly approached foreign exploration is well within the reach of smaller US independents and presents essentially no greater risk than domestic exploration; the reward, however, can be much larger and can catapult the company into the big leagues.

  3. Semantically enabled image similarity search

    NASA Astrophysics Data System (ADS)

    Casterline, May V.; Emerick, Timothy; Sadeghi, Kolia; Gosse, C. A.; Bartlett, Brent; Casey, Jason

    2015-05-01

    Georeferenced data of various modalities are increasingly available for intelligence and commercial use, however effectively exploiting these sources demands a unified data space capable of capturing the unique contribution of each input. This work presents a suite of software tools for representing geospatial vector data and overhead imagery in a shared high-dimension vector or embedding" space that supports fused learning and similarity search across dissimilar modalities. While the approach is suitable for fusing arbitrary input types, including free text, the present work exploits the obvious but computationally difficult relationship between GIS and overhead imagery. GIS is comprised of temporally-smoothed but information-limited content of a GIS, while overhead imagery provides an information-rich but temporally-limited perspective. This processing framework includes some important extensions of concepts in literature but, more critically, presents a means to accomplish them as a unified framework at scale on commodity cloud architectures.

  4. Path similarity skeleton graph matching.

    PubMed

    Bai, Xiang; Latecki, Longin Jan

    2008-07-01

    This paper presents a novel framework to for shape recognition based on object silhouettes. The main idea is to match skeleton graphs by comparing the shortest paths between skeleton endpoints. In contrast to typical tree or graph matching methods, we completely ignore the topological graph structure. Our approach is motivated by the fact that visually similar skeleton graphs may have completely different topological structures. The proposed comparison of shortest paths between endpoints of skeleton graphs yields correct matching results in such cases. The skeletons are pruned by contour partitioning with Discrete Curve Evolution, which implies that the endpoints of skeleton branches correspond to visual parts of the objects. The experimental results demonstrate that our method is able to produce correct results in the presence of articulations, stretching, and occlusion.

  5. Critical Branches and Lucky Loads in Control-Independence Architectures

    ERIC Educational Resources Information Center

    Malik, Kshitiz

    2009-01-01

    Branch mispredicts have a first-order impact on the performance of integer applications. Control Independence (CI) architectures aim to overlap the penalties of mispredicted branches with useful execution by spawning control-independent work as separate threads. Although control independent, such threads may consume register and memory values…

  6. Critical Branches and Lucky Loads in Control-Independence Architectures

    ERIC Educational Resources Information Center

    Malik, Kshitiz

    2009-01-01

    Branch mispredicts have a first-order impact on the performance of integer applications. Control Independence (CI) architectures aim to overlap the penalties of mispredicted branches with useful execution by spawning control-independent work as separate threads. Although control independent, such threads may consume register and memory values…

  7. Independent EEG Sources Are Dipolar

    PubMed Central

    Delorme, Arnaud; Palmer, Jason; Onton, Julie; Oostenveld, Robert; Makeig, Scott

    2012-01-01

    Independent component analysis (ICA) and blind source separation (BSS) methods are increasingly used to separate individual brain and non-brain source signals mixed by volume conduction in electroencephalographic (EEG) and other electrophysiological recordings. We compared results of decomposing thirteen 71-channel human scalp EEG datasets by 22 ICA and BSS algorithms, assessing the pairwise mutual information (PMI) in scalp channel pairs, the remaining PMI in component pairs, the overall mutual information reduction (MIR) effected by each decomposition, and decomposition ‘dipolarity’ defined as the number of component scalp maps matching the projection of a single equivalent dipole with less than a given residual variance. The least well-performing algorithm was principal component analysis (PCA); best performing were AMICA and other likelihood/mutual information based ICA methods. Though these and other commonly-used decomposition methods returned many similar components, across 18 ICA/BSS algorithms mean dipolarity varied linearly with both MIR and with PMI remaining between the resulting component time courses, a result compatible with an interpretation of many maximally independent EEG components as being volume-conducted projections of partially-synchronous local cortical field activity within single compact cortical domains. To encourage further method comparisons, the data and software used to prepare the results have been made available (http://sccn.ucsd.edu/wiki/BSSComparison). PMID:22355308

  8. A Student Guide for Independent Study Telecourses.

    ERIC Educational Resources Information Center

    Chavez, Mauro

    Designed for students enrolled in telecourses offered by Evergreen Valley College (EVC) on an independent study basis, this guide explains the role of telecourses in the college curriculum, differences and similarities between telecourses and traditional courses, procedures for contacting instructors, and the roles of the college and the student…

  9. A Student Guide for Independent Study Telecourses.

    ERIC Educational Resources Information Center

    Chavez, Mauro

    Designed for students enrolled in telecourses offered by Evergreen Valley College (EVC) on an independent study basis, this guide explains the role of telecourses in the college curriculum, differences and similarities between telecourses and traditional courses, procedures for contacting instructors, and the roles of the college and the student…

  10. APoc: large-scale identification of similar protein pockets

    PubMed Central

    Gao, Mu; Skolnick, Jeffrey

    2013-01-01

    Motivation: Most proteins interact with small-molecule ligands such as metabolites or drug compounds. Over the past several decades, many of these interactions have been captured in high-resolution atomic structures. From a geometric point of view, most interaction sites for grasping these small-molecule ligands, as revealed in these structures, form concave shapes, or ‘pockets’, on the protein’s surface. An efficient method for comparing these pockets could greatly assist the classification of ligand-binding sites, prediction of protein molecular function and design of novel drug compounds. Results: We introduce a computational method, APoc (Alignment of Pockets), for the large-scale, sequence order-independent, structural comparison of protein pockets. A scoring function, the Pocket Similarity Score (PS-score), is derived to measure the level of similarity between pockets. Statistical models are used to estimate the significance of the PS-score based on millions of comparisons of randomly related pockets. APoc is a general robust method that may be applied to pockets identified by various approaches, such as ligand-binding sites as observed in experimental complex structures, or predicted pockets identified by a pocket-detection method. Finally, we curate large benchmark datasets to evaluate the performance of APoc and present interesting examples to demonstrate the usefulness of the method. We also demonstrate that APoc has better performance than the geometric hashing-based method SiteEngine. Availability and implementation: The APoc software package including the source code is freely available at http://cssb.biology.gatech.edu/APoc. Contact: skolnick@gatech.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:23335017

  11. Suffix Ordering and Morphological Processing

    ERIC Educational Resources Information Center

    Plag, Ingo; Baayen, Harald

    2009-01-01

    There is a long-standing debate about the principles constraining the combinatorial properties of suffixes. Hay 2002 and Hay & Plag 2004 proposed a model in which suffixes can be ordered along a hierarchy of processing complexity. We show that this model generalizes to a larger set of suffixes, and we provide independent evidence supporting the…

  12. Suffix Ordering and Morphological Processing

    ERIC Educational Resources Information Center

    Plag, Ingo; Baayen, Harald

    2009-01-01

    There is a long-standing debate about the principles constraining the combinatorial properties of suffixes. Hay 2002 and Hay & Plag 2004 proposed a model in which suffixes can be ordered along a hierarchy of processing complexity. We show that this model generalizes to a larger set of suffixes, and we provide independent evidence supporting the…

  13. Similarity Rules for Scaling Solar Sail Systems

    NASA Technical Reports Server (NTRS)

    Canfield, Stephen L.; Beard, James W., III; Peddieson, John; Ewing, Anthony; Garbe, Greg

    2004-01-01

    Future science missions will require solar sails on the order 10,000 sq m (or larger). However, ground and flight demonstrations must be conducted at significantly smaller Sizes (400 sq m for ground demo) due to limitations of ground-based facilities and cost and availability of flight opportunities. For this reason, the ability to understand the process of scalability, as it applies to solar sail system models and test data, is crucial to the advancement of this technology. This report will address issues of scaling in solar sail systems, focusing on structural characteristics, by developing a set of similarity or similitude functions that will guide the scaling process. The primary goal of these similarity functions (process invariants) that collectively form a set of scaling rules or guidelines is to establish valid relationships between models and experiments that are performed at different orders of scale. In the near term, such an effort will help guide the size and properties of a flight validation sail that will need to be flown to accurately represent a large, mission-level sail.

  14. FRESCO: Referential compression of highly similar sequences.

    PubMed

    Wandelt, Sebastian; Leser, Ulf

    2013-01-01

    In many applications, sets of similar texts or sequences are of high importance. Prominent examples are revision histories of documents or genomic sequences. Modern high-throughput sequencing technologies are able to generate DNA sequences at an ever-increasing rate. In parallel to the decreasing experimental time and cost necessary to produce DNA sequences, computational requirements for analysis and storage of the sequences are steeply increasing. Compression is a key technology to deal with this challenge. Recently, referential compression schemes, storing only the differences between a to-be-compressed input and a known reference sequence, gained a lot of interest in this field. In this paper, we propose a general open-source framework to compress large amounts of biological sequence data called Framework for REferential Sequence COmpression (FRESCO). Our basic compression algorithm is shown to be one to two orders of magnitudes faster than comparable related work, while achieving similar compression ratios. We also propose several techniques to further increase compression ratios, while still retaining the advantage in speed: 1) selecting a good reference sequence; and 2) rewriting a reference sequence to allow for better compression. In addition,we propose a new way of further boosting the compression ratios by applying referential compression to already referentially compressed files (second-order compression). This technique allows for compression ratios way beyond state of the art, for instance,4,000:1 and higher for human genomes. We evaluate our algorithms on a large data set from three different species (more than 1,000 genomes, more than 3 TB) and on a collection of versions of Wikipedia pages. Our results show that real-time compression of highly similar sequences at high compression ratios is possible on modern hardware.

  15. Immunological Similarities of Proteinase Inhibitors from Potatoes 1

    PubMed Central

    Ryan, Clarence A.; Santarius, Karlheinz

    1976-01-01

    Proteinase inhibitors, purified independently from Japanese, United States, and German potato varieties, and having different physicochemical and inhibitory properties, are shown to be immunochemically similar. These results indicate that the heterogeneity found among proteinase inhibitors from potato tubers is apparently due both to intervarietal, as well as intravarietal, variations in isoinhibitor components. Images PMID:16659744

  16. Scientific independence: A key to credibility

    Treesearch

    Leonard F. Ruggiero

    2007-01-01

    Independence and objectivity are key ingredients of scientific credibility, especially in research organizations that are part of a natural resource management agency like the Forest Service. Credibility, in turn, is essential to the utility of scientific information in socio-political processes. In order to develop this thesis further, a basic understanding of Forest...

  17. Cary Potter on Independent Education

    ERIC Educational Resources Information Center

    Potter, Cary

    1978-01-01

    Cary Potter was President of the National Association of Independent Schools from 1964-1978. As he leaves NAIS he gives his views on education, on independence, on the independent school, on public responsibility, on choice in a free society, on educational change, and on the need for collective action by independent schools. (Author/RK)

  18. Sensation Seeking and Field Independence.

    ERIC Educational Resources Information Center

    Baker, A. Harvey

    1988-01-01

    Examined relationship between sensation seeking and field independence using three indices of field independence and combining the data in an Overall Index. The three field independence instruments and the Sensation Seeking Scale were administered to 103 college students. Positive relationship between sensation seeking and field independence was…

  19. Cary Potter on Independent Education

    ERIC Educational Resources Information Center

    Potter, Cary

    1978-01-01

    Cary Potter was President of the National Association of Independent Schools from 1964-1978. As he leaves NAIS he gives his views on education, on independence, on the independent school, on public responsibility, on choice in a free society, on educational change, and on the need for collective action by independent schools. (Author/RK)

  20. Myth or Truth: Independence Day.

    ERIC Educational Resources Information Center

    Gardner, Traci

    Most Americans think of the Fourth of July as Independence Day, but is it really the day the U.S. declared and celebrated independence? By exploring myths and truths surrounding Independence Day, this lesson asks students to think critically about commonly believed stories regarding the beginning of the Revolutionary War and the Independence Day…

  1. Explosion Source Similarity Analysis via SVD

    NASA Astrophysics Data System (ADS)

    Yedlin, Matthew; Ben Horin, Yochai; Margrave, Gary

    2016-04-01

    An important seismological ingredient for establishing a regional seismic nuclear discriminant is the similarity analysis of a sequence of explosion sources. To investigate source similarity, we are fortunate to have access to a sequence of 1805 three-component recordings of quarry blasts, shot from March 2002 to January 2015. The centroid of these blasts has an estimated location 36.3E and 29.9N. All blasts were detonated by JPMC (Jordan Phosphate Mines Co.) All data were recorded at the Israeli NDC, HFRI, located at 30.03N and 35.03E. Data were first winnowed based on the distribution of maximum amplitudes in the neighborhood of the P-wave arrival. The winnowed data were then detrended using the algorithm of Cleveland et al (1990). The detrended data were bandpass filtered between .1 to 12 Hz using an eighth order Butterworth filter. Finally, data were sorted based on maximum trace amplitude. Two similarity analysis approaches were used. First, for each component, the entire suite of traces was decomposed into its eigenvector representation, by employing singular-valued decomposition (SVD). The data were then reconstructed using 10 percent of the singular values, with the resulting enhancement of the S-wave and surface wave arrivals. The results of this first method are then compared to the second analysis method based on the eigenface decomposition analysis of Turk and Pentland (1991). While both methods yield similar results in enhancement of data arrivals and reduction of data redundancy, more analysis is required to calibrate the recorded data to charge size, a quantity that was not available for the current study. References Cleveland, R. B., Cleveland, W. S., McRae, J. E., and Terpenning, I., Stl: A seasonal-trend decomposition procedure based on loess, Journal of Official Statistics, 6, No. 1, 3-73, 1990. Turk, M. and Pentland, A., Eigenfaces for recognition. Journal of cognitive neuroscience, 3(1), 71-86, 1991.

  2. Optimal dynamic discrimination of similar quantum systems

    NASA Astrophysics Data System (ADS)

    Li, Baiqing

    2005-07-01

    The techniques for identifying and separating similar molecules have always been very important to chemistry and other branches of science and engineering. Similar quantum systems share comparable Hamiltonians, so their eigenenergy levels, transition dipole moments, and therefore their ordinary observable properties are alike. Traditional analytical methods have mostly been restricted by working with the subtle differences in the physical and chemical properties of the similar species. Optimal Dynamic Discrimination (ODD) aims at magnifying the dissimilarity of the agents by actively controlling their quantum evolution, drawing on the extremely rich information embedded in their dynamics. ODD is developed based on the tremendous flexibility of Optimal Control Theory (OCT) and on the practical implementation of closed-loop learning control, which has become a more and more indispensable tool for controlling quantum processes. The ODD experimental paradigm is designed to combat a number of factors that are detrimental to the discrimination of similar molecules: laser pulse noise, signal detection errors, finite time resolution in the signals, and environmental decoherence effects. It utilizes either static signals or time series signal, the latter capable of providing more information. Simulations are performed in this dissertation progressing from the wave function to the density matrix formulation, in order to study the decoherence effects. Analysis of the results reveals the roles of the adverse factors, unravels the underlying mechanisms of ODD, and provides insights on laboratory implementation. ODD emphasizes the incorporation of algorithmic development and laboratory design, and seeks to bridge the gap between theoretical/computational chemistry and experimental chemistry, with the help from applied mathematics and computer science.

  3. Similarity metrics for surgical process models.

    PubMed

    Neumuth, Thomas; Loebe, Frank; Jannin, Pierre

    2012-01-01

    The objective of this work is to introduce a set of similarity metrics for comparing surgical process models (SPMs). SPMs are progression models of surgical interventions that support quantitative analyses of surgical activities, supporting systems engineering or process optimization. Five different similarity metrics are presented and proven. These metrics deal with several dimensions of process compliance in surgery, including granularity, content, time, order, and frequency of surgical activities. The metrics were experimentally validated using 20 clinical data sets each for cataract interventions, craniotomy interventions, and supratentorial tumor resections. The clinical data sets were controllably modified in simulations, which were iterated ten times, resulting in a total of 600 simulated data sets. The simulated data sets were subsequently compared to the original data sets to empirically assess the predictive validity of the metrics. We show that the results of the metrics for the surgical process models correlate significantly (p<0.001) with the induced modifications and that all metrics meet predictive validity. The clinical use of the metrics was exemplarily, as demonstrated by assessment of the learning curves of observers during surgical process model acquisition. Measuring similarity between surgical processes is a complex task. However, metrics for computing the similarity between surgical process models are needed in many uses in the field of medical engineering. These metrics are essential whenever two SPMs need to be compared, such as during the evaluation of technical systems, the education of observers, or the determination of surgical strategies. These metrics are key figures that provide a solid base for medical decisions, such as during validation of sensor systems for use in operating rooms in the future. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Reflections on independence in nurse practitioner practice.

    PubMed

    Weiland, Sandra A

    2008-07-01

    To examine factors that influence the ability of nurse practitioners (NPs) to practice as independent primary care providers. Extensive literature search on CINAHL, OVID, MEDLINE, Internet journal sources, and professional association Web sites. The legal authority for NPs to practice independently is recognized; however, the ability to put that authority into practice is undermined by the historical failure of political, professional, and social entities to recognize NPs as providers capable of providing primary care autonomously. Nonrecognition is responsible for complex reimbursement policies (both federal and state) that economically and professionally restrain the NP role; hence, NPs remain in a financially dependent relationship despite 40 years of proven safe practice. NPs must articulate their independence as practitioners more vociferously in order to meet society's healthcare requirements, as well as to attain professional fulfillment and forge collegial relationships. NPs will never be seen as members of a profession by either themselves or others without the practicality of independence and autonomy. Although legal independence is a fact, real practice independence in the pragmatic sense is contingent upon reimbursement. Without fiscal sustainability, practice independence is an impossibility. And, without professional autonomy, NPs will have only an employee's voice in the dynamic healthcare system in which they are really key players in providing healthcare services to the poor and undeserved populations.

  5. Mixed-List Phonological Similarity Effects in Delayed Serial Recall

    ERIC Educational Resources Information Center

    Farrell, Simon

    2006-01-01

    Recent experiments have shown that placing dissimilar items on lists of phonologically similar items enhances accuracy of ordered recall of the dissimilar items [Farrell, S., & Lewandowsky, S. (2003). Dissimilar items benefit from phonological similarity in serial recall. "Journal of Experimental Psychology: Learning, Memory, and Cognition," 29,…

  6. The generalized scheme-independent Crewther relation in QCD

    DOE PAGES

    Shen, Jian-Ming; Wu, Xing-Gang; Ma, Yang; ...

    2017-05-10

    The Principle of Maximal Conformality (PMC) provides a systematic way to set the renormalization scales order-by-order for any perturbative QCD calculable processes. The resulting predictions are independent of the choice of renormalization scheme, a requirement of renormalization group invariance. The Crewther relation, which was originally derived as a consequence of conformally invariant field theory, provides a remarkable connection between two observables when the β function vanishes: one can show that the product of the Bjorken sum rule for spin-dependent deep inelastic lepton–nucleon scattering times the Adler function, defined from the cross section for electron–positron annihilation into hadrons, has no pQCD radiative corrections. The “Generalized Crewther Relation” relates these two observables for physical QCD with nonzero β function; specifically, it connects the non-singlet Adler function (Dns) to the Bjorken sum rule coefficient for polarized deep-inelastic electron scattering (CBjp) at leading twist. A scheme-dependent ΔCSB-term appears in the analysis in order to compensate for the conformal symmetry breaking (CSB) terms from perturbative QCD. In conventional analyses, this normally leads to unphysical dependence in both the choice of the renormalization scheme and the choice of the initial scale at any finite order. However, by applying PMC scale-setting, we can fix the scales of the QCD coupling unambiguously at every order of pQCD. The result is that both Dns and the inverse coefficient Cmore » $$-1\\atop{Bjp}$$ have identical pQCD coefficients, which also exactly match the coefficients of the corresponding conformal theory. Thus one obtains a new generalized Crewther relation for QCD which connects two effective charges, $$\\hat{α}$$d(Q)=Σi≥1$$\\hat{α}^i\\atop{g1}$$(Qi), at their respective physical scales. This identity is independent of the choice of the renormalization scheme at any finite order, and the dependence on the

  7. The generalized scheme-independent Crewther relation in QCD

    NASA Astrophysics Data System (ADS)

    Shen, Jian-Ming; Wu, Xing-Gang; Ma, Yang; Brodsky, Stanley J.

    2017-07-01

    The Principle of Maximal Conformality (PMC) provides a systematic way to set the renormalization scales order-by-order for any perturbative QCD calculable processes. The resulting predictions are independent of the choice of renormalization scheme, a requirement of renormalization group invariance. The Crewther relation, which was originally derived as a consequence of conformally invariant field theory, provides a remarkable connection between two observables when the β function vanishes: one can show that the product of the Bjorken sum rule for spin-dependent deep inelastic lepton-nucleon scattering times the Adler function, defined from the cross section for electron-positron annihilation into hadrons, has no pQCD radiative corrections. The ;Generalized Crewther Relation; relates these two observables for physical QCD with nonzero β function; specifically, it connects the non-singlet Adler function (Dns) to the Bjorken sum rule coefficient for polarized deep-inelastic electron scattering (CBjp) at leading twist. A scheme-dependent ΔCSB-term appears in the analysis in order to compensate for the conformal symmetry breaking (CSB) terms from perturbative QCD. In conventional analyses, this normally leads to unphysical dependence in both the choice of the renormalization scheme and the choice of the initial scale at any finite order. However, by applying PMC scale-setting, we can fix the scales of the QCD coupling unambiguously at every order of pQCD. The result is that both Dns and the inverse coefficient CBjp-1 have identical pQCD coefficients, which also exactly match the coefficients of the corresponding conformal theory. Thus one obtains a new generalized Crewther relation for QCD which connects two effective charges, αˆd (Q) =∑i≥1 αˆg1 i (Qi), at their respective physical scales. This identity is independent of the choice of the renormalization scheme at any finite order, and the dependence on the choice of the initial scale is negligible. Similar

  8. Abel's Theorem Simplifies Reduction of Order

    ERIC Educational Resources Information Center

    Green, William R.

    2011-01-01

    We give an alternative to the standard method of reduction or order, in which one uses one solution of a homogeneous, linear, second order differential equation to find a second, linearly independent solution. Our method, based on Abel's Theorem, is shorter, less complex and extends to higher order equations.

  9. The Influences of Group and Independent General Practice on Patient Care

    PubMed Central

    Sellers, E. M.

    1965-01-01

    When the practices of four general practitioners, members of multispecialist-general practitioner salaried groups (clinic doctors) were compared with those of four independent general practitioners (solo practitioners), it was noted that: group practice patients had more office laboratory investigation and greater in-hospital consultation and referral. On the other hand, independent practitioners' patients seemed to receive more personal attention from the doctor, a fuller explanation of diagnosis and treatment during office hours, more drug samples and more laboratory investigation in hospital. Group and independent practices are similar with respect to the rate of follow-up visits, the volume of preventive medicine, the number of radiographs and special procedures, the total number of drugs ordered, and the in-hospital formal written consultation rate and office consultation rate. The similarities between two types of practice may be a result of the interaction of group and independent practice in the same community. It is concluded that the team approach to medical care is not incompatible with independent practice. PMID:14323656

  10. Effect of Number and Similarity on Children's Plural Comprehension

    ERIC Educational Resources Information Center

    Lanter, Jennifer A.; Basche, Richard A.

    2014-01-01

    During the first years of language development, toddlers coordinate multiple cues in order to acquire the plural form. The aim of this study was to manipulate object similarity as well as set size in order to determine whether these variables impact children's comprehension of plurality. One-hundred-and-fifty children ranging in age from 22 to 36…

  11. Effect of Number and Similarity on Children's Plural Comprehension

    ERIC Educational Resources Information Center

    Lanter, Jennifer A.; Basche, Richard A.

    2014-01-01

    During the first years of language development, toddlers coordinate multiple cues in order to acquire the plural form. The aim of this study was to manipulate object similarity as well as set size in order to determine whether these variables impact children's comprehension of plurality. One-hundred-and-fifty children ranging in age from 22 to 36…

  12. Developmental study of similarity judgments involving dimensions.

    PubMed

    Fahrmeier, E D; Medin, D L

    1977-10-01

    In order to examine the nature of dimensional processing in children, kindergarten and third grade children were asked to make similarity judgments for unidimensional sets of stimuli differing in color (hue), size, and shape, respectively. Age differences were generally confined to the color set. The judgments of the older children in their age group than were the younger children's. The frequency of good-fitting scaling solutions was also higher for the older children. The processing of color in a relational manner thus seems to develop more slowly than relational processing of size or shape. Results from any task which depends on or is facilitated by relational processing could be altered by the dimensions used. The methods developed in the paper also provide an alternate method of studying seriation .

  13. Social values as arguments: similar is convincing

    PubMed Central

    Maio, Gregory R.; Hahn, Ulrike; Frost, John-Mark; Kuppens, Toon; Rehman, Nadia; Kamble, Shanmukh

    2014-01-01

    Politicians, philosophers, and rhetors engage in co-value argumentation: appealing to one value in order to support another value (e.g., “equality leads to freedom”). Across four experiments in the United Kingdom and India, we found that the psychological relatedness of values affects the persuasiveness of the arguments that bind them. Experiment 1 found that participants were more persuaded by arguments citing values that fulfilled similar motives than by arguments citing opposing values. Experiments 2 and 3 replicated this result using a wider variety of values, while finding that the effect is stronger among people higher in need for cognition and that the effect is mediated by the greater plausibility of co-value arguments that link motivationally compatible values. Experiment 4 extended the effect to real-world arguments taken from political propaganda and replicated the mediating effect of argument plausibility. The findings highlight the importance of value relatedness in argument persuasiveness. PMID:25147529

  14. Similarities between methamphetamine toxicity and proteasome inhibition.

    PubMed

    Fornai, F; Lenzi, P; Gesi, M; Ferrucci, M; Lazzeri, G; Capobianco, L; de Blasi, A; Battaglia, G; Nicoletti, F; Ruggieri, S; Paparelli, A

    2004-10-01

    The monoamine neurotoxin methamphetamine (METH) is commonly used as an experimental model for Parkinson's disease (PD). In fact, METH-induced striatal dopamine (DA) loss is accompanied by damage to striatal nerve endings arising from the substantia nigra. On the other hand, PD is characterized by neuronal inclusions within nigral DA neurons. These inclusions contain alpha-synuclein, ubiquitin, and various components of a metabolic pathway named the ubiquitin-proteasome (UP) system, while mutation of genes coding for various components of the UP system is responsible for inherited forms of PD. In this presentation we demonstrate for the first time the occurrence of neuronal inclusions in vivo in the nigrostriatal system of the mouse following administration of METH. We analyzed, in vivo and in vitro, the shape and the fine structure of these neuronal bodies by using transmission electron microscopy. Immunocytochemical investigation showed that these METH-induced cytosolic inclusions stain for ubiquitin, alpha-synuclein, and UP-related molecules, thus sharing similar components with Lewy bodies occurring in PD, with an emphasis on enzymes belonging to the UP system. In line with this, blockade of this multicatalytic pathway by the selective inhibitor epoxomycin produced cell inclusions with similar features. Moreover, using a multifaceted pharmacological approach, we could demonstrate the need for endogenous DA in order to form neuronal inclusions.

  15. Similarity Rules for Scaling Solar Sail Systems

    NASA Technical Reports Server (NTRS)

    Canfield, Stephen L.; Peddieson, John; Garbe, Gregory

    2010-01-01

    Future science missions will require solar sails on the order of 200 square meters (or larger). However, ground demonstrations and flight demonstrations must be conducted at significantly smaller sizes, due to limitations of ground-based facilities and cost and availability of flight opportunities. For this reason, the ability to understand the process of scalability, as it applies to solar sail system models and test data, is crucial to the advancement of this technology. This paper will approach the problem of scaling in solar sail models by developing a set of scaling laws or similarity criteria that will provide constraints in the sail design process. These scaling laws establish functional relationships between design parameters of a prototype and model sail that are created at different geometric sizes. This work is applied to a specific solar sail configuration and results in three (four) similarity criteria for static (dynamic) sail models. Further, it is demonstrated that even in the context of unique sail material requirements and gravitational load of earth-bound experiments, it is possible to develop appropriate scaled sail experiments. In the longer term, these scaling laws can be used in the design of scaled experimental tests for solar sails and in analyzing the results from such tests.

  16. Pharmacophore-based similarity scoring for DOCK.

    PubMed

    Jiang, Lingling; Rizzo, Robert C

    2015-01-22

    Pharmacophore modeling incorporates geometric and chemical features of known inhibitors and/or targeted binding sites to rationally identify and design new drug leads. In this study, we have encoded a three-dimensional pharmacophore matching similarity (FMS) scoring function into the structure-based design program DOCK. Validation and characterization of the method are presented through pose reproduction, crossdocking, and enrichment studies. When used alone, FMS scoring dramatically improves pose reproduction success to 93.5% (∼20% increase) and reduces sampling failures to 3.7% (∼6% drop) compared to the standard energy score (SGE) across 1043 protein-ligand complexes. The combined FMS+SGE function further improves success to 98.3%. Crossdocking experiments using FMS and FMS+SGE scoring, for six diverse protein families, similarly showed improvements in success, provided proper pharmacophore references are employed. For enrichment, incorporating pharmacophores during sampling and scoring, in most cases, also yield improved outcomes when docking and rank-ordering libraries of known actives and decoys to 15 systems. Retrospective analyses of virtual screenings to three clinical drug targets (EGFR, IGF-1R, and HIVgp41) using X-ray structures of known inhibitors as pharmacophore references are also reported, including a customized FMS scoring protocol to bias on selected regions in the reference. Overall, the results and fundamental insights gained from this study should benefit the docking community in general, particularly researchers using the new FMS method to guide computational drug discovery with DOCK.

  17. Mass versus molar doses, similarities and differences.

    PubMed

    Chmielewska, A; Lamparczyk, H

    2008-11-01

    Generally, they are two systems expressing the amounts of active substance in a given drug product, i.e. mass and molar dose. Currently, the dose system based on the mass is widely used in which doses are expressed in grams or milligrams. On the other hand, the molar dose system is in direct relation to the number of molecules. Hence, the objective of this work was to compare both systems in order to find their advantages and disadvantages. Active substances belonging to the groups of antibiotics, nootropic agents, beta-blockers, vitamins, GABA-analog, COX-2 inhibitors, calcium channel antagonists, benzodiazepine receptor agonists, lipid-modifying agents (fibrates), non-steroidal anti-inflammatory drugs (profens), estrogens, neuroleptics, analgesics and benzodiazepines were considered. Moreover, products containing two active substances were also taken into account. These are mixtures of hydrochlorothiazide with active substances influencing the renin-angiotensin system and combined oral contraceptives. For each active substance, belonging to the groups mentioned above molar doses were calculated from mass doses and molar mass. Hence, groups of drugs with a single active substance, drugs with similar pharmacological activities, pharmaceutical alternatives, and drugs with a single active ingredient manufactured in different doses were compared in order to find which dose system describes more adequately differences between and within the groups mentioned above. Comparisons were supported by a number of equations, which theoretically justify the data, and relationships derived from calculations.

  18. Voxel similarity measures for automated image registration

    NASA Astrophysics Data System (ADS)

    Hill, Derek L.; Studholme, Colin; Hawkes, David J.

    1994-09-01

    We present the concept of the feature space sequence: 2D distributions of voxel features of two images generated at registration and a sequence of misregistrations. We provide an explanation of the structure seen in these images. Feature space sequences have been generated for a pair of MR image volumes identical apart from the addition of Gaussian noise to one, MR image volumes with and without Gadolinium enhancement, MR and PET-FDG image volumes and MR and CT image volumes, all of the head. The structure seen in the feature space sequences was used to devise two new measures of similarity which in turn were used to produce plots of cost versus misregistration for the 6 degrees of freedom of rigid body motion. One of these, the third order moment of the feature space histogram, was used to register the MR image volumes with and without Gadolinium enhancement. These techniques have the potential for registration accuracy to within a small fraction of a voxel or resolution element and therefore interpolation errors in image transformation can be the dominant source of error in subtracted images. We present a method for removing these errors using sinc interpolation and show how interpolation errors can be reduced by over two orders of magnitude.

  19. Rank Ordering or Judge-Awarded Ratings?

    ERIC Educational Resources Information Center

    Linacre, John M.

    Rank ordering examinees is an easier task for judges than is awarding numerical ratings. A measurement model for rankings based on Rasch's objectivity axioms provides linear, sample-independent and judge-independent measures. Estimates of examinee measures are obtained from the data set of rankings, along with standard errors and fit statistics.…

  20. Magnetic order in ?

    NASA Astrophysics Data System (ADS)

    Crook, M. R.; Coles, B. R.; Ritter, C.; Cywinski, R.

    1996-10-01

    Neutron powder diffraction has been used to study the evolution of magnetic order with increasing Zr substitution in the C14 Laves phase compounds 0953-8984/8/41/022/img8. For compounds with x = 0.3 and x = 0.4 we find a simple antiferromagnetic structure, similar to that reported for isostructural 0953-8984/8/41/022/img9. In this structure the Fe moments at the 6h sites are aligned along the c-axis, ferromagnetically coupled within the a - b plane, with adjacent planes antiferromagnetically coupled. This spin structure results in a cancellation of the molecular field at the interplanar 2a sites, and the Fe atoms at these sites carry no ordered moment. The neutron diffraction measurements on 0953-8984/8/41/022/img10 compounds in the composition range 0953-8984/8/41/022/img11 provide evidence of a low-temperature spin-canted structure in which the antiferromagnetic structure described above is modified by the appearance of a basal-plane ferromagnetic component which in turn leads to a small ordered Fe moment at the 2a site. The temperature dependence of the staggered magnetization in the antiferromagnetic state of the x = 0.4 compounds is found to closely follow the form 0953-8984/8/41/022/img12, as predicted for weak itinerant antiferromagnets by SCR spin-fluctuation theory.

  1. When is Chemical Similarity Significant? The Statistical Distribution of Chemical Similarity Scores and Its Extreme Values

    PubMed Central

    Baldi, Pierre

    2010-01-01

    As repositories of chemical molecules continue to expand and become more open, it becomes increasingly important to develop tools to search them efficiently and assess the statistical significance of chemical similarity scores. Here we develop a general framework for understanding, modeling, predicting, and approximating the distribution of chemical similarity scores and its extreme values in large databases. The framework can be applied to different chemical representations and similarity measures but is demonstrated here using the most common binary fingerprints with the Tanimoto similarity measure. After introducing several probabilistic models of fingerprints, including the Conditional Gaussian Uniform model, we show that the distribution of Tanimoto scores can be approximated by the distribution of the ratio of two correlated Normal random variables associated with the corresponding unions and intersections. This remains true also when the distribution of similarity scores is conditioned on the size of the query molecules in order to derive more fine-grained results and improve chemical retrieval. The corresponding extreme value distributions for the maximum scores are approximated by Weibull distributions. From these various distributions and their analytical forms, Z-scores, E-values, and p-values are derived to assess the significance of similarity scores. In addition, the framework allows one to predict also the value of standard chemical retrieval metrics, such as Sensitivity and Specificity at fixed thresholds, or ROC (Receiver Operating Characteristic) curves at multiple thresholds, and to detect outliers in the form of atypical molecules. Numerous and diverse experiments carried in part with large sets of molecules from the ChemDB show remarkable agreement between theory and empirical results. PMID:20540577

  2. Modeling Timbre Similarity of Short Music Clips

    PubMed Central

    Siedenburg, Kai; Müllensiefen, Daniel

    2017-01-01

    There is evidence from a number of recent studies that most listeners are able to extract information related to song identity, emotion, or genre from music excerpts with durations in the range of tenths of seconds. Because of these very short durations, timbre as a multifaceted auditory attribute appears as a plausible candidate for the type of features that listeners make use of when processing short music excerpts. However, the importance of timbre in listening tasks that involve short excerpts has not yet been demonstrated empirically. Hence, the goal of this study was to develop a method that allows to explore to what degree similarity judgments of short music clips can be modeled with low-level acoustic features related to timbre. We utilized the similarity data from two large samples of participants: Sample I was obtained via an online survey, used 16 clips of 400 ms length, and contained responses of 137,339 participants. Sample II was collected in a lab environment, used 16 clips of 800 ms length, and contained responses from 648 participants. Our model used two sets of audio features which included commonly used timbre descriptors and the well-known Mel-frequency cepstral coefficients as well as their temporal derivates. In order to predict pairwise similarities, the resulting distances between clips in terms of their audio features were used as predictor variables with partial least-squares regression. We found that a sparse selection of three to seven features from both descriptor sets—mainly encoding the coarse shape of the spectrum as well as spectrotemporal variability—best predicted similarities across the two sets of sounds. Notably, the inclusion of non-acoustic predictors of musical genre and record release date allowed much better generalization performance and explained up to 50% of shared variance (R2) between observations and model predictions. Overall, the results of this study empirically demonstrate that both acoustic features related

  3. Communications on quantum similarity, part 3: a geometric-quantum similarity molecular superposition algorithm.

    PubMed

    Carbó-Dorca, Ramon; Besalú, Emili; Mercado, Luz Dary

    2011-03-01

    This work describes a new procedure to obtain optimal molecular superposition based on quantum similarity (QS): the geometric-quantum similarity molecular superposition (GQSMS) algorithm. It has been inspired by the QS Aufbau principle, already described in a previous work, to build up coherently quantum similarity matrices (QSMs). The cornerstone of the present superposition technique relies upon the fact that quantum similarity integrals (QSIs), defined using a GTO basis set, depend on the squared intermolecular atomic distances. The resulting QSM structure, constructed under the GQSMS algorithm, becomes not only optimal in terms of its QSI elements but can also be arranged to produce a positive definite matrix global structure. Kruskal minimum spanning trees are also discussed as a device to order molecular sets described in turn by means of QSM. Besides the main subject of this work, focused on MS and QS, other practical considerations are also included in this study: essentially the use of elementary Jacobi rotations as QSM refinement tools and inward functions as QSM scaling methods. Copyright © 2010 Wiley Periodicals, Inc.

  4. Dependency Similarity, Attraction and Perceived Happiness.

    ERIC Educational Resources Information Center

    Pandey, Janak

    1978-01-01

    Subjects were asked to evaluate either a similar personality or a dissimilar personality. Subjects rated similar others more positively than dissimilar others and, additionally, perceived similar others as more helpful and sympathetic than dissimilar others. (Author)

  5. Protein Similarity Networks Reveal Relationships among Sequence, Structure, and Function within the Cupin Superfamily

    PubMed Central

    Uberto, Richard; Moomaw, Ellen W.

    2013-01-01

    The cupin superfamily is extremely diverse and includes catalytically inactive seed storage proteins, sugar-binding metal-independent epimerases, and metal-dependent enzymes possessing dioxygenase, decarboxylase, and other activities. Although numerous proteins of this superfamily have been structurally characterized, the functions of many of them have not been experimentally determined. We report the first use of protein similarity networks (PSNs) to visualize trends of sequence and structure in order to make functional inferences in this remarkably diverse superfamily. PSNs provide a way to visualize relatedness of structure and sequence among a given set of proteins. Structure- and sequence-based clustering of cupin members reflects functional clustering. Networks based only on cupin domains and networks based on the whole proteins provide complementary information. Domain-clustering supports phylogenetic conclusions that the N- and C-terminal domains of bicupin proteins evolved independently. Interestingly, although many functionally similar enzymatic cupin members bind the same active site metal ion, the structure and sequence clustering does not correlate with the identity of the bound metal. It is anticipated that the application of PSNs to this superfamily will inform experimental work and influence the functional annotation of databases. PMID:24040257

  6. Protein similarity networks reveal relationships among sequence, structure, and function within the Cupin superfamily.

    PubMed

    Uberto, Richard; Moomaw, Ellen W

    2013-01-01

    The cupin superfamily is extremely diverse and includes catalytically inactive seed storage proteins, sugar-binding metal-independent epimerases, and metal-dependent enzymes possessing dioxygenase, decarboxylase, and other activities. Although numerous proteins of this superfamily have been structurally characterized, the functions of many of them have not been experimentally determined. We report the first use of protein similarity networks (PSNs) to visualize trends of sequence and structure in order to make functional inferences in this remarkably diverse superfamily. PSNs provide a way to visualize relatedness of structure and sequence among a given set of proteins. Structure- and sequence-based clustering of cupin members reflects functional clustering. Networks based only on cupin domains and networks based on the whole proteins provide complementary information. Domain-clustering supports phylogenetic conclusions that the N- and C-terminal domains of bicupin proteins evolved independently. Interestingly, although many functionally similar enzymatic cupin members bind the same active site metal ion, the structure and sequence clustering does not correlate with the identity of the bound metal. It is anticipated that the application of PSNs to this superfamily will inform experimental work and influence the functional annotation of databases.

  7. Similarity Grouping and Repetition Blindness are Both Influenced by Attention

    PubMed Central

    de Haan, Bianca; Rorden, Chris

    2009-01-01

    Previous studies have reported seemingly conflicting results regarding how the amount of stimulus similarity between two simultaneously presented target stimuli impacts perceptual performance. There are many reports of ‘repetition blindness’, where individuals do worse when shown two similar stimuli relative to two different stimuli. On the other hand, there are reports of ‘similarity grouping’, where participants perform better when identifying two similar objects relative to two different objects. This manuscript posits that repetition blindness and similarity grouping coexist and can be elicited in the same subjects in a single task. This not only explains the previous opposite effects of stimulus similarity on task performance, but also provides a unique opportunity to directly compare these opposite effects of stimulus similarity with respect to susceptibility to a modulating factor. Since previous studies have provided inconclusive results on whether attentional relevance can modulate the effect of stimulus similarity on task performance, the current manuscript aims to compare repetition blindness and similarity grouping with respect to their susceptibility to attentional relevance. The results of the first experiment confirmed that both repetition blindness and similarity grouping can be elicited in the same experiment, suggesting that repetition blindness and similarity grouping coexist. The results of the second experiment suggest that both repetition blindness and similarity grouping can be modulated by attentional relevance. These results support the explanation of repetition blindness as a token individuation failure. Furthermore, these results suggest that supposedly pre-attentional grouping mechanisms might not operate as independently from top-down attentional modulations as traditionally thought. PMID:20300466

  8. 23. Historic American Buildings Survey. 'Fort Independence,' 1801, by John ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Historic American Buildings Survey. 'Fort Independence,' 1801, by John Foncin. French artillerist and military engineer and designer of Fort McHenry. This plan includes alternate arrangements for grouping of the inner buildings 'Fig. 2' being similar to Fort McHenry. - Fort McHenry National Monument & Historic Shrine, East Fort Avenue at Whetstone Point, Baltimore, Independent City, MD

  9. Optimal neighborhood indexing for protein similarity search.

    PubMed

    Peterlongo, Pierre; Noé, Laurent; Lavenier, Dominique; Nguyen, Van Hoa; Kucherov, Gregory; Giraud, Mathieu

    2008-12-16

    Similarity inference, one of the main bioinformatics tasks, has to face an exponential growth of the biological data. A classical approach used to cope with this data flow involves heuristics with large seed indexes. In order to speed up this technique, the index can be enhanced by storing additional information to limit the number of random memory accesses. However, this improvement leads to a larger index that may become a bottleneck. In the case of protein similarity search, we propose to decrease the index size by reducing the amino acid alphabet. The paper presents two main contributions. First, we show that an optimal neighborhood indexing combining an alphabet reduction and a longer neighborhood leads to a reduction of 35% of memory involved into the process, without sacrificing the quality of results nor the computational time. Second, our approach led us to develop a new kind of substitution score matrices and their associated e-value parameters. In contrast to usual matrices, these matrices are rectangular since they compare amino acid groups from different alphabets. We describe the method used for computing those matrices and we provide some typical examples that can be used in such comparisons. Supplementary data can be found on the website http://bioinfo.lifl.fr/reblosum. We propose a practical index size reduction of the neighborhood data, that does not negatively affect the performance of large-scale search in protein sequences. Such an index can be used in any study involving large protein data. Moreover, rectangular substitution score matrices and their associated statistical parameters can have applications in any study involving an alphabet reduction.

  10. Optimal neighborhood indexing for protein similarity search

    PubMed Central

    Peterlongo, Pierre; Noé, Laurent; Lavenier, Dominique; Nguyen, Van Hoa; Kucherov, Gregory; Giraud, Mathieu

    2008-01-01

    Background Similarity inference, one of the main bioinformatics tasks, has to face an exponential growth of the biological data. A classical approach used to cope with this data flow involves heuristics with large seed indexes. In order to speed up this technique, the index can be enhanced by storing additional information to limit the number of random memory accesses. However, this improvement leads to a larger index that may become a bottleneck. In the case of protein similarity search, we propose to decrease the index size by reducing the amino acid alphabet. Results The paper presents two main contributions. First, we show that an optimal neighborhood indexing combining an alphabet reduction and a longer neighborhood leads to a reduction of 35% of memory involved into the process, without sacrificing the quality of results nor the computational time. Second, our approach led us to develop a new kind of substitution score matrices and their associated e-value parameters. In contrast to usual matrices, these matrices are rectangular since they compare amino acid groups from different alphabets. We describe the method used for computing those matrices and we provide some typical examples that can be used in such comparisons. Supplementary data can be found on the website . Conclusion We propose a practical index size reduction of the neighborhood data, that does not negatively affect the performance of large-scale search in protein sequences. Such an index can be used in any study involving large protein data. Moreover, rectangular substitution score matrices and their associated statistical parameters can have applications in any study involving an alphabet reduction. PMID:19087280

  11. Stability of linear systems in second-order form based on structure preserving similarity transformations

    SciTech Connect

    Stoustrup, Jakob; Pommer, Christian; Kliem, Wolfhard

    2015-10-31

    This paper deals with two stability aspects of linear systems of the form I ¨ x +B˙ x +Cx = 0 given by the triple (I;B;C). A general transformation scheme is given for a structure and Jordan form preserving transformation of the triple. We investigate how a system can be transformed by suitable choices of the transformation parameters into a new system (I;B1;C1) with a symmetrizable matrix C1. This procedure facilitates stability investigations. We also consider systems with a Hamiltonian spectrum which discloses marginal stability after a Jordan form preserving transformation.

  12. Tachyon search speeds up retrieval of similar sequences by several orders of magnitude

    PubMed Central

    Tan, Joshua; Kuchibhatla, Durga; Sirota, Fernanda L.; Sherman, Westley A.; Gattermayer, Tobias; Kwoh, Chia Yee; Eisenhaber, Frank; Schneider, Georg; Maurer-Stroh, Sebastian

    2012-01-01

    Summary: The usage of current sequence search tools becomes increasingly slower as databases of protein sequences continue to grow exponentially. Tachyon, a new algorithm that identifies closely related protein sequences ~200 times faster than standard BLAST, circumvents this limitation with a reduced database and oligopeptide matching heuristic. Availability and implementation: The tool is publicly accessible as a webserver at http://tachyon.bii.a-star.edu.sg and can also be accessed programmatically through SOAP. Contact: sebastianms@bii.a-star.edu.sg Supplementary information: Supplementary data are available at the Bioinformatics online. PMID:22531216

  13. Beyond Literal Similarity. Technical Report No. 105.

    ERIC Educational Resources Information Center

    Ortony, Andrew

    Hitherto, theories of similarity have restricted themselves to judgments of what might be called literal similarity. A central thesis of this paper is that a complete account of similarity needs also to be sensitive to nonliteralness, or metaphoricity, an aspect of similarity statements that is most evident in similes, but that actually underlies…

  14. s-order nondiagonal quasiprobabilities

    NASA Astrophysics Data System (ADS)

    de Oliveira, Fernando A. M.

    1992-04-01

    This paper presents a correspondence between the annihilation a^ and creation a^° operators and two independent complex variables α and β, which makes possible the definition of positive nondiagonal quasiprobabilities for any Cahill-Glauber s order. A generalized version of the Cahill and Glauber s-ordered displacement operator displacing the annihilation and creation operators by α and β is defined. Corresponding to this n/Inondiagonal displacement, a nondiagonal ordering operator is introduced so that a map of s-ordered operators into c numbers a^-->α, a^°-->β can be defined. The Drummond-Gardiner projector and the Cahill-Glauber diagonal ordering operator are obtained as particular cases. In order to use the nondiagonal correspondence in the determination of quantum expectation values of observables, several families of quasiprobabilities are defined, generalizing Drummond-Gardiner (normal order and nondiagonal) positive-P-function and Cahill-Glauber (s-order and diagonal) quasiprobabilities. It is demonstrated that these nondiagonal quasiprobabilities exist as well-behaved functions where at least one is non-negative, for any state and any order. The time evolution of these quasiprobabilities is discussed both in the Schrödinger and in the Heisenberg pictures. In the Heisenberg picture, a method for obtaining c-number stochastic differential equations (SDE's) directly from operator equations using the s-order nondiagonal correspondence is described. The main difference between this method and the Langevin approach is that in the latter a diagonal correspondence is used, leading eventually to wrong results. The use of these SDE's to solve quantum optical problems is discussed, and an application to the nonlinearly damped degenerate parametric oscillator is made. In order to obtain the SDE, various (inequivalent) truncation schemes are necessary.

  15. DDE Transposases: Structural Similarity and Diversity

    PubMed Central

    Nesmelova, Irina V.; Hackett, Perry B.

    2010-01-01

    DNA transposons are mobile DNA elements that can move from one DNA molecule to another and thereby deliver genetic information into human chromosomes in order to confer a new function or replace a defective gene. This process requires a transposase enzyme. During transposition DD[E/D]-transposases undergo a series of conformational changes. We summarize the structural features of DD[E/D]-transposases for which three-dimensional structures are available and that relate to transposases, which are being developed for use in mammalian cells. Similar to other members of the polynucleotidyl transferase family, the catalytic domains of DD[E/D]-transposases share a common feature: an RNase H-like fold that draws three catalytically active residues, the DDE motif, into close proximity. Beyond this fold, the structures of catalytic domains vary considerably, and the DD[E/D]-transposases display marked structural diversity within their DNA-binding domains. Yet despite such structural variability, essentially the same end result is achieved. PMID:20615441

  16. Order, chaos and nuclear dynamics: An introduction

    SciTech Connect

    Swiatecki, W.J.

    1990-08-01

    This is an introductory lecture illustrating by simple examples the anticipated effect on collective nuclear dynamics of a transition from order to chaos in the motions of nucleons inside an idealized nucleus. The destruction of order is paralleled by a transition from a rubber-like to a honey-like behaviour of the independent-particle nuclear model. 10 refs., 6 figs.

  17. A Study of Presidents of Independent Colleges and Universities

    ERIC Educational Resources Information Center

    Song, Wei; Hartley, Harold V., III

    2012-01-01

    The Council of Independent Colleges (CIC), a national association representing 640 small and mid-sized independent colleges and universities, supports many professional development programs for higher education leaders. Beginning in 2008 the design of the programs has been informed by research on the career paths of campus leaders in order to help…

  18. Visual similarity effects in categorical search.

    PubMed

    Alexander, Robert G; Zelinsky, Gregory J

    2011-07-14

    We asked how visual similarity relationships affect search guidance to categorically defined targets (no visual preview). Experiment 1 used a web-based task to collect visual similarity rankings between two target categories, teddy bears and butterflies, and random-category objects, from which we created search displays in Experiment 2 having either high-similarity distractors, low-similarity distractors, or "mixed" displays with high-, medium-, and low-similarity distractors. Analysis of target-absent trials revealed faster manual responses and fewer fixated distractors on low-similarity displays compared to high-similarity displays. On mixed displays, first fixations were more frequent on high-similarity distractors (bear = 49%; butterfly = 58%) than on low-similarity distractors (bear = 9%; butterfly = 12%). Experiment 3 used the same high/low/mixed conditions, but now these conditions were created using similarity estimates from a computer vision model that ranked objects in terms of color, texture, and shape similarity. The same patterns were found, suggesting that categorical search can indeed be guided by purely visual similarity. Experiment 4 compared cases where the model and human rankings differed and when they agreed. We found that similarity effects were best predicted by cases where the two sets of rankings agreed, suggesting that both human visual similarity rankings and the computer vision model captured features important for guiding search to categorical targets.

  19. Time ordering in atomic collisions

    NASA Astrophysics Data System (ADS)

    McGuire, J. H.; Godunov, A. L.; Shakov, Kh Kh; Kaplan, L.; Burin, A.; Uskov, D.

    2007-06-01

    Time ordering constrains interactions to occur in increasing (or decreasing) order. This places a constraint on the time evolution of the system and can lead to correlations in time of different particles in a few/many body system. Unlike overall time reversal, time ordering is not a conserved symmetry of the atomic system. A number of examples of observable effects of time ordering are presented. A convenient way to describe time ordering is to define the limit of no time ordering by replacing the instantaneous interaction by its time average. This is similar to the way in which spatial correlation is defined. Like spatial correlation, time ordering is usually formulated in the interaction representation. The effects of time ordering can differ in different representations. In energy space, conjugate to time space, time ordering is imposed as the i ɛ term in the Greens' function that corresponds to an initial condition (usually incoming plane waves and outgoing scattered waves). This permits off-energy-shell (energy non- conserving) fluctuations during the collision consistent with the Uncertainty Principle.

  20. Reconstructing propagation networks with temporal similarity

    PubMed Central

    Liao, Hao; Zeng, An

    2015-01-01

    Node similarity significantly contributes to the growth of real networks. In this paper, based on the observed epidemic spreading results we apply the node similarity metrics to reconstruct the underlying networks hosting the propagation. We find that the reconstruction accuracy of the similarity metrics is strongly influenced by the infection rate of the spreading process. Moreover, there is a range of infection rate in which the reconstruction accuracy of some similarity metrics drops nearly to zero. To improve the similarity-based reconstruction method, we propose a temporal similarity metric which takes into account the time information of the spreading. The reconstruction results are remarkably improved with the new method. PMID:26086198

  1. Reconstructing propagation networks with temporal similarity.

    PubMed

    Liao, Hao; Zeng, An

    2015-06-18

    Node similarity significantly contributes to the growth of real networks. In this paper, based on the observed epidemic spreading results we apply the node similarity metrics to reconstruct the underlying networks hosting the propagation. We find that the reconstruction accuracy of the similarity metrics is strongly influenced by the infection rate of the spreading process. Moreover, there is a range of infection rate in which the reconstruction accuracy of some similarity metrics drops nearly to zero. To improve the similarity-based reconstruction method, we propose a temporal similarity metric which takes into account the time information of the spreading. The reconstruction results are remarkably improved with the new method.

  2. Characteristics associated with organizational independence in consumer-operated service organizations.

    PubMed

    Tanenbaum, Sandra J

    2011-01-01

    This research compares two types of consumer organizations in one state in order to explore the significance of organizational independence for internal structure/operations and external relationships. The first type, consumeroperated service organizations (COSOs), are independent and fully self-governing; the second are peer-support service organizations (PSSOs), which are part of larger non-consumer entities. Mail surveys were completed by COSO and PSSO directors of a geographically representative sample of organizations; telephone interviews were conducted with a sub-sample. Owing to small sample size, matched COSO-PSSO pairs were analyzed using non-parametric statistics. COSOs and PSSOs are similar in some ways, e.g., types of services provided, but significantly different on internal variables, such as budget size, and external variables, such as number of relationships with community groups. Organizational independence appears to be a significant characteristic for consumer service organizations and should be encouraged by funders and among participants. Funders might establish administrative and/or programmatic measures to support consumer organizations that are independent or moving toward independence; their participants would also benefit from the provision, by authorities or advocates, of materials to guide organizations toward, for example, 501(c)3 status.

  3. A Distance and Angle Similarity Measure Method.

    ERIC Educational Resources Information Center

    Zhang, Jin; Korfhage, Robert R.

    1999-01-01

    Discusses similarity measures that are used in information retrieval to improve precision and recall ratios and presents a combined vector-based distance and angle measure to make similarity measurement more scientific and accurate. Suggests directions for future research. (LRW)

  4. Quantifying similarity of pore-geometry in nanoporous materials.

    PubMed

    Lee, Yongjin; Barthel, Senja D; Dłotko, Paweł; Moosavi, S Mohamad; Hess, Kathryn; Smit, Berend

    2017-05-23

    In most applications of nanoporous materials the pore structure is as important as the chemical composition as a determinant of performance. For example, one can alter performance in applications like carbon capture or methane storage by orders of magnitude by only modifying the pore structure. For these applications it is therefore important to identify the optimal pore geometry and use this information to find similar materials. However, the mathematical language and tools to identify materials with similar pore structures, but different composition, has been lacking. We develop a pore recognition approach to quantify similarity of pore structures and classify them using topological data analysis. This allows us to identify materials with similar pore geometries, and to screen for materials that are similar to given top-performing structures. Using methane storage as a case study, we also show that materials can be divided into topologically distinct classes requiring different optimization strategies.

  5. Quantifying similarity of pore-geometry in nanoporous materials

    NASA Astrophysics Data System (ADS)

    Lee, Yongjin; Barthel, Senja D.; Dłotko, Paweł; Moosavi, S. Mohamad; Hess, Kathryn; Smit, Berend

    2017-05-01

    In most applications of nanoporous materials the pore structure is as important as the chemical composition as a determinant of performance. For example, one can alter performance in applications like carbon capture or methane storage by orders of magnitude by only modifying the pore structure. For these applications it is therefore important to identify the optimal pore geometry and use this information to find similar materials. However, the mathematical language and tools to identify materials with similar pore structures, but different composition, has been lacking. We develop a pore recognition approach to quantify similarity of pore structures and classify them using topological data analysis. This allows us to identify materials with similar pore geometries, and to screen for materials that are similar to given top-performing structures. Using methane storage as a case study, we also show that materials can be divided into topologically distinct classes requiring different optimization strategies.

  6. Exact Score Distribution Computation for Similarity Searches in Ontologies

    NASA Astrophysics Data System (ADS)

    Schulz, Marcel H.; Köhler, Sebastian; Bauer, Sebastian; Vingron, Martin; Robinson, Peter N.

    Semantic similarity searches in ontologies are an important component of many bioinformatic algorithms, e.g., protein function prediction with the Gene Ontology. In this paper we consider the exact computation of score distributions for similarity searches in ontologies, and introduce a simple null hypothesis which can be used to compute a P-value for the statistical significance of similarity scores. We concentrate on measures based on Resnik’s definition of ontological similarity. A new algorithm is proposed that collapses subgraphs of the ontology graph and thereby allows fast score distribution computation. The new algorithm is several orders of magnitude faster than the naive approach, as we demonstrate by computing score distributions for similarity searches in the Human Phenotype Ontology.

  7. Quantifying similarity of pore-geometry in nanoporous materials

    DOE PAGES

    Lee, Yongjin; Barthel, Senja D.; Dłotko, Paweł; ...

    2017-05-23

    In most applications of nanoporous materials the pore structure is as important as the chemical composition as a determinant of performance. For example, one can alter performance in applications like carbon capture or methane storage by orders of magnitude by only modifying the pore structure. For these applications it is therefore important to identify the optimal pore geometry and use this information to find similar materials. But, the mathematical language and tools to identify materials with similar pore structures, but different composition, has been lacking. We develop a pore recognition approach to quantify similarity of pore structures and classify themmore » using topological data analysis. This then allows us to identify materials with similar pore geometries, and to screen for materials that are similar to given top-performing structures. Using methane storage as a case study, we also show that materials can be divided into topologically distinct classes requiring different optimization strategies.« less

  8. Constructing lncRNA functional similarity network based on lncRNA-disease associations and disease semantic similarity.

    PubMed

    Chen, Xing; Yan, Chenggang Clarence; Luo, Cai; Ji, Wen; Zhang, Yongdong; Dai, Qionghai

    2015-06-10

    Increasing evidence has indicated that plenty of lncRNAs play important roles in many critical biological processes. Developing powerful computational models to construct lncRNA functional similarity network based on heterogeneous biological datasets is one of the most important and popular topics in the fields of both lncRNAs and complex diseases. Functional similarity network construction could benefit the model development for both lncRNA function inference and lncRNA-disease association identification. However, little effort has been attempted to analysis and calculate lncRNA functional similarity on a large scale. In this study, based on the assumption that functionally similar lncRNAs tend to be associated with similar diseases, we developed two novel lncRNA functional similarity calculation models (LNCSIM). LNCSIM was evaluated by introducing similarity scores into the model of Laplacian Regularized Least Squares for LncRNA-Disease Association (LRLSLDA) for lncRNA-disease association prediction. As a result, new predictive models improved the performance of LRLSLDA in the leave-one-out cross validation of various known lncRNA-disease associations datasets. Furthermore, some of the predictive results for colorectal cancer and lung cancer were verified by independent biological experimental studies. It is anticipated that LNCSIM could be a useful and important biological tool for human disease diagnosis, treatment, and prevention.

  9. Asteroid clusters similar to asteroid pairs

    NASA Astrophysics Data System (ADS)

    Pravec, Petr; Vokrouhlicky, David; Fatka, Petr; Kusnirák, Peter; Hornoch, Kamil; Galád, Adrián

    2016-10-01

    We study five small, tight and young clusters of asteroids. They are placed around following largest (primary) bodies: (11842) Kap'bos, (14627) Emilkowalski, (16598) 1992 YC2, (21509) Lucascavin and (39991) 1998 HR37. Each cluster has 2-4 secondaries that are tightly clustered around the primary body, with distance in the 5-dimensional space of mean orbital elements mostly within 10 m/s, and always < 23 m/s. Backward orbital integrations indicate that they formed between 105 and 106 yr ago. In the P1-q space, where P1 is the primary's spin period and q = Σ Mj/M1 is the total secondary-to-primary mass ratio, the clusters lie in the same range as asteroid pairs formed by rotational fission. We have extended the model of a proto-system separation after rotational fission by Pravec et al. (2010) for application to systems with more than one secondary and found a perfect match for the five tight clusters. We find these clusters to be similar to asteroid pairs and we suggest that they are "extended pairs", having 2-4 escaped secondaries rather than just one secondary as in the case of an asteroid pair. We compare them to six young mini-families (1270) Datura, (2384) Schulhof, (3152) Jones, (6825) Irvine, (10321) Rampo and (20674) 1999 VT1. These mini-families have similar ages, but they have a higher number of members and/or they show a significantly larger spread in the mean orbital elements (dmean on an order of tens m/s) than the five tight clusters. In the P1-q space, all but one of the mini-families lie in the same range as asteroid pairs and the tight clusters; the exception is the mini-family of (3152) Jones which appears to be a collisional family. A possibility that the other five mini-families were also formed by rotational fission as we suggest for the tight clusters ("extended asteroid pairs") is being explored.Reference:Pravec, P., et al. Formation of asteroid pairs by rotational fission. Nature 466, 1085-1088.

  10. Independent Learning Models: A Comparison.

    ERIC Educational Resources Information Center

    Wickett, R. E. Y.

    Five models of independent learning are suitable for use in adult education programs. The common factor is a facilitator who works in some way with the student in the learning process. They display different characteristics, including the extent of independence in relation to content and/or process. Nondirective tutorial instruction and learning…

  11. Marketing Handbook for Independent Schools.

    ERIC Educational Resources Information Center

    Boarding Schools, Boston, MA.

    This publication is a resource to help independent schools attract more familites to their institutions and to increase the voluntary support by the larger community surrounding the school. The first chapter attempts to dispel misconceptions, define pertinent marketing terms, and relate their importance to independent schools. The rest of the book…

  12. Thematic Relations Affect Similarity via Commonalities

    ERIC Educational Resources Information Center

    Golonka, Sabrina; Estes, Zachary

    2009-01-01

    Thematic relations are an important source of perceived similarity. For instance, the "rowing" theme of boats and oars increases their perceived similarity. The mechanism of this effect, however, has not been specified previously. The authors investigated whether thematic relations affect similarity by increasing commonalities or by…

  13. Thematic Relations Affect Similarity via Commonalities

    ERIC Educational Resources Information Center

    Golonka, Sabrina; Estes, Zachary

    2009-01-01

    Thematic relations are an important source of perceived similarity. For instance, the "rowing" theme of boats and oars increases their perceived similarity. The mechanism of this effect, however, has not been specified previously. The authors investigated whether thematic relations affect similarity by increasing commonalities or by…

  14. Manipulation of pure spin current in ferromagnetic metals independent of magnetization

    NASA Astrophysics Data System (ADS)

    Tian, Dai; Li, Yufan; Qu, D.; Huang, S. Y.; Jin, Xiaofeng; Chien, C. L.

    2016-07-01

    Upon the injection of a pure spin current, a ferromagnet, similar to a nonmagnetic metal, also exhibits inverse spin Hall effect (ISHE). We show in Co/Cu/YIG, where the thin Cu layer allows transmission of spin current from YIG into Co but decouples the two ferromagnets, that the interaction between ISHE and ferromagnetic ordering in Co can be unambiguously investigated. By switching on and off the pure spin current contribution, we demonstrate that the ISHE in Co is independent of the direction of the Co magnetization, which clearly suggests that the ISHE in Co is dominated not by the extrinsic impurity scatterings, but from the intrinsic origin.

  15. Independent molecular basis of convergent highland adaptation in maize

    USDA-ARS?s Scientific Manuscript database

    Convergent evolution is the independent evolution of similar traits in different species or lineages of the same species; this often is a result of adaptation to similar environments, a process referred to as convergent adaptation. We investigate here the molecular basis of convergent adaptation in ...

  16. Structure Modulates Similarity-Based Interference in Sluicing: An Eye Tracking study

    PubMed Central

    Harris, Jesse A.

    2015-01-01

    In cue-based content-addressable approaches to memory, a target and its competitors are retrieved in parallel from memory via a fast, associative cue-matching procedure under a severely limited focus of attention. Such a parallel matching procedure could in principle ignore the serial order or hierarchical structure characteristic of linguistic relations. I present an eye tracking while reading experiment that investigates whether the sentential position of a potential antecedent modulates the strength of similarity-based interference, a well-studied effect in which increased similarity in features between a target and its competitors results in slower and less accurate retrieval overall. The manipulation trades on an independently established Locality bias in sluiced structures to associate a wh-remnant (which ones) in clausal ellipsis with the most local correlate (some wines), as in The tourists enjoyed some wines, but I don't know which ones. The findings generally support cue-based parsing models of sentence processing that are subject to similarity-based interference in retrieval, and provide additional support to the growing body of evidence that retrieval is sensitive to both the structural position of a target antecedent and its competitors, and the specificity or diagnosticity of retrieval cues. PMID:26733893

  17. A toolbox for representational similarity analysis.

    PubMed

    Nili, Hamed; Wingfield, Cai; Walther, Alexander; Su, Li; Marslen-Wilson, William; Kriegeskorte, Nikolaus

    2014-04-01

    Neuronal population codes are increasingly being investigated with multivariate pattern-information analyses. A key challenge is to use measured brain-activity patterns to test computational models of brain information processing. One approach to this problem is representational similarity analysis (RSA), which characterizes a representation in a brain or computational model by the distance matrix of the response patterns elicited by a set of stimuli. The representational distance matrix encapsulates what distinctions between stimuli are emphasized and what distinctions are de-emphasized in the representation. A model is tested by comparing the representational distance matrix it predicts to that of a measured brain region. RSA also enables us to compare representations between stages of processing within a given brain or model, between brain and behavioral data, and between individuals and species. Here, we introduce a Matlab toolbox for RSA. The toolbox supports an analysis approach that is simultaneously data- and hypothesis-driven. It is designed to help integrate a wide range of computational models into the analysis of multichannel brain-activity measurements as provided by modern functional imaging and neuronal recording techniques. Tools for visualization and inference enable the user to relate sets of models to sets of brain regions and to statistically test and compare the models using nonparametric inference methods. The toolbox supports searchlight-based RSA, to continuously map a measured brain volume in search of a neuronal population code with a specific geometry. Finally, we introduce the linear-discriminant t value as a measure of representational discriminability that bridges the gap between linear decoding analyses and RSA. In order to demonstrate the capabilities of the toolbox, we apply it to both simulated and real fMRI data. The key functions are equally applicable to other modalities of brain-activity measurement. The toolbox is freely

  18. Humans and Insects Decide in Similar Ways

    PubMed Central

    Louâpre, Philippe; van Alphen, Jacques J. M.; Pierre, Jean-Sébastien

    2010-01-01

    Behavioral ecologists assume that animals use a motivational mechanism for decisions such as action selection and time allocation, allowing the maximization of their fitness. They consider both the proximate and ultimate causes of behavior in order to understand this type of decision-making in animals. Experimental psychologists and neuroeconomists also study how agents make decisions but they consider the proximate causes of the behavior. In the case of patch-leaving, motivation-based decision-making remains simple speculation. In contrast to other animals, human beings can assess and evaluate their own motivation by an introspection process. It is then possible to study the declared motivation of humans during decision-making and discuss the mechanism used as well as its evolutionary significance. In this study, we combine both the proximate and ultimate causes of behavior for a better understanding of the human decision-making process. We show for the first time ever that human subjects use a motivational mechanism similar to small insects such as parasitoids [1] and bumblebees [2] to decide when to leave a patch. This result is relevant for behavioral ecologists as it supports the biological realism of this mechanism. Humans seem to use a motivational mechanism of decision making known to be adaptive to a heterogeneously distributed resource. As hypothesized by Hutchinson et al. [3] and Wilke and Todd [4], our results are consistent with the evolutionary shaping of decision making because hominoids were hunters and gatherers on food patches for more than two million years. We discuss the plausibility of a neural basis for the motivation mechanism highlighted here, bridging the gap between behavioral ecology and neuroeconomy. Thus, both the motivational mechanism observed here and the neuroeconomy findings are most likely adaptations that were selected for during ancestral times. PMID:21170378

  19. A genetic similarity rule determines arthropod community structure.

    PubMed

    Bangert, R K; Turek, R J; Rehill, B; Wimp, G M; Schweitzer, J A; Allan, G J; Bailey, J K; Martinsen, G D; Keim, P; Lindroth, R L; Whitham, T G

    2006-04-01

    We define a genetic similarity rule that predicts how genetic variation in a dominant plant affects the structure of an arthropod community. This rule applies to hybridizing cottonwood species where plant genetic variation determines plant-animal interactions and structures a dependent community of leaf-modifying arthropods. Because the associated arthropod community is expected to respond to important plant traits, we also tested whether plant chemical composition is one potential intermediate link between plant genes and arthropod community composition. Two lines of evidence support our genetic similarity rule. First, in a common garden experiment we found that trees with similar genetic compositions had similar chemical compositions and similar arthropod compositions. Second, in a wild population, we found a similar relationship between genetic similarity in cottonwoods and the dependent arthropod community. Field data demonstrate that the relationship between genes and arthropods was also significant when the hybrids were analysed alone, i.e. the pattern is not dependent upon the inclusion of both parental species. Because plant-animal interactions and natural hybridization are common to diverse plant taxa, we suggest that a genetic similarity rule is potentially applicable, and may be extended, to other systems and ecological processes. For example, plants with similar genetic compositions may exhibit similar litter decomposition rates. A corollary to this genetic similarity rule predicts that in systems with low plant genetic variability, the environment will be a stronger factor structuring the dependent community. Our findings argue that the genetic composition of a dominant plant can structure higher order ecological processes, thus placing community and ecosystem ecology within a genetic and evolutionary framework. A genetic similarity rule also has important conservation implications because the loss of genetic diversity in one species, especially

  20. Testing the Role of Semantic Similarity in Syntactic Development

    ERIC Educational Resources Information Center

    Ninio, Anat

    2005-01-01

    The study explored early syntactic development, and tested the hypothesis that children use similarity of meaning in order to move beyond the learning of individual item-based multiword constructions. The first 6 types of verb-object (VO) constructions in Hebrew-speaking children were analysed for the occurrence of transfer of learning and…

  1. Chromatic induction and contrast masking: similar models, different goals?

    NASA Astrophysics Data System (ADS)

    Jiménez, Sandra; Otazu, Xavier; Laparra, Valero; Malo, Jesús

    2013-03-01

    Normalization of signals coming from linear sensors is an ubiquitous mechanism of neural adaptation.1 Local interaction between sensors tuned to a particular feature at certain spatial position and neighbor sensors explains a wide range of psychophysical facts including (1) masking of spatial patterns, (2) non-linearities of motion sensors, (3) adaptation of color perception, (4) brightness and chromatic induction, and (5) image quality assessment. Although the above models have formal and qualitative similarities, it does not necessarily mean that the mechanisms involved are pursuing the same statistical goal. For instance, in the case of chromatic mechanisms (disregarding spatial information), different parameters in the normalization give rise to optimal discrimination or adaptation, and different non-linearities may give rise to error minimization or component independence. In the case of spatial sensors (disregarding color information), a number of studies have pointed out the benefits of masking in statistical independence terms. However, such statistical analysis has not been performed for spatio-chromatic induction models where chromatic perception depends on spatial configuration. In this work we investigate whether successful spatio-chromatic induction models,6 increase component independence similarly as previously reported for masking models. Mutual information analysis suggests that seeking an efficient chromatic representation may explain the prevalence of induction effects in spatially simple images.

  2. Complex Quasi-Two-Dimensional Crystalline Order Embedded in VO2 and Other Crystals

    NASA Astrophysics Data System (ADS)

    Lovorn, Timothy; Sarker, Sanjoy K.

    2017-07-01

    Metal oxides such as VO2 undergo structural transitions to low-symmetry phases characterized by intricate crystalline order, accompanied by rich electronic behavior. We derive a minimal ionic Hamiltonian based on symmetry and local energetics which describes structural transitions involving all four observed phases, in the correct order. An exact analysis shows that complexity results from the symmetry-induced constraints of the parent phase, which forces ionic displacements to form multiple interpenetrating groups using low-dimensional pathways and distant neighbors. Displacements within each group exhibit independent, quasi-two-dimensional order, which is frustrated and fragile. This selective ordering mechanism is not restricted to VO2 : it applies to other oxides that show similar complex order.

  3. Rude awakening. [overseas development of independent power

    SciTech Connect

    Goodwin, L.M. )

    1993-07-15

    Developers will find language isn't the only thing that's different overseas. The nation's dramatic success in allowing competition in electric power generation and the subsequent growth in non-utility power plant development has encouraged other countries to try their hand at stimulating growth in their internal electric markets. This has coincided with a general trend toward privatizing what were once governmental functions, a process encouraged by international agencies such as the World Bank. Because U.S. developers have acquired significant experience developing independent power projects during the 15 years since the Public Utility Regulatory Policies Act (PURPA) was passed, they have been among the most aggressive participants in the early stages of international independent power development. Developers who try to transplant their domestic experience directly to foreign markets may be in for a rude awakening, however. Despite apparent similarities, significant differences exist between energy project development here and in international markets.

  4. Transition-Independent Decentralized Markov Decision Processes

    NASA Technical Reports Server (NTRS)

    Becker, Raphen; Silberstein, Shlomo; Lesser, Victor; Goldman, Claudia V.; Morris, Robert (Technical Monitor)

    2003-01-01

    There has been substantial progress with formal models for sequential decision making by individual agents using the Markov decision process (MDP). However, similar treatment of multi-agent systems is lacking. A recent complexity result, showing that solving decentralized MDPs is NEXP-hard, provides a partial explanation. To overcome this complexity barrier, we identify a general class of transition-independent decentralized MDPs that is widely applicable. The class consists of independent collaborating agents that are tied up by a global reward function that depends on both of their histories. We present a novel algorithm for solving this class of problems and examine its properties. The result is the first effective technique to solve optimally a class of decentralized MDPs. This lays the foundation for further work in this area on both exact and approximate solutions.

  5. Boosting medical diagnostics by pooling independent judgments

    PubMed Central

    Kurvers, Ralf H. J. M.; Herzog, Stefan M.; Hertwig, Ralph; Krause, Jens; Carney, Patricia A.; Bogart, Andy; Argenziano, Giuseppe; Zalaudek, Iris; Wolf, Max

    2016-01-01

    Collective intelligence refers to the ability of groups to outperform individual decision makers when solving complex cognitive problems. Despite its potential to revolutionize decision making in a wide range of domains, including medical, economic, and political decision making, at present, little is known about the conditions underlying collective intelligence in real-world contexts. We here focus on two key areas of medical diagnostics, breast and skin cancer detection. Using a simulation study that draws on large real-world datasets, involving more than 140 doctors making more than 20,000 diagnoses, we investigate when combining the independent judgments of multiple doctors outperforms the best doctor in a group. We find that similarity in diagnostic accuracy is a key condition for collective intelligence: Aggregating the independent judgments of doctors outperforms the best doctor in a group whenever the diagnostic accuracy of doctors is relatively similar, but not when doctors’ diagnostic accuracy differs too much. This intriguingly simple result is highly robust and holds across different group sizes, performance levels of the best doctor, and collective intelligence rules. The enabling role of similarity, in turn, is explained by its systematic effects on the number of correct and incorrect decisions of the best doctor that are overruled by the collective. By identifying a key factor underlying collective intelligence in two important real-world contexts, our findings pave the way for innovative and more effective approaches to complex real-world decision making, and to the scientific analyses of those approaches. PMID:27432950

  6. Noncontiguous atom matching structural similarity function.

    PubMed

    Teixeira, Ana L; Falcao, Andre O

    2013-10-28

    Measuring similarity between molecules is a fundamental problem in cheminformatics. Given that similar molecules tend to have similar physical, chemical, and biological properties, the notion of molecular similarity plays an important role in the exploration of molecular data sets, query-retrieval in molecular databases, and in structure-property/activity modeling. Various methods to define structural similarity between molecules are available in the literature, but so far none has been used with consistent and reliable results for all situations. We propose a new similarity method based on atom alignment for the analysis of structural similarity between molecules. This method is based on the comparison of the bonding profiles of atoms on comparable molecules, including features that are seldom found in other structural or graph matching approaches like chirality or double bond stereoisomerism. The similarity measure is then defined on the annotated molecular graph, based on an iterative directed graph similarity procedure and optimal atom alignment between atoms using a pairwise matching algorithm. With the proposed approach the similarities detected are more intuitively understood because similar atoms in the molecules are explicitly shown. This noncontiguous atom matching structural similarity method (NAMS) was tested and compared with one of the most widely used similarity methods (fingerprint-based similarity) using three difficult data sets with different characteristics. Despite having a higher computational cost, the method performed well being able to distinguish either different or very similar hydrocarbons that were indistinguishable using a fingerprint-based approach. NAMS also verified the similarity principle using a data set of structurally similar steroids with differences in the binding affinity to the corticosteroid binding globulin receptor by showing that pairs of steroids with a high degree of similarity (>80%) tend to have smaller differences

  7. From Sensory Signals to Modality-Independent Conceptual Representations: A Probabilistic Language of Thought Approach

    PubMed Central

    Erdogan, Goker; Yildirim, Ilker; Jacobs, Robert A.

    2015-01-01

    People learn modality-independent, conceptual representations from modality-specific sensory signals. Here, we hypothesize that any system that accomplishes this feat will include three components: a representational language for characterizing modality-independent representations, a set of sensory-specific forward models for mapping from modality-independent representations to sensory signals, and an inference algorithm for inverting forward models—that is, an algorithm for using sensory signals to infer modality-independent representations. To evaluate this hypothesis, we instantiate it in the form of a computational model that learns object shape representations from visual and/or haptic signals. The model uses a probabilistic grammar to characterize modality-independent representations of object shape, uses a computer graphics toolkit and a human hand simulator to map from object representations to visual and haptic features, respectively, and uses a Bayesian inference algorithm to infer modality-independent object representations from visual and/or haptic signals. Simulation results show that the model infers identical object representations when an object is viewed, grasped, or both. That is, the model’s percepts are modality invariant. We also report the results of an experiment in which different subjects rated the similarity of pairs of objects in different sensory conditions, and show that the model provides a very accurate account of subjects’ ratings. Conceptually, this research significantly contributes to our understanding of modality invariance, an important type of perceptual constancy, by demonstrating how modality-independent representations can be acquired and used. Methodologically, it provides an important contribution to cognitive modeling, particularly an emerging probabilistic language-of-thought approach, by showing how symbolic and statistical approaches can be combined in order to understand aspects of human perception. PMID

  8. From Sensory Signals to Modality-Independent Conceptual Representations: A Probabilistic Language of Thought Approach.

    PubMed

    Erdogan, Goker; Yildirim, Ilker; Jacobs, Robert A

    2015-11-01

    People learn modality-independent, conceptual representations from modality-specific sensory signals. Here, we hypothesize that any system that accomplishes this feat will include three components: a representational language for characterizing modality-independent representations, a set of sensory-specific forward models for mapping from modality-independent representations to sensory signals, and an inference algorithm for inverting forward models-that is, an algorithm for using sensory signals to infer modality-independent representations. To evaluate this hypothesis, we instantiate it in the form of a computational model that learns object shape representations from visual and/or haptic signals. The model uses a probabilistic grammar to characterize modality-independent representations of object shape, uses a computer graphics toolkit and a human hand simulator to map from object representations to visual and haptic features, respectively, and uses a Bayesian inference algorithm to infer modality-independent object representations from visual and/or haptic signals. Simulation results show that the model infers identical object representations when an object is viewed, grasped, or both. That is, the model's percepts are modality invariant. We also report the results of an experiment in which different subjects rated the similarity of pairs of objects in different sensory conditions, and show that the model provides a very accurate account of subjects' ratings. Conceptually, this research significantly contributes to our understanding of modality invariance, an important type of perceptual constancy, by demonstrating how modality-independent representations can be acquired and used. Methodologically, it provides an important contribution to cognitive modeling, particularly an emerging probabilistic language-of-thought approach, by showing how symbolic and statistical approaches can be combined in order to understand aspects of human perception.

  9. Independent component analysis for automatic note extraction from musical trills

    NASA Astrophysics Data System (ADS)

    Brown, Judith C.; Smaragdis, Paris

    2004-05-01

    The method of principal component analysis, which is based on second-order statistics (or linear independence), has long been used for redundancy reduction of audio data. The more recent technique of independent component analysis, enforcing much stricter statistical criteria based on higher-order statistical independence, is introduced and shown to be far superior in separating independent musical sources. This theory has been applied to piano trills and a database of trill rates was assembled from experiments with a computer-driven piano, recordings of a professional pianist, and commercially available compact disks. The method of independent component analysis has thus been shown to be an outstanding, effective means of automatically extracting interesting musical information from a sea of redundant data.

  10. Independent component analysis for automatic note extraction from musical trills.

    PubMed

    Brown, Judith C; Smaragdis, Paris

    2004-05-01

    The method of principal component analysis, which is based on second-order statistics (or linear independence), has long been used for redundancy reduction of audio data. The more recent technique of independent component analysis, enforcing much stricter statistical criteria based on higher-order statistical independence, is introduced and shown to be far superior in separating independent musical sources. This theory has been applied to piano trills and a database of trill rates was assembled from experiments with a computer-driven piano, recordings of a professional pianist, and commercially available compact disks. The method of independent component analysis has thus been shown to be an outstanding, effective means of automatically extracting interesting musical information from a sea of redundant data.

  11. Chandra Independently Determines Hubble Constant

    NASA Astrophysics Data System (ADS)

    2006-08-01

    A critically important number that specifies the expansion rate of the Universe, the so-called Hubble constant, has been independently determined using NASA's Chandra X-ray Observatory. This new value matches recent measurements using other methods and extends their validity to greater distances, thus allowing astronomers to probe earlier epochs in the evolution of the Universe. "The reason this result is so significant is that we need the Hubble constant to tell us the size of the Universe, its age, and how much matter it contains," said Max Bonamente from the University of Alabama in Huntsville and NASA's Marshall Space Flight Center (MSFC) in Huntsville, Ala., lead author on the paper describing the results. "Astronomers absolutely need to trust this number because we use it for countless calculations." Illustration of Sunyaev-Zeldovich Effect Illustration of Sunyaev-Zeldovich Effect The Hubble constant is calculated by measuring the speed at which objects are moving away from us and dividing by their distance. Most of the previous attempts to determine the Hubble constant have involved using a multi-step, or distance ladder, approach in which the distance to nearby galaxies is used as the basis for determining greater distances. The most common approach has been to use a well-studied type of pulsating star known as a Cepheid variable, in conjunction with more distant supernovae to trace distances across the Universe. Scientists using this method and observations from the Hubble Space Telescope were able to measure the Hubble constant to within 10%. However, only independent checks would give them the confidence they desired, considering that much of our understanding of the Universe hangs in the balance. Chandra X-ray Image of MACS J1149.5+223 Chandra X-ray Image of MACS J1149.5+223 By combining X-ray data from Chandra with radio observations of galaxy clusters, the team determined the distances to 38 galaxy clusters ranging from 1.4 billion to 9.3 billion

  12. Surface-Based Protein Binding Pocket Similarity

    PubMed Central

    Spitzer, Russell; Cleves, Ann E.; Jain, Ajay N.

    2011-01-01

    Protein similarity comparisons may be made on a local or global basis and may consider sequence information or differing levels of structural information. We present a local 3D method that compares protein binding site surfaces in full atomic detail. The approach is based on the morphological similarity method which has been widely applied for global comparison of small molecules. We apply the method to all-by-all comparisons two sets of human protein kinases, a very diverse set of ATP-bound proteins from multiple species, and three heterogeneous benchmark protein binding site data sets. Cases of disagreement between sequence-based similarity and binding site similarity yield informative examples. Where sequence similarity is very low, high pocket similarity can reliably identify important binding motifs. Where sequence similarity is very high, significant differences in pocket similarity are related to ligand binding specificity and similarity. Local protein binding pocket similarity provides qualitatively complementary information to other approaches, and it can yield quantitative information in support of functional annotation. PMID:21769944

  13. Similarity increases altruistic punishment in humans.

    PubMed

    Mussweiler, Thomas; Ockenfels, Axel

    2013-11-26

    Humans are attracted to similar others. As a consequence, social networks are homogeneous in sociodemographic, intrapersonal, and other characteristics--a principle called homophily. Despite abundant evidence showing the importance of interpersonal similarity and homophily for human relationships, their behavioral correlates and cognitive foundations are poorly understood. Here, we show that perceived similarity substantially increases altruistic punishment, a key mechanism underlying human cooperation. We induced (dis)similarity perception by manipulating basic cognitive mechanisms in an economic cooperation game that included a punishment phase. We found that similarity-focused participants were more willing to punish others' uncooperative behavior. This influence of similarity is not explained by group identity, which has the opposite effect on altruistic punishment. Our findings demonstrate that pure similarity promotes reciprocity in ways known to encourage cooperation. At the same time, the increased willingness to punish norm violations among similarity-focused participants provides a rationale for why similar people are more likely to build stable social relationships. Finally, our findings show that altruistic punishment is differentially involved in encouraging cooperation under pure similarity vs. in-group conditions.

  14. Similarity increases altruistic punishment in humans

    PubMed Central

    Mussweiler, Thomas; Ockenfels, Axel

    2013-01-01

    Humans are attracted to similar others. As a consequence, social networks are homogeneous in sociodemographic, intrapersonal, and other characteristics—a principle called homophily. Despite abundant evidence showing the importance of interpersonal similarity and homophily for human relationships, their behavioral correlates and cognitive foundations are poorly understood. Here, we show that perceived similarity substantially increases altruistic punishment, a key mechanism underlying human cooperation. We induced (dis)similarity perception by manipulating basic cognitive mechanisms in an economic cooperation game that included a punishment phase. We found that similarity-focused participants were more willing to punish others’ uncooperative behavior. This influence of similarity is not explained by group identity, which has the opposite effect on altruistic punishment. Our findings demonstrate that pure similarity promotes reciprocity in ways known to encourage cooperation. At the same time, the increased willingness to punish norm violations among similarity-focused participants provides a rationale for why similar people are more likely to build stable social relationships. Finally, our findings show that altruistic punishment is differentially involved in encouraging cooperation under pure similarity vs. in-group conditions. PMID:24218611

  15. Sequence independent amplification of DNA

    DOEpatents

    Bohlander, Stefan K.

    1998-01-01

    The present invention is a rapid sequence-independent amplification procedure (SIA). Even minute amounts of DNA from various sources can be amplified independent of any sequence requirements of the DNA or any a priori knowledge of any sequence characteristics of the DNA to be amplified. This method allows, for example the sequence independent amplification of microdissected chromosomal material and the reliable construction of high quality fluorescent in situ hybridization (FISH) probes from YACs or from other sources. These probes can be used to localize YACs on metaphase chromosomes but also--with high efficiency--in interphase nuclei.

  16. Sequence independent amplification of DNA

    DOEpatents

    Bohlander, S.K.

    1998-03-24

    The present invention is a rapid sequence-independent amplification procedure (SIA). Even minute amounts of DNA from various sources can be amplified independent of any sequence requirements of the DNA or any a priori knowledge of any sequence characteristics of the DNA to be amplified. This method allows, for example, the sequence independent amplification of microdissected chromosomal material and the reliable construction of high quality fluorescent in situ hybridization (FISH) probes from YACs or from other sources. These probes can be used to localize YACs on metaphase chromosomes but also--with high efficiency--in interphase nuclei. 25 figs.

  17. Semantic self-knowledge and episodic self-knowledge: independent or interrelated representations?

    PubMed

    Sakaki, Michiko

    2007-01-01

    In this study of the structure of self-knowledge, we examined priming effects for the recall of personal episodes in order to investigate whether abstract trait knowledge and personal episodes are independent mental representations. We found that accessing similar abstract representations of traits facilitated a faster recall of related personal episodes than did accessing irrelevant abstract representations of traits (Experiments 1 and 2), reading a nonword prime (Experiments 2 and 3), accessing knowledge of one's mother (Experiment 3), or accessing semantic knowledge (Experiment 3). Contrary to previous findings, which indicated that abstract trait knowledge is represented independently of related personal episodes (e.g., Klein & Loftus, 1993; Tulving, 1993), our results suggest that abstract trait knowledge is associated with personal episodes, and therefore that semantic self-knowledge is associated with episodic self-knowledge in long-term self-knowledge.

  18. Earthquake Fingerprints: Representing Earthquake Waveforms for Similarity-Based Detection

    NASA Astrophysics Data System (ADS)

    Bergen, K.; Beroza, G. C.

    2016-12-01

    New earthquake detection methods, such as Fingerprint and Similarity Thresholding (FAST), use fast approximate similarity search to identify similar waveforms in long-duration data without templates (Yoon et al. 2015). These methods have two key components: fingerprint extraction and an efficient search algorithm. Fingerprint extraction converts waveforms into fingerprints, compact signatures that represent short-duration waveforms for identification and search. Earthquakes are detected using an efficient indexing and search scheme, such as locality-sensitive hashing, that identifies similar waveforms in a fingerprint database. The quality of the search results, and thus the earthquake detection results, is strongly dependent on the fingerprinting scheme. Fingerprint extraction should map similar earthquake waveforms to similar waveform fingerprints to ensure a high detection rate, even under additive noise and small distortions. Additionally, fingerprints corresponding to noise intervals should have mutually dissimilar fingerprints to minimize false detections. In this work, we compare the performance of multiple fingerprint extraction approaches for the earthquake waveform similarity search problem. We apply existing audio fingerprinting (used in content-based audio identification systems) and time series indexing techniques and present modified versions that are specifically adapted for seismic data. We also explore data-driven fingerprinting approaches that can take advantage of labeled or unlabeled waveform data. For each fingerprinting approach we measure its ability to identify similar waveforms in a low signal-to-noise setting, and quantify the trade-off between true and false detection rates in the presence of persistent noise sources. We compare the performance using known event waveforms from eight independent stations in the Northern California Seismic Network.

  19. Cognitive Independence Development by Observations

    NASA Astrophysics Data System (ADS)

    Stoev, Alexey; Muglova, P.

    The didactic effectiveness of new methods of independent educational - research activity of students has been investigated. The difference in the level of theoretical knowledge and observational skills of the students from six problem groups of the Astronomy school at the Public astronomical observatory in Stara Zagora has been objectively determined by tests in the experimental and control groups. The didactic characteristics of the educational - cognitive method of astronomical observation have been determined by epistemological analysis. A system of didactic tests for studying the development of cognitive independence and activity of the students during their participation in astronomical research observations has been developed and experimented. A special system of methods for application of the astronomical research observations for development of the cognitive independence of the students has been formulated. Original methods of determining the level of student’s cognitive independence during their training for observation of the total solar eclipses in 1990 1999 and 2001 have been applied.

  20. Independent Schools: Landscape and Learnings.

    ERIC Educational Resources Information Center

    Oates, William A.

    1981-01-01

    Examines American independent schools (parochial, southern segregated, and private institutions) in terms of their funding, expenditures, changing enrollment patterns, teacher-student ratios, and societal functions. Journal available from Daedalus Subscription Department, 1172 Commonwealth Ave., Boston, MA 02132. (AM)

  1. [Editorial independence and scientific publications].

    PubMed

    Matías-Guiu, J; García-Ramos, R

    2010-01-01

    Various cases of editors of leading journals resigning has led to a debate on the question of editorial independence, understood as the unconditional freedom of editors to approve the contents of their journals. An analysis is made of cases in which editorial independence has been questioned, as well as the position those who resolutely defend it against those who consider that it must be limited by the institutions of which they are their organs of expression. Editors of scientific publications not only have to be judges of the articles they receive, but they must also be judged by their decisions, and editorial independence cannot be a refuge for personal stances. By independence it must be understood as the meticulousness in accepting manuscripts and the application of transparent criteria.

  2. Technology for Independent Living: Sourcebook.

    ERIC Educational Resources Information Center

    Enders, Alexandra, Ed.

    This sourcebook provides information for the practical implementation of independent living technology in the everyday rehabilitation process. "Information Services and Resources" lists databases, clearinghouses, networks, research and development programs, toll-free telephone numbers, consumer protection caveats, selected publications, and…

  3. Independent Schools: Landscape and Learnings.

    ERIC Educational Resources Information Center

    Oates, William A.

    1981-01-01

    Examines American independent schools (parochial, southern segregated, and private institutions) in terms of their funding, expenditures, changing enrollment patterns, teacher-student ratios, and societal functions. Journal available from Daedalus Subscription Department, 1172 Commonwealth Ave., Boston, MA 02132. (AM)

  4. Similarity effects in visual working memory.

    PubMed

    Jiang, Yuhong V; Lee, Hyejin J; Asaad, Anthony; Remington, Roger

    2016-04-01

    Perceptual similarity is an important property of multiple stimuli. Its computation supports a wide range of cognitive functions, including reasoning, categorization, and memory recognition. It is important, therefore, to determine why previous research has found conflicting effects of inter-item similarity on visual working memory. Studies reporting a similarity advantage have used simple stimuli whose similarity varied along a featural continuum. Studies reporting a similarity disadvantage have used complex stimuli from either a single or multiple categories. To elucidate stimulus conditions for similarity effects in visual working memory, we tested memory for complex stimuli (faces) whose similarity varied along a morph continuum. Participants encoded 3 morphs generated from a single face identity in the similar condition, or 3 morphs generated from different face identities in the dissimilar condition. After a brief delay, a test face appeared at one of the encoding locations for participants to make a same/different judgment. Two experiments showed that similarity enhanced memory accuracy without changing the response criterion. These findings support previous computational models that incorporate featural variance as a component of working memory load. They delineate limitations of models that emphasize cortical resources or response decisions.

  5. Notions of similarity for systems biology models.

    PubMed

    Henkel, Ron; Hoehndorf, Robert; Kacprowski, Tim; Knüpfer, Christian; Liebermeister, Wolfram; Waltemath, Dagmar

    2016-10-14

    Systems biology models are rapidly increasing in complexity, size and numbers. When building large models, researchers rely on software tools for the retrieval, comparison, combination and merging of models, as well as for version control. These tools need to be able to quantify the differences and similarities between computational models. However, depending on the specific application, the notion of 'similarity' may greatly vary. A general notion of model similarity, applicable to various types of models, is still missing. Here we survey existing methods for the comparison of models, introduce quantitative measures for model similarity, and discuss potential applications of combined similarity measures. To frame model comparison as a general problem, we describe a theoretical approach to defining and computing similarities based on a combination of different model aspects. The six aspects that we define as potentially relevant for similarity are underlying encoding, references to biological entities, quantitative behaviour, qualitative behaviour, mathematical equations and parameters and network structure. We argue that future similarity measures will benefit from combining these model aspects in flexible, problem-specific ways to mimic users' intuition about model similarity, and to support complex model searches in databases.

  6. Similarity principle and rejection of Gibbs paradox

    NASA Astrophysics Data System (ADS)

    Lin, Shu-Kun

    2000-03-01

    Gibbs Paradox says that entropy of mixing or assembling decreases discotinuously with the increase in the property similarity. After the rejection of the Gibbs paradox statement (see papers cited at website http://www.mdpi.org/lin/), the similarity principle has been developed: If all the other conditions remain constant, the higher the similarity among the components is, the higher value of entropy of the mixing, the assembling or the chemical bond formation process will be, the more spontaneous the mixing, the assembling or the chemical bond formation process will be, and the more stable the mixture, the assemblage or the chemical bond will be. The similarity principle is very useful. If one wants to mix substances, increase the similarity (of relevant properties); if one plans to separate the substances as phases, reduce their similarity! Then, the desirable processes of mixing or separation will happen spontaneously. Normally by changing temperature ( similarity is related to Boltzmann factor) and pressure, one can control the similarity and in turn, direct the process towards the desired direction. Higher temperature and pressure leads to higher similarity. This theory is important in understanding molecular recognition, self-organization, molecular assembling and molecular replication.

  7. Matched Molecular Series: Measuring SAR Similarity.

    PubMed

    Ehmki, Emanuel S R; Kramer, Christian

    2017-05-22

    Suggesting novel compounds to be made on the basis of similarity to a previously seen structure-activity relationship (SAR) requires a measure for SAR similarity. While SAR similarity has intuitively been used by medicinal chemists for decades, no systematic comparison of candidate similarity metrics has been published to date. With this publication, we attempt to close that gap by providing a statistical framework that allows comparison of SAR similarity metrics by their ability to rank series that provide the best activity prediction of novel substituents. This prediction is a result of a two-step process that involves (a) judging the similarity between series and (b) transferring the SAR from one series to the other. We tested several SAR similarity metrics and found that a centered RMSD (cRMSD) in combination with a lineaar-regression-based prediction interpolation ranks SAR profiles best. Based on that ranking we can, with a given confidence, suggest novel substituents to be tested. The superiority of the cRMSD can be explained on the basis of experimental uncertainty of affinity data and measured affinity differences. The ability to measure SAR similarity is central to applications like matched molecular series (MMS) analysis, whose applicability depends on whether there is a potential for SAR transferability between series. With the new SAR similarity metric introduced here, we show how MMS can be used in a medicinal chemistry setting as an idea generator and a semiquantitative prediction tool.

  8. Experimental interference of independent photons.

    PubMed

    Kaltenbaek, Rainer; Blauensteiner, Bibiane; Zukowski, Marek; Aspelmeyer, Markus; Zeilinger, Anton

    2006-06-23

    Interference of photons emerging from independent sources is essential for modern quantum-information processing schemes, above all quantum repeaters and linear-optics quantum computers. We report an observation of nonclassical interference of two single photons originating from two independent, separated sources, which were actively synchronized with a rms timing jitter of 260 fs. The resulting (two-photon) interference visibility was (83+/-4)%.

  9. Independence test for sparse data

    NASA Astrophysics Data System (ADS)

    García, J. E.; González-López, V. A.

    2016-06-01

    In this paper a new non-parametric independence test is presented. García and González-López (2014) [1] introduced the LIS test for the hypothesis of independence between two continuous random variables, the test proposed in this work is a generalization of the LIS test. The new test does not require the assumption of continuity for the random variables, it test is applied to two datasets and also compared with the Pearson's Chi-squared test.

  10. Hybrid control approach for seismic coupling of two similar adjacent structures

    NASA Astrophysics Data System (ADS)

    Park, Kwan-Soon; Ok, Seung-Yong

    2015-08-01

    This study describes an optimal hybrid control approach of two similar adjacent buildings for seismic performance improvement, for which the passive dampers are used as link members between the two parallel buildings and the active control devices are installed as tendon-type devices between two successive floors in the buildings. Throughout this configuration, the passive coupling dampers modulate the relative responses between the two buildings and the active control devices modulate the inter-story responses of each building. In order to achieve global optimal control performance, genetic algorithm is employed to perform an integrated design approach for the system of buildings and hybrid control devices. Through the optimization process, the passive and active devices are optimally distributed along the floors and, simultaneously, their damping capacities and active controllers are configured in accordance with the distribution. The proposed approach is demonstrated in comparison with typical active control system which consists of two independent active systems without any connections between two buildings, each being optimal for one particular building. The numerical simulation results for a system of 20-story and 16-story buildings reveal that the proposed system can guarantee the competent control performance over the typical independent active system with less control forces and powers. As a result, it is proved that the proposed approach enables the simultaneous optimization of the control performance and the control cost.

  11. Second-order schedules and the problem of conditioned reinforcement

    PubMed Central

    Stubbs, D. Alan

    1971-01-01

    Thirteen pigeons were exposed to a variety of second-order schedules in which responding under a component schedule was reinforced according to a schedule of reinforcement. Under different conditions, completion of each component resulted in either (1) the brief presentation of a stimulus also present during reinforcement (pairing operation), (2) the brief presentation of a stimulus not present during reinforcement (nonpairing operation), or (3) no brief stimulus presentation (tandem). Brief-stimulus presentations engendered a pattern of responding within components similar to that engendered by food. Patterning was observed when fixed-interval and fixed-ratio components were maintained under fixed- and variable-ratio and fixed- and variable-interval schedules. There were no apparent differences in performance under pairing and nonpairing conditions in any study. The properties of the stimuli presented in brief-stimulus operations produced different effects on response patterning. In one study, similar effects on performance were found whether brief-stimulus presentations were response-produced or delivered independently of responding. Response patterning did not occur when the component schedule under which a nonpaired stimulus was produced occurred independently of the food schedule. The results suggest a reevaluation of the role of conditioned reinforcement in second-order schedule performance. The similarity of behavior under pairing and nonpairing operations is consistent with two hypotheses: (1) the major effect is due to the discriminative properties of the brief stimulus; (2) the scheduling operation under which the paired or nonpaired stimulus is presented can establish it as a reinforcer. PMID:16811549

  12. Similarity relations for anisotropic scattering in absorbing media

    NASA Astrophysics Data System (ADS)

    Graaff, Reindert; Aarnoudse, Jan G.; de Mul, Frits F.; Jentink, Henk W.

    1993-02-01

    The validity of the similarity parameter (Sigma) 's equalsV (Sigma) s (1 - g), the reduced scattering coefficient, where g is the average cosine of the scattering phase function is investigated. Attenuation coefficients (alpha) and diffusion patterns are obtained from solutions of the transport equation for isotropic scattering and Rayleigh-Gans scattering, applied to infinite media. Similarity is studied for the attenuation coefficient (alpha) , as well as for the Kubelka-Munk absorption and backscattering coefficients in the positive and negative directions, and for predictions of the internal reflection at interfaces. Similarity between solutions of the Boltzmann equation for highly forward scattering and isotropic scattering (g equals 0) exist only when (Sigma) a << (Sigma) s (1 - g). However, because similarity between results, both with g > 0.9, is independent of the value of the absorption coefficient, it is advantageous to simulate highly forward scattering media like biological tissues with g > 0.9, e.g., by Monte Carlo simulations, instead of using isotropic scattering or diffusion theory. Monte Carlo simulations on slabs confirm the deviations from the diffusion approximation and show the behavior near boundaries. Application of similarity may save calculation time in Monte Carlo simulations, because simulation with a lower value for g will increase the mean free path.

  13. Some Effects of Similarity Self-Disclosure

    ERIC Educational Resources Information Center

    Murphy, Kevin C.; Strong, Stanley R.

    1972-01-01

    College males were interviewed about how college had altered their friendships, values, and plans. The interviewers diclosed experiences and feelings similar to those revealed by the students. Results support Byrne's Law of Similarity in generating interpersonal attraction in the interview and suggest that the timing of self-disclosures is…

  14. Stability of similarity measurements for bipartite networks

    NASA Astrophysics Data System (ADS)

    Liu, Jian-Guo; Hou, Lei; Pan, Xue; Guo, Qiang; Zhou, Tao

    2016-01-01

    Similarity is a fundamental measure in network analyses and machine learning algorithms, with wide applications ranging from personalized recommendation to socio-economic dynamics. We argue that an effective similarity measurement should guarantee the stability even under some information loss. With six bipartite networks, we investigate the stabilities of fifteen similarity measurements by comparing the similarity matrixes of two data samples which are randomly divided from original data sets. Results show that, the fifteen measurements can be well classified into three clusters according to their stabilities, and measurements in the same cluster have similar mathematical definitions. In addition, we develop a top-n-stability method for personalized recommendation, and find that the unstable similarities would recommend false information to users, and the performance of recommendation would be largely improved by using stable similarity measurements. This work provides a novel dimension to analyze and evaluate similarity measurements, which can further find applications in link prediction, personalized recommendation, clustering algorithms, community detection and so on.

  15. Attitude Similarity, Topic Importance, and Psychotherapeutic Attraction

    ERIC Educational Resources Information Center

    Cheney, Thomas

    1975-01-01

    The effect of attitude similarity and topic importance on attraction was studied by exposing 75 prison inmates, incarcerated for public intoxication, to varying attitudes of a psychotherapist. Subjects were more attracted to the therapist after receiving alcohol items regardless of degree of similarity expressed. (Author)

  16. Perceived Similarity, Proactive Adjustment, and Organizational Socialization

    ERIC Educational Resources Information Center

    Kammeyer-Mueller, John D.; Livingston, Beth A.; Liao, Hui

    2011-01-01

    The present study explores how perceived demographic and attitudinal similarity can influence proactive behavior among organizational newcomers. We propose that newcomers who perceive themselves as similar to their co-workers will be more willing to seek new information or build relationships, which in turn will lead to better long-term…

  17. Stability of similarity measurements for bipartite networks.

    PubMed

    Liu, Jian-Guo; Hou, Lei; Pan, Xue; Guo, Qiang; Zhou, Tao

    2016-01-04

    Similarity is a fundamental measure in network analyses and machine learning algorithms, with wide applications ranging from personalized recommendation to socio-economic dynamics. We argue that an effective similarity measurement should guarantee the stability even under some information loss. With six bipartite networks, we investigate the stabilities of fifteen similarity measurements by comparing the similarity matrixes of two data samples which are randomly divided from original data sets. Results show that, the fifteen measurements can be well classified into three clusters according to their stabilities, and measurements in the same cluster have similar mathematical definitions. In addition, we develop a top-n-stability method for personalized recommendation, and find that the unstable similarities would recommend false information to users, and the performance of recommendation would be largely improved by using stable similarity measurements. This work provides a novel dimension to analyze and evaluate similarity measurements, which can further find applications in link prediction, personalized recommendation, clustering algorithms, community detection and so on.

  18. Guaranteed classification via regularized similarity learning.

    PubMed

    Guo, Zheng-Chu; Ying, Yiming

    2014-03-01

    Learning an appropriate (dis)similarity function from the available data is a central problem in machine learning, since the success of many machine learning algorithms critically depends on the choice of a similarity function to compare examples. Despite many approaches to similarity metric learning that have been proposed, there has been little theoretical study on the links between similarity metric learning and the classification performance of the resulting classifier. In this letter, we propose a regularized similarity learning formulation associated with general matrix norms and establish their generalization bounds. We show that the generalization error of the resulting linear classifier can be bounded by the derived generalization bound of similarity learning. This shows that a good generalization of the learned similarity function guarantees a good classification of the resulting linear classifier. Our results extend and improve those obtained by Bellet, Habrard, and Sebban (2012). Due to the techniques dependent on the notion of uniform stability (Bousquet & Elisseeff, 2002), the bound obtained there holds true only for the Frobenius matrix-norm regularization. Our techniques using the Rademacher complexity (Bartlett & Mendelson, 2002) and its related Khinchin-type inequality enable us to establish bounds for regularized similarity learning formulations associated with general matrix norms, including sparse L1-norm and mixed (2,1)-norm.

  19. Structure Mapping in Analogy and Similarity.

    ERIC Educational Resources Information Center

    Gentner, Dedre; Markman, Arthur B.

    1997-01-01

    It is suggested that both similarity and analogy involve a process of structural alignment and mapping. The structure mapping process is described as it has been worked out for analogy, and this view is then extended to similarity and used to generate new predictions. (SLD)

  20. Similar methodological analysis involving the user experience.

    PubMed

    Almeida e Silva, Caio Márcio; Okimoto, Maria Lúcia R L; Tanure, Raffaela Leane Zenni

    2012-01-01

    This article deals with the use of a protocol for analysis of similar methodological analysis related to user experience. For both, were selected articles recounting experiments in the area. They were analyze based on the similar analysis protocol and finally, synthesized and associated.

  1. Stability of similarity measurements for bipartite networks

    PubMed Central

    Liu, Jian-Guo; Hou, Lei; Pan, Xue; Guo, Qiang; Zhou, Tao

    2016-01-01

    Similarity is a fundamental measure in network analyses and machine learning algorithms, with wide applications ranging from personalized recommendation to socio-economic dynamics. We argue that an effective similarity measurement should guarantee the stability even under some information loss. With six bipartite networks, we investigate the stabilities of fifteen similarity measurements by comparing the similarity matrixes of two data samples which are randomly divided from original data sets. Results show that, the fifteen measurements can be well classified into three clusters according to their stabilities, and measurements in the same cluster have similar mathematical definitions. In addition, we develop a top-n-stability method for personalized recommendation, and find that the unstable similarities would recommend false information to users, and the performance of recommendation would be largely improved by using stable similarity measurements. This work provides a novel dimension to analyze and evaluate similarity measurements, which can further find applications in link prediction, personalized recommendation, clustering algorithms, community detection and so on. PMID:26725688

  2. Learning deep similarity in fundus photography

    NASA Astrophysics Data System (ADS)

    Chudzik, Piotr; Al-Diri, Bashir; Caliva, Francesco; Ometto, Giovanni; Hunter, Andrew

    2017-02-01

    Similarity learning is one of the most fundamental tasks in image analysis. The ability to extract similar images in the medical domain as part of content-based image retrieval (CBIR) systems has been researched for many years. The vast majority of methods used in CBIR systems are based on hand-crafted feature descriptors. The approximation of a similarity mapping for medical images is difficult due to the big variety of pixel-level structures of interest. In fundus photography (FP) analysis, a subtle difference in e.g. lesions and vessels shape and size can result in a different diagnosis. In this work, we demonstrated how to learn a similarity function for image patches derived directly from FP image data without the need of manually designed feature descriptors. We used a convolutional neural network (CNN) with a novel architecture adapted for similarity learning to accomplish this task. Furthermore, we explored and studied multiple CNN architectures. We show that our method can approximate the similarity between FP patches more efficiently and accurately than the state-of- the-art feature descriptors, including SIFT and SURF using a publicly available dataset. Finally, we observe that our approach, which is purely data-driven, learns that features such as vessels calibre and orientation are important discriminative factors, which resembles the way how humans reason about similarity. To the best of authors knowledge, this is the first attempt to approximate a visual similarity mapping in FP.

  3. Marking Student Programs Using Graph Similarity

    ERIC Educational Resources Information Center

    Naude, Kevin A.; Greyling, Jean H.; Vogts, Dieter

    2010-01-01

    We present a novel approach to the automated marking of student programming assignments. Our technique quantifies the structural similarity between unmarked student submissions and marked solutions, and is the basis by which we assign marks. This is accomplished through an efficient novel graph similarity measure ("AssignSim"). Our experiments…

  4. Documents Similarity Measurement Using Field Association Terms.

    ERIC Educational Resources Information Center

    Atlam, El-Sayed; Fuketa, M.; Morita, K.; Aoe, Jun-ichi

    2003-01-01

    Discussion of text analysis and information retrieval and measurement of document similarity focuses on a new text manipulation system called FA (field association)-Sim that is useful for retrieving information in large heterogeneous texts and for recognizing content similarity in text excerpts. Discusses recall and precision, automatic indexing…

  5. Documents Similarity Measurement Using Field Association Terms.

    ERIC Educational Resources Information Center

    Atlam, El-Sayed; Fuketa, M.; Morita, K.; Aoe, Jun-ichi

    2003-01-01

    Discussion of text analysis and information retrieval and measurement of document similarity focuses on a new text manipulation system called FA (field association)-Sim that is useful for retrieving information in large heterogeneous texts and for recognizing content similarity in text excerpts. Discusses recall and precision, automatic indexing…

  6. Perceived Similarity, Proactive Adjustment, and Organizational Socialization

    ERIC Educational Resources Information Center

    Kammeyer-Mueller, John D.; Livingston, Beth A.; Liao, Hui

    2011-01-01

    The present study explores how perceived demographic and attitudinal similarity can influence proactive behavior among organizational newcomers. We propose that newcomers who perceive themselves as similar to their co-workers will be more willing to seek new information or build relationships, which in turn will lead to better long-term…

  7. Mining Diagnostic Assessment Data for Concept Similarity

    ERIC Educational Resources Information Center

    Madhyastha, Tara; Hunt, Earl

    2009-01-01

    This paper introduces a method for mining multiple-choice assessment data for similarity of the concepts represented by the multiple choice responses. The resulting similarity matrix can be used to visualize the distance between concepts in a lower-dimensional space. This gives an instructor a visualization of the relative difficulty of concepts…

  8. Ultra-accurate collaborative information filtering via directed user similarity

    NASA Astrophysics Data System (ADS)

    Guo, Q.; Song, W.-J.; Liu, J.-G.

    2014-07-01

    A key challenge of the collaborative filtering (CF) information filtering is how to obtain the reliable and accurate results with the help of peers' recommendation. Since the similarities from small-degree users to large-degree users would be larger than the ones in opposite direction, the large-degree users' selections are recommended extensively by the traditional second-order CF algorithms. By considering the users' similarity direction and the second-order correlations to depress the influence of mainstream preferences, we present the directed second-order CF (HDCF) algorithm specifically to address the challenge of accuracy and diversity of the CF algorithm. The numerical results for two benchmark data sets, MovieLens and Netflix, show that the accuracy of the new algorithm outperforms the state-of-the-art CF algorithms. Comparing with the CF algorithm based on random walks proposed by Liu et al. (Int. J. Mod. Phys. C, 20 (2009) 285) the average ranking score could reach 0.0767 and 0.0402, which is enhanced by 27.3% and 19.1% for MovieLens and Netflix, respectively. In addition, the diversity, precision and recall are also enhanced greatly. Without relying on any context-specific information, tuning the similarity direction of CF algorithms could obtain accurate and diverse recommendations. This work suggests that the user similarity direction is an important factor to improve the personalized recommendation performance.

  9. Investigation of psychophysical similarity measures for selection of similar images in the diagnosis of clustered microcalcifications on mammograms

    SciTech Connect

    Muramatsu, Chisako; Li Qiang; Schmidt, Robert; Shiraishi, Junji; Doi, Kunio

    2008-12-15

    The presentation of images with lesions of known pathology that are similar to an unknown lesion may be helpful to radiologists in the diagnosis of challenging cases for improving the diagnostic accuracy and also for reducing variation among different radiologists. The authors have been developing a computerized scheme for automatically selecting similar images with clustered microcalcifications on mammograms from a large database. For similar images to be useful, they must be similar from the point of view of the diagnosing radiologists. In order to select such images, subjective similarity ratings were obtained for a number of pairs of clustered microcalcifications by breast radiologists for establishment of a ''gold standard'' of image similarity, and the gold standard was employed for determination and evaluation of the selection of similar images. The images used in this study were obtained from the Digital Database for Screening Mammography developed by the University of South Florida. The subjective similarity ratings for 300 pairs of images with clustered microcalcifications were determined by ten breast radiologists. The authors determined a number of image features which represent the characteristics of clustered microcalcifications that radiologists would use in their diagnosis. For determination of objective similarity measures, an artificial neural network (ANN) was employed. The ANN was trained with the average subjective similarity ratings as teacher and selected image features as input data. The ANN was trained to learn the relationship between the image features and the radiologists' similarity ratings; therefore, once the training was completed, the ANN was able to determine the similarity, called a psychophysical similarity measure, which was expected to be close to radiologists' impressions, for an unknown pair of clustered microcalcifications. By use of a leave-one-out test method, the best combination of features was selected. The correlation

  10. Investigation of psychophysical similarity measures for selection of similar images in the diagnosis of clustered microcalcifications on mammograms.

    PubMed

    Muramatsu, Chisako; Li, Qiang; Schmidt, Robert; Shiraishi, Junji; Doi, Kunio

    2008-12-01

    The presentation of images with lesions of known pathology that are similar to an unknown lesion may be helpful to radiologists in the diagnosis of challenging cases for improving the diagnostic accuracy and also for reducing variation among different radiologists. The authors have been developing a computerized scheme for automatically selecting similar images with clustered microcalcifications on mammograms from a large database. For similar images to be useful, they must be similar from the point of view of the diagnosing radiologists. In order to select such images, subjective similarity ratings were obtained for a number of pairs of clustered microcalcifications by breast radiologists for establishment of a "gold standard" of image similarity, and the gold standard was employed for determination and evaluation of the selection of similar images. The images used in this study were obtained from the Digital Database for Screening Mammography developed by the University of South Florida. The subjective similarity ratings for 300 pairs of images with clustered microcalcifications were determined by ten breast radiologists. The authors determined a number of image features which represent the characteristics of clustered microcalcifications that radiologists would use in their diagnosis. For determination of objective similarity measures, an artificial neural network (ANN) was employed. The ANN was trained with the average subjective similarity ratings as teacher and selected image features as input data. The ANN was trained to learn the relationship between the image features and the radiologists' similarity ratings; therefore, once the training was completed, the ANN was able to determine the similarity, called a psychophysical similarity measure, which was expected to be close to radiologists' impressions, for an unknown pair of clustered microcalcifications. By use of a leave-one-out test method, the best combination of features was selected. The correlation

  11. Minimal Orderings Revisited

    SciTech Connect

    Peyton, B.W.

    1999-07-01

    When minimum orderings proved too difficult to deal with, Rose, Tarjan, and Leuker instead studied minimal orderings and how to compute them (Algorithmic aspects of vertex elimination on graphs, SIAM J. Comput., 5:266-283, 1976). This paper introduces an algorithm that is capable of computing much better minimal orderings much more efficiently than the algorithm in Rose et al. The new insight is a way to use certain structures and concepts from modern sparse Cholesky solvers to re-express one of the basic results in Rose et al. The new algorithm begins with any initial ordering and then refines it until a minimal ordering is obtained. it is simple to obtain high-quality low-cost minimal orderings by using fill-reducing heuristic orderings as initial orderings for the algorithm. We examine several such initial orderings in some detail.

  12. Drug Promiscuity in PDB: Protein Binding Site Similarity Is Key

    PubMed Central

    Schroeder, Michael

    2013-01-01

    Drug repositioning applies established drugs to new disease indications with increasing success. A pre-requisite for drug repurposing is drug promiscuity (polypharmacology) – a drug’s ability to bind to several targets. There is a long standing debate on the reasons for drug promiscuity. Based on large compound screens, hydrophobicity and molecular weight have been suggested as key reasons. However, the results are sometimes contradictory and leave space for further analysis. Protein structures offer a structural dimension to explain promiscuity: Can a drug bind multiple targets because the drug is flexible or because the targets are structurally similar or even share similar binding sites? We present a systematic study of drug promiscuity based on structural data of PDB target proteins with a set of 164 promiscuous drugs. We show that there is no correlation between the degree of promiscuity and ligand properties such as hydrophobicity or molecular weight but a weak correlation to conformational flexibility. However, we do find a correlation between promiscuity and structural similarity as well as binding site similarity of protein targets. In particular, 71% of the drugs have at least two targets with similar binding sites. In order to overcome issues in detection of remotely similar binding sites, we employed a score for binding site similarity: LigandRMSD measures the similarity of the aligned ligands and uncovers remote local similarities in proteins. It can be applied to arbitrary structural binding site alignments. Three representative examples, namely the anti-cancer drug methotrexate, the natural product quercetin and the anti-diabetic drug acarbose are discussed in detail. Our findings suggest that global structural and binding site similarity play a more important role to explain the observed drug promiscuity in the PDB than physicochemical drug properties like hydrophobicity or molecular weight. Additionally, we find ligand flexibility to have a

  13. Kohlberg and Piaget: Differences and Similarities.

    ERIC Educational Resources Information Center

    Kavathatzopoulos, Iordanis

    1991-01-01

    Discusses the relationship between Lawrence Kohlberg's cognitive-stage theory as a further development of Piaget's moral theory. Argues Kohlberg describes moral thought and not the formation of the independent moral function. Finds Kohlberg's major interest is in the characteristics of stages of individual moral reasoning and the principle of…

  14. Proving universal common ancestry with similar sequences

    PubMed Central

    Martins, Leonardo de Oliveira; Posada, David

    2013-01-01

    Douglas Theobald recently developed an interesting test putatively capable of quantifying the evidence for a Universal Common Ancestry uniting the three domains of life (Eukarya, Archaea and Bacteria) against hypotheses of Independent Origins for some of these domains. We review here his model, in particular in relation to the treatment of Horizontal Gene Transfer (HGT) and to the quality of sequence alignment. PMID:23814665

  15. Comparing structural fingerprints using a literature-based similarity benchmark.

    PubMed

    O'Boyle, Noel M; Sayle, Roger A

    2016-01-01

    The concept of molecular similarity is one of the central ideas in cheminformatics, despite the fact that it is ill-defined and rather difficult to assess objectively. Here we propose a practical definition of molecular similarity in the context of drug discovery: molecules A and B are similar if a medicinal chemist would be likely to synthesise and test them around the same time as part of the same medicinal chemistry program. The attraction of such a definition is that it matches one of the key uses of similarity measures in early-stage drug discovery. If we make the assumption that molecules in the same compound activity table in a medicinal chemistry paper were considered similar by the authors of the paper, we can create a dataset of similar molecules from the medicinal chemistry literature. Furthermore, molecules with decreasing levels of similarity to a reference can be found by either ordering molecules in an activity table by their activity, or by considering activity tables in different papers which have at least one molecule in common. Using this procedure with activity data from ChEMBL, we have created two benchmark datasets for structural similarity that can be used to guide the development of improved measures. Compared to similar results from a virtual screen, these benchmarks are an order of magnitude more sensitive to differences between fingerprints both because of their size and because they avoid loss of statistical power due to the use of mean scores or ranks. We measure the performance of 28 different fingerprints on the benchmark sets and compare the results to those from the Riniker and Landrum (J Cheminf 5:26, 2013. doi:10.1186/1758-2946-5-26) ligand-based virtual screening benchmark. Extended-connectivity fingerprints of diameter 4 and 6 are among the best performing fingerprints when ranking diverse structures by similarity, as is the topological torsion fingerprint. However, when ranking very close analogues, the atom pair fingerprint

  16. REPRODUCIBLE DRUG REPURPOSING: WHEN SIMILARITY DOES NOT SUFFICE.

    PubMed

    Guney, Emre

    2016-01-01

    Repurposing existing drugs for new uses has attracted considerable attention over the past years. To identify potential candidates that could be repositioned for a new indication, many studies make use of chemical, target, and side effect similarity between drugs to train classifiers. Despite promising prediction accuracies of these supervised computational models, their use in practice, such as for rare diseases, is hindered by the assumption that there are already known and similar drugs for a given condition of interest. In this study, using publicly available data sets, we question the prediction accuracies of supervised approaches based on drug similarity when the drugs in the training and the test set are completely disjoint. We first build a Python platform to generate reproducible similarity-based drug repurposing models. Next, we show that, while a simple chemical, target, and side effect similarity based machine learning method can achieve good performance on the benchmark data set, the prediction performance drops sharply when the drugs in the folds of the cross validation are not overlapping and the similarity information within the training and test sets are used independently. These intriguing results suggest revisiting the assumptions underlying the validation scenarios of similarity-based methods and underline the need for unsupervised approaches to identify novel drug uses inside the unexplored pharmacological space. We make the digital notebook containing the Python code to replicate our analysis that involves the drug repurposing platform based on machine learning models and the proposed disjoint cross fold generation method freely available at github.com/emreg00/repurpose.

  17. Shape similarity analysis of regions of interest in medical images

    NASA Astrophysics Data System (ADS)

    Wang, Qiang; Charisi, Amalia; Latecki, Longin Jan; Gee, James; Megalooikonomou, Vasilis

    2010-03-01

    In this work, we introduce a new representation technique of 2D contour shapes and a sequence similarity measure to characterize 2D regions of interest in medical images. First, we define a distance function on contour points in order to map the shape of a given contour to a sequence of real numbers. Thus, the computation of shape similarity is reduced to the matching of the obtained sequences. Since both a query and a target sequence may be noisy, i.e., contain some outlier elements, it is desirable to exclude the outliers in order to obtain a robust matching performance. For the computation of shape similarity, we propose the use of an algorithm which performs elastic matching of two sequences. The contribution of our approach is that, unlike previous works that require images to be warped according to a template image for measuring their similarity, it obviates this need, therefore it can estimate image similarity for any type of medical image in a fast and efficient manner. To demonstrate our method's applicability, we analyzed a brain image dataset consisting of corpus callosum shapes, and we investigated the structural differences between children with chromosome 22q11.2 deletion syndrome and controls. Our findings indicate that our method is quite effective and it can be easily applied on medical diagnosis in all cases of which shape difference is an important clue.

  18. Similarity analysis of compressor tip clearance flow structure

    NASA Technical Reports Server (NTRS)

    Chen, G. T.; Greitzer, E. M.; Tan, C. S.; Marble, F. E.

    1991-01-01

    A new approach is presented for analyzing compressor tip clearance flow. The basic idea is that the clearance velocity field can be (approximately) decomposed into independent throughflow and crossflow, since chordwise pressure gradients are much smaller than normal pressure gradients in the clearance region. As in the slender body approximation in external aerodynamics, this description implies that the three-dimensional steady clearance flow can be viewed as a two-dimensional, unsteady flow. Using this approach, a similarity scaling for the crossflow in the clearance region is developed and a generalized description of the clearance vortex is derived. Calculations based on the similarity scaling agree well with a wide range of experimental data in regard to flow features such as crossflow velocity field, static pressure field, and tip clearance vortex trajectory.

  19. New opportunities seen for independents

    SciTech Connect

    Adams, G.A. )

    1990-10-22

    The collapse of gas and oil prices in the mid-1980s significantly reduced the number of independent exploration companies. At the same time, a fundamental shift occurred among major oil companies as they allocated their exploration budgets toward international operations and made major production purchases. Several large independents also embraced a philosophy of budget supplementation through joint venture partnership arrangements. This has created a unique and unusual window of opportunity for the smaller independents (defined for this article as exploration and production companies with a market value of less than $1 billion) to access the extensive and high quality domestic prospect inventories of the major and large independent oil and gas companies and to participate in the search for large reserve targets on attractive joint venture terms. Participation in these types of joint ventures, in conjunction with internally generated plays selected through the use of today's advanced technology (computer-enhanced, high-resolution seismic; horizontal drilling; etc.) and increasing process for oil and natural gas, presents the domestic exploration-oriented independent with an attractive money-making opportunity for the 1990s.

  20. Measure of Node Similarity in Multilayer Networks

    PubMed Central

    Mollgaard, Anders; Zettler, Ingo; Dammeyer, Jesper; Jensen, Mogens H.; Lehmann, Sune; Mathiesen, Joachim

    2016-01-01

    The weight of links in a network is often related to the similarity of the nodes. Here, we introduce a simple tunable measure for analysing the similarity of nodes across different link weights. In particular, we use the measure to analyze homophily in a group of 659 freshman students at a large university. Our analysis is based on data obtained using smartphones equipped with custom data collection software, complemented by questionnaire-based data. The network of social contacts is represented as a weighted multilayer network constructed from different channels of telecommunication as well as data on face-to-face contacts. We find that even strongly connected individuals are not more similar with respect to basic personality traits than randomly chosen pairs of individuals. In contrast, several socio-demographics variables have a significant degree of similarity. We further observe that similarity might be present in one layer of the multilayer network and simultaneously be absent in the other layers. For a variable such as gender, our measure reveals a transition from similarity between nodes connected with links of relatively low weight to dis-similarity for the nodes connected by the strongest links. We finally analyze the overlap between layers in the network for different levels of acquaintanceships. PMID:27300084

  1. The baryonic self similarity of dark matter

    SciTech Connect

    Alard, C.

    2014-06-20

    The cosmological simulations indicates that dark matter halos have specific self-similar properties. However, the halo similarity is affected by the baryonic feedback. By using momentum-driven winds as a model to represent the baryon feedback, an equilibrium condition is derived which directly implies the emergence of a new type of similarity. The new self-similar solution has constant acceleration at a reference radius for both dark matter and baryons. This model receives strong support from the observations of galaxies. The new self-similar properties imply that the total acceleration at larger distances is scale-free, the transition between the dark matter and baryons dominated regime occurs at a constant acceleration, and the maximum amplitude of the velocity curve at larger distances is proportional to M {sup 1/4}. These results demonstrate that this self-similar model is consistent with the basics of modified Newtonian dynamics (MOND) phenomenology. In agreement with the observations, the coincidence between the self-similar model and MOND breaks at the scale of clusters of galaxies. Some numerical experiments show that the behavior of the density near the origin is closely approximated by a Einasto profile.

  2. Gait signal analysis with similarity measure.

    PubMed

    Lee, Sanghyuk; Shin, Seungsoo

    2014-01-01

    Human gait decision was carried out with the help of similarity measure design. Gait signal was selected through hardware implementation including all in one sensor, control unit, and notebook with connector. Each gait signal was considered as high dimensional data. Therefore, high dimensional data analysis was considered via heuristic technique such as the similarity measure. Each human pattern such as walking, sitting, standing, and stepping up was obtained through experiment. By the results of the analysis, we also identified the overlapped and nonoverlapped data relation, and similarity measure analysis was also illustrated, and comparison with conventional similarity measure was also carried out. Hence, nonoverlapped data similarity analysis provided the clue to solve the similarity of high dimensional data. Considered high dimensional data analysis was designed with consideration of neighborhood information. Proposed similarity measure was applied to identify the behavior patterns of different persons, and different behaviours of the same person. Obtained analysis can be extended to organize health monitoring system for specially elderly persons.

  3. Gait Signal Analysis with Similarity Measure

    PubMed Central

    Shin, Seungsoo

    2014-01-01

    Human gait decision was carried out with the help of similarity measure design. Gait signal was selected through hardware implementation including all in one sensor, control unit, and notebook with connector. Each gait signal was considered as high dimensional data. Therefore, high dimensional data analysis was considered via heuristic technique such as the similarity measure. Each human pattern such as walking, sitting, standing, and stepping up was obtained through experiment. By the results of the analysis, we also identified the overlapped and nonoverlapped data relation, and similarity measure analysis was also illustrated, and comparison with conventional similarity measure was also carried out. Hence, nonoverlapped data similarity analysis provided the clue to solve the similarity of high dimensional data. Considered high dimensional data analysis was designed with consideration of neighborhood information. Proposed similarity measure was applied to identify the behavior patterns of different persons, and different behaviours of the same person. Obtained analysis can be extended to organize health monitoring system for specially elderly persons. PMID:25110724

  4. ASDC Ordering Tool

    Atmospheric Science Data Center

    2017-02-08

    ... Ordering requires login , searching does not. Projects by science discipline: Aerosols | Clouds | Radiation Budget ... Tropospheric Composition | Field Campaigns All projects Details:  ASDC Ordering Tool ...

  5. First-order inflation

    SciTech Connect

    Kolb, E.W. Chicago Univ., IL . Enrico Fermi Inst.)

    1990-09-01

    In the original proposal, inflation occurred in the process of a strongly first-order phase transition. This model was soon demonstrated to be fatally flawed. Subsequent models for inflation involved phase transitions that were second-order, or perhaps weakly first-order; some even involved no phase transition at all. Recently the possibility of inflation during a strongly first-order phase transition has been revived. In this talk I will discuss some models for first-order inflation, and emphasize unique signatures that result in inflation is realized in a first-order transition. Before discussing first-order inflation, I will briefly review some of the history of inflation to demonstrate how first-order inflation differs from other models. 58 refs., 3 figs.

  6. Independent feature subspace iterative optimization based fuzzy clustering for synthetic aperture radar image segmentation

    NASA Astrophysics Data System (ADS)

    Yu, Hang; Xu, Luping; Feng, Dongzhu; He, Xiaochuan

    2015-01-01

    Synthetic aperture radar (SAR) image segmentation is investigated from feature extraction to algorithm design, which is characterized by two aspects: (1) multiple heterogeneous features are extracted to describe SAR images and the corresponding similarity measures are developed independently to avoid the mutual influences between different features in order to enhance the discriminability of the final similarity between objects. (2) A method called fuzzy clustering based on independent subspace iterative optimization (FCISIO) is proposed. FCISIO integrates multiple features into an objective function which is then iteratively optimized in each feature subspace to obtain final segmentation results. This strategy can protect the distribution structures of the data points in each feature subspace, which realizes an effective way to integrate multiple features of different properties. In order to improve the computation speed and the accuracy of feature description for FCISIO, we design a region merging algorithm before FCISIO which can use many kinds of information to quickly merge regions inside the true segments. Experiments on synthetic and real SAR images show that the proposed method is effective and robust and can obtain good segmentation results with a very short running time.

  7. Fingerprint comparison. I: Similarity of fingerprints.

    PubMed

    Lin, C H; Liu, J H; Osterburg, J W; Nicol, J D

    1982-04-01

    Fingerprints from 61 pairs of male monozygotic twins (MZ), 47 pairs of female MZ, 40 pairs of same-sex male dizygotic twins (DZ), 44 pairs of same-sex female DZ, 4 pairs of opposite-sex DZ, and 28 brothers and 31 sisters of those twins are used for the study of fingerprint similarities. Similarities of fingerprint pattern, ridge count, and minutiae are evaluated for two population groups genetically related to each other in different degrees. It is concluded that fingerprint similarities, including pattern, ridge count, and possibly minutiae, between MZ individuals are significantly higher than those between other population groups, including DZ twins.

  8. Oral rehabilitation to maintain independence.

    PubMed

    Tilman, H H

    1985-02-01

    A child born with missing or deformed upper extremities must learn to develop alternatives for the activities of daily living (ADL). To assure an independent existence, substitutes for nonfunctioning arms and hands must be developed. Teeth can replace hands for all activities that require pinch and grasp, as well as to support adaptive devices for turning pages, typing, drawing and painting. However, without carefully planned dental care, teeth, particularly incisors and canines, will show excessive wear if used for hands over the years. Loss of teeth threatens independence in self-care and in ADL, and loss of self-esteem. Oral health can be restored and retained to maintain function, independence, and esthetics. This case presentation illustrates a challenge and obligation of dentistry in rehabilitation.

  9. On the Ephemeral Nature of the Relationship between Attitude Similarity and Interpersonal Attraction during Initial Encounters.

    ERIC Educational Resources Information Center

    Sunnafrank, Michael J.; Miller, Gerald R.

    A study was conducted to identify the independent and conjoint influence of attitude similarity and initial interactions on interpersonal attraction to relative strangers. The 124 college students who were participants in the study were informed that they would be working on a project with either an attitudinally similar or dissimilar stranger…

  10. Ordering Distributions by Scaled Order Statistics.

    DTIC Science & Technology

    1985-06-01

    survival functions. Thus the ordering (1) is the same as the one discussed by R;uschendorf (1980) and Mosler (1984). Mosler (1984) also discusses the...report, Dept. of Mathematics, University of Arizona. [93 Mosler , K. C. (1984). Stochastic dominance decision rules when the attributes are utility...Gebiete 54, 341-349. [111 Scarsini, M. (1985). Dominance conditions for utility functions with multivariate risk aversion. Technical report, Dept. of

  11. Independent Active Contraction of Extraocular Muscle Compartments

    PubMed Central

    Shin, Andrew; Yoo, Lawrence; Demer, Joseph L.

    2015-01-01

    Purpose. Intramuscular innervation of horizontal rectus extraocular muscle (EOMs) is segregated into superior and inferior (transverse) compartments, whereas all EOMs are also divided into global (GL) and orbital (OL) layers with scleral and pulley insertions, respectively. Mechanical independence between both types of compartments has been demonstrated during passive tensile loading. We examined coupling between EOM compartments during active, ex vivo contraction. Methods. Fresh bovine EOMs were removed, and one compartment of each was coated with hydrophobic petrolatum. Contraction of the uncoated compartment was induced by immersion in a solution of 50 mM CaCl2 at 38°C labeled with sodium fluorescein dye, whereas tensions in both compartments were monitored by strain gauges. Control experiments omitted petrolatum so that the entire EOM contracted. After physiological experiments, EOMs were sectioned transversely to demonstrate specificity of CaCl2 permeation by yellow fluorescence dye excited by blue light. Results. In control experiments without petrolatum, both transverse and GL and OL compartments contracted similarly. Selective compartmental omission of petrolatum caused markedly independent compartmental contraction whether measured at the GL or the OL insertions or for transverse compartments at the scleral insertion. Although some CaCl2 spread occurred, mean (±SD) tension in the coated compartments averaged only 10.5 ± 3.3% and 6.0 ± 1.5% in GL/OL and transverse compartments, respectively relative to uncoated compartments. Fluorescein penetration confirmed selective CaCl2 permeation. Conclusions. These data confirm passive tensile findings of mechanical independence of EOM compartments and extend results to active contraction. EOMs behave actively as if composed of mechanically independent parallel fiber bundles having different insertional targets, consistent with the active pulley and transverse compartmental hypotheses. PMID:25503460

  12. Self-similarity in active colloid motion

    NASA Astrophysics Data System (ADS)

    Constant, Colin; Sukhov, Sergey; Dogariu, Aristide

    The self-similarity of displacements among randomly evolving systems has been used to describe the foraging patterns of animals and predict the growth of financial systems. At micron scales, the motion of colloidal particles can be analyzed by sampling their spatial displacement in time. For self-similar systems in equilibrium, the mean squared displacement increases linearly in time. However, external forces can take the system out of equilibrium, creating active colloidal systems, and making this evolution more complex. A moment scaling spectrum of the distribution of particle displacements quantifies the degree of self-similarity in the colloid motion. We will demonstrate that, by varying the temporal and spatial characteristics of the external forces, one can control the degree of self-similarity in active colloid motion.

  13. HYPOTHESIS TESTING WITH THE SIMILARITY INDEX

    EPA Science Inventory

    Mulltilocus DNA fingerprinting methods have been used extensively to address genetic issues in wildlife populations. Hypotheses concerning population subdivision and differing levels of diversity can be addressed through the use of the similarity index (S), a band-sharing coeffic...

  14. Heat transfer in geometrically similar cylinders

    NASA Technical Reports Server (NTRS)

    Riekert, P; Held, A

    1941-01-01

    The power and heat-stress conditions of geometrically similar engines are discussed. The advantages accruing from smaller cylinder dimensions are higher specific horsepower, lower weight per horsepower, lower piston temperature, and less frontal area, with reduced detonation tendency.

  15. Grand Canyon Similar to Mount Sharp

    NASA Image and Video Library

    2012-08-27

    Before NASA Curiosity rover landed on Mars, the strata exposed in Mount Sharp were compared to those in the Grand Canyon of the western United States, shown here. Scientists are surprised by just how close the similarities are.

  16. Similarities in Becoming: Transsexuals and Adolescents.

    ERIC Educational Resources Information Center

    Fleming, Michael; Feinbloom, Deborah

    1984-01-01

    Discusses the diagnosis of transsexual in terms of its similarities with adolescence. In considering the extreme example of the transsexual, normal adolescent development emerges as more purposive and integrative in the establishment of gender identity. (JAC)

  17. HYPOTHESIS TESTING WITH THE SIMILARITY INDEX

    EPA Science Inventory

    Mulltilocus DNA fingerprinting methods have been used extensively to address genetic issues in wildlife populations. Hypotheses concerning population subdivision and differing levels of diversity can be addressed through the use of the similarity index (S), a band-sharing coeffic...

  18. Comparing methods for single paragraph similarity analysis.

    PubMed

    Stone, Benjamin; Dennis, Simon; Kwantes, Peter J

    2011-01-01

    The focus of this paper is two-fold. First, similarities generated from six semantic models were compared to human ratings of paragraph similarity on two datasets-23 World Entertainment News Network paragraphs and 50 ABC newswire paragraphs. Contrary to findings on smaller textual units such as word associations (Griffiths, Tenenbaum, & Steyvers, 2007), our results suggest that when single paragraphs are compared, simple nonreductive models (word overlap and vector space) can provide better similarity estimates than more complex models (LSA, Topic Model, SpNMF, and CSM). Second, various methods of corpus creation were explored to facilitate the semantic models' similarity estimates. Removing numeric and single characters, and also truncating document length improved performance. Automated construction of smaller Wikipedia-based corpora proved to be very effective, even improving upon the performance of corpora that had been chosen for the domain. Model performance was further improved by augmenting corpora with dataset paragraphs. Copyright © 2010 Cognitive Science Society, Inc.

  19. Bilateral Trade Flows and Income Distribution Similarity

    PubMed Central

    2016-01-01

    Current models of bilateral trade neglect the effects of income distribution. This paper addresses the issue by accounting for non-homothetic consumer preferences and hence investigating the role of income distribution in the context of the gravity model of trade. A theoretically justified gravity model is estimated for disaggregated trade data (Dollar volume is used as dependent variable) using a sample of 104 exporters and 108 importers for 1980–2003 to achieve two main goals. We define and calculate new measures of income distribution similarity and empirically confirm that greater similarity of income distribution between countries implies more trade. Using distribution-based measures as a proxy for demand similarities in gravity models, we find consistent and robust support for the hypothesis that countries with more similar income-distributions trade more with each other. The hypothesis is also confirmed at disaggregated level for differentiated product categories. PMID:27137462

  20. Bilateral Trade Flows and Income Distribution Similarity.

    PubMed

    Martínez-Zarzoso, Inmaculada; Vollmer, Sebastian

    2016-01-01

    Current models of bilateral trade neglect the effects of income distribution. This paper addresses the issue by accounting for non-homothetic consumer preferences and hence investigating the role of income distribution in the context of the gravity model of trade. A theoretically justified gravity model is estimated for disaggregated trade data (Dollar volume is used as dependent variable) using a sample of 104 exporters and 108 importers for 1980-2003 to achieve two main goals. We define and calculate new measures of income distribution similarity and empirically confirm that greater similarity of income distribution between countries implies more trade. Using distribution-based measures as a proxy for demand similarities in gravity models, we find consistent and robust support for the hypothesis that countries with more similar income-distributions trade more with each other. The hypothesis is also confirmed at disaggregated level for differentiated product categories.

  1. Reexamining the phonological similarity effect in immediate serial recall: the roles of type of similarity, category cuing, and item recall.

    PubMed

    Gupta, Prahlad; Lipinski, John; Aktunc, Emrah

    2005-09-01

    Study of the phonological similarity effect (PSE) in immediate serial recall (ISR) has produced a conflicting body of results. Five experiments tested various theoretical ideas that together may help integrate these results. Experiments 1 and 2 tested alternative accounts that explain the effect of phonological similarity on item recall in terms of feature overlap, linguistic structure, or serial order. In each experiment, the participants' ISR was assessed for rhyming, alliterative, and similar nonrhyming/nonalliterative lists. The results were consistent with the predictions of the serial order account, with item recall being higher for rhyming than for alliterative lists and higher for alliterative than for similar nonrhyming/nonalliterative lists. Experiments 3 and 4 showed that these item recall differences are reduced when list items repeat across lists. Experiment 5 employed rhyming and dissimilar one-syllable and two-syllable lists to demonstrate that recall for similar (rhyming) lists can be better than that for dissimilar lists even in a typical ISR task in which words are used, providing a direct reversal of the classic PSE. These and other previously published results are interpreted and integrated within a proposed theoretical framework that offers an account of the PSE.

  2. The Independent Technical Analysis Process

    SciTech Connect

    Duberstein, Corey A.; Ham, Kenneth D.; Dauble, Dennis D.; Johnson, Gary E.

    2007-04-13

    The Bonneville Power Administration (BPA) contracted with the Pacific Northwest National Laboratory (PNNL) to provide technical analytical support for system-wide fish passage information (BPA Project No. 2006-010-00). The goal of this project was to produce rigorous technical analysis products using independent analysts and anonymous peer reviewers. In the past, regional parties have interacted with a single entity, the Fish Passage Center to access the data, analyses, and coordination related to fish passage. This project provided an independent technical source for non-routine fish passage analyses while allowing routine support functions to be performed by other well-qualified entities.

  3. Achieving Full Dynamic Similarity with Small-Scale Wind Turbine Models

    NASA Astrophysics Data System (ADS)

    Miller, Mark; Kiefer, Janik; Westergaard, Carsten; Hultmark, Marcus

    2016-11-01

    Power and thrust data as a function of Reynolds number and Tip Speed Ratio are presented at conditions matching those of a full scale turbine. Such data has traditionally been very difficult to acquire due to the large length-scales of wind turbines, and the limited size of conventional wind tunnels. Ongoing work at Princeton University employs a novel, high-pressure wind tunnel (up to 220 atmospheres of static pressure) which uses air as the working fluid. This facility allows adjustment of the Reynolds number (via the fluid density) independent of the Tip Speed Ratio, up to a Reynolds number (based on chord and velocity at the tip) of over 3 million. Achieving dynamic similarity using this approach implies very high power and thrust loading, which results in mechanical loads greater than 200 times those experienced by a similarly sized model in a conventional wind tunnel. In order to accurately report the power coefficients, a series of tests were carried out on a specially designed model turbine drive-train using an external testing bench to replicate tunnel loading. An accurate map of the drive-train performance at various operating conditions was determined. Finally, subsequent corrections to the power coefficient are discussed in detail. Supported by: National Science Foundation Grant CBET-1435254 (program director Gregory Rorrer).

  4. On distributional assumptions and whitened cosine similarities.

    PubMed

    Loog, Marco

    2008-06-01

    Recently, an interpretation of the whitened cosine similarity measure as a Bayes decision rule was proposed (C. Liu, "The Bayes Decision Rule Induced Similarity Measures,'' IEEE Trans. Pattern Analysis and Machine Intelligence, vol. 29, no. 6, pp. 1086-1090, June 2007. This communication makes the observation that some of the distributional assumptions made to derive this measure are very restrictive and, considered simultaneously, even inconsistent.

  5. Are calanco landforms similar to river basins?

    PubMed

    Caraballo-Arias, N A; Ferro, V

    2017-12-15

    In the past badlands have been often considered as ideal field laboratories for studying landscape evolution because of their geometrical similarity to larger fluvial systems. For a given hydrological process, no scientific proof exists that badlands can be considered a model of river basin prototypes. In this paper the measurements carried out on 45 Sicilian calanchi, a type of badlands that appears as a small-scale hydrographic unit, are used to establish their morphological similarity with river systems whose data are available in the literature. At first the geomorphological similarity is studied by identifying the dimensionless groups, which can assume the same value or a scaled one in a fixed ratio, representing drainage basin shape, stream network and relief properties. Then, for each property, the dimensionless groups are calculated for the investigated calanchi and the river basins and their corresponding scale ratio is evaluated. The applicability of Hack's, Horton's and Melton's laws for establishing similarity criteria is also tested. The developed analysis allows to conclude that a quantitative morphological similarity between calanco landforms and river basins can be established using commonly applied dimensionless groups. In particular, the analysis showed that i) calanchi and river basins have a geometrically similar shape respect to the parameters Rf and Re with a scale factor close to 1, ii) calanchi and river basins are similar respect to the bifurcation and length ratios (λ=1), iii) for the investigated calanchi the Melton number assumes values less than that (0.694) corresponding to the river case and a scale ratio ranging from 0.52 and 0.78 can be used, iv) calanchi and river basins have similar mean relief ratio values (λ=1.13) and v) calanchi present active geomorphic processes and therefore fall in a more juvenile stage with respect to river basins. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Privacy-preserving matching of similar patients.

    PubMed

    Vatsalan, Dinusha; Christen, Peter

    2016-02-01

    The identification of similar entities represented by records in different databases has drawn considerable attention in many application areas, including in the health domain. One important type of entity matching application that is vital for quality healthcare analytics is the identification of similar patients, known as similar patient matching. A key component of identifying similar records is the calculation of similarity of the values in attributes (fields) between these records. Due to increasing privacy and confidentiality concerns, using the actual attribute values of patient records to identify similar records across different organizations is becoming non-trivial because the attributes in such records often contain highly sensitive information such as personal and medical details of patients. Therefore, the matching needs to be based on masked (encoded) values while being effective and efficient to allow matching of large databases. Bloom filter encoding has widely been used as an efficient masking technique for privacy-preserving matching of string and categorical values. However, no work on Bloom filter-based masking of numerical data, such as integer (e.g. age), floating point (e.g. body mass index), and modulus (numbers wrap around upon reaching a certain value, e.g. date and time), which are commonly required in the health domain, has been presented in the literature. We propose a framework with novel methods for masking numerical data using Bloom filters, thereby facilitating the calculation of similarities between records. We conduct an empirical study on publicly available real-world datasets which shows that our framework provides efficient masking and achieves similar matching accuracy compared to the matching of actual unencoded patient records.

  7. Generative Models for Similarity-based Classification

    DTIC Science & Technology

    2007-01-01

    whom the author has granted “the right to reproduce and sell (a) copies of the manuscript in microform and/or (b) printed copies of the manuscript...underlying features may be inaccessible. For example, Chapter 6 discusses a dataset of sonar echoes for which the pairwise similarities are judged by human ...listeners. For this dataset, the putative perceptual features from which the human similarity ratings are generated are unknown – indeed eliciting the

  8. Interpersonal attraction and personality: what is attractive--self similarity, ideal similarity, complementarity or attachment security?

    PubMed

    Klohnen, Eva C; Luo, Shanhong

    2003-10-01

    Little is known about whether personality characteristics influence initial attraction. Because adult attachment differences influence a broad range of relationship processes, the authors examined their role in 3 experimental attraction studies. The authors tested four major attraction hypotheses--self similarity, ideal-self similarity, complementarity, and attachment security--and examined both actual and perceptual factors. Replicated analyses across samples, designs, and manipulations showed that actual security and self similarity predicted attraction. With regard to perceptual factors, ideal similarity, self similarity, and security all were significant predictors. Whereas perceptual ideal and self similarity had incremental predictive power, perceptual security's effects were subsumed by perceptual ideal similarity. Perceptual self similarity fully mediated actual attachment similarity effects, whereas ideal similarity was only a partial mediator.

  9. Similarity searching in large combinatorial chemistry spaces

    NASA Astrophysics Data System (ADS)

    Rarey, Matthias; Stahl, Martin

    2001-06-01

    We present a novel algorithm, called Ftrees-FS, for similarity searching in large chemistry spaces based on dynamic programming. Given a query compound, the algorithm generates sets of compounds from a given chemistry space that are similar to the query. The similarity search is based on the feature tree similarity measure representing molecules by tree structures. This descriptor allows handling combinatorial chemistry spaces as a whole instead of looking at subsets of enumerated compounds. Within few minutes of computing time, the algorithm is able to find the most similar compound in very large spaces as well as sets of compounds at an arbitrary similarity level. In addition, the diversity among the generated compounds can be controlled. A set of 17 000 fragments of known drugs, generated by the RECAP procedure from the World Drug Index, was used as the search chemistry space. These fragments can be combined to more than 1018 compounds of reasonable size. For validation, known antagonists/inhibitors of several targets including dopamine D4, histamine H1, and COX2 are used as queries. Comparison of the compounds created by Ftrees-FS to other known actives demonstrates the ability of the method to jump between structurally unrelated molecule classes.

  10. Predicting Odor Perceptual Similarity from Odor Structure

    PubMed Central

    Weiss, Tali; Frumin, Idan; Khan, Rehan M.; Sobel, Noam

    2013-01-01

    To understand the brain mechanisms of olfaction we must understand the rules that govern the link between odorant structure and odorant perception. Natural odors are in fact mixtures made of many molecules, and there is currently no method to look at the molecular structure of such odorant-mixtures and predict their smell. In three separate experiments, we asked 139 subjects to rate the pairwise perceptual similarity of 64 odorant-mixtures ranging in size from 4 to 43 mono-molecular components. We then tested alternative models to link odorant-mixture structure to odorant-mixture perceptual similarity. Whereas a model that considered each mono-molecular component of a mixture separately provided a poor prediction of mixture similarity, a model that represented the mixture as a single structural vector provided consistent correlations between predicted and actual perceptual similarity (r≥0.49, p<0.001). An optimized version of this model yielded a correlation of r = 0.85 (p<0.001) between predicted and actual mixture similarity. In other words, we developed an algorithm that can look at the molecular structure of two novel odorant-mixtures, and predict their ensuing perceptual similarity. That this goal was attained using a model that considers the mixtures as a single vector is consistent with a synthetic rather than analytical brain processing mechanism in olfaction. PMID:24068899

  11. All-orders Skyrmions

    SciTech Connect

    Marleau, L. )

    1992-03-01

    We consider a special class of Skyrme-like Lagrangians which include higher-order terms in the derivatives of the pion field but leave the degree of the chiral angle equation at 2. Explicit Lagrangians are constructed up to order 24. They are found to be in agreement with a previous conjecture regarding the general form of the static energy density to all orders for the hedgehog solution. In addition, the static energy density gets zero contribution from Lagrangians of order 10, 14, 18, and 22, suggesting that this result extends to all order 4{ital k}+2 for {ital k}{ge}2. We then proceed to prove both conjectures.

  12. Joint reconstruction of PET-MRI by exploiting structural similarity

    NASA Astrophysics Data System (ADS)

    Ehrhardt, Matthias J.; Thielemans, Kris; Pizarro, Luis; Atkinson, David; Ourselin, Sébastien; Hutton, Brian F.; Arridge, Simon R.

    2015-01-01

    Recent advances in technology have enabled the combination of positron emission tomography (PET) with magnetic resonance imaging (MRI). These PET-MRI scanners simultaneously acquire functional PET and anatomical or functional MRI data. As function and anatomy are not independent of one another the images to be reconstructed are likely to have shared structures. We aim to exploit this inherent structural similarity by reconstructing from both modalities in a joint reconstruction framework. The structural similarity between two modalities can be modelled in two different ways: edges are more likely to be at similar positions and/or to have similar orientations. We analyse the diffusion process generated by minimizing priors that encapsulate these different models. It turns out that the class of parallel level set priors always corresponds to anisotropic diffusion which is sometimes forward and sometimes backward diffusion. We perform numerical experiments where we jointly reconstruct from blurred Radon data with Poisson noise (PET) and under-sampled Fourier data with Gaussian noise (MRI). Our results show that both modalities benefit from each other in areas of shared edge information. The joint reconstructions have less artefacts and sharper edges compared to separate reconstructions and the ℓ2-error can be reduced in all of the considered cases of under-sampling.

  13. Correlating human color similarity judgments and colorimetric representations

    NASA Astrophysics Data System (ADS)

    Vertan, Constantin C.; Ciuc, Mihai; Stoica, A.; Zamfir, Marta; Buzuloiu, Vasile V.; Fernandez-Maloigne, Christine

    2003-10-01

    A color similarity test was conducted on the 24 color patches of a Gretag Macbeth color checker. Color similarities were measured either by distances between standard colorimetric representations (such as RGB, Lab or spectral reflectance curves) or by human observer judgments. In each case, the dissimilarity matrix was processed by a classical, metric, multidimensional scaling algorithm, in order to produce a visually-interpretable two-dimensional plot of color dissimilarity. The analysis of the plots produces some interesting conclusions. First, the plots produced by the Lab, RGB and spectral representations exhibit very evident variation axes according to the luminance and basic chromatic differences (red-green, blue-yellow). This behavior (trivial for the Lab representation) suggests that the color similarity measurement by chromatic differences is implicitly embedded in the RGB and spectral representations. The color dissimilarity plots associated to the human judgments (for any individual, as well as for an "average" observer) exhibit a different organization, which mixes hue, saturation and luminance (HSV). According to these plots, the human similarity judgment is not entirely HSV-based. We prove that it is possible to obtain the same color dissimilarity plots if a fuzzy color model is assumed. The fuzzy color model provides similarity coefficients (similarity degrees) between pairs of colors, based on their inter-distance, according to an imposed "color confusion" control parameter, which seems to be relevant for the human vision.

  14. A similarity-based data warehousing environment for medical images.

    PubMed

    Teixeira, Jefferson William; Annibal, Luana Peixoto; Felipe, Joaquim Cezar; Ciferri, Ricardo Rodrigues; Ciferri, Cristina Dutra de Aguiar

    2015-11-01

    A core issue of the decision-making process in the medical field is to support the execution of analytical (OLAP) similarity queries over images in data warehousing environments. In this paper, we focus on this issue. We propose imageDWE, a non-conventional data warehousing environment that enables the storage of intrinsic features taken from medical images in a data warehouse and supports OLAP similarity queries over them. To comply with this goal, we introduce the concept of perceptual layer, which is an abstraction used to represent an image dataset according to a given feature descriptor in order to enable similarity search. Based on this concept, we propose the imageDW, an extended data warehouse with dimension tables specifically designed to support one or more perceptual layers. We also detail how to build an imageDW and how to load image data into it. Furthermore, we show how to process OLAP similarity queries composed of a conventional predicate and a similarity search predicate that encompasses the specification of one or more perceptual layers. Moreover, we introduce an index technique to improve the OLAP query processing over images. We carried out performance tests over a data warehouse environment that consolidated medical images from exams of several modalities. The results demonstrated the feasibility and efficiency of our proposed imageDWE to manage images and to process OLAP similarity queries. The results also demonstrated that the use of the proposed index technique guaranteed a great improvement in query processing.

  15. Understanding similarity of groundwater systems with empirical copulas

    NASA Astrophysics Data System (ADS)

    Haaf, Ezra; Kumar, Rohini; Samaniego, Luis; Barthel, Roland

    2016-04-01

    Within the classification framework for groundwater systems that aims for identifying similarity of hydrogeological systems and transferring information from a well-observed to an ungauged system (Haaf and Barthel, 2015; Haaf and Barthel, 2016), we propose a copula-based method for describing groundwater-systems similarity. Copulas are an emerging method in hydrological sciences that make it possible to model the dependence structure of two groundwater level time series, independently of the effects of their marginal distributions. This study is based on Samaniego et al. (2010), which described an approach calculating dissimilarity measures from bivariate empirical copula densities of streamflow time series. Subsequently, streamflow is predicted in ungauged basins by transferring properties from similar catchments. The proposed approach is innovative because copula-based similarity has not yet been applied to groundwater systems. Here we estimate the pairwise dependence structure of 600 wells in Southern Germany using 10 years of weekly groundwater level observations. Based on these empirical copulas, dissimilarity measures are estimated, such as the copula's lower- and upper corner cumulated probability, copula-based Spearman's rank correlation - as proposed by Samaniego et al. (2010). For the characterization of groundwater systems, copula-based metrics are compared with dissimilarities obtained from precipitation signals corresponding to the presumed area of influence of each groundwater well. This promising approach provides a new tool for advancing similarity-based classification of groundwater system dynamics. Haaf, E., Barthel, R., 2015. Methods for assessing hydrogeological similarity and for classification of groundwater systems on the regional scale, EGU General Assembly 2015, Vienna, Austria. Haaf, E., Barthel, R., 2016. An approach for classification of hydrogeological systems at the regional scale based on groundwater hydrographs EGU General Assembly

  16. Prediction of Drug Indications Based on Chemical Interactions and Chemical Similarities

    PubMed Central

    Huang, Guohua; Lu, Yin; Lu, Changhong; Cai, Yu-Dong

    2015-01-01

    Discovering potential indications of novel or approved drugs is a key step in drug development. Previous computational approaches could be categorized into disease-centric and drug-centric based on the starting point of the issues or small-scaled application and large-scale application according to the diversity of the datasets. Here, a classifier has been constructed to predict the indications of a drug based on the assumption that interactive/associated drugs or drugs with similar structures are more likely to target the same diseases using a large drug indication dataset. To examine the classifier, it was conducted on a dataset with 1,573 drugs retrieved from Comprehensive Medicinal Chemistry database for five times, evaluated by 5-fold cross-validation, yielding five 1st order prediction accuracies that were all approximately 51.48%. Meanwhile, the model yielded an accuracy rate of 50.00% for the 1st order prediction by independent test on a dataset with 32 other drugs in which drug repositioning has been confirmed. Interestingly, some clinically repurposed drug indications that were not included in the datasets are successfully identified by our method. These results suggest that our method may become a useful tool to associate novel molecules with new indications or alternative indications with existing drugs. PMID:25821813

  17. Self-similar Turing patterns: An anomalous diffusion consequence.

    PubMed

    Hernández, D; Herrera-Hernández, E C; Núñez-López, M; Hernández-Coronado, H

    2017-02-01

    In this work, we show that under specific anomalous diffusion conditions, chemical systems can produce well-ordered self-similar concentration patterns through diffusion-driven instability. We also find spiral patterns and patterns with mixtures of rotational symmetries. The type of anomalous diffusion discussed in this work, either subdiffusion or superdiffusion, is a consequence of the medium heterogeneity, and it is modeled through a space-dependent diffusion coefficient with a power-law functional form.

  18. Self-similar Turing patterns: An anomalous diffusion consequence

    NASA Astrophysics Data System (ADS)

    Hernández, D.; Herrera-Hernández, E. C.; Núñez-López, M.; Hernández-Coronado, H.

    2017-02-01

    In this work, we show that under specific anomalous diffusion conditions, chemical systems can produce well-ordered self-similar concentration patterns through diffusion-driven instability. We also find spiral patterns and patterns with mixtures of rotational symmetries. The type of anomalous diffusion discussed in this work, either subdiffusion or superdiffusion, is a consequence of the medium heterogeneity, and it is modeled through a space-dependent diffusion coefficient with a power-law functional form.

  19. Analog optoelectronic independent component analysis for radio frequency signals

    NASA Astrophysics Data System (ADS)

    Baylor, Martha-Elizabeth

    This thesis addresses the problem of blind source separation of signals at radio frequencies. Independent component analysis (ICA), which includes a second-order decorrelation followed by a fourth-order decorrelation, uses signal independence to estimate the original signals from the received mixtures. Until now, ICA has been applied to many applications at or below audio frequencies. The work presented here demonstrates that an optoelectronic implementation using the parallel processing nature of dynamic holography can overcome the computational difficulties associated with algorithmic implementations of ICA. The holographic nature of a photorefractive crystal combined with the non-linearity of an electro-optic modulator in a feedback loop can be described by a nonlinear dynamical equation. The dynamics can be cast in the form of Lotka-Volterra equations used to study the dynamics of competing populations of species. Although this analogy with the animal world is interesting, the dynamical equation associated with the fourth-order decorrelation system is fascinating. The statistics associated with the original signals, rather than an external potential, determine the dynamics of the system. In particular, the system is multistable, metastable, or monostable depending on whether the probability density functions of the original signals are sub-Gaussian, Gaussian, or super-Gaussian, respectively. The multistable solution, which occurs for sub-Gaussian signals, provides the winner-takes-all behavior required to separate signals. This ability to separate sub-Gaussian signals is advantageous since signals modulated on a sinusoidal carrier are sub-Gaussian. The fourth-order decorrelation system achieves greater than 40 dB signal separation on 200 MHz single-frequency sine waves and greater than 20 dB signal separation for 10 MHz bandwidth signals. The system performance is degraded by 10 to 20 dB when mixed electronically due to imperfections in the mixing circuitry

  20. Dimension independence in exterior algebra.

    PubMed

    Hawrylycz, M

    1995-03-14

    The identities between homogeneous expressions in rank 1 vectors and rank n - 1 covectors in a Grassmann-Cayley algebra of rank n, in which one set occurs multilinearly, are shown to represent a set of dimension-independent identities. The theorem yields an infinite set of nontrivial geometric identities from a given identity.

  1. Will Independent Junior Colleges Survive?

    ERIC Educational Resources Information Center

    Blai, Boris, Jr.

    This essay reviews the current status of private independent junior colleges in the United States. Several studies and innovative programs are cited. Because private junior colleges face shrinking enrollments and diminished funding for instruction, services, and activities, they must now stress cost-effectiveness and practical financial management…

  2. Scales of Independent Behavior (SIB).

    ERIC Educational Resources Information Center

    Thomas, Paulette J.

    1990-01-01

    Designed for use with individuals ages 3 months to 44 years, the Scales of Independent Behavior (SIB) measure adaptive behavior and problem behaviors in such areas as motor skills, social interaction, language, personal self-care, punctuality, destructiveness, and inattention. This paper describes the SIB's administration, scoring,…

  3. Scales of Independent Behavior (SIB).

    ERIC Educational Resources Information Center

    Thomas, Paulette J.

    1990-01-01

    Designed for use with individuals ages 3 months to 44 years, the Scales of Independent Behavior (SIB) measure adaptive behavior and problem behaviors in such areas as motor skills, social interaction, language, personal self-care, punctuality, destructiveness, and inattention. This paper describes the SIB's administration, scoring,…

  4. Independent Study Course Development Costs.

    ERIC Educational Resources Information Center

    Wright, Clayton R.

    1988-01-01

    Discusses actual costs for developing independent study print courses for use in learning centers or for distance delivery, and presents a resource allocation guideline based on figures from Grant MacEwan Community College (Alberta). Topics discussed include the course writer/developer, clerical support, copyright clearance, instructional design,…

  5. Field Independence: Reviewing the Evidence

    ERIC Educational Resources Information Center

    Evans, Carol; Richardson, John T. E.; Waring, Michael

    2013-01-01

    Background: The construct of ?eld independence (FI) remains one of the most widely cited notions in research on cognitive style and on learning and instruction more generally. However, a great deal of confusion continues to exist around the de?nition of FI, its measurement, and the interpretation of research results, all of which have served to…

  6. Independent Study Project, Topic: Topology.

    ERIC Educational Resources Information Center

    Notre Dame High School, Easton, PA.

    Using this guide and the four popular books noted in it, a student, working independently, will learn about some of the classical ideas and problems of topology: the Meobius strip and Klein bottle, the four color problem, genus of a surface, networks, Euler's formula, and the Jordan Curve Theorem. The unit culminates in a project of the students'…

  7. Boston: Cradle of American Independence

    ERIC Educational Resources Information Center

    Community College Journal, 2004

    2004-01-01

    The 2005 American Association of Community Colleges Annual Convention will be held April 6-9 in Boston. While thoroughly modern, the iconic city's identity is firmly rooted in the past. As the cradle of American independence, Boston's long history is an integral part of the American fabric. Adams, Revere, Hancock are more than historical figures;…

  8. Field Independence: Reviewing the Evidence

    ERIC Educational Resources Information Center

    Evans, Carol; Richardson, John T. E.; Waring, Michael

    2013-01-01

    Background: The construct of ?eld independence (FI) remains one of the most widely cited notions in research on cognitive style and on learning and instruction more generally. However, a great deal of confusion continues to exist around the de?nition of FI, its measurement, and the interpretation of research results, all of which have served to…

  9. Boston: Cradle of American Independence

    ERIC Educational Resources Information Center

    Community College Journal, 2004

    2004-01-01

    The 2005 American Association of Community Colleges Annual Convention will be held April 6-9 in Boston. While thoroughly modern, the iconic city's identity is firmly rooted in the past. As the cradle of American independence, Boston's long history is an integral part of the American fabric. Adams, Revere, Hancock are more than historical figures;…

  10. Dimension independence in exterior algebra.

    PubMed Central

    Hawrylycz, M

    1995-01-01

    The identities between homogeneous expressions in rank 1 vectors and rank n - 1 covectors in a Grassmann-Cayley algebra of rank n, in which one set occurs multilinearly, are shown to represent a set of dimension-independent identities. The theorem yields an infinite set of nontrivial geometric identities from a given identity. PMID:11607520

  11. Characteristics of Independent Music Teachers

    ERIC Educational Resources Information Center

    Upitis, Rena; Abrami, Philip C.; Brook, Julia; Boese, Karen; King, Matthew

    2017-01-01

    The purpose of the present study was to learn about the characteristics of independent music teachers, their beliefs about music teaching, and their studio practices. A self-report survey included questions about the teachers' (a) background experiences, (b) pedagogical approaches, (c) use of digital technologies, and (d) professional development…

  12. Content Independence in Multimedia Databases.

    ERIC Educational Resources Information Center

    de Vries, Arjen P.

    2001-01-01

    Investigates the role of data management in multimedia digital libraries, and its implications for the design of database management systems. Introduces the notions of content abstraction and content independence. Proposes a blueprint of a new class of database technology, which supports the basic functionality for the management of both content…

  13. Haptic Tracking Permits Bimanual Independence

    ERIC Educational Resources Information Center

    Rosenbaum, David A.; Dawson, Amanda A.; Challis, John H.

    2006-01-01

    This study shows that in a novel task--bimanual haptic tracking--neurologically normal human adults can move their 2 hands independently for extended periods of time with little or no training. Participants lightly touched buttons whose positions were moved either quasi-randomly in the horizontal plane by 1 or 2 human drivers (Experiment 1), in…

  14. Minority Leaders for Independent Schools.

    ERIC Educational Resources Information Center

    Kahn, Bobette Reed; Dandridge, William L.

    This booklet addresses minority group teachers and teacher candidates and provides information on the career opportunities that are available in independent elementary and secondary schools. A brief description of private schools includes notes on how they differ from public schools in governance, finances, curriculum, and student and faculty…

  15. Semantic similarity between ontologies at different scales

    SciTech Connect

    Zhang, Qingpeng; Haglin, David J.

    2016-04-01

    In the past decade, existing and new knowledge and datasets has been encoded in different ontologies for semantic web and biomedical research. The size of ontologies is often very large in terms of number of concepts and relationships, which makes the analysis of ontologies and the represented knowledge graph computational and time consuming. As the ontologies of various semantic web and biomedical applications usually show explicit hierarchical structures, it is interesting to explore the trade-offs between ontological scales and preservation/precision of results when we analyze ontologies. This paper presents the first effort of examining the capability of this idea via studying the relationship between scaling biomedical ontologies at different levels and the semantic similarity values. We evaluate the semantic similarity between three Gene Ontology slims (Plant, Yeast, and Candida, among which the latter two belong to the same kingdom—Fungi) using four popular measures commonly applied to biomedical ontologies (Resnik, Lin, Jiang-Conrath, and SimRel). The results of this study demonstrate that with proper selection of scaling levels and similarity measures, we can significantly reduce the size of ontologies without losing substantial detail. In particular, the performance of Jiang-Conrath and Lin are more reliable and stable than that of the other two in this experiment, as proven by (a) consistently showing that Yeast and Candida are more similar (as compared to Plant) at different scales, and (b) small deviations of the similarity values after excluding a majority of nodes from several lower scales. This study provides a deeper understanding of the application of semantic similarity to biomedical ontologies, and shed light on how to choose appropriate semantic similarity measures for biomedical engineering.

  16. A residual stress study in similar and dissimilar welds

    DOE PAGES

    Eisazadeh, Hamid; Goldak, John A.; Aidun, Daryush K.; ...

    2016-04-01

    Residual strain distributions in similar and dissimilar welds were measured using neutron diffraction (ND) method. Then, using three strain components, three-dimensional stress states were calculated. The results were used to determine the effect of the martensitic phase transformation and material properties on residual stress (RS) distribution. It was observed that smaller longitudinal RS was induced in the low carbon steel side of dissimilar weld when compared to its similar weld. Also, it was found that the transverse RS near and within the weld zone (WZ) in dissimilar weld exhibited a distinctive trend, with tensile mode reaching the yield strength ofmore » the base metal (BM). In order to characterize the WZ in dissimilar weld, we deployed optical microscopy, hardness, and energy dispersive X-ray spectroscopy (EDAX). This study not only provides further insight into the RS state in similar and dissimilar welds; it also delivers important consequences of phase transformation in the latter case.« less

  17. A residual stress study in similar and dissimilar welds

    SciTech Connect

    Eisazadeh, Hamid; Goldak, John A.; Aidun, Daryush K.; Coules, Harry E.; Bunn, Jeffrey R; Achuthan, A.

    2016-04-01

    Residual strain distributions in similar and dissimilar welds were measured using neutron diffraction (ND) method. Then, using three strain components, three-dimensional stress states were calculated. The results were used to determine the effect of the martensitic phase transformation and material properties on residual stress (RS) distribution. It was observed that smaller longitudinal RS was induced in the low carbon steel side of dissimilar weld when compared to its similar weld. Also, it was found that the transverse RS near and within the weld zone (WZ) in dissimilar weld exhibited a distinctive trend, with tensile mode reaching the yield strength of the base metal (BM). In order to characterize the WZ in dissimilar weld, we deployed optical microscopy, hardness, and energy dispersive X-ray spectroscopy (EDAX). This study not only provides further insight into the RS state in similar and dissimilar welds; it also delivers important consequences of phase transformation in the latter case.

  18. Statistical considerations for confirmatory clinical trials for similar biotherapeutic products.

    PubMed

    Njue, Catherine

    2011-09-01

    For the purpose of comparing the efficacy and safety of a Similar Biotherapeutic Product (SBP) to a Reference Biotherapeutic Product (RBP), the "Guidelines on Evaluation of Similar Biotherapeutic Products (SBPs)" issued by the World Health Organisation (WHO), states that equivalence or non-inferiority studies may be acceptable. While in principle, equivalence trials are preferred, non-inferiority trials may be considered if appropriately justified, such as for a medicinal product with a wide safety margin. However, the statistical issues involved in the design, conduct, analysis and interpretation of equivalence and non-inferiority trials are complex and subtle, and require that all aspects of these trials be given careful consideration. These issues are important in order to ensure that equivalence and non-inferiority trials provide valid data that are necessary to draw reliable conclusions regarding the clinical similarity of an SBP to an RBP. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  19. Activity-relevant similarity values for fingerprints and implications for similarity searching

    PubMed Central

    Jasial, Swarit; Hu, Ye; Vogt, Martin; Bajorath, Jürgen

    2016-01-01

    A largely unsolved problem in chemoinformatics is the issue of how calculated compound similarity relates to activity similarity, which is central to many applications. In general, activity relationships are predicted from calculated similarity values. However, there is no solid scientific foundation to bridge between calculated molecular and observed activity similarity. Accordingly, the success rate of identifying new active compounds by similarity searching is limited. Although various attempts have been made to establish relationships between calculated fingerprint similarity values and biological activities, none of these has yielded generally applicable rules for similarity searching. In this study, we have addressed the question of molecular versus activity similarity in a more fundamental way. First, we have evaluated if activity-relevant similarity value ranges could in principle be identified for standard fingerprints and distinguished from similarity resulting from random compound comparisons. Then, we have analyzed if activity-relevant similarity values could be used to guide typical similarity search calculations aiming to identify active compounds in databases. It was found that activity-relevant similarity values can be identified as a characteristic feature of fingerprints. However, it was also shown that such values cannot be reliably used as thresholds for practical similarity search calculations. In addition, the analysis presented herein helped to rationalize differences in fingerprint search performance. PMID:27127620

  20. Earthquake detection through computationally efficient similarity search.

    PubMed

    Yoon, Clara E; O'Reilly, Ossian; Bergen, Karianne J; Beroza, Gregory C

    2015-12-01

    Seismology is experiencing rapid growth in the quantity of data, which has outpaced the development of processing algorithms. Earthquake detection-identification of seismic events in continuous data-is a fundamental operation for observational seismology. We developed an efficient method to detect earthquakes using waveform similarity that overcomes the disadvantages of existing detection methods. Our method, called Fingerprint And Similarity Thresholding (FAST), can analyze a week of continuous seismic waveform data in less than 2 hours, or 140 times faster than autocorrelation. FAST adapts a data mining algorithm, originally designed to identify similar audio clips within large databases; it first creates compact "fingerprints" of waveforms by extracting key discriminative features, then groups similar fingerprints together within a database to facilitate fast, scalable search for similar fingerprint pairs, and finally generates a list of earthquake detections. FAST detected most (21 of 24) cataloged earthquakes and 68 uncataloged earthquakes in 1 week of continuous data from a station located near the Calaveras Fault in central California, achieving detection performance comparable to that of autocorrelation, with some additional false detections. FAST is expected to realize its full potential when applied to extremely long duration data sets over a distributed network of seismic stations. The widespread application of FAST has the potential to aid in the discovery of unexpected seismic signals, improve seismic monitoring, and promote a greater understanding of a variety of earthquake processes.

  1. Earthquake detection through computationally efficient similarity search

    PubMed Central

    Yoon, Clara E.; O’Reilly, Ossian; Bergen, Karianne J.; Beroza, Gregory C.

    2015-01-01

    Seismology is experiencing rapid growth in the quantity of data, which has outpaced the development of processing algorithms. Earthquake detection—identification of seismic events in continuous data—is a fundamental operation for observational seismology. We developed an efficient method to detect earthquakes using waveform similarity that overcomes the disadvantages of existing detection methods. Our method, called Fingerprint And Similarity Thresholding (FAST), can analyze a week of continuous seismic waveform data in less than 2 hours, or 140 times faster than autocorrelation. FAST adapts a data mining algorithm, originally designed to identify similar audio clips within large databases; it first creates compact “fingerprints” of waveforms by extracting key discriminative features, then groups similar fingerprints together within a database to facilitate fast, scalable search for similar fingerprint pairs, and finally generates a list of earthquake detections. FAST detected most (21 of 24) cataloged earthquakes and 68 uncataloged earthquakes in 1 week of continuous data from a station located near the Calaveras Fault in central California, achieving detection performance comparable to that of autocorrelation, with some additional false detections. FAST is expected to realize its full potential when applied to extremely long duration data sets over a distributed network of seismic stations. The widespread application of FAST has the potential to aid in the discovery of unexpected seismic signals, improve seismic monitoring, and promote a greater understanding of a variety of earthquake processes. PMID:26665176

  2. Evaluating protein similarity from coarse structures.

    PubMed

    Wang, Yong; Wu, Ling-Yun; Zhang, Ji-Hong; Zhan, Zhong-Wei; Zhang, Xiang-Sun; Chen, Luonan

    2009-01-01

    To unscramble the relationship between protein function and protein structure, it is essential to assess the protein similarity from different aspects. Although many methods have been proposed for protein structure alignment or comparison, alternative similarity measures are still strongly demanded due to the requirement of fast screening and query in large-scale structure databases. In this paper, we first formulate a novel representation of a protein structure, i.e., Feature Sequence of Surface (FSS). Then, a new score scheme is developed to measure the similarity between two representations. To verify the proposed method, numerical experiments are conducted in four different protein data sets. We also classify SARS coronavirus to verify the effectiveness of the new method. Furthermore, preliminary results of fast classification of the whole CATH v2.5.1 database based on the new macrostructure similarity are given as a pilot study. We demonstrate that the proposed approach to measure the similarities between protein structures is simple to implement, computationally efficient, and surprisingly fast. In addition, the method itself provides a new and quantitative tool to view a protein structure.

  3. Quantifying visual similarity in clinical iconic graphics.

    PubMed

    Payne, Philip R O; Starren, Justin B

    2005-01-01

    The use of icons and other graphical components in user interfaces has become nearly ubiquitous. The interpretation of such icons is based on the assumption that different users perceive the shapes similarly. At the most basic level, different users must agree on which shapes are similar and which are different. If this similarity can be measured, it may be usable as the basis to design better icons. The purpose of this study was to evaluate a novel method for categorizing the visual similarity of graphical primitives, called Presentation Discovery, in the domain of mammography. Six domain experts were given 50 common textual mammography findings and asked to draw how they would represent those findings graphically. Nondomain experts sorted the resulting graphics into groups based on their visual characteristics. The resulting groups were then analyzed using traditional statistics and hypothesis discovery tools. Strength of agreement was evaluated using computational simulations of sorting behavior. Sorter agreement was measured at both the individual graphical and concept-group levels using a novel simulation-based method. "Consensus clusters" of graphics were derived using a hierarchical clustering algorithm. The multiple sorters were able to reliably group graphics into similar groups that strongly correlated with underlying domain concepts. Visual inspection of the resulting consensus clusters indicated that graphical primitives that could be informative in the design of icons were present. The method described provides a rigorous alternative to intuitive design processes frequently employed in the design of icons and other graphical interface components.

  4. Predicting missing links via structural similarity

    NASA Astrophysics Data System (ADS)

    Lyu, Guo-Dong; Fan, Chang-Jun; Yu, Lian-Fei; Xiu, Bao-Xin; Zhang, Wei-Ming

    2015-04-01

    Predicting missing links in networks plays a significant role in modern science. On the basis of structural similarity, our paper proposes a new node-similarity-based measure called biased resource allocation (BRA), which is motivated by the resource allocation (RA) measure. Comparisons between BRA and nine well-known node-similarity-based measures on five real networks indicate that BRA performs no worse than RA, which was the best node-similarity-based index in previous researches. Afterwards, based on localPath (LP) and Katz measure, we propose another two improved measures, named Im-LocalPath and Im-Katz respectively. Numerical results show that the prediction accuracy of both Im-LP and Im-Katz measure improve compared with the original LP and Katz measure. Finally, a new path-similarity-based measure and its improved measure, called LYU and Im-LYU measure, are proposed and especially, Im-LYU measure is shown to perform more remarkably than other mentioned measures.

  5. Geometric similarity between protein-RNA interfaces.

    PubMed

    Zhou, Peng; Zou, Jianwei; Tian, Feifei; Shang, Zhicai

    2009-12-01

    A new method is described to measure the geometric similarity between protein-RNA interfaces quantitatively. The method is based on a procedure that dissects the interface geometry in terms of the spatial relationships between individual amino acid nucleotide pairs. Using this technique, we performed an all-on-all comparison of 586 protein-RNA interfaces deposited in the current Protein Data Bank, as the result, an interface-interface similarity score matrix was obtained. Based upon this matrix, hierarchical clustering was carried out which yielded a complete clustering tree for the 586 protein-RNA interfaces. By investigating the organizing behavior of the clustering tree and the SCOP classification of protein partners in complexes, a geometrically nonredundant, diverse data set (representative data set) consisting of 45 distinct protein-RNA interfaces was extracted for the purpose of studying protein-RNA interactions, RNA regulations, and drug design. We classified protein-RNA interfaces into three types. In type I, the families and interface structural classes of the protein partners, as well as the interface geometries are all similar. In type II, the interface geometries and the interface structural classes are similar, whereas the protein families are different. In type III, only the interface geometries are similar but the protein families and the interface structural classes are distinct. Furthermore, we also show two new RNA recognition themes derived from the representative data set.

  6. Efficient Video Similarity Measurement and Search

    SciTech Connect

    Cheung, Sen-ching S.

    2002-12-19

    The amount of information on the world wide web has grown enormously since its creation in 1990. Duplication of content is inevitable because there is no central management on the web. Studies have shown that many similar versions of the same text documents can be found throughout the web. This redundancy problem is more severe for multimedia content such as web video sequences, as they are often stored in multiple locations and different formats to facilitate downloading and streaming. Similar versions of the same video can also be found, unknown to content creators, when web users modify and republish original content using video editing tools. Identifying similar content can benefit many web applications and content owners. For example, it will reduce the number of similar answers to a web search and identify inappropriate use of copyright content. In this dissertation, they present a system architecture and corresponding algorithms to efficiently measure, search, and organize similar video sequences found on any large database such as the web.

  7. Self-Similar Compressible Free Vortices

    NASA Technical Reports Server (NTRS)

    vonEllenrieder, Karl

    1998-01-01

    Lie group methods are used to find both exact and numerical similarity solutions for compressible perturbations to all incompressible, two-dimensional, axisymmetric vortex reference flow. The reference flow vorticity satisfies an eigenvalue problem for which the solutions are a set of two-dimensional, self-similar, incompressible vortices. These solutions are augmented by deriving a conserved quantity for each eigenvalue, and identifying a Lie group which leaves the reference flow equations invariant. The partial differential equations governing the compressible perturbations to these reference flows are also invariant under the action of the same group. The similarity variables found with this group are used to determine the decay rates of the velocities and thermodynamic variables in the self-similar flows, and to reduce the governing partial differential equations to a set of ordinary differential equations. The ODE's are solved analytically and numerically for a Taylor vortex reference flow, and numerically for an Oseen vortex reference flow. The solutions are used to examine the dependencies of the temperature, density, entropy, dissipation and radial velocity on the Prandtl number. Also, experimental data on compressible free vortex flow are compared to the analytical results, the evolution of vortices from initial states which are not self-similar is discussed, and the energy transfer in a slightly-compressible vortex is considered.

  8. Background Independence and Duality Invariance in String Theory.

    PubMed

    Hohm, Olaf

    2017-03-31

    Closed string theory exhibits an O(D,D) duality symmetry on tori, which in double field theory is manifest before compactification. I prove that to first order in α^{'} there is no manifestly background independent and duality invariant formulation of bosonic string theory in terms of a metric, b field, and dilaton. To this end I use O(D,D) invariant second order perturbation theory around flat space to show that the unique background independent candidate expression for the gauge algebra at order α^{'} is inconsistent with the Jacobi identity. A background independent formulation exists instead for frame variables subject to α^{'}-deformed frame transformations (generalized Green-Schwarz transformations). Potential applications for curved backgrounds, as in cosmology, are discussed.

  9. Background Independence and Duality Invariance in String Theory

    NASA Astrophysics Data System (ADS)

    Hohm, Olaf

    2017-03-01

    Closed string theory exhibits an O (D ,D ) duality symmetry on tori, which in double field theory is manifest before compactification. I prove that to first order in α' there is no manifestly background independent and duality invariant formulation of bosonic string theory in terms of a metric, b field, and dilaton. To this end I use O (D ,D ) invariant second order perturbation theory around flat space to show that the unique background independent candidate expression for the gauge algebra at order α' is inconsistent with the Jacobi identity. A background independent formulation exists instead for frame variables subject to α'-deformed frame transformations (generalized Green-Schwarz transformations). Potential applications for curved backgrounds, as in cosmology, are discussed.

  10. Symbols of a cosmic order

    NASA Astrophysics Data System (ADS)

    Madjid, F. Hadi; Myers, John M.

    2016-10-01

    The world runs on networks over which signals communicate sequences of symbols, e.g. numerals. Examining both engineered and natural communications networks reveals an unsuspected order that depends on contact with an unpredictable entity. This order has three roots. The first is a proof within quantum theory that no evidence can ever determine its explanation, so that an agent choosing an explanation must do so unpredictably. The second root is the showing that clocks that step computers do not "tell time" but serve as self-adjusting symbol-handling agents that regulate "logically synchronized" motion in response to unpredictable disturbances. Such a clock-agent has a certain independence as well as the capacity to communicate via unpredictable symbols with other clock-agents and to adjust its own tick rate in response to that communication. The third root is the noticing of unpredictable symbol exchange in natural systems, including the transmission of symbols found in molecular biology. We introduce a symbol-handling agent as a role played in some cases by a person, for example a physicist who chooses an explanation of given experimental outcomes, and in other cases by some other biological entity, and in still other cases by an inanimate device, such as a computer-based detector used in physical measurements. While we forbear to try to explain the propensity of agents at all levels from cells to civilizations to form and operate networks of logically synchronized symbol-handling agents, we point to this propensity as an overlooked cosmic order, an order structured by the unpredictability ensuing from the proof. Appreciating the cosmic order leads to a conception of agency that replaces volition by unpredictability and reconceives the notion of objectivity in a way that makes a place for agency in the world as described by physics. Some specific implications for physics are outlined.

  11. Similarity issues of confluence of fuzzy relations

    NASA Astrophysics Data System (ADS)

    Kuhr, Tomas; Vychodil, Vilem

    2012-04-01

    We study similarity issues of confluence and related properties of fuzzy relations. The ordinary notions of divergence, convergence, convertibility, and confluence are essential properties of relations which appear in abstract rewriting systems. In a graded setting, we can introduce analogous notions related to the idea of approximate rewriting. This paper is a continuation of our previous paper (Belohlavek et al. 2010), where we have introduced such notions using residuated structures of truth degrees, leaving the ordinary notions a particular case when the underlying structure of truth degrees is the two-valued Boolean algebra. In this paper, we focus on similarity issues of confluence and present formulas which provide approximations of degrees of confluence and related properties based on similarity of the original fuzzy relations.

  12. Multiple ordering in magnetite.

    NASA Technical Reports Server (NTRS)

    Cullen, J. R.; Callen, E. R.

    1973-01-01

    Results of a self-consistent band calculation of the ground-state energy and charge orderings based on a tight-binding scheme in magnetite are presented. They show that below a critical (about 2.2) value of the ratio of interatomic Coulomb energy to bandwidth the lowest energy state has no order. Between this critical value and 2.5, the preferred state is multiply ordered.

  13. Ordering in Conformal Crystals

    NASA Astrophysics Data System (ADS)

    Soni, Vishal; Gomez, Leopoldo; Irvine, William

    2014-03-01

    Condensed matter systems commonly undergo ordering processes that are frustrated by geometric constraints. Experiments on interfacial colloidal systems have resulted in several recent insights into the two dimensional ordering of crystalline lattices frustrated by Gaussian curvature. We study the ordering of flat colloidal Wigner crystals immersed in an axially symmetric potential. By relating the resulting inhomogenous structure to a lattice with Gaussian curvature, we investigate the role of topological defects in organizing the conformal crystal-like ground state.

  14. Multiple ordering in magnetite.

    NASA Technical Reports Server (NTRS)

    Cullen, J. R.; Callen, E. R.

    1973-01-01

    Results of a self-consistent band calculation of the ground-state energy and charge orderings based on a tight-binding scheme in magnetite are presented. They show that below a critical (about 2.2) value of the ratio of interatomic Coulomb energy to bandwidth the lowest energy state has no order. Between this critical value and 2.5, the preferred state is multiply ordered.

  15. Quantifying the similarity of seismic polarizations

    NASA Astrophysics Data System (ADS)

    Jones, Joshua P.; Eaton, David W.; Caffagni, Enrico

    2016-02-01

    Assessing the similarities of seismic attributes can help identify tremor, low signal-to-noise (S/N) signals and converted or reflected phases, in addition to diagnosing site noise and sensor misalignment in arrays. Polarization analysis is a widely accepted method for studying the orientation and directional characteristics of seismic phases via computed attributes, but similarity is ordinarily discussed using qualitative comparisons with reference values or known seismic sources. Here we introduce a technique for quantitative polarization similarity that uses weighted histograms computed in short, overlapping time windows, drawing on methods adapted from the image processing and computer vision literature. Our method accounts for ambiguity in azimuth and incidence angle and variations in S/N ratio. Measuring polarization similarity allows easy identification of site noise and sensor misalignment and can help identify coherent noise and emergent or low S/N phase arrivals. Dissimilar azimuths during phase arrivals indicate misaligned horizontal components, dissimilar incidence angles during phase arrivals indicate misaligned vertical components and dissimilar linear polarization may indicate a secondary noise source. Using records of the Mw = 8.3 Sea of Okhotsk earthquake, from Canadian National Seismic Network broad-band sensors in British Columbia and Yukon Territory, Canada, and a vertical borehole array at Hoadley gas field, central Alberta, Canada, we demonstrate that our method is robust to station spacing. Discrete wavelet analysis extends polarization similarity to the time-frequency domain in a straightforward way. Time-frequency polarization similarities of borehole data suggest that a coherent noise source may have persisted above 8 Hz several months after peak resource extraction from a `flowback' type hydraulic fracture.

  16. Inferring Trust Based on Similarity with TILLIT

    NASA Astrophysics Data System (ADS)

    Tavakolifard, Mozhgan; Herrmann, Peter; Knapskog, Svein J.

    A network of people having established trust relations and a model for propagation of related trust scores are fundamental building blocks in many of today’s most successful e-commerce and recommendation systems. However, the web of trust is often too sparse to predict trust values between non-familiar people with high accuracy. Trust inferences are transitive associations among users in the context of an underlying social network and may provide additional information to alleviate the consequences of the sparsity and possible cold-start problems. Such approaches are helpful, provided that a complete trust path exists between the two users. An alternative approach to the problem is advocated in this paper. Based on collaborative filtering one can exploit the like-mindedness resp. similarity of individuals to infer trust to yet unknown parties which increases the trust relations in the web. For instance, if one knows that with respect to a specific property, two parties are trusted alike by a large number of different trusters, one can assume that they are similar. Thus, if one has a certain degree of trust to the one party, one can safely assume a very similar trustworthiness of the other one. In an attempt to provide high quality recommendations and proper initial trust values even when no complete trust propagation path or user profile exists, we propose TILLIT — a model based on combination of trust inferences and user similarity. The similarity is derived from the structure of the trust graph and users’ trust behavior as opposed to other collaborative-filtering based approaches which use ratings of items or user’s profile. We describe an algorithm realizing the approach based on a combination of trust inferences and user similarity, and validate the algorithm using a real large-scale data-set.

  17. The collagenous gastroenteritides: similarities and differences.

    PubMed

    Gopal, Purva; McKenna, Barbara J

    2010-10-01

    Collagenous gastritis, collagenous sprue, and collagenous colitis share striking histologic similarities and occur together in some patients. They also share some drug and disease associations. Pediatric cases of collagenous gastritis, however, lack most of these associations. The etiologies of the collagenous gastroenteritides are not known, so it is not clear whether they are similar because they share pathogeneses, or because they indicate a common histologic response to varying injuries. The features, disease and drug associations, and the inquiries into the pathogenesis of these disorders are reviewed.

  18. Random walks with similar transition probabilities

    NASA Astrophysics Data System (ADS)

    Schiefermayr, Klaus

    2003-04-01

    We consider random walks on the nonnegative integers with a possible absorbing state at -1. A random walk is called [alpha]-similar to a random walk if there exist constants Cij such that for the corresponding n-step transition probabilities , i,j[greater-or-equal, slanted]0, hold. We give necessary and sufficient conditions for the [alpha]-similarity of two random walks both in terms of the parameters and in terms of the corresponding spectral measures which appear in the spectral representation of the n-step transition probabilities developed by Karlin and McGregor.

  19. Molecular fingerprint similarity search in virtual screening.

    PubMed

    Cereto-Massagué, Adrià; Ojeda, María José; Valls, Cristina; Mulero, Miquel; Garcia-Vallvé, Santiago; Pujadas, Gerard

    2015-01-01

    Molecular fingerprints have been used for a long time now in drug discovery and virtual screening. Their ease of use (requiring little to no configuration) and the speed at which substructure and similarity searches can be performed with them - paired with a virtual screening performance similar to other more complex methods - is the reason for their popularity. However, there are many types of fingerprints, each representing a different aspect of the molecule, which can greatly affect search performance. This review focuses on commonly used fingerprint algorithms, their usage in virtual screening, and the software packages and online tools that provide these algorithms.

  20. Similarity Based Semantic Web Service Match

    NASA Astrophysics Data System (ADS)

    Peng, Hui; Niu, Wenjia; Huang, Ronghuai

    Semantic web service discovery aims at returning the most matching advertised services to the service requester by comparing the semantic of the request service with an advertised service. The semantic of a web service are described in terms of inputs, outputs, preconditions and results in Ontology Web Language for Service (OWL-S) which formalized by W3C. In this paper we proposed an algorithm to calculate the semantic similarity of two services by weighted averaging their inputs and outputs similarities. Case study and applications show the effectiveness of our algorithm in service match.

  1. Some more similarities between Peirce and Skinner

    PubMed Central

    Moxley, Roy A.

    2002-01-01

    C. S. Peirce is noted for pioneering a variety of views, and the case is made here for the similarities and parallels between his views and B. F. Skinner's radical behaviorism. In addition to parallels previously noted, these similarities include an advancement of experimental science, a behavioral psychology, a shift from nominalism to realism, an opposition to positivism, a selectionist account for strengthening behavior, the importance of a community of selves, a recursive approach to method, and the probabilistic nature of truth. Questions are raised as to the extent to which Skinner's radical behaviorism, as distinguished from his S-R positivism, may be seen as an extension of Peirce's pragmatism. PMID:22478387

  2. Predicting spatial similarity of freshwater fish biodiversity

    PubMed Central

    Azaele, Sandro; Muneepeerakul, Rachata; Maritan, Amos; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio

    2009-01-01

    A major issue in modern ecology is to understand how ecological complexity at broad scales is regulated by mechanisms operating at the organismic level. What specific underlying processes are essential for a macroecological pattern to emerge? Here, we analyze the analytical predictions of a general model suitable for describing the spatial biodiversity similarity in river ecosystems, and benchmark them against the empirical occurrence data of freshwater fish species collected in the Mississippi–Missouri river system. Encapsulating immigration, emigration, and stochastic noise, and without resorting to species abundance data, the model is able to reproduce the observed probability distribution of the Jaccard similarity index at any given distance. In addition to providing an excellent agreement with the empirical data, this approach accounts for heterogeneities of different subbasins, suggesting a strong dependence of biodiversity similarity on their respective climates. Strikingly, the model can also predict the actual probability distribution of the Jaccard similarity index for any distance when considering just a relatively small sample. The proposed framework supports the notion that simplified macroecological models are capable of predicting fundamental patterns—a theme at the heart of modern community ecology. PMID:19359481

  3. Similarities in Aegyptopithecus and Afropithecus facial morphology.

    PubMed

    Leakey, M G; Leakey, R E; Richtsmeier, J T; Simons, E L; Walker, A C

    1991-01-01

    Recently discovered cranial fossils from the Oligocene deposits of the Fayum depression in Egypt provide many details of the facial morphology of Aegyptopithecus zeuxis. Similar features are found in the Miocene hominoid Afropithecus turkanensis. Their presence is the first good evidence of a strong phenetic link between the Oligocene and Miocene hominoids of Africa. A comparison of trait lists emphasizes the similarities of the two fossil species, and leads us to conclude that the two fossil genera share many primitive facial features. In addition, we studied facial morphology using finite-element scaling analysis and found that the two genera show similarities in morphological integration, or the way in which biological landmarks relate to one another in three dimensions to define the form of the organism. Size differences between the two genera are much greater than the relatively minor shape differences. Analysis of variability in landmark location among the four Aegyptopithecus specimens indicates that variability within the sample is not different from that found within two samples of modern macaques. We propose that the shape differences found among the four Aegyptopithecus specimens simply reflect individual variation in facial characteristics, and that the similarities in facial morphology between Aegyptopithecus and Afropithecus probably represent a complex of primitive facial features retained over millions of years.

  4. Fuzzy similarity measures for ultrasound tissue characterization

    NASA Astrophysics Data System (ADS)

    Emara, Salem M.; Badawi, Ahmed M.; Youssef, Abou-Bakr M.

    1995-03-01

    Computerized ultrasound tissue characterization has become an objective means for diagnosis of diseases. It is difficult to differentiate diffuse liver diseases, namely cirrhotic and fatty liver from a normal one, by visual inspection from the ultrasound images. The visual criteria for differentiating diffused diseases is rather confusing and highly dependent upon the sonographer's experience. The need for computerized tissue characterization is thus justified to quantitatively assist the sonographer for accurate differentiation and to minimize the degree of risk from erroneous interpretation. In this paper we used the fuzzy similarity measure as an approximate reasoning technique to find the maximum degree of matching between an unknown case defined by a feature vector and a family of prototypes (knowledge base). The feature vector used for the matching process contains 8 quantitative parameters (textural, acoustical, and speckle parameters) extracted from the ultrasound image. The steps done to match an unknown case with the family of prototypes (cirr, fatty, normal) are: Choosing the membership functions for each parameter, then obtaining the fuzzification matrix for the unknown case and the family of prototypes, then by the linguistic evaluation of two fuzzy quantities we obtain the similarity matrix, then by a simple aggregation method and the fuzzy integrals we obtain the degree of similarity. Finally, we find that the similarity measure results are comparable to the neural network classification techniques and it can be used in medical diagnosis to determine the pathology of the liver and to monitor the extent of the disease.

  5. Great Apes' Capacities to Recognize Relational Similarity

    ERIC Educational Resources Information Center

    Haun, Daniel B. M.; Call, Josep

    2009-01-01

    Recognizing relational similarity relies on the ability to understand that defining object properties might not lie in the objects individually, but in the relations of the properties of various object to each other. This aptitude is highly relevant for many important human skills such as language, reasoning, categorization and understanding…

  6. Classification of wheat: Badhwar profile similarity technique

    NASA Technical Reports Server (NTRS)

    Austin, W. W.

    1980-01-01

    The Badwar profile similarity classification technique used successfully for classification of corn was applied to spring wheat classifications. The software programs and the procedures used to generate full-scene classifications are presented, and numerical results of the acreage estimations are given.

  7. Similarity of Science Textbooks: A Content Analysis

    ERIC Educational Resources Information Center

    Yost, Michael

    1973-01-01

    Studied the similarity of the astronomy portion in five science textbooks at the fourth through sixth grade levels by comparing students' responses to text authors' requirements. Concluded that the texts had more in common across grade levels than within grade levels. (CC)

  8. Mental Institutions and Similar Phenomena Called Schools

    ERIC Educational Resources Information Center

    Fischer, Ronald W.

    1971-01-01

    Mental institutions and public schools appear to have many similarities, and they often operate in ways that would seem contradictory to their philosophy. This article explores certain atrocities to the self" that result from programs that are intended to be beneficial but, in reality, often result in dehumanization. (Author)

  9. Great Apes' Capacities to Recognize Relational Similarity

    ERIC Educational Resources Information Center

    Haun, Daniel B. M.; Call, Josep

    2009-01-01

    Recognizing relational similarity relies on the ability to understand that defining object properties might not lie in the objects individually, but in the relations of the properties of various object to each other. This aptitude is highly relevant for many important human skills such as language, reasoning, categorization and understanding…

  10. Expertness, Similarity, and Perceived Counselor Competence

    ERIC Educational Resources Information Center

    Spiegel, Sharon Baron

    1976-01-01

    The effects of two levels of counselor similarity and expertness and two types of clients' problems on perceptions of the counselor's competence were tested in this analogue study. Results indicated that suggestions of expertness led to higher evaluations of counselors for both problems. (Author)

  11. [Combination similarity algorithm on chromatographic fingerprints].

    PubMed

    Zhan, Xueyan; Shi, Xinyuan; Duan, Tianxuan; Li, Lei; Qiao, Yanjiang

    2010-11-01

    The similarity of chromatographic fingerprints is one of the effective approaches evaluating the quality stability of Chinese medicine, and the cosine of angle plays an important role in the application of similarity. However, the cosine approach is insensitive to the data difference when the distribution range of the data sets is wide. When the data proportion of the reference sample and the test sample is greatly different, it confirms that the sensitivity of the cosine to the differences of the peaks owned by both the reference sample and the test sample differs from the peaks owned only by the reference sample or the test sample in this study. The method considers the peaks owned by one sample in addition to peaks owned by both samples, and determines their own appropriate weigh targeting for the maximal homostasis value of proportion among the peaks of all of Smilax glabra Roxb. samples. The method based on sample data could reflect the difference in the chemical composition area ratio between the reference sample and test samples sensitively, and measures the similarity among the nine Smilax glabra Roxb. samples, which is a new similarity algorithm for evaluating the quality stability of herbal medicines.

  12. Cognitive Similarity in Normal and Schizogenic Families.

    ERIC Educational Resources Information Center

    Leibowitz, Gerald

    The basic purpose of this study was to measure cognitive similarity, and to test the hypothesis that the cognitive organization of a child (normal or schizophrenic) is more like that of his own parents than it is like that of randomly chosen, unrelated adults. Thirty-six matched family triads, half with sons hospitalized for a schizophrenic…

  13. Looking at faces: first-order and second-order features as determinants of facial appearance.

    PubMed

    Rhodes, Gillian

    2013-01-01

    The encoding and relative importance of first-order (discrete) and second-order (configural) features in mental representations of unfamiliar faces have been investigated. Nonmetric multidimensional scaling (KYST) was carried out on similarity judgments of forty-one photographs of faces (homogeneous with respect to sex, race, facial expression, and, to a lesser extent, age). A large set of ratings, measurements, and ratios of measurements of the faces was regressed against the three-dimensional KYST solution in order to determine the first-order and second-order features used to judge similarity. Parameters characterizing both first-order and second-order features emerged as important determinants of facial similarity. First-order feature parameters characterizing the appearance of the eyes, eyebrows, and mouth, and second-order feature parameters characterizing the position of the eyes, spatial relations between the internal features, and chin shape correlated with the dimensions of the KYST solution. There was little difference in the extent to which first-order and second-order features were encoded. Two higher-level parameters, age and weight, were also used to judge similarity. The implications of these results for mental representations of faces are discussed.

  14. First-Order Approximation of the Ordered Binary-Symmetric Channel

    NASA Technical Reports Server (NTRS)

    Fossorier, Marc P. C.; Lin, Shu

    1996-01-01

    This paper presents different results related to the ordering of a sequence of N received symbols with respect to their reliability measure, for BPSK transmission over the AWGN channel model. First, a tight approximation of Pe (i; N), the probability that the hard decision associated with the i-th symbol of the ordered sequence is in error, is derived. Then, it is shown that despite the fact that the random variables representing the noise at positions n 1(sub 1), n(sub 2), ..., n(sub j) of the ordering are no longer independent, the events of having a hard decision decoding error at these positions remain almost independent Pe (n(sub i), n2, ..., n(sub j); N), the probability that the hard decisions associated with the symbols at positions n(sub 1), n(sub 2), ..., n(sub j), in the ordered sequence are in error, is thus well approximated from each of the Pe (n(sub i): N), for i is a member of [1, j]. Finally, based on the independence of these events, the fully connected 2(sup N) -state BSC representing the channel after ordering is simplified by N independent time-shared 2-state BSC's. This new model allows one to easily and tightly approximate the capacity of the channel after ordering.

  15. Steps to Independent Living Series.

    ERIC Educational Resources Information Center

    Lobb, Nancy

    This set of six activity books and a teacher's guide is designed to help students from eighth grade to adulthood with special needs to learn independent living skills. The activity books have a reading level of 2.5 and address: (1) "How to Get Well When You're Sick or Hurt," including how to take a temperature, see a doctor, and use medicines…

  16. Prospects for an Independent Kurdistan

    DTIC Science & Technology

    2008-03-01

    are mostly Sunni.25 In addition, about 5 percent of the Kurds are Yazidis, which is a “mixture of Islamic, Christian , Jewish, and pagan beliefs...significant political progress has been made by the Kurds of Iraq. The probability of ongoing ethnic and religious strife within Iraq creates an...seek independence. Figure 2 shows the ethno- religious 38 “Guide to Iraqi political parties,” BBC News, http://news.bbc.co.uk

  17. Steps to Independent Living Series.

    ERIC Educational Resources Information Center

    Lobb, Nancy

    This set of six activity books and a teacher's guide is designed to help students from eighth grade to adulthood with special needs to learn independent living skills. The activity books have a reading level of 2.5 and address: (1) "How to Get Well When You're Sick or Hurt," including how to take a temperature, see a doctor, and use medicines…

  18. Scaling exponents for ordered maxima

    SciTech Connect

    Ben-Naim, E.; Krapivsky, P. L.; Lemons, N. W.

    2015-12-22

    We study extreme value statistics of multiple sequences of random variables. For each sequence with N variables, independently drawn from the same distribution, the running maximum is defined as the largest variable to date. We compare the running maxima of m independent sequences and investigate the probability SN that the maxima are perfectly ordered, that is, the running maximum of the first sequence is always larger than that of the second sequence, which is always larger than the running maximum of the third sequence, and so on. The probability SN is universal: it does not depend on the distribution from which the random variables are drawn. For two sequences, SN~N–1/2, and in general, the decay is algebraic, SN~N–σm, for large N. We analytically obtain the exponent σ3≅1.302931 as root of a transcendental equation. Moreover, the exponents σm grow with m, and we show that σm~m for large m.

  19. Scaling exponents for ordered maxima

    DOE PAGES

    Ben-Naim, E.; Krapivsky, P. L.; Lemons, N. W.

    2015-12-22

    We study extreme value statistics of multiple sequences of random variables. For each sequence with N variables, independently drawn from the same distribution, the running maximum is defined as the largest variable to date. We compare the running maxima of m independent sequences and investigate the probability SN that the maxima are perfectly ordered, that is, the running maximum of the first sequence is always larger than that of the second sequence, which is always larger than the running maximum of the third sequence, and so on. The probability SN is universal: it does not depend on the distribution frommore » which the random variables are drawn. For two sequences, SN~N–1/2, and in general, the decay is algebraic, SN~N–σm, for large N. We analytically obtain the exponent σ3≅1.302931 as root of a transcendental equation. Moreover, the exponents σm grow with m, and we show that σm~m for large m.« less

  20. Higher Order Crossings (HOC).

    DTIC Science & Technology

    Results on the higher order crossings approach to signal detection were obtained. In politicular, the earth:s polar notion was analyzed and new...periodicities were obtained. Another application was to online testing for white noise. It was also demonstrated that a higher order crossing sequence will converge to a frequency regardless of the signal to noise ratio. (kr)

  1. Bioregions and World Order.

    ERIC Educational Resources Information Center

    Breakthrough, 1985

    1985-01-01

    What bioregions can do to contribute to world order and security is discussed in this newsletter. A bioregion is defined as an identifiable geographical area of interacting life-systems that is relatively self-sustaining in the ever-renewing processes of nature. Articles included are: "Bioregionalism and World Order" (Gerald Mische);…

  2. Predicting the evolution of complex networks via similarity dynamics

    NASA Astrophysics Data System (ADS)

    Wu, Tao; Chen, Leiting; Zhong, Linfeng; Xian, Xingping

    2017-01-01

    Almost all real-world networks are subject to constant evolution, and plenty of them have been investigated empirically to uncover the underlying evolution mechanism. However, the evolution prediction of dynamic networks still remains a challenging problem. The crux of this matter is to estimate the future network links of dynamic networks. This paper studies the evolution prediction of dynamic networks with link prediction paradigm. To estimate the likelihood of the existence of links more accurate, an effective and robust similarity index is presented by exploiting network structure adaptively. Moreover, most of the existing link prediction methods do not make a clear distinction between future links and missing links. In order to predict the future links, the networks are regarded as dynamic systems in this paper, and a similarity updating method, spatial-temporal position drift model, is developed to simulate the evolutionary dynamics of node similarity. Then the updated similarities are used as input information for the future links' likelihood estimation. Extensive experiments on real-world networks suggest that the proposed similarity index performs better than baseline methods and the position drift model performs well for evolution prediction in real-world evolving networks.

  3. Networks of plants: how to measure similarity in vegetable species.

    PubMed

    Vivaldo, Gianna; Masi, Elisa; Pandolfi, Camilla; Mancuso, Stefano; Caldarelli, Guido

    2016-06-07

    Despite the common misconception of nearly static organisms, plants do interact continuously with the environment and with each other. It is fair to assume that during their evolution they developed particular features to overcome similar problems and to exploit possibilities from environment. In this paper we introduce various quantitative measures based on recent advancements in complex network theory that allow to measure the effective similarities of various species. By using this approach on the similarity in fruit-typology ecological traits we obtain a clear plant classification in a way similar to traditional taxonomic classification. This result is not trivial, since a similar analysis done on the basis of diaspore morphological properties do not provide any clear parameter to classify plants species. Complex network theory can then be used in order to determine which feature amongst many can be used to distinguish scope and possibly evolution of plants. Future uses of this approach range from functional classification to quantitative determination of plant communities in nature.

  4. Anonymous indexing of health conditions for a similarity measure.

    PubMed

    Song, Insu; Marsh, Nigel V

    2012-07-01

    A health social network is an online information service which facilitates information sharing between closely related members of a community with the same or a similar health condition. Over the years, many automated recommender systems have been developed for social networking in order to help users find their communities of interest. For health social networking, the ideal source of information for measuring similarities of patients is the medical information of the patients. However, it is not desirable that such sensitive and private information be shared over the Internet. This is also true for many other security sensitive domains. A new information-sharing scheme is developed where each patient is represented as a small number of (possibly disjoint) d-words (discriminant words) and the d-words are used to measure similarities between patients without revealing sensitive personal information. The d-words are simple words like "food,'' and thus do not contain identifiable personal information. This makes our method an effective one-way hashing of patient assessments for a similarity measure. The d-words can be easily shared on the Internet to find peers who might have similar health conditions.

  5. How similar are recognition memory and inductive reasoning?

    PubMed

    Hayes, Brett K; Heit, Evan

    2013-07-01

    Conventionally, memory and reasoning are seen as different types of cognitive activities driven by different processes. In two experiments, we challenged this view by examining the relationship between recognition memory and inductive reasoning involving multiple forms of similarity. A common study set (members of a conjunctive category) was followed by a test set containing old and new category members, as well as items that matched the study set on only one dimension. The study and test sets were presented under recognition or induction instructions. In Experiments 1 and 2, the inductive property being generalized was varied in order to direct attention to different dimensions of similarity. When there was no time pressure on decisions, patterns of positive responding were strongly affected by property type, indicating that different types of similarity were driving recognition and induction. By comparison, speeded judgments showed weaker property effects and could be explained by generalization based on overall similarity. An exemplar model, GEN-EX (GENeralization from EXamples), could account for both the induction and recognition data. These findings show that induction and recognition share core component processes, even when the tasks involve flexible forms of similarity.

  6. Networks of plants: how to measure similarity in vegetable species

    PubMed Central

    Vivaldo, Gianna; Masi, Elisa; Pandolfi, Camilla; Mancuso, Stefano; Caldarelli, Guido

    2016-01-01

    Despite the common misconception of nearly static organisms, plants do interact continuously with the environment and with each other. It is fair to assume that during their evolution they developed particular features to overcome similar problems and to exploit possibilities from environment. In this paper we introduce various quantitative measures based on recent advancements in complex network theory that allow to measure the effective similarities of various species. By using this approach on the similarity in fruit-typology ecological traits we obtain a clear plant classification in a way similar to traditional taxonomic classification. This result is not trivial, since a similar analysis done on the basis of diaspore morphological properties do not provide any clear parameter to classify plants species. Complex network theory can then be used in order to determine which feature amongst many can be used to distinguish scope and possibly evolution of plants. Future uses of this approach range from functional classification to quantitative determination of plant communities in nature. PMID:27271207

  7. Networks of plants: how to measure similarity in vegetable species

    NASA Astrophysics Data System (ADS)

    Vivaldo, Gianna; Masi, Elisa; Pandolfi, Camilla; Mancuso, Stefano; Caldarelli, Guido

    2016-06-01

    Despite the common misconception of nearly static organisms, plants do interact continuously with the environment and with each other. It is fair to assume that during their evolution they developed particular features to overcome similar problems and to exploit possibilities from environment. In this paper we introduce various quantitative measures based on recent advancements in complex network theory that allow to measure the effective similarities of various species. By using this approach on the similarity in fruit-typology ecological traits we obtain a clear plant classification in a way similar to traditional taxonomic classification. This result is not trivial, since a similar analysis done on the basis of diaspore morphological properties do not provide any clear parameter to classify plants species. Complex network theory can then be used in order to determine which feature amongst many can be used to distinguish scope and possibly evolution of plants. Future uses of this approach range from functional classification to quantitative determination of plant communities in nature.

  8. Quantifying Visual Similarity in Clinical Iconic Graphics

    PubMed Central

    Payne, Philip R.O.; Starren, Justin B.

    2005-01-01

    Objective: The use of icons and other graphical components in user interfaces has become nearly ubiquitous. The interpretation of such icons is based on the assumption that different users perceive the shapes similarly. At the most basic level, different users must agree on which shapes are similar and which are different. If this similarity can be measured, it may be usable as the basis to design better icons. Design: The purpose of this study was to evaluate a novel method for categorizing the visual similarity of graphical primitives, called Presentation Discovery, in the domain of mammography. Six domain experts were given 50 common textual mammography findings and asked to draw how they would represent those findings graphically. Nondomain experts sorted the resulting graphics into groups based on their visual characteristics. The resulting groups were then analyzed using traditional statistics and hypothesis discovery tools. Strength of agreement was evaluated using computational simulations of sorting behavior. Measurements: Sorter agreement was measured at both the individual graphical and concept-group levels using a novel simulation-based method. “Consensus clusters” of graphics were derived using a hierarchical clustering algorithm. Results: The multiple sorters were able to reliably group graphics into similar groups that strongly correlated with underlying domain concepts. Visual inspection of the resulting consensus clusters indicated that graphical primitives that could be informative in the design of icons were present. Conclusion: The method described provides a rigorous alternative to intuitive design processes frequently employed in the design of icons and other graphical interface components. PMID:15684136

  9. Narcissism and birth order.

    PubMed

    Eyring, W E; Sobelman, S

    1996-04-01

    The purpose of this investigation was to clarify the relationship between birth-order position and the development of narcissism, while refining research and theory. The relationship between birth-order status and narcissism was examined with a sample of 79 undergraduate students (55 women and 24 men). These subjects were placed in one of the four following birth-order categories of firstborn, second-born, last-born, and only children. These categories were chosen given their significance in Adlerian theory. Each subject completed the Narcissistic Personality Inventory and a demographic inventory. Based on psychodynamic theory, it was hypothesized that firstborn children were expected to score highest, but statistical significance was not found for an association between narcissism and birth order. Further research is urged to investigate personality theory as it relates to parenting style and birth order.

  10. On the asymptotic similarity of rotating homogeneous turbulence

    NASA Technical Reports Server (NTRS)

    Squires, K. D.; Chasnov, J. R.; Mansour, N. N.

    1994-01-01

    Asymptotic similarity states at large Reynolds numbers and small Rossby numbers in rotating homogeneous turbulence are investigated using the database obtained from large-eddy simulations of the incompressible Navier-Stokes equations. Previous work has shown that the turbulence kinetic energy and integral length scales are accurately described by simple scaling laws based on the low wavenumbers part of the three-dimensional energy spectrum. The primary interest of the present study is to search for spectrum similarity in the asymptotic state. Four independent energy spectra are defined. It is shown that rescaling of these energy spectra in the asymptotic regime will collapse three out of the four spectra. The spectrum which does not collapse is a function only of the vertical wavenumber and corresponds to two-component motions in the plane normal to the rotation axis. Detailed investigation of the cause of this anomalous behavior reveals the existence of a strong reverse cascade of energy from small-to-large scales of the two-dimensional, two-component motions. This feature of the rotating flow is presumably linked to the lack of a complete similarity state, though further study of this issue is required.

  11. 29 CFR 1620.18 - Jobs performed under similar working conditions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 4 2012-07-01 2012-07-01 false Jobs performed under similar working conditions. 1620.18... THE EQUAL PAY ACT § 1620.18 Jobs performed under similar working conditions. (a) In general. In order for the equal pay standard to apply, the jobs are required to be performed under similar working...

  12. 29 CFR 1620.18 - Jobs performed under similar working conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Jobs performed under similar working conditions. 1620.18... THE EQUAL PAY ACT § 1620.18 Jobs performed under similar working conditions. (a) In general. In order for the equal pay standard to apply, the jobs are required to be performed under similar working...

  13. 29 CFR 1620.18 - Jobs performed under similar working conditions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 4 2014-07-01 2014-07-01 false Jobs performed under similar working conditions. 1620.18... THE EQUAL PAY ACT § 1620.18 Jobs performed under similar working conditions. (a) In general. In order for the equal pay standard to apply, the jobs are required to be performed under similar working...

  14. 29 CFR 1620.18 - Jobs performed under similar working conditions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 4 2013-07-01 2013-07-01 false Jobs performed under similar working conditions. 1620.18... THE EQUAL PAY ACT § 1620.18 Jobs performed under similar working conditions. (a) In general. In order for the equal pay standard to apply, the jobs are required to be performed under similar working...

  15. 29 CFR 1620.18 - Jobs performed under similar working conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 4 2011-07-01 2011-07-01 false Jobs performed under similar working conditions. 1620.18... THE EQUAL PAY ACT § 1620.18 Jobs performed under similar working conditions. (a) In general. In order for the equal pay standard to apply, the jobs are required to be performed under similar working...

  16. Spatio-Chromatic Adaptation via Higher-Order Canonical Correlation Analysis of Natural Images

    PubMed Central

    Gutmann, Michael U.; Laparra, Valero; Hyvärinen, Aapo; Malo, Jesús

    2014-01-01

    Independent component and canonical correlation analysis are two general-purpose statistical methods with wide applicability. In neuroscience, independent component analysis of chromatic natural images explains the spatio-chromatic structure of primary cortical receptive fields in terms of properties of the visual environment. Canonical correlation analysis explains similarly chromatic adaptation to different illuminations. But, as we show in this paper, neither of the two methods generalizes well to explain both spatio-chromatic processing and adaptation at the same time. We propose a statistical method which combines the desirable properties of independent component and canonical correlation analysis: It finds independent components in each data set which, across the two data sets, are related to each other via linear or higher-order correlations. The new method is as widely applicable as canonical correlation analysis, and also to more than two data sets. We call it higher-order canonical correlation analysis. When applied to chromatic natural images, we found that it provides a single (unified) statistical framework which accounts for both spatio-chromatic processing and adaptation. Filters with spatio-chromatic tuning properties as in the primary visual cortex emerged and corresponding-colors psychophysics was reproduced reasonably well. We used the new method to make a theory-driven testable prediction on how the neural response to colored patterns should change when the illumination changes. We predict shifts in the responses which are comparable to the shifts reported for chromatic contrast habituation. PMID:24533049

  17. Spatio-chromatic adaptation via higher-order canonical correlation analysis of natural images.

    PubMed

    Gutmann, Michael U; Laparra, Valero; Hyvärinen, Aapo; Malo, Jesús

    2014-01-01

    Independent component and canonical correlation analysis are two general-purpose statistical methods with wide applicability. In neuroscience, independent component analysis of chromatic natural images explains the spatio-chromatic structure of primary cortical receptive fields in terms of properties of the visual environment. Canonical correlation analysis explains similarly chromatic adaptation to different illuminations. But, as we show in this paper, neither of the two methods generalizes well to explain both spatio-chromatic processing and adaptation at the same time. We propose a statistical method which combines the desirable properties of independent component and canonical correlation analysis: It finds independent components in each data set which, across the two data sets, are related to each other via linear or higher-order correlations. The new method is as widely applicable as canonical correlation analysis, and also to more than two data sets. We call it higher-order canonical correlation analysis. When applied to chromatic natural images, we found that it provides a single (unified) statistical framework which accounts for both spatio-chromatic processing and adaptation. Filters with spatio-chromatic tuning properties as in the primary visual cortex emerged and corresponding-colors psychophysics was reproduced reasonably well. We used the new method to make a theory-driven testable prediction on how the neural response to colored patterns should change when the illumination changes. We predict shifts in the responses which are comparable to the shifts reported for chromatic contrast habituation.

  18. 49 CFR 1013.1 - The independence of the trustee of a voting trust.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 8 2011-10-01 2011-10-01 false The independence of the trustee of a voting trust... VOTING TRUSTS § 1013.1 The independence of the trustee of a voting trust. (a) In order to avoid an... complete independence from the creator of the trust (the settlor). (c) Neither the trustee, the...

  19. 49 CFR 1013.1 - The independence of the trustee of a voting trust.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false The independence of the trustee of a voting trust... VOTING TRUSTS § 1013.1 The independence of the trustee of a voting trust. (a) In order to avoid an... complete independence from the creator of the trust (the settlor). (c) Neither the trustee, the...

  20. 49 CFR 1013.1 - The independence of the trustee of a voting trust.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 8 2014-10-01 2014-10-01 false The independence of the trustee of a voting trust... VOTING TRUSTS § 1013.1 The independence of the trustee of a voting trust. (a) In order to avoid an... complete independence from the creator of the trust (the settlor). (c) Neither the trustee, the...