The Importance of Isomorphism for Conclusions about Homology: A Bayesian Multilevel Structural Equation Modeling Approach with Ordinal Indicators

PubMed Central

Guenole, Nigel

2016-01-01

We describe a Monte Carlo study examining the impact of assuming item isomorphism (i.e., equivalent construct meaning across levels of analysis) on conclusions about homology (i.e., equivalent structural relations across levels of analysis) under varying degrees of non-isomorphism in the context of ordinal indicator multilevel structural equation models (MSEMs). We focus on the condition where one or more loadings are higher on the between level than on the within level to show that while much past research on homology has ignored the issue of psychometric isomorphism, psychometric isomorphism is in fact critical to valid conclusions about homology. More specifically, when a measurement model with non-isomorphic items occupies an exogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the within level exogenous latent variance is under-estimated leading to over-estimation of the within level structural coefficient, while the between level exogenous latent variance is overestimated leading to underestimation of the between structural coefficient. When a measurement model with non-isomorphic items occupies an endogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the endogenous within level latent variance is under-estimated leading to under-estimation of the within level structural coefficient while the endogenous between level latent variance is over-estimated leading to over-estimation of the between level structural coefficient. The innovative aspect of this article is demonstrating that even minor violations of psychometric isomorphism render claims of homology untenable. We also show that posterior predictive p-values for ordinal indicator Bayesian MSEMs are insensitive to violations of isomorphism even when they lead to severely biased within and between level structural parameters. We highlight conditions where poor estimation of even correctly specified models rules out empirical examination of isomorphism and homology without taking precautions, for instance, larger Level-2 sample sizes, or using informative priors. PMID:26973580

Topological T-duality, automorphisms and classifying spaces

NASA Astrophysics Data System (ADS)

Pande, Ashwin S.

2014-08-01

We extend the formalism of Topological T-duality to spaces which are the total space of a principal S1-bundle p:E→W with an H-flux in H3(E,Z) together with an automorphism of the continuous-trace algebra on E determined by H. The automorphism is a ‘topological approximation’ to a gerby gauge transformation of spacetime. We motivate this physically from Buscher’s Rules for T-duality. Using the Equivariant Brauer Group, we connect this problem to the C∗-algebraic formalism of Topological T-duality of Mathai and Rosenberg (2005). We show that the study of this problem leads to the study of a purely topological problem, namely, Topological T-duality of triples (p,b,H) consisting of isomorphism classes of a principal circle bundle p:X→B and classes b∈H2(X,Z) and H∈H3(X,Z). We construct a classifying space R for triples in a manner similar to the work of Bunke and Schick (2005). We characterize R up to homotopy and study some of its properties. We show that it possesses a natural self-map which induces T-duality for triples. We study some properties of this map.

A lattice model for data display

NASA Technical Reports Server (NTRS)

Hibbard, William L.; Dyer, Charles R.; Paul, Brian E.

1994-01-01

In order to develop a foundation for visualization, we develop lattice models for data objects and displays that focus on the fact that data objects are approximations to mathematical objects and real displays are approximations to ideal displays. These lattice models give us a way to quantize the information content of data and displays and to define conditions on the visualization mappings from data to displays. Mappings satisfy these conditions if and only if they are lattice isomorphisms. We show how to apply this result to scientific data and display models, and discuss how it might be applied to recursively defined data types appropriate for complex information processing.

Isomorphic pressures, institutional strategies, and knowledge creation in the health care sector.

PubMed

Yang, Chen-Wei; Fang, Shih-Chieh; Huang, Wei-Min

2007-01-01

Health care organizations are facing surprisingly complex challenges, including new treatment and diagnostic technologies, ongoing pressures for health care institutional reform, the emergence of new organizational governance structures, and knowledge creation for the health care system. To maintain legitimacy in demanding environments, organizations tend to copy practices of similar organizations, which lead to isomorphism, and to use internal strategies to accommodate changes. A concern is that a poor fit between isomorphic pressures and internal strategies can interfere with developmental processes, such as knowledge creation. The purposes of this article are to, first, develop a set of propositions, based on institutional theory, as a theoretical framework that might explain the influence of isomorphic pressures on institutional processes through which knowledge is created within the health care sector and, second, propose that a good fit between isomorphic pressures factors and health care organizations' institutional strategic choices will enhance the health care organizations' ability to create knowledge. To develop a theoretical framework, we developed a set of propositions based on literature pertaining to the institutional theory perspective of isomorphic pressures and the response of health care organizations to isomorphic pressures. Institutional theory perspectives of isomorphic pressures and institutional strategies may provide a new understanding for health care organizations seeking effective knowledge creation strategies within institutional environment of health care sector. First, the ability to identify three forces for isomorphic change is critical for managers. Second, the importance of a contingency approach by health care managers can lead to strategies tailoring to cope with uncertainties facing their organizations.

Using an isomorphic problem pair to learn introductory physics: Transferring from a two-step problem to a three-step problem

NASA Astrophysics Data System (ADS)

Lin, Shih-Yin; Singh, Chandralekha

2013-12-01

In this study, we examine introductory physics students’ ability to perform analogical reasoning between two isomorphic problems which employ the same underlying physics principles but have different surface features. 382 students from a calculus-based and an algebra-based introductory physics course were administered a quiz in the recitation in which they had to learn from a solved problem provided and take advantage of what they learned from it to solve another isomorphic problem (which we call the quiz problem). The solved problem provided has two subproblems while the quiz problem has three subproblems, which is known from previous research to be challenging for introductory students. In addition to the solved problem, students also received extra scaffolding supports that were intended to help them discern and exploit the underlying similarities of the isomorphic solved and quiz problems. The data analysis suggests that students had great difficulty in transferring what they learned from a two-step problem to a three-step problem. Although most students were able to learn from the solved problem to some extent with the scaffolding provided and invoke the relevant principles in the quiz problem, they were not necessarily able to apply the principles correctly. We also conducted think-aloud interviews with six introductory students in order to understand in depth the difficulties they had and explore strategies to provide better scaffolding. The interviews suggest that students often superficially mapped the principles employed in the solved problem to the quiz problem without necessarily understanding the governing conditions underlying each principle and examining the applicability of the principle in the new situation in an in-depth manner. Findings suggest that more scaffolding is needed to help students in transferring from a two-step problem to a three-step problem and applying the physics principles appropriately. We outline a few possible strategies for future investigation.

The metaphor-gestalt synergy underlying the self-organisation of perception as a semiotic process.

PubMed

Rail, David

2013-04-01

Recently the basis of concept and language formation has been redefined by the proposal that they both stem from perception and embodiment. The experiential revolution has lead to a far more integrated and dynamic understanding of perception as a semiotic system. The emergence of meaning in the perceptual process stems from the interaction between two key mechanisms. These are first, the generation of schemata through recurrent sensorimotor activity (SM) that underlies category and language formation (L). The second is the interaction between metaphor (M) and gestalt mechanisms (G) that generate invariant mappings beyond the SM domain that both conserve and diversify our understanding and meaning potential. We propose an important advance in our understanding of perception as a semiotic system through exploring the affect of self-organising to criticality where hierarchical behaviour becomes widely integrated through 1/f process and isomorphisms. Our proposal leads to several important implications. First, that SM and L form a functional isomorphism depicted as SM <=> L. We contend that SM <=> L is emergent, corresponding to the phenomenal self. Second, meaning structures the isomorphism SM <=>L through the synergy between M and G (M-G). M-G synergy is based on a combination of structuring and imagination. We contend that the interaction between M-G and SM <=> L functions as a macro-micro comutation that governs perception as semiosis. We discuss how our model relates to current research in fractal time and verb formation.

Path-integral isomorphic Hamiltonian for including nuclear quantum effects in non-adiabatic dynamics

NASA Astrophysics Data System (ADS)

Tao, Xuecheng; Shushkov, Philip; Miller, Thomas F.

2018-03-01

We describe a path-integral approach for including nuclear quantum effects in non-adiabatic chemical dynamics simulations. For a general physical system with multiple electronic energy levels, a corresponding isomorphic Hamiltonian is introduced such that Boltzmann sampling of the isomorphic Hamiltonian with classical nuclear degrees of freedom yields the exact quantum Boltzmann distribution for the original physical system. In the limit of a single electronic energy level, the isomorphic Hamiltonian reduces to the familiar cases of either ring polymer molecular dynamics (RPMD) or centroid molecular dynamics Hamiltonians, depending on the implementation. An advantage of the isomorphic Hamiltonian is that it can easily be combined with existing mixed quantum-classical dynamics methods, such as surface hopping or Ehrenfest dynamics, to enable the simulation of electronically non-adiabatic processes with nuclear quantum effects. We present numerical applications of the isomorphic Hamiltonian to model two- and three-level systems, with encouraging results that include improvement upon a previously reported combination of RPMD with surface hopping in the deep-tunneling regime.

T-duality simplifies bulk-boundary correspondence: the noncommutative case

NASA Astrophysics Data System (ADS)

Hannabuss, Keith C.; Mathai, Varghese; Thiang, Guo Chuan

2018-05-01

We state and prove a general result establishing that T-duality, or the Connes-Thom isomorphism, simplifies the bulk-boundary correspondence, given by a boundary map in K-theory, in the sense of converting it to a simple geometric restriction map. This settles in the affirmative several earlier conjectures of the authors and provides a clear geometric picture of the correspondence. In particular, our result holds in arbitrary spatial dimension, in both the real and complex cases, and also in the presence of disorder, magnetic fields, and H-flux. These special cases are relevant both to string theory and to the study of the quantum Hall effect and topological insulators with defects in condensed matter physics.

a Triangular Deformation of the Two-Dimensional POINCARÉ Algebra

NASA Astrophysics Data System (ADS)

Khorrami, M.; Shariati, A.; Abolhassani, M. R.; Aghamohammadi, A.

Contracting the h-deformation of SL(2, ℝ), we construct a new deformation of two-dimensional Poincaré's algebra, the algebra of functions on its group and its differential structure. It is seen that these dual Hopf algebras are isomorphic to each other. It is also shown that the Hopf algebra is triangular, and its universal R-matrix is also constructed explicitly. We then find a deformation map for the universal enveloping algebra, and at the end, give the deformed mass shells and Lorentz transformation.

Heuristics of Twelfth Graders Building Isomorphisms

ERIC Educational Resources Information Center

Powell, Arthur B.; Maher, Carolyn A.

2003-01-01

This report analyzes the discursive interactions of four students to understand what heuristic methods they develop as well as how and why they build isomorphisms to resolve a combinatorial problem set in a non-Euclidian context. The findings suggest that results of their heuristic actions lead them to build isomorphisms that in turn allow them to…

Institutional Isomorphism and the Creation of the Unified National System of Higher Education in Australia: An Empirical Analysis

ERIC Educational Resources Information Center

Croucher, Gwilym; Woelert, Peter

2016-01-01

Previous research has highlighted the occurrence of isomorphic tendencies--convergences in terms of formal organizational structure--in higher education systems in times of uncertainty and under external pressure to change. It has been repeatedly claimed that the Australian university system largely followed a logic of isomorphic change in the…

The construction of combinatorial manifolds with prescribed sets of links of vertices

NASA Astrophysics Data System (ADS)

Gaifullin, A. A.

2008-10-01

To every oriented closed combinatorial manifold we assign the set (with repetitions) of isomorphism classes of links of its vertices. The resulting transformation \\mathcal{L} is the main object of study in this paper. We pose an inversion problem for \\mathcal{L} and show that this problem is closely related to Steenrod's problem on the realization of cycles and to the Rokhlin-Schwartz-Thom construction of combinatorial Pontryagin classes. We obtain a necessary condition for a set of isomorphism classes of combinatorial spheres to belong to the image of \\mathcal{L}. (Sets satisfying this condition are said to be balanced.) We give an explicit construction showing that every balanced set of isomorphism classes of combinatorial spheres falls into the image of \\mathcal{L} after passing to a multiple set and adding several pairs of the form (Z,-Z), where -Z is the sphere Z with the orientation reversed. Given any singular simplicial cycle \\xi of a space X, this construction enables us to find explicitly a combinatorial manifold M and a map \\varphi\\colon M\\to X such that \\varphi_* \\lbrack M \\rbrack =r[\\xi] for some positive integer r. The construction is based on resolving singularities of \\xi. We give applications of the main construction to cobordisms of manifolds with singularities and cobordisms of simple cells. In particular, we prove that every rational additive invariant of cobordisms of manifolds with singularities admits a local formula. Another application is the construction of explicit (though inefficient) local combinatorial formulae for polynomials in the rational Pontryagin classes of combinatorial manifolds.

Rotational response of superconductors: Magnetorotational isomorphism and rotation-induced vortex lattice

NASA Astrophysics Data System (ADS)

Babaev, Egor; Svistunov, Boris

2014-03-01

The analysis of nonclassical rotational response of superfluids and superconductors was performed by Onsager [Onsager, Nuovo Cimento, Suppl. 6, 279 (1949), 10.1007/BF02780991] and London [Superfluids (Wiley, New York, 1950)] and crucially advanced by Feynman [Prog. Low Temp. Phys. 1, 17 (1955), 10.1016/S0079-6417(08)60077-3]. It was established that, in the thermodynamic limit, neutral superfluids rotate by forming—without any threshold—a vortex lattice. In contrast, the rotation of superconductors at angular frequency Ω—supported by uniform magnetic field BL∝Ω due to surface currents—is of the rigid-body type (London law). Here we show that, neglecting the centrifugal effects, the behavior of a rotating superconductor is identical to that of a superconductor placed in a uniform fictitious external magnetic field H ˜=-BL. In particular, the isomorphism immediately implies the existence of two critical rotational frequencies in type-2 superconductors.

Assessing Student Expertise in Introductory Physics with Isomorphic Problems. II. Effect of Some Potential Factors on Problem Solving and Transfer

ERIC Educational Resources Information Center

Chandralekha; Singh

2008-01-01

In this paper, we explore the use of isomorphic problem pairs (IPPs) to assess introductory physics students' ability to solve and successfully transfer problem-solving knowledge from one context to another in mechanics. We call the paired problems "isomorphic" because they require the same physics principle to solve them. We analyze written…

A Method to Determine of All Non-Isomorphic Groups of Order 16

ERIC Educational Resources Information Center

Valcan, Dumitru

2012-01-01

Many students or teachers ask themselves: Being given a natural number n, how many non-isomorphic groups of order n exists? The answer, generally, is not yet given. But, for certain values of the number n have answered this question. The present work gives a method to determine of all non-isomorphic groups of order 16 and gives descriptions of all…

Veridical mapping in savant abilities, absolute pitch, and synesthesia: an autism case study

PubMed Central

Bouvet, Lucie; Donnadieu, Sophie; Valdois, Sylviane; Caron, Chantal; Dawson, Michelle; Mottron, Laurent

2014-01-01

An enhanced role and autonomy of perception are prominent in autism. Furthermore, savant abilities, absolute pitch, and synesthesia are all more commonly found in autistic individuals than in the typical population. The mechanism of veridical mapping has been proposed to account for how enhanced perception in autism leads to the high prevalence of these three phenomena and their structural similarity. Veridical mapping entails functional rededication of perceptual brain regions to higher order cognitive operations, allowing the enhanced detection and memorization of isomorphisms between perceptual and non-perceptual structures across multiple scales. In this paper, we present FC, an autistic individual who possesses several savant abilities in addition to both absolute pitch and synesthesia-like associations. The co-occurrence in FC of abilities, some of them rare, which share the same structure, as well as FC’s own accounts of their development, together suggest the importance of veridical mapping in the atypical range and nature of abilities displayed by autistic people. PMID:24600416

Simplicity of condensed matter at its core: generic definition of a Roskilde-simple system.

PubMed

Schrøder, Thomas B; Dyre, Jeppe C

2014-11-28

The isomorph theory is reformulated by defining Roskilde-simple systems by the property that the order of the potential energies of configurations at one density is maintained when these are scaled uniformly to a different density. If the potential energy as a function of all particle coordinates is denoted by U(R), this requirement translates into U(Ra) < U(Rb) ⇒ U(λRa) < U(λRb). Isomorphs remain curves in the thermodynamic phase diagram along which structure, dynamics, and excess entropy are invariant, implying that the phase diagram is effectively one-dimensional with respect to many reduced-unit properties. In contrast to the original formulation of the isomorph theory, however, the density-scaling exponent is not exclusively a function of density and the isochoric heat capacity is not an exact isomorph invariant. A prediction is given for the latter quantity's variation along the isomorphs. Molecular dynamics simulations of the Lennard-Jones and Lennard-Jones Gaussian systems validate the new approach.

Isomorphic red blood cells using automated urine flow cytometry is a reliable method in diagnosis of bladder cancer.

PubMed

Muto, Satoru; Sugiura, Syo-Ichiro; Nakajima, Akiko; Horiuchi, Akira; Inoue, Masahiro; Saito, Keisuke; Isotani, Shuji; Yamaguchi, Raizo; Ide, Hisamitsu; Horie, Shigeo

2014-10-01

We aimed to identify patients with a chief complaint of hematuria who could safely avoid unnecessary radiation and instrumentation in the diagnosis of bladder cancer (BC), using automated urine flow cytometry to detect isomorphic red blood cells (RBCs) in urine. We acquired urine samples from 134 patients over the age of 35 years with a chief complaint of hematuria and a positive urine occult blood test or microhematuria. The data were analyzed using the UF-1000i (®) (Sysmex Co., Ltd., Kobe, Japan) automated urine flow cytometer to determine RBC morphology, which was classified as isomorphic or dysmorphic. The patients were divided into two groups (BC versus non-BC) for statistical analysis. Multivariate logistic regression analysis was used to determine the predictive value of flow cytometry versus urine cytology, the bladder tumor antigen test, occult blood in urine test, and microhematuria test. BC was confirmed in 26 of 134 patients (19.4 %). The area under the curve for RBC count using the automated urine flow cytometer was 0.94, representing the highest reference value obtained in this study. Isomorphic RBCs were detected in all patients in the BC group. On multivariate logistic regression analysis, only isomorphic RBC morphology was significantly predictive for BC (p < 0.001). Analytical parameters such as sensitivity, specificity, positive predictive value, and negative predictive value of isomorphic RBCs in urine were 100.0, 91.7, 74.3, and 100.0 %, respectively. Detection of urinary isomorphic RBCs using automated urine flow cytometry is a reliable method in the diagnosis of BC with hematuria.

Membrane protein structure determination by SAD, SIR, or SIRAS phasing in serial femtosecond crystallography using an iododetergent

PubMed Central

Nakane, Takanori; Hanashima, Shinya; Suzuki, Mamoru; Saiki, Haruka; Hayashi, Taichi; Kakinouchi, Keisuke; Sugiyama, Shigeru; Kawatake, Satoshi; Matsuoka, Shigeru; Matsumori, Nobuaki; Nango, Eriko; Kobayashi, Jun; Shimamura, Tatsuro; Kimura, Kanako; Mori, Chihiro; Kunishima, Naoki; Sugahara, Michihiro; Takakyu, Yoko; Inoue, Shigeyuki; Masuda, Tetsuya; Hosaka, Toshiaki; Tono, Kensuke; Joti, Yasumasa; Kameshima, Takashi; Hatsui, Takaki; Inoue, Tsuyoshi; Nureki, Osamu; Iwata, So; Murata, Michio; Mizohata, Eiichi

2016-01-01

The 3D structure determination of biological macromolecules by X-ray crystallography suffers from a phase problem: to perform Fourier transformation to calculate real space density maps, both intensities and phases of structure factors are necessary; however, measured diffraction patterns give only intensities. Although serial femtosecond crystallography (SFX) using X-ray free electron lasers (XFELs) has been steadily developed since 2009, experimental phasing still remains challenging. Here, using 7.0-keV (1.771 Å) X-ray pulses from the SPring-8 Angstrom Compact Free Electron Laser (SACLA), iodine single-wavelength anomalous diffraction (SAD), single isomorphous replacement (SIR), and single isomorphous replacement with anomalous scattering (SIRAS) phasing were performed in an SFX regime for a model membrane protein bacteriorhodopsin (bR). The crystals grown in bicelles were derivatized with an iodine-labeled detergent heavy-atom additive 13a (HAD13a), which contains the magic triangle, I3C head group with three iodine atoms. The alkyl tail was essential for binding of the detergent to the surface of bR. Strong anomalous and isomorphous difference signals from HAD13a enabled successful phasing using reflections up to 2.1-Å resolution from only 3,000 and 4,000 indexed images from native and derivative crystals, respectively. When more images were merged, structure solution was possible with data truncated at 3.3-Å resolution, which is the lowest resolution among the reported cases of SFX phasing. Moreover, preliminary SFX experiment showed that HAD13a successfully derivatized the G protein-coupled A2a adenosine receptor crystallized in lipidic cubic phases. These results pave the way for de novo structure determination of membrane proteins, which often diffract poorly, even with the brightest XFEL beams. PMID:27799539

Membrane protein structure determination by SAD, SIR, or SIRAS phasing in serial femtosecond crystallography using an iododetergent.

PubMed

Nakane, Takanori; Hanashima, Shinya; Suzuki, Mamoru; Saiki, Haruka; Hayashi, Taichi; Kakinouchi, Keisuke; Sugiyama, Shigeru; Kawatake, Satoshi; Matsuoka, Shigeru; Matsumori, Nobuaki; Nango, Eriko; Kobayashi, Jun; Shimamura, Tatsuro; Kimura, Kanako; Mori, Chihiro; Kunishima, Naoki; Sugahara, Michihiro; Takakyu, Yoko; Inoue, Shigeyuki; Masuda, Tetsuya; Hosaka, Toshiaki; Tono, Kensuke; Joti, Yasumasa; Kameshima, Takashi; Hatsui, Takaki; Yabashi, Makina; Inoue, Tsuyoshi; Nureki, Osamu; Iwata, So; Murata, Michio; Mizohata, Eiichi

2016-11-15

The 3D structure determination of biological macromolecules by X-ray crystallography suffers from a phase problem: to perform Fourier transformation to calculate real space density maps, both intensities and phases of structure factors are necessary; however, measured diffraction patterns give only intensities. Although serial femtosecond crystallography (SFX) using X-ray free electron lasers (XFELs) has been steadily developed since 2009, experimental phasing still remains challenging. Here, using 7.0-keV (1.771 Å) X-ray pulses from the SPring-8 Angstrom Compact Free Electron Laser (SACLA), iodine single-wavelength anomalous diffraction (SAD), single isomorphous replacement (SIR), and single isomorphous replacement with anomalous scattering (SIRAS) phasing were performed in an SFX regime for a model membrane protein bacteriorhodopsin (bR). The crystals grown in bicelles were derivatized with an iodine-labeled detergent heavy-atom additive 13a (HAD13a), which contains the magic triangle, I3C head group with three iodine atoms. The alkyl tail was essential for binding of the detergent to the surface of bR. Strong anomalous and isomorphous difference signals from HAD13a enabled successful phasing using reflections up to 2.1-Å resolution from only 3,000 and 4,000 indexed images from native and derivative crystals, respectively. When more images were merged, structure solution was possible with data truncated at 3.3-Å resolution, which is the lowest resolution among the reported cases of SFX phasing. Moreover, preliminary SFX experiment showed that HAD13a successfully derivatized the G protein-coupled A2a adenosine receptor crystallized in lipidic cubic phases. These results pave the way for de novo structure determination of membrane proteins, which often diffract poorly, even with the brightest XFEL beams.

Steenrod homotopy

NASA Astrophysics Data System (ADS)

Melikhov, Sergey A.

2009-06-01

Steenrod homotopy theory is a natural framework for doing algebraic topology on general spaces in terms of algebraic topology of polyhedra; or from a different viewpoint, it studies the topology of the \\lim^1 functor (for inverse sequences of groups). This paper is primarily concerned with the case of compacta, in which Steenrod homotopy coincides with strong shape. An attempt is made to simplify the foundations of the theory and to clarify and improve some of its major results. With geometric tools such as Milnor's telescope compactification, comanifolds (=mock bundles), and the Pontryagin-Thom construction, new simple proofs are obtained for results by Barratt-Milnor, Geoghegan-Krasinkiewicz, Dydak, Dydak-Segal, Krasinkiewicz-Minc, Cathey, Mittag-Leffler-Bourbaki, Fox, Eda-Kawamura, Edwards-Geoghegan, Jussila, and for three unpublished results by Shchepin. An error in Lisitsa's proof of the `Hurewicz theorem in Steenrod homotopy' is corrected. It is shown that over compacta, R.H. Fox's overlayings are equivalent to I.M. James' uniform covering maps. Other results include: \\bullet A morphism between inverse sequences of countable (possibly non-Abelian) groups that induces isomorphisms on \\lim and \\lim^1 is invertible in the pro-category. This implies the `Whitehead theorem in Steenrod homotopy', thereby answering two questions of Koyama. \\bullet If X is an LC_{n-1}-compactum, n\\ge 1, then its n-dimensional Steenrod homotopy classes are representable by maps S^n\\to\

Automorphisms of Order Structures of Abelian Parts of Operator Algebras and Their Role in Quantum Theory

NASA Astrophysics Data System (ADS)

Hamhalter, Jan; Turilova, Ekaterina

2014-10-01

It is shown that any order isomorphism between the structures of unital associative JB subalgebras of JB algebras is given naturally by a partially linear Jordan isomorphism. The same holds for nonunital subalgebras and order isomorphisms preserving the unital subalgebra. Finally, we recover usual action of time evolution group on a von Neumann factor from group of automorphisms of the structure of Abelian subalgebras.

Experimental Demonstration of Isomorphism.

ERIC Educational Resources Information Center

Kamenicek, J.; Melicharek, M.

2000-01-01

Describes some simple experiments related to the properties of crystals. Illustrates isomorphism using single crystals of alum. Presents experiments for determining how various mixture compositions affect the growth of salt crystals. (WRM)

An novel frequent probability pattern mining algorithm based on circuit simulation method in uncertain biological networks.

PubMed

He, Jieyue; Wang, Chunyan; Qiu, Kunpu; Zhong, Wei

2014-01-01

Motif mining has always been a hot research topic in bioinformatics. Most of current research on biological networks focuses on exact motif mining. However, due to the inevitable experimental error and noisy data, biological network data represented as the probability model could better reflect the authenticity and biological significance, therefore, it is more biological meaningful to discover probability motif in uncertain biological networks. One of the key steps in probability motif mining is frequent pattern discovery which is usually based on the possible world model having a relatively high computational complexity. In this paper, we present a novel method for detecting frequent probability patterns based on circuit simulation in the uncertain biological networks. First, the partition based efficient search is applied to the non-tree like subgraph mining where the probability of occurrence in random networks is small. Then, an algorithm of probability isomorphic based on circuit simulation is proposed. The probability isomorphic combines the analysis of circuit topology structure with related physical properties of voltage in order to evaluate the probability isomorphism between probability subgraphs. The circuit simulation based probability isomorphic can avoid using traditional possible world model. Finally, based on the algorithm of probability subgraph isomorphism, two-step hierarchical clustering method is used to cluster subgraphs, and discover frequent probability patterns from the clusters. The experiment results on data sets of the Protein-Protein Interaction (PPI) networks and the transcriptional regulatory networks of E. coli and S. cerevisiae show that the proposed method can efficiently discover the frequent probability subgraphs. The discovered subgraphs in our study contain all probability motifs reported in the experiments published in other related papers. The algorithm of probability graph isomorphism evaluation based on circuit simulation method excludes most of subgraphs which are not probability isomorphism and reduces the search space of the probability isomorphism subgraphs using the mismatch values in the node voltage set. It is an innovative way to find the frequent probability patterns, which can be efficiently applied to probability motif discovery problems in the further studies.

An novel frequent probability pattern mining algorithm based on circuit simulation method in uncertain biological networks

PubMed Central

2014-01-01

Background Motif mining has always been a hot research topic in bioinformatics. Most of current research on biological networks focuses on exact motif mining. However, due to the inevitable experimental error and noisy data, biological network data represented as the probability model could better reflect the authenticity and biological significance, therefore, it is more biological meaningful to discover probability motif in uncertain biological networks. One of the key steps in probability motif mining is frequent pattern discovery which is usually based on the possible world model having a relatively high computational complexity. Methods In this paper, we present a novel method for detecting frequent probability patterns based on circuit simulation in the uncertain biological networks. First, the partition based efficient search is applied to the non-tree like subgraph mining where the probability of occurrence in random networks is small. Then, an algorithm of probability isomorphic based on circuit simulation is proposed. The probability isomorphic combines the analysis of circuit topology structure with related physical properties of voltage in order to evaluate the probability isomorphism between probability subgraphs. The circuit simulation based probability isomorphic can avoid using traditional possible world model. Finally, based on the algorithm of probability subgraph isomorphism, two-step hierarchical clustering method is used to cluster subgraphs, and discover frequent probability patterns from the clusters. Results The experiment results on data sets of the Protein-Protein Interaction (PPI) networks and the transcriptional regulatory networks of E. coli and S. cerevisiae show that the proposed method can efficiently discover the frequent probability subgraphs. The discovered subgraphs in our study contain all probability motifs reported in the experiments published in other related papers. Conclusions The algorithm of probability graph isomorphism evaluation based on circuit simulation method excludes most of subgraphs which are not probability isomorphism and reduces the search space of the probability isomorphism subgraphs using the mismatch values in the node voltage set. It is an innovative way to find the frequent probability patterns, which can be efficiently applied to probability motif discovery problems in the further studies. PMID:25350277

Liquid state isomorphism, Rosenfeld-Tarazona temperature scaling, and Riemannian thermodynamic geometry.

PubMed

Mausbach, Peter; Köster, Andreas; Vrabec, Jadran

2018-05-01

Aspects of isomorph theory, Rosenfeld-Tarazona temperature scaling, and thermodynamic geometry are comparatively discussed on the basis of the Lennard-Jones potential. The first two approaches approximate the high-density fluid state well when the repulsive interparticle interactions become dominant, which is typically the case close to the freezing line. However, previous studies of Rosenfeld-Tarazona scaling for the isochoric heat capacity and its relation to isomorph theory reveal deviations for the temperature dependence. It turns out that a definition of a state region in which repulsive interactions dominate is required for achieving consistent results. The Riemannian thermodynamic scalar curvature R allows for such a classification, indicating predominantly repulsive interactions by R>0. An analysis of the isomorphic character of the freezing line and the validity of Rosenfeld-Tarazona temperature scaling show that these approaches are consistent only in a small state region.

X-ray diffraction measurement of cosolvent accessible volume in rhombohedral insulin crystals

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

Soares, Alexei S.; Caspar, Donald L. D.

We report x-ray crystallographic measurement of the number of solvent electrons in the unit cell of a protein crystal equilibrated with aqueous solutions of different densities provides information about preferential hydration in the crystalline state. Room temperature and cryo-cooled rhombohedral insulin crystals were equilibrated with 1.2 M trehalose to study the effect of lowered water activity. The native and trehalose soaked crystals were isomorphous and had similar structures. Including all the low resolution data, the amplitudes of the structure factors were put on an absolute scale (in units of electrons per asymmetric unit) by constraining the integrated number of electronsmore » inside the envelope of the calculated protein density map to equal the number deduced from the atomic model. This procedure defines the value of F(0 0 0), the amplitude at the origin of the Fourier transform, which is equal to the total number of electrons in the asymmetric unit (i.e. protein plus solvent). Comparison of the F(0 0 0) values for three isomorphous pairs of room temperature insulin crystals, three with trehalose and three without trehalose, indicates that 75 ± 12 electrons per asymmetric unit were added to the crystal solvent when soaked in 1.2 M trehalose. If all the water in the crystal were available as solvent for the trehalose, 304 electrons would have been added. Thus, the co-solvent accessible volume is one quarter of the total water in the crystal. Finally, determination of the total number of electrons in a protein crystal is an essential first step for mapping the average density distribution of the disordered solvent.« less

X-ray diffraction measurement of cosolvent accessible volume in rhombohedral insulin crystals

DOE PAGES

Soares, Alexei S.; Caspar, Donald L. D.

2017-08-31

We report x-ray crystallographic measurement of the number of solvent electrons in the unit cell of a protein crystal equilibrated with aqueous solutions of different densities provides information about preferential hydration in the crystalline state. Room temperature and cryo-cooled rhombohedral insulin crystals were equilibrated with 1.2 M trehalose to study the effect of lowered water activity. The native and trehalose soaked crystals were isomorphous and had similar structures. Including all the low resolution data, the amplitudes of the structure factors were put on an absolute scale (in units of electrons per asymmetric unit) by constraining the integrated number of electronsmore » inside the envelope of the calculated protein density map to equal the number deduced from the atomic model. This procedure defines the value of F(0 0 0), the amplitude at the origin of the Fourier transform, which is equal to the total number of electrons in the asymmetric unit (i.e. protein plus solvent). Comparison of the F(0 0 0) values for three isomorphous pairs of room temperature insulin crystals, three with trehalose and three without trehalose, indicates that 75 ± 12 electrons per asymmetric unit were added to the crystal solvent when soaked in 1.2 M trehalose. If all the water in the crystal were available as solvent for the trehalose, 304 electrons would have been added. Thus, the co-solvent accessible volume is one quarter of the total water in the crystal. Finally, determination of the total number of electrons in a protein crystal is an essential first step for mapping the average density distribution of the disordered solvent.« less

Geometric properties of commutative subalgebras of partial differential operators

NASA Astrophysics Data System (ADS)

Zheglov, A. B.; Kurke, H.

2015-05-01

We investigate further algebro-geometric properties of commutative rings of partial differential operators, continuing our research started in previous articles. In particular, we start to explore the simplest and also certain known examples of quantum algebraically completely integrable systems from the point of view of a recent generalization of Sato's theory, developed by the first author. We give a complete characterization of the spectral data for a class of 'trivial' commutative algebras and strengthen geometric properties known earlier for a class of known examples. We also define a kind of restriction map from the moduli space of coherent sheaves with fixed Hilbert polynomial on a surface to an analogous moduli space on a divisor (both the surface and the divisor are part of the spectral data). We give several explicit examples of spectral data and corresponding algebras of commuting (completed) operators, producing as a by-product interesting examples of surfaces that are not isomorphic to spectral surfaces of any (maximal) commutative ring of partial differential operators of rank one. Finally, we prove that any commutative ring of partial differential operators whose normalization is isomorphic to the ring of polynomials k \\lbrack u,t \\rbrack is a Darboux transformation of a ring of operators with constant coefficients. Bibliography: 39 titles.

Parameter space exploration within dynamic simulations of signaling networks.

PubMed

De Ambrosi, Cristina; Barla, Annalisa; Tortolina, Lorenzo; Castagnino, Nicoletta; Pesenti, Raffaele; Verri, Alessandro; Ballestrero, Alberto; Patrone, Franco; Parodi, Silvio

2013-02-01

We started offering an introduction to very basic aspects of molecular biology, for the reader coming from computer sciences, information technology, mathematics. Similarly we offered a minimum of information about pathways and networks in graph theory, for a reader coming from the bio-medical sector. At the crossover about the two different types of expertise, we offered some definition about Systems Biology. The core of the article deals with a Molecular Interaction Map (MIM), a network of biochemical interactions involved in a small signaling-network sub-region relevant in breast cancer. We explored robustness/sensitivity to random perturbations. It turns out that our MIM is a non-isomorphic directed graph. For non physiological directions of propagation of the signal the network is quite resistant to perturbations. The opposite happens for biologically significant directions of signal propagation. In these cases we can have no signal attenuation, and even signal amplification. Signal propagation along a given pathway is highly unidirectional, with the exception of signal-feedbacks, that again have a specific biological role and significance. In conclusion, even a relatively small network like our present MIM reveals the preponderance of specific biological functions over unspecific isomorphic behaviors. This is perhaps the consequence of hundreds of millions of years of biological evolution.

The evolutionary and genetic origins of consciousness in the Cambrian Period over 500 million years ago

PubMed Central

Feinberg, Todd E.; Mallatt, Jon

2013-01-01

Vertebrates evolved in the Cambrian Period before 520 million years ago, but we do not know when or how consciousness arose in the history of the vertebrate brain. Here we propose multiple levels of isomorphic or somatotopic neural representations as an objective marker for sensory consciousness. All extant vertebrates have these, so we deduce that consciousness extends back to the group's origin. The first conscious sense may have been vision. Then vision, coupled with additional sensory systems derived from ectodermal placodes and neural crest, transformed primitive reflexive systems into image forming brains that map and perceive the external world and the body's interior. We posit that the minimum requirement for sensory consciousness and qualia is a brain including a forebrain (but not necessarily a developed cerebral cortex/pallium), midbrain, and hindbrain. This brain must also have (1) hierarchical systems of intercommunicating, isomorphically organized, processing nuclei that extensively integrate the different senses into representations that emerge in upper levels of the neural hierarchy; and (2) a widespread reticular formation that integrates the sensory inputs and contributes to attention, awareness, and neural synchronization. We propose a two-step evolutionary history, in which the optic tectum was the original center of multi-sensory conscious perception (as in fish and amphibians: step 1), followed by a gradual shift of this center to the dorsal pallium or its cerebral cortex (in mammals, reptiles, birds: step 2). We address objections to the hypothesis and call for more studies of fish and amphibians. In our view, the lamprey has all the neural requisites and is likely the simplest extant vertebrate with sensory consciousness and qualia. Genes that pattern the proposed elements of consciousness (isomorphism, neural crest, placodes) have been identified in all vertebrates. Thus, consciousness is in the genes, some of which are already known. PMID:24109460

Crystallization, dehydration and experimental phasing of WbdD, a bifunctional kinase and methyltransferase from Escherichia coli O9a

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

Hagelueken, Gregor; Huang, Hexian; Harlos, Karl

2012-10-01

The optimization of WbdD crystals using a novel dehydration protocol and experimental phasing at 3.5 Å resolution by cross-crystal averaging followed by molecular replacement of electron density into a non-isomorphous 3.0 Å resolution native data set are reported. WbdD is a bifunctional kinase/methyltransferase that is responsible for regulation of lipopolysaccharide O antigen polysaccharide chain length in Escherichia coli serotype O9a. Solving the crystal structure of this protein proved to be a challenge because the available crystals belonging to space group I23 only diffracted to low resolution (>95% of the crystals diffracted to resolution lower than 4 Å and most onlymore » to 8 Å) and were non-isomorphous, with changes in unit-cell dimensions of greater than 10%. Data from a serendipitously found single native crystal that diffracted to 3.0 Å resolution were non-isomorphous with a lower (3.5 Å) resolution selenomethionine data set. Here, a strategy for improving poor (3.5 Å resolution) initial phases by density modification and cross-crystal averaging with an additional 4.2 Å resolution data set to build a crude model of WbdD is desribed. Using this crude model as a mask to cut out the 3.5 Å resolution electron density yielded a successful molecular-replacement solution of the 3.0 Å resolution data set. The resulting map was used to build a complete model of WbdD. The hydration status of individual crystals appears to underpin the variable diffraction quality of WbdD crystals. After the initial structure had been solved, methods to control the hydration status of WbdD were developed and it was thus possible to routinely obtain high-resolution diffraction (to better than 2.5 Å resolution). This novel and facile crystal-dehydration protocol may be useful for similar challenging situations.« less

The evolutionary and genetic origins of consciousness in the Cambrian Period over 500 million years ago.

PubMed

Feinberg, Todd E; Mallatt, Jon

2013-01-01

Vertebrates evolved in the Cambrian Period before 520 million years ago, but we do not know when or how consciousness arose in the history of the vertebrate brain. Here we propose multiple levels of isomorphic or somatotopic neural representations as an objective marker for sensory consciousness. All extant vertebrates have these, so we deduce that consciousness extends back to the group's origin. The first conscious sense may have been vision. Then vision, coupled with additional sensory systems derived from ectodermal placodes and neural crest, transformed primitive reflexive systems into image forming brains that map and perceive the external world and the body's interior. We posit that the minimum requirement for sensory consciousness and qualia is a brain including a forebrain (but not necessarily a developed cerebral cortex/pallium), midbrain, and hindbrain. This brain must also have (1) hierarchical systems of intercommunicating, isomorphically organized, processing nuclei that extensively integrate the different senses into representations that emerge in upper levels of the neural hierarchy; and (2) a widespread reticular formation that integrates the sensory inputs and contributes to attention, awareness, and neural synchronization. We propose a two-step evolutionary history, in which the optic tectum was the original center of multi-sensory conscious perception (as in fish and amphibians: step 1), followed by a gradual shift of this center to the dorsal pallium or its cerebral cortex (in mammals, reptiles, birds: step 2). We address objections to the hypothesis and call for more studies of fish and amphibians. In our view, the lamprey has all the neural requisites and is likely the simplest extant vertebrate with sensory consciousness and qualia. Genes that pattern the proposed elements of consciousness (isomorphism, neural crest, placodes) have been identified in all vertebrates. Thus, consciousness is in the genes, some of which are already known.

Interacting damage models mapped onto ising and percolation models

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

Toussaint, Renaud; Pride, Steven R.

The authors introduce a class of damage models on regular lattices with isotropic interactions between the broken cells of the lattice. Quasistatic fiber bundles are an example. The interactions are assumed to be weak, in the sense that the stress perturbation from a broken cell is much smaller than the mean stress in the system. The system starts intact with a surface-energy threshold required to break any cell sampled from an uncorrelated quenched-disorder distribution. The evolution of this heterogeneous system is ruled by Griffith's principle which states that a cell breaks when the release in potential (elastic) energy in themore » system exceeds the surface-energy barrier necessary to break the cell. By direct integration over all possible realizations of the quenched disorder, they obtain the probability distribution of each damage configuration at any level of the imposed external deformation. They demonstrate an isomorphism between the distributions so obtained and standard generalized Ising models, in which the coupling constants and effective temperature in the Ising model are functions of the nature of the quenched-disorder distribution and the extent of accumulated damage. In particular, they show that damage models with global load sharing are isomorphic to standard percolation theory, that damage models with local load sharing rule are isomorphic to the standard ising model, and draw consequences thereof for the universality class and behavior of the autocorrelation length of the breakdown transitions corresponding to these models. they also treat damage models having more general power-law interactions, and classify the breakdown process as a function of the power-law interaction exponent. Last, they also show that the probability distribution over configurations is a maximum of Shannon's entropy under some specific constraints related to the energetic balance of the fracture process, which firmly relates this type of quenched-disorder based damage model to standard statistical mechanics.« less

Algebraic K-theory, K-regularity, and -duality of -stable C ∗-algebras

NASA Astrophysics Data System (ADS)

Mahanta, Snigdhayan

2015-12-01

We develop an algebraic formalism for topological -duality. More precisely, we show that topological -duality actually induces an isomorphism between noncommutative motives that in turn implements the well-known isomorphism between twisted K-theories (up to a shift). In order to establish this result we model topological K-theory by algebraic K-theory. We also construct an E ∞ -operad starting from any strongly self-absorbing C ∗-algebra . Then we show that there is a functorial topological K-theory symmetric spectrum construction on the category of separable C ∗-algebras, such that is an algebra over this operad; moreover, is a module over this algebra. Along the way we obtain a new symmetric spectra valued functorial model for the (connective) topological K-theory of C ∗-algebras. We also show that -stable C ∗-algebras are K-regular providing evidence for a conjecture of Rosenberg. We conclude with an explicit description of the algebraic K-theory of a x+ b-semigroup C ∗-algebras coming from number theory and that of -stabilized noncommutative tori.

Multielemental analyses of isomorphous Indian garnet gemstones by XRD and external pixe techniques.

PubMed

Venkateswarulu, P; Srinivasa Rao, K; Kasipathi, C; Ramakrishna, Y

2012-12-01

Garnet gemstones were collected from parts of Eastern Ghats geological formations of Andhra Pradesh, India and their gemological studies were carried out. Their study of chemistry is not possible as they represent mixtures of isomorphism nature, and none of the individual specimens indicate independent chemistry. Hence, non-destructive instrumental methodology of external PIXE technique was employed to understand their chemistry and identity. A 3 MeV proton beam was employed to excite the samples. In the present study geochemical characteristics of garnet gemstones were studied by proton induced X-ray emission. Almandine variety of garnet is found to be abundant in the present study by means of their chemical contents. The crystal structure and the lattice parameters were estimated using X-Ray Diffraction studies. The trace and minor elements are estimated using PIXE technique and major compositional elements are confirmed by XRD studies. The technique is found very useful in characterizing the garnet gemstones. The present work, thus establishes usefulness and versatility of the PIXE technique with external beam for research in Geo-scientific methodology. Copyright © 2012 Elsevier Ltd. All rights reserved.

Barrels, stripes, and fingerprints in the brain - implications for theories of cortical organization.

PubMed

Catania, Kenneth C

2002-01-01

In the last decade improvements in the histological processing of cortical tissue in conjunction with the investigation of additional mammalian species in comparative brain studies has expanded the information available to guide theories of cortical organization. Here I review some of these recent findings in the somatosensory system with an emphasis on modules related to specializations of the peripheral sensory surface. The diversity of modular representations, or cortical "isomorphs" suggest that information from the sensory sheet guides many of the features of cortical maps and suggest that cortex is not constrained to form circular units in the form of a traditional cortical column.

A mechanism of institutional isomorphism in referral networks among hospitals in Seoul, South Korea.

PubMed

Jung, Minsoo; Choi, Mankyu

2010-01-01

Hospitals engage in medical referral system relations voluntarily, by virtue of their own service capacities. These capacities include medical technology, equipment supply, and patient management, which are assessed individually by medical institutions in efforts to control costs and maintain efficiency in tertiary hospitals. This study assessed referral networks according to the institutional isomorphism theory of new economic sociology. As a result, the referral networks were shown to exhibit emergent structural hierarchy via cumulative clustering by established year and were not affected by attributive variables such as region, bed number, and year of establishment. In particular, the networks evidenced institutional isomorphism with certain central hospitals. As a consequence, personal indices were shown to decrease in accordance with its period, and only the structural index increased. Normative pressures cause organizations to become hierarchically homogenized, in accordance with the principle of organizational learning in specialized fields. Therefore, normative isomorphism on the basis of public domains should be considered an inherent factor in the development of referral networks.

Quantum-chemical modeling of smectite clays

NASA Technical Reports Server (NTRS)

Aronowitz, S.; Coyne, L.; Lawless, J.; Rishpon, J.

1982-01-01

A self-consistent charge extended Hueckel program is used in modeling isomorphic substitution of Al(3+) by Na(+), K(+), Mg(2+), Fe(2+), and Fe(3+) in the octahedral layer of a dioctahedral smectite clay, such as montmorillonite. Upon comparison of the energies involved in the isomorphic substitution, it is found that the order for successful substitution is as follows: Al(3+), Fe(3+), Mg(2+), Fe(2+), Na(+), which is equivalent to Ca(2+), and then K(+). This ordering is found to be consistent with experimental observation. The calculations also make it possible to determine the possible penetration of metal ions into the clay's 2:1 crystalline layer. For the cases studied, this type of penetration can occur at elevated temperatures into regions where isomorphic substitution has occurred with metal ions that bear a formal charge of less than 3+. The computed behavior of the electronic structure in the presence of isomorphic substitution is found to be similar to behavior associated with semiconductors.

Students Building Isomorphisms

ERIC Educational Resources Information Center

Uptegrove, Elizabeth B.; Maher, Carolyn A.

2004-01-01

This paper reports on five students' explorations of structural relationships between problem situations that they worked on over several years as participants in a long-term study. In particular, we describe the case of students who recognized isomorphisms between and among two problem situations and who used particular features of the problems…

'You'll See That Everywhere': Institutional Isomorphism in Secondary School Subject Departments

ERIC Educational Resources Information Center

Puttick, Steven

2017-01-01

This paper asks why spatially separated school departments might exhibit, in different ways, very similar practices. Data from an ethnographic study of three secondary school geography departments in England are discussed through a concept of "isomorphism" (homogenising forces), drawn from neo-institutional theory. Similarities across…

A general number-to-space mapping deficit in developmental dyscalculia.

PubMed

Huber, S; Sury, D; Moeller, K; Rubinsten, O; Nuerk, H-C

2015-01-01

Previous research on developmental dyscalculia (DD) suggested that deficits in the number line estimation task are related to a failure to represent number magnitude linearly. This conclusion was derived from the observation of logarithmically shaped estimation patterns. However, recent research questioned this idea of an isomorphic relationship between estimation patterns and number magnitude representation. In the present study, we evaluated an alternative hypothesis: impairments in the number line estimation task are due to a general deficit in mapping numbers onto space. Adults with DD and a matched control group had to learn linear and non-linear layouts of the number line via feedback. Afterwards, we assessed their performance how well they learnt the new number-space mappings. We found irrespective of the layouts worse performance of adults with DD. Additionally, in case of the linear layout, we observed that their performance did not differ from controls near reference points, but that differences between groups increased as the distance to reference point increased. We conclude that worse performance of adults with DD in the number line task might be due a deficit in mapping numbers onto space which can be partly overcome relying on reference points. Copyright © 2015 Elsevier Ltd. All rights reserved.

Adinkras from ordered quartets of BC4 Coxeter group elements and regarding 1,358,954,496 matrix elements of the Gadget

NASA Astrophysics Data System (ADS)

Gates, S. James; Guyton, Forrest; Harmalkar, Siddhartha; Kessler, David S.; Korotkikh, Vadim; Meszaros, Victor A.

2017-06-01

We examine values of the Adinkra Holoraumy-induced Gadget representation space metric over all possible four-color, four-open node, and four-closed node adinkras. Of the 1,358,954,496 gadget matrix elements, only 226,492,416 are non-vanishing and take on one of three values: -1/3, 1/3, or 1 and thus a subspace isomorphic to a description of a body-centered tetrahedral molecule emerges.

Super-elite plasma rings and the orbits of planets and satellites isomorphic to the orbits of electrons in the Bohr's model of the hydrogen atom

NASA Astrophysics Data System (ADS)

Rabinovich, B. I.

2007-10-01

This paper continues the series of papers [1 5] and generalizes the previous results to a proto-ring of magnetized plasma whose density decreases in the radial direction. The problem of quantization of the sector and orbital velocities, and of the radii and periods of revolution of elite plasma rings is considered. A new concept of super-elite rings is introduced. Their isomorphism with the orbits of the planets and planetary satellites in the Solar System is proved. This isomorphism also extends to the orbits of electrons in the Bohr’s model of the hydrogen atom.

A square-plate piezoelectric linear motor operating in two orthogonal and isomorphic face-diagonal-bending modes.

PubMed

Ci, Penghong; Chen, Zhijiang; Liu, Guoxi; Dong, Shuxiang

2014-01-01

We report a piezoelectric linear motor made of a single Pb(Zr,Ti)O3 square-plate, which operates in two orthogonal and isomorphic face-diagonal-bending modes to produce precision linear motion. A 15 × 15 × 2 mm prototype was fabricated, and the motor generated a driving force of up to 1.8 N and a speed of 170 mm/s under an applied voltage of 100 Vpp at the resonance frequency of 136.5 kHz. The motor shows such advantages as large driving force under relatively low driving voltage, simple structure, and stable motion because of its isomorphic face-diagonal-bending mode.

An Isomorphism between Lyapunov Exponents and Shannon's Channel Capacity

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

Friedland, Gerald; Metere, Alfredo

We demonstrate that discrete Lyapunov exponents are isomorphic to numeric overflows of the capacity of an arbitrary noiseless and memoryless channel in a Shannon communication model with feedback. The isomorphism allows the understanding of Lyapunov exponents in terms of Information Theory, rather than the traditional definitions in chaos theory. The result also implies alternative approaches to the calculation of related quantities, such as the Kolmogorov Sinai entropy which has been linked to thermodynamic entropy. This work provides a bridge between fundamental physics and information theory. It suggests, among other things, that machine learning and other information theory methods can bemore » employed at the core of physics simulations.« less

Effectiveness of metaphoric facilitation techniques in a challenge course program on the empowerment of women participants

Treesearch

Penny A. James; Lynn Anderson; Anderson Young

2007-01-01

Research has shown support for the efficacy of differing processing techniques, particularly isomorphic framing. Feminist practitioners contend this methodology disempowers participants. Proponents argue this could result only from improper implementation. This experiment employed a facilitation technique (control, derived, isomorphic) between subjects design with time...

Testing after Worked Example Study Does Not Enhance Delayed Problem-Solving Performance Compared to Restudy

ERIC Educational Resources Information Center

van Gog, Tamara; Kester, Liesbeth; Dirkx, Kim; Hoogerheide, Vincent; Boerboom, Joris; Verkoeijen, Peter P. J. L.

2015-01-01

Four experiments investigated whether the testing effect also applies to the acquisition of problem-solving skills from worked examples. Experiment 1 (n?=?120) showed no beneficial effects of testing consisting of "isomorphic" problem solving or "example recall" on final test performance, which consisted of isomorphic problem…

Parallel Process and Isomorphism: A Model for Decision Making in the Supervisory Triad

ERIC Educational Resources Information Center

Koltz, Rebecca L.; Odegard, Melissa A.; Feit, Stephen S.; Provost, Kent; Smith, Travis

2012-01-01

Parallel process and isomorphism are two supervisory concepts that are often discussed independently but rarely discussed in connection with each other. These two concepts, philosophically, have different historical roots, as well as different implications for interventions with regard to the supervisory triad. The authors examine the difference…

Reinventing the Concepts of Group and Isomorphism: The Case of Jessica and Sandra

ERIC Educational Resources Information Center

Larsen, Sean

2009-01-01

The purpose of this paper is to describe the process by which a pair of undergraduate students, participating in a teaching experiment, reinvented (with guidance) the concepts of group and isomorphism beginning with an exploration of the symmetries of an equilateral triangle. The intent of this description is to highlight some important insights…

A Case of Mimetic Isomorphism: A Short-Cut to Increasing Loyalty to Academia

ERIC Educational Resources Information Center

Orkodashvili, Mariam

2008-01-01

The paper discusses the process of shortening career path to leadership positions in academia that could serve as an example of mimetic isomorphism, where university tries to apply business-like quick result-oriented strategies. This strategy incentivizes young faculty to stay in universities and keep loyalty to academia. This process could also…

Children's Construction of Mathematical Knowledge in Solving Novel Isomorphic Problems in Concrete and Written Form.

ERIC Educational Resources Information Center

English, Lyn D.

1996-01-01

Presents case study data of low- and high-achieving nine-year olds focusing on construction and analogical transfer of mathematical knowledge during novel problem solving, as reflected in strategies for dealing with isomorphic combinatorial problems presented in hands-on and written form. Results showed that achievement level does not predict…

Are Phonological Representations of Printed and Spoken Language Isomorphic? Evidence from the Restrictions on Unattested Onsets

ERIC Educational Resources Information Center

Berent, Iris

2008-01-01

Are the phonological representations of printed and spoken words isomorphic? This question is addressed by investigating the restrictions on onsets. Cross-linguistic research suggests that onsets of rising sonority are preferred to sonority plateaus, which, in turn, are preferred to sonority falls (e.g., bnif, bdif, lbif). Of interest is whether…

Optimal seasonal schedules and the relative dominance of heteromorphic and isomorphic life cycles in macroalgae.

PubMed

Bessho, Kazuhiro; Iwasa, Yoh

2010-11-21

Marine macroalgae (seaweed) show diverse life cycles. Species with a heteromorphic life cycle have a large multicellular algal body in one generation but have a very small body in the second generation of the same year. In contrast, the diploid and haploid life forms of isomorphic species have similar morphology, and these species often have more than two generations in a year. Here, we first study the optimal life cycle schedule of marine macroalgae when daily mortality changes seasonally, and then we discuss the conditions for coexistence and relative dominance of different life cycles. According to the optimal life cycle schedule, heteromorphic species tend to have a generation with a large algal body when mortality is low, and a microscopic-sized generation when mortality is high. In contrast, isomorphic species tend to mature when body size reaches a threshold value that is the same for different generations. We then examine the coexistence of the two life cycles when growth rate decreases with biomass. The model predicts that (1) at high latitudes (i.e., in strongly seasonal environments), heteromorphic species are likely to dominate over isomorphic species, and (2) species with a heteromorphic life cycle should dominate in the supratidal and upper intertidal zones where macroalgae tend to suffer high mortality, and also in the subtidal zone, where mortality is low, whereas isomorphic species are likely to be more successful when mortality is intermediate. These predictions are consistent with the observed distribution patterns of the two life cycles in macroalgae. Copyright © 2010 Elsevier Ltd. All rights reserved.

Delay discounting of food by rhesus monkeys: Cocaine and food choice in isomorphic and allomorphic situations.

PubMed

Huskinson, Sally L; Woolverton, William L; Green, Leonard; Myerson, Joel; Freeman, Kevin B

2015-06-01

Research on delay discounting has focused largely on nondrug reinforcers in an isomorphic context in which choice is between alternatives that involve the same type of reinforcer. Less often, delay discounting has been studied with drug reinforcers in a more ecologically valid allomorphic context where choice is between alternatives involving different types of reinforcers. The present experiment is the first to examine discounting of drug and nondrug reinforcers in both isomorphic and allomorphic situations using a theoretical model (i.e., the hyperbolic discounting function) that allows for comparisons of discounting rates between reinforcer types and amounts. The goal of the current experiment was to examine discounting of a delayed, nondrug reinforcer (food) by male rhesus monkeys when the immediate alternative was either food (isomorphic situation) or cocaine (allomorphic situation). In addition, we sought to determine whether there was a magnitude effect with delayed food in the allomorphic situation. Choice of immediate food and immediate cocaine increased with amount and dose, respectively. Choice functions for immediate food and cocaine generally shifted leftward as delay increased. Compared to isomorphic situations in which food was the immediate alternative, delayed food was discounted more steeply in allomorphic situations where cocaine was the immediate alternative. Notably, discounting was not affected by the magnitude of the delayed reinforcer. These data indicate that how steeply a delayed nondrug reinforcer is discounted may depend more on the qualitative characteristics of the immediate reinforcer and less on the magnitude of the delayed one. (c) 2015 APA, all rights reserved).

Force, Velocity, and Work: The Effects of Different Contexts on Students' Understanding of Vector Concepts Using Isomorphic Problems

ERIC Educational Resources Information Center

Barniol, Pablo; Zavala, Genaro

2014-01-01

In this article we compare students' understanding of vector concepts in problems with no physical context, and with three mechanics contexts: force, velocity, and work. Based on our "Test of Understanding of Vectors," a multiple-choice test presented elsewhere, we designed two isomorphic shorter versions of 12 items each: a test with no…

Effect of Inoculant Alloy Selection and Particle Size on Efficiency of Isomorphic Inoculation of Ti-Al

PubMed Central

Rouat, Bernard; Daloz, Dominique; Bouzy, Emmanuel

2018-01-01

The process of isomorphic inoculation relies on precise selection of inoculant alloys for a given system. Three alloys, Ti-10Al-25Nb, Ti-25Al-10Ta, and Ti-47Ta (at %) were selected as potential isomorphic inoculants for a Ti-46Al alloy. The binary Ti-Ta alloy selected was found to be ineffective as an inoculant due to its large density difference with the melt, causing the particles to settle. Both ternary alloys were successfully implemented as isomorphic inoculants that decreased the equiaxed grain size and increased the equiaxed fraction in their ingots. The degree of grain refinement obtained was found to be dependent on the number of particles introduced to the melt. Also, more new grains were formed than particles added to the melt. The grains/particle efficiency varied from greater than one to nearly twenty as the size of the particle increased. This is attributed to the breaking up of particles into smaller particles by dissolution in the melt. For a given particle size, Ti-Al-Ta and Ti-Al-Nb particles were found to have a roughly similar grain/particle efficiency. PMID:29693591

Scattering theory for graphs isomorphic to a regular tree at infinity

NASA Astrophysics Data System (ADS)

Colin de Verdière, Yves; Truc, Françoise

2013-06-01

We describe the spectral theory of the adjacency operator of a graph which is isomorphic to a regular tree at infinity. Using some combinatorics, we reduce the problem to a scattering problem for a finite rank perturbation of the adjacency operator on a regular tree. We develop this scattering theory using the classical recipes for Schrödinger operators in Euclidian spaces.

Simple nuclear C*-algebras not isomorphic to their opposites

PubMed Central

Hirshberg, Ilan

2017-01-01

We show that it is consistent with Zermelo–Fraenkel set theory with the axiom of choice (ZFC) that there is a simple nuclear nonseparable C∗-algebra, which is not isomorphic to its opposite algebra. We can furthermore guarantee that this example is an inductive limit of unital copies of the Cuntz algebra O2 or of the canonical anticommutation relations (CAR) algebra. PMID:28559339

Complex-valued time-series correlation increases sensitivity in FMRI analysis.

PubMed

Kociuba, Mary C; Rowe, Daniel B

2016-07-01

To develop a linear matrix representation of correlation between complex-valued (CV) time-series in the temporal Fourier frequency domain, and demonstrate its increased sensitivity over correlation between magnitude-only (MO) time-series in functional MRI (fMRI) analysis. The standard in fMRI is to discard the phase before the statistical analysis of the data, despite evidence of task related change in the phase time-series. With a real-valued isomorphism representation of Fourier reconstruction, correlation is computed in the temporal frequency domain with CV time-series data, rather than with the standard of MO data. A MATLAB simulation compares the Fisher-z transform of MO and CV correlations for varying degrees of task related magnitude and phase amplitude change in the time-series. The increased sensitivity of the complex-valued Fourier representation of correlation is also demonstrated with experimental human data. Since the correlation description in the temporal frequency domain is represented as a summation of second order temporal frequencies, the correlation is easily divided into experimentally relevant frequency bands for each voxel's temporal frequency spectrum. The MO and CV correlations for the experimental human data are analyzed for four voxels of interest (VOIs) to show the framework with high and low contrast-to-noise ratios in the motor cortex and the supplementary motor cortex. The simulation demonstrates the increased strength of CV correlations over MO correlations for low magnitude contrast-to-noise time-series. In the experimental human data, the MO correlation maps are noisier than the CV maps, and it is more difficult to distinguish the motor cortex in the MO correlation maps after spatial processing. Including both magnitude and phase in the spatial correlation computations more accurately defines the correlated left and right motor cortices. Sensitivity in correlation analysis is important to preserve the signal of interest in fMRI data sets with high noise variance, and avoid excessive processing induced correlation. Copyright © 2016 Elsevier Inc. All rights reserved.

The Dixmier Map for Nilpotent Super Lie Algebras

NASA Astrophysics Data System (ADS)

Herscovich, Estanislao

2012-07-01

In this article we prove that there exists a Dixmier map for nilpotent super Lie algebras. In other words, if we denote by {Prim({U}({g}))} the set of (graded) primitive ideals of the enveloping algebra {{U}({g})} of a nilpotent Lie superalgebra {{g}} and {{A}d0} the adjoint group of {{g}0}, we prove that the usual Dixmier map for nilpotent Lie algebras can be naturally extended to the context of nilpotent super Lie algebras, i.e. there exists a bijective map I : {g}0^{*}/{A}d0 rightarrow Prim({U}({g})) defined by sending the equivalence class [ λ] of a functional λ to a primitive ideal I( λ) of {{U}({g})}, and which coincides with the Dixmier map in the case of nilpotent Lie algebras. Moreover, the construction of the previous map is explicit, and more or less parallel to the one for Lie algebras, a major difference with a previous approach ( cf. [18]). One key fact in the construction is the existence of polarizations for super Lie algebras, generalizing the concept defined for Lie algebras. As a corollary of the previous description, we obtain the isomorphism {{U}({g})/I(λ) ˜eq Cliffq(k) ⊗ Ap(k)}, where {(p,q) = (dim({g}0/{g}0^{λ})/2,dim({g}1/{g}1^{λ}))}, we get a direct construction of the maximal ideals of the underlying algebra of {{U}({g})} and also some properties of the stabilizers of the primitive ideals of {{U}({g})}.

Crystallization and preliminary X-ray crystallographic analysis of the cysteine protease inhibitor clitocypin

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

Galeša, Katja; Brzin, Jože; Sabotič, Jerica

2006-01-01

Clitocypin is a cysteine protease inhibitor from the mushroom Clitocybe nebularis. The protein has been purified from natural sources and crystallized in a variety of non-isomorphous forms belonging to monoclinic and triclinic space groups. Clitocypin is a cysteine protease inhibitor from the mushroom Clitocybe nebularis. The protein has been purified from natural sources and crystallized in a variety of non-isomorphous forms belonging to monoclinic and triclinic space groups. A diffraction data set to 1.55 Å resolution was obtained from a crystal belonging to space group P2, with unit-cell parameters a = 38.326, b = 33.597, c = 55.568 Å, βmore » = 104°. An inability to achieve isomorphism forced the use of MAD and SAD phasing methods. Phasing is in progress.« less

T-Duality in an H-Flux: Exchange of Momentum and Winding

NASA Astrophysics Data System (ADS)

Han, Fei; Mathai, Varghese

2018-02-01

Using our earlier proposal for Ramond-Ramond fields in an H-flux on loop space (Han et al. in Commun Math Phys 337(1):127-150, 2015. arXiv:1405.1320), we extend the Hori isomorphism in Bouwknegt et al. (Commun Math Phys 249:383-415, 2004. arXiv:hep-th/0306062; Phys Rev Lett 92:181601, 2004. arXiv:hep-th/0312052) from invariant differential forms, to invariant exotic differential forms such that the momentum and winding numbers are exchanged, filling in a gap in the literature. We also extend the compatibility of the action of invariant exact Courant algebroids on the T-duality isomorphism in Cavalcanti and Gualtieri (in: CRM proceedings of lecture notes, vol 50, pp 341-365, American Mathematical Society, Providence, 2010 ), to the T-duality isomorphism on exotic invariant differential forms.

The Motivic Cofiber of tau and Exotic Periodicities

NASA Astrophysics Data System (ADS)

Gheorghe, Bogdan

Consider the Tate twist tau epsilon H0,1 (S0,0) in the mod 2 cohomology of the motivic sphere. After 2-completion, the motivic Adams spectral sequence realizes this element as a map tau : S0,-1 → S0,0 . This thesis begins with the study of its cofiber, that we denote by Ctau. We first show that this motivic 2-cell complex can be endowed with a unique Einfinity ring structure. This promotes the known isomorphism pi *,* Ctau ≅ Ext *,* BP*BP (BP*, BP* ) to an isomorphism of rings which also preserves higher products. This structure allows us to consider its closed symmetric monoidal category of modules (Ctau Mod, - ∧Ctau -), which happens to live in the kernel of Betti realization. This category has surprising applications, and moreover contains many interesting motivic spectra. In particular, we construct exotic motivic fields K( wn), detecting motivic wn-periodicity. This theory of motivic wn-periodicity can be roughly seen as perpendicular to the vn-periodicity story, detected by the motivic Morava K-theories K( n). Finally, we also explain why the category Ctau Mod is so computable. The above isomor phism comes in a more structured version. In work that is joint with Zhouli Xu and Guozhen Wang, we show that there is an equivalence of infinity-categories Db ( MGL *,* MGL Comodev) ≅ → Ctau Cellcomp between an algebraic derived category, and the subcategory Ctau Cellcomp of cellular Ctau- modules that are complete with respect to a version of the algebraic cobordism spectrum MGL.

Zeroth Poisson Homology, Foliated Cohomology and Perfect Poisson Manifolds

NASA Astrophysics Data System (ADS)

Martínez-Torres, David; Miranda, Eva

2018-01-01

We prove that, for compact regular Poisson manifolds, the zeroth homology group is isomorphic to the top foliated cohomology group, and we give some applications. In particular, we show that, for regular unimodular Poisson manifolds, top Poisson and foliated cohomology groups are isomorphic. Inspired by the symplectic setting, we define what a perfect Poisson manifold is. We use these Poisson homology computations to provide families of perfect Poisson manifolds.

Using isomorphic problems to learn introductory physics

NASA Astrophysics Data System (ADS)

Lin, Shih-Yin; Singh, Chandralekha

2011-12-01

In this study, we examine introductory physics students’ ability to perform analogical reasoning between two isomorphic problems which employ the same underlying physics principles but have different surface features. Three hundred sixty-two students from a calculus-based and an algebra-based introductory physics course were given a quiz in the recitation in which they had to first learn from a solved problem provided and take advantage of what they learned from it to solve another problem (which we call the quiz problem) which was isomorphic. Previous research suggests that the multiple-concept quiz problem is challenging for introductory students. Students in different recitation classes received different interventions in order to help them discern and exploit the underlying similarities of the isomorphic solved and quiz problems. We also conducted think-aloud interviews with four introductory students in order to understand in depth the difficulties they had and explore strategies to provide better scaffolding. We found that most students were able to learn from the solved problem to some extent with the scaffolding provided and invoke the relevant principles in the quiz problem. However, they were not necessarily able to apply the principles correctly. Research suggests that more scaffolding is needed to help students in applying these principles appropriately. We outline a few possible strategies for future investigation.

SING: Subgraph search In Non-homogeneous Graphs

PubMed Central

2010-01-01

Background Finding the subgraphs of a graph database that are isomorphic to a given query graph has practical applications in several fields, from cheminformatics to image understanding. Since subgraph isomorphism is a computationally hard problem, indexing techniques have been intensively exploited to speed up the process. Such systems filter out those graphs which cannot contain the query, and apply a subgraph isomorphism algorithm to each residual candidate graph. The applicability of such systems is limited to databases of small graphs, because their filtering power degrades on large graphs. Results In this paper, SING (Subgraph search In Non-homogeneous Graphs), a novel indexing system able to cope with large graphs, is presented. The method uses the notion of feature, which can be a small subgraph, subtree or path. Each graph in the database is annotated with the set of all its features. The key point is to make use of feature locality information. This idea is used to both improve the filtering performance and speed up the subgraph isomorphism task. Conclusions Extensive tests on chemical compounds, biological networks and synthetic graphs show that the proposed system outperforms the most popular systems in query time over databases of medium and large graphs. Other specific tests show that the proposed system is effective for single large graphs. PMID:20170516

Isomorphism and solid solutions among Ag- and Au-selenides

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

Palyanova, Galina A.; Seryotkin, Yurii V.; Novosibirsk State University

Au-Ag selenides were synthesized by heating stoichiometric mixtures of elementary substances of initial compositions Ag{sub 2−x}Au{sub x}Se with a step of x=0.25 (0≤x≤2) to 1050 °C and annealing at 500 °C. Scanning electron microscopy, optical microscopy, electron microprobe analysis and X-ray powder diffraction methods have been applied to study synthesized samples. Results of studies of synthesized products revealed the existence of three solid solutions with limited isomorphism Ag↔Au: naumannite Ag{sub 2}Se – Ag{sub 1.94}Au{sub 0.06}Se, fischesserite Ag{sub 3}AuSe{sub 2} - Ag{sub 3.2}Au{sub 0.8}Se{sub 2} and gold selenide AuSe - Au{sub 0.94}Ag{sub 0.06}Se. Solid solutions and AgAuSe phases were added tomore » the phase diagram of Ag-Au-Se system. Crystal-chemical interpretation of Ag-Au isomorphism in selenides was made on the basis of structural features of fischesserite, naumannite, and AuSe. - Highlights: • Au-Ag selenides were synthesized. • Limited Ag-Au isomorphism in the selenides is affected by structural features. • Some new phases were introduced to the phase diagram Ag-Au-Se.« less

The SENSE-Isomorphism Theoretical Image Voxel Estimation (SENSE-ITIVE) Model for Reconstruction and Observing Statistical Properties of Reconstruction Operators

PubMed Central

Bruce, Iain P.; Karaman, M. Muge; Rowe, Daniel B.

2012-01-01

The acquisition of sub-sampled data from an array of receiver coils has become a common means of reducing data acquisition time in MRI. Of the various techniques used in parallel MRI, SENSitivity Encoding (SENSE) is one of the most common, making use of a complex-valued weighted least squares estimation to unfold the aliased images. It was recently shown in Bruce et al. [Magn. Reson. Imag. 29(2011):1267–1287] that when the SENSE model is represented in terms of a real-valued isomorphism, it assumes a skew-symmetric covariance between receiver coils, as well as an identity covariance structure between voxels. In this manuscript, we show that not only is the skew-symmetric coil covariance unlike that of real data, but the estimated covariance structure between voxels over a time series of experimental data is not an identity matrix. As such, a new model, entitled SENSE-ITIVE, is described with both revised coil and voxel covariance structures. Both the SENSE and SENSE-ITIVE models are represented in terms of real-valued isomorphisms, allowing for a statistical analysis of reconstructed voxel means, variances, and correlations resulting from the use of different coil and voxel covariance structures used in the reconstruction processes to be conducted. It is shown through both theoretical and experimental illustrations that the miss-specification of the coil and voxel covariance structures in the SENSE model results in a lower standard deviation in each voxel of the reconstructed images, and thus an artificial increase in SNR, compared to the standard deviation and SNR of the SENSE-ITIVE model where both the coil and voxel covariances are appropriately accounted for. It is also shown that there are differences in the correlations induced by the reconstruction operations of both models, and consequently there are differences in the correlations estimated throughout the course of reconstructed time series. These differences in correlations could result in meaningful differences in interpretation of results. PMID:22617147

A Current Logical Framework: The Propositional Fragment

DTIC Science & Technology

2003-01-01

Under the Curry- Howard isomorphism, M can also be read as a proof term, and A as a proposition of intuitionistic linear logic in its formulation as DILL...the obliga- tion to ensure that the underlying logic (via the Curry- Howard isomorphism, if you like) is sensible. In particular, the principles of...Proceedings of the International Logic Programming Symposium (ILPS󈨣), pages 51-65, Portland, Oregon, December 1995. MIT Press. 6. G. Bellin and P. J

Homology and isomorphism: Bourdieu in conversation with New Institutionalism.

PubMed

Wang, Yingyao

2016-06-01

Bourdieusian Field Theory (BFT) provided decisive inspiration for the early conceptual formulation of New Institutionalism (NI). This paper attempts to reinvigorate the stalled intellectual dialogue between NI and BFT by comparing NI's concept of isomorphism with BFT's notion of homology. I argue that Bourdieu's understanding of domination-oriented social action, transposable habitus, and a non-linear causality, embodied in his neglected concept of homology, provides an alternative theorization of field-level convergence to New Institutionalism's central idea of institutional isomorphism. To showcase how BFT can be useful for organizational research, I postulate a habitus-informed and field-conditioned theory of transference to enrich NI's spin-off thesis of 'diffusion'. I propose that while NI can benefit from BFT's potential of bringing social structure back into organizational research, BFT can enrich its social analysis by borrowing from NI's elaboration of the symbolic system of organizations. © London School of Economics and Political Science 2016.

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

Nekrasov, Nikita; ITEP, Moscow; Shatashvili, Samson

Supersymmetric vacua of two dimensional N = 4 gauge theories with matter, softly broken by the twisted masses down to N = 2, are shown to be in one-to-one correspondence with the eigenstates of integrable spin chain Hamiltonians. Examples include: the Heisenberg SU(2)XXX spin chain which is mapped to the two dimensional U(N) theory with fundamental hypermultiplets, the XXZ spin chain which is mapped to the analogous three dimensional super-Yang-Mills theory compactified on a circle, the XYZ spin chain and eight-vertex model which are related to the four dimensional theory compactified on T{sup 2}. A consequence of our correspondence ismore » the isomorphism of the quantum cohomology ring of various quiver varieties, such as cotangent bundles to (partial) flag varieties and the ring of quantum integrals of motion of various spin chains. The correspondence extends to any spin group, representations, boundary conditions, and inhomogeneity, it includes Sinh-Gordon and non-linear Schroedinger models as well as the dynamical spin chains like Hubbard model. Compactifications of four dimensional N = 2 theories on a two-sphere lead to the instanton-corrected Bethe equations.« less

Expression, purification, crystallization and preliminary crystallographic analysis of MxiH, a subunit of the Shigella flexneri type III secretion system needle

PubMed Central

Deane, Janet E.; Cordes, Frank S.; Roversi, Pietro; Johnson, Steven; Kenjale, Roma; Picking, William D.; Picking, Wendy L.; Lea, Susan M.; Blocker, Ariel

2006-01-01

A monodisperse truncation mutant of MxiH, the subunit of the needle from the Shigella flexneri type III secretion system (TTSS), has been overexpressed and purified. Crystals were grown of native and selenomethionine-labelled MxiHCΔ5 and diffraction data were collected to 1.9 Å resolution. The crystals belong to space group C2, with unit-cell parameters a = 183.4, b = 28.1, c = 27.8 Å, β = 96.5°. An anomalous difference Patterson map calculated with the data from the SeMet-labelled crystals revealed a single peak on the Harker section v = 0. Inspection of a uranyl derivative also revealed one peak in the isomorphous difference Patterson map on the Harker section v = 0. Analysis of the self-rotation function indicates the presence of a twofold non-crystallographic symmetry axis approximately along a. The calculated Matthews coefficient is 1.9 Å3 Da−1 for two molecules per asymmetric unit, corresponding to a solvent content of 33%. PMID:16511329

Expression, purification, crystallization and preliminary crystallographic analysis of MxiH, a subunit of the Shigella flexneri type III secretion system needle.

PubMed

Deane, Janet E; Cordes, Frank S; Roversi, Pietro; Johnson, Steven; Kenjale, Roma; Picking, William D; Picking, Wendy L; Lea, Susan M; Blocker, Ariel

2006-03-01

A monodisperse truncation mutant of MxiH, the subunit of the needle from the Shigella flexneri type III secretion system (TTSS), has been overexpressed and purified. Crystals were grown of native and selenomethionine-labelled MxiH(CDelta5) and diffraction data were collected to 1.9 A resolution. The crystals belong to space group C2, with unit-cell parameters a = 183.4, b = 28.1, c = 27.8 A, beta = 96.5 degrees. An anomalous difference Patterson map calculated with the data from the SeMet-labelled crystals revealed a single peak on the Harker section v = 0. Inspection of a uranyl derivative also revealed one peak in the isomorphous difference Patterson map on the Harker section v = 0. Analysis of the self-rotation function indicates the presence of a twofold non-crystallographic symmetry axis approximately along a. The calculated Matthews coefficient is 1.9 A3 Da(-1) for two molecules per asymmetric unit, corresponding to a solvent content of 33%.

Banach Synaptic Algebras

NASA Astrophysics Data System (ADS)

Foulis, David J.; Pulmannov, Sylvia

2018-04-01

Using a representation theorem of Erik Alfsen, Frederic Schultz, and Erling Størmer for special JB-algebras, we prove that a synaptic algebra is norm complete (i.e., Banach) if and only if it is isomorphic to the self-adjoint part of a Rickart C∗-algebra. Also, we give conditions on a Banach synaptic algebra that are equivalent to the condition that it is isomorphic to the self-adjoint part of an AW∗-algebra. Moreover, we study some relationships between synaptic algebras and so-called generalized Hermitian algebras.

The Rings with Identity Whose Additive Subgroups Are One-Sided Ideals

ERIC Educational Resources Information Center

Dobbs, David E.

2017-01-01

Let R be a ring with identity. Then {0} and R are the only additive subgroups of R if and only if R is isomorphic (as a ring with identity) to (exactly) one of {0}, Z/pZ for a prime number p. Also, each additive subgroup of R is a one-sided ideal of R if and only if R is isomorphic to (exactly) one of {0}, Z, Z/nZ for an integer n = 2. This note…

The Role of Left Occipitotemporal Cortex in Reading: Reconciling Stimulus, Task, and Lexicality Effects

PubMed Central

Humphries, Colin; Desai, Rutvik H.; Seidenberg, Mark S.; Osmon, David C.; Stengel, Ben C.; Binder, Jeffrey R.

2013-01-01

Although the left posterior occipitotemporal sulcus (pOTS) has been called a visual word form area, debate persists over the selectivity of this region for reading relative to general nonorthographic visual object processing. We used high-resolution functional magnetic resonance imaging to study left pOTS responses to combinatorial orthographic and object shape information. Participants performed naming and visual discrimination tasks designed to encourage or suppress phonological encoding. During the naming task, all participants showed subregions within left pOTS that were more sensitive to combinatorial orthographic information than to object information. This difference disappeared, however, when phonological processing demands were removed. Responses were stronger to pseudowords than to words, but this effect also disappeared when phonological processing demands were removed. Subregions within the left pOTS are preferentially activated when visual input must be mapped to a phonological representation (i.e., a name) and particularly when component parts of the visual input must be mapped to corresponding phonological elements (consonant or vowel phonemes). Results indicate a specialized role for subregions within the left pOTS in the isomorphic mapping of familiar combinatorial visual patterns to phonological forms. This process distinguishes reading from picture naming and accounts for a wide range of previously reported stimulus and task effects in left pOTS. PMID:22505661

Nonadiabatic dynamics of photo-induced proton-coupled electron transfer reactions via ring-polymer surface hopping

NASA Astrophysics Data System (ADS)

Shakib, Farnaz; Huo, Pengfei

Photo-induced proton-coupled electron transfer reactions (PCET) are at the heart of energy conversion reactions in photocatalysis. Here, we apply the recently developed ring-polymer surface-hopping (RPSH) approach to simulate the nonadiabatic dynamics of photo-induced PCET. The RPSH method incorporates ring-polymer (RP) quantization of the proton into the fewest-switches surface-hopping (FSSH) approach. Using two diabatic electronic states, corresponding to the electron donor and acceptor states, we model photo-induced PCET with the proton described by a classical isomorphism RP. From the RPSH method, we obtain numerical results that are comparable to those obtained when the proton is treated quantum mechanically. This accuracy stems from incorporating exact quantum statistics, such as proton tunnelling, into approximate quantum dynamics. Additionally, RPSH offers the numerical accuracy along with the computational efficiency. Namely, compared to the FSSH approach in vibronic representation, there is no need to calculate a massive number of vibronic states explicitly. This approach opens up the possibility to accurately and efficiently simulate photo-induced PCET with multiple transferring protons or electrons.

Isomorphism and solid solutions among Ag- and Au-selenides

NASA Astrophysics Data System (ADS)

Palyanova, Galina A.; Seryotkin, Yurii V.; Kokh, Konstantin A.; Bakakin, Vladimir V.

2016-09-01

Au-Ag selenides were synthesized by heating stoichiometric mixtures of elementary substances of initial compositions Ag2-xAuxSe with a step of х=0.25 (0≤х≤2) to 1050 °С and annealing at 500 °C. Scanning electron microscopy, optical microscopy, electron microprobe analysis and X-ray powder diffraction methods have been applied to study synthesized samples. Results of studies of synthesized products revealed the existence of three solid solutions with limited isomorphism Ag↔Au: naumannite Ag2Se - Ag1.94Au0.06Se, fischesserite Ag3AuSe2 - Ag3.2Au0.8Se2 and gold selenide AuSe - Au0.94Ag0.06Se. Solid solutions and AgAuSe phases were added to the phase diagram of Ag-Au-Se system. Crystal-chemical interpretation of Ag-Au isomorphism in selenides was made on the basis of structural features of fischesserite, naumannite, and AuSe.

Explaining the accreditation process from the institutional isomorphism perspective: a case study of Jordanian primary healthcare centers.

PubMed

Alyahya, Mohammad; Hijazi, Heba; Harvey, Heather

2018-01-01

While the main focus of accreditation initiatives has been on hospitals, the implementation of these programs is a relatively new notion among other types of healthcare facilities. Correspondingly, this study aims to understand how accreditation is perceived among primary public healthcare centers using an isomorphic institutional theory. Semi-structured, in-depth interviews were conducted with 56 healthcare professionals and administrative staff from seven non-profit healthcare centers in Jordan using an explanatory case-study approach. The informants' narratives revealed that all three components of institutional theory: coercive, mimetic, and normative pressure, were drivers for institutional change in seeking accreditation. There was an overlapping and blending between the three various types of pressure. While participants perceived that healthcare centers faced formal and informal pressures to achieve accreditation, health centers were reluctant about the time, amount of effort, and their ability to achieve the accreditation. Ambiguity and fear of failure forced them to model successful ones. Moreover, the findings revealed that normative values of health professionals enhanced institutional isomorphism and influenced the accreditation process. Identifying these isomorphic changes may help key stakeholders to develop plans, policies, and procedures that could improve the quality of healthcare and enhance accreditation as an organizational strategic plan. Moreover, the study provided explanations of why and how organizations move to adopt new interventions and grow over time. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Glutathion-S-Transferase P1 polymorphisms association with broncopulmonary dysplasia in preterm infants

PubMed Central

Karagianni, P; Rallis, D; Fidani, L; Porpodi, M; Kalinderi, K; Tsakalidis, C; Nikolaidis, N

2013-01-01

Background: Oxidative stress, characterized by the excretion of pre-oxidative and anti-oxidative proteases, has a key role in the pathogenesis of bronchopulmonary dysplasia (BPD). One of the many host anti-oxidant enzymes is glutathione-S-transferase P1 (GSTP1), with three polymorphic alleles having been identified: homozygous ile, heterozygous ile/val and homozygous val isomorph. The aim of this study was to examine the genetic predisposition to BPD in the GSTP1 polymorphisms. Methods: A prospective case-control study was carried out in the 2nd Neonatal Intensive Care Unit of Aristotle University in Thessaloniki, Greece during 2008. The genetic polymorphisms of GSTP1 in 28 preterms <32 weeks gestational age (GA) with BPD compared to 74 controls (33 preterms without BPD and 41 healthy terms) were examined. Results: The homozygous ile isomorph was predominant in all groups (preterms with BPD: 82%, preterms without BPD: 70%, healthy terms: 78%), followed by the heterozygous ile/val (14%, 18% and 20% respectively) and the homozygous val isomorph (4%, 12% and 2% respectively). The homozygous ile isomorph was also identified in the majority of preterms with mild (80%), moderate (100%) and severe (73%) BPD. The GSTP1 genetic distribution did not differ between the groups and GSTP1 polymorphisms were not associated with the severity of BPD. Conclusions: This study could not confirm an association between GSTP1 polymorphisms and the development of BPD or the severity of the disease. PMID:25031518

Glutathion-S-Transferase P1 polymorphisms association with broncopulmonary dysplasia in preterm infants.

PubMed

Karagianni, P; Rallis, D; Fidani, L; Porpodi, M; Kalinderi, K; Tsakalidis, C; Nikolaidis, N

2013-10-01

Oxidative stress, characterized by the excretion of pre-oxidative and anti-oxidative proteases, has a key role in the pathogenesis of bronchopulmonary dysplasia (BPD). One of the many host anti-oxidant enzymes is glutathione-S-transferase P1 (GSTP1), with three polymorphic alleles having been identified: homozygous ile, heterozygous ile/val and homozygous val isomorph. The aim of this study was to examine the genetic predisposition to BPD in the GSTP1 polymorphisms. A prospective case-control study was carried out in the 2nd Neonatal Intensive Care Unit of Aristotle University in Thessaloniki, Greece during 2008. The genetic polymorphisms of GSTP1 in 28 preterms <32 weeks gestational age (GA) with BPD compared to 74 controls (33 preterms without BPD and 41 healthy terms) were examined. The homozygous ile isomorph was predominant in all groups (preterms with BPD: 82%, preterms without BPD: 70%, healthy terms: 78%), followed by the heterozygous ile/val (14%, 18% and 20% respectively) and the homozygous val isomorph (4%, 12% and 2% respectively). The homozygous ile isomorph was also identified in the majority of preterms with mild (80%), moderate (100%) and severe (73%) BPD. The GSTP1 genetic distribution did not differ between the groups and GSTP1 polymorphisms were not associated with the severity of BPD. This study could not confirm an association between GSTP1 polymorphisms and the development of BPD or the severity of the disease.

Isomorphisms between Petri nets and dataflow graphs

NASA Technical Reports Server (NTRS)

Kavi, Krishna M.; Buckles, Billy P.; Bhat, U. Narayan

1987-01-01

Dataflow graphs are a generalized model of computation. Uninterpreted dataflow graphs with nondeterminism resolved via probabilities are shown to be isomorphic to a class of Petri nets known as free choice nets. Petri net analysis methods are readily available in the literature and this result makes those methods accessible to dataflow research. Nevertheless, combinatorial explosion can render Petri net analysis inoperative. Using a previously known technique for decomposing free choice nets into smaller components, it is demonstrated that, in principle, it is possible to determine aspects of the overall behavior from the particular behavior of components.

Holographic bulk reconstruction with α' corrections

NASA Astrophysics Data System (ADS)

Roy, Shubho R.; Sarkar, Debajyoti

2017-10-01

We outline a holographic recipe to reconstruct α' corrections to anti-de Sitter (AdS) (quantum) gravity from an underlying CFT in the strictly planar limit (N →∞ ). Assuming that the boundary CFT can be solved in principle to all orders of the 't Hooft coupling λ , for scalar primary operators, the λ-1 expansion of the conformal dimensions can be mapped to higher curvature corrections of the dual bulk scalar field action. Furthermore, for the metric perturbations in the bulk, the AdS /CFT operator-field isomorphism forces these corrections to be of the Lovelock type. We demonstrate this by reconstructing the coefficient of the leading Lovelock correction, also known as the Gauss-Bonnet term in a bulk AdS gravity action using the expression of stress-tensor two-point function up to subleading order in λ-1.

The canonical quantization of chaotic maps on the torus

NASA Astrophysics Data System (ADS)

Rubin, Ron Shai

In this thesis, a quantization method for classical maps on the torus is presented. The quantum algebra of observables is defined as the quantization of measurable functions on the torus with generators exp (2/pi ix) and exp (2/pi ip). The Hilbert space we use remains the infinite-dimensional L2/ (/IR, dx). The dynamics is given by a unitary quantum propagator such that as /hbar /to 0, the classical dynamics is returned. We construct such a quantization for the Kronecker map, the cat map, the baker's map, the kick map, and the Harper map. For the cat map, we find the same for the propagator on the plane the same integral kernel conjectured in (HB) using semiclassical methods. We also define a quantum 'integral over phase space' as a trace over the quantum algebra. Using this definition, we proceed to define quantum ergodicity and mixing for maps on the torus. We prove that the quantum cat map and Kronecker map are both ergodic, but only the cat map is mixing, true to its classical origins. For Planck's constant satisfying the integrality condition h = 1/N, with N/in doubz+, we construct an explicit isomorphism between L2/ (/IR, dx) and the Hilbert space of sections of an N-dimensional vector bundle over a θ-torus T2 of boundary conditions. The basis functions are distributions in L2/ (/IR, dx), given by an infinite comb of Dirac δ-functions. In Bargmann space these distributions take on the form of Jacobi ϑ-functions. Transformations from position to momentum representation can be implemented via a finite N-dimensional discrete Fourier transform. With the θ-torus, we provide a connection between the finite-dimensional quantum maps given in the physics literature and the canonical quantization presented here and found in the language of pseudo-differential operators elsewhere in mathematics circles. Specifically, at a fixed point of the dynamics on the θ-torus, we return a finite-dimensional matrix propagator. We present this connection explicitly for several examples.

An Improved Heuristic Method for Subgraph Isomorphism Problem

NASA Astrophysics Data System (ADS)

Xiang, Yingzhuo; Han, Jiesi; Xu, Haijiang; Guo, Xin

2017-09-01

This paper focus on the subgraph isomorphism (SI) problem. We present an improved genetic algorithm, a heuristic method to search the optimal solution. The contribution of this paper is that we design a dedicated crossover algorithm and a new fitness function to measure the evolution process. Experiments show our improved genetic algorithm performs better than other heuristic methods. For a large graph, such as a subgraph of 40 nodes, our algorithm outperforms the traditional tree search algorithms. We find that the performance of our improved genetic algorithm does not decrease as the number of nodes in prototype graphs.

A Symplectic Instanton Homology via Traceless Character Varieties

NASA Astrophysics Data System (ADS)

Horton, Henry T.

Since its inception, Floer homology has been an important tool in low-dimensional topology. Floer theoretic invariants of 3-manifolds tend to be either gauge theoretic or symplecto-geometric in nature, and there is a general philosophy that each gauge theoretic Floer homology should have a corresponding symplectic Floer homology and vice-versa. In this thesis, we construct a Lagrangian Floer invariant for any closed, oriented 3-manifold Y (called the symplectic instanton homology of Y and denoted SI(Y)) which is conjecturally equivalent to a Floer homology defined using a certain variant of Yang-Mills gauge theory. The crucial ingredient for defining SI( Y) is the use of traceless character varieties in the symplectic setting, which allow us to avoid the debilitating technical hurdles present when one attempts to define a symplectic version of instanton Floer homologies. Floer theories are also expected to roughly satisfy the axioms of a topological quantum field theory (TQFT), and furthermore Dehn surgeries on knots should induce exact triangles of Floer homologies. Following a strategy used by Ozsvath and Szabo in the context of Heegaard Floer homology, we prove that our theory is functorial with respect to connected 4-dimensional cobordisms, so that cobordisms induce homomorphisms between symplectic instanton homologies. By studying the effect of Dehn surgeries on traceless character varieties, we establish a surgery exact triangle using work of Seidel that relates the geometry of Lefschetz fibrations with exact triangles in Lagrangian Floer theory. We further prove that Dehn surgeries on a link L in a 3-manifold Y induce a spectral sequence of symplectic instanton homologies - the E2-page is isomorphic to a direct sum of symplectic instanton homologies of all possible combinations of 0- and 1-surgeries on the components of L, and the spectral sequence converges to SI(Y). For the branched double cover Sigma(L) of a link L in S3, we show there is a link surgery spectral sequence whose E 2-page is isomorphic to the reduced Khovanov homology of L and which converges to the symplectic instanton homology of Sigma( L).

Mapping Systemic Risk: Critical Degree and Failures Distribution in Financial Networks.

PubMed

Smerlak, Matteo; Stoll, Brady; Gupta, Agam; Magdanz, James S

2015-01-01

The financial crisis illustrated the need for a functional understanding of systemic risk in strongly interconnected financial structures. Dynamic processes on complex networks being intrinsically difficult to model analytically, most recent studies of this problem have relied on numerical simulations. Here we report analytical results in a network model of interbank lending based on directly relevant financial parameters, such as interest rates and leverage ratios. We obtain a closed-form formula for the "critical degree" (the number of creditors per bank below which an individual shock can propagate throughout the network), and relate failures distributions to network topologies, in particular scalefree ones. Our criterion for the onset of contagion turns out to be isomorphic to the condition for cooperation to evolve on graphs and social networks, as recently formulated in evolutionary game theory. This remarkable connection supports recent calls for a methodological rapprochement between finance and ecology.

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

Caruso, M., E-mail: mcaruso@ugr.es; Fanchiotti, H.; Canal, C.A. Garcia

An equivalence between the Schroedinger dynamics of a quantum system with a finite number of basis states and a classical dynamics is presented. The equivalence is an isomorphism that connects in univocal way both dynamical systems. We treat the particular case of neutral kaons and found a class of electric networks uniquely related to the kaon system finding the complete map between the matrix elements of the effective Hamiltonian of kaons and those elements of the classical dynamics of the networks. As a consequence, the relevant {epsilon} parameter that measures CP violation in the kaon system is completely determined inmore » terms of network parameters. - Highlights: > We provide a formal equivalence between classical and quantum dynamics. > We make use of the decomplexification concept. > Neutral kaon systems can be represented by electric circuits. > CP symmetry violation can be taken into account by non-reciprocity. > Non-reciprocity is represented by gyrators.« less

Isomorphism of dimer configurations and spanning trees on finite square lattices

NASA Astrophysics Data System (ADS)

Brankov, J. G.

1995-09-01

One-to-one mappings of the close-packed dimer configurations on a finite square lattice with free boundaries L onto the spanning trees of a related graph (or two-graph) G are found. The graph (two-graph) G can be constructed from L by: (1) deleting all the vertices of L with arbitrarily fixed parity of the row and column numbers; (2) suppressing all the vertices of degree 2 except those of degree 2 in L; (3) merging all the vertices of degree 1 into a single vertex g. The matrix Kirchhoff theorem reduces the enumeration problem for the spanning trees on G to the eigenvalue problem for the discrete Laplacian on the square lattice L'=G g with mixed Dirichlet-Neumann boundary conditions in at least one direction. That fact explains some of the unusual finite-size properties of the dimer model.

Mapping Systemic Risk: Critical Degree and Failures Distribution in Financial Networks

PubMed Central

Smerlak, Matteo; Stoll, Brady; Gupta, Agam; Magdanz, James S.

2015-01-01

The financial crisis illustrated the need for a functional understanding of systemic risk in strongly interconnected financial structures. Dynamic processes on complex networks being intrinsically difficult to model analytically, most recent studies of this problem have relied on numerical simulations. Here we report analytical results in a network model of interbank lending based on directly relevant financial parameters, such as interest rates and leverage ratios. We obtain a closed-form formula for the “critical degree” (the number of creditors per bank below which an individual shock can propagate throughout the network), and relate failures distributions to network topologies, in particular scalefree ones. Our criterion for the onset of contagion turns out to be isomorphic to the condition for cooperation to evolve on graphs and social networks, as recently formulated in evolutionary game theory. This remarkable connection supports recent calls for a methodological rapprochement between finance and ecology. PMID:26207631

Differential operators on the supercircle S1|2 and symbol map

NASA Astrophysics Data System (ADS)

Hamza, Raouafi; Selmi, Zeineb; Boujelben, Jamel

2017-09-01

We consider the supercircle S1|2 equipped with the standard contact structure. The conformal Lie superalgebra 𝒦(2) acts on S1|2 as the Lie superalgebra of contact vector fields; it contains the Möbius superalgebra 𝔬𝔰𝔭(2|2). We study the space of linear differential operators on weighted densities as a module over 𝔬𝔰𝔭(2|2). We introduce the canonical isomorphism between this space and the corresponding space of symbols. This result allows us to give, in contrast to the classical setting, a classification of the 𝒦(2)-modules 𝔇λ,μk of linear differential operators of order k acting on the superspaces of weighted densities. This work is the simplest superization of a result by Gargoubi and Ovsienko [Modules of differential operators on the real line, Funct. Anal. Appl. 35(1) (2001) 13-18.

A stochastic model for tumor geometry evolution during radiation therapy in cervical cancer

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

Liu, Yifang; Lee, Chi-Guhn; Chan, Timothy C. Y., E-mail: tcychan@mie.utoronto.ca

2014-02-15

Purpose: To develop mathematical models to predict the evolution of tumor geometry in cervical cancer undergoing radiation therapy. Methods: The authors develop two mathematical models to estimate tumor geometry change: a Markov model and an isomorphic shrinkage model. The Markov model describes tumor evolution by investigating the change in state (either tumor or nontumor) of voxels on the tumor surface. It assumes that the evolution follows a Markov process. Transition probabilities are obtained using maximum likelihood estimation and depend on the states of neighboring voxels. The isomorphic shrinkage model describes tumor shrinkage or growth in terms of layers of voxelsmore » on the tumor surface, instead of modeling individual voxels. The two proposed models were applied to data from 29 cervical cancer patients treated at Princess Margaret Cancer Centre and then compared to a constant volume approach. Model performance was measured using sensitivity and specificity. Results: The Markov model outperformed both the isomorphic shrinkage and constant volume models in terms of the trade-off between sensitivity (target coverage) and specificity (normal tissue sparing). Generally, the Markov model achieved a few percentage points in improvement in either sensitivity or specificity compared to the other models. The isomorphic shrinkage model was comparable to the Markov approach under certain parameter settings. Convex tumor shapes were easier to predict. Conclusions: By modeling tumor geometry change at the voxel level using a probabilistic model, improvements in target coverage and normal tissue sparing are possible. Our Markov model is flexible and has tunable parameters to adjust model performance to meet a range of criteria. Such a model may support the development of an adaptive paradigm for radiation therapy of cervical cancer.« less

Second look at the spread of epidemics on networks

NASA Astrophysics Data System (ADS)

Kenah, Eben; Robins, James M.

2007-09-01

In an important paper, Newman [Phys. Rev. E66, 016128 (2002)] claimed that a general network-based stochastic Susceptible-Infectious-Removed (SIR) epidemic model is isomorphic to a bond percolation model, where the bonds are the edges of the contact network and the bond occupation probability is equal to the marginal probability of transmission from an infected node to a susceptible neighbor. In this paper, we show that this isomorphism is incorrect and define a semidirected random network we call the epidemic percolation network that is exactly isomorphic to the SIR epidemic model in any finite population. In the limit of a large population, (i) the distribution of (self-limited) outbreak sizes is identical to the size distribution of (small) out-components, (ii) the epidemic threshold corresponds to the phase transition where a giant strongly connected component appears, (iii) the probability of a large epidemic is equal to the probability that an initial infection occurs in the giant in-component, and (iv) the relative final size of an epidemic is equal to the proportion of the network contained in the giant out-component. For the SIR model considered by Newman, we show that the epidemic percolation network predicts the same mean outbreak size below the epidemic threshold, the same epidemic threshold, and the same final size of an epidemic as the bond percolation model. However, the bond percolation model fails to predict the correct outbreak size distribution and probability of an epidemic when there is a nondegenerate infectious period distribution. We confirm our findings by comparing predictions from percolation networks and bond percolation models to the results of simulations. In the Appendix, we show that an isomorphism to an epidemic percolation network can be defined for any time-homogeneous stochastic SIR model.

Gopakumar-Vafa Invariants Do Not Determine Flops

NASA Astrophysics Data System (ADS)

Brown, Gavin; Wemyss, Michael

2017-11-01

Two 3-fold flops are exhibited, both of which have precisely one flopping curve. One of the two flops is new and is distinct from all known algebraic D 4-flops. It is shown that the two flops are neither algebraically nor analytically isomorphic, yet their curve-counting Gopakumar-Vafa invariants are the same. We further show that the contraction algebras associated to both are not isomorphic, so the flops are distinguished at this level. This shows that the contraction algebra is a finer invariant than various curve-counting theories, and it also provides more evidence for the proposed analytic classification of 3-fold flops via contraction algebras.

Super (a, d)-Cycle-Antimagic Total Labeling on Triangular Ladder Graph and Generalized Jahangir Graph

NASA Astrophysics Data System (ADS)

Roswitha, Mania; Amanda, Anna; Sri Martini, Titin; Winarno, Bowo

2017-06-01

Let G(V (G), E(G)) be a finite simple graph with |V (G)| = G and |E(G)| = eG . Let H be a subgraph of G. The graph G is said to be (a, d)-H-antimagic covering if every edge in G belongs to at least one of the subgraphs G isomorphic to H and there is a bijective function ξ : V ∪ E → {1, 2, …,νG + eG } such that all subgraphs H‧ isomorphic to H, the H‧ -weights w(H‧)=∑v∈V(H‧)ξ(v)+∑e∈E(H‧)ξ(e) constitutes an arithmetic progression {a, a + d, a + 2d, …, a + (t - 1)d}, where a and d are positive integers and t is the number of subgraphs G isomorphic to H. Such a labeling is called super if the vertices contain the smallest possible labels. This research provides super (a, d)-C 3-antimagic total labelng on triangular ladder TLn for n ≥ 2 and super (a, d)-C s+2-antimagic total labeling on generalized Jahangir Jk,s for k ≥ 2 and s ≥ 2.

The new electromagnetic tetrads, infinite tetrad nesting and the non-trivial emergence of complex numbers in real theories of gravitation

NASA Astrophysics Data System (ADS)

Garat, Alcides

How complex numbers get into play in a non-trivial way in real theories of gravitation is relevant since in a unified structure they should be able to relate in a natural way with quantum theories. For a long time this issue has been lingering on both relativistic formulations and quantum theories. We will analyze this fundamental subject under the light of new group isomorphism theorems linking local internal groups of transformations and local groups of spacetime transformations. The bridge between these two kinds of transformations is represented by new tetrads introduced previously. It is precisely through these local tetrad structures that we will provide a non-trivial answer to this old issue. These new tetrads have two fundamental building components, the skeletons and the gauge vectors. It is these constructive elements that provide the mathematical support that allows to prove group isomorphism theorems. In addition to this, we will prove a unique new property, the infinite tetrad nesting, alternating the nesting with non-Abelian tetrads in the construction of the tetrad gauge vectors. As an application we will demonstrate an alternative proof of a new group isomorphism theorem.

On the generality of the topological theory of visual shape perception.

PubMed

Kanbe, Fumio

2013-01-01

This study used a series of six closely related experiments to examine whether individuals use topological structures to discriminate figures. Strict control was exerted over the selection of stimuli, which were a specific type of randomly generated lined figures that can be classified using isomorphic sets defined by graph theory. Any two figures within an isomorphic set possessed the same topological structure. The experiments described here used a same/different discrimination task with simultaneously presented pairs of figures: (a) identical pairs (Id pairs), in which each pair of figures had the same topological and superficial properties; (b) nonidentical and isomorphic pairs (Iso pairs), in which each pair had the same topological but different superficial properties; and (c) nonidentical and nonisomorphic pairs (Noniso pairs), in which each pair had different topological properties. Within these experiments I varied the conditions related to the intersecting line segments, presentation of points defining each figure, figure complexity, stimulus aspect ratios, and the parity of the total line-segment lengths between the figures in each pair. These variations showed that the latencies for making accurate discriminations were shorter for Noniso pairs than for Iso pairs, suggesting that individuals are sensitive to topology when distinguishing figures.

Super (a,d)-H-antimagic covering of möbius ladder graph

NASA Astrophysics Data System (ADS)

Indriyani, Novia; Sri Martini, Titin

2018-04-01

Let G = (V(G), E(G)) be a simple graph. Let H-covering of G is a subgraph H 1, H 2, …, Hj with every edge in G is contained in at least one graph Hi for 1 ≤ i ≤ j. If every Hi is isomorphic, then G admits an H-covering. Furthermore, an (a,d)-H-antimagic covering if there bijective function ξ :V(G)\\cup E(G)\\to \\{1,2,3,\\ldots,|V(G)|+|E(G)|\\}. The H‑-weights for all subgraphs H‑ isomorphic to H ω ({H}^{\\prime })={\\sum }v\\in V({H^{\\prime })}ξ (v)+{\\sum }e\\in E({H^{\\prime })}ξ (e). The weights of subgraphs constitutes an arithmatic progression {a, a + d, …, a + (t ‑ 1)d} where a and d are positive integers and t is the number of subgraphs G isomorphic to H. If ξ (V(G))=\\{1,2,\\ldots,|V(G)|\\} then ξ is called super (a, d)-H-antimagic covering. The research provides super (a, d)-H-antimagic covering with d = {1, 3} of Möbius ladder graph Mn for n > 5 and n is odd.

Modification of the crystal habit of celecoxib for improved processability.

PubMed

Banga, Sheere; Chawla, Garima; Varandani, Deepak; Mehta, B R; Bansal, Arvind K

2007-01-01

Crystallization is often used in the pharmaceutical industry for purification and isolation of drugs, and also as a means of generating polymorphs or isomorphs. The aim of this study was to investigate the role of extrinsic crystallization parameters on the crystallized product, with special emphasis on improving the mechanical properties of acicular celecoxib. Celecoxib isomorphs were prepared using different techniques (solvent crystallization and vapour diffusion) and crystallization conditions (solvents, stirring, degree of supersaturation, crystallization temperature and seeding). Powder X-ray diffractometry, spectroscopic and thermal methods were used to investigate physical characteristics of crystals. Growth kinetics and aggregation dynamics of crystallization in polar and non-polar solvents were simulated using a dynamic light scattering method. The quick appearance of broad peaks over the range of 10-8000 nm in chloroform during crystallization simulation studies indicated faster aggregation in non-polar solvents. Aspect ratio, flow, compressibility and surface area of recrystallized products were also determined. Surface topography was determined by atomic force microscopy and the lath-shaped crystals (aspect ratio of 2-4) exhibited a roughness index of 1.79 in comparison with 2.92 for needles. Overall, the lath-shaped isomorphs exhibited improved flow and better compressibility.

CombiMotif: A new algorithm for network motifs discovery in protein-protein interaction networks

NASA Astrophysics Data System (ADS)

Luo, Jiawei; Li, Guanghui; Song, Dan; Liang, Cheng

2014-12-01

Discovering motifs in protein-protein interaction networks is becoming a current major challenge in computational biology, since the distribution of the number of network motifs can reveal significant systemic differences among species. However, this task can be computationally expensive because of the involvement of graph isomorphic detection. In this paper, we present a new algorithm (CombiMotif) that incorporates combinatorial techniques to count non-induced occurrences of subgraph topologies in the form of trees. The efficiency of our algorithm is demonstrated by comparing the obtained results with the current state-of-the art subgraph counting algorithms. We also show major differences between unicellular and multicellular organisms. The datasets and source code of CombiMotif are freely available upon request.

Atiyah classes and dg-Lie algebroids for matched pairs

NASA Astrophysics Data System (ADS)

Batakidis, Panagiotis; Voglaire, Yannick

2018-01-01

For every Lie pair (L , A) of algebroids we construct a dg-manifold structure on the Z-graded manifold M = L [ 1 ] ⊕ L / A such that the inclusion ι : A [ 1 ] → M and the projection p : M → L [ 1 ] are morphisms of dg-manifolds. The vertical tangent bundle Tp M then inherits a structure of dg-Lie algebroid over M. When the Lie pair comes from a matched pair of Lie algebroids, we show that the inclusion ι induces a quasi-isomorphism that sends the Atiyah class of this dg-Lie algebroid to the Atiyah class of the Lie pair. We also show how (Atiyah classes of) Lie pairs and dg-Lie algebroids give rise to (Atiyah classes of) dDG-algebras.

Quantum field theory and the linguistic Minimalist Program: a remarkable isomorphism

NASA Astrophysics Data System (ADS)

Piattelli-Palmarini, M.; Vitiello, G.

2017-08-01

By resorting to recent results, we show that an isomorphism exist between linguistic features of the Minimalist Program and the quantum field theory formalism of condensed matter physics. Specific linguistic features which admit a representation in terms of the many-body algebraic formalism are the unconstrained nature of recursive Merge, the operation of the Labeling Algorithm, the difference between pronounced and un-pronounced copies of elements in a sentence and the build-up of the Fibonacci sequence in the syntactic derivation of sentence structures. The collective dynamical nature of the formation process of Logical Forms leading to the individuation of the manifold of concepts and the computational self-consistency of languages are also discussed.

General Syntheses of Nanotubes Induced by Block Copolymer Self-Assembly.

PubMed

Zhao, Jianming; Huang, Wei; Si, Pengchao; Ulstrup, Jens; Diao, Fangyuan; Zhang, Jingdong

2018-06-01

Amphiphilic block copolymer templating strategies are extensively used for syntheses of mesoporous materials. However, monodisperse tubular nanostructures are limited. Here, a general method is developed to synthesize monodisperse nanotubes with narrow diameter distribution induced by self-assembly of block copolymer. 3-Aminophenol (AP) and formaldehyde (F) polymerize and self-assemble with cylindrical PS-b-PEO micelles into worm-like PS-b-PEO@APF composites with uniform diameter (49 ± 3 nm). After template extraction, worm-like APF polymer nanotubes are formed. The structure and morphology of the polymer nanotubes can be tuned by regulating the synthesis conditions. Furthermore, PS-b-PEO@APF composites are uniformly converted to isomorphic carbon nanotubes with large surface area of 662 m 2 g -1 , abundant hierarchical porous frameworks and nitrogen doping. The synthesis can be extended to silica nanotubes. These findings open an avenue to the design of porous materials with controlled structural framework, composition, and properties for a wide range of applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The shape of novel objects contributes to shared impressions.

PubMed

Kurosu, Aaron; Todorov, Alexander

2017-11-01

How do people share impressions of novel objects, and is this even possible? We tested whether the shape of novel 3-D objects can lead to similar impressions across people. To do this, we introduced a technique for manipulating highly complex shapes and measured four types of evaluative impressions (approachable, dangerous, beautiful, likable). Because relatively little is understood regarding how people form impressions of novel objects, we first sought to confirm the reliability of this behavior by examining how similar impressions are for an individual asked to re-evaluate the stimuli (i.e., impression consistency). To situate the magnitude of reliability, we compared novel objects to faces-familiar and extensively studied stimuli. Impression consistency was always present for both types of stimuli and comparable across all evaluations. Second, and more importantly, we tested how similar impressions are across people (i.e., impression consensus). Impression consensus was always present for faces, but not always for novel objects. In Study 2 we examined a greater diversity of shapes and replicated the findings of Study 1 for novel objects. The findings suggest that impression consensus for novel objects only emerges when certain types of shapes and evaluations map together. When such mapping is possible, impressions are isomorphic with the parametrized shapes.

REGULATION OF GEOGRAPHIC VARIABILITY IN HAPLOID:DIPLOD RATIOS OF BIPHASIC SEAWEED LIFE CYCLES(1).

PubMed

da Silva Vieira, Vasco Manuel Nobre de Carvalho; Santos, Rui Orlando Pimenta

2012-08-01

The relative abundance of haploid and diploid individuals (H:D) in isomorphic marine algal biphasic cycles varies spatially, but only if vital rates of haploid and diploid phases vary differently with environmental conditions (i.e. conditional differentiation between phases). Vital rates of isomorphic phases in particular environments may be determined by subtle morphological or physiological differences. Herein, we test numerically how geographic variability in H:D is regulated by conditional differentiation between isomorphic life phases and the type of life strategy of populations (i.e. life cycles dominated by reproduction, survival or growth). Simulation conditions were selected using available data on H:D spatial variability in seaweeds. Conditional differentiation between ploidy phases had a small effect on the H:D variability for species with life strategies that invest either in fertility or in growth. Conversely, species with life strategies that invest mainly in survival, exhibited high variability in H:D through a conditional differentiation in stasis (the probability of staying in the same size class), breakage (the probability of changing to a smaller size class) or growth (the probability of changing to a bigger size class). These results were consistent with observed geographic variability in H:D of natural marine algae populations. © 2012 Phycological Society of America.

Isomorphism and external support in conflicting institutional environments: a study of drug abuse treatment units.

PubMed

D'Aunno, T; Sutton, R I; Price, R H

1991-09-01

Using institutional theory, we developed predictions about organizational units that moved from an environment making consistent demands to one making conflicting demands. Many community mental health centers have diversified into drug abuse treatment. The units providing those services face conflicting demands from the traditional mental health sector and the new drug abuse treatment sector about which clients to serve, how to assess their problems, and who should provide treatment. We propose that in response to such demands these units will adopt apparently conflicting practices. Also, isomorphism with the traditional sector will be positively associated with external support from parent mental health centers and other actors in the mental health sector. Results generally support those predictions.

Structural changes in the oxygen-evolving complex of photosystem II induced by the S 1 to S 2 transition: A combined XRD and QM/MM study

DOE PAGES

Askerka, Mikhail; Wang, Jimin; Brudvig, Gary W.; ...

2014-10-27

The S 1 → S 2 transition of the oxygen-evolving complex (OEC) of photosystem II does not involve the transfer of a proton to the lumen and occurs at cryogenic temperatures. Therefore, it is commonly thought to involve only Mn oxidation without any significant change in the structure of the OEC. Here, we analyze structural changes upon the S 1 → S 2 transition, as revealed by quantum mechanics/molecular mechanics methods and the isomorphous difference Fourier method applied to serial femtosecond X-ray diffraction data. Lastly, we find that the main structural change in the OEC is in the position ofmore » the dangling Mn and its coordination environment.« less

Reflection Functor in the Representation Theory of Preprojective Algebras for Quivers and Integrable Systems

NASA Astrophysics Data System (ADS)

Silantyev, A. V.

2018-05-01

A brief overview of the representation theory of quivers and the associated (deformed) preprojective algebras, as well as of the theories of moduli spaces of these algebras, quiver varieties and a reflection functor, is given. It is proven that a bijection between moduli spaces (in particular, between quiver varieties), which is induced by a reflection function, is the isomorphism of symplectic affine varieties. The Hamiltonian systems on quiver varieties are defined, and the application of a reflection functor to them is described. The review of [1], concerning the case of a cyclic quiver is given, and a role of the reflection functor in this case is clarified. The "spin" integrable generalizations of Calogero-Moser systems and their application to the KP hierarchy generalizations are described.

Pediatric Autoimmune Disorders Associated with Streptococcal Infections and Tourette's Syndrome in Preclinical Studies

PubMed Central

Spinello, Chiara; Laviola, Giovanni; Macrì, Simone

2016-01-01

Accumulating evidence suggests that Tourette's Syndrome (TS) – a multifactorial pediatric disorder characterized by the recurrent exhibition of motor tics and/or vocal utterances – can partly depend on immune dysregulation provoked by early repeated streptococcal infections. The natural and adaptive antibody-mediated reaction to streptococcus has been proposed to potentially turn into a pathological autoimmune response in vulnerable individuals. Specifically, in conditions of increased permeability of the blood brain barrier (BBB), streptococcus-induced antibodies have been proposed to: (i) reach neuronal targets located in brain areas responsible for motion control; and (ii) contribute to the exhibition of symptoms. This theoretical framework is supported by indirect evidence indicating that a subset of TS patients exhibit elevated streptococcal antibody titers upon tic relapses. A systematic evaluation of this hypothesis entails preclinical studies providing a proof of concept of the aforementioned pathological sequelae. These studies shall rest upon individuals characterized by a vulnerable immune system, repeatedly exposed to streptococcus, and carefully screened for phenotypes isomorphic to the pathological signs of TS observed in patients. Preclinical animal models may thus constitute an informative, useful tool upon which conducting targeted, hypothesis-driven experiments. In the present review we discuss the available evidence in preclinical models in support of the link between TS and pediatric autoimmune neuropsychiatric disorders associated with streptococcus infections (PANDAS), and the existing gaps that future research shall bridge. Specifically, we report recent preclinical evidence indicating that the immune responses to repeated streptococcal immunizations relate to the occurrence of behavioral and neurological phenotypes reminiscent of TS. By the same token, we discuss the limitations of these studies: limited evidence of behavioral phenotypes isomorphic to tics and scarce knowledge about the immunological phenomena favoring the transition from natural adaptive immunity to pathological outcomes. PMID:27445678

Evidence That Calls-Based and Mobility Networks Are Isomorphic

PubMed Central

Coscia, Michele; Hausmann, Ricardo

2015-01-01

Social relations involve both face-to-face interaction as well as telecommunications. We can observe the geography of phone calls and of the mobility of cell phones in space. These two phenomena can be described as networks of connections between different points in space. We use a dataset that includes billions of phone calls made in Colombia during a six-month period. We draw the two networks and find that the call-based network resembles a higher order aggregation of the mobility network and that both are isomorphic except for a higher spatial decay coefficient of the mobility network relative to the call-based network: when we discount distance effects on the call connections with the same decay observed for mobility connections, the two networks are virtually indistinguishable. PMID:26713730

Atomic Layer Deposition of Metastable β-Fe 2 O 3 via Isomorphic Epitaxy for Photoassisted Water Oxidation

DOE PAGES

Emery, Jonathan D.; Schlepütz, Christian M.; Guo, Peijun; ...

2014-12-09

Here, we report the growth and photoelectrochemical (PEC) characterization of the uncommon bibyite phase of iron(III) oxide (β-Fe 2O 3) epitaxially stabilized via atomic layer deposition on an conductive, transparent, and isomorphic template (Sn-doped In 2O 3). Furthermore, as a photoanode, unoptimized β-Fe 2O 3 ultrathin films perform similarly to their ubiquitous α-phase (hematite) counterpart, but reveal a more ideal bandgap (1.8 eV), a ~0.1 V improved photocurrent onset potential, and longer wavelength (>600 nm) spectral response. Finally, stable operation under basic water oxidation justifies further exploration of this atypical phase and motivates the investigation of other unexplored metastable phasesmore » as new PEC materials.« less

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

Ponomarenko, Nina S.; Li, Liang; Marino, Antony R.

Heterodimer mutant reaction centers (RCs) of Blastochloris viridis were crystallized using microfluidic technology. In this mutant, a leucine residue replaced the histidine residue which had acted as a fifth ligand to the bacteriochlorophyll (BChl) of the primary electron donor dimer M site (HisM200). With the loss of the histidine-coordinated Mg, one bacteriochlorophyll of the special pair was converted into a bacteriopheophytin (BPhe), and the primary donor became a heterodimer supermolecule. The crystals had dimensions 400 x 100 x 100 {micro}m, belonged to space group P4{sub 3}2{sub 1}2, and were isomorphous to the ones reported earlier for the wild type (WT)more » strain. The structure was solved to a 2.5 {angstrom} resolution limit. Electron-density maps confirmed the replacement of the histidine residue and the absence of Mg. Structural changes in the heterodimer mutant RC relative to the WT included the absence of the water molecule that is typically positioned between the M side of the primary donor and the accessory BChl, a slight shift in the position of amino acids surrounding the site of the mutation, and the rotation of the M194 phenylalanine. The cytochrome subunit was anchored similarly as in the WT and had no detectable changes in its overall position. The highly conserved tyrosine L162, located between the primary donor and the highest potential heme C{sub 380}, revealed only a minor deviation of its hydroxyl group. Concomitantly to modification of the BChl molecule, the redox potential of the heterodimer primary donor increased relative to that of the WT organism (772 mV vs. 517 mV). The availability of this heterodimer mutant and its crystal structure provides opportunities for investigating changes in light-induced electron transfer that reflect differences in redox cascades.« less

Solitons on Noncommutative Torus as Elliptic Calogero-Gaudin Models, Branes and Laughlin Wave Functions

NASA Astrophysics Data System (ADS)

Hou, Bo-Yu; Peng, Dan-Tao; Shi, Kang-Jie; Yue, Rui-Hong

For the noncommutative torus T, in the case of the noncommutative parameter θ = (Z)/(n), we construct the basis of Hilbert space Hn in terms of θ functions of the positions zi of n solitons. The wrapping around the torus generates the algebra An, which is the Zn × Zn Heisenberg group on θ functions. We find the generators g of a local elliptic su(n), which transform covariantly by the global gauge transformation of An. By acting on Hn we establish the isomorphism of An and g. We embed this g into the L-matrix of the elliptic Gaudin and Calogero-Moser models to give the dynamics. The moment map of this twisted cotangent sunT) bundle is matched to the D-equation with the Fayet-Illiopoulos source term, so the dynamics of the noncommutative solitons become that of the brane. The geometric configuration (k, u) of the spectral curve det|L(u) - k| = 0 describes the brane configuration, with the dynamical variables zi of the noncommutative solitons as the moduli T⊗ n/Sn. Furthermore, in the noncommutative Chern-Simons theory for the quantum Hall effect, the constrain equation with quasiparticle source is identified also with the moment map equation of the noncommutative sunT cotangent bundle with marked points. The eigenfunction of the Gaudin differential L-operators as the Laughlin wave function is solved by Bethe ansatz.

Isomorphic Properties of Atoms, Molecules, Water, DNA, Crystals, Earth, SolarSystem and Galaxies

NASA Astrophysics Data System (ADS)

Gareev, F. A.; Gareeva, G. F.; Zhidkova, I. E.

2009-03-01

We discuss the cooperative resonance synchronization enhancement mechanisms of Low Energy Nuclear Reactions (LENR). Some of the low energy external fields can be used as triggers for starting and enhancing exothermic LENR. Any external field shortening distances between protons in nuclei and electrons in atoms should enhance beta-decay (capture) or double-beta decay (capture). We have proposed a new mechanism of LENR: cooperative resonance synchronization processes in the whole system nuclei+atoms+condensed matter+gaseuos+plasma medium, which we suggest can occur at a smaller threshold than the corresponding ones on free constituents. The cooperative processes can be induced and enhanced by low energy external fields. The excess heat is the emission of internal energy, and transmutations at LENR are the result of redistribution inner energy of the whole system.

Geometric Theory of Reduction of Nonlinear Control Systems

NASA Astrophysics Data System (ADS)

Elkin, V. I.

2018-02-01

The foundations of a differential geometric theory of nonlinear control systems are described on the basis of categorical concepts (isomorphism, factorization, restrictions) by analogy with classical mathematical theories (of linear spaces, groups, etc.).

T-duality of singular spacetime compactifications in an H-flux

NASA Astrophysics Data System (ADS)

Linshaw, Andrew; Mathai, Varghese

2018-07-01

We begin by presenting a symmetric version of the circle equivariant T-duality result in a joint work of the second author with Siye Wu, thereby generalizing the results there. We then initiate the study of twisted equivariant Courant algebroids and equivariant generalized geometry and apply it to our context. As before, T-duality exchanges type IIA and type IIB string theories. In our theory, both spacetime and the T-dual spacetime can be singular spaces when the fixed point set is non-empty; the singularities correspond to Kaluza-Klein monopoles. We propose that the Ramond-Ramond charges of type II string theories on the singular spaces are classified by twisted equivariant cohomology groups, consistent with the previous work of Mathai and Wu, and prove that they are naturally isomorphic. We also establish the corresponding isomorphism of twisted equivariant Courant algebroids.

Matching CCD images to a stellar catalog using locality-sensitive hashing

NASA Astrophysics Data System (ADS)

Liu, Bo; Yu, Jia-Zong; Peng, Qing-Yu

2018-02-01

The usage of a subset of observed stars in a CCD image to find their corresponding matched stars in a stellar catalog is an important issue in astronomical research. Subgraph isomorphic-based algorithms are the most widely used methods in star catalog matching. When more subgraph features are provided, the CCD images are recognized better. However, when the navigation feature database is large, the method requires more time to match the observing model. To solve this problem, this study investigates further and improves subgraph isomorphic matching algorithms. We present an algorithm based on a locality-sensitive hashing technique, which allocates quadrilateral models in the navigation feature database into different hash buckets and reduces the search range to the bucket in which the observed quadrilateral model is located. Experimental results indicate the effectivity of our method.

Smiles2Monomers: a link between chemical and biological structures for polymers.

PubMed

Dufresne, Yoann; Noé, Laurent; Leclère, Valérie; Pupin, Maude

2015-01-01

The monomeric composition of polymers is powerful for structure comparison and synthetic biology, among others. Many databases give access to the atomic structure of compounds but the monomeric structure of polymers is often lacking. We have designed a smart algorithm, implemented in the tool Smiles2Monomers (s2m), to infer efficiently and accurately the monomeric structure of a polymer from its chemical structure. Our strategy is divided into two steps: first, monomers are mapped on the atomic structure by an efficient subgraph-isomorphism algorithm ; second, the best tiling is computed so that non-overlapping monomers cover all the structure of the target polymer. The mapping is based on a Markovian index built by a dynamic programming algorithm. The index enables s2m to search quickly all the given monomers on a target polymer. After, a greedy algorithm combines the mapped monomers into a consistent monomeric structure. Finally, a local branch and cut algorithm refines the structure. We tested this method on two manually annotated databases of polymers and reconstructed the structures de novo with a sensitivity over 90 %. The average computation time per polymer is 2 s. s2m automatically creates de novo monomeric annotations for polymers, efficiently in terms of time computation and sensitivity. s2m allowed us to detect annotation errors in the tested databases and to easily find the accurate structures. So, s2m could be integrated into the curation process of databases of small compounds to verify the current entries and accelerate the annotation of new polymers. The full method can be downloaded or accessed via a website for peptide-like polymers at http://bioinfo.lifl.fr/norine/smiles2monomers.jsp.Graphical abstract:.

2+1 black hole with SU(2) hair (and the theory where it grows)

NASA Astrophysics Data System (ADS)

Zanelli, Jorge

2015-04-01

A black hole solution in three spacetime dimensions, endowed with an SU(2) charge is presented. The construction is based on two main features of three dimensions: i) AdS3 spacetime is locally Lorentz-flat, that is, it can be covered with a congruence of local inertial observers, just like flat Minkowski space; ii) The SO(2,1) and SU(2) groups are isomorphic, so that a flat connection of the first can be mapped to a flat connection of the second. The global nontrivial nature of the solution is a consequence of the topology produced by the identification in the covering space that gives rise to the 2+1 black hole. It can be seen that this solution belongs to the vacuum (matter-free) sector of a supersymmetric theory based on the Chern-Simons action for the su(1, 2|2) superalgebra. The action for this system matches that of graphene in the long wavelength limit near the Dirac point. The SU(2) gauge symmetry is interpreted as the freedom to choose locally the definition of spin quantization axis for the electrons.

Rings of h-deformed differential operators

NASA Astrophysics Data System (ADS)

Ogievetsky, O. V.; Herlemont, B.

2017-08-01

We describe the center of the ring Diff h ( n) of h- deformed differential operators of type A. We establish an isomorphism between certain localizations of Diff h ( n) and the Weyl algebra W n , extended by n indeterminates.

Braided Categories of Endomorphisms as Invariants for Local Quantum Field Theories

NASA Astrophysics Data System (ADS)

Giorgetti, Luca; Rehren, Karl-Henning

2018-01-01

We want to establish the "braided action" (defined in the paper) of the DHR category on a universal environment algebra as a complete invariant for completely rational chiral conformal quantum field theories. The environment algebra can either be a single local algebra, or the quasilocal algebra, both of which are model-independent up to isomorphism. The DHR category as an abstract structure is captured by finitely many data (superselection sectors, fusion, and braiding), whereas its braided action encodes the full dynamical information that distinguishes models with isomorphic DHR categories. We show some geometric properties of the "duality pairing" between local algebras and the DHR category that are valid in general (completely rational) chiral CFTs. Under some additional assumptions whose status remains to be settled, the braided action of its DHR category completely classifies a (prime) CFT. The approach does not refer to the vacuum representation, or the knowledge of the vacuum state.

Power optimization in logic isomers

NASA Technical Reports Server (NTRS)

Panwar, Ramesh; Rennels, David; Alkalaj, Leon

1993-01-01

Logic isomers are labeled, 2-isomorphic graphs that implement the same logic function. Logic isomers may have significantly different power requirements even though they have the same number of transistors in the implementation. The power requirements of the isomers depend on the transition activity of the input signals. The power requirements of isomorphic graph isomers of n-input NAND and NOR gates are shown. Choosing the less power-consuming isomer instead of the others can yield significant power savings. Experimental results on a ripple-carry adder are presented to show that the implementation using the least power-consuming isomers requires approximately 10 percent less power than the implementation using the most power-consuming isomers. Simulations of other random logic designs also confirm that designs using less power-consuming isomers can reduce the logic power demand by approximately 10 percent as compared to designs using more power-consuming isomers.

``Dual Society Ever Precedes through Trevor SWAN & Wassily Leontief''

NASA Astrophysics Data System (ADS)

Maksoed, Wh-

``Dual Society'' introduced by E.F. Schumacher are classified as non-stabile society who easy to shakes by politics uncertainties.in Robert J. Barro & X. Sala-i-Martin: ``Convergence''states: `` a key economic issue is whether poor countries or regions tend to grow faster than rich ones''.For growth models from Roy Forbes Herrod & EvseyDomar, three assumptions described by Eduardo Ley are?[U+2639]i). output is proportional to capital,(ii). Investment ex anteequals saving & (iii) saving proportional to output. Underlines Trevor SWAN, developing countries differ significantly among themselves. Economic growth models comprises Herrod-Domar growth model, Solow growth model & endogenous growth model.Further, for five stages of economic groeth from Rostov of Leontief technology, ever retrieves the Jens Beckert:''Institutional Isomorphism revisited: Convergence & Divergence in Institutional Change''instead Frumkin's ``Institutional Isomorphism & Public Sector Organizations''. Acknowledgment devotes to theLates HE. Mr. BrigadierGeneral-TNI[rtd].Prof. Ir. HANDOJO.

Replicator equations, maximal cliques, and graph isomorphism.

PubMed

Pelillo, M

1999-11-15

We present a new energy-minimization framework for the graph isomorphism problem that is based on an equivalent maximum clique formulation. The approach is centered around a fundamental result proved by Motzkin and Straus in the mid-1960s, and recently expanded in various ways, which allows us to formulate the maximum clique problem in terms of a standard quadratic program. The attractive feature of this formulation is that a clear one-to-one correspondence exists between the solutions of the quadratic program and those in the original, combinatorial problem. To solve the program we use the so-called replicator equations--a class of straightforward continuous- and discrete-time dynamical systems developed in various branches of theoretical biology. We show how, despite their inherent inability to escape from local solutions, they nevertheless provide experimental results that are competitive with those obtained using more elaborate mean-field annealing heuristics.

Corrigendum to: "Crystal growth and magnetic characterization of a tetragonal polymorph of NiNb2O6" [J. Solid State Chem. 236 (2016) 19-23

NASA Astrophysics Data System (ADS)

Munsie, T. J. S.; Millington, A.; Dube, P. A.; Dabkowska, H. A.; Britten, J.; Luke, G. M.; Greedan, J. E.

2016-07-01

We have become aware of an error in this published manuscript. In it we stated that the space group of NiNb2O6, P42/n, is not a subgroup of the tri-rutile space group, P42/mnm. This is not correct. While the two space groups are not directly related, i.e. by a single step, they are connected via the intermediate symmetry P42/m, as shown below and which can be determined from a careful perusal of the International Tables for Crystallography (Vol. A) and of course the Bilbao Server. P42/m (#86) is a maximal non-isomorphic subgroup of P42/mnm (#186) and a minimal non-isomorphic supergroup of P42/n (#84). We thank Prof. J.M. Perez-Mato for guiding our understanding of these relationships.

Neuromorphic photonic networks using silicon photonic weight banks.

PubMed

Tait, Alexander N; de Lima, Thomas Ferreira; Zhou, Ellen; Wu, Allie X; Nahmias, Mitchell A; Shastri, Bhavin J; Prucnal, Paul R

2017-08-07

Photonic systems for high-performance information processing have attracted renewed interest. Neuromorphic silicon photonics has the potential to integrate processing functions that vastly exceed the capabilities of electronics. We report first observations of a recurrent silicon photonic neural network, in which connections are configured by microring weight banks. A mathematical isomorphism between the silicon photonic circuit and a continuous neural network model is demonstrated through dynamical bifurcation analysis. Exploiting this isomorphism, a simulated 24-node silicon photonic neural network is programmed using "neural compiler" to solve a differential system emulation task. A 294-fold acceleration against a conventional benchmark is predicted. We also propose and derive power consumption analysis for modulator-class neurons that, as opposed to laser-class neurons, are compatible with silicon photonic platforms. At increased scale, Neuromorphic silicon photonics could access new regimes of ultrafast information processing for radio, control, and scientific computing.

The BRST complex of homological Poisson reduction

NASA Astrophysics Data System (ADS)

Müller-Lennert, Martin

2017-02-01

BRST complexes are differential graded Poisson algebras. They are associated with a coisotropic ideal J of a Poisson algebra P and provide a description of the Poisson algebra (P/J)^J as their cohomology in degree zero. Using the notion of stable equivalence introduced in Felder and Kazhdan (Contemporary Mathematics 610, Perspectives in representation theory, 2014), we prove that any two BRST complexes associated with the same coisotropic ideal are quasi-isomorphic in the case P = R[V] where V is a finite-dimensional symplectic vector space and the bracket on P is induced by the symplectic structure on V. As a corollary, the cohomology of the BRST complexes is canonically associated with the coisotropic ideal J in the symplectic case. We do not require any regularity assumptions on the constraints generating the ideal J. We finally quantize the BRST complex rigorously in the presence of infinitely many ghost variables and discuss the uniqueness of the quantization procedure.

Gain-Sparsity and Symmetry-Forced Rigidity in the Plane.

PubMed

Jordán, Tibor; Kaszanitzky, Viktória E; Tanigawa, Shin-Ichi

We consider planar bar-and-joint frameworks with discrete point group symmetry in which the joint positions are as generic as possible subject to the symmetry constraint. We provide combinatorial characterizations for symmetry-forced rigidity of such structures with rotation symmetry or dihedral symmetry of order 2 k with odd k , unifying and extending previous work on this subject. We also explore the matroidal background of our results and show that the matroids induced by the row independence of the orbit matrices of the symmetric frameworks are isomorphic to gain sparsity matroids defined on the quotient graph of the framework, whose edges are labeled by elements of the corresponding symmetry group. The proofs are based on new Henneberg type inductive constructions of the gain graphs that correspond to the bases of the matroids in question, which can also be seen as symmetry preserving graph operations in the original graph.

Regulation of the demographic structure in isomorphic biphasic life cycles at the spatial fine scale.

PubMed

Vieira, Vasco Manuel Nobre de Carvalho da Silva; Mateus, Marcos Duarte

2014-01-01

Isomorphic biphasic algal life cycles often occur in the environment at ploidy abundance ratios (Haploid:Diploid) different from 1. Its spatial variability occurs within populations related to intertidal height and hydrodynamic stress, possibly reflecting the niche partitioning driven by their diverging adaptation to the environment argued necessary for their prevalence (evolutionary stability). Demographic models based in matrix algebra were developed to investigate which vital rates may efficiently generate an H:D variability at a fine spatial resolution. It was also taken into account time variation and type of life strategy. Ploidy dissimilarities in fecundity rates set an H:D spatial structure miss-fitting the ploidy fitness ratio. The same happened with ploidy dissimilarities in ramet growth whenever reproductive output dominated the population demography. Only through ploidy dissimilarities in looping rates (stasis, breakage and clonal growth) did the life cycle respond to a spatially heterogeneous environment efficiently creating a niche partition. Marginal locations were more sensitive than central locations. Related results have been obtained experimentally and numerically for widely different life cycles from the plant and animal kingdoms. Spore dispersal smoothed the effects of ploidy dissimilarities in fertility and enhanced the effects of ploidy dissimilarities looping rates. Ploidy dissimilarities in spore dispersal could also create the necessary niche partition, both over the space and time dimensions, even in spatial homogeneous environments and without the need for conditional differentiation of the ramets. Fine scale spatial variability may be the key for the prevalence of isomorphic biphasic life cycles, which has been neglected so far.

Regulation of the Demographic Structure in Isomorphic Biphasic Life Cycles at the Spatial Fine Scale

PubMed Central

Vieira, Vasco Manuel Nobre de Carvalho da Silva; Mateus, Marcos Duarte

2014-01-01

Isomorphic biphasic algal life cycles often occur in the environment at ploidy abundance ratios (Haploid:Diploid) different from 1. Its spatial variability occurs within populations related to intertidal height and hydrodynamic stress, possibly reflecting the niche partitioning driven by their diverging adaptation to the environment argued necessary for their prevalence (evolutionary stability). Demographic models based in matrix algebra were developed to investigate which vital rates may efficiently generate an H:D variability at a fine spatial resolution. It was also taken into account time variation and type of life strategy. Ploidy dissimilarities in fecundity rates set an H:D spatial structure miss-fitting the ploidy fitness ratio. The same happened with ploidy dissimilarities in ramet growth whenever reproductive output dominated the population demography. Only through ploidy dissimilarities in looping rates (stasis, breakage and clonal growth) did the life cycle respond to a spatially heterogeneous environment efficiently creating a niche partition. Marginal locations were more sensitive than central locations. Related results have been obtained experimentally and numerically for widely different life cycles from the plant and animal kingdoms. Spore dispersal smoothed the effects of ploidy dissimilarities in fertility and enhanced the effects of ploidy dissimilarities looping rates. Ploidy dissimilarities in spore dispersal could also create the necessary niche partition, both over the space and time dimensions, even in spatial homogeneous environments and without the need for conditional differentiation of the ramets. Fine scale spatial variability may be the key for the prevalence of isomorphic biphasic life cycles, which has been neglected so far. PMID:24658603

Wheeled Pro(p)file of Batalin-Vilkovisky Formalism

NASA Astrophysics Data System (ADS)

Merkulov, S. A.

2010-05-01

Using a technique of wheeled props we establish a correspondence between the homotopy theory of unimodular Lie 1-bialgebras and the famous Batalin-Vilkovisky formalism. Solutions of the so-called quantum master equation satisfying certain boundary conditions are proven to be in 1-1 correspondence with representations of a wheeled dg prop which, on the one hand, is isomorphic to the cobar construction of the prop of unimodular Lie 1-bialgebras and, on the other hand, is quasi-isomorphic to the dg wheeled prop of unimodular Poisson structures. These results allow us to apply properadic methods for computing formulae for a homotopy transfer of a unimodular Lie 1-bialgebra structure on an arbitrary complex to the associated quantum master function on its cohomology. It is proven that in the category of quantum BV manifolds associated with the homotopy theory of unimodular Lie 1-bialgebras quasi-isomorphisms are equivalence relations. It is shown that Losev-Mnev’s BF theory for unimodular Lie algebras can be naturally extended to the case of unimodular Lie 1-bialgebras (and, eventually, to the case of unimodular Poisson structures). Using a finite-dimensional version of the Batalin-Vilkovisky quantization formalism it is rigorously proven that the Feynman integrals computing the effective action of this new BF theory describe precisely homotopy transfer formulae obtained within the wheeled properadic approach to the quantum master equation. Quantum corrections (which are present in our BF model to all orders of the Planck constant) correspond precisely to what are often called “higher Massey products” in the homological algebra.

A rational approach to heavy-atom derivative screening

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

Joyce, M. Gordon; Radaev, Sergei; Sun, Peter D., E-mail: psun@nih.gov

2010-04-01

In order to overcome the difficulties associated with the ‘classical’ heavy-atom derivatization procedure, an attempt has been made to develop a rational crystal-free heavy-atom-derivative screening method and a quick-soak derivatization procedure which allows heavy-atom compound identification. Despite the development in recent times of a range of techniques for phasing macromolecules, the conventional heavy-atom derivatization method still plays a significant role in protein structure determination. However, this method has become less popular in modern high-throughput oriented crystallography, mostly owing to its trial-and-error nature, which often results in lengthy empirical searches requiring large numbers of well diffracting crystals. In addition, the phasingmore » power of heavy-atom derivatives is often compromised by lack of isomorphism or even loss of diffraction. In order to overcome the difficulties associated with the ‘classical’ heavy-atom derivatization procedure, an attempt has been made to develop a rational crystal-free heavy-atom derivative-screening method and a quick-soak derivatization procedure which allows heavy-atom compound identification. The method includes three basic steps: (i) the selection of likely reactive compounds for a given protein and specific crystallization conditions based on pre-defined heavy-atom compound reactivity profiles, (ii) screening of the chosen heavy-atom compounds for their ability to form protein adducts using mass spectrometry and (iii) derivatization of crystals with selected heavy-metal compounds using the quick-soak method to maximize diffraction quality and minimize non-isomorphism. Overall, this system streamlines the process of heavy-atom compound identification and minimizes the problem of non-isomorphism in phasing.« less

A Taoist Paradigm of EAP Consultation.

ERIC Educational Resources Information Center

Gerstein, Lawrence H.; Sturmer, Paul

1993-01-01

Describes new Taoist model as alternative approach to conceptualizing consultation process and to formulating successful, isomorphic interventions constructed to facilitate four change processes. Presents model stressing importance of interrelationships between individuals and groups; integrating repulsion and assimilation forces; balancing human…

Parallel computing of physical maps--a comparative study in SIMD and MIMD parallelism.

PubMed

Bhandarkar, S M; Chirravuri, S; Arnold, J

1996-01-01

Ordering clones from a genomic library into physical maps of whole chromosomes presents a central computational problem in genetics. Chromosome reconstruction via clone ordering is usually isomorphic to the NP-complete Optimal Linear Arrangement problem. Parallel SIMD and MIMD algorithms for simulated annealing based on Markov chain distribution are proposed and applied to the problem of chromosome reconstruction via clone ordering. Perturbation methods and problem-specific annealing heuristics are proposed and described. The SIMD algorithms are implemented on a 2048 processor MasPar MP-2 system which is an SIMD 2-D toroidal mesh architecture whereas the MIMD algorithms are implemented on an 8 processor Intel iPSC/860 which is an MIMD hypercube architecture. A comparative analysis of the various SIMD and MIMD algorithms is presented in which the convergence, speedup, and scalability characteristics of the various algorithms are analyzed and discussed. On a fine-grained, massively parallel SIMD architecture with a low synchronization overhead such as the MasPar MP-2, a parallel simulated annealing algorithm based on multiple periodically interacting searches performs the best. For a coarse-grained MIMD architecture with high synchronization overhead such as the Intel iPSC/860, a parallel simulated annealing algorithm based on multiple independent searches yields the best results. In either case, distribution of clonal data across multiple processors is shown to exacerbate the tendency of the parallel simulated annealing algorithm to get trapped in a local optimum.

Cognitive Theory. Volume 2.

ERIC Educational Resources Information Center

Castellan, N. John, Jr., Ed.; And Others

The conference papers in this collection emphasize the theoretical significance of their authors' work in the areas of mathematical and cognitive psychology. Major topics considered include facilitation of problem solving; psychological differences among problem isomorphs; the process of understanding in problem solving; processing information for…

Expression, purification, crystallization and preliminary crystallographic study of isolated modules of the mouse coactivator-associated arginine methyltransferase 1

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

Troffer-Charlier, Nathalie; Cura, Vincent; Hassenboehler, Pierre

2007-04-01

Isolated modules of mouse coactivator-associated arginine methyltransferase 1 encompassing the protein arginine N-methyltransferase catalytic domain have been overexpressed, purified and crystallized. X-ray diffraction data have been collected and have enabled determination of the structures by multiple isomorphous replacement using anomalous scattering. Coactivator-associated arginine methyltransferase 1 (CARM1) plays a crucial role in gene expression as a coactivator of several nuclear hormone receptors and also of non-nuclear receptor systems. Its recruitment by the transcriptional machinery induces protein methylation, leading to chromatin remodelling and gene activation. CARM1{sub 28–507} and two structural states of CARM1{sub 140–480} were expressed, purified and crystallized. Crystals of CARM1{submore » 28–507} belong to space group P6{sub 2}22, with unit-cell parameters a = b = 136.0, c = 125.3 Å; they diffract to beyond 2.5 Å resolution using synchrotron radiation and contain one monomer in the asymmetric unit. The structure of CARM1{sub 28–507} was solved by multiple isomorphous replacement and anomalous scattering methods. Crystals of apo CARM1{sub 140–480} belong to space group I222, with unit-cell parameters a = 74.6, b = 99.0, c = 207.4 Å; they diffract to beyond 2.7 Å resolution and contain two monomers in the asymmetric unit. Crystals of CARM1{sub 140–480} in complex with S-adenosyl-l-homocysteine belong to space P2{sub 1}2{sub 1}2, with unit-cell parameters a = 74.6, b = 98.65, c = 206.08 Å; they diffract to beyond 2.6 Å resolution and contain four monomers in the asymmetric unit. The structures of apo and holo CARM1{sub 140–480} were solved by molecular-replacement techniques from the structure of CARM1{sub 28–507}.« less

Direct detection of the optical field beyond single polarization mode.

PubMed

Che, Di; Sun, Chuanbowen; Shieh, William

2018-02-05

Direct detection is traditionally regarded as a detection method that recovers only the optical intensity. Compared with coherent detection, it owns a natural advantage-the simplicity-but lacks a crucial capability of field recovery that enables not only the multi-dimensional modulation, but also the digital compensation of the fiber impairments linear with the optical field. Full-field detection is crucial to increase the capacity-distance product of optical transmission systems. A variety of methods have been investigated to directly detect the optical field of the single polarization mode, which normally sends a carrier traveling with the signal for self-coherent detection. The crux, however, is that any optical transmission medium supports at least two propagating modes (e.g. single mode fiber supports two polarization modes), and until now there is no direct detection that can recover the complete set of optical fields beyond one polarization, due to the well-known carrier fading issue after mode demultiplexing induced by the random mode coupling. To avoid the fading, direct detection receivers should recover the signal in an intensity space isomorphic to the optical field without loss of any degrees of freedom, and a bridge should be built between the field and its isomorphic space for the multi-mode field recovery. Based on this thinking, we propose, for the first time, the direct detection of dual polarization modes by a novel receiver concept, the Stokes-space field receiver (SSFR) and its extension, the generalized SSFR for multiple spatial modes. The idea is verified by a dual-polarization field recovery of a polarization-multiplexed complex signal over an 80-km single mode fiber transmission. SSFR can be applied to a much wider range of fields beyond optical communications such as coherent sensing and imaging, where simple field recovery without an extra local laser is desired for enhanced system performance.

Response to K. Anderson-Levitt's Rejoinder.

ERIC Educational Resources Information Center

LeTendre, Gerald; Baker, David; Akiba, Motoko; Goesling, Brian; Wiseman, Alex

2002-01-01

Responds to a commentary on "Teachers' Work: Institutional Isomorphism and Cultural Variation in the U.S., Germany and Japan," suggesting that the article raises several useful issues about global versus national cultures, institutionalization, and comparative analysis of teaching in three nations. Clarifies argument and illustrates…

Managing Mergers--Governancing Institutional Integration

ERIC Educational Resources Information Center

Frølich, Nicoline; Trondal, Jarle; Caspersen, Joakim; Reymert, Ingvild

2016-01-01

Despite striking similarities, the adoption and implementation of policy shifts regarding higher education governance vary considerably across the globe, suggesting a mixed picture of diversification and isomorphism both within and across national higher education systems. By unpacking one particular structural reform process, this paper focuses…

The Ulam Index: Methods of Theoretical Computer Science Help in Identifying Chemical Substances

NASA Technical Reports Server (NTRS)

Beltran, Adriana; Salvador, James

1997-01-01

In this paper, we show how methods developed for solving a theoretical computer problem of graph isomorphism are used in structural chemistry. We also discuss potential applications of these methods to exobiology: the search for life outside Earth.

Structural Changes Correlated with Magnetic Spin State Isomorphism in the S2 State of the Mn4CaO5 Cluster in the Oxygen-Evolving Complex of Photosystem II

PubMed Central

Chatterjee, Ruchira; Han, Guangye; Kern, Jan; Gul, Sheraz; Fuller, Franklin D.; Garachtchenko, Anna; Young, Iris; Weng, Tsu-Chien; Nordlund, Dennis; Alonso-Mori, Roberto; Bergmann, Uwe; Sokaras, Dimosthenis; Hatakeyama, Makoto; Yachandra, Vittal K.; Yano, Junko

2016-01-01

The Mn4CaO5 cluster in Photosystem II catalyzes the four-electron redox reaction of water oxidation in natural photosynthesis. This catalytic reaction cycles through four intermediate states (Si, i = 0 to 4), involving changes in the redox state of the four Mn atoms in the cluster. Recent studies suggest the presence and importance of isomorphous structures within the same redox/intermediate S-state. It is highly likely that geometric and electronic structural flexibility play a role in the catalytic mechanism. Among the catalytic intermediates that have been identified experimentally thus far, there is clear evidence of such isomorphism in the S2 state, with a high-spin (5/2) (HS) and a low spin (1/2) (LS) form, identified and characterized by their distinct electron paramagnetic resonance (EPR spectroscopy) signals. We studied these two S2 isomers with Mn extended X-ray absorption fine structure (EXAFS) and absorption and emission spectroscopy (XANES/XES) to characterize the structural and electronic structural properties. The geometric and electronic structure of the HS and LS S2 states are different as determined using Mn EXAFS and XANES/XES, respectively. The Mn K-edge XANES and XES for the HS form are different from the LS and indicate a slightly lower positive charge on the Mn atoms compared to the LS form. Based on the EXAFS results which are clearly different, we propose possible structural differences between the two spin states. Such structural and magnetic redox-isomers if present at room temperature, will likely play a role in the mechanism for water-exchange/oxidation in photosynthesis. PMID:28044099

Immobilization of actinides in stable mineral type and ceramic materials (high temperature synthesis)

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

Starkov, O.; Konovalov, E.

1996-05-01

Alternative vitrification technologies are being developed in the world for the immobilization of high radioactive waste in materials with improved thermodynamic stability, as well as improved chemical and thermal stability and stability to radiation. Oxides, synthesized in the form of analogs to rock-forming minerals and ceramics, are among those materials that have highly stable properties and are compatible with the environment. In choosing the appropriate material, we need to be guided by its geometric stability, the minimal number of cations in the structure of the material and the presence of structural elements in the mineral that are isomorphs of uraniummore » and thorium, actinoids found in nature. Rare earth elements, yttrium, zirconium and calcium are therefore suitable. The minerals listed in the table (with the exception of the zircon) are pegatites by origin, i.e. they are formed towards the end of the magma crystallization of silicates form the residual melt, enriched with Ta, Nb, Ti, Zr, Ce, Y, U and Th. Uranium and thorium in the form of isomorphic admixtures form part of the lattice of the mineral. These minerals, which are rather simple in composition and structure and are formed under high temperatures, may be viewed as natural physio-chemical systems that are stable and long-lived in natural environments. The similarity of the properties of actinoids and lanthanoids plays an important role in the geochemistry of uranium and thorium; however, uranium (IV) is closer to the {open_quotes}heavy{close_quotes} group of lanthanoids (the yttrium group) while thorium (IV) is closer to the {open_quotes}light{close_quotes} group (the cerium group). That is why rare earth minerals contain uranium and thorium in the form of isomorphic admixtures.« less

Structural changes correlated with magnetic spin state isomorphism in the S 2 state of the Mn 4CaO 5 cluster in the oxygen-evolving complex of photosystem II

DOE PAGES

Chatterjee, Ruchira; Han, Guangye; Kern, Jan; ...

2016-05-09

The Mn 4CaO 5 cluster in photosystem II catalyzes the four-electron redox reaction of water oxidation in natural photosynthesis. This catalytic reaction cycles through four intermediate states (S i, i = 0 to 4), involving changes in the redox state of the four Mn atoms in the cluster. Recent studies suggest the presence and importance of isomorphous structures within the same redox/intermediate S-state. It is highly likely that geometric and electronic structural flexibility play a role in the catalytic mechanism. Among the catalytic intermediates that have been identified experimentally thus far, there is clear evidence of such isomorphism in themore » S2 state, with a high-spin (5/2) (HS) and a low spin (1/2) (LS) form, identified and characterized by their distinct electron paramagnetic resonance (EPR spectroscopy) signals. We studied these two S2 isomers with Mn extended X-ray absorption fine structure (EXAFS) and absorption and emission spectroscopy (XANES/XES) to characterize the structural and electronic structural properties. The geometric and electronic structure of the HS and LS S2 states are different as determined using Mn EXAFS and XANES/XES, respectively. The Mn K-edge XANES and XES for the HS form are different from the LS and indicate a slightly lower positive charge on the Mn atoms compared to the LS form. Based on the EXAFS results which are clearly different, we propose possible structural differences between the two spin states. As a result, such structural and magnetic redox-isomers if present at room temperature, will likely play a role in the mechanism for water-exchange/oxidation in photosynthesis.« less

The assembly of two isomorphous coordination compounds based on 1,4-cyclohexanedicarboxylic acid and 2,4-diamino-6-phenyl-1,3,5-triazine

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

Li, Xue-Fei; Wang, Xiao; Lun, Hui-Jie

The compounds [Co(e,a-cis-1,4-chdc)(phdat)]{sub n} (1) and [Cd(e,a-cis-1,4-chdc)(phdat)]{sub n} (2) have been synthesized under hydrothermal method by using 1,4-cyclohexanedicarboxylic acid (1,4-H{sub 2}chdc), 2,4-diamino-6-phenyl-1,3,5-triazine (phdat) as well as CoCl{sub 2}·6H{sub 2}O, CdCl{sub 2}·2.5H{sub 2}O respectively and characterized by IR spectra, X-ray single-crystal diffraction, powder X-ray single-crystal diffraction (PXRD), elemental analyses and thermogravimetric analyses (TGA). The results show the compounds 1 and 2 are isomorphous and exhibit paddle-wheel dinuclear Co{sub 2}(CO{sub 2}){sub 4}/Cd{sub 2}(CO{sub 2}){sub 4} units, which are further connected to 1D chain structures by μ{sub 4}:η{sup 1}:η{sup 1}:η{sup 1}:η{sup 1} 1,4-chdc{sup 2–} ligands and extended into a 3D structures via differentmore » hydrogen bonding and π…π stacking interactions. Furthermore, compound 1 exhibits antiferromagnetic behavior and compound 2 displays luminescent behavior at solid state. - Graphical abstract: Two isomorphous coordination compounds 1–2 have been synthesized and characterized by XRD, IR spectra and TGA etc. Compound 1 and 2 display antiferromagnetic behavior and luminescent behavior respectively. - Highlights: • Two novel polymers based on 1,4-cyclohexanedicarboxylic acid have been synthesized. • Compounds 1 and 2 feather 1D chain structure built up from paddle-wheel SBUs. • The magnetism of 2 is investigated. • The electrochemical property and luminescent property of 1 are investigated.« less

Highly efficient periodically poled KTP-isomorphs with large apertures and extreme domain aspect-ratios

NASA Astrophysics Data System (ADS)

Canalias, Carlota; Zukauskas, Andrius; Tjörnhamman, Staffan; Viotti, Anne-Lise; Pasiskevicius, Valdas; Laurell, Fredrik

2018-02-01

Since the early 1990's, a substantial effort has been devoted to the development of quasi-phased-matched (QPM) nonlinear devices, not only in ferroelectric oxides like LiNbO3, LiTaO3 and KTiOPO4 (KTP), but also in semiconductors as GaAs, and GaP. The technology to implement QPM structures in ferroelectric oxides has by now matured enough to satisfy the most basic frequency-conversion schemes without substantial modification of the poling procedures. Here, we present a qualitative leap in periodic poling techniques that allows us to demonstrate devices and frequency conversion schemes that were deemed unfeasible just a few years ago. Thanks to our short-pulse poling and coercive-field engineering techniques, we are able to demonstrate large aperture (5 mm) periodically poled Rb-doped KTP devices with a highly-uniform conversion efficiency over the whole aperture. These devices allow parametric conversion with energies larger than 60 mJ. Moreover, by employing our coercive-field engineering technique we fabricate highlyefficient sub-µm periodically poled devices, with periodicities as short as 500 nm, uniform over 1 mm-thick crystals, which allow us to realize mirrorless optical parametric oscillators with counter-propagating signal and idler waves. These novel devices present unique spectral and tuning properties, superior to those of conventional OPOs. Furthermore, our techniques are compatible with KTA, a KTP isomorph with extended transparency in the mid-IR range. We demonstrate that our highly-efficient PPKTA is superior both for mid-IR and for green light generation - as a result of improved transmission properties in the visible range. Our KTP-isomorph poling techniques leading to highly-efficient QPM devices will be presented. Their optical performance and attractive damage thresholds will be discussed.

Student Reasoning about Graphs in Different Contexts

ERIC Educational Resources Information Center

Ivanjek, Lana; Susac, Ana; Planinic, Maja; Andrasevic, Aneta; Milin-Sipus, Zeljka

2016-01-01

This study investigates university students' graph interpretation strategies and difficulties in mathematics, physics (kinematics), and contexts other than physics. Eight sets of parallel (isomorphic) mathematics, physics, and other context questions about graphs, which were developed by us, were administered to 385 first-year students at the…

School Leadership Policy Trends and Developments: Policy Expediency or Policy Excellence?

ERIC Educational Resources Information Center

Roach, Virginia; Smith, L. Wes; Boutin, James

2011-01-01

Background: Institutional theorists suggest environmental stakeholders in the "organizational field" have a symbiotic relationship with governing agencies, leading to institutional isomorphism. Hence state policy makers copy the work of their colleagues across states to create a sense of legitimacy, certainty, and professionalization…

Neural coding strategies in auditory cortex.

PubMed

Wang, Xiaoqin

2007-07-01

In contrast to the visual system, the auditory system has longer subcortical pathways and more spiking synapses between the peripheral receptors and the cortex. This unique organization reflects the needs of the auditory system to extract behaviorally relevant information from a complex acoustic environment using strategies different from those used by other sensory systems. The neural representations of acoustic information in auditory cortex can be characterized by three types: (1) isomorphic (faithful) representations of acoustic structures; (2) non-isomorphic transformations of acoustic features and (3) transformations from acoustical to perceptual dimensions. The challenge facing auditory neurophysiologists is to understand the nature of the latter two transformations. In this article, I will review recent studies from our laboratory regarding temporal discharge patterns in auditory cortex of awake marmosets and cortical representations of time-varying signals. Findings from these studies show that (1) firing patterns of neurons in auditory cortex are dependent on stimulus optimality and context and (2) the auditory cortex forms internal representations of sounds that are no longer faithful replicas of their acoustic structures.

Pair Potential That Reproduces the Shape of Isochrones in Molecular Liquids.

PubMed

Veldhorst, Arno A; Schrøder, Thomas B; Dyre, Jeppe C

2016-08-18

Many liquids have curves (isomorphs) in their phase diagrams along which structure, dynamics, and some thermodynamic quantities are invariant in reduced units. A substantial part of their phase diagrams is thus effectively one dimensional. The shapes of these isomorphs are described by a material-dependent function of density, h(ρ), which for real liquids is well approximated by a power law, ρ(γ). However, in simulations, a power law is not adequate when density changes are large; typical models, such as Lennard-Jones liquids, show that γ(ρ) ≡ d ln h(ρ)/d ln ρ is a decreasing function of density. This article presents results from computer simulations using a new pair potential that diverges at a nonzero distance and can be tuned to give a more realistic shape of γ(ρ). Our results indicate that the finite size of molecules is an important factor to take into account when modeling liquids over a large density range.

Cosegregation of Robertsonian metacentric chromosomes in the first meiotic division of multiple heterozygous male mice as revealed by FISH analysis of spermatocyte II metaphases.

PubMed

Scascitelli, M; Pacchierotti, F; Rizzoni, M; Gustavino, B; Spirito, F

2003-01-01

Contrasting results (random segregation or cosegregation of isomorphic chromosomes) have been reported up to now on the segregation pattern of Robertsonian metacentric chromosomes of Mus musculus domesticus in multiple heterozygotes, using different approaches (karyotypical analysis of the progeny or of second meiotic metaphases). In the present contribution data are presented based on FISH (Fluorescence In Situ Hybridisation) analysis with telomeric probes, which allowed us to distinguish metacentric chromosomes from pairs of acrocentric chromosomes with their centromeric regions close to each other. Probes were hybridized to DAPI stained metaphases of spermatocytes II of mice heterozygous for two, three or four Robertsonian metacentrics in an all-acrocentric background, the karyotype of which has been reconstructed starting from laboratory strains. Isomorphic chromosomes tend to cosegregate (metacentrics with metacentrics, acrocentrics with acrocentrics); the values found for cosegregation have a clear even if moderate effect on the reproductive isolation caused by underdominant chromosomal rearrangements. Copyright 2003 S. Karger AG, Basel

Melting relations and elemental distribution of portion of the system Fe-S-Si-O to 32 KB with planetary application

NASA Technical Reports Server (NTRS)

Huang, W. L.

1980-01-01

The melting relations and distribution of K and Cs in portions of the system was determined at high pressures. Ferrosilite is stable as a primary phase at high pressures because of the incongruent melting of ferrosilite to quartz plus liquid and the boundary between the one and two liquid fields on the joint Fe(1-x) O-FeS-SiO2 shifts away from silica with increasing pressures. Potassium K was found to have limited solubility in metal sulfide liquids at pressures up to 45 kb. The speculation that K may dissolve significantly in metal-metal sulfide liquids after undergoing first order isomorphic transition was tested by determining the distribution of Cs between sulfide and silicate liquids as an analogy to K. At 45 kb, 1400 C and 27 kb, 1300 C only limited amounts of Cs were detected in quench sulfide liquids even at pressures beyond the isomorphic transition of Cs.

Adsorption mechanisms of the nonequilibrium incorporation of admixtures in a growing crystal

NASA Astrophysics Data System (ADS)

Franke, V. D.; Punin, Yu. O.; Smetannikova, O. G.; Kenunen, D. S.

2007-12-01

The nonequilibrium partition of components between a crystal and solution is mainly controlled by impurity adsorption on the surface of the growing crystal. The specificity of adsorption on the faces of various simple forms leads to the sectorial zoning of crystals. This effect was studied experimentally for several crystallizing systems with different impurities, including isomorphous, 2d-isomorphous, and nonisomorphous, readily adsorbed impurities. In all systems, the sectorial selectivity of impurity incorporation into host crystals has been detected with partition coefficients many times higher than in the case of equilibrium partition. Specific capture of impurities by certain faces is accompanied by inhibition of their growth and modification of habit. The decrease in nonequilibrium partition coefficients with degree of oversaturation provides entrapment of impurities in the growing crystals. Thereby, the adsorption mechanism works in much the same mode for impurities of quite different nature. The behavior of partition coefficient differs drastically from impurity capturing by diffusion mechanism.

Institutionalization of Higher Vocational Education in China: A Neoinstitutionalist Perspective

ERIC Educational Resources Information Center

Xiong, Jie

2013-01-01

From the perspective of neoinstitutionalism, higher vocational education has become an emerging institution in Chinese society. Its development over three decades entails a trend of institutionalization of higher vocational education. In such a process, higher vocational education is gaining legitimacy and experiencing isomorphic changes. Various…

The Modern Origin of Matrices and Their Applications

ERIC Educational Resources Information Center

Debnath, L.

2014-01-01

This paper deals with the modern development of matrices, linear transformations, quadratic forms and their applications to geometry and mechanics, eigenvalues, eigenvectors and characteristic equations with applications. Included are the representations of real and complex numbers, and quaternions by matrices, and isomorphism in order to show…

Use Your Imagination: What UK Universities Want You to Think of Them

ERIC Educational Resources Information Center

Huisman, Jeroen; Mampaey, Jelle

2018-01-01

In higher education research, theoretical approaches stressing isomorphism dominate the discourse on how higher education institutions 'behave' in their higher education and research systems. We argue that research should address both instances of similarity and differences. Using theoretical notions from institutionalism and the…

The University as Microcosm

ERIC Educational Resources Information Center

Kaldis, Byron

2009-01-01

This paper puts forward the model of "microcosm-macrocosm" isomorphism encapsulated in certain philosophical views on the form of university education. The human being as a "microcosm" should reflect internally the external "macrocosm". Higher Education is a socially instituted attempt to guide human beings into forming themselves as microcosms of…

The Nature of the Microstructure and Interface Boundary Formation in Directionally Solidified Ceramic Boride Composites

DTIC Science & Technology

2011-05-01

failure resistance, which results from their different microplasticity (microbrittleness) and relaxation ability. In order to evaluate the... microplasticity (microbrittleness) in the series of isomorphic hexaborides produced by zone melting we have plotted a number of statistical curves that show

Intercultural Education and the Crisis of Globalisation: Some Reflections

ERIC Educational Resources Information Center

Coulby, David

2011-01-01

In this essay I reflect on the role of intercultural education in an emerging global crisis. Education systems are characterised by both divergent and convergent impulses. Divergent impulses include tradition, nationalism and religion. Convergent impulses (isomorphism) include science and technology, culture (including the English language),…

Integrability and nonintegrability of quantum systems. II. Dynamics in quantum phase space

NASA Astrophysics Data System (ADS)

Zhang, Wei-Min; Feng, Da Hsuan; Yuan, Jian-Min

1990-12-01

Based on the concepts of integrability and nonintegrability of a quantum system presented in a previous paper [Zhang, Feng, Yuan, and Wang, Phys. Rev. A 40, 438 (1989)], a realization of the dynamics in the quantum phase space is now presented. For a quantum system with dynamical group scrG and in one of its unitary irreducible-representation carrier spaces gerhΛ, the quantum phase space is a 2MΛ-dimensional topological space, where MΛ is the quantum-dynamical degrees of freedom. This quantum phase space is isomorphic to a coset space scrG/scrH via the unitary exponential mapping of the elementary excitation operator subspace of scrg (algebra of scrG), where scrH (⊂scrG) is the maximal stability subgroup of a fixed state in gerhΛ. The phase-space representation of the system is realized on scrG/scrH, and its classical analogy can be obtained naturally. It is also shown that there is consistency between quantum and classical integrability. Finally, a general algorithm for seeking the manifestation of ``quantum chaos'' via the classical analogy is provided. Illustrations of this formulation in several important quantum systems are presented.

Language learners privilege structured meaning over surface frequency

PubMed Central

Culbertson, Jennifer; Adger, David

2014-01-01

Although it is widely agreed that learning the syntax of natural languages involves acquiring structure-dependent rules, recent work on acquisition has nevertheless attempted to characterize the outcome of learning primarily in terms of statistical generalizations about surface distributional information. In this paper we investigate whether surface statistical knowledge or structural knowledge of English is used to infer properties of a novel language under conditions of impoverished input. We expose learners to artificial-language patterns that are equally consistent with two possible underlying grammars—one more similar to English in terms of the linear ordering of words, the other more similar on abstract structural grounds. We show that learners’ grammatical inferences overwhelmingly favor structural similarity over preservation of superficial order. Importantly, the relevant shared structure can be characterized in terms of a universal preference for isomorphism in the mapping from meanings to utterances. Whereas previous empirical support for this universal has been based entirely on data from cross-linguistic language samples, our results suggest it may reflect a deep property of the human cognitive system—a property that, together with other structure-sensitive principles, constrains the acquisition of linguistic knowledge. PMID:24706789

Light sheet theta microscopy for rapid high-resolution imaging of large biological samples.

PubMed

Migliori, Bianca; Datta, Malika S; Dupre, Christophe; Apak, Mehmet C; Asano, Shoh; Gao, Ruixuan; Boyden, Edward S; Hermanson, Ola; Yuste, Rafael; Tomer, Raju

2018-05-29

Advances in tissue clearing and molecular labeling methods are enabling unprecedented optical access to large intact biological systems. These developments fuel the need for high-speed microscopy approaches to image large samples quantitatively and at high resolution. While light sheet microscopy (LSM), with its high planar imaging speed and low photo-bleaching, can be effective, scaling up to larger imaging volumes has been hindered by the use of orthogonal light sheet illumination. To address this fundamental limitation, we have developed light sheet theta microscopy (LSTM), which uniformly illuminates samples from the same side as the detection objective, thereby eliminating limits on lateral dimensions without sacrificing the imaging resolution, depth, and speed. We present a detailed characterization of LSTM, and demonstrate its complementary advantages over LSM for rapid high-resolution quantitative imaging of large intact samples with high uniform quality. The reported LSTM approach is a significant step for the rapid high-resolution quantitative mapping of the structure and function of very large biological systems, such as a clarified thick coronal slab of human brain and uniformly expanded tissues, and also for rapid volumetric calcium imaging of highly motile animals, such as Hydra, undergoing non-isomorphic body shape changes.

Preliminary neutron crystallographic analysis of selectively CH3-protonated, deuterated rubredoxin from Pyrococcus furiosus

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

Weiss, Kevin L; Meilleur, Flora; Blakeley, Matthew

2008-01-01

Neutron crystallography is used to locate hydrogen atoms in biological materials and can distinguish between negatively scattering hydrogen and positively scattering deuterium substituted positions in isomorphous neutron structures. Recently, Hauptman and Langs (2003) have shown that neutron diffraction data can be used to solve macromolecular structures by direct methods and that solution is aided by the presence of negatively scattering hydrogen atoms in the structure. Selective labeling protocols allow the design and production of H/D-labeled macromolecular structures in which the ratio of hydrogen to deuterium atoms can be precisely controlled. We have applied methyl-selective labeling protocols to introduce (1H-delta methyl)-leucinemore » and (1H-gamma methyl)-valine into deuterated rubredoxin from Pyrococcus furiosus (PfRd). Here we report on the production, crystallization, and preliminary neutron analysis of the selectively CH3-protonated, deuterated PfRd sample, which provided a high quality neutron data set extending to 1.75 resolution at the new LADI-III instrument at the Insititut Laue-Langevin. Preliminary analysis of neutron density maps allows unambiguous assignment of the positions of hydrogen atoms at the methyl groups of the valine and leucine residues in the otherwise deuterated rubredoxin structure.« less

Streaming data analytics via message passing with application to graph algorithms

DOE PAGES

Plimpton, Steven J.; Shead, Tim

2014-05-06

The need to process streaming data, which arrives continuously at high-volume in real-time, arises in a variety of contexts including data produced by experiments, collections of environmental or network sensors, and running simulations. Streaming data can also be formulated as queries or transactions which operate on a large dynamic data store, e.g. a distributed database. We describe a lightweight, portable framework named PHISH which enables a set of independent processes to compute on a stream of data in a distributed-memory parallel manner. Datums are routed between processes in patterns defined by the application. PHISH can run on top of eithermore » message-passing via MPI or sockets via ZMQ. The former means streaming computations can be run on any parallel machine which supports MPI; the latter allows them to run on a heterogeneous, geographically dispersed network of machines. We illustrate how PHISH can support streaming MapReduce operations, and describe streaming versions of three algorithms for large, sparse graph analytics: triangle enumeration, subgraph isomorphism matching, and connected component finding. Lastly, we also provide benchmark timings for MPI versus socket performance of several kernel operations useful in streaming algorithms.« less

Teaching Culture as National and Transnational: A Response to "Teachers' Work."

ERIC Educational Resources Information Center

Anderson-Levitt, Kathryn M.

2002-01-01

Comments on "Teachers' Work: Institutional Isomorphism and Cultural Variation in the U.S., Germany and Japan" (LeTendre, Baker, Akiba, Goesling, and Wiseman, 2001), applauding the blend of global culture and national culture perspectives, proposing a more systematic synthesis, discussing what it means to take both transnational parallels…

Preparation, Characterization, and Selectivity Study of Mixed-Valence Sulfites

ERIC Educational Resources Information Center

Silva, Luciana A.; de Andrade, Jailson B.

2010-01-01

A project involving the synthesis of an isomorphic double sulfite series and characterization by classical inorganic chemical analyses is described. The project is performed by upper-level undergraduate students in the laboratory. This compound series is suitable for examining several chemical concepts and analytical techniques in inorganic…

Distinctive Resources and Systemic Diversity: The Role of Signature Events in Higher Education

ERIC Educational Resources Information Center

Freed, Gwendolyn H.

2012-01-01

Systemic diversity, historically a driver of U.S. preeminence in higher education, has decreased over the past four decades (Morphew, 2009). Isomorphism in the field results from rising environmental pressures-such as for legitimacy, efficiency, comportment with industry standards, legal compliance, and accountability--amid conditions of…

Harmonic oscillator states in aberration optics

NASA Technical Reports Server (NTRS)

Wolf, Kurt Bernardo

1993-01-01

The states of the three-dimensional quantum harmonic oscillator classify optical aberrations of axis-symmetric systems due to the isomorphism between the two mathematical structures. Cartesian quanta and angular momentum classifications have their corresponding aberration classifications. The operation of concatenation of optical elements introduces a new operation between harmonic oscillator states.

Using Institutional Theory To Reframe Research on Academic Drift.

ERIC Educational Resources Information Center

Morphew, Christopher C.; Huisman, Jeroen

2002-01-01

Examines patterns of academic drift (a drift toward the structure and norms typical of more prestigious universities) in multiple higher education systems and tests the concept of "isomorphism in organizational fields" as discussed in institutional theory. Argues that the theoretical framework provided by institutional theory presents a useful…

Investigating Psychometric Isomorphism for Traditional and Performance-Based Assessment

ERIC Educational Resources Information Center

Fay, Derek M.; Levy, Roy; Mehta, Vandhana

2018-01-01

A common practice in educational assessment is to construct multiple forms of an assessment that consists of tasks with similar psychometric properties. This study utilizes a Bayesian multilevel item response model and descriptive graphical representations to evaluate the psychometric similarity of variations of the same task. These approaches for…

The Seventh Generation in Adventure Therapy.

ERIC Educational Resources Information Center

Itin, Christian

Hypnotic language provides a powerful tool for the transfer of learning in adventure therapy. It allows the therapeutic adventure practitioner to use the client's experiential language to enhance the isomorphic connections of the adventure activity and to draw upon and develop the client's unconscious resources to support client goals. This paper…

Two Patterns of Race Relations.

ERIC Educational Resources Information Center

Bonilla, Eduardo Seda

What North Americans term "race" is not structurally isomorphic to and, thus, not synonymous with what Latin Americans apply the term to. The social identities determined by "race", and consequently the expected behavior ascribed to these identities, are so dissimilar that meetings between persons of both cultures produce uncertainty and discord.…

Information-System Structure by Communication-Technology Concepts: A Cybernetic Model Approach.

ERIC Educational Resources Information Center

Reisig, Gerhard H. R.

1978-01-01

Presents the "Evidence-of-Existence" information system in which the structure is developed, with application of cybernetic concepts, as an isomorphic model in analogy to the system structure of communication technology. Three criteria of structuring are postulated: (1) source-channel-sink, with input-output characteristics, (2) filter-type…

Determinants of Successful Internationalisation Processes in Business Schools

ERIC Educational Resources Information Center

Bradford, Henry; Guzmán, Alexander; Trujillo, María-Andrea

2017-01-01

We analyse the internationalisation process in business schools as a response to the globalisation phenomena and argue that environmental pressures, isomorphic forces, the pool of internal resources and the alignment of the process with the institution's general strategic plan are the main determinants of a successful internationalisation process.…

Topological magnon bands and unconventional thermal Hall effect on the frustrated honeycomb and bilayer triangular lattice.

PubMed

Owerre, S A

2017-09-27

In the conventional ferromagnetic systems, topological magnon bands and thermal Hall effect are due to the Dzyaloshinskii-Moriya interaction (DMI). In principle, however, the DMI is either negligible or it is not allowed by symmetry in some quantum magnets. Therefore, we expect that topological magnon features will not be present in those systems. In addition, quantum magnets on the triangular-lattice are not expected to possess topological features as the DMI or spin-chirality cancels out due to equal and opposite contributions from adjacent triangles. Here, however, we predict that the isomorphic frustrated honeycomb-lattice and bilayer triangular-lattice antiferromagnetic system will exhibit topological magnon bands and topological thermal Hall effect in the absence of an intrinsic DMI. These unconventional topological magnon features are present as a result of magnetic-field-induced non-coplanar spin configurations with nonzero scalar spin chirality. The relevance of the results to realistic bilayer triangular antiferromagnetic materials are discussed.

The 2.3 {angstrom} crystal structure of cholera toxin B subunit pentamer: Choleragenoid

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

Zhang, Rong-Guang; Westbrook, M.L.; Maulik, P.R.

1996-02-01

Cholera toxin, a heterohexameric AB{sub 5} enterotoxin released by Vibrio cholera, induces a profuse secretory diarrhea in susceptible hosts. Choleragenoid, the B subunit pentamer of cholera toxin, directs the enzymatic A subunit to its target by binding to GM{sub 1} gangliosides exposed on the luminal surface of intestinal epithelial cells. We have solved the crystal structure of choleragenoid at 2.3 {Angstrom} resolution by combining single isomorphous replacement with non-crystallographic symmetry averaging. The structure of the B subunits, and their pentameric arrangement, closely resembles that reported for the intact holotoxin (choleragen), the heat-labile enterotoxin from E. coli, and for a choleragenoid-GM{submore » 1} pentasaccharide complex. In the absence of the A subunit the central cavity of the B pentamer is a highly solvated channel. The binding of the A subunit or the receptor pentasaccharide to choleragenoid has only a modest effect on the local stereochemistry and does not perceptibly alter the subunit interface.« less

Reduced multiple empirical kernel learning machine.

PubMed

Wang, Zhe; Lu, MingZhe; Gao, Daqi

2015-02-01

Multiple kernel learning (MKL) is demonstrated to be flexible and effective in depicting heterogeneous data sources since MKL can introduce multiple kernels rather than a single fixed kernel into applications. However, MKL would get a high time and space complexity in contrast to single kernel learning, which is not expected in real-world applications. Meanwhile, it is known that the kernel mapping ways of MKL generally have two forms including implicit kernel mapping and empirical kernel mapping (EKM), where the latter is less attracted. In this paper, we focus on the MKL with the EKM, and propose a reduced multiple empirical kernel learning machine named RMEKLM for short. To the best of our knowledge, it is the first to reduce both time and space complexity of the MKL with EKM. Different from the existing MKL, the proposed RMEKLM adopts the Gauss Elimination technique to extract a set of feature vectors, which is validated that doing so does not lose much information of the original feature space. Then RMEKLM adopts the extracted feature vectors to span a reduced orthonormal subspace of the feature space, which is visualized in terms of the geometry structure. It can be demonstrated that the spanned subspace is isomorphic to the original feature space, which means that the dot product of two vectors in the original feature space is equal to that of the two corresponding vectors in the generated orthonormal subspace. More importantly, the proposed RMEKLM brings a simpler computation and meanwhile needs a less storage space, especially in the processing of testing. Finally, the experimental results show that RMEKLM owns a much efficient and effective performance in terms of both complexity and classification. The contributions of this paper can be given as follows: (1) by mapping the input space into an orthonormal subspace, the geometry of the generated subspace is visualized; (2) this paper first reduces both the time and space complexity of the EKM-based MKL; (3) this paper adopts the Gauss Elimination, one of the on-the-shelf techniques, to generate a basis of the original feature space, which is stable and efficient.

N-acetylcysteine attenuates TNF-α-induced p38 MAP kinase activation and p38 MAP kinase-mediated IL-8 production by human pulmonary vascular endothelial cells

PubMed Central

Hashimoto, Shu; Gon, Yasuhiro; Matsumoto, Ken; Takeshita, Ikuko; Horie, Takashi

2001-01-01

We have previously shown that tumour necrosis factor-α (TNF-α) activates p38 mitogen-activated protein (MAP) kinase to produce interleukin-8 (IL-8) by human pulmonary vascular endothelial cells. Reactive oxygen species (ROS) including H2O2 generated by TNF-α can act as signalling intermediates for cytokine induction; therefore, scavenging ROS by anti-oxidants is important for the regulation of cytokine production. However, the effect of N-acetylcysteine (NAC), which acts as a precursor of glutathione (GSH) synthesis, on TNF-α-induced activation of p38 MAP kinase pathway and p38 MAP kinase-mediated IL-8 production by human pulmonary vascular endothelial cells has not been determined. To clarify these issues, we examined the effect of NAC on TNF-α-induced activation of p38 MAP kinase, MAP kinase kinase (MKK) 3 and MKK6 which are upstream regulators of p38 MAP kinase, and p38 MAP kinase-mediated IL-8 production. Human pulmonary vascular endothelial cells that had been preincubated with NAC were stimulated with TNF-α and then the activation of p38 MAP kinase and MKK3/MKK6 in the cells and IL-8 concentrations in the culture supernatants were determined. Intracellular GSH levels increased in NAC-treated cells. NAC attenuated TNF-α-induced activation of p38 MAP kinase and MKK3/MKK6. NAC attenuated p38 MAP kinase-mediated IL-8 production by TNF-α-stimulated cells. These results indicate that the cellular reduction and oxidation (redox) regulated by intracellular GSH is critical for TNF-α-induced activation of p38 MAP kinase pathway and p38 MAP kinase-mediated IL-8 production by human pulmonary vascular endothelial cells, and we emphasize that anti-oxidant therapy is an important strategy for the treatment of acute lung injury. PMID:11156586

N-acetylcysteine attenuates TNF-alpha-induced p38 MAP kinase activation and p38 MAP kinase-mediated IL-8 production by human pulmonary vascular endothelial cells.

PubMed

Hashimoto, S; Gon, Y; Matsumoto, K; Takeshita, I; Horie, T

2001-01-01

1. We have previously shown that tumour necrosis factor-alpha (TNF-alpha) activates p38 mitogen-activated protein (MAP) kinase to produce interleukin-8 (IL-8) by human pulmonary vascular endothelial cells. Reactive oxygen species (ROS) including H(2)O(2) generated by TNF-alpha can act as signalling intermediates for cytokine induction; therefore, scavenging ROS by anti-oxidants is important for the regulation of cytokine production. However, the effect of N-acetylcysteine (NAC), which acts as a precursor of glutathione (GSH) synthesis, on TNF-alpha-induced activation of p38 MAP kinase pathway and p38 MAP kinase-mediated IL-8 production by human pulmonary vascular endothelial cells has not been determined. To clarify these issues, we examined the effect of NAC on TNF-alpha-induced activation of p38 MAP kinase, MAP kinase kinase (MKK) 3 and MKK6 which are upstream regulators of p38 MAP kinase, and p38 MAP kinase-mediated IL-8 production. 2. Human pulmonary vascular endothelial cells that had been preincubated with NAC were stimulated with TNF-alpha and then the activation of p38 MAP kinase and MKK3/MKK6 in the cells and IL-8 concentrations in the culture supernatants were determined. 3. Intracellular GSH levels increased in NAC-treated cells. 4. NAC attenuated TNF-alpha-induced activation of p38 MAP kinase and MKK3/MKK6. 5. NAC attenuated p38 MAP kinase-mediated IL-8 production by TNF-alpha-stimulated cells. 6. These results indicate that the cellular reduction and oxidation (redox) regulated by intracellular GSH is critical for TNF-alpha-induced activation of p38 MAP kinase pathway and p38 MAP kinase-mediated IL-8 production by human pulmonary vascular endothelial cells, and we emphasize that anti-oxidant therapy is an important strategy for the treatment of acute lung injury.

Trauma-induced pemphigus: a case series of 36 patients.

PubMed

Daneshpazhooh, Maryam; Fatehnejad, Mina; Rahbar, Ziba; Balighi, Kamran; Ghandi, Narges; Ghiasi, Maryam; Abedini, Robabeh; Lajevardi, Vahideh; Chams-Davatchi, Cheyda

2016-02-01

Pemphigus is a group of autoimmune diseases characterized by intraepidermal acantholytic blisters. Isomorphic responses, or Koebner phenomenon (KP), defined as the appearance of typical lesions of a disease following trauma are rarely reported in pemphigus. Our aim was to present patients who developed new pemphigus lesions as a result of skin trauma. The medical files of pemphigus patients from the Autoimmune Bullous Diseases Research Center, who had a history of trauma before the onset or flare of their disease, between 1999 and 2013 were reviewed. Thirty-six pemphigus vulgaris (PV) patients had a history of trauma. Thirteen patients developed new-onset PV and the other 23 had previously been diagnosed with PV. Pemphigus lesions developed most often following major surgeries including abdominal, orthopedic, and chest surgeries as well as dental procedures, blunt physical trauma, and skin surgeries. Moreover, post-cataract laser surgery, burns, radiation therapy, and physiotherapy were also shown to induce pemphigus. Mean time between trauma and lesions was 4.7 weeks for recurrent PV and 15.0 weeks for new-onset PV. Unnecessary surgery and blunt trauma should be avoided in pemphigus patients. Furthermore, posttraumatic pemphigus should be suspected in poorly healing surgical wounds and confirmatory biopsies are mandatory. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Institutions and Organizational Change: Reforming New York City's Public School System

ERIC Educational Resources Information Center

Traver, Amy

2006-01-01

This paper reviews New York City Mayor Michael Bloomberg's education reform agenda, "Children first", in the light of organizational theory. I argue that this reform agenda reflects both coercive and mimetic isomorphism, as Bloomberg uses mayoral control to apply business concepts and practices to New York City's public school system.…

Bridging the Gap: Possible Roles and Contributions of Representational Momentum

ERIC Educational Resources Information Center

Hubbard, Timothy L.

2006-01-01

Memory for the position of a moving target is often displaced in the direction of anticipated motion, and this has been referred to as "representational momentum". Such displacement might aid spatial localization by bridging the gap between perception and action, and might reflect a second-order isomorphism between subjective consequences of…

Institutionalisation in a Newly Created Private University

ERIC Educational Resources Information Center

Hodson, Peter; Connolly, Michael; Younes, Said

2008-01-01

Purpose: The purpose of this paper is to examine the introduction of a quality assurance system in a new, private university in Syria, and considers the extent to which the theoretical model based on institutional theory and isomorphism is reflected in practice. Design/methodology/approach: A five year longitudinal study which reviews the design,…

Provincialising the World Culture Theory Debate: Critical Insights from a Margin

ERIC Educational Resources Information Center

Takayama, Keita

2015-01-01

Neo-institutionalist theory of global "isomorphism", or so-called World Culture Theory (WCT), has been much debated in comparative education. One notable feature of the debate is that the vast majority of its participants belong to a handful of closely knit comparative education communities. Ironically enough then, a debate that…

Graphical Representations and the Perception of Motion: Integrating Isomorphism through Kinesthesia into Physics Instruction

ERIC Educational Resources Information Center

Espinoza, Fernando

2015-01-01

The incorporation of engaging and meaningful learning experiences is essential for the enhancement of critical thinking and the development of scientific literacy. The study engaged several groups of students in activities designed to elicit their understanding of a graphical representation of motion, and to determine the kinesthetic effect of…

Representation Use and Strategy Choice in Physics Problem Solving

ERIC Educational Resources Information Center

De Cock, Mieke

2012-01-01

In this paper, we examine student success on three variants of a test item given in different representational formats (verbal, pictorial, and graphical), with an isomorphic problem statement. We confirm results from recent papers where it is mentioned that physics students' problem-solving competence can vary with representational format and that…

General Open Systems Theory and the Substrata-Factor Theory of Reading.

ERIC Educational Resources Information Center

Kling, Martin

This study was designed to extend the generality of the Substrata-Factor Theory by two methods of investigation: (1) theoretically, to establish the validity of the hypothesis that an isomorphic relationship exists between the Substrata-Factor Theory and the General Open Systems Theory, and (2) experimentally, to discover through a series of…

General Open Systems Theory and the Substrata-Factor Theory of Reading.

ERIC Educational Resources Information Center

Kling, Martin

This study was designed to extend the generality of the Substrata-Factor Theory by two methods of investigation: (1) theoretically, to est"blish the validity of the hypothesis that an isomorphic relationship exists between the Substrata-Factor Theory and the General Open Systems Theory, and (2) experimentally, to disc"ver through a…

Global Isomorphism and Governance Reform in Chinese Higher Education

ERIC Educational Resources Information Center

Cai, Yuzhuo

2010-01-01

In the past three decades, higher education reforms have taken place almost everywhere in the world, and governance or the way that higher education is or should be coordinated has become a global topic. The governance reform in Chinese higher education emerged against such a background. The current studies on Chinese higher education reforms…

Having the Memory of an Elephant: Long-Term Retrieval and the Use of Analogues in Problem Solving

ERIC Educational Resources Information Center

Chen, Zhe; Mo, Lei; Honomichl, Ryan

2004-01-01

The authors report 4 experiments exploring long-term analogical transfer from problem solutions in folk tales participants heard during childhood, many years before encountering the target problems. Substantial culture-specific analogical transfer was found when American and Chinese participants' performance was compared on isomorphs of problems…

Teachers' Work: Institutional Isomorphism and Cultural Variation in the U.S., Germany, and Japan.

ERIC Educational Resources Information Center

LeTendre, Gerald K.; Baker, David P.; Akiba, Motoko; Goesling, Brian; Wiseman, Alex

2001-01-01

Used data from the Third International Math-Science Study to examine the working conditions and beliefs of Japanese, German, and United States teachers. Core teaching practices and teacher beliefs showed little national variation, but other aspects of teachers' work showed variation. Models of national cultures of learning may overemphasize…

Hard and Soft Governance: The Journey from Transnational Agencies to School Leadership

ERIC Educational Resources Information Center

Moos, Lejf

2009-01-01

The governance and leadership at transnational, national and school level seem to be converging into a number of isomorphic forms as we see a tendency towards substituting "hard" forms of governance, that are legally binding, with "soft" forms based on persuasion and advice. This article analyses and discusses governance forms…

Innovation in Educational Markets: An Organizational Analysis of Private Schools in Toronto

ERIC Educational Resources Information Center

Davies, Scott; Quirke, Linda

2005-01-01

This study examines whether new private schools are innovative, drawing on theories of markets and institutions. Choice advocates claim that markets spark innovation, while institutional theory suggests that isomorphic forces will limit novel school forms. Using qualitative data from third sector private schools in Toronto, three hypotheses about…

Academic Work from a Comparative Perspective: A Survey of Faculty Working Time across 13 Countries

ERIC Educational Resources Information Center

Bentley, Peter James; Kyvik, Svein

2012-01-01

Sociological institutional theory views universities as model driven organizations. The world's stratification system promotes conformity, imitation and isomorphism towards the "best" university models. Accordingly, academic roles may be locally shaped in minor ways, but are defined and measured explicitly in global terms. We test this proposition…

Material Mediation: Tools and Representations Supporting Collaborative Problem-Solving Discourse

ERIC Educational Resources Information Center

Katic, Elvira K.; Hmelo-Silver, Cindy E.; Weber, Keith H.

2009-01-01

This study investigates how a variety of resources mediated collaborative problem solving for a group of preservice teachers. The participants in this study completed mathematical, combinatorial tasks and then watched a video of a sixth grader as he exhibited sophisticated reasoning to recognize the isomorphic structure of these problems. The…

The Effects of Environmental Characteristics on the Structure of Hospital Clusters.

ERIC Educational Resources Information Center

Fennell, Mary L.

1980-01-01

The population ecology view that variation in sets or clusters of organizations should be isomorphic with variation in cluster environment was used to explain structural variation among hospital clusters. Cluster differentiation seems to be casually affected by range of services, average hospital size, and the periodic closing of hospitals.…

The Globalizing Labor Market in Education: Teachers as Cultural Ambassadors or Agents of Institutional Isomorphism?

ERIC Educational Resources Information Center

Brown, Kara D.; Stevick, Doyle

2014-01-01

Institutional isomorphists and other proponents of world culture theory argue that schools around the world are converging in many ways, whereas anthropologists and others question this conclusion, often arguing that local cultural differences belie superficial similarities. These viewpoints are not merely academic explanations of the spread and…

Sixth Form Colleges: Isomorphism, Adaptation and the New Education Market

ERIC Educational Resources Information Center

Stoten, David William

2014-01-01

The English education sector is undergoing major restructuring with the coalition government placing great emphasis on two key principles of policy: deregulation and marketisation. This development follows on two decades in which the British state has sought to raise performance levels and reduce costs through a variety of policies that are drawn…

Recognition of VLSI Module Isomorphism

DTIC Science & Technology

1990-03-01

forthforth->next; 6.5 else{ prev4=prev4->next; forth=forth->next; if (header-. nenI ->tai==third){ header-.nevrI->tail=prev3; prev3->next=NULL; end...end=TRUE; if (header-. nenI ->head=third){ header-.newn->head=third->next; I if((third!=prev3)&&(finished!=TRUE)){ prev3->next=prev3->next->next; third

Approximate Subgraph Isomorphism for Image Localization (Author’s Manuscript)

DTIC Science & Technology

2016-02-18

a working database for feature matching methods is nearly impossible to generate. In a proof of feasibility, Bansal et. al. [2] claim that overhead...of images in mountainous terrain. In Computer Vision–ECCV 2012, pages 517–530. Springer, 2012. 1 [2] M. Bansal , H. S. Sawhney, H. Cheng, and K

Advances in Graduate Marketing Curriculum: Paying Attention to Ethical, Social, and Sustainability Issues

ERIC Educational Resources Information Center

Weber, James

2013-01-01

This research explores the impact of coercive, mimetic, and normative isomorphic pressures on the coverage and offering of courses addressing ethical, social, and sustainability issues (ESSI) in business schools' graduate marketing curricula. Data from the Aspen Institute's Beyond Grey Pinstripes program are analyzed to detect if significant…

The Stranger within: Luxembourg's Early School System as a European Prototype of Nationally Legitimized International Blends (ca. 1794-1844)

ERIC Educational Resources Information Center

Thyssen, Geert

2013-01-01

This comparative analysis of Luxembourg's early school (law) system reveals the extent to which European school systems reflect "national-cultural idiosyncrasies" apart from "structural isomorphism". It first examines the legal soil into which the Luxembourg school system was implanted. Legislative pendular swings, reflecting…

How Children Solve Environmental Problems: Using Computer Simulations To Investigate Systems Thinking.

ERIC Educational Resources Information Center

Sheehy, N. P.; Wylie, J. W.; McGuinness, C.; Orchard, G.

2000-01-01

Describes the development and use of two computer simulations for investigating systems thinking and environmental problem-solving in children (n=92). Finds that older children outperformed younger children, who tended to exhibit magical thinking. Suggests that seemingly isomorphic environmental problems may not be interpreted as such by children.…

A Characterization of Banach Spaces Containing l1

PubMed Central

Rosenthal, Haskell P.

1974-01-01

It is proved that a Banach space contains a subspace isomorphic to l1 if (and only if) it has a bounded sequence with no weak-Cauchy subsequence. The proof yields that a sequence of subsets of a given set has a subsequence that is either convergent or Boolean independent. PMID:16592162

The Impact of Sector on School Organizations: Institutional and Market Logics

ERIC Educational Resources Information Center

Davies, Scott; Quirke, Linda

2007-01-01

Drawing on new institutional and market theories, this article derives three hypotheses for the effects of markets on educational organizations: They (1) weaken formal structures, (2) reverse tendencies toward isomorphism, and (3) force schools to recouple and compete via performance indicators. These ideas are investigated with data on private…

The New Institutionalism: Mismatches with Private Higher Education's Global Growth. PROPHE Working Paper Series. WP No. 3

ERIC Educational Resources Information Center

Levy, Daniel C.

2004-01-01

Spectacular contemporary growth in private higher education challenges the "new institutionalism" and its emphasis on "isomorphism." The growth brings great inter-organizational distinctiveness and is linked to technically rational competition. Findings about this growth and distinctiveness lead us to re-assess and revise…

From Planck Constant to Isomorphicity Through Justice Paradox

NASA Astrophysics Data System (ADS)

Hidajatullah-Maksoed, Widastra

2015-05-01

Robert E. Scott in his ``Chaos theory and the Justice Paradox'', William & Mary Law Review, v 35, I 1, 329 (1993) wrotes''...As we approach the 21-st Century, the signs of social disarray are everywhere. Social critics observe the breakdown of core structure - the nuclear family, schools, neighborhoods & political groups''. For completions for ``soliton'' first coined by Morikazu TODA, comparing the ``Soliton on Scott-Russell aqueduct on the Union Canal near Heriot-WATT University, July 12, 1995 to Michael Stock works: ``a Fine WATT-Balance: Determination of Planck constant & Redefinition of Kilogram'', January 2011, we can concludes the inherencies between `chaos' & `soliton'. Further through ``string theory'' from Michio KAKU sought statements from Peter Mayr: Stringy world brane & Exponential hierarchy'', JHEP 11 (2000): ``if the 5-brane is embedded in flat 10-D space time, the 6-D Planck mass on the brane is infinite'' who also describes the relation of isomorphicity & ``string theory'', from whom denotes the smart city. Replace this text with your abstract body. Incredible acknowledgments to HE. Mr. Drs. P. SWANTORO & HE. Mr. Dr-HC Jakob OETAMA.

Purification, crystallization and X-ray diffraction analysis of the C-terminal protease domain of Venezuelan equine encephalitis virus nsP2

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

Russo, Andrew T.; Watowich, Stanley J., E-mail: watowich@xray.utmb.edu

2006-06-01

The C-terminal protease domain of Venezuelan equine encephalitis virus (VEEV) nsP2 has been overexpressed in E. coli, purified and successfully crystallized. Native crystals diffract to beyond 2.5 Å resolution and isomorphous heavy-atom derivatives suitable for phase analysis have been identified. The C-terminal region of Venezuelan equine encephalitis virus (VEEV) nsP2 is responsible for proteolytic processing of the VEEV polyprotein replication complex. This action regulates the activity of the replication complex and is essential for viral replication, thus making nsP2 a very attractive target for development of VEEV therapeutics. The 338-amino-acid C-terminal region of VEEV nsP2 has been overexpressed in Escherichiamore » coli, purified and crystallized. Crystals diffract to beyond 2.5 Å resolution and belong to the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1}. Isomorphous heavy-atom derivatives suitable for phase analysis have been obtained and work on building a complete structural model is under way.« less

Localization of sclerotic-type chronic graft-vs-host disease to sites of skin injury: potential insight into the mechanism of isomorphic and isotopic responses.

PubMed

Martires, Kathryn J; Baird, Kristin; Citrin, Deborah E; Hakim, Fran T; Pavletic, Steven Z; Cowen, Edward W

2011-09-01

The mechanisms responsible for the variable manifestations of chronic cutaneous graft-vs-host disease (cGVHD) are poorly understood. Localization of sclerotic-type chronic graft-vs-host disease to sites of skin injury (isomorphic and isotopic responses), a recognized phenomenon in morphea, suggests a potential common pathway between cGVHD and other sclerotic skin conditions. Four cases of sclerotic-type cGVHD developed at the site of disparate skin injuries (ionizing radiotherapy, repeated needle sticks, central catheter site, and varicella-zoster virus infection). We review the spectrum of previously reported cases of sclerotic and nonsclerotic cGVHD relating to external forces on the skin. Localization of sclerotic-type cGVHD may occur after many types of skin injury, including UV and ionizing radiotherapy, needle sticks, viral infection, and pressure or friction. Recognition of this phenomenon may be helpful for the early diagnosis of sclerotic disease. Recent insights into the immunological consequences of minor skin injury may provide important clues to the underlying pathogenesis of cGVHD-mediated skin disease.

QuateXelero: An Accelerated Exact Network Motif Detection Algorithm

PubMed Central

Khakabimamaghani, Sahand; Sharafuddin, Iman; Dichter, Norbert; Koch, Ina; Masoudi-Nejad, Ali

2013-01-01

Finding motifs in biological, social, technological, and other types of networks has become a widespread method to gain more knowledge about these networks’ structure and function. However, this task is very computationally demanding, because it is highly associated with the graph isomorphism which is an NP problem (not known to belong to P or NP-complete subsets yet). Accordingly, this research is endeavoring to decrease the need to call NAUTY isomorphism detection method, which is the most time-consuming step in many existing algorithms. The work provides an extremely fast motif detection algorithm called QuateXelero, which has a Quaternary Tree data structure in the heart. The proposed algorithm is based on the well-known ESU (FANMOD) motif detection algorithm. The results of experiments on some standard model networks approve the overal superiority of the proposed algorithm, namely QuateXelero, compared with two of the fastest existing algorithms, G-Tries and Kavosh. QuateXelero is especially fastest in constructing the central data structure of the algorithm from scratch based on the input network. PMID:23874498

The Construction of {P}_{2}\\vartriangleright H-antimagic graph using smaller edge-antimagic vertex labeling

NASA Astrophysics Data System (ADS)

Prihandini, Rafiantika M.; Agustin, I. H.; Dafik

2018-04-01

In this paper we use simple and non trivial graph. If there exist a bijective function g:V(G) \\cup E(G)\\to \\{1,2,\\ldots,|V(G)|+|E(G)|\\}, such that for all subgraphs {P}2\\vartriangleright H of G isomorphic to H, then graph G is called an (a, b)-{P}2\\vartriangleright H-antimagic total graph. Furthermore, we can consider the total {P}2\\vartriangleright H-weights W({P}2\\vartriangleright H)={\\sum }v\\in V({P2\\vartriangleright H)}f(v)+{\\sum }e\\in E({P2\\vartriangleright H)}f(e) which should form an arithmetic sequence {a, a + d, a + 2d, …, a + (n ‑ 1)d}, where a and d are positive integers and n is the number of all subgraphs isomorphic to H. Our paper describes the existence of super (a, b)-{P}2\\vartriangleright H antimagic total labeling for graph operation of comb product namely of G=L\\vartriangleright H, where L is a (b, d*)-edge antimagic vertex labeling graph and H is a connected graph.

A non-commutative *-algebra of Borel functions

NASA Astrophysics Data System (ADS)

Hart, Robert

To the pair (E, sigma), where E is a countable Borel equivalence relation on a standard Borel space ( X, A ) and sigma a normalized Borel T -valued 2-cocycle on E, we associate a sequentially weakly closed Borel *-algebra B*r (E, sigma), contained in the bounded linear operators on ℓ2(E). Associated to B*r (E, sigma) is a natural (Borel) Cartan subalgebra (Definition 6.4.10) L( Bo (X)) isomorphic to the bounded Borel functions on X. Then L( Bo (X)) and its normalizer (the set of the unitaries u ∈ B*r (E, sigma) such that u* fu ∈ L( Bo (X)), f ∈ L( Bo (X))) countably generates the Borel *-algebra B*r (E, sigma). In this thesis, we study B*r (E, sigma) and in particular prove that: i) If E is smooth, then B*r (E, sigma) is a type I Borel *-algebra (Definition 6.3.10). ii) If E is a hyperfinite, then B*r (E, sigma) is a Borel AF-algebra (Definition 7.5.1). iii) Generalizing Kumjian's definition, we define a Borel twist Gamma over E and its associated sequentially closed Borel *-algebra B*r (Gamma). iv) Let a Borel Cartan pair ( B,B0 ) denote a sequentially closed Borel *-algebra B with a Borel Cartan subalgebra B0 , where B is countably B0 -generated. Generalizing Feldman-Moore's result, we prove that any pair ( B,B0 ) can be realized uniquely as a pair ( B*r (E, sigma), L( Bo (X))). Moreover, we show that the pair ( B*r (E), L( Bo (X))) is a complete invariant of the countable Borel equivalence relation E. v) We prove a Krieger type theorem, by showing that two aperiodic hyperfinite countable equivalence relations are isomorphic if and only if their associated Borel *-algebras B*r (E1) and B*r (E2) are isomorphic.

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

Wang, Shengyan; Shan, Liang; Fan, Yong

Three isomorphic lanthanide metal-organic frameworks (Ln-MOFs) [LnL(H{sub 2}O){sub 2}]·2H{sub 2}O (Ln=Tb for 1, Eu for 2, Gd for 3) have been constructed from flexible organic ligand 4-(2-carboxyphenoxy)benzene-1,3-dioic acid (H{sub 3}L). They exhibit two-dimensional (2D) layered structure with the rhombus windows along the b axis. This network can be described as a shubnikov plane net with Schäfli symbol of (4{sup 3}){sub 2}(4{sup 6}.6{sup 6}.8{sup 3}). Solid state luminescent studies indicate that 1 and 2 show the characteristic red, and green emissions of the corresponding Ln{sup 3+} ions, respectively, while 3 exhibits blue emission arising from the organic ligand. Then by adjustingmore » the relative amounts of different luminescent components into the well-defined host framework, a series of new co-doped Ln-MOF, Tb{sub 1−x}Eu{sub x}L (4) (x refers to the molar ratios of Eu{sup 3+} and Tb{sup 3+}), with tunable luminescence have been fabricated. The luminescent color of 4 can be tuned from green to red due to the energy transfer from the Tb{sup 3+} to Eu{sup 3+} ions by changing the doping concentration of the Eu{sup 3+} ions. In addition, 2 exhibits good stability in different solvents and excellent fluorescence sensing for small molecules, especially for CH{sub 3}CN and nitrobenzene. - Graphical abstract: A series of isomorphic 2D layered Ln-MOFs have been constructed from flexible tricarboxylic ligand, showing tunable luminescence and excellent fluorescence sensing for small molecules, respectively. - Highlights: • Three isomorphic 2D layered Ln-MOFs were constructed by flexible tricarboxylic acid. • A series of Eu{sup 3+}/Tb{sup 3+} doped Ln-MOF 4 were fabricated and showed tunable luminescence. • Ln-MOF 2 exhibited excellent fluorescence sensing for small molecules.« less

MAP KINASE ERK 1/2 INHIBITORS INDUCE DYSMORPHOLOGY IN MOUSE WHOLE EMBRYO CULTURE

EPA Science Inventory

ROSEN, M.B. and E. S. HUNTER. Reproductive Toxicology Division, NHEERL, ORD, U.S. EPA, Research Triangle Park, North Carolina. MAP kinase Erk1/2 inhibitors induce dysmorphology in mouse whole embryo culture.

MAP Kinase signal transduction is associated with a variety ...

Motion-induced error reduction by combining Fourier transform profilometry with phase-shifting profilometry.

PubMed

Li, Beiwen; Liu, Ziping; Zhang, Song

2016-10-03

We propose a hybrid computational framework to reduce motion-induced measurement error by combining the Fourier transform profilometry (FTP) and phase-shifting profilometry (PSP). The proposed method is composed of three major steps: Step 1 is to extract continuous relative phase maps for each isolated object with single-shot FTP method and spatial phase unwrapping; Step 2 is to obtain an absolute phase map of the entire scene using PSP method, albeit motion-induced errors exist on the extracted absolute phase map; and Step 3 is to shift the continuous relative phase maps from Step 1 to generate final absolute phase maps for each isolated object by referring to the absolute phase map with error from Step 2. Experiments demonstrate the success of the proposed computational framework for measuring multiple isolated rapidly moving objects.

Metalloproteinase-dependent transforming growth factor-alpha release mediates neurotensin-stimulated MAP kinase activation in human colonic epithelial cells.

PubMed

Zhao, Dezheng; Zhan, Yanai; Koon, Hon Wai; Zeng, Huiyan; Keates, Sarah; Moyer, Mary P; Pothoulakis, Charalabos

2004-10-15

Expression of the neuropeptide neurotensin (NT) and its high affinity receptor (NTR1) is increased during the course of Clostridium difficile toxin A-induced acute colitis, and NTR1 antagonism attenuates the severity of toxin A-induced inflammation. We recently demonstrated in non-transformed human colonic epithelial NCM460 cells that NT treatment caused activation of a Ras-mediated MAP kinase pathway that significantly contributes to NT-induced interleukin-8 (IL-8) secretion. Here we used NCM460 cells, which normally express low levels of NTR1, and NCM460 cells stably transfected with NTR1 to identify the upstream signaling molecules involved in NT-NTR1-mediated MAP kinase activation. We found that inhibition of the epidermal growth factor receptor (EGFR) by either an EGFR neutralizing antibody or by its specific inhibitor AG1478 (0.2 microm) blocked NT-induced MAP kinase activation. Moreover, NT stimulated tyrosine phosphorylation of the EGFR, and pretreatment with a broad spectrum metalloproteinase inhibitor batimastat reduced NT-induced MAP kinase activation. Using neutralizing antibodies against the EGFR ligands EGF, heparin-binding-EGF, transforming growth factor-alpha (TGFalpha), or amphiregulin we have shown that only the anti-TGFalpha antibody significantly decreases NT-induced phosphorylation of EGFR and MAP kinases. Furthermore, inhibition of the EGF receptor by AG1478 significantly reduced NT-induced IL-8 promoter activity and IL-8 secretion. This is the first report demonstrating that NT binding to NTR1 transactivates the EGFR and that this response is linked to NT-mediated proinflammatory signaling. Our findings indicate that matrix metalloproteinase-mediated release of TGFalpha and subsequent EGFR transactivation triggers a NT-mediated MAP kinase pathway that leads to IL-8 gene expression in human colonic epithelial cells.

Experimental colitis is exacerbated by concomitant infection with Mycobacterium avium ssp. paratuberculosis.

PubMed

Suwandi, Abdulhadi; Bargen, Imke; Roy, Bishnudeo; Pils, Marina C; Krey, Martina; Zur Lage, Susanne; Basler, Tina; Rohde, Manfred; Falk, Christine S; Hornef, Mathias W; Goethe, Ralph; Weiss, Siegfried

2014-11-01

Crohn's disease (CD) is a chronic inflammatory disorder of the human gastrointestinal tract. Although genetic, immunological, environmental, and bacterial factors have been implicated, the pathogenesis is incompletely understood. The histopathological appearance of CD strikingly resembles Johne's disease, a ruminant inflammatory bowel disease, caused by Mycobacterium avium ssp. paratuberculosis (MAP), but a causative role of MAP in CD has not been established. In this work, we hypothesized that MAP might exacerbate an already existing intestinal disease. We combined dextran sulfate sodium (DSS)-induced colitis with MAP infection in mice and monitored the immune response and bacterial count in different organs. An increased size of liver and spleen was observed in DSS-treated and MAP-infected animals (DSS + MAP) as compared with DSS-treated uninfected (DSS + PBS) mice. Similarly, DSS treatment increased the number and size of MAP-induced liver granulomas and enhanced the MAP counts in enteric tissue. MAP infection in turn delayed the mucosal healing of DSS-induced tissue damage. Finally, high numbers of MAP were found in mesenteric fat tissue causing large granuloma and necrotic regions. Taken together, we present an in vivo model to study the role of MAP infection in CD. Our results confirm the hypothesis that MAP is able to exacerbate existing intestinal inflammation.

AT1 receptor-mediated uptake of angiotensin II and NHE-3 expression in proximal tubule cells through a microtubule-dependent endocytic pathway.

PubMed

Li, Xiao C; Hopfer, Ulrich; Zhuo, Jia L

2009-11-01

Angiotensin II (ANG II) is taken up by proximal tubule (PT) cells via AT1 (AT1a) receptor-mediated endocytosis, but the underlying cellular mechanisms remain poorly understood. The present study tested the hypothesis that the microtubule- rather than the clathrin-dependent endocytic pathway regulates AT1-mediated uptake of ANG II and ANG II-induced sodium and hydrogen exchanger-3 (NHE-3) expression in PT cells. The expression of AT1 receptors, clathrin light (LC) and heavy chain (HC) proteins, and type 1 microtubule-associated proteins (MAPs; MAP-1A and MAP-1B) in PT cells were knocked down by their respective small interfering (si) RNAs before AT1-mediated FITC-ANG II uptake and ANG II-induced NHE-3 expression were studied. AT1 siRNAs inhibited AT1 expression and blocked ANG II-induced NHE-3 expression in PT cells, as expected (P < 0.01). Clathrin LC or HC siRNAs knocked down their respective proteins by approximately 90% with a peak response at 24 h, and blocked the clathrin-dependent uptake of Alexa Fluor 594-transferrin (P < 0.01). However, neither LC nor HC siRNAs inhibited AT1-mediated uptake of FITC-ANG II or affected ANG II-induced NHE-3 expression. MAP-1A or MAP-1B siRNAs markedly knocked down MAP-1A or MAP-1B proteins in a time-dependent manner with peak inhibitions at 48 h (>76.8%, P < 0.01). MAP protein knockdown resulted in approximately 52% decreases in AT1-mediated FITC-ANG II uptake and approximately 66% decreases in ANG II-induced NHE-3 expression (P < 0.01). These effects were associated with threefold decreases in ANG II-induced MAP kinases ERK 1/2 activation (P < 0.01), but not with altered AT1 expression or clathrin-dependent transferrin uptake. Both losartan and AT1a receptor deletion in mouse PT cells completely abolished the effects of MAP-1A knockdown on ANG II-induced NHE-3 expression and activation of MAP kinases ERK1/2. Our findings suggest that the alternative microtubule-dependent endocytic pathway, rather than the canonical clathrin-dependent pathway, plays an important role in AT1 (AT1a)-mediated uptake of extracellular ANG II and ANG II-induced NHE-3 expression in PT cells.

Isomorphous rare-earth tris[bis(2,6-diisopropylphenyl) phosphate] complexes and their catalytic properties in 1,3-diene polymerization and in the inhibited oxidation of polydimethylsiloxane.

PubMed

Minyaev, Mikhail E; Tavtorkin, Alexander N; Korchagina, Sof'ya A; Bondarenko, Galina N; Churakov, Andrei V; Nifant'ev, Ilya E

2018-05-01

Crystals of mononuclear tris[bis(2,6-diisopropylphenyl) phosphato-κO]pentakis(methanol-κO)lanthanide methanol monosolvates of lanthanum, [La(C 24 H 34 O 4 P) 3 (CH 3 OH) 5 ]·CH 3 OH, (1), cerium, [Ce(C 24 H 34 O 4 P) 3 (CH 3 OH) 5 ]·CH 3 OH, (2), and neodymium, [Nd(C 24 H 34 O 4 P) 3 (CH 3 OH) 5 ]·CH 3 OH, (3), have been obtained by reactions between LnCl 3 (H 2 O) n (n = 6 or 7) and lithium bis(2,6-diisopropylphenyl) phosphate in a 1:3 molar ratio in methanol media. Compounds (1)-(3) crystallize in the monoclinic P2 1 /c space group and have isomorphous crystal structures. All three bis(2,6-diisopropylphenyl) phosphate ligands display a κO-monodentate coordination mode. The coordination number of the metal atom is 8. Each [Ln{O 2 P(O-2,6- i Pr 2 C 6 H 3 ) 2 } 3 (CH 3 OH) 5 ] molecular unit exhibits four intramolecular O-H...O hydrogen bonds, forming six-membered rings. The unit forms two intermolecular O-H...O hydrogen bonds with one noncoordinating methanol molecule. All six hydroxy H atoms are involved in hydrogen bonding within the [Ln{O 2 P(O-2,6- i Pr 2 C 6 H 3 ) 2 } 3 (CH 3 OH) 5 ]·CH 3 OH unit. This, along with the high steric hindrance induced by the three bulky diaryl phosphate ligands, prevents the formation of a hydrogen-bond network. Complexes (1)-(3) exhibit disorder of two of the isopropyl groups of the phosphate ligands. The cerium compound (2) demonstrates an essential catalytic inhibition in the thermal decomposition of polydimethylsiloxane in air at 573 K. Catalytic systems based on the neodymium complex tris[bis(2,6-diisopropylphenyl) phosphato-κO]neodymium, (3'), which was obtained as a dry powder of (3) upon removal of methanol, display a high catalytic activity in isoprene and butadiene polymerization.

Symmetry of extremely floppy molecules: Molecular states beyond rotation-vibration separation

NASA Astrophysics Data System (ADS)

Schmiedt, Hanno; Schlemmer, Stephan; Jensen, Per

2015-10-01

Traditionally, molecules are theoretically described as near-static structures rotating in space. Vibrational motion causing small structural deformations induces a perturbative treatment of the rotation-vibration interaction, which fails in highly fluxional molecules, where all vibrational motions have amplitudes comparable in size to the linear dimensions of the molecule. An example is protonated methane (CH 5+ ) [P. Kumar and D. Marx, Phys. Chem. Chem. Phys. 8, 573 (2006); Z. Jin et al., J. Phys. Chem. A 110, 1569 (2006); and A. S. Petit et al., J. Phys. Chem. A 118, 7206 (2014)]. For these molecules, customary theory fails to simulate reliably even the low-energy spectrum [T. Oka, Science 347, 1313-1314 (2015) and O. Asvany et al., Science 347, 1346-1349 (2015)]. Within the traditional view of rotation and vibration being near-separable, rotational and vibrational wavefunctions can be symmetry classified separately in the molecular symmetry (MS) group [P. Bunker and P. Jensen, Molecular Symmetry and Spectroscopy, NRC Monograph Publishing Program (NRC Research Press, 2006)]. In this article, we discuss a fundamental group theoretical approach to the problem of determining the symmetries of molecular rotation-vibration states. We will show that all MS groups discussed so far are isomorphic to subgroups of the special orthogonal group in three dimensions SO(3). This leads to a group theoretical foundation of the technique of equivalent rotations [H. Longuet-Higgins, Mol. Phys. 6, 445 (1963)]. The group G240 (the MS group of protonated methane) represents, to the best of our knowledge, the first example of a MS group which is not isomorphic to a subgroup of SO(3) (nor of O(3) or of SU(2)). Because of this, a separate symmetry classification of vibrational and rotational wavefunctions becomes impossible in this MS group, consistent with the fact that a decoupling of vibrational and rotational motion is impossible. We discuss here the consequences of this. In conclusion, we show that the prototypical, extremely floppy molecule CH 5+ represents a new class of molecules, where customary group theoretical methods for determining selection rules and spectral assignments fail so that new methods have to be developed.

Students' Visualization of Diagrams Representing the Human Circulatory System: The Use of Spatial Isomorphism and Representational Conventions

ERIC Educational Resources Information Center

Cheng, Maurice M. W.; Gilbert, John K.

2015-01-01

This study investigated students' interpretation of diagrams representing the human circulatory system. We conducted an interview study with three students aged 14-15 (Year 10) who were studying biology in a Hong Kong school. During the interviews, students were asked to interpret diagrams and relationships between diagrams that represented…

Understanding Quaternions and the Dirac Belt Trick

ERIC Educational Resources Information Center

Staley, Mark

2010-01-01

The Dirac belt trick is often employed in physics classrooms to show that a 2n rotation is not topologically equivalent to the absence of rotation whereas a 4n rotation is, mirroring a key property of quaternions and their isomorphic cousins, spinors. The belt trick can leave the student wondering if a real understanding of quaternions and spinors…

Creative Design of Digital Cognitive Games: Application of Cognitive Toys and Isomorphism

ERIC Educational Resources Information Center

Sedig, Kamran; Haworth, Robert

2012-01-01

Digital cognitive games (DCGs) are games whose primary purpose is to mediate (i.e., support, develop, and enhance) cognitive activities such as problem solving, decision making, planning, and critical reasoning. As these games increase in popularity and usage, more attention should be paid to their design. Currently, there is a lack of design…

New applications of maximum likelihood and Bayesian statistics in macromolecular crystallography.

PubMed

McCoy, Airlie J

2002-10-01

Maximum likelihood methods are well known to macromolecular crystallographers as the methods of choice for isomorphous phasing and structure refinement. Recently, the use of maximum likelihood and Bayesian statistics has extended to the areas of molecular replacement and density modification, placing these methods on a stronger statistical foundation and making them more accurate and effective.

Institutional Pressures and Isomorphic Change: The Case of New York City's Department of Education

ERIC Educational Resources Information Center

Carolan, Brian V.

2008-01-01

Many urban school districts have recently implemented sweeping reforms that alter the ways in which educational services are administered. The environment in which these reforms are embedded is increasingly and more directly tied to core political institutions and business elites. Hence, as this dependence has grown, districts have become more…

Changing Places: A Cross-Language Perspective on Frequency and Family Size in Dutch and Hebrew

ERIC Educational Resources Information Center

Moscoso del Prado Martin, Fermin; Deutsch, Avital; Frost, Ram; Schreuder, Robert; De Jong, Nivja H.; Baayen, R. Harald

2005-01-01

This study uses the morphological family size effect as a tool for exploring the degree of isomorphism in the networks of morphologically related words in the Hebrew and Dutch mental lexicon. Hebrew and Dutch are genetically unrelated, and they structure their morphologically complex words in very different ways. Two visual lexical decision…

Exploring the Interweaving of Contrary Currents: Transnational Policy Enactment and Path-Dependent Policy Implementation in Australia and Japan

ERIC Educational Resources Information Center

Takayama, Keita

2012-01-01

This article explores the neo-institutional theory of global policy convergence, or "isomorphism", by comparatively examining one of its most recent manifestations--the global diffusion of national standardised testing--in Australia and Japan. By understanding the particular configurations of national testing as being conditioned by both…

Biochemical genetic variation in the Family Simuliidae: electrophoretic identification of the human biter in the isomorphic Simulium jenningsi group

Treesearch

Bernie May; Leah S. Bauer; Robert L. Vadas; Jeffrey Granett

1977-01-01

This paper describes inter- and intraspecific protein variation in the 3 closely related species of the Simulium jenningsi black fly group, S. jenningsi Malloch, S. Nyssa Stone and Snoddy, and S. n. sp. P. Snoddy and Bauer. Variation is described at single loci coding for the enzymes,...

Brominated carbon black: An EDXD study

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

Carbone, Marilena; Gontrani, Lorenzo, E-mail: lorenzo.gontrani@uniroma1.it

2014-06-19

An energy dispersive X-Ray study of pure and brominated carbon black was carried out. The analysis of the diffraction patterns reveals that the low bromine load (ca.1% mol) is trapped into the structure, without significantly modifying it. This allows the application of the difference methods, widely tested for electrolyte solutions, inorganic matrices containing metals and isomorphic substitutions.

Word Learning Emerges from the Interaction of Online Referent Selection and Slow Associative Learning

ERIC Educational Resources Information Center

McMurray, Bob; Horst, Jessica S.; Samuelson, Larissa K.

2012-01-01

Classic approaches to word learning emphasize referential ambiguity: In naming situations, a novel word could refer to many possible objects, properties, actions, and so forth. To solve this, researchers have posited constraints, and inference strategies, but assume that determining the referent of a novel word is isomorphic to learning. We…

Method of storing radioactive wastes using modified tobermorite

DOEpatents

Komarneni, Sridhar; Roy, Della M.

1985-01-01

A new cation exchanger is a modified tobermorite containing aluminum isomorphously substituted for silicon and containing sodium or potassium. The exchanger is selective for lead, rubidium, cobalt and cadmium and is selective for cesium over calcium or sodium. The tobermorites are compatable with cement and are useful for the long-term fixation and storage of radioactive nuclear wastes.

Twenty-Four-Month-Olds' Perception of Word-Medial Onsets and Codas

ERIC Educational Resources Information Center

Wang, Yuanyuan; Seidl, Amanda

2016-01-01

Recent work has shown that children have detailed phonological representations of consonants at both word-initial and word-final edges. Nonetheless, it remains unclear whether onsets and codas are equally represented by young learners since word edges are isomorphic with syllable edges in this work. The current study sought to explore toddler's…

Ion-exchange material and method of storing radioactive wastes

DOEpatents

Komarneni, S.; Roy, D.M.

1983-10-31

A new cation exchanger is a modified tobermorite containing aluminum isomorphously substituted for silicon and containing sodium or potassium. The exchanger is selective for lead, rubidium, cobalt, and cadmium and is selective for cesium over calcium or sodium. The tobermorites are compatible with cement and are useful for the long-term fixation and storage of radioactive nuclear wastes.

Similarities and Differences in the Organizational Characteristics of Charter Schools: A Test of Institutional Isomorphism and Strategy Positioning Theories

ERIC Educational Resources Information Center

Sweet, Thomas

2013-01-01

Charter schools, independent public schools which operate through a system of contracts with public agencies, are heavily promoted as a means of improving the nation's traditional public education system. Managed as private enterprises, these schools compete for students through the implementation of market-style practices. Popularly viewed as…

Darwinism Then and Now: The Divide over Form and Function

ERIC Educational Resources Information Center

Ruse, Michael

2010-01-01

As biologists have recognized since Aristotle, there are two complementary ways of looking at organisms: one can think of them from the viewpoint of homology, asking about the isomorphisms between different organisms and even within the organisms themselves; or one can think of them from the viewpoint of adaptation or final cause, asking about the…

Retrolife and the Pawns Neighbors

ERIC Educational Resources Information Center

Elran, Yossi

2012-01-01

One of Martin Gardner's most famous columns introduced John Conway's game of Life. The inverse problem, finding a previous generation in the Game of Life given some extra constraints, was introduced a few years ago and is referred to as Retrolife. In this paper we present a puzzle played on a chessboard that is isomorphic to a variation of…

Coordination polymer-derived nano-sized zinc ferrite with excellent performance in nitro-explosive detection.

PubMed

Singha, Debal Kanti; Mahata, Partha

2017-08-29

Herein, a mixed metal coordination polymer, {(H 2 pip)[Zn 1/3 Fe 2/3 (pydc-2,5) 2 (H 2 O)]·2H 2 O} 1 {where H 2 pip = piperazinediium and pydc-2,5 = pyridine-2,5-dicarboxylate}, was successfully synthesized using a hydrothermal technique. To confirm the structure and phase purity of 1, single crystals of an isomorphous pure Fe compound, {(H 2 pip)[Fe(pydc-2,5) 2 (H 2 O)]·2H 2 O} 1a, were synthesized based on similar synthetic conditions. Single crystal X-ray data of 1a confirmed the one-dimensional anionic metal-organic coordination polymer hydrogen bonded with protonated piprazine (piperazinediium) and lattice water molecules. The phase purity of 1 and 1a were confirmed via powder X-ray diffraction. Compound 1 was systematically characterized using IR, TGA, SEM, and EDX elemental mapping analysis. Compound 1 was used as a single source precursor for the preparation of nano-sized ZnFe 2 O 4 via thermal decomposition. The as-obtained ZnFe 2 O 4 was fully characterized using PXRD, SEM, TEM, and EDX elemental mapping analysis. It was found that ZnFe 2 O 4 was formed in its pure form with particle size in the nano-dimension. The aqueous dispersion of nano-sized ZnFe 2 O 4 exhibits a strong emission at 402 nm upon excitation at 310 nm. This emissive property was employed for luminescence-based detection of nitroaromatic explosives in an aqueous medium through luminescence quenching for the first time. Importantly, selective detections have been observed for phenolic nitroaromatics based on differential luminescence quenching behaviour along with a detection limit of 57 ppb for 2,4,6-trinitrophenol (TNP) in water.

L-GRAAL: Lagrangian graphlet-based network aligner.

PubMed

Malod-Dognin, Noël; Pržulj, Nataša

2015-07-01

Discovering and understanding patterns in networks of protein-protein interactions (PPIs) is a central problem in systems biology. Alignments between these networks aid functional understanding as they uncover important information, such as evolutionary conserved pathways, protein complexes and functional orthologs. A few methods have been proposed for global PPI network alignments, but because of NP-completeness of underlying sub-graph isomorphism problem, producing topologically and biologically accurate alignments remains a challenge. We introduce a novel global network alignment tool, Lagrangian GRAphlet-based ALigner (L-GRAAL), which directly optimizes both the protein and the interaction functional conservations, using a novel alignment search heuristic based on integer programming and Lagrangian relaxation. We compare L-GRAAL with the state-of-the-art network aligners on the largest available PPI networks from BioGRID and observe that L-GRAAL uncovers the largest common sub-graphs between the networks, as measured by edge-correctness and symmetric sub-structures scores, which allow transferring more functional information across networks. We assess the biological quality of the protein mappings using the semantic similarity of their Gene Ontology annotations and observe that L-GRAAL best uncovers functionally conserved proteins. Furthermore, we introduce for the first time a measure of the semantic similarity of the mapped interactions and show that L-GRAAL also uncovers best functionally conserved interactions. In addition, we illustrate on the PPI networks of baker's yeast and human the ability of L-GRAAL to predict new PPIs. Finally, L-GRAAL's results are the first to show that topological information is more important than sequence information for uncovering functionally conserved interactions. L-GRAAL is coded in C++. Software is available at: http://bio-nets.doc.ic.ac.uk/L-GRAAL/. n.malod-dognin@imperial.ac.uk Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press.

Structures in color space

NASA Astrophysics Data System (ADS)

Petrov, Alexander P.

1996-09-01

Classic colorimetry and the traditionally used color space do not represent all perceived colors (for example, browns look dark yellow in colorimetric conditions of observation) so, the specific goal of this work is to suggest another concept of color and to prove that the corresponding set of colors is complete. The idea of our approach attributing color to surface patches (not to the light) immediately ties all the problems of color perception and vision geometry. The equivalence relation in the linear space of light fluxes F established by a procedure of colorimetry gives us a 3D color space H. By definition we introduce a sample (sigma) (surface patch) as a linear mapping (sigma) : L yields H, where L is a subspace of F called the illumination space. A Dedekind structure of partial order can be defined in the set of the samples: two samples (alpha) and (Beta) belong to one chromatic class if ker(alpha) equals ker(Beta) and (alpha) > (Beta) if ker(alpha) ker(Beta) . The maximal elements of this chain create the chromatic class BLACK. There can be given geometrical arguments for L to be 3D and it can be proved that in this case the minimal element of the above Dedekind structure is unique and the corresponding chromatic class is called WHITE containing the samples (omega) such that ker(omega) equals {0} L. Color is defined as mapping C: H yields H and assuming color constancy the complete set of perceived colors is proved to be isomorphic to a subset C of 3 X 3 matrices. This subset is convex, limited and symmetrical with E/2 as the center of symmetry. The problem of metrization of the color space C is discussed and a color metric related to shape, i.e., to vision geometry, is suggested.

Word learning emerges from the interaction of online referent selection and slow associative learning.

PubMed

McMurray, Bob; Horst, Jessica S; Samuelson, Larissa K

2012-10-01

Classic approaches to word learning emphasize referential ambiguity: In naming situations, a novel word could refer to many possible objects, properties, actions, and so forth. To solve this, researchers have posited constraints, and inference strategies, but assume that determining the referent of a novel word is isomorphic to learning. We present an alternative in which referent selection is an online process and independent of long-term learning. We illustrate this theoretical approach with a dynamic associative model in which referent selection emerges from real-time competition between referents and learning is associative (Hebbian). This model accounts for a range of findings including the differences in expressive and receptive vocabulary, cross-situational learning under high degrees of ambiguity, accelerating (vocabulary explosion) and decelerating (power law) learning, fast mapping by mutual exclusivity (and differences in bilinguals), improvements in familiar word recognition with development, and correlations between speed of processing and learning. Together it suggests that (a) association learning buttressed by dynamic competition can account for much of the literature; (b) familiar word recognition is subserved by the same processes that identify the referents of novel words (fast mapping); (c) online competition may allow the children to leverage information available in the task to augment performance despite slow learning; (d) in complex systems, associative learning is highly multifaceted; and (e) learning and referent selection, though logically distinct, can be subtly related. It suggests more sophisticated ways of describing the interaction between situation- and developmental-time processes and points to the need for considering such interactions as a primary determinant of development. PsycINFO Database Record (c) 2012 APA, all rights reserved.

Human Induced Pluripotent Stem Cell-Derived Cardiac Cell Sheets Expressing Genetically Encoded Voltage Indicator for Pharmacological and Arrhythmia Studies.

PubMed

Shaheen, Naim; Shiti, Assad; Huber, Irit; Shinnawi, Rami; Arbel, Gil; Gepstein, Amira; Setter, Noga; Goldfracht, Idit; Gruber, Amit; Chorna, Snizhanna V; Gepstein, Lior

2018-06-05

Fulfilling the potential of human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes for studying conduction and arrhythmogenesis requires development of multicellular models and methods for long-term repeated tissue phenotyping. We generated confluent hiPSC-derived cardiac cell sheets (hiPSC-CCSs), expressing the genetically encoded voltage indicator ArcLight. ArcLight-based optical mapping allowed generation of activation and action-potential duration (APD) maps, which were validated by mapping the same hiPSC-CCSs with the voltage-sensitive dye, Di-4-ANBDQBS. ArcLight mapping allowed long-term assessment of electrical remodeling in the hiPSC-CCSs and evaluation of drug-induced conduction slowing (carbenoxolone, lidocaine, and quinidine) and APD prolongation (quinidine and dofetilide). The latter studies also enabled step-by-step depiction of drug-induced arrhythmogenesis ("torsades de pointes in the culture dish") and its prevention by MgSO 4 and rapid pacing. Phase-mapping analysis allowed biophysical characterization of spiral waves induced in the hiPSC-CCSs and their termination by electrical cardioversion and overdrive pacing. In conclusion, ArcLight mapping of hiPSC-CCSs provides a powerful tool for drug testing and arrhythmia investigation. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

MAP3K19 Is a Novel Regulator of TGF-β Signaling That Impacts Bleomycin-Induced Lung Injury and Pulmonary Fibrosis

PubMed Central

Franz-Bacon, Karin; DiTirro, Danielle N.; Ly, Tai Wei; Bacon, Kevin B.

2016-01-01

Idiopathic pulmonary fibrosis (IPF) is a progressive, debilitating disease for which two medications, pirfenidone and nintedanib, have only recently been approved for treatment. The cytokine TGF-β has been shown to be a central mediator in the disease process. We investigated the role of a novel kinase, MAP3K19, upregulated in IPF tissue, in TGF-β-induced signal transduction and in bleomycin-induced pulmonary fibrosis. MAP3K19 has a very limited tissue expression, restricted primarily to the lungs and trachea. In pulmonary tissue, expression was predominantly localized to alveolar and interstitial macrophages, bronchial epithelial cells and type II pneumocytes of the epithelium. MAP3K19 was also found to be overexpressed in bronchoalveolar lavage macrophages from IPF patients compared to normal patients. Treatment of A549 or THP-1 cells with either MAP3K19 siRNA or a highly potent and specific inhibitor reduced phospho-Smad2 & 3 nuclear translocation following TGF-β stimulation. TGF-β-induced gene transcription was also strongly inhibited by both the MAP3K19 inhibitor and nintedanib, whereas pirfenidone had a much less pronounced effect. In combination, the MAP3K19 inhibitor appeared to act synergistically with either pirfenidone or nintedanib, at the level of target gene transcription or protein production. Finally, in an animal model of IPF, inhibition of MAP3K19 strongly attenuated bleomycin-induced pulmonary fibrosis when administered either prophylactically ortherapeutically. In summary, these results strongly suggest that inhibition of MAP3K19 may have a beneficial therapeutic effect in the treatment of IPF and represents a novel strategy to target this disease. PMID:27144281

MAP3K19 Is a Novel Regulator of TGF-β Signaling That Impacts Bleomycin-Induced Lung Injury and Pulmonary Fibrosis.

PubMed

Boehme, Stefen A; Franz-Bacon, Karin; DiTirro, Danielle N; Ly, Tai Wei; Bacon, Kevin B

2016-01-01

Idiopathic pulmonary fibrosis (IPF) is a progressive, debilitating disease for which two medications, pirfenidone and nintedanib, have only recently been approved for treatment. The cytokine TGF-β has been shown to be a central mediator in the disease process. We investigated the role of a novel kinase, MAP3K19, upregulated in IPF tissue, in TGF-β-induced signal transduction and in bleomycin-induced pulmonary fibrosis. MAP3K19 has a very limited tissue expression, restricted primarily to the lungs and trachea. In pulmonary tissue, expression was predominantly localized to alveolar and interstitial macrophages, bronchial epithelial cells and type II pneumocytes of the epithelium. MAP3K19 was also found to be overexpressed in bronchoalveolar lavage macrophages from IPF patients compared to normal patients. Treatment of A549 or THP-1 cells with either MAP3K19 siRNA or a highly potent and specific inhibitor reduced phospho-Smad2 & 3 nuclear translocation following TGF-β stimulation. TGF-β-induced gene transcription was also strongly inhibited by both the MAP3K19 inhibitor and nintedanib, whereas pirfenidone had a much less pronounced effect. In combination, the MAP3K19 inhibitor appeared to act synergistically with either pirfenidone or nintedanib, at the level of target gene transcription or protein production. Finally, in an animal model of IPF, inhibition of MAP3K19 strongly attenuated bleomycin-induced pulmonary fibrosis when administered either prophylactically ortherapeutically. In summary, these results strongly suggest that inhibition of MAP3K19 may have a beneficial therapeutic effect in the treatment of IPF and represents a novel strategy to target this disease.

In Situ D-periodic Molecular Structure of Type II Collagen

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

Antipova, Olga; Orgel, Joseph P.R.O.

Collagens are essential components of extracellular matrices in multicellular animals. Fibrillar type II collagen is the most prominent component of articular cartilage and other cartilage-like tissues such as notochord. Its in situ macromolecular and packing structures have not been fully characterized, but an understanding of these attributes may help reveal mechanisms of tissue assembly and degradation (as in osteo- and rheumatoid arthritis). In some tissues such as lamprey notochord, the collagen fibrillar organization is naturally crystalline and may be studied by x-ray diffraction. We used diffraction data from native and derivative notochord tissue samples to solve the axial, D-periodic structuremore » of type II collagen via multiple isomorphous replacement. The electron density maps and heavy atom data revealed the conformation of the nonhelical telopeptides and the overall D-periodic structure of collagen type II in native tissues, data that were further supported by structure prediction and transmission electron microscopy. These results help to explain the observed differences in collagen type I and type II fibrillar architecture and indicate the collagen type II cross-link organization, which is crucial for fibrillogenesis. Transmission electron microscopy data show the close relationship between lamprey and mammalian collagen fibrils, even though the respective larger scale tissue architecture differs.« less

Phosphorus removal characteristics in hydroxyapatite crystallization using converter slag.

PubMed

Kim, Eung-Ho; Hwang, Hwan-Kook; Yim, Soo-Bin

2006-01-01

This study was performed to investigate the phosphorus removal characteristics in hydroxyapatite (HAP) crystallization using converter slag as a seed crystal and the usefulness of a slag column reactor system. The effects of alkalinity, and the isomorphic-substitutable presence of ionic magnesium, fluoride, and iron on HAP crystallization seeded with converter slag, were examined using a batch reactor system. The phosphorus removal efficiencies of the batch reactor system were found to increase with increases in the iron and fluoride ion concentrations, and to decrease with increases in the alkalinity and magnesium ion concentration. A column reactor system for HAP crystallization using converter slag was found to achieve high, stable levels of phosphorus elimination: the average PO4-P removal efficiency over 414 days of operation was 90.4%, in which the effluent phosphorus concentration was maintained at less than 0.5 mg/L under the appropriate phosphorus crystallization conditions. The X-ray diffraction (XRD) patterns and Fourier transform infrared (FTIR) spectra of the crystalline material deposited on the seed particles exhibited peaks consistent with HAP. Scanning electron micrograph (SEM) images showed that finely distributed crystalline material was formed on the surfaces of the seed particles. Energy dispersive X-ray spectroscopy (EDS) mapping analysis revealed that the molar Ca/P composition ratio of the crystalline material was 1.72.

The N14 anti-afamin antibody Fab: a rare VL1 CDR glycosylation, crystallographic re-sequencing, molecular plasticity and conservative versus enthusiastic modelling.

PubMed

Naschberger, Andreas; Fürnrohr, Barbara G; Lenac Rovis, Tihana; Malic, Suzana; Scheffzek, Klaus; Dieplinger, Hans; Rupp, Bernhard

2016-12-01

The monoclonal antibody N14 is used as a detection antibody in ELISA kits for the human glycoprotein afamin, a member of the albumin family, which has recently gained interest in the capture and stabilization of Wnt signalling proteins, and for its role in metabolic syndrome and papillary thyroid carcinoma. As a rare occurrence, the N14 Fab is N-glycosylated at Asn26L at the onset of the V L 1 antigen-binding loop, with the α-1-6 core fucosylated complex glycan facing out of the L1 complementarity-determining region. The crystal structures of two non-apparent (pseudo) isomorphous crystals of the N14 Fab were analyzed, which differ significantly in the elbow angles, thereby cautioning against the overinterpretation of domain movements upon antigen binding. In addition, the map quality at 1.9 Å resolution was sufficient to crystallographically re-sequence the variable V L and V H domains and to detect discrepancies in the hybridoma-derived sequence. Finally, a conservatively refined parsimonious model is presented and its statistics are compared with those from a less conservatively built model that has been modelled more enthusiastically. Improvements to the PDB validation reports affecting ligands, clashscore and buried surface calculations are suggested.

PSF mapping-based correction of eddy-current-induced distortions in diffusion-weighted echo-planar imaging.

PubMed

In, Myung-Ho; Posnansky, Oleg; Speck, Oliver

2016-05-01

To accurately correct diffusion-encoding direction-dependent eddy-current-induced geometric distortions in diffusion-weighted echo-planar imaging (DW-EPI) and to minimize the calibration time at 7 Tesla (T). A point spread function (PSF) mapping based eddy-current calibration method is newly presented to determine eddy-current-induced geometric distortions even including nonlinear eddy-current effects within the readout acquisition window. To evaluate the temporal stability of eddy-current maps, calibration was performed four times within 3 months. Furthermore, spatial variations of measured eddy-current maps versus their linear superposition were investigated to enable correction in DW-EPIs with arbitrary diffusion directions without direct calibration. For comparison, an image-based eddy-current correction method was additionally applied. Finally, this method was combined with a PSF-based susceptibility-induced distortion correction approach proposed previously to correct both susceptibility and eddy-current-induced distortions in DW-EPIs. Very fast eddy-current calibration in a three-dimensional volume is possible with the proposed method. The measured eddy-current maps are very stable over time and very similar maps can be obtained by linear superposition of principal-axes eddy-current maps. High resolution in vivo brain results demonstrate that the proposed method allows more efficient eddy-current correction than the image-based method. The combination of both PSF-based approaches allows distortion-free images, which permit reliable analysis in diffusion tensor imaging applications at 7T. © 2015 Wiley Periodicals, Inc.

Heuristics in Problem Solving: The Role of Direction in Controlling Search Space

ERIC Educational Resources Information Center

Chu, Yun; Li, Zheng; Su, Yong; Pizlo, Zygmunt

2010-01-01

Isomorphs of a puzzle called m+m resulted in faster solution times and an easily reproduced solution path in a labeled version of the problem compared to a more difficult binary version. We conjecture that performance is related to a type of heuristic called direction that not only constrains search space in the labeled version, but also…

Two-dimensional Manifold with Point-like Defects

NASA Astrophysics Data System (ADS)

Gani, V. A.; Dmitriev, A. E.; Rubin, S. G.

We study a class of two-dimensional compact extra spaces isomorphic to the sphere S 2 in the framework of multidimensional gravitation. We show that there exists a family of stationary metrics that depend on the initial (boundary) conditions. All these geometries have a singular point. We also discuss the possibility for these deformed extra spaces to be considered as dark matter candidates.

The Role of Institutional Dual Embeddedness in the Strategic Local Adaptation of International Branch Campuses: Evidence from Malaysia and Singapore

ERIC Educational Resources Information Center

Shams, Farshid; Huisman, Jeroen

2016-01-01

Past research revealed that International Branch Campuses (IBCs) are simultaneously under two types of isomorphic pressures. On the one hand, they are obliged to conform to the institutions of their host countries, which lead them towards homogenising with the local Higher Education Institutions (HEIs), hence deviate from their parent unit's…

Specific Features of the Response of Cerium to Pulsed Actions

NASA Astrophysics Data System (ADS)

Atroshenko, S. A.; Zubareva, A. N.; Morozov, V. A.; Savenkov, G. G.; Utkin, A. V.

2018-02-01

Experimental studies of cerium at high rates and nanosecond durations of action have been performed. The isomorphic phase transition was studied upon shock compression. The spall strength of cerium has been determined. Cerium demonstrates anomalous compressibility upon dynamic loading. Stress waves dampen under action of a high-current electron beam due to the energy dissipation during fragmentation and twinning.

Use of Item Models in a Large-Scale Admissions Test: A Case Study

ERIC Educational Resources Information Center

Sinharay, Sandip; Johnson, Matthew S.

2008-01-01

"Item models" (LaDuca, Staples, Templeton, & Holzman, 1986) are classes from which it is possible to generate items that are equivalent/isomorphic to other items from the same model (e.g., Bejar, 1996, 2002). They have the potential to produce large numbers of high-quality items at reduced cost. This article introduces data from an…

Classification of real Lie superalgebras based on a simple Lie algebra, giving rise to interesting examples involving {mathfrak {su}}(2,2)

NASA Astrophysics Data System (ADS)

Guzzo, H.; Hernández, I.; Sánchez-Valenzuela, O. A.

2014-09-01

Finite dimensional semisimple real Lie superalgebras are described via finite dimensional semisimple complex Lie superalgebras. As an application of these results, finite dimensional real Lie superalgebras mathfrak {m}=mathfrak {m}_0 oplus mathfrak {m}_1 for which mathfrak {m}_0 is a simple Lie algebra are classified up to isomorphism.

A Meta-Analysis of Institutional Theories

DTIC Science & Technology

1989-06-01

GPOUP SUBGROUP Institutional Theory , Isomorphism, Administrative Difterpntiation, Diffusion of Change, Rational, Unit Of Analysis 19 ABSTRACT (Continue on... institutional theory may lead to better decision making and evaluation criteria on the part of managers in the non-profit sector. C. SCOPE This paper... institutional theory : I) Organizations evolving in environments with elabora- ted institutional rules create structure that conform to those rules. 2

Algorithms for computations of Loday algebras' invariants

NASA Astrophysics Data System (ADS)

Hussain, Sharifah Kartini Said; Rakhimov, I. S.; Basri, W.

2017-04-01

The paper is devoted to applications of some computer programs to study structural determination of Loday algebras. We present how these computer programs can be applied in computations of various invariants of Loday algebras and provide several computer programs in Maple to verify Loday algebras' identities, the isomorphisms between the algebras, as a special case, to describe the automorphism groups, centroids and derivations.

Entrepreneurial organizations: the driving force for improving quality in the healthcare industry.

PubMed

Borkowski, Nancy; Gordon, Jean

2006-01-01

Using DiMaggio and Powell's concept of institutional isomorphism, the authors explain why healthcare lags behind other industries in innovating new production functions that address quality. Healthcare finns can "learn" to be entrepreneurial organizations within Stevenson's 'entrepreneurial versus administrative behavior' framework and Covin and Slevin's model of an entrepreneurial organization's required culture and behavioral support structure.

Trace of the Twisted Heisenberg Category

NASA Astrophysics Data System (ADS)

Oğuz, Can Ozan; Reeks, Michael

2017-12-01

We show that the trace decategorification, or zeroth Hochschild homology, of the twisted Heisenberg category defined by Cautis and Sussan is isomorphic to a quotient of {W^-}, a subalgebra of W_{1+∞} defined by Kac, Wang, and Yan. Our result is a twisted analogue of that by Cautis, Lauda, Licata, and Sussan relating W_{1+∞} and the trace decategorification of the Heisenberg category.

Avoiding the "Inexorable Push toward Homogenization" in School Choice: Education Savings Accounts as Hedges against Institutional Isomorphism

ERIC Educational Resources Information Center

Burke, Lindsey M.

2016-01-01

The assumption that rational choice dynamics will lead to diversity of school supply is at the heart of K-12 school choice arrangements. Yet as the field of school choice becomes more established, there will be the "inexorable push toward homogenization." If vouchers, tuition tax credit scholarships, and education savings accounts become…

The Diagnostic Drawing Series and the Tree Rating Scale: An Isomorphic Representation of Multiple Personality Disorder, Major Depression, and Schizophrenic Populations.

ERIC Educational Resources Information Center

Morris, Maureen Batza

1995-01-01

The tree drawings of 80 subjects, who were diagnosed with either multiple personality disorder, schizophrenia, or major depression, and a control group, were rated. Patterns were examined and graphs were used to depict results. Certain features were found to distinguish each category. The descriptive statistical findings were both consistent and…

On the equivalence of some spectral sequences for Serre fibrations

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

Onishchenko, Aleksandr Yu; Popelenskii, Fedor Yu

2011-04-30

Several different constructions of a spectral sequence for a Serre fibration {pi}:E{yields}B over a compact simply connected manifold B are considered in this paper. Namely, we consider the spectral sequence for the minimal model ({Lambda}Vx{Lambda}W,d) of the fibration, along with the spectral sequences arising from the Cech filtration in the complexes C*(U,A*{sub PL}({pi}{sup -1}(U))) and C*(U,S*({pi}{sup -1}(U))), where U=(U) is a covering of the base B. It is known that all these spectral sequences have the same terms E{sub 2}*{sup ,}*=H*(X)xH{sup *}(F) and converge to the cohomology of the total space E. A new natural isomorphism of these spectral sequencesmore » is constructed in every term E{sub r} with r{>=}2. It is also proved that in the case of a smooth locally trivial fibration these spectral sequences are isomorphic to the spectral sequences of the complex of smooth forms {Omega}*(E) and of the Cech-de Rham complex. It is therefore established that all these constructions give the same spectral sequence, starting from the E{sub 2} term. Bibliography: 9 titles.« less

Pattern formations and optimal packing.

PubMed

Mityushev, Vladimir

2016-04-01

Patterns of different symmetries may arise after solution to reaction-diffusion equations. Hexagonal arrays, layers and their perturbations are observed in different models after numerical solution to the corresponding initial-boundary value problems. We demonstrate an intimate connection between pattern formations and optimal random packing on the plane. The main study is based on the following two points. First, the diffusive flux in reaction-diffusion systems is approximated by piecewise linear functions in the framework of structural approximations. This leads to a discrete network approximation of the considered continuous problem. Second, the discrete energy minimization yields optimal random packing of the domains (disks) in the representative cell. Therefore, the general problem of pattern formations based on the reaction-diffusion equations is reduced to the geometric problem of random packing. It is demonstrated that all random packings can be divided onto classes associated with classes of isomorphic graphs obtained from the Delaunay triangulation. The unique optimal solution is constructed in each class of the random packings. If the number of disks per representative cell is finite, the number of classes of isomorphic graphs, hence, the number of optimal packings is also finite. Copyright © 2016 Elsevier Inc. All rights reserved.

On the equivalence of some spectral sequences for Serre fibrations

NASA Astrophysics Data System (ADS)

Onishchenko, Aleksandr Yu; Popelenskii, Fedor Yu

2011-04-01

Several different constructions of a spectral sequence for a Serre fibration \\pi\\colon E \\to B over a compact simply connected manifold B are considered in this paper. Namely, we consider the spectral sequence for the minimal model (\\Lambda V\\otimes \\Lambda W,d) of the fibration, along with the spectral sequences arising from the Čech filtration in the complexes \\check{C}^*(\\mathscr{U}, A_{PL}^*(\\pi^{-1}(U))) and \\check{C}^*(\\mathscr{U}, S^*(\\pi^{-1}(U))), where \\mathscr{U}=\\{U\\} is a covering of the base B. It is known that all these spectral sequences have the same terms E_2^{*,*}=H^*(X)\\otimes H^*(F) and converge to the cohomology of the total space E. A new natural isomorphism of these spectral sequences is constructed in every term E_r with r\\ge2. It is also proved that in the case of a smooth locally trivial fibration these spectral sequences are isomorphic to the spectral sequences of the complex of smooth forms \\Omega^*(E) and of the Čech-de Rham complex. It is therefore established that all these constructions give the same spectral sequence, starting from the E_2 term. Bibliography: 9 titles.

A Variant of the Mukai Pairing via Deformation Quantization

NASA Astrophysics Data System (ADS)

Ramadoss, Ajay C.

2012-06-01

Let X be a smooth projective complex variety. The Hochschild homology HH•( X) of X is an important invariant of X, which is isomorphic to the Hodge cohomology of X via the Hochschild-Kostant-Rosenberg isomorphism. On HH•( X), one has the Mukai pairing constructed by Caldararu. An explicit formula for the Mukai pairing at the level of Hodge cohomology was proven by the author in an earlier work (following ideas of Markarian). This formula implies a similar explicit formula for a closely related variant of the Mukai pairing on HH•( X). The latter pairing on HH•( X) is intimately linked to the study of Fourier-Mukai transforms of complex projective varieties. We give a new method to prove a formula computing the aforementioned variant of Caldararu's Mukai pairing. Our method is based on some important results in the area of deformation quantization. In particular, we use part of the work of Kashiwara and Schapira on Deformation Quantization modules together with an algebraic index theorem of Bressler, Nest and Tsygan. Our new method explicitly shows that the "Noncommutative Riemann-Roch" implies the classical Riemann-Roch. Further, it is hoped that our method would be useful for generalization to settings involving certain singular varieties.

Fabrication of SrTiO3 nanotubes via an isomorphic conversion strategy

NASA Astrophysics Data System (ADS)

Yang, Dong; Zou, Xiaoyan; Tong, Zhenwei; Nan, Yanhu; Ding, Fei; Jiang, Zhongyi

2018-02-01

One-dimensional nanotubes have attracted enormous attention due to their specific structure and excellent performance since the carbon nanotube was prepared. In this study, the open-ended SrTiO3 nanotubes (STNTs) have been fabricated for the first time via an isomorphic conversion strategy using the protonated titanate nanotubes (HTNTs) as the precursor and template under the hydrothermal treatment. The as-prepared STNTs consist of uniform and continuous multilayers, having inner and outer diameters about 8.0 and 13 nm. The STNT formation involves the exchange of Sr2+ ions with H+ ions in HTNTs and then in situ growth of cubic SrTiO3 crystals by the templating of HTNT frameworks. It is found that the diffusion process of Sr2+ ions plays a critical role in controlling the nanotube morphology of SrTiO3 crystals. In addition, the SrTiO3 nanotubes exhibit high photocatalytic activity for the Cr(VI) reduction, which can reduce nearly 100% Cr(VI) within 6 h under simulated sunlight irradiation. The current strategy may be broadly applicable for fabricating the nanotubes from raw materials without 2D layered nanostructure. [Figure not available: see fulltext.

Comparing Algorithms for Graph Isomorphism Using Discrete- and Continuous-Time Quantum Random Walks

DOE PAGES

Rudinger, Kenneth; Gamble, John King; Bach, Eric; ...

2013-07-01

Berry and Wang [Phys. Rev. A 83, 042317 (2011)] show numerically that a discrete-time quan- tum random walk of two noninteracting particles is able to distinguish some non-isomorphic strongly regular graphs from the same family. Here we analytically demonstrate how it is possible for these walks to distinguish such graphs, while continuous-time quantum walks of two noninteracting parti- cles cannot. We show analytically and numerically that even single-particle discrete-time quantum random walks can distinguish some strongly regular graphs, though not as many as two-particle noninteracting discrete-time walks. Additionally, we demonstrate how, given the same quantum random walk, subtle di erencesmore » in the graph certi cate construction algorithm can nontrivially im- pact the walk's distinguishing power. We also show that no continuous-time walk of a xed number of particles can distinguish all strongly regular graphs when used in conjunction with any of the graph certi cates we consider. We extend this constraint to discrete-time walks of xed numbers of noninteracting particles for one kind of graph certi cate; it remains an open question as to whether or not this constraint applies to the other graph certi cates we consider.« less

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

Costigliola, Lorenzo; Schrøder, Thomas B.; Dyre, Jeppe C.

The recent theoretical prediction by Maimbourg and Kurchan [e-print http://arxiv.org/abs/1603.05023 (2016)] that for regular pair-potential systems the virial potential-energy correlation coefficient increases towards unity as the dimension d goes to infinity is investigated for the standard 12-6 Lennard-Jones fluid. This is done by computer simulations for d = 2, 3, 4 going from the critical point along the critical isotherm/isochore to higher density/temperature. In both cases the virial potential-energy correlation coefficient increases significantly. For a given density and temperature relative to the critical point, with increasing number of dimension the Lennard-Jones system conforms better to the hidden-scale-invariance property characterized bymore » high virial potential-energy correlations (a property that leads to the existence of isomorphs in the thermodynamic phase diagram, implying that it becomes effectively one-dimensional in regard to structure and dynamics). The present paper also gives the first numerical demonstration of isomorph invariance of structure and dynamics in four dimensions. Our findings emphasize the need for a universally applicable 1/d expansion in liquid-state theory; we conjecture that the systems known to obey hidden scale invariance in three dimensions are those for which the yet-to-be-developed 1/d expansion converges rapidly.« less

Clifford coherent state transforms on spheres

NASA Astrophysics Data System (ADS)

Dang, Pei; Mourão, José; Nunes, João P.; Qian, Tao

2018-01-01

We introduce a one-parameter family of transforms, U(m)t , t > 0, from the Hilbert space of Clifford algebra valued square integrable functions on the m-dimensional sphere, L2(Sm , dσm) ⊗Cm+1, to the Hilbert spaces, ML2(R m + 1 ∖ { 0 } , dμt) , of solutions of the Euclidean Dirac equation on R m + 1 ∖ { 0 } which are square integrable with respect to appropriate measures, dμt. We prove that these transforms are unitary isomorphisms of the Hilbert spaces and are extensions of the Segal-Bargman coherent state transform, U(1) :L2(S1 , dσ1) ⟶ HL2(C ∖ { 0 } , dμ) , to higher dimensional spheres in the context of Clifford analysis. In Clifford analysis it is natural to replace the analytic continuation from Sm to SCm as in (Hall, 1994; Stenzel, 1999; Hall and Mitchell, 2002) by the Cauchy-Kowalewski extension from Sm to R m + 1 ∖ { 0 } . One then obtains a unitary isomorphism from an L2-Hilbert space to a Hilbert space of solutions of the Dirac equation, that is to a Hilbert space of monogenic functions.

Noncommutative Differential Geometry of Generalized Weyl Algebras

NASA Astrophysics Data System (ADS)

Brzeziński, Tomasz

2016-06-01

Elements of noncommutative differential geometry of Z-graded generalized Weyl algebras A(p;q) over the ring of polynomials in two variables and their zero-degree subalgebras B(p;q), which themselves are generalized Weyl algebras over the ring of polynomials in one variable, are discussed. In particular, three classes of skew derivations of A(p;q) are constructed, and three-dimensional first-order differential calculi induced by these derivations are described. The associated integrals are computed and it is shown that the dimension of the integral space coincides with the order of the defining polynomial p(z). It is proven that the restriction of these first-order differential calculi to the calculi on B(p;q) is isomorphic to the direct sum of degree 2 and degree -2 components of A(p;q). A Dirac operator for B(p;q) is constructed from a (strong) connection with respect to this differential calculus on the (free) spinor bimodule defined as the direct sum of degree 1 and degree -1 components of A(p;q). The real structure of KO-dimension two for this Dirac operator is also described.

Comparison of carbon dioxide, argon, and nitrogen for inducing unconsciousness or euthanasia of rats.

PubMed

Sharp, Jody; Azar, Toni; Lawson, David

2006-03-01

We compared CO(2), Ar, and N(2) for inducing unconsciousness and euthanasia of Sprague-Dawley rats. We determined time to unconsciousness and monitored heart rate (HR) and mean arterial blood pressure (MAP) by radiotelemetry to assess stress, recovery after exposure, and time of death. Unconsciousness (mean +/- standard error) occurred 24 +/- 3, 87 +/- 8, and 93 +/- 8 s after short-term exposure to CO(2), Ar, and N(2), respectively. During exposure, CO(2) depressed HR, whereas Ar and N(2) increased HR. Upon removal from the chamber, rats' HR rapidly normalized after CO(2) or N(2) but remained elevated for 60 min after Ar. During exposure, all agents depressed MAP, which returned to resting levels 10 to 50 min after rats' removal from the chamber. For euthanasia, CO(2) at approximately 100% induced unconsciousness in 37 +/- 3 s, increased and then depressed MAP and HR, and caused death at 188 +/- 15 s. CO(2) at approximately 30% induced unconsciousness in 150 +/- 15 s, decreased HR and MAP, and induced death at 440 +/- 9 s. Ar at approximately 100% increased MAP but decreased HR, induced unconsciousness with hyperreflexia at 54 +/- 4 s, and caused death at 197 +/- 20 s. N(2) at approximately 100% decreased MAP but not HR and produced unconsciousness with hyperreflexia at 164 +/- 17 s and death at 426 +/- 28 s. We conclude that CO(2) effectively produced unconsciousness and euthanasia, but we were unable to ascertain distress. Ar also appears effective but produced hyperreflexia and tachycardia. N(2) was ineffective.

Mitogen-activated protein kinase inhibitors suppress prostaglandin F(2alpha)-induced myosin-light chain phosphorylation and contraction in iris sphincter smooth muscle.

PubMed

Yousufzai, S Y; Gao, G; Abdel-Latif, A A

2000-10-27

The purpose of this study was to investigate the potential role of mitogen-activated protein (MAP) kinase in contraction by monitoring MAP kinase phosphorylation (activation) and contraction during agonist stimulation of cat iris sphincter smooth muscle. Changes in tension in response to prostaglandin F(2alpha), latanoprost, a prostaglandin F(2alpha) analog used as an anti-glaucoma drug, and carbachol were recorded isometrically, and MAP kinase activation was monitored by Western blot using a phosphospecific p42/p44 MAP kinase antibody. We found that treatment of the muscle with 2'-Amino-3'-methoxyflavone (PD98059) (10 microM), a specific inhibitor of MAP kinase kinase (MEK), inhibited significantly prostaglandin F(2alpha)- and latanoprost-induced phosphorylation and contraction, but had little effect on those evoked by carbachol. Prostaglandin F(2alpha) increased MAP kinase phosphorylation in a concentration-dependent manner with EC(50) value of 1.1 x 10(-8) M and increased contraction with EC(50) of 0.92 x 10(-9) M. The MAP kinase inhibitors PD98059, Apigenin and 1,4-Diamino-2,3-dicyano-1, 4bis(2-aminophenylthio)butadiene (UO126) inhibited prostaglandin F(2alpha)-induced contraction in a concentration-dependent manner with IC(50) values of 2.4, 3.0 and 4.8 microM, respectively. PD98059 had no effect on prostaglandin F(2alpha)- or on carbachol-stimulated inositol-1,4,5-trisphosphate (IP(3)) production. In contrast, the MAP kinase inhibitor inhibited prostaglandin F(2alpha)-induced myosin-light chain (MLC) phosphorylation, but had no effect on that of carbachol. N-[2-(N-(4-Chloro-cinnamyl)-N-methylaminomethyl)phenyl]-N-[2- hydroxyethyl]-4-methoxybenzenesulfonamide (KN-93) (10 microM), a Ca(2+)-calmodulin-dependent protein kinase inhibitor, and Wortmannin (10 microM), an MLC kinase inhibitor, inhibited significantly (by 80%) prostaglandin F(2alpha)- and carbachol-induced contraction. It can be concluded that in this smooth muscle p42/p44 MAP kinases are involved in the mechanism of prostaglandin F(2alpha)-, but not in that of carbachol, induced contraction. In addition, these data clearly indicate that the stimulation of the iris sphincter with prostaglandin F(2alpha) and carbachol activate two distinct pathways, the MAP kinase pathway and the Ca(2+) mobilization pathway.

Lubin-Tate extensions, an elementary approach

NASA Astrophysics Data System (ADS)

Ershov, Yu L.

2007-12-01

We give an elementary proof of the assertion that the Lubin-Tate extension L\\ge K is an Abelian extension whose Galois group is isomorphic to U_K/N_{L/K}(U_L) for arbitrary fields K that have Henselian discrete valuation rings with finite residue fields. The term `elementary' only means that the proofs are algebraic (that is, no transcedental methods are used [1], pp. 327, 332).

Isopermutation group

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

Muktibodh, A. S.

2015-03-10

The concept of ‘Isotopy’ as formulated by Ruggero Maria Santilli [1, 2, 3] plays a vital role in the development of Iso mathematics. Santilli defined iso-fields of characteristic zero. In this paper we extend this definition to define Iso-Galois fields [4] which are essentially of non-zero characteristic. Isotopically isomorphic realizations of a group define isopermutation group which gives a clear cut distinction between automorphic groups and isotopic groups.

Association Rule Based Feature Extraction for Character Recognition

NASA Astrophysics Data System (ADS)

Dua, Sumeet; Singh, Harpreet

Association rules that represent isomorphisms among data have gained importance in exploratory data analysis because they can find inherent, implicit, and interesting relationships among data. They are also commonly used in data mining to extract the conditions among attribute values that occur together frequently in a dataset [1]. These rules have wide range of applications, namely in the financial and retail sectors of marketing, sales, and medicine.

On Graph Isomorphism and the PageRank Algorithm

DTIC Science & Technology

2008-09-01

specifies the probability of visiting each node from any other node. The perturbed matrix satisfies the Perron - Frobenius theorem’s conditions. Therefore... Frobenius and Perron theorems establishes the matrix must yield the dominant eigenvalue, one. Normalizing the unique and associated dominant eigenvector...is constructed such that none of its entries equal zero. An arbitrary PageRank matrix, S, is irreducible and satisfies the Perron - Frobenius

Such stuff as NREM dreams are made on?

PubMed

Cicogna, PierCarla; Occhionero, Miranda

2013-12-01

The question that we deal with in this commentary is the need to clarify the synergistic role of different non-rapid eye movement (NREM) sleep stages (stages 2 and 3-4) with REM and while awake in elaborative encoding of episodic memory. If the assumption is that there is isomorphism between neuronal and cognitive networks, then more detailed analysis of NREM sleep and dreams is absolutely necessary.

German and Ukrainian Phonological Isomorphs. Typology: Germanic and Slavic Languages. German-Ukraine-Slavic Contrasting Correspondence Vocabulary

ERIC Educational Resources Information Center

Petryshyn, Ivan

2016-01-01

The works of many scholars on Germanic and Slavic Languages do not really try to contrast the two biggest Indo-European language families, but analyse them seperately, as any close comparison seem to be unconvincible. In many works, we find some parts that usually would deal with loan words/borrowings/barbarisms. And, yet, we noticed that there…

Exchange interactions and magnetic properties of hexagonal rare-earth-cobalt compounds

NASA Astrophysics Data System (ADS)

Burzo, E.

2018-03-01

The magnetic properties of some GdxY1-xCo4A compounds with A = Co, Si or B are analysed including the pressure effects. Isomorphous structure transitions, parallelly with changes of cobalt moments from high spin states to low spin states, were shown as pressure increases. The magnetic data, obtained from band structures, were compared with those predicted by the mean field model.

Dreaming is not controlled by hippocampal mechanisms.

PubMed

Solms, Mark

2013-12-01

Links with the Humanities are to be welcomed, but they cannot be exempted from normal scientific criteria. Any hypothesis regarding the function of dreams that is premised on rapid eye movement (REM)/dream isomorphism is unsupportable on empirical grounds. Llewellyn's hypothesis has the further problem of counter-evidence in respect of its claim that dreaming relies upon hippocampal functions. The hypothesis also lacks face validity.

Why were Matrix Mechanics and Wave Mechanics considered equivalent?

NASA Astrophysics Data System (ADS)

Perovic, Slobodan

A recent rethinking of the early history of Quantum Mechanics deemed the late 1920s agreement on the equivalence of Matrix Mechanics and Wave Mechanics, prompted by Schrödinger's 1926 proof, a myth. Schrödinger supposedly failed to prove isomorphism, or even a weaker equivalence ("Schrödinger-equivalence") of the mathematical structures of the two theories; developments in the early 1930s, especially the work of mathematician von Neumann provided sound proof of mathematical equivalence. The alleged agreement about the Copenhagen Interpretation, predicated to a large extent on this equivalence, was deemed a myth as well. In response, I argue that Schrödinger's proof concerned primarily a domain-specific ontological equivalence, rather than the isomorphism or a weaker mathematical equivalence. It stemmed initially from the agreement of the eigenvalues of Wave Mechanics and energy-states of Bohr's Model that was discovered and published by Schrödinger in his first and second communications of 1926. Schrödinger demonstrated in this proof that the laws of motion arrived at by the method of Matrix Mechanics are satisfied by assigning the auxiliary role to eigenfunctions in the derivation of matrices (while he only outlined the reversed derivation of eigenfunctions from Matrix Mechanics, which was necessary for the proof of both isomorphism and Schrödinger-equivalence of the two theories). This result was intended to demonstrate the domain-specific ontological equivalence of Matrix Mechanics and Wave Mechanics, with respect to the domain of Bohr's atom. And although the mathematical equivalence of the theories did not seem out of the reach of existing theories and methods, Schrödinger never intended to fully explore such a possibility in his proof paper. In a further development of Quantum Mechanics, Bohr's complementarity and Copenhagen Interpretation captured a more substantial convergence of the subsequently revised (in light of the experimental results) Wave and Matrix Mechanics. I argue that both the equivalence and Copenhagen Interpretation can be deemed myths if one predicates the philosophical and historical analysis on a narrow model of physical theory which disregards its historical context, and focuses exclusively on its formal aspects and the exploration of the logical models supposedly implicit in it.

On Parametrization of the Linear GL(4,C) and Unitary SU(4) Groups in Terms of Dirac Matrices

NASA Astrophysics Data System (ADS)

Red'Kov, Victor M.; Bogush, Andrei A.; Tokarevskaya, Natalia G.

2008-02-01

Parametrization of 4 × 4-matrices G of the complex linear group GL(4,C) in terms of four complex 4-vector parameters (k,m,n,l) is investigated. Additional restrictions separating some subgroups of GL(4,C) are given explicitly. In the given parametrization, the problem of inverting any 4 × 4 matrix G is solved. Expression for determinant of any matrix G is found: det G = F(k,m,n,l). Unitarity conditions G+ = G-1 have been formulated in the form of non-linear cubic algebraic equations including complex conjugation. Several simplest solutions of these unitarity equations have been found: three 2-parametric subgroups G1, G2, G3 - each of subgroups consists of two commuting Abelian unitary groups; 4-parametric unitary subgroup consis! ting of a product of a 3-parametric group isomorphic SU(2) and 1-parametric Abelian group. The Dirac basis of generators Λk, being of Gell-Mann type, substantially differs from the basis λi used in the literature on SU(4) group, formulas relating them are found - they permit to separate SU(3) subgroup in SU(4). Special way to list 15 Dirac generators of GL(4,C) can be used {Λk} = {μiÅνjÅ(μiVνj = KÅL ÅM )}, which permit to factorize SU(4) transformations according to S = eiaμ eibνeikKeilLeimM, where two first factors commute with each other and are isomorphic to SU(2) group, the three last ones are 3-parametric groups, each of them consisting of three Abelian commuting unitary subgroups. Besides, the structure of fifteen Dirac matrices Λk permits to separate twenty 3-parametric subgroups in SU(4) isomorphic to SU(2); those subgroups might be used as bigger elementary blocks in constructing of a general transformation SU(4). It is shown how one can specify the present approach for the pseudounitary group SU(2,2) and SU(3,1).

Immune response induced by Epstein-Barr virus and Mycobacterium avium subsp. paratuberculosis peptides in current and past infectious mononucleosis: a risk for multiple sclerosis?

PubMed

Mameli, G; Madeddu, G; Cossu, D; Galleri, G; Manetti, R; Babudieri, S; Mura, M Stella; Sechi, L A

2016-01-01

Infectious mononucleosis (IM) caused by Epstein-Barr virus (EBV) has been associated with increased risk of multiple sclerosis (MS). However, the mechanism linking these pathologies is unclear. Different reports indicate the association of EBV, and recently Mycobacterium avium subsp. paratuberculosis (MAP), with MS. For a better understanding of the role of these pathogens, the host response induced by selected antigenic peptides in subjects with a history of IM that significantly increases the risk of MS was investigated. Both humoral and cell-mediated response against peptides able to induce a specific immune activation in MS patients deriving from lytic and latent EBV antigens BOLF1(305-320), EBNA1(400-413), from MAP MAP_4027(18-32), MAP_0106c(121-132) and from human proteins IRF5(424-434) and MBP(85-98) in subjects with current and past IM were examined. EBNA1 and MAP_0106c peptides were able to induce a humoral immune response in subjects with a history of clinical IM in an independent manner. Moreover, these peptides were capable of inducing pro-inflammatory cytokine interferon γ by CD4+ and CD8+ T lymphocytes and interleukin 6 and tumour necrosis factor α by CD14+ monocyte cells. Our results highlight that EBV and MAP may be involved independently in the same causal process leading to MS in subjects with a history of IM. © 2015 EAN.

Changes in arterial blood pressure elicited by severe passive heating at rest is associated with hyperthermia-induced hyperventilation in humans.

PubMed

Fujii, Naoto; Ichinose, Masashi; Honda, Yasushi; Tsuji, Bun; Watanabe, Kazuhito; Kondo, Narihiko; Nishiyasu, Takeshi

2013-01-01

The arterial blood pressure and ventilatory responses to severe passive heating at rest varies greatly among individuals. We tested the hypothesis that the increase in ventilation seen during severe passive heating of resting humans is associated with a decrease in arterial blood pressure. Passive heating was performed on 18 healthy males using hot water immersion to the level of the iliac crest and a water-perfused suit. We then divided the subjects into two groups: MAP(NOTINC) (n = 8), whose mean arterial blood pressure (MAP) at the end of heating had increased by ≤3 mmHg, and MAP(INC) (n = 10), whose MAP increased by >3 mmHg. Increases in esophageal temperature (T (es)) elicited by the heating were similar in the two groups (+2.3 ± 0.3 vs. +2.4 ± 0.4 °C). Early during heating (increase in T (es) was <1.5 °C), MAP, minute ventilation ([Formula: see text]), and end-tidal CO(2) pressure ([Formula: see text]) were similar between the groups. However, during the latter part of heating (increase in T (es) was ≥1.5 °C), the increase in [Formula: see text] and decrease in [Formula: see text] were significantly greater or tended to be greater, while the increase in MAP was significantly smaller in MAP(NOTINC) than MAP(INC). Among all subjects, heating-induced changes in [Formula: see text] significantly and negatively correlated with heating-induced changes in MAP during the latter part of heating (r = -0.52 to -0.74, P < 0.05). These results suggest that, in resting humans, 25-50 % of the variation in the magnitude of the arterial blood pressure response to severe passive heating can be explained by the magnitude of hyperthermia-induced hyperventilation.

MAP3K8 (TPL2/COT) affects obesity-induced adipose tissue inflammation without systemic effects in humans and in mice.

PubMed

Ballak, Dov B; van Essen, Peter; van Diepen, Janna A; Jansen, Henry; Hijmans, Anneke; Matsuguchi, Tetsuya; Sparrer, Helmut; Tack, Cees J; Netea, Mihai G; Joosten, Leo A B; Stienstra, Rinke

2014-01-01

Chronic low-grade inflammation in adipose tissue often accompanies obesity, leading to insulin resistance and increasing the risk for metabolic diseases. MAP3K8 (TPL2/COT) is an important signal transductor and activator of pro-inflammatory pathways that has been linked to obesity-induced adipose tissue inflammation. We used human adipose tissue biopsies to study the relationship of MAP3K8 expression with markers of obesity and expression of pro-inflammatory cytokines (IL-1β, IL-6 and IL-8). Moreover, we evaluated obesity-induced adipose tissue inflammation and insulin resistance in mice lacking MAP3K8 and WT mice on a high-fat diet (HFD) for 16 weeks. Individuals with a BMI >30 displayed a higher mRNA expression of MAP3K8 in adipose tissue compared to individuals with a normal BMI. Additionally, high mRNA expression levels of IL-1β, IL-6 and IL-8, but not TNF -α, in human adipose tissue were associated with higher expression of MAP3K8. Moreover, high plasma SAA and CRP did not associate with increased MAP3K8 expression in adipose tissue. Similarly, no association was found for MAP3K8 expression with plasma insulin or glucose levels. Mice lacking MAP3K8 had similar bodyweight gain as WT mice, yet displayed lower mRNA expression levels of IL-1β, IL-6 and CXCL1 in adipose tissue in response to the HFD as compared to WT animals. However, MAP3K8 deficient mice were not protected against HFD-induced adipose tissue macrophage infiltration or the development of insulin resistance. Together, the data in both human and mouse show that MAP3K8 is involved in local adipose tissue inflammation, specifically for IL-1β and its responsive cytokines IL-6 and IL-8, but does not seem to have systemic effects on insulin resistance.

Fluoride Induces a Volume Reduction in CA1 Hippocampal Slices Via MAP Kinase Pathway Through Volume Regulated Anion Channels

PubMed Central

Lee, Jaekwang; Han, Young-Eun; Favorov, Oleg; Tommerdahl, Mark; Whitsel, Barry

2016-01-01

Regulation of cell volume is an important aspect of cellular homeostasis during neural activity. This volume regulation is thought to be mediated by activation of specific transporters, aquaporin, and volume regulated anion channels (VRAC). In cultured astrocytes, it was reported that swelling-induced mitogen-activated protein (MAP) kinase activation is required to open VRAC, which are thought to be important in regulatory volume decrease and in the response of CNS to trauma and excitotoxicity. It has been also described that sodium fluoride (NaF), a recognized G-protein activator and protein phosphatase inhibitor, leads to a significant MAP kinase activation in endothelial cells. However, NaF's effect in volume regulation in the brain is not known yet. Here, we investigated the mechanism of NaF-induced volume change in rat and mouse hippocampal slices using intrinsic optical signal (IOS) recording, in which we measured relative changes in intracellular and extracellular volume as changes in light transmittance through brain slices. We found that NaF (1~5 mM) application induced a reduction in light transmittance (decreased volume) in CA1 hippocampus, which was completely reversed by MAP kinase inhibitor U0126 (10 µM). We also observed that NaF-induced volume reduction was blocked by anion channel blockers, suggesting that NaF-induced volume reduction could be mediated by VRAC. Overall, our results propose a novel molecular mechanism of NaF-induced volume reduction via MAP kinase signaling pathway by activation of VRAC. PMID:27122993

Development of Probabilistic Flood Inundation Mapping For Flooding Induced by Dam Failure

NASA Astrophysics Data System (ADS)

Tsai, C.; Yeh, J. J. J.

2017-12-01

A primary function of flood inundation mapping is to forecast flood hazards and assess potential losses. However, uncertainties limit the reliability of inundation hazard assessments. Major sources of uncertainty should be taken into consideration by an optimal flood management strategy. This study focuses on the 20km reach downstream of the Shihmen Reservoir in Taiwan. A dam failure induced flood herein provides the upstream boundary conditions of flood routing. The two major sources of uncertainty that are considered in the hydraulic model and the flood inundation mapping herein are uncertainties in the dam break model and uncertainty of the roughness coefficient. The perturbance moment method is applied to a dam break model and the hydro system model to develop probabilistic flood inundation mapping. Various numbers of uncertain variables can be considered in these models and the variability of outputs can be quantified. The probabilistic flood inundation mapping for dam break induced floods can be developed with consideration of the variability of output using a commonly used HEC-RAS model. Different probabilistic flood inundation mappings are discussed and compared. Probabilistic flood inundation mappings are hoped to provide new physical insights in support of the evaluation of concerning reservoir flooded areas.

A role for Pyk2 and Src in linking G-protein-coupled receptors with MAP kinase activation.

PubMed

Dikic, I; Tokiwa, G; Lev, S; Courtneidge, S A; Schlessinger, J

1996-10-10

The mechanisms by which mitogenic G-protein-coupled receptors activate the MAP kinase signalling pathway are poorly understood. Candidate protein tyrosine kinases that link G-protein-coupled receptors with MAP kinase include Src family kinases, the epidermal growth factor receptor, Lyn and Syk. Here we show that lysophosphatidic acid (LPA) and bradykinin induce tyrosine phosphorylation of Pyk2 and complex formation between Pyk2 and activated Src. Moreover, tyrosine phosphorylation of Pyk2 leads to binding of the SH2 domain of Src to tyrosine 402 of Pyk2 and activation of Src. Transient overexpression of a dominant interfering mutant of Pyk2 or the protein tyrosine kinase Csk reduces LPA- or bradykinin-induced activation of MAP kinase. LPA- or bradykinin-induced MAP kinase activation was also inhibited by overexpression of dominant interfering mutants of Grb2 and Sos. We propose that Pyk2 acts with Src to link Gi- and Gq-coupled receptors with Grb2 and Sos to activate the MAP kinase signalling pathway in PC12 cells.

Vaccination with M2e-Based Multiple Antigenic Peptides: Characterization of the B Cell Response and Protection Efficacy in Inbred and Outbred Mice

PubMed Central

Wolf, Amaya I.; Mozdzanowska, Krystyna; Williams, Katie L.; Singer, David; Richter, Monique; Hoffmann, Ralf; Caton, Andrew J.; Otvos, Laszlo; Erikson, Jan

2011-01-01

Background The extracellular domain of the influenza A virus protein matrix protein 2 (M2e) is remarkably conserved between various human isolates and thus is a viable target antigen for a universal influenza vaccine. With the goal of inducing protection in multiple mouse haplotypes, M2e-based multiple antigenic peptides (M2e-MAP) were synthesized to contain promiscuous T helper determinants from the Plasmodium falciparum circumsporozoite protein, the hepatitis B virus antigen and the influenza virus hemagglutinin. Here, we investigated the nature of the M2e-MAP-induced B cell response in terms of the distribution of antibody (Ab) secreting cells (ASCs) and Ab isotypes, and tested the protective efficacy in various mouse strains. Methodology/Principal Findings Immunization of BALB/c mice with M2e-MAPs together with potent adjuvants, CpG 1826 oligonucleotides (ODN) and cholera toxin (CT) elicited high M2e-specific serum Ab titers that protected mice against viral challenge. Subcutaneous (s.c.) and intranasal (i.n.) delivery of M2e-MAPs resulted in the induction of IgG in serum and airway secretions, however only i.n. immunization induced anti-M2e IgA ASCs locally in the lungs, correlating with M2-specific IgA in the bronchio-alveolar lavage (BAL). Interestingly, both routes of vaccination resulted in equal protection against viral challenge. Moreover, M2e-MAPs induced cross-reactive and protective responses to diverse M2e peptides and variant influenza viruses. However, in contrast to BALB/c mice, immunization of other inbred and outbred mouse strains did not induce protective Abs. This correlated with a defect in T cell but not B cell responsiveness to the M2e-MAPs. Conclusion/Significance Anti-M2e Abs induced by M2e-MAPs are highly cross-reactive and can mediate protection to variant viruses. Although synthetic MAPs are promising designs for vaccines, future constructs will need to be optimized for use in the genetically heterogeneous human population. PMID:22180783

Vaccination with M2e-based multiple antigenic peptides: characterization of the B cell response and protection efficacy in inbred and outbred mice.

PubMed

Wolf, Amaya I; Mozdzanowska, Krystyna; Williams, Katie L; Singer, David; Richter, Monique; Hoffmann, Ralf; Caton, Andrew J; Otvos, Laszlo; Erikson, Jan

2011-01-01

The extracellular domain of the influenza A virus protein matrix protein 2 (M2e) is remarkably conserved between various human isolates and thus is a viable target antigen for a universal influenza vaccine. With the goal of inducing protection in multiple mouse haplotypes, M2e-based multiple antigenic peptides (M2e-MAP) were synthesized to contain promiscuous T helper determinants from the Plasmodium falciparum circumsporozoite protein, the hepatitis B virus antigen and the influenza virus hemagglutinin. Here, we investigated the nature of the M2e-MAP-induced B cell response in terms of the distribution of antibody (Ab) secreting cells (ASCs) and Ab isotypes, and tested the protective efficacy in various mouse strains. Immunization of BALB/c mice with M2e-MAPs together with potent adjuvants, CpG 1826 oligonucleotides (ODN) and cholera toxin (CT) elicited high M2e-specific serum Ab titers that protected mice against viral challenge. Subcutaneous (s.c.) and intranasal (i.n.) delivery of M2e-MAPs resulted in the induction of IgG in serum and airway secretions, however only i.n. immunization induced anti-M2e IgA ASCs locally in the lungs, correlating with M2-specific IgA in the bronchio-alveolar lavage (BAL). Interestingly, both routes of vaccination resulted in equal protection against viral challenge. Moreover, M2e-MAPs induced cross-reactive and protective responses to diverse M2e peptides and variant influenza viruses. However, in contrast to BALB/c mice, immunization of other inbred and outbred mouse strains did not induce protective Abs. This correlated with a defect in T cell but not B cell responsiveness to the M2e-MAPs. Anti-M2e Abs induced by M2e-MAPs are highly cross-reactive and can mediate protection to variant viruses. Although synthetic MAPs are promising designs for vaccines, future constructs will need to be optimized for use in the genetically heterogeneous human population.

Inhibition of benzopyrene diol epoxide-induced apoptosis by cadmium (II) is AP-1-independent: role of extracelluler signal related kinase

PubMed Central

Mukherjee, Jagat J.; Gupta, Suresh K.; Kumar, Subodh

2010-01-01

Cadmium, a major metal constituent of tobacco smoke, elicits synergistic enhancement of cell transformation when combined with benzo[a]pyrene (BP) or other PAHs. The mechanism underlying this synergism is not clearly understood. We observed that (+/−)-anti-benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE), an ultimate carcinogen of BP, induces apoptosis in promotion sensitive mouse epidermal JB6 Cl41 cells at non-cytotoxic concentrations. BPDE also activates AP-1 several folds in AP-1 reporter JB6 cells. Cadmium at non-cytotoxic concentrations inhibits both AP-1 activation and apoptosis in response to BPDE. Since AP-1 is known to be involved in stress-induced apoptosis we investigated whether inhibition of AP-1 by cadmium has any role in the inhibition of BPDE-induced apoptosis. MAP kinases (particularly ERKs, p38 and JNKs) are known to have important role in DNA damage-induced AP-1 activation. We observed that ERK and JNK, but not p38 MAP kinase, are involved in BPDE-induced AP-1 activation. Effect of cadmium on MAP kinases and the effect of inhibition of above three MAP kinases on BPDE-induced AP-1 activation and apoptosis indicate that AP-1 is probably not involved in BPDE-induced apoptosis. Cadmium up-regulates BPDE-activated ERKs and ERK inhibition by U0126 relieves cadmium-mediated inhibition of BPDE-induced apoptosis. We suggest that cadmium inhibits BPDE-induced apoptosis not involving AP-1 but probably through a different mechanism by up-regulating ERK which is known to promote cell survival. PMID:18093576

Increased /sup 3/H-spiperone binding sites in mesolimbic area related to methamphetamine-induced behavioral hypersensitivity

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

Akiyama, K.; Sato, M.; Otsuki, S.

1982-02-01

The specific /sup 3/H-spiperone binding to membrane homogenates of the striatum, mesolimbic area, and frontal cortex was examined in two groups of rats pretreated once daily with saline or 4 mg/kg of methamphetamine (MAP) for 14 days. At 7 days following cessation of chronic pretreatment, all rats received an injection of 4 mg/kg of MAP and were decapitated 1 hr after the injection. In the chronic saline-pretreatment group, the single administration of MAP induced significant changes in the number (Bmax) of specific /sup 3/H-spiperone binding sites (a decrease in the striatum and an increase in the mesolimbic area and frontalmore » cortex), but no significant changes in the affinity (KD) in any brain area. The chronic MAP pretreatment markedly augmented the changes in Bmax in the striatum and mesolimbic area. The increase in specific /sup 3/H-spiperone binding sites in the mesolimbic area is discussed in relation to MAP-induced behavioral hypersensitivity.« less

Determining distinct circuit in complete graphs using permutation

NASA Astrophysics Data System (ADS)

Karim, Sharmila; Ibrahim, Haslinda; Darus, Maizon Mohd

2017-11-01

A Half Butterfly Method (HBM) is a method introduced to construct the distinct circuits in complete graphs where used the concept of isomorphism. The Half Butterfly Method was applied in the field of combinatorics such as in listing permutations of n elements. However the method of determining distinct circuit using HBM for n > 4 is become tedious. Thus, in this paper, we present the method of generating distinct circuit using permutation.

Space of states in operator BFV-formalism

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

Batalin, I.A.; Tyutin, I.V.

1993-05-15

The dynamically adequate Fock realization of the extended space of asymptotic states is given within the framework of the operator BFV-formalism and of the Dirac quantization scheme as well. Physical subspace is picked out and established to be naturally isomorphic to the Dirac space of states. The formal mechanism (unitary [var epsilon]-limit), by means of which the operator BFV-dynamics reduces to the Dirac one, is studied. 10 refs.

Using Psychometric Technology in Educational Assessment: The Case of a Schema-Based Isomorphic Approach to the Automatic Generation of Quantitative Reasoning Items

ERIC Educational Resources Information Center

Arendasy, Martin; Sommer, Markus

2007-01-01

This article deals with the investigation of the psychometric quality and constructs validity of algebra word problems generated by means of a schema-based version of the automatic min-max approach. Based on review of the research literature in algebra word problem solving and automatic item generation this new approach is introduced as a…

Quantum Algorithms Based on Physical Processes

DTIC Science & Technology

2013-12-03

quantum walks with hard-core bosons and the graph isomorphism problem,” American Physical Society March meeting, March 2011 Kenneth Rudinger, John...King Gamble, Mark Wellons, Mark Friesen, Dong Zhou, Eric Bach, Robert Joynt, and S.N. Coppersmith, “Quantum random walks of non-interacting bosons on...and noninteracting Bosons to distinguish nonisomorphic graphs. 1) We showed that quantum walks of two hard-core Bosons can distinguish all pairs of

Quantum Algorithms Based on Physical Processes

DTIC Science & Technology

2013-12-02

quantum walks with hard-core bosons and the graph isomorphism problem,” American Physical Society March meeting, March 2011 Kenneth Rudinger, John...King Gamble, Mark Wellons, Mark Friesen, Dong Zhou, Eric Bach, Robert Joynt, and S.N. Coppersmith, “Quantum random walks of non-interacting bosons on...and noninteracting Bosons to distinguish nonisomorphic graphs. 1) We showed that quantum walks of two hard-core Bosons can distinguish all pairs of

Introduction to Piezoelectric Actuators and Transducers

DTIC Science & Technology

2003-06-17

a piezo-device and a metal fork. A piezoelectric buzzer is shown in Fig. 12, which has merits such as high electric power efficiency, compact size...coefficient for surface acoustic wave and so is used for SAW devices with high -stabilized frequencies. The another distinguished characteristic of...quartz is an extremely high mechanical quality factor Qm > 10 5. Lithium niobate and lithium tantalate belong to an isomorphous crystal system and

Geometric interpretation of vertex operator algebras.

PubMed Central

Huang, Y Z

1991-01-01

In this paper, Vafa's approach to the formulation of conformal field theories is combined with the formal calculus developed in Frenkel, Lepowsky, and Meurman's work on the vertex operator construction of the Monster to give a geometric definition of vertex operator algebras. The main result announced is the equivalence between this definition and the algebraic one in the sense that the categories determined by these definitions are isomorphic. PMID:11607240

A reductionist perspective on quantum statistical mechanics: Coarse-graining of path integrals

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

Sinitskiy, Anton V.; Voth, Gregory A., E-mail: gavoth@uchicago.edu

2015-09-07

Computational modeling of the condensed phase based on classical statistical mechanics has been rapidly developing over the last few decades and has yielded important information on various systems containing up to millions of atoms. However, if a system of interest contains important quantum effects, well-developed classical techniques cannot be used. One way of treating finite temperature quantum systems at equilibrium has been based on Feynman’s imaginary time path integral approach and the ensuing quantum-classical isomorphism. This isomorphism is exact only in the limit of infinitely many classical quasiparticles representing each physical quantum particle. In this work, we present a reductionistmore » perspective on this problem based on the emerging methodology of coarse-graining. This perspective allows for the representations of one quantum particle with only two classical-like quasiparticles and their conjugate momenta. One of these coupled quasiparticles is the centroid particle of the quantum path integral quasiparticle distribution. Only this quasiparticle feels the potential energy function. The other quasiparticle directly provides the observable averages of quantum mechanical operators. The theory offers a simplified perspective on quantum statistical mechanics, revealing its most reductionist connection to classical statistical physics. By doing so, it can facilitate a simpler representation of certain quantum effects in complex molecular environments.« less

Synthesis, Structure, White-Light Emission, and Temperature Recognition Properties of Eu/Tb Mixed Coordination Polymers.

PubMed

An, Ran; Zhao, Hui; Hu, Huai-Ming; Wang, Xiaofang; Yang, Meng-Lin; Xue, Ganglin

2016-01-19

Two series of Eu(III)/Tb(III) coordination polymers, [LnL(glu)]n·2nH2O (Ln = Eu (1), Tb (2)) and [LnL(glu)(H2O)]n (Ln = Eu (3), Tb (4)) [HL = (2-(2-sulfophenyl)imidazo(4,5-f)(1,10)-phenanthroline, H2glu = glutaric acid] have been hydrothermally synthesized by controlling the pH values and characterized by elemental analysis, infrared spectra, and single-crystal X-ray diffraction. Isomorphic compounds 1 and 2 exhibit 6-connected 3D network with the pcu topological net, containing left- and right-handed helical chains. Isomorphic compounds 3 and 4 show 3,4-connected 2D new topology with the point symbol of (4(2)·6(3)·8)(4(2)·6). Multicolor luminescence can be tailored from red to green regions by singly varying the mixing molar ratio of Eu(III)/Tb(III) cations. The mixing component of 1Eu/2Tb = 4:6 not only achieves white-light emission with the CIE coordinate of (0.323, 0.339) upon excitation at 405 nm but also presents a temperature recognition property with the significantly high sensitivity of 0.68% per K in the 50-225 K temperature range upon excitation at 370 nm.

A house divided: cooperative and competitive recruitment in vital industries.

PubMed

Willis, William K; Muslin, Ivan; Timko, Karlyn N

2016-03-01

To propose a theoretical based model approach to address the nursing shortage problem of recruiting qualified applicants. Vital industries such as nursing and trucking face a large labour shortage. A literature review focusing on recruitment and realistic job previews examines relevant theories and an indication of the focus of similar research. Game theory illustrates cooperative and competitive recruitment strategies in vital industries. Proposition and model development where cooperative or competitive strategies for recruitment can either increase or decrease the employee applicant pool. Institutional theory states that firms within a population become isomorphic in nature. Firms employing cooperative or competitive strategies for recruitment can change organisational practices through isomorphic processes. Industries facing a labour market shortage using cooperative strategy will use realistic job previews accurately to disseminate information about industry jobs. Realistic job previews will increase the applicant pool through individuals self-selecting into, rather than out of, the applicant pool. Recruitment in the nursing industry has been examined at the individual applicant and organisational level, yet the overall industry has been ignored. As nursing shortages continue, viewing recruitment at the macro level (the overall industry) is appropriate. Game theory as proposed provides opportunities for current research at the industry level. © 2015 John Wiley & Sons Ltd.

Nash points, Ky Fan inequality and equilibria of abstract economies in Max-Plus and -convexity

NASA Astrophysics Data System (ADS)

Briec, Walter; Horvath, Charles

2008-05-01

-convexity was introduced in [W. Briec, C. Horvath, -convexity, Optimization 53 (2004) 103-127]. Separation and Hahn-Banach like theorems can be found in [G. Adilov, A.M. Rubinov, -convex sets and functions, Numer. Funct. Anal. Optim. 27 (2006) 237-257] and [W. Briec, C.D. Horvath, A. Rubinov, Separation in -convexity, Pacific J. Optim. 1 (2005) 13-30]. We show here that all the basic results related to fixed point theorems are available in -convexity. Ky Fan inequality, existence of Nash equilibria and existence of equilibria for abstract economies are established in the framework of -convexity. Monotone analysis, or analysis on Maslov semimodules [V.N. Kolokoltsov, V.P. Maslov, Idempotent Analysis and Its Applications, Math. Appl., volE 401, Kluwer Academic, 1997; V.P. Litvinov, V.P. Maslov, G.B. Shpitz, Idempotent functional analysis: An algebraic approach, Math. Notes 69 (2001) 696-729; V.P. Maslov, S.N. Samborski (Eds.), Idempotent Analysis, Advances in Soviet Mathematics, Amer. Math. Soc., Providence, RI, 1992], is the natural framework for these results. From this point of view Max-Plus convexity and -convexity are isomorphic Maslov semimodules structures over isomorphic semirings. Therefore all the results of this paper hold in the context of Max-Plus convexity.

A reductionist perspective on quantum statistical mechanics: Coarse-graining of path integrals.

PubMed

Sinitskiy, Anton V; Voth, Gregory A

2015-09-07

Computational modeling of the condensed phase based on classical statistical mechanics has been rapidly developing over the last few decades and has yielded important information on various systems containing up to millions of atoms. However, if a system of interest contains important quantum effects, well-developed classical techniques cannot be used. One way of treating finite temperature quantum systems at equilibrium has been based on Feynman's imaginary time path integral approach and the ensuing quantum-classical isomorphism. This isomorphism is exact only in the limit of infinitely many classical quasiparticles representing each physical quantum particle. In this work, we present a reductionist perspective on this problem based on the emerging methodology of coarse-graining. This perspective allows for the representations of one quantum particle with only two classical-like quasiparticles and their conjugate momenta. One of these coupled quasiparticles is the centroid particle of the quantum path integral quasiparticle distribution. Only this quasiparticle feels the potential energy function. The other quasiparticle directly provides the observable averages of quantum mechanical operators. The theory offers a simplified perspective on quantum statistical mechanics, revealing its most reductionist connection to classical statistical physics. By doing so, it can facilitate a simpler representation of certain quantum effects in complex molecular environments.

Direct methods in protein crystallography.

PubMed

Karle, J

1989-11-01

It is pointed out that the 'direct methods' of phase determination for small-structure crystallography do not have immediate applicability to macromolecular structures. The term 'direct methods in macromolecular crystallography' is suggested to categorize a spectrum of approaches to macromolecular structure determination in which the analyses are characterized by the use of two-phase and higher-order-phase invariants. The evaluation of the invariants is generally obtained by the use of heavy-atom techniques. The results of a number of the more recent algebraic and probabilistic studies involving isomorphous replacement and anomalous dispersion thus become valid subjects for discussion here. These studies are described and suggestions are also presented concerning future applicability. Additional discussion concerns the special techniques of filtering, the use of non-crystallographic symmetry, some features of maximum entropy and attempts to apply phase-determining formulas to the refinement of macromolecular structure. It is noted that, in addition to the continuing remarkable progress in macromolecular crystallography based on the traditional applications of isomorphous replacement and anomalous dispersion, recent valuable advances have been made in the application of non-crystallographic symmetry, in particular, to virus structures and in applications of filtering. Good progress has also been reported in the application of exact linear algebra to multiple-wavelength anomalous-dispersion investigations of structures containing anomalous scatterers of only moderate scattering power.

Hospital information system institutionalization processes in indonesian public, government-owned and privately owned hospitals.

PubMed

Handayani, P W; Hidayanto, A N; Ayuningtyas, Dumilah; Budi, Indra

2016-11-01

The Hospital Information System (HIS) could help hospitals as a public entity to provide optimal health services. One of the main challenges of HIS implementation is an institutional change. Using institutional theory as the analytical lens, this study aims to explain the institutionalization of HIS as an instance of e-health initiatives in Indonesia. Furthermore, this paper aims for hospital management and researchers to improve the understanding of the social forces that influence hospital personnel's HIS acceptance within an organizational context. We use case studies from four public, government-owned hospitals and four privately owned (public and specialty) hospitals to explain the HIS institutionalization process by exploring the three concepts of institutional theory: institutional isomorphism, institutional logic, and institutional entrepreneurship. This study reveals that differences exist between public, government-owned and private hospitals with regard to the institutionalization process: public, government-owned hospitals' management is more motivated to implement HIS to comply with the regulations, while private hospitals' management views HIS as an urgent requirement that must be achieved. The study findings also reveal that various institutional isomorphism mechanisms and forms of institutional logic emerge during the process. Finally, three factors-self-efficacy, social influence, and management support-have a significant influence on the individual acceptance of HIS. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Conformational analysis of (1. -->. 4)-. beta. -D-mannan triacetate

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

Deslandes, Y.; Marchessault, R.H.; Bluhm, T.L.

1983-01-01

In wood, algae, and tubers, glucomannans have varying mannose-to-glucose ratios (M/G). Since diffraction on glucomannans of widely varying M/G do not show significant change in unit-cell base plane dimensions, the authors have suggested that isomorphous replacement may occur in glucomannans. To further investigate this point, it has been undertaken conformational analysis of glucomannan triacetate in which the X-ray fiber diagram suggests that two nonequivalent residues make up the asymmetric unit. X-ray fiber diagrams of the triacetate of glucomannan from Tubera salep show twofold symmetry along the chain axis with a fiber repeat of 1.6 nm. This implies that the asymmetricmore » unit is composed of two pyranose rings since the virtual bond length of a single pyranose ring cannot be greater than approximately 0.54 nm. By using empirical potential functions, it could be shown that the minimum internal energy of a mannan triacetate chain corresponds to a state where contiguous mannose triacetate units are not conformationally equivalent. This supports the hypothesis of mannobiose hexaacetate as the asymmetric unit. Furthermore, introduction of glucose triacetate into the backbone did not change the minimum energy conformation, thereby lending support to the isomorphous replacement concept in crystalline glucomannans. 19 references, 13 figures, 2 tables.« less

Consistent Orientation of Moduli Spaces

NASA Astrophysics Data System (ADS)

Freed, Daniel S.; Hopkins, Michael J.; Teleman, Constantin

In a series of papers by Freed, Hopkins, and Teleman (2003, 2005, 2007a) the relationship between positive energy representations of the loop group of a compact Lie group G and the twisted equivariant K-theory Kτ+dimGG (G) was developed. Here G acts on itself by conjugation. The loop group representations depend on a choice of ‘level’, and the twisting τ is derived from the level. For all levels the main theorem is an isomorphism of abelian groups, and for special transgressed levels it is an isomorphism of rings: the fusion ring of the loop group andKτ+dimGG (G) as a ring. For G connected with π1G torsionfree, it has been proven that the ring Kτ+dimGG (G) is a quotient of the representation ring of G and can be calculated explicitly. In these cases it agrees with the fusion ring of the corresponding centrally extended loop group. This chapter explicates the multiplication on the twisted equivariant K-theory for an arbitrary compact Lie group G. It constructs a Frobenius ring structure on Kτ+dimGG (G). This is best expressed in the language of topological quantum field theory: a two-dimensional topological quantum field theory (TQFT) is constructed over the integers in which the abelian group attached to the circle is Kτ+dimGG (G).

Crystallization and preliminary X-ray analysis of a novel Kunitz-type kallikrein inhibitor from Bauhinia bauhinioides

PubMed Central

Navarro, Marcos Vicente de A. S.; Vierira, Débora F.; Nagem, Ronaldo A. P.; de Araújo, Ana Paula U.; Oliva, Maria Luiza V.; Garratt, Richard C.

2005-01-01

A Kunitz-type protease inhibitor (BbKI) found in Bauhinia bauhinioides seeds has been overexpressed in Escherichia coli and crystallized at 293 K using PEG 4000 as the precipitant. X-ray diffraction data have been collected to 1.87 Å resolution using an in-house X-ray generator. The crystals of the recombinant protein (rBbKI) belong to the orthorhombic space group P212121, with unit-cell parameters a = 46.70, b = 64.14, c = 59.24 Å. Calculation of the Matthews coefficient suggests the presence of one monomer of rBbKI in the asymmetric unit, with a corresponding solvent content of 51% (V M = 2.5 Å3 Da−1). Iodinated crystals were prepared and a derivative data set was also collected at 2.1 Å resolution. Crystals soaked for a few seconds in a cryogenic solution containing 0.5 M NaI were found to be reasonably isomorphous to the native crystals. Furthermore, the presence of iodide anions could be confirmed in the NaI-derivatized crystal. Data sets from native and derivative crystals are being evaluated for use in crystal structure determination by means of the SIRAS (single isomorphous replacement with anomalous scattering) method. PMID:16511193

Communication: Studies of the Lennard-Jones fluid in 2, 3, and 4 dimensions highlight the need for a liquid-state 1/d expansion.

PubMed

Costigliola, Lorenzo; Schrøder, Thomas B; Dyre, Jeppe C

2016-06-21

The recent theoretical prediction by Maimbourg and Kurchan [e-print arXiv:1603.05023 (2016)] that for regular pair-potential systems the virial potential-energy correlation coefficient increases towards unity as the dimension d goes to infinity is investigated for the standard 12-6 Lennard-Jones fluid. This is done by computer simulations for d = 2, 3, 4 going from the critical point along the critical isotherm/isochore to higher density/temperature. In both cases the virial potential-energy correlation coefficient increases significantly. For a given density and temperature relative to the critical point, with increasing number of dimension the Lennard-Jones system conforms better to the hidden-scale-invariance property characterized by high virial potential-energy correlations (a property that leads to the existence of isomorphs in the thermodynamic phase diagram, implying that it becomes effectively one-dimensional in regard to structure and dynamics). The present paper also gives the first numerical demonstration of isomorph invariance of structure and dynamics in four dimensions. Our findings emphasize the need for a universally applicable 1/d expansion in liquid-state theory; we conjecture that the systems known to obey hidden scale invariance in three dimensions are those for which the yet-to-be-developed 1/d expansion converges rapidly.

AUTOMATED ANALYSIS OF QUANTITATIVE IMAGE DATA USING ISOMORPHIC FUNCTIONAL MIXED MODELS, WITH APPLICATION TO PROTEOMICS DATA.

PubMed

Morris, Jeffrey S; Baladandayuthapani, Veerabhadran; Herrick, Richard C; Sanna, Pietro; Gutstein, Howard

2011-01-01

Image data are increasingly encountered and are of growing importance in many areas of science. Much of these data are quantitative image data, which are characterized by intensities that represent some measurement of interest in the scanned images. The data typically consist of multiple images on the same domain and the goal of the research is to combine the quantitative information across images to make inference about populations or interventions. In this paper, we present a unified analysis framework for the analysis of quantitative image data using a Bayesian functional mixed model approach. This framework is flexible enough to handle complex, irregular images with many local features, and can model the simultaneous effects of multiple factors on the image intensities and account for the correlation between images induced by the design. We introduce a general isomorphic modeling approach to fitting the functional mixed model, of which the wavelet-based functional mixed model is one special case. With suitable modeling choices, this approach leads to efficient calculations and can result in flexible modeling and adaptive smoothing of the salient features in the data. The proposed method has the following advantages: it can be run automatically, it produces inferential plots indicating which regions of the image are associated with each factor, it simultaneously considers the practical and statistical significance of findings, and it controls the false discovery rate. Although the method we present is general and can be applied to quantitative image data from any application, in this paper we focus on image-based proteomic data. We apply our method to an animal study investigating the effects of opiate addiction on the brain proteome. Our image-based functional mixed model approach finds results that are missed with conventional spot-based analysis approaches. In particular, we find that the significant regions of the image identified by the proposed method frequently correspond to subregions of visible spots that may represent post-translational modifications or co-migrating proteins that cannot be visually resolved from adjacent, more abundant proteins on the gel image. Thus, it is possible that this image-based approach may actually improve the realized resolution of the gel, revealing differentially expressed proteins that would not have even been detected as spots by modern spot-based analyses.

Construction of cosmic string induced temperature anisotropy maps with CMBFAST and statistical analysis

NASA Astrophysics Data System (ADS)

Simatos, N.; Perivolaropoulos, L.

2001-01-01

We use the publicly available code CMBFAST, as modified by Pogosian and Vachaspati, to simulate the effects of wiggly cosmic strings on the cosmic microwave background (CMB). Using the modified CMBFAST code, which takes into account vector modes and models wiggly cosmic strings by the one-scale model, we go beyond the angular power spectrum to construct CMB temperature maps with a resolution of a few degrees. The statistics of these maps are then studied using conventional and recently proposed statistical tests optimized for the detection of hidden temperature discontinuities induced by the Gott-Kaiser-Stebbins effect. We show, however, that these realistic maps cannot be distinguished in a statistically significant way from purely Gaussian maps with an identical power spectrum.

Serum-induced neurite retraction in CAD cells--involvement of an ATP-actin retractile system and the lack of microtubule-associated proteins.

PubMed

Chesta, María E; Carbajal, Agustín; Arce, Carlos A; Bisig, Carlos G

2014-11-01

Cultured catecholamine-differentiated cells [which lack the microtubule-associated proteins (MAPs): MAP1B, MAP2, Tau, STOP, and Doublecortin] proliferate in the presence of fetal bovine serum, and, in its absence, cease dividing and generate processes similar to the neurites of normal neurons. The reintroduction of serum induces neurite retraction, and proliferation resumes. The neurite retraction process in catecholamine-differentiated cells was partially characterized in this study. Microtubules in the cells were found to be in a highly dynamic state, and tubulin in the microtubules consisted primarily of the tyrosinated and deacetylated isotypes. Increased levels of acetylated or Δ2-tubulin (which are normally absent) did not prevent serum-induced neurite retraction. Treatment of differentiated cells with lysophosphatidic acid or adenosine deaminase induced neurite retraction. Inhibition of Rho-associated protein kinase, ATP depletion and microfilament disruption each (individually) blocked serum-induced neurite retraction, suggesting that an ATP-dependent actomyosin system underlies the mechanism of neurite retraction. Nocodazole treatment induced neurite retraction, but this effect was blocked by pretreatment with the microtubule-stabilizing drug paclitaxel (Taxol). Paclitaxel did not prevent serum-induced or lysophosphatidic acid-induced retraction, suggesting that integrity of microtubules (despite their dynamic state) is necessary to maintain neurite elongation, and that paclitaxel-induced stabilization alone is not sufficient to resist the retraction force induced by serum. Transfection with green fluorescent protein-Tau conferred resistance to retraction caused by serum. We hypothesize that, in normal neurons (cultured or in vivo), MAPs are necessary not only to stabilize microtubules, but also to establish interactions with other cytoskeletal or membrane components to form a stable structure capable of resisting the retraction force. © 2014 FEBS.

Proteolytic Inhibition of Salmonella enterica Serovar Typhimurium-Induced Activation of the Mitogen-Activated Protein Kinases ERK and JNK in Cultured Human Intestinal Cells

PubMed Central

Mynott, Tracey L.; Crossett, Ben; Prathalingam, S. Radhika

2002-01-01

Bromelain, a mixture of cysteine proteases from pineapple stems, blocks signaling by the mitogen-activated protein (MAP) kinases extracellular regulated kinase 1 (ERK-1) and ERK-2, inhibits inflammation, and protects against enterotoxigenic Escherichia coli infection. In this study, we examined the effect of bromelain on Salmonella enterica serovar Typhimurium infection, since an important feature of its pathogenesis is its ability to induce activation of ERK-1 and ERK-2, which leads to internalization of bacteria and induction of inflammatory responses. Our results show that bromelain dose dependently blocks serovar Typhimurium-induced ERK-1, ERK-2, and c-Jun NH2-terminal kinase (JNK) activation in Caco-2 cells. Bromelain also blocked signaling induced by carbachol and anisomycin, pharmacological MAP kinase agonists. Despite bromelain inhibition of serovar Typhimurium-induced MAP kinase signaling, it did not prevent subsequent invasion of the Caco-2 cells by serovar Typhimurium or alter serovar Typhimurium -induced decreases in resistance across Caco-2 monolayers. Surprisingly, bromelain also did not block serovar Typhimurium-induced interleukin-8 (IL-8) secretion but synergized with serovar Typhimurium to enhance IL-8 production. We also found that serovar Typhimurium does not induce ERK phosphorylation in Caco-2 cells in the absence of serum but that serovar Typhimurium-induced invasion and decreases in monolayer resistance are unaffected. Collectively, these data indicate that serovar Typhimurium-induced invasion of Caco-2 cells, changes in the resistance of epithelial cell monolayers, and IL-8 production can occur independently of the ERK and JNK signaling pathways. Data also confirm that bromelain is a novel inhibitor of MAP kinase signaling pathways and suggest a novel role for proteases as inhibitors of signal transduction pathways in intestinal epithelial cells. PMID:11748167

Human TTR conformation altered by rhenium tris-carbonyl derivatives.

PubMed

Ciccone, Lidia; Policar, Clotilde; Stura, Enrico A; Shepard, William

2016-09-01

Transthyretin (TTR) is a 54 kDa homotetrameric serum protein that transports thyroxine (T4) and retinol. TTR is potentially amyloidogenic due to homotetramer dissociation into monomeric intermediates that self-assemble as amyloid deposits and insoluble fibrils. Most crystallographic structures, including those of amyloidogenic variants show the same tetramer without major variations in the monomer-monomer interface nor in the volume of the interdimeric cavity. Soaking TTR crystals in a solution containing rhenium tris-carbonyl derivatives yields a TTR conformer never observed before. Only one of the two monomers of the crystallographic dimer is significantly altered, and the inner part of the T4 binding cavity is expanded at one end and shrunk at the other. The result redefines the mechanism of allosteric communication between the two sites, suggesting that negative cooperativity is a function of dimer asymmetry, which can be induced through internal or external binding. An aspect that remains unexplained is why the conformational changes are ubiquitous throughout the crystal although the heavy metal content of the derivatized crystals is relatively low. The conformational changes observed, which include Leu(82), may represent a form of TTR better at scavenging β-Amyloid. At a resolution of 1.69Å, with excellent refinement statistics and well defined electron density for all parts of the structure, it is possible to envisage answering important questions that range from protein cooperative behavior to heavy atom induced protein conformational modifications that can result in crystallographic non-isomorphism. Copyright © 2016 Elsevier Inc. All rights reserved.

Development of regional liquefaction-induced deformation hazard maps

USGS Publications Warehouse

Rosinski, A.; Knudsen, K.-L.; Wu, J.; Seed, R.B.; Real, C.R.; ,

2004-01-01

This paper describes part of a project to assess the feasibility of producing regional (1:24,000-scale) liquefaction hazard maps that are based-on potential liquefaction-induced deformation. The study area is the central Santa Clara Valley, at the south end of San Francisco Bay in Central California. The information collected and used includes: a) detailed Quaternary geological mapping, b) over 650 geotechnical borings, c) probabilistic earthquake shaking information, and d) ground-water levels. Predictions of strain can be made using either empirical formulations or numerical simulations. In this project lateral spread displacements are estimated and new empirical relations to estimate future volumetric and shear strain are used. Geotechnical boring data to are used to: (a) develop isopach maps showing the thickness of sediment thatis likely to liquefy and deform under earthquake shaking; and (b) assess the variability in engineering properties within and between geologic map units. Preliminary results reveal that late Holocene deposits are likely to experience the greatest liquefaction-induced strains, while Holocene and late Pleistocene deposits are likely to experience significantly less horizontal and vertical strain in future earthquakes. Development of maps based on these analyses is feasible.

Predictors of methamphetamine psychosis: History of ADHD-relevant childhood behaviors and drug exposure

PubMed Central

Salo, Ruth; Fassbender, Catherine; Iosif, Ana- Maria; Ursu, Stefan; Leamon, Martin H; Cameron, Carter

2013-01-01

The goal of this study was to extend our previous research that reported a significant association between Attention Deficit Hyperactivity Disorder (ADHD)-relevant childhood behaviors and the frequency of methamphetamine (MA)-induced psychotic symptoms in an expanded sample. 190 participants who met DSM-IV criteria for MA dependence were administered the Methamphetamine Experience Questionnaire that assessed MA-induced psychosis. Data related to MA exposure, comorbid drug use, education, familial psychiatric history and assessments of ADHD-relevant childhood behaviors as measured by the Wender Utah Rating Scale (WURS) were collected. Although WURS scores did not differ between 145 MAP+ and 45 MAP-subjects, MAP+ subjects with higher WURS scores were significantly more likely to report more frequent psychosis. Although mean daily MA dosage did not differ between the MAP+ and MAP- subjects, MAP+ who consumed larger doses of MA were significantly more likely to experience frequent psychosis. These data suggest that ADHD-relevant childhood behaviors may interact with MA exposure to reflect a neurobiological vulnerability related to the emergence of frequent MA-induced psychotic symptoms. These results may elucidate factors that contribute to the psychiatric sequelae of MA abuse. PMID:23896355

Predictors of methamphetamine psychosis: history of ADHD-relevant childhood behaviors and drug exposure.

PubMed

Salo, Ruth; Fassbender, Catherine; Iosif, Ana-Maria; Ursu, Stefan; Leamon, Martin H; Carter, Cameron

2013-12-15

The goal of this study was to extend our previous research that reported a significant association between Attention Deficit Hyperactivity Disorder (ADHD)-relevant childhood behaviors and the frequency of methamphetamine (MA)-induced psychotic symptoms in an expanded sample. 190 participants who met DSM-IV criteria for MA dependence were administered the Methamphetamine Experience Questionnaire that assessed MA-induced psychosis. Data related to MA exposure, comorbid drug use, education, familial psychiatric history and assessments of ADHD-relevant childhood behaviors as measured by the Wender Utah Rating Scale (WURS) were collected. Although WURS scores did not differ between 145 MAP+ and 45 MAP- subjects, MAP+ subjects with higher WURS scores were significantly more likely to report more frequent psychosis. Although mean daily MA dosage did not differ between the MAP+ and MAP- subjects, MAP+ subjects who consumed larger doses of MA were significantly more likely to experience frequent psychosis. These data suggest that ADHD-relevant childhood behaviors may interact with MA exposure to reflect a neurobiological vulnerability related to the emergence of frequent MA-induced psychotic symptoms. These results may elucidate factors that contribute to the psychiatric sequelae of MA abuse. © 2013 Elsevier Ireland Ltd. All rights reserved.

Influence of Betaxolol on the Methamphetamine Dependence in Mice.

PubMed

Kim, Byoung-Jo; Park, Jong-Il; Eun, Hun-Jeong; Yang, Jong-Chul

2016-05-01

The noradrenaline system is involved in the reward effects of various kinds of abused drugs. Betaxolol (BTX) is a highly selective β1-antagonist. In the present study, we evaluated the effect of BTX on methamphetamine (MAP)-induced conditioned place preference (CPP) and hyperactivity in mice. The mice (n=72) were treated with MAP or saline every other day for a total of 6 days (from day 3 to day 8; 3-times MAP and 3-times saline). Each mouse was given saline (1 mL/kg) or MAP (1 mg/kg, s.c.) or BTX (5 mg/kg, i.p.) or MAP with BTX (5 mg/kg, i.p.) 30 min prior to the administration of MAP (1 mg/kg, s.c.) every other day and paired with for 1 h (three-drug and three-saline sessions). We then compared the CPP score between the two groups. After the extinction of CPP, the mice were given BTX (5 mg/kg, i.p.) or saline (1 mL/kg) 24 h prior to a priming injection of MAP, and were then immediately tested to see whether the place preference was reinstated. The repeated administration of BTX 30 min prior to the exposure to MAP significantly reduced the development of MAP-induced CPP. When BTX was administered 24 h prior to the CPP-testing session on day 9, it also significantly attenuated the CPP, but did not result in any change of locomotor activity. In the drug-priming reinstatement study, the extinguished CPP was reinstated by a MAP (0.125 mg/kg, s.c.) injection and this was significantly attenuated by BTX. These findings suggest that BTX has a therapeutic and preventive effect on the development, expression, and drug-priming reinstatement of MAP-induced CPP.

Topological defects in open string field theory

NASA Astrophysics Data System (ADS)

Kojita, Toshiko; Maccaferri, Carlo; Masuda, Toru; Schnabl, Martin

2018-04-01

We show how conformal field theory topological defects can relate solutions of open string field theory for different boundary conditions. To this end we generalize the results of Graham and Watts to include the action of defects on boundary condition changing fields. Special care is devoted to the general case when nontrivial multiplicities arise upon defect action. Surprisingly the fusion algebra of defects is realized on open string fields only up to a (star algebra) isomorphism.

MaterialsSemicrystallineCopolyamidesBased on the Renewable Monomer, 1,9-Nonane Diamine

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

Alex Kugal; Jie He; James Bahr

The conclusions of the presentation are: (1) Confirmed Isomorphism; (2) Reproduced Sigmoidal Relationship Between Melting Temperature and Composition; (3) Tg Increased with Increasing 9T Content; (4) Thermal Stability Increased with Increasing 9T Content; (5) Crystallization Rate Increased Dramatically at 9T Contents Above 50 Mole %; and (6) Copolymers Possessing a 9T Content Exceeding 50 Mole % 9T Possess Very Desirable Thermal Properties That Rival Nylon 6,6.

On Equimultiple Subvarieties of Algebroid Hypersurfaces

PubMed Central

Zariski, Oscar

1975-01-01

We deal with a finite projection πv of a hypersurface V in (r + 1)-space onto an affine r-space Ar and with the critical variety Δ of πv in Ar. We show that if Δ is equimultiple along a smooth subvariety W0, then W0 admits a unique lifting to a subvariety W of V (necessarily isomorphic to W0) and that also V is then equimultiple along W. PMID:16592239

Internally connected graphs and the Kashiwara-Vergne Lie algebra

NASA Astrophysics Data System (ADS)

Felder, Matteo

2018-06-01

It is conjectured that the Kashiwara-Vergne Lie algebra \\widehat{krv}_2 is isomorphic to the direct sum of the Grothendieck-Teichmüller Lie algebra grt_1 and a one-dimensional Lie algebra. In this paper, we use the graph complex of internally connected graphs to define a nested sequence of Lie subalgebras of \\widehat{krv}_2 whose intersection is grt_1, thus giving a way to interpolate between these two Lie algebras.

Water Induced Hazard Mapping in Nepal: A Case Study of East Rapti River Basin

NASA Astrophysics Data System (ADS)

Neupane, N.

2010-12-01

This paper presents illustration on typical water induced hazard mapping of East Rapti River Basin under the DWIDP, GON. The basin covers an area of 2398 sq km. The methodology includes making of base map of water induced disaster in the basin. Landslide hazard maps were prepared by SINMAP approach. Debris flow hazard maps were prepared by considering geology, slope, and saturation. Flood hazard maps were prepared by using two approaches: HEC-RAS and Satellite Imagery Interpretation. The composite water-induced hazard maps were produced by compiling the hazards rendered by landslide, debris flow, and flood. The monsoon average rainfall in the basin is 1907 mm whereas maximum 24 hours precipitation is 456.8 mm. The peak discharge of the Rapati River in the year of 1993 at station was 1220 cu m/sec. This discharge nearly corresponds to the discharge of 100-year return period. The landslides, floods, and debris flows triggered by the heavy rain of July 1993 claimed 265 lives, affected 148516 people, and damaged 1500 houses in the basin. The field investigation and integrated GIS interpretation showed that the very high and high landslide hazard zones collectively cover 38.38% and debris flow hazard zone constitutes 6.58%. High flood hazard zone occupies 4.28% area of the watershed. Mitigation measures are recommendated according to Integrated Watershed Management Approach under which the non-structural and structural measures are proposed. The non-structural measures includes: disaster management training, formulation of evacuation system (arrangement of information plan about disaster), agriculture management practices, protection of water sources, slope protections and removal of excessive bed load from the river channel. Similarly, structural measures such as dike, spur, rehabilitation of existing preventive measures and river training at some locations are recommendated. The major factors that have contributed to induce high incidences of various types of mass movements and inundation in the basin are rock and soil properties, prolonged and high-intensity rainfall, steep topography and various anthropogenic factors.

Decomposition of Fuzzy Soft Sets with Finite Value Spaces

PubMed Central

Jun, Young Bae

2014-01-01

The notion of fuzzy soft sets is a hybrid soft computing model that integrates both gradualness and parameterization methods in harmony to deal with uncertainty. The decomposition of fuzzy soft sets is of great importance in both theory and practical applications with regard to decision making under uncertainty. This study aims to explore decomposition of fuzzy soft sets with finite value spaces. Scalar uni-product and int-product operations of fuzzy soft sets are introduced and some related properties are investigated. Using t-level soft sets, we define level equivalent relations and show that the quotient structure of the unit interval induced by level equivalent relations is isomorphic to the lattice consisting of all t-level soft sets of a given fuzzy soft set. We also introduce the concepts of crucial threshold values and complete threshold sets. Finally, some decomposition theorems for fuzzy soft sets with finite value spaces are established, illustrated by an example concerning the classification and rating of multimedia cell phones. The obtained results extend some classical decomposition theorems of fuzzy sets, since every fuzzy set can be viewed as a fuzzy soft set with a single parameter. PMID:24558342

Decomposition of fuzzy soft sets with finite value spaces.

PubMed

Feng, Feng; Fujita, Hamido; Jun, Young Bae; Khan, Madad

2014-01-01

The notion of fuzzy soft sets is a hybrid soft computing model that integrates both gradualness and parameterization methods in harmony to deal with uncertainty. The decomposition of fuzzy soft sets is of great importance in both theory and practical applications with regard to decision making under uncertainty. This study aims to explore decomposition of fuzzy soft sets with finite value spaces. Scalar uni-product and int-product operations of fuzzy soft sets are introduced and some related properties are investigated. Using t-level soft sets, we define level equivalent relations and show that the quotient structure of the unit interval induced by level equivalent relations is isomorphic to the lattice consisting of all t-level soft sets of a given fuzzy soft set. We also introduce the concepts of crucial threshold values and complete threshold sets. Finally, some decomposition theorems for fuzzy soft sets with finite value spaces are established, illustrated by an example concerning the classification and rating of multimedia cell phones. The obtained results extend some classical decomposition theorems of fuzzy sets, since every fuzzy set can be viewed as a fuzzy soft set with a single parameter.

Chalcogen analogues of nicotine lactam studied by NMR, FTIR, DFT and X-ray methods

NASA Astrophysics Data System (ADS)

Jasiewicz, Beata; Malczewska-Jaskóła, Karolina; Kowalczyk, Iwona; Warżajtis, Beata; Rychlewska, Urszula

2014-07-01

The selenoanalogue of nicotine has been synthesized and characterized by spectroscopic and X-ray diffraction methods. The crystals of selenonicotine are isomorphic with the thionicotine homologue and consist of molecules engaged in columnar π⋯π stacking interactions between antiparallely arranged pyridine moieties. These interactions, absent in other crystals containing nicotine fragments, seem to be induced by the presence of a lactam group. The molecular structures in the vacuum of the oxo-, thio- and selenonicotine homologues have been calculated by the DFT method and compared with the available X-ray data. The delocalized structure of thionicotine is stabilized by intramolecular Csbnd H⋯S hydrogen bond, which becomes weaker in the partial zwitterionic resonance structure of selenonicotine in favor of multiple Csbnd H⋯Se intermolecular hydrogen-bonds. The calculated data allow a complete assignment of vibration modes in the solid state FTIR spectra. The 1H and 13C NMR chemical shifts were calculated by the GIAO method with B3LYP/6-311G(3df) level. A comparison between experimental and calculated theoretical results indicates that the density functional B3LYP method provided satisfactory results for predicting FTIR, 1H, 13C NMR spectra properties.

Structural Basis for the Kexin-like Serine Protease from Aeromonas sobria as Sepsis-causing Factor*

PubMed Central

Kobayashi, Hidetomo; Utsunomiya, Hiroko; Yamanaka, Hiroyasu; Sei, Yoshihisa; Katunuma, Nobuhiko; Okamoto, Keinosuke; Tsuge, Hideaki

2009-01-01

The anaerobic bacterium Aeromonas sobria is known to cause potentially lethal septic shock. We recently proposed that A. sobria serine protease (ASP) is a sepsis-related factor that induces vascular leakage, reductions in blood pressure via kinin release, and clotting via activation of prothrombin. ASP preferentially cleaves peptide bonds that follow dibasic amino acid residues, as do Kex2 (Saccharomyces cerevisiae serine protease) and furin, which are representative kexin family proteases. Here, we revealed the crystal structure of ASP at 1.65 Å resolution using the multiple isomorphous replacement method with anomalous scattering. Although the overall structure of ASP resembles that of Kex2, it has a unique extra occluding region close to its active site. Moreover, we found that a nicked ASP variant is cleaved within the occluding region. Nicked ASP shows a greater ability to cleave small peptide substrates than the native enzyme. On the other hand, the cleavage pattern for prekallikrein differs from that of ASP, suggesting the occluding region is important for substrate recognition. The extra occluding region of ASP is unique and could serve as a useful target to facilitate development of novel antisepsis drugs. PMID:19654332

Oversampling the Minority Class in the Feature Space.

PubMed

Perez-Ortiz, Maria; Gutierrez, Pedro Antonio; Tino, Peter; Hervas-Martinez, Cesar

2016-09-01

The imbalanced nature of some real-world data is one of the current challenges for machine learning researchers. One common approach oversamples the minority class through convex combination of its patterns. We explore the general idea of synthetic oversampling in the feature space induced by a kernel function (as opposed to input space). If the kernel function matches the underlying problem, the classes will be linearly separable and synthetically generated patterns will lie on the minority class region. Since the feature space is not directly accessible, we use the empirical feature space (EFS) (a Euclidean space isomorphic to the feature space) for oversampling purposes. The proposed method is framed in the context of support vector machines, where the imbalanced data sets can pose a serious hindrance. The idea is investigated in three scenarios: 1) oversampling in the full and reduced-rank EFSs; 2) a kernel learning technique maximizing the data class separation to study the influence of the feature space structure (implicitly defined by the kernel function); and 3) a unified framework for preferential oversampling that spans some of the previous approaches in the literature. We support our investigation with extensive experiments over 50 imbalanced data sets.

Dynamic maps of UV damage formation and repair for the human genome

PubMed Central

Hu, Jinchuan; Adebali, Ogun; Adar, Sheera; Sancar, Aziz

2017-01-01

Formation and repair of UV-induced DNA damage in human cells are affected by cellular context. To study factors influencing damage formation and repair genome-wide, we developed a highly sensitive single-nucleotide resolution damage mapping method [high-sensitivity damage sequencing (HS–Damage-seq)]. Damage maps of both cyclobutane pyrimidine dimers (CPDs) and pyrimidine-pyrimidone (6-4) photoproducts [(6-4)PPs] from UV-irradiated cellular and naked DNA revealed that the effect of transcription factor binding on bulky adducts formation varies, depending on the specific transcription factor, damage type, and strand. We also generated time-resolved UV damage maps of both CPDs and (6-4)PPs by HS–Damage-seq and compared them to the complementary repair maps of the human genome obtained by excision repair sequencing to gain insight into factors that affect UV-induced DNA damage and repair and ultimately UV carcinogenesis. The combination of the two methods revealed that, whereas UV-induced damage is virtually uniform throughout the genome, repair is affected by chromatin states, transcription, and transcription factor binding, in a manner that depends on the type of DNA damage. PMID:28607063

Dynamic maps of UV damage formation and repair for the human genome.

PubMed

Hu, Jinchuan; Adebali, Ogun; Adar, Sheera; Sancar, Aziz

2017-06-27

Formation and repair of UV-induced DNA damage in human cells are affected by cellular context. To study factors influencing damage formation and repair genome-wide, we developed a highly sensitive single-nucleotide resolution damage mapping method [high-sensitivity damage sequencing (HS-Damage-seq)]. Damage maps of both cyclobutane pyrimidine dimers (CPDs) and pyrimidine-pyrimidone (6-4) photoproducts [(6-4)PPs] from UV-irradiated cellular and naked DNA revealed that the effect of transcription factor binding on bulky adducts formation varies, depending on the specific transcription factor, damage type, and strand. We also generated time-resolved UV damage maps of both CPDs and (6-4)PPs by HS-Damage-seq and compared them to the complementary repair maps of the human genome obtained by excision repair sequencing to gain insight into factors that affect UV-induced DNA damage and repair and ultimately UV carcinogenesis. The combination of the two methods revealed that, whereas UV-induced damage is virtually uniform throughout the genome, repair is affected by chromatin states, transcription, and transcription factor binding, in a manner that depends on the type of DNA damage.

Microtubule-associated protein 1S-related autophagy inhibits apoptosis of intestinal epithelial cells via Wnt/β-catenin signaling in Crohn's disease.

PubMed

Bai, Wenxia; Bai, Jian'an; Li, Yanhai; Tian, Delong; Shi, Ruihua

2017-04-08

Many autophagy-related genes, to our knowledge, have been identified as Crohn's disease (CD) polymorphic sites by genomic wide studies. As a novel member of the microtubule-associated protein 1 (MAP1) family, MAP1S is a microtubule-binding proteins involved in autophagy. However, its expression and potential functions in CD have not been understood. For the first time, we discovered the up-regulated MAP1S and autophagy level (indicated by LC3-Ⅱ/LC3-Ⅰ) in inflamed epithelium among CD patients. Similarly, in TNBS-induced murine colitis model, MAP1S expression was obviously increased. Meanwhile, we found the co-location of MAP1S and active-caspase 3 which acted as "apoptotic executor" which might indicate the basis of their co-efficient. At the cellular level, MAP1S silencing inhibited starvation-induced over-expression of active-caspase 3 partially via Wnt/β-catenin signaling activation in HCT-116 cells. Finally, we demonstrated that IWP-2, an inhibitor of the Wnt/β-catenin signaling, reversed the down-regulation of active-caspase 3 induced by MAP1S siRNA in HCT-116 cells. Taken together, our results suggested that MAP1S were up-regulated among CD patients and MAP1S-related autophagy inhibits apoptosis of intestinal epithelial cells (IECs) through Wnt/β-catenin signaling pathway which might play a vital role in the protection of intestinal mucosal barrier and inhibition the progression of CD. Copyright © 2017 Elsevier Inc. All rights reserved.

Storm-Induced Slope Failure Susceptibility Mapping

DOT National Transportation Integrated Search

2018-01-01

A pilot study was conducted to characterize and map the areas susceptible to slope failure using state-wide available data. The objective was to determine whether it would be possible to provide slope-failure susceptibility mapping that could be used...

cGAS-STING-TBK1-IRF3/7 induced interferon-β contributes to the clearing of non tuberculous mycobacterial infection in mice.

PubMed

Ruangkiattikul, Nanthapon; Nerlich, Andreas; Abdissa, Ketema; Lienenklaus, Stefan; Suwandi, Abdulhadi; Janze, Nina; Laarmann, Kristin; Spanier, Julia; Kalinke, Ulrich; Weiss, Siegfried; Goethe, Ralph

2017-10-03

Type I interferons (IFN-I), such as IFN-α and IFN-β are important messengers in the host response against bacterial infections. Knowledge about the role of IFN-I in infections by nontuberculous mycobacteria (NTM) is limited. Here we show that macrophages infected with pathogens of the Mycobacterium avium complex produced significantly lower amounts of IFN-β than macrophages infected with the opportunistic pathogen M. smegmatis. To dissect the molecular mechanisms of this phenomenon, we focused on the obligate pathogen Mycobacterium avium ssp paratuberculosis (MAP) and the opportunistic M. smegmatis. Viability of both bacteria was required for induction of IFN-β in macrophages. Both bacteria induced IFN-β via the cGAS-STING-TBK1-IRF3/7-pathway of IFN-β activation. Stronger phosphorylation of TBK1 and higher amounts of extracellular bacterial DNA in the macrophage cytosol were found in M. smegmatis infected macrophages than in MAP infected macrophages. After intraperitoneal infection of mice, a strong Ifnb induction by M. smegmatis correlated with clearance of the bacteria. In contrast, MAP only induced weak Ifnb expression which correlated with bacterial persistence and increased number of granulomas in the liver. In mice lacking the type I interferon receptor we observed improved survival of M. smegmatis while survival of MAP was similar to that in wildtype mice. On the other hand, treatment of MAP infected wildtype mice with the IFN-I inducer poly(I:C) or recombinant IFN-β impaired the survival of MAP. This indicates an essential role of IFN-I in clearing infections by MAP and M. smegmatis. The expression level of IFN-I is decisive for transient versus persistent NTM infection.

cGAS-STING-TBK1-IRF3/7 induced interferon-β contributes to the clearing of non tuberculous mycobacterial infection in mice

PubMed Central

Ruangkiattikul, Nanthapon; Nerlich, Andreas; Abdissa, Ketema; Lienenklaus, Stefan; Suwandi, Abdulhadi; Janze, Nina; Laarmann, Kristin; Spanier, Julia; Kalinke, Ulrich; Weiss, Siegfried; Goethe, Ralph

2017-01-01

Abstract Type I interferons (IFN-I), such as IFN-α and IFN-β are important messengers in the host response against bacterial infections. Knowledge about the role of IFN-I in infections by nontuberculous mycobacteria (NTM) is limited. Here we show that macrophages infected with pathogens of the Mycobacterium avium complex produced significantly lower amounts of IFN-β than macrophages infected with the opportunistic pathogen M. smegmatis. To dissect the molecular mechanisms of this phenomenon, we focused on the obligate pathogen Mycobacterium avium ssp paratuberculosis (MAP) and the opportunistic M. smegmatis. Viability of both bacteria was required for induction of IFN-β in macrophages. Both bacteria induced IFN-β via the cGAS-STING-TBK1-IRF3/7-pathway of IFN-β activation. Stronger phosphorylation of TBK1 and higher amounts of extracellular bacterial DNA in the macrophage cytosol were found in M. smegmatis infected macrophages than in MAP infected macrophages. After intraperitoneal infection of mice, a strong Ifnb induction by M. smegmatis correlated with clearance of the bacteria. In contrast, MAP only induced weak Ifnb expression which correlated with bacterial persistence and increased number of granulomas in the liver. In mice lacking the type I interferon receptor we observed improved survival of M. smegmatis while survival of MAP was similar to that in wildtype mice. On the other hand, treatment of MAP infected wildtype mice with the IFN-I inducer poly(I:C) or recombinant IFN-β impaired the survival of MAP. This indicates an essential role of IFN-I in clearing infections by MAP and M. smegmatis. The expression level of IFN-I is decisive for transient versus persistent NTM infection. PMID:28422568

[A retrieval method of drug molecules based on graph collapsing].

PubMed

Qu, J W; Lv, X Q; Liu, Z M; Liao, Y; Sun, P H; Wang, B; Tang, Z

2018-04-18

To establish a compact and efficient hypergraph representation and a graph-similarity-based retrieval method of molecules to achieve effective and efficient medicine information retrieval. Chemical structural formula (CSF) was a primary search target as a unique and precise identifier for each compound at the molecular level in the research field of medicine information retrieval. To retrieve medicine information effectively and efficiently, a complete workflow of the graph-based CSF retrieval system was introduced. This system accepted the photos taken from smartphones and the sketches drawn on tablet personal computers as CSF inputs, and formalized the CSFs with the corresponding graphs. Then this paper proposed a compact and efficient hypergraph representation for molecules on the basis of analyzing factors that directly affected the efficiency of graph matching. According to the characteristics of CSFs, a hierarchical collapsing method combining graph isomorphism and frequent subgraph mining was adopted. There was yet a fundamental challenge, subgraph overlapping during the collapsing procedure, which hindered the method from establishing the correct compact hypergraph of an original CSF graph. Therefore, a graph-isomorphism-based algorithm was proposed to select dominant acyclic subgraphs on the basis of overlapping analysis. Finally, the spatial similarity among graphical CSFs was evaluated by multi-dimensional measures of similarity. To evaluate the performance of the proposed method, the proposed system was firstly compared with Wikipedia Chemical Structure Explorer (WCSE), the state-of-the-art system that allowed CSF similarity searching within Wikipedia molecules dataset, on retrieval accuracy. The system achieved higher values on mean average precision, discounted cumulative gain, rank-biased precision, and expected reciprocal rank than WCSE from the top-2 to the top-10 retrieved results. Specifically, the system achieved 10%, 1.41, 6.42%, and 1.32% higher than WCSE on these metrics for top-10 retrieval results, respectively. Moreover, several retrieval cases were presented to intuitively compare with WCSE. The results of the above comparative study demonstrated that the proposed method outperformed the existing method with regard to accuracy and effectiveness. This paper proposes a graph-similarity-based retrieval approach for medicine information. To obtain satisfactory retrieval results, an isomorphism-based algorithm is proposed for dominant subgraph selection based on the subgraph overlapping analysis, as well as an effective and efficient hypergraph representation of molecules. Experiment results demonstrate the effectiveness of the proposed approach.

Additive equivalence in turbulent drag reduction by flexible and rodlike polymers.

PubMed

Benzi, Roberto; Ching, Emily S C; Lo, T S; L'vov, Victor S; Procaccia, Itamar

2005-07-01

We address the additive equivalence discovered by Virk and co-workers: drag reduction affected by flexible and rigid rodlike polymers added to turbulent wall-bounded flows is limited from above by a very similar maximum drag reduction (MDR) asymptote. Considering the equations of motion of rodlike polymers in wall-bounded turbulent ensembles, we show that although the microscopic mechanism of attaining the MDR is very different, the macroscopic theory is isomorphic, rationalizing the interesting experimental observations.

Significant enhancement of gas uptake capacity and selectivity via the judicious increase of open metal sites and Lewis basic sites within two polyhedron-based metal-organic frameworks.

PubMed

Liu, Bing; Yao, Shuo; Shi, Chao; Li, Guanghua; Huo, Qisheng; Liu, Yunling

2016-02-21

Two new isomorphous polyhedron-based MOFs ( and ), with dual functionalities of OMSs and LBSs, have been synthesized by using the SBB strategy. By judiciously avoiding the DABCO axial ligand, possesses more OMSs than , and exhibits a significant enhancement of CO2 uptake capacity 210 versus 162 cm(3) g(-1) for at 273 K under 1 bar.

Rondorfite-type structure — XPS and UV–vis study

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

Dulski, M., E-mail: mateusz.dulski@smcebi.edu.pl; A.Chelkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice; Bilewska, K., E-mail: kbilewska@us.edu.pl

2015-10-15

Highlights: • Structural and spectroscopic characterization of chlorosilicate mineral, rondorfite. • Characterization of main photoemission lines and valence band spectra. • The study of color origin’s using UV–vis spectroscopy. • Analysis of structural changes in context of origin of natural fluorescence. • Discussion of a new application possibilities of analyzed mineral - Abstract: This paper focuses on X-ray diffraction, X-ray photoelectron and UV–vis spectroscopy of two different (green, orange) rondorfite samples. The differences in the sample color originate from various O/Cl ratios. The orange color was found to be related either to the isomorphic substitution of Fe{sup 3+}/Al{sup 3+} formore » Mg{sup 2+}, the presence of atypical [MgO{sub 4}] tetrahedrons in crystal structure or electronegativity of the sample. The tetrahedron is known to be very prone to accumulation of impurities and substitute atoms. Moreover, the XPS data showed tetrahedrally coordinated Mg{sup 2+} and isomorphic substitution of Al{sup 3+}/Fe{sup 3+} for Mg{sup 2+}, which influences local disordering and the point defects density and distribution. Non-equilibrium chlorine positions inside the crystal cages as well as Ca-Cl bonds have also been found. The XPS measurements as a function of temperature indicate occurrence of a structural transformation at about 770 K which is accompanied by a rotation of silicate tetrahedra within magnesiosilicate pentamer and luminescence disappearance.« less

Visible and NIR photoluminescence properties of a series of novel lanthanide-organic coordination polymers based on hydroxyquinoline-carboxylate ligands.

PubMed

Gai, Yan-Li; Xiong, Ke-Cai; Chen, Lian; Bu, Yang; Li, Xing-Jun; Jiang, Fei-Long; Hong, Mao-Chun

2012-12-17

A series of novel two-dimensional (2D) lanthanide coordination polymers with 4-hydroxyquinoline-2-carboxylate (H(2)hqc) ligands, [Ln(Hhqc)(3)(H(2)O)](n)·3nH(2)O (Ln = Eu (1), Tb (2), Sm (3), Nd (4), and Gd (5)) and [Ln(Hhqc)(ox)(H(2)O)(2)](n) (Ln = Eu (6), Tb (7), Sm (8), Tm (9), Dy (10), Nd (11), Yb (12), and Gd (13); H(2)ox = oxalic acid), have been synthesized under hydrothermal conditions. Complexes 1-5 are isomorphous, which can be described as a two-dimensional (2D) hxl/Shubnikov network based on Ln(2)(CO(2))(4) paddle-wheel units, and the isomorphous complexes 6-13 feature a 2D decker layer architecture constructed by Ln-ox infinite chains cross-linked alternatively by bridging Hhqc(-) ligands. The room-temperature photoluminescence spectra of complexes Eu(III) (1 and 6), Tb(III) (2 and 7), and Sm(III) (3 and 8) exhibit strong characteristic emissions in the visible region, whereas Nd(III) (4 and 11) and Yb(III) (12) complexes display NIR luminescence upon irradiation at the ligand band. Moreover, the triplet state of H(2)hqc matches well with the emission level of Eu(III), Tb(III), and Sm(III) ions, which allows the preparation of new optical materials with enhanced luminescence properties.

Molecular structure of leucine aminopeptidase at 2. 7- angstrom resolution

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

Burley, S.K.; David, P.R.; Lipscomb, W.N.

1990-09-01

The three-dimensional structure of bovine lens leucine aminopeptidase complexed with bestatin, a slow-binding inhibitor, has been solved to 3.0-{angstrom} resolution by the multiple isomorphous replacement method with phase combination and density modification. In addition, the structure of the isomorphous native enzyme has been refined at 2.7-{angstrom} resolution, and the current crystallographic R factor is 0.169 for a model that includes the two zinc ions and all 487 amino acid residues comprising the asymmetric unit. The enzyme is physiologically active as a hexamer, which has 32 symmetry and is triangular in shape with a triangle edge length of 115 {angstrom} andmore » maximal thickness of 90 {angstrom}. The monomers are crystallographically equivalent and each is folded into two unequal {alpha}/{beta} domains connected by an {alpha}-helix to give a comma-like shape with approximate maximal dimensions of 90 x 55 x 55 {angstrom}{sup 3}. The secondary structural composition is 40% {alpha}-helix and 19% {beta}-strand. The active site also contains two positively charged residues, Lys-250 and Arg-336. The six active sites are themselves located in the interior of the hexamer, where they line a disk-shaped cavity of radius 15 {angstrom} and thickness 10 {angstrom}. Access to this cavity is provided by solvent channels that run along the twofold symmetry axes.« less

A Series of Robust Copper-Based Triazolyl Isophthalate MOFs: Impact of Linker Functionalization on Gas Sorption and Catalytic Activity †

PubMed Central

Junghans, Ulrike; Kobalz, Merten; Erhart, Oliver; Preißler, Hannes; Lincke, Jörg; Möllmer, Jens; Krautscheid, Harald; Gläser, Roger

2017-01-01

The synthesis and characterization of an isomorphous series of copper-containing microporous metal-organic frameworks (MOFs) based on triazolyl isophthalate linkers with the general formula ∞3[Cu4(μ3-OH)2(R1-R2-trz-ia)3(H2O)x] are presented. Through size adjustment of the alkyl substituents R1 and/or R2 at the linker, the impact of linker functionalization on structure-property relationships was studied. Due to the arrangement of the substituents towards the cavities, the porosity (pore fraction 28%–39%), as well as the pore size can be adjusted by the size of the substituents of the triazole ring. Thermal analysis and temperature-dependent PXRD studies reveal a thermal stability of the MOFs up to 230 °C due to increasing framework stability through fine-tuning of the linker substitution pattern. Adsorption of CO2 (298 K) shows a decreasing maximum loading with increasing steric demand of the substituents of the triazole ring. Furthermore, the selective oxidation of cyclohexene with tert-butyl hydroperoxide (TBHP) is studied over the MOFs at 323 K in liquid chloroform. The catalytic activity increases with the steric demand of the substituents. Additionally, these isomorphous MOFs exhibit considerable robustness under oxidizing conditions confirmed by CO2 adsorption studies, as well as by the catalytic selective oxidation experiments. PMID:28772698

Some cycle-supermagic labelings of the calendula graphs

NASA Astrophysics Data System (ADS)

Pradipta, T. R.; Salman, A. N. M.

2018-01-01

In this paper, we introduce a calendula graph, denoted by Clm,n . It is a graph constructed from a cycle on m vertices Cm and m copies of Cn which are Cn1 , Cn2 , ⋯, Cnm and grafting the i-th edge of Cm to an edge of in Cni for each i ∈ {1,2,⋯,m}. A graph G = (V, E) admits a Cn -covering, if every edge e ∈ E(G) belongs to a subgraph of G isomorphic to Cn . The graph G is called cycle-magic, if there exists a total labeling ϕ: V ∪ E → {1,2,…,|V|+|E|} such that for every subgraph Cn ‧ = (V‧,E‧) of G isomorphic to Cn has the same weight. In this case, the weight of Cn , denoted by ϕ(Cn ’), is defined as ∑ v∈V(C’n ) ϕ(v) + ∑ e∈E(C’n ) ϕ(e). Furthermore, G is called cycle-supermagic, if ϕ:V→{1,2,…,|V|}. In this paper, we provide some cycle-supermagic labelings of calendula graphs. In order to prove it, we develop a technique, to make a partition of a multiset into m sub-multisets with the same cardinality such that the sum of all elements of each sub-multiset is same. The technique is called an m-balanced multiset.

Thermodynamic scaling of the shear viscosity of Mie n-6 fluids and their binary mixtures

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

Delage-Santacreu, Stephanie; Galliero, Guillaume, E-mail: guillaume.galliero@univ-pau.fr; Hoang, Hai

2015-05-07

In this work, we have evaluated the applicability of the so-called thermodynamic scaling and the isomorph frame to describe the shear viscosity of Mie n-6 fluids of varying repulsive exponents (n = 8, 12, 18, 24, and 36). Furthermore, the effectiveness of the thermodynamic scaling to deal with binary mixtures of Mie n-6 fluids has been explored as well. To generate the viscosity database of these fluids, extensive non-equilibrium molecular dynamics simulations have been performed for various thermodynamic conditions. Then, a systematic approach has been used to determine the gamma exponent value (γ) characteristic of the thermodynamic scaling approach formore » each system. In addition, the applicability of the isomorph theory with a density dependent gamma has been confirmed in pure fluids. In both pure fluids and mixtures, it has been found that the thermodynamic scaling with a constant gamma is sufficient to correlate the viscosity data on a large range of thermodynamic conditions covering liquid and supercritical states as long as the density is not too high. Interestingly, it has been obtained that, in pure fluids, the value of γ is directly proportional to the repulsive exponent of the Mie potential. Finally, it has been found that the value of γ in mixtures can be deduced from those of the pure component using a simple logarithmic mixing rule.« less

Effect of Isomorphous Substitution on the Thermal Decomposition Mechanism of Hydrotalcites

PubMed Central

Crosby, Sergio; Tran, Doanh; Cocke, David; Duraia, El-Shazly M.; Beall, Gary W.

2014-01-01

Hydrotalcites have many important applications in catalysis, wastewater treatment, gene delivery and polymer stabilization, all depending on preparation history and treatment scenarios. In catalysis and polymer stabilization, thermal decomposition is of great importance. Hydrotalcites form easily with atmospheric carbon dioxide and often interfere with the study of other anion containing systems, particularly if formed at room temperature. The dehydroxylation and decomposition of carbonate occurs simultaneously, making it difficult to distinguish the dehydroxylation mechanisms directly. To date, the majority of work on understanding the decomposition mechanism has utilized hydrotalcite precipitated at room temperature. In this study, evolved gas analysis combined with thermal analysis has been used to show that CO2 contamination is problematic in materials being formed at RT that are poorly crystalline. This has led to some dispute as to the nature of the dehydroxylation mechanism. In this paper, data for the thermal decomposition of the chloride form of hydrotalcite are reported. In addition, carbonate-free hydrotalcites have been synthesized with different charge densities and at different growth temperatures. This combination of parameters has allowed a better understanding of the mechanism of dehydroxylation and the role that isomorphous substitution plays in these mechanisms to be delineated. In addition, the effect of anion type on thermal stability is also reported. A stepwise dehydroxylation model is proposed that is mediated by the level of aluminum substitution. PMID:28788231

Algebraic reasoning and bat-and-ball problem variants: Solving isomorphic algebra first facilitates problem solving later.

PubMed

Hoover, Jerome D; Healy, Alice F

2017-12-01

The classic bat-and-ball problem is used widely to measure biased and correct reasoning in decision-making. University students overwhelmingly tend to provide the biased answer to this problem. To what extent might reasoners be led to modify their judgement, and, more specifically, is it possible to facilitate problem solution by prompting participants to consider the problem from an algebraic perspective? One hundred ninety-seven participants were recruited to investigate the effect of algebraic cueing as a debiasing strategy on variants of the bat-and-ball problem. Participants who were cued to consider the problem algebraically were significantly more likely to answer correctly relative to control participants. Most of this cueing effect was confined to a condition that required participants to solve isomorphic algebra equations corresponding to the structure of bat-and-ball question types. On a subsequent critical question with differing item and dollar amounts presented without a cue, participants were able to generalize the learned information to significantly reduce overall bias. Math anxiety was also found to be significantly related to bat-and-ball problem accuracy. These results suggest that, under specific conditions, algebraic reasoning is an effective debiasing strategy on bat-and-ball problem variants, and provide the first documented evidence for the influence of math anxiety on Cognitive Reflection Test performance.

Investigation of chemical vapour deposition diamond detectors by X-ray micro-beam induced current and X-ray micro-beam induced luminescence techniques

NASA Astrophysics Data System (ADS)

Olivero, P.; Manfredotti, C.; Vittone, E.; Fizzotti, F.; Paolini, C.; Lo Giudice, A.; Barrett, R.; Tucoulou, R.

2004-10-01

Tracking detectors have become an important ingredient in high-energy physics experiments. In order to survive the harsh detection environment of the large hadron collider (LHC), trackers need to have special properties. They must be radiation hard, provide fast collection of charge, be as thin as possible and remove heat from readout electronics. The unique properties of diamond allow it to fulfill these requirements. In this work we present an investigation of the charge transport and luminescence properties of "detector grade" artificial chemical vapour deposition (CVD) diamond devices developed within the CERN RD42 collaboration, performed by means of X-ray micro-beam induced current collection (XBICC) and X-ray micro-beam induced luminescence (XBIL) techniques. XBICC technique allows quantitative estimates of the transport parameters of the material to be evaluated and mapped with micrometric spatial resolution. In particular, the high resolution and sensitivity of the technique has allowed a quantitative study of the inhomogeneity of the charge transport parameter defined as the product of mobility and lifetime for both electron and holes. XBIL represents a technique complementary to ion beam induced luminescence (IBIL), which has already been used by our group, since X-ray energy loss profile in the material is different from that of MeV ions. X-ray induced luminescence maps have been performed simultaneously with induced photocurrent maps, to correlate charge transport and induced luminescence properties of diamond. Simultaneous XBICC and XBIL maps exhibit features of partial complementarity that have been interpreted on the basis of considerations on radiative and non-radiative recombination processes which compete with charge transport efficiency.

ShakeMap-based prediction of earthquake-induced mass movements in Switzerland calibrated on historical observations

USGS Publications Warehouse

Cauzzi, Carlo; Fah, Donat; Wald, David J.; Clinton, John; Losey, Stephane; Wiemer, Stefan

2018-01-01

In Switzerland, nearly all historical Mw ~ 6 earthquakes have induced damaging landslides, rockslides and snow avalanches that, in some cases, also resulted in damage to infrastructure and loss of lives. We describe the customisation to Swiss conditions of a globally calibrated statistical approach originally developed to rapidly assess earthquake-induced landslide likelihoods worldwide. The probability of occurrence of such earthquake-induced effects is modelled through a set of geospatial susceptibility proxies and peak ground acceleration. The predictive model is tuned to capture the observations from past events and optimised for near-real-time estimates based on USGS-style ShakeMaps routinely produced by the Swiss Seismological Service. Our emphasis is on the use of high-resolution geospatial datasets along with additional local information on ground failure susceptibility. Even if calibrated on historic events with moderate magnitudes, the methodology presented in this paper yields sensible results also for low-magnitude recent events. The model is integrated in the Swiss ShakeMap framework. This study has a high practical relevance to many Swiss ShakeMap stakeholders, especially those managing lifeline systems, and to other global users interested in conducting a similar customisation for their region of interest.

Probabilistic, Seismically-Induced Landslide Hazard Mapping of Western Oregon

NASA Astrophysics Data System (ADS)

Olsen, M. J.; Sharifi Mood, M.; Gillins, D. T.; Mahalingam, R.

2015-12-01

Earthquake-induced landslides can generate significant damage within urban communities by damaging structures, obstructing lifeline connection routes and utilities, generating various environmental impacts, and possibly resulting in loss of life. Reliable hazard and risk maps are important to assist agencies in efficiently allocating and managing limited resources to prepare for such events. This research presents a new methodology in order to communicate site-specific landslide hazard assessments in a large-scale, regional map. Implementation of the proposed methodology results in seismic-induced landslide hazard maps that depict the probabilities of exceeding landslide displacement thresholds (e.g. 0.1, 0.3, 1.0 and 10 meters). These maps integrate a variety of data sources including: recent landslide inventories, LIDAR and photogrammetric topographic data, geology map, mapped NEHRP site classifications based on available shear wave velocity data in each geologic unit, and USGS probabilistic seismic hazard curves. Soil strength estimates were obtained by evaluating slopes present along landslide scarps and deposits for major geologic units. Code was then developed to integrate these layers to perform a rigid, sliding block analysis to determine the amount and associated probabilities of displacement based on each bin of peak ground acceleration in the seismic hazard curve at each pixel. The methodology was applied to western Oregon, which contains weak, weathered, and often wet soils at steep slopes. Such conditions have a high landslide hazard even without seismic events. A series of landslide hazard maps highlighting the probabilities of exceeding the aforementioned thresholds were generated for the study area. These output maps were then utilized in a performance based design framework enabling them to be analyzed in conjunction with other hazards for fully probabilistic-based hazard evaluation and risk assessment. a) School of Civil and Construction Engineering, Oregon State University, Corvallis, OR 97331, USA

The Arabidopsis microtubule-associated protein MAP65-3 supports infection by filamentous biotrophic pathogens by down-regulating salicylic acid-dependent defenses.

PubMed

Quentin, Michaël; Baurès, Isabelle; Hoefle, Caroline; Caillaud, Marie-Cécile; Allasia, Valérie; Panabières, Franck; Abad, Pierre; Hückelhoven, Ralph; Keller, Harald; Favery, Bruno

2016-03-01

The oomycete Hyaloperonospora arabidopsidis and the ascomycete Erysiphe cruciferarum are obligate biotrophic pathogens causing downy mildew and powdery mildew, respectively, on Arabidopsis. Upon infection, the filamentous pathogens induce the formation of intracellular bulbous structures called haustoria, which are required for the biotrophic lifestyle. We previously showed that the microtubule-associated protein AtMAP65-3 plays a critical role in organizing cytoskeleton microtubule arrays during mitosis and cytokinesis. This renders the protein essential for the development of giant cells, which are the feeding sites induced by root knot nematodes. Here, we show that AtMAP65-3 expression is also induced in leaves upon infection by the downy mildew oomycete and the powdery mildew fungus. Loss of AtMAP65-3 function in the map65-3 mutant dramatically reduced infection by both pathogens, predominantly at the stages of leaf penetration. Whole-transcriptome analysis showed an over-represented, constitutive activation of genes involved in salicylic acid (SA) biosynthesis, signaling, and defense execution in map65-3, whereas jasmonic acid (JA)-mediated signaling was down-regulated. Preventing SA synthesis and accumulation in map65-3 rescued plant susceptibility to pathogens, but not the developmental phenotype caused by cytoskeleton defaults. AtMAP65-3 thus has a dual role. It positively regulates cytokinesis, thus plant growth and development, and negatively interferes with plant defense against filamentous biotrophs. Our data suggest that downy mildew and powdery mildew stimulate AtMAP65-3 expression to down-regulate SA signaling for infection. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Mapping the absolute magnetic field and evaluating the quadratic Zeeman-effect-induced systematic error in an atom interferometer gravimeter

NASA Astrophysics Data System (ADS)

Hu, Qing-Qing; Freier, Christian; Leykauf, Bastian; Schkolnik, Vladimir; Yang, Jun; Krutzik, Markus; Peters, Achim

2017-09-01

Precisely evaluating the systematic error induced by the quadratic Zeeman effect is important for developing atom interferometer gravimeters aiming at an accuracy in the μ Gal regime (1 μ Gal =10-8m /s2 ≈10-9g ). This paper reports on the experimental investigation of Raman spectroscopy-based magnetic field measurements and the evaluation of the systematic error in the gravimetric atom interferometer (GAIN) due to quadratic Zeeman effect. We discuss Raman duration and frequency step-size-dependent magnetic field measurement uncertainty, present vector light shift and tensor light shift induced magnetic field measurement offset, and map the absolute magnetic field inside the interferometer chamber of GAIN with an uncertainty of 0.72 nT and a spatial resolution of 12.8 mm. We evaluate the quadratic Zeeman-effect-induced gravity measurement error in GAIN as 2.04 μ Gal . The methods shown in this paper are important for precisely mapping the absolute magnetic field in vacuum and reducing the quadratic Zeeman-effect-induced systematic error in Raman transition-based precision measurements, such as atomic interferometer gravimeters.

MAP4 Mechanism that Stabilizes Mitochondrial Permeability Transition in Hypoxia: Microtubule Enhancement and DYNLT1 Interaction with VDAC1

PubMed Central

Zhang, Yi-ming; Zhang, Jia-ping; Hu, Jiong-yu; Zhang, Qiong; Dai, Xia; Teng, Miao; Zhang, Dong-xia; Huang, Yue-sheng

2011-01-01

Mitochondrial membrane permeability has received considerable attention recently because of its key role in apoptosis and necrosis induced by physiological events such as hypoxia. The manner in which mitochondria interact with other molecules to regulate mitochondrial permeability and cell destiny remains elusive. Previously we verified that hypoxia-induced phosphorylation of microtubule-associated protein 4 (MAP4) could lead to microtubules (MTs) disruption. In this study, we established the hypoxic (1% O2) cell models of rat cardiomyocytes, H9c2 and HeLa cells to further test MAP4 function. We demonstrated that increase in the pool of MAP4 could promote the stabilization of MT networks by increasing the synthesis and polymerization of tubulin in hypoxia. Results showed MAP4 overexpression could enhance cell viability and ATP content under hypoxic conditions. Subsequently we employed a yeast two-hybrid system to tag a protein interacting with mitochondria, dynein light chain Tctex-type 1 (DYNLT1), by hVDAC1 bait. We confirmed that DYNLT1 had protein-protein interactions with voltage-dependent anion channel 1 (VDAC1) using co-immunoprecipitation; and immunofluorescence technique showed that DYNLT1 was closely associated with MTs and VDAC1. Furthermore, DYNLT1 interactions with MAP4 were explored using a knockdown technique. We thus propose two possible mechanisms triggered by MAP4: (1) stabilization of MT networks, (2) DYNLT1 modulation, which is connected with VDAC1, and inhibition of hypoxia-induced mitochondrial permeabilization. PMID:22164227

Trace metal mapping by laser-induced breakdown spectroscopy

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

Kaiser, Jozef; Novotny, Dr. Karel; Hrdlicka, A

2012-01-01

Abstract: Laser-Induced Breakdown Spectroscopy (LIBS) is a sensitive optical technique capable of fast multi-elemental analysis of solid, gaseous and liquid samples. The potential applications of lasers for spectrochemical analysis were developed shortly after its invention; however the massive development of LIBS is connected with the availability of powerful pulsed laser sources. Since the late 80s of 20th century LIBS dominated the analytical atomic spectroscopy scene and its application are developed continuously. Here we review the utilization of LIBS for trace elements mapping in different matrices. The main emphasis is on trace metal mapping in biological samples.

CD4 T Cell Dependent Colitis Exacerbation Following Re-Exposure of Mycobacterium avium ssp. paratuberculosis.

PubMed

Suwandi, Abdulhadi; Bargen, Imke; Pils, Marina C; Krey, Martina; Zur Lage, Susanne; Singh, Anurag K; Basler, Tina; Falk, Christine S; Seidler, Ursula; Hornef, Mathias W; Goethe, Ralph; Weiss, Siegfried

2017-01-01

Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of Johne's disease (JD), a chronic inflammatory bowel disease of cattle characterized by intermittent to chronic diarrhea. In addition, MAP has been isolated from Crohn's disease (CD) patients. The impact of MAP on severity of clinical symptoms in JD as well as its role in CD are yet unknown. We have previously shown that MAP is able to colonize inflamed enteric tissue and to exacerbate the inflammatory tissue response (Suwandi et al., 2014). In the present study, we analyzed how repeated MAP administration influences the course of dextran sulfate sodium (DSS)-induced colitis. In comparison to mice exposed to DSS or MAP only, repeated exposure of DSS-treated mice to MAP (DSS/MAP) revealed a significantly enhanced clinical score, reduction of colon length as well as severe CD4 + T cell infiltration into the colonic lamina propria . Functional analysis identified a critical role of CD4 + T cells in the MAP-induced disease exacerbation. Additionally, altered immune responses were observed when closely related mycobacteria species such as M. avium ssp. avium and M. avium ssp. hominissuis were administered. These data reveal the specific ability of MAP to aggravate intestinal inflammation and clinical symptoms. Overall, this phenotype is compatible with similar disease promoting capabilites of MAP in JD and CD.

CD4 T Cell Dependent Colitis Exacerbation Following Re-Exposure of Mycobacterium avium ssp. paratuberculosis

PubMed Central

Suwandi, Abdulhadi; Bargen, Imke; Pils, Marina C.; Krey, Martina; Zur Lage, Susanne; Singh, Anurag K.; Basler, Tina; Falk, Christine S.; Seidler, Ursula; Hornef, Mathias W.; Goethe, Ralph; Weiss, Siegfried

2017-01-01

Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of Johne's disease (JD), a chronic inflammatory bowel disease of cattle characterized by intermittent to chronic diarrhea. In addition, MAP has been isolated from Crohn's disease (CD) patients. The impact of MAP on severity of clinical symptoms in JD as well as its role in CD are yet unknown. We have previously shown that MAP is able to colonize inflamed enteric tissue and to exacerbate the inflammatory tissue response (Suwandi et al., 2014). In the present study, we analyzed how repeated MAP administration influences the course of dextran sulfate sodium (DSS)-induced colitis. In comparison to mice exposed to DSS or MAP only, repeated exposure of DSS-treated mice to MAP (DSS/MAP) revealed a significantly enhanced clinical score, reduction of colon length as well as severe CD4+ T cell infiltration into the colonic lamina propria. Functional analysis identified a critical role of CD4+ T cells in the MAP-induced disease exacerbation. Additionally, altered immune responses were observed when closely related mycobacteria species such as M. avium ssp. avium and M. avium ssp. hominissuis were administered. These data reveal the specific ability of MAP to aggravate intestinal inflammation and clinical symptoms. Overall, this phenotype is compatible with similar disease promoting capabilites of MAP in JD and CD. PMID:28361039

Mechanisms underlying the biphasic effect of vitamin K1 (phylloquinone) on arterial blood pressure.

PubMed

Tirapelli, Carlos R; Resstel, Leonardo B M; de Oliveira, Ana M; Corrêa, Fernando M A

2008-07-01

Phylloquinone (vitamin K(1), VK(1)) is widely used therapeutically and intravenous administration of this quinone can induce hypotension. We aimed to investigate the mechanisms underlying the effects induced by VK(1) on arterial blood pressure. With this purpose a catheter was inserted into the abdominal aorta of male Wistar rats for blood pressure and heart rate recording. Bolus intravenous injection of VK(1) (0.5-20 mgkg(-1)) produced a transient increase in blood pressure followed by a fall. Both the pressor and depressor response induced by VK(1) were dose-dependent. On the other hand, intravenous injection of VK(1) did not alter heart rate. The nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 10 and 20 mgkg(-1)) reduced both the increase and decrease in blood pressure induced by VK(1) (5 mgkg(-1)). On the other hand, indometacin (10 mg kg(-1)), a non-selective cyclooxygenase inhibitor, did not alter the increase in mean arterial pressure (MAP) induced by VK(1). However, VK(1)-induced fall in MAP was significantly attenuated by indometacin. We concluded that VK(1) induces a dose-dependent effect on blood pressure that consists of an acute increase followed by a more sustained decrease in MAP. The hypotension induced by VK(1) involves the activation of the nitric oxide (NO) pathway and the release of vasodilator prostanoid(s).

Communication: Simple liquids' high-density viscosity

NASA Astrophysics Data System (ADS)

Costigliola, Lorenzo; Pedersen, Ulf R.; Heyes, David M.; Schrøder, Thomas B.; Dyre, Jeppe C.

2018-02-01

This paper argues that the viscosity of simple fluids at densities above that of the triple point is a specific function of temperature relative to the freezing temperature at the density in question. The proposed viscosity expression, which is arrived at in part by reference to the isomorph theory of systems with hidden scale invariance, describes computer simulations of the Lennard-Jones system as well as argon and methane experimental data and simulation results for an effective-pair-potential model of liquid sodium.

Linking entanglement and discrete anomaly

NASA Astrophysics Data System (ADS)

Hung, Ling-Yan; Wu, Yong-Shi; Zhou, Yang

2018-05-01

In 3 d Chern-Simons theory, there is a discrete one-form symmetry, whose symmetry group is isomorphic to the center of the gauge group. We study the `t Hooft anomaly associated to this discrete one-form symmetry in theories with generic gauge groups, A, B, C, D-types. We propose to detect the discrete anomaly by computing the Hopf state entanglement in the subspace spanned by the symmetry generators and develop a systematical way based on the truncated modular S matrix. We check our proposal for many examples.

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

Osipov, D V

We prove noncommutative reciprocity laws on an algebraic surface defined over a perfect field. These reciprocity laws establish that some central extensions of globally constructed groups split over certain subgroups constructed by points or projective curves on a surface. For a two-dimensional local field with a last finite residue field, the local central extension which is constructed is isomorphic to the central extension which comes from the case of tame ramification of the Abelian two-dimensional local Langlands correspondence suggested by Kapranov. Bibliography: 9 titles.

Resolution of a Rank-Deficient Adjustment Model Via an Isomorphic Geometrical Setup with Tensor Structure.

DTIC Science & Technology

1987-03-01

would be transcribed as L =AX - V where L, X, and V are the vectors of constant terms, parametric corrections , and b_o bresiduals, respectively. The...tensor. a Just as du’ represents the parametric corrections in tensor notations, the necessary associated metric tensor a’ corresponds to the variance...observations, n residuals, and 0 n- parametric corrections to X (an initial set of parameters), respectively. b 0 b The vctor L is formed as 1. L where

Influence of dopant substitution mechanism on catalytic properties within hierarchical architectures

PubMed Central

Newland, Stephanie H.; Sinkler, Wharton; Mezza, Thomas; Bare, Simon R.

2016-01-01

A range of hierarchically porous (HP) AlPO-5 catalysts, with isomorphously substituted transition metal ions, have been synthesized using an organosilane as a soft template. By employing a range of structural and spectroscopic characterization protocols, the properties of the dopant-substituted species within the HP architectures have been carefully evaluated. The resulting nature of the active site is shown to have a direct impact on the ensuing catalytic properties in the liquid-phase Beckmann rearrangement of cyclic ketones. PMID:27493563

On Non-Abelian Extensions of 3-Lie Algebras

NASA Astrophysics Data System (ADS)

Song, Li-Na; Makhlouf, Abdenacer; Tang, Rong

2018-04-01

In this paper, we study non-abelian extensions of 3-Lie algebras through Maurer-Cartan elements. We show that there is a one-to-one correspondence between isomorphism classes of non-abelian extensions of 3-Lie algebras and equivalence classes of Maurer-Cartan elements in a DGLA. The structure of the Leibniz algebra on the space of fundamental objects is also analyzed. Supported by National Natural Science Foundation of China under Grant No. 11471139 and National Natural Science Foundation of Jilin Province under Grant No. 20170101050JC

Array architectures for iterative algorithms

NASA Technical Reports Server (NTRS)

Jagadish, Hosagrahar V.; Rao, Sailesh K.; Kailath, Thomas

1987-01-01

Regular mesh-connected arrays are shown to be isomorphic to a class of so-called regular iterative algorithms. For a wide variety of problems it is shown how to obtain appropriate iterative algorithms and then how to translate these algorithms into arrays in a systematic fashion. Several 'systolic' arrays presented in the literature are shown to be specific cases of the variety of architectures that can be derived by the techniques presented here. These include arrays for Fourier Transform, Matrix Multiplication, and Sorting.

Quiver W-algebras

NASA Astrophysics Data System (ADS)

Kimura, Taro; Pestun, Vasily

2018-06-01

For a quiver with weighted arrows, we define gauge-theory K-theoretic W-algebra generalizing the definition of Shiraishi et al. and Frenkel and Reshetikhin. In particular, we show that the qq-character construction of gauge theory presented by Nekrasov is isomorphic to the definition of the W-algebra in the operator formalism as a commutant of screening charges in the free field representation. Besides, we allow arbitrary quiver and expect interesting applications to representation theory of generalized Borcherds-Kac-Moody Lie algebras, their quantum affinizations and associated W-algebras.

Lusztig symmetries and Poincare-Birkhoff-Witt basis for wU{sub r,s}{sup d}(osp(1|2n))

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

Liu, Junli; College of Applied Sciences, Beijing University of Technology, Beijing 100124; Yang, Shilin

2013-12-15

We investigate a new kind of two-parameter weak quantized superalgebra wU{sub r,s}{sup d}(osp(1|2n)), which is a weak Hopf superalgebra. It has a homomorphic image which is isomorphic to the usual two-parameter quantum superalgebra U{sub r,s}(osp(1|2n)) of osp(1|2n). We also discuss the basis of wU{sub r,s}{sup d}(osp(1|2n)) by Lusztig's symmetries.

North American Jumelage ’Type Systems’

DTIC Science & Technology

1993-10-20

Brian Howard bhoward~saul.cis.upenn.edu Doug Howe howegcs.cornell.edu Paul Jackson jacksongcs.cornell.edu Radhakrishnan Jagadeesan rj2Gdoc.imperial.ac.uk...Curry and Howard . They have shown that there exists an ’’isomorphism’’ between the terms of typed lambda calculus and the natural deduction proofs of...linear logic for computer science 3:05-3:30 Break 3:30-4:00 G. Bellin , Oxford University: Proof-nets without boxes and graphs with orientations 4:05-4:25 H

Cocrystals and alloys of nitazoxanide: enhanced pharmacokinetics.

PubMed

Suresh, Kuthuru; Mannava, M K Chaitanya; Nangia, Ashwini

2016-03-18

Two isomorphous cocrystals of nitazoxanide (NTZ) with p-aminosalicylic acid (PASA) and p-aminobenzoic acid (PABA) as well as their alloys were prepared by slurry and grinding techniques. The cocrystals exhibit faster dissolution rates and higher pharmacokinetic properties compared to the reference drug, and surprisingly the cocrystal alloy NTZ-PABA : NTZ-PASA (0.75 : 0.25) exhibited 4 fold higher bioavailability of NTZ in Sprague Dawley rats. This study opens the opportunity for cocrystal alloys as improved medicines.

Influence of dopant substitution mechanism on catalytic properties within hierarchical architectures

NASA Astrophysics Data System (ADS)

Newland, Stephanie H.; Sinkler, Wharton; Mezza, Thomas; Bare, Simon R.; Raja, Robert

2016-07-01

A range of hierarchically porous (HP) AlPO-5 catalysts, with isomorphously substituted transition metal ions, have been synthesized using an organosilane as a soft template. By employing a range of structural and spectroscopic characterization protocols, the properties of the dopant-substituted species within the HP architectures have been carefully evaluated. The resulting nature of the active site is shown to have a direct impact on the ensuing catalytic properties in the liquid-phase Beckmann rearrangement of cyclic ketones.

Higher T-duality in M-theory via local supersymmetry

NASA Astrophysics Data System (ADS)

Sati, Hisham; Schreiber, Urs

2018-06-01

By analyzing super-torsion and brane super-cocycles, we derive a new duality in M-theory, which takes the form of a higher version of T-duality in string theory. This involves a new topology change mechanism abelianizing the 3-sphere associated with the C-field topology to the 517-torus associated with exceptional-generalized super-geometry. Finally we explain parity symmetry in M-theory within exceptional-generalized super-spacetime at the same level of spherical T-duality, namely as an isomorphism on 7-twisted cohomology.

Nonrashes. Part I: The Koebner nonreaction

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

Bernhard, J.D.; Haynes, H.A.

1982-02-01

''Nonrashes'' range from pruritus that may signal an underlying systemic illness to delusional parasitosis associated with severe psychological disturbance. We report another kind of nonrash, the Koebner nonreaction or isomorphic nonresponse, that was manifested by the absence of a drug rash at the site of recently administered x-irradiation. We also present a compilation of a number of other nonrashes, such as the mitempfindungen (referred itch) and the prodrome of herpes zoster. The recognition of certain types of nonrashes may be lifesaving.

Bialgebra deformations and algebras of trees

NASA Technical Reports Server (NTRS)

Grossman, Robert; Radford, David

1991-01-01

Let A denote a bialgebra over a field k and let A sub t = A((t)) denote the ring of formal power series with coefficients in A. Assume that A is also isomorphic to a free, associative algebra over k. A simple construction is given which makes A sub t a bialgebra deformation of A. In typical applications, A sub t is neither commutative nor cocommutative. In the terminology of Drinfeld, (1987), A sub t is a quantum group. This construction yields quantum groups associated with families of trees.

Differential Calculus on h-Deformed Spaces

NASA Astrophysics Data System (ADS)

Herlemont, Basile; Ogievetsky, Oleg

2017-10-01

We construct the rings of generalized differential operators on the h-deformed vector space of gl-type. In contrast to the q-deformed vector space, where the ring of differential operators is unique up to an isomorphism, the general ring of h-deformed differential operators {Diff}_{h},σ(n) is labeled by a rational function σ in n variables, satisfying an over-determined system of finite-difference equations. We obtain the general solution of the system and describe some properties of the rings {Diff}_{h},σ(n).

Nonlinear Properties in Langasite Isomorphs for Advanced Frequency Control Devices and Clocks

DTIC Science & Technology

2006-11-01

or LGN), and langatate (La3Ga5.5Ta0.5O14 or LGT), have emerged as new materials to replace quartz in advanced frequency control devices and clocks...application and of angle Ψ. Fig. 1. Langatate boule (photo courtesy of the Univ. Central Florida) and typical resonators for testing. Table 1...langanite and y-cut langatate ,” IEEE Tr. Ultrason. Ferroelec. Freq. Contr., pp. 1678-1682, 2003. Kim, Y., “Amplitude-frequency effect of Y-cut langanite

The Crystal Structure of Thorium and Zirconium Dihydrides by X-ray and Neutron Diffraction

DOE R&D Accomplishments Database

Rundle, R.E.; Shull, C.G.; Wollan, E.O.

1951-04-20

Thorium forms a tetragonal lower hydride of composition ThH{sub 2}. The hydrides ThH{sub 2}, ThD{sub 2}, and ZrD{sub 2} have been studied by neutron diffraction in order that hydrogen positions could be determined. The hydrides are isomorphous, and have a deformed fluorite structure. Metal-hydrogen distances in thorium hydride are unusually large, as in UH{sub 3}. Thorium and zirconium scattering amplitudes and a revised scattering amplitude for deuterium are reported.

Brain redox imaging in the pentylenetetrazole (PTZ)-induced kindling model of epilepsy by using in vivo electron paramagnetic resonance and a nitroxide imaging probe.

PubMed

Emoto, Miho C; Yamato, Mayumi; Sato-Akaba, Hideo; Yamada, Ken-ichi; Fujii, Hirotada G

2015-11-03

Much evidence supports the idea that oxidative stress is involved in the pathogenesis of epilepsy, and therapeutic interventions with antioxidants are expected as adjunct antiepileptic therapy. The aims of this study were to non-invasively obtain spatially resolved redox data from control and pentylenetetrazole (PTZ)-induced kindled mouse brains by electron paramagnetic resonance (EPR) imaging and to visualize the brain regions that are sensitive to oxidative damage. After infusion of the redox-sensitive imaging probe 3-methoxycarbonyl-2,2,5,5-tetramethyl-piperidine-1-oxyl (MCP), a series of EPR images of PTZ-induced mouse heads were measured. Based on the pharmacokinetics of the reduction reaction of MCP in the mouse heads, the pixel-based rate constant of its reduction reaction was calculated as an index of redox status in vivo and mapped as a redox map. The obtained redox map showed heterogeneity in the redox status in PTZ-induced mouse brains compared with control. The co-registered image of the redox map and magnetic resonance imaging (MRI) for both control and PTZ-induced mice showed a clear change in the redox status around the hippocampus after PTZ. To examine the role of antioxidants on the brain redox status, the levels of antioxidants were measured in brain tissues of control and PTZ-induced mice. Significantly lower concentrations of glutathione in the hippocampus of PTZ-kindled mice were detected compared with control. From the results of both EPR imaging and the biochemical assay, the hippocampus was found to be susceptible to oxidative damage in the PTZ-induced animal model of epilepsy. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

What is a Question?

NASA Technical Reports Server (NTRS)

Knuth, Kevin H.; Clancy, Daniel (Technical Monitor)

2002-01-01

A given question can be defined in terms of the set of statements or assertions that answer it. Application of the logic of inference to this set of assertions allows one to derive the logic of inquiry among questions. There are interesting symmetries between the logics of inference and inquiry; where probability describes the degree to which a premise implies an assertion, there exists an analogous quantity that describes the bearing or relevance that a question has on an outstanding issue. These have been extended to suggest that the logic of inquiry results in functional relationships analogous to, although more general than, those found in information theory. Employing lattice theory, I examine in greater detail the structure of the space of assertions and questions demonstrating that the symmetries between the logical relations in each of the spaces derive directly from the lattice structure. Furthermore, I show that while symmetries between the spaces exist, the two lattices are not isomorphic. The lattice of assertions is described by a Boolean lattice 2(sup N) whereas the lattice of real questions is shown to be a sublattice of the free distributive lattice FD(N) = 2(sup 2(sup N)). Thus there does not exist a one-to-one mapping of assertions to questions, there is no reflection symmetry between the two spaces, and questions in general do not possess unique complements. Last, with these lattice structures in mind, I discuss the relationship between probability, relevance and entropy.

Direct Images, Fields of Hilbert Spaces, and Geometric Quantization

NASA Astrophysics Data System (ADS)

Lempert, László; Szőke, Róbert

2014-04-01

Geometric quantization often produces not one Hilbert space to represent the quantum states of a classical system but a whole family H s of Hilbert spaces, and the question arises if the spaces H s are canonically isomorphic. Axelrod et al. (J. Diff. Geo. 33:787-902, 1991) and Hitchin (Commun. Math. Phys. 131:347-380, 1990) suggest viewing H s as fibers of a Hilbert bundle H, introduce a connection on H, and use parallel transport to identify different fibers. Here we explore to what extent this can be done. First we introduce the notion of smooth and analytic fields of Hilbert spaces, and prove that if an analytic field over a simply connected base is flat, then it corresponds to a Hermitian Hilbert bundle with a flat connection and path independent parallel transport. Second we address a general direct image problem in complex geometry: pushing forward a Hermitian holomorphic vector bundle along a non-proper map . We give criteria for the direct image to be a smooth field of Hilbert spaces. Third we consider quantizing an analytic Riemannian manifold M by endowing TM with the family of adapted Kähler structures from Lempert and Szőke (Bull. Lond. Math. Soc. 44:367-374, 2012). This leads to a direct image problem. When M is homogeneous, we prove the direct image is an analytic field of Hilbert spaces. For certain such M—but not all—the direct image is even flat; which means that in those cases quantization is unique.

Model of Four-Dimensional Sub-Proton Euclidean Space with Real Time for Valence Quarks. Lagrangian Mechanics

NASA Astrophysics Data System (ADS)

Kreymer, E. L.

2018-06-01

The model of Euclidean space with imaginary time used in sub-hadron physics uses only part of it since this part is isomorphic to Minkowski space and has the velocity limit 0 ≤ ||v Ei|| ≤ 1. The model of four-dimensional Euclidean space with real time (E space), in which 0 ≤ ||v E|| ≤ ∞ is investigated. The vectors of this space have E-invariants, equal or analogous to the invariants of Minkowski space. All relations between physical quantities in E-space, after they are mapped into Minkowski space, satisfy the principles of SRT and are Lorentz-invariant, and the velocity of light corresponds to infinite velocity. Results obtained in the model are different from the physical laws in Minkowski space. Thus, from the model of the Lagrangian mechanics of quarks in a centrally symmetric attractive potential it follows that the energy-mass of a quark decreases with increase of the velocity and is equal to zero for v = ∞. This made it possible to establish the conditions of emission and absorption of gluons by quarks. The effect of emission of gluons by high-energy quarks was discovered experimentally significantly earlier. The model describes for the first time the dynamic coupling of the masses of constituent and current quarks and reveals new possibilities in the study of intrahardon space. The classical trajectory of the oscillation of quarks in protons is described.

Cyanidin-3-glucoside inhibits UVB-induced oxidative damage and inflammation by regulating MAP kinase and NF-κB signaling pathways in SKH-1 hairless mice skin

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

Pratheeshkumar, Poyil; Son, Young-Ok; Wang, Xin

Skin cancer is one of the most commonly diagnosed cancers in the United States. Exposure to ultraviolet-B (UVB) radiation induces inflammation and photocarcinogenesis in mammalian skin. Cyanidin-3-glucoside (C3G), a member of the anthocyanin family, is present in various vegetables and fruits especially in edible berries, and displays potent antioxidant and anticarcinogenic properties. In this study, we have assessed the in vivo effects of C3G on UVB irradiation induced chronic inflammatory responses in SKH-1 hairless mice, a well-established model for UVB-induced skin carcinogenesis. Here, we show that C3G inhibited UVB-induced skin damage and inflammation in SKH-1 hairless mice. Our results indicatemore » that C3G inhibited glutathione depletion, lipid peroxidation and myeloperoxidation in mouse skin by chronic UVB exposure. C3G significantly decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-6 and TNF-α, associated with cutaneous inflammation. Likewise, UVB-induced inflammatory responses were diminished by C3G as observed by a remarkable reduction in the levels of phosphorylated MAP kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, C3G also decreased UVB-induced cyclooxygenase-2 (COX-2), PGE{sub 2} and iNOS levels, which are well-known key mediators of inflammation and cancer. Treatment with C3G inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mice skin. Immunofluorescence assay revealed that topical application of C3G inhibited the expression of 8-hydroxy-2′-deoxyguanosine, proliferating cell nuclear antigen, and cyclin D1 in chronic UVB exposed mouse skin. Collectively, these data indicates that C3G can provide substantial protection against the adverse effects of UVB radiation by modulating UVB-induced MAP kinase and NF-κB signaling pathways. - Highlights: • C3G inhibited UVB-induced oxidative damage and inflammation. • C3G inhibited UVB-induced COX-2, iNOS and PGE{sub 2} production. • C3G inhibited UVB-induced elevated proinflammatory cytokine level. • C3G inhibited UVB-induced p38 MAP kinase signaling. • C3G inhibited UVB-induced NF-κB activation.« less

Deletion Mapping of zwf, the Gene for a Constitutive Enzyme, Glucose 6-Phosphate Dehydrogenase in ESCHERICHIA COLI

PubMed Central

Fraenkel, D. G.; Banerjee, Santimoy

1972-01-01

Genes for three enzymes of intermediary sugar metabolism in E. coli, zwf (glucose 6-phosphate dehydrogenase, constitutive), edd (gluconate 6-phosphate dehydrase, inducible), and eda (2-keto-3-deoxygluconate 6-phosphate aldolase, differently inducible) are closely linked on the E. coli genetic map, the overall gene order being man... old... eda. edd. zwf... cheB... uvrC... his. One class of apparent revertants of an eda mutant strain contains a secondary mutation in edd, and some of these mutations are deletions extending into zwf. We have used a series of spontaneous edd-zwf deletions to map a series of point mutants in zwf and thus report the first fine structure map of a gene for a constitutive enzyme (zwf). PMID:4560065

Imaging interfacial electrical transport in graphene–MoS{sub 2} heterostructures with electron-beam-induced-currents

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

White, E. R., E-mail: ewhite@physics.ucla.edu; Kerelsky, Alexander; Hubbard, William A.

2015-11-30

Heterostructure devices with specific and extraordinary properties can be fabricated by stacking two-dimensional crystals. Cleanliness at the inter-crystal interfaces within a heterostructure is crucial for maximizing device performance. However, because these interfaces are buried, characterizing their impact on device function is challenging. Here, we show that electron-beam induced current (EBIC) mapping can be used to image interfacial contamination and to characterize the quality of buried heterostructure interfaces with nanometer-scale spatial resolution. We applied EBIC and photocurrent imaging to map photo-sensitive graphene-MoS{sub 2} heterostructures. The EBIC maps, together with concurrently acquired scanning transmission electron microscopy images, reveal how a device's photocurrentmore » collection efficiency is adversely affected by nanoscale debris invisible to optical-resolution photocurrent mapping.« less

Genome-wide ChIP-seq mapping and analysis of butyrate-induced H3K9 and H3K27 acetylation and epigenomic landscape alteration in bovine cells

USDA-ARS?s Scientific Manuscript database

Utilizing next-generation sequencing technology, combined with ChIP (Chromatin Immunoprecipitation) technology, we analyzed histone modification (acetylation) induced by butyrate and the large-scale mapping of the epigenomic landscape of normal histone H3 and acetylated histone H3K9 and H3K27. To d...

Effects of prostaglandin F(2alpha)and carbachol on MAP kinases, cytosolic phospholipase A(2)and arachidonic acid release in cat iris sphincter smooth muscle cells.

PubMed

Husain, S; Abdel-Latif, A A

2001-05-01

The signal transduction pathways initiated by Ca(2+)-mobilizing agonists, such as prostaglandin F(2alpha)(PGF(2alpha)) and carbachol (CCh), leading to activation of cytosolic phospholipase A(2)(cPLA(2)) and arachidonic acid (AA) release in a wide variety of tissues remain obscure. To further define the role of protein kinases in receptor mediated stimulation of cPLA(2)and consequently AA release we have investigated the role of mitogen-activated protein (MAP) kinases and protein kinase C (PKC) in PGF(2alpha)- and CCh-induced cPLA(2)phosphorylation and AA release in cat iris sphincter smooth muscle (CISM) cells. The cells were prelabeled with [(3)H]AA for 24 hr and incubated in the absence or presence of the agonist for 5-10 min as indicated. MAP kinases activities and cPLA(2)phosphorylation were determined in immunoprecipitates obtained by using anti-p38 MAP kinase and anti-cPLA(2)antibodies. We found that: (a) PGF(2alpha)and CCh increased p38 MAP kinase activity by 197 and 215%, respectively, and increased p42/p44 MAP kinase activity by 200 and 125%, respectively. (b) SB202190, a p38 MAP kinase specific inhibitor, inhibited PGF(2alpha)- and CCh-induced cPLA(2)phosphorylation by 92 and 85%, respectively, and AA release by 62 and 78%, respectively. (c) PD98059, a p42/p44 MAP kinase inhibitor, inhibited CCh-induced cPLA(2)phosphorylation by 70% and AA release by 71%, but had no effect on that of PGF(2alpha). (d) Inhibition of PKC activity by RO 31-8220 inhibited both PGF(2alpha)- and CCh-stimulation of p38 MAP kinase, p42/p44 MAP kinases and cPLA(2)phosphorylation. We conclude from these results that in CISM cells PGF(2alpha)-induced cPLA(2)phosphorylation and AA release is mediated through p38 MAP kinase, but not through p42/p44 MAP kinases, whereas that of CCh is mediated through both p38 MAP kinase and p42/p44 MAP kinases. These effects of PGF(2alpha)and CCh are regulated by the MAP kinases in a PKC-dependent manner. Studies aimed at elucidating the role of protein kinases in the coupling mechanism between the activation of PGF(2alpha)and muscarinic receptors, and the stimulation of cPLA(2)and AA release in the smooth muscles of the iris-ciliary body will provide important information about the role of protein kinases signaling pathways in smooth muscle function, as well as about the mechanism of the intraocular pressure-lowering effects of PGF(2alpha)and its analog, latanoprost, in glaucoma therapy. Copyright 2001 Academic Press.

Submicron mapping of strained silicon-on-insulator features induced

NASA Astrophysics Data System (ADS)

Murray, Conal E.; Sankarapandian, M.; Polvino, S. M.; Noyan, I. C.; Lai, B.; Cai, Z.

2007-04-01

Real-space maps of strain within silicon-on-insulator (SOI) features induced by adjacent, embedded shallow-trench-isolation (STI) SiO2 regions were obtained using x-ray microbeam diffraction. The quantitative strain mapping indicated that the SOI strain was largest at the SOI/STI interface and decreased as a function of distance from this interface. An out-of-plane residual strain of approximately -31μɛ was observed in the blanket regions of the SOI. A comparison of the depth-averaged strain distributions to the strain profiles calculated from an Eshelby inclusion model indicated an equivalent eigenstrain of -0.55% in the STI regions acting on the SOI features.

Staufen 2 regulates mGluR long-term depression and Map1b mRNA distribution in hippocampal neurons.

PubMed

Lebeau, Geneviève; Miller, Linda C; Tartas, Maylis; McAdam, Robyn; Laplante, Isabel; Badeaux, Frédérique; DesGroseillers, Luc; Sossin, Wayne S; Lacaille, Jean-Claude

2011-01-01

The two members of the Staufen family of RNA-binding proteins, Stau1 and Stau2, are present in distinct ribonucleoprotein complexes and associate with different mRNAs. Stau1 is required for protein synthesis-dependent long-term potentiation (L-LTP) in hippocampal pyramidal cells. However, the role of Stau2 in synaptic plasticity remains unexplored. We found that unlike Stau1, Stau2 is not required for L-LTP. In contrast, Stau2, but not Stau1, is necessary for DHPG-induced protein synthesis-dependent long-term depression (mGluR-LTD). While Stau2 is involved in early development of spines, its down-regulation does not alter spine morphology or spontaneous miniature synaptic activity in older cultures where LTD occurs. In addition, Stau2, but not Stau1, knockdown reduces the dendritic localization of Map1b mRNA, a specific transcript involved in mGluR-LTD. Moreover, mGluR stimulation with DHPG induces Map1b, but not Map2, mRNA dissociation from mRNA granules containing Stau2 and the ribosomal protein P0. This dissociation was not observed in cells in which Stau2 was depleted. Finally, Stau2 knockdown reduces basal Map1b protein expression in dendrites and prevents DHPG-induced increases in dendritic Map1b protein level. We suggest a role for Stau2 in the generation and regulation of Map1b mRNA containing granules that are required for mGluR-LTD.

Quantitative assessment of biliary stent artifacts on MR images: Potential implications for target delineation in radiotherapy.

PubMed

Gurney-Champion, Oliver J; Bruins Slot, Thijs; Lens, Eelco; van der Horst, Astrid; Klaassen, Remy; van Laarhoven, Hanneke W M; van Tienhoven, Geertjan; van Hooft, Jeanin E; Nederveen, Aart J; Bel, Arjan

2016-10-01

Biliary stents may cause susceptibility artifacts, gradient-induced artifacts, and radio frequency (RF) induced artifacts on magnetic resonance images, which can hinder accurate target volume delineation in radiotherapy. In this study, the authors investigated and quantified the magnitude of these artifacts for stents of different materials. Eight biliary stents made of nitinol, platinum-cored nitinol, stainless steel, or polyethylene from seven vendors, with different lengths (57-98 mm) and diameters (3.0-11.7 mm), were placed in a phantom. To quantify the susceptibility artifacts sequence-independently, ΔB0-maps and T2 ∗ -maps were acquired at 1.5 and 3 T. To study the effect of the gradient-induced artifacts at 3 T, signal decay in images obtained with maximum readout gradient-induced artifacts was compared to signal decay in reference scans. To quantify the RF induced artifacts at 3 T, B1-maps were acquired. Finally, ΔB0-maps and T2 ∗ -maps were acquired at 3 T of two pancreatic cancer patients who had received platinum-cored nitinol biliary stents. Outside the stent, susceptibility artifacts dominated the other artifacts. The stainless steel stent produced the largest susceptibility artifacts. The other stents caused decreased T2 ∗ up to 5.1 mm (1.5 T) and 8.5 mm (3 T) from the edge of the stent. For sequences with a higher bandwidth per voxel (1.5 T: BW vox > 275 Hz/voxel; 3 T: BW vox > 500 Hz/voxel), the B0-related susceptibility artifacts were negligible (<0.2 voxels). The polyethylene stent showed no artifacts. In vivo, the changes in B0 and T2 ∗ induced by the stent were larger than typical variations in B0 and T2 ∗ induced by anatomy when the stent was at an angle of 30° with the main magnetic field. Susceptibility artifacts were dominating over the other artifacts. The magnitudes of the susceptibility artifacts were determined sequence-independently. This method allows to include additional safety margins that ensure target irradiation.

Calcium Hydroxide-induced Proliferation, Migration, Osteogenic Differentiation, and Mineralization via the Mitogen-activated Protein Kinase Pathway in Human Dental Pulp Stem Cells.

PubMed

Chen, Luoping; Zheng, Lisha; Jiang, Jingyi; Gui, Jinpeng; Zhang, Lingyu; Huang, Yan; Chen, Xiaofang; Ji, Jing; Fan, Yubo

2016-09-01

Calcium hydroxide has been extensively used as the gold standard for direct pulp capping in clinical dentistry. It induces proliferation, migration, and mineralization in dental pulp stem cells (DPSCs), but the underlying mechanisms are still unclear. The aim of this study was to investigate the role of the mitogen-activated protein (MAP) kinase pathway in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Human DPSCs between passages 3 and 6 were used. DPSCs were preincubated with inhibitors of MAP kinases and cultured with calcium hydroxide. The phosphorylated MAP kinases were detected by Western blot analysis. Cell viability was analyzed via the methylthiazol tetrazolium assay. Cell migration was estimated using the wound healing assay. Alkaline phosphatase (ALP) expression was analyzed using the ALP staining assay. Mineralization was studied by alizarin red staining analysis. Calcium hydroxide significantly promoted the phosphorylation of the c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase. The inhibition of JNK and p38 signaling abolished calcium hydroxide-induced proliferation of DPSCs. The inhibition of JNK, p38, and extracellular signal-regulated kinase signaling suppressed the migration, ALP expression, and mineralization of DPSCs. Our study showed that the MAP kinase pathway was involved in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Minocycline Effects on Intracerebral Hemorrhage-Induced Iron Overload in Aged Rats: Brain Iron Quantification With Magnetic Resonance Imaging.

PubMed

Cao, Shenglong; Hua, Ya; Keep, Richard F; Chaudhary, Neeraj; Xi, Guohua

2018-04-01

Brain iron overload is a key factor causing brain injury after intracerebral hemorrhage (ICH). This study quantified brain iron levels after ICH with magnetic resonance imaging R2* mapping. The effect of minocycline on iron overload and ICH-induced brain injury in aged rats was also determined. Aged (18 months old) male Fischer 344 rats had an intracerebral injection of autologous blood or saline, and brain iron levels were measured by magnetic resonance imaging R2* mapping. Some ICH rats were treated with minocycline or vehicle. The rats were euthanized at days 7 and 28 after ICH, and brains were used for immunohistochemistry and Western blot analyses. Magnetic resonance imaging (T2-weighted, T2* gradient-echo, and R2* mapping) sequences were performed at different time points. ICH-induced brain iron overload in the perihematomal area could be quantified by R2* mapping. Minocycline treatment reduced brain iron accumulation, T2* lesion volume, iron-handling protein upregulation, neuronal cell death, and neurological deficits ( P <0.05). Magnetic resonance imaging R2* mapping is a reliable and noninvasive method, which can quantitatively measure brain iron levels after ICH. Minocycline reduced ICH-related perihematomal iron accumulation and brain injury in aged rats. © 2018 American Heart Association, Inc.

Effects of Butyltins (BTs) on Mitogen-Activated-Protein Kinase Kinase Kinase (MAP3K) and Ras Activity in Human Natural Killer Cells

PubMed Central

Celada, Lindsay J.; Whalen, Margaret M.

2013-01-01

Butyltins (BTs) contaminate the environment and are found in human blood. BTs, tributyltin (TBT) and dibutyltin (DBT), diminish the cytotoxic function and levels of key proteins of human natural killer (NK) cells. NK cells are an initial immune defense against tumors, virally-infected cells and antibody-coated cells and thus critical to human health. The signaling pathways that regulate NK cell functions include mitogen-activated protein kinases (MAPKs). Studies have shown that exposure to BTs leads to the activation of specific MAPKs and MAPK kinases (MAP2Ks) in human NK cells. MAP2K kinases (MAP3Ks) are upstream activators of MAP2Ks, which then activate MAPKs. The current study examined if BT-induced activation of MAP3Ks was responsible for MAP2K and thus, MAPK activation. This study examines the effects of TBT and DBT on the total levels of two MAP3Ks, c-Raf and ASK1, as well as activating and inhibitory phosphorylation sites on these MAP3Ks. In addition, the immediate upstream activator of c-Raf, Ras, was examined for BT-induced alterations. Our results show significant activation of the MAP3K, c-Raf, in human NK cells within 10 minutes of TBT exposure and the MAP3K, ASK1, after one hour exposures to TBT. In addition, our results suggest that both TBT and DBT are impacting the regulation of c-Raf. PMID:24038145

miR-188 promotes senescence of lineage-negative bone marrow cells by targeting MAP3K3 expression.

PubMed

Zheng, Yue; Liu, Hua; Kong, Ye

2017-08-01

Lineage-negative bone marrow cells (lin-BMCs) have reparative potential for overcoming endothelial dysfunction and reducing cardiovascular risk. Here, we found that miR-188 is upregulated and mitogen-activated protein kinase kinase kinase 3 (MAP3K3) is downregulated in aged lin-BMCs, whereas their expression is reversed in young lin-BMCs. We identified and confirmed MAP3K3 as a direct target of miR-188. MiR-188 overexpression or MAP3K3 silencing in young lin-BMCs increases p16 and p21 expression, enhances cell senescence, and decreases the ability for cell proliferation, migration, and tube formation. Conversely, miR-188 suppression in aged lin-BMCs yields the opposite results. We further found that MAP3K3 is involved in miR-188-induced promotion of lin-BMC senescence. All data reveal that miR-188 induces lin-BMC senescence by targeting MAP3K3 expression, thus, providing new theoretical basis for the prevention and treatment of cardiovascular diseases. © 2017 Federation of European Biochemical Societies.

Structure-based design, synthesis, and biological evaluation of imidazo[1,2-b]pyridazine-based p38 MAP kinase inhibitors.

PubMed

Kaieda, Akira; Takahashi, Masashi; Takai, Takafumi; Goto, Masayuki; Miyazaki, Takahiro; Hori, Yuri; Unno, Satoko; Kawamoto, Tomohiro; Tanaka, Toshimasa; Itono, Sachiko; Takagi, Terufumi; Hamada, Teruki; Shirasaki, Mikio; Okada, Kengo; Snell, Gyorgy; Bragstad, Ken; Sang, Bi-Ching; Uchikawa, Osamu; Miwatashi, Seiji

2018-02-01

We identified novel potent inhibitors of p38 MAP kinase using structure-based design strategy. X-ray crystallography showed that when p38 MAP kinase is complexed with TAK-715 (1) in a co-crystal structure, Phe169 adopts two conformations, where one interacts with 1 and the other shows no interaction with 1. Our structure-based design strategy shows that these two conformations converge into one via enhanced protein-ligand hydrophobic interactions. According to the strategy, we focused on scaffold transformation to identify imidazo[1,2-b]pyridazine derivatives as potent inhibitors of p38 MAP kinase. Among the herein described and evaluated compounds, N-oxide 16 exhibited potent inhibition of p38 MAP kinase and LPS-induced TNF-α production in human monocytic THP-1 cells, and significant in vivo efficacy in rat collagen-induced arthritis models. In this article, we report the discovery of potent, selective and orally bioavailable imidazo[1,2-b]pyridazine-based p38 MAP kinase inhibitors with pyridine N-oxide group. Copyright © 2018 Elsevier Ltd. All rights reserved.

Exact and approximate graph matching using random walks.

PubMed

Gori, Marco; Maggini, Marco; Sarti, Lorenzo

2005-07-01

In this paper, we propose a general framework for graph matching which is suitable for different problems of pattern recognition. The pattern representation we assume is at the same time highly structured, like for classic syntactic and structural approaches, and of subsymbolic nature with real-valued features, like for connectionist and statistic approaches. We show that random walk based models, inspired by Google's PageRank, give rise to a spectral theory that nicely enhances the graph topological features at node level. As a straightforward consequence, we derive a polynomial algorithm for the classic graph isomorphism problem, under the restriction of dealing with Markovian spectrally distinguishable graphs (MSD), a class of graphs that does not seem to be easily reducible to others proposed in the literature. The experimental results that we found on different test-beds of the TC-15 graph database show that the defined MSD class "almost always" covers the database, and that the proposed algorithm is significantly more efficient than top scoring VF algorithm on the same data. Most interestingly, the proposed approach is very well-suited for dealing with partial and approximate graph matching problems, derived for instance from image retrieval tasks. We consider the objects of the COIL-100 visual collection and provide a graph-based representation, whose node's labels contain appropriate visual features. We show that the adoption of classic bipartite graph matching algorithms offers a straightforward generalization of the algorithm given for graph isomorphism and, finally, we report very promising experimental results on the COIL-100 visual collection.

On P2 ⋄ Pn -supermagic labeling of edge corona product of cycle and path graph

NASA Astrophysics Data System (ADS)

Yulianto, R.; Martini, Titin S.

2018-04-01

A simple graph G = (V, E) admits a H-covering, where H is subgraph of G, if every edge in E belongs to a subgraph of G isomorphic to H. Graph G is H-magic if there is a total labeling f:V(G)\\cup E(G)\\to 1,2,\\ldots,|V(G)|+|E(G)|, such that each subgraph {H}{\\prime }=({V}{\\prime },{E}{\\prime }) of G isomorphic to H and satisfying f{({H}{\\prime })}=def{\\sum }\\upsilon \\in {V{\\prime }}f(\\upsilon )+{\\sum }e\\in {E{\\prime }}f(e)=m(f) where m(f) is a constant magic sum. Additionaly, G admits H-supermagic if f(V)=1,2,\\ldots,|V|. The edge corona {C}n \\diamond {P}n of Cn and Pn is defined as the graph obtained by taking one copy of Cn and n copies of Pn , and then joining two end-vertices of the i-th edge of Cn to every vertex in the i-th copy of Pn . This research aim is to find H-supermagic covering on an edge corona product of cycle and path graph {C}n \\diamond {P}n where H is {P}2 \\diamond {P}n. We use k-balanced multiset to solve our reserarch. Here, we find that an edge corona product of cycle and path graph {C}n \\diamond {P}n is {P}2 \\diamond {P}n supermagic for n > 3.

Neural dynamics of image representation in the primary visual cortex

PubMed Central

Yan, Xiaogang; Khambhati, Ankit; Liu, Lei; Lee, Tai Sing

2013-01-01

Horizontal connections in the primary visual cortex have been hypothesized to play a number of computational roles: association field for contour completion, surface interpolation, surround suppression, and saliency computation. Here, we argue that horizontal connections might also serve a critical role of computing the appropriate codes for image representation. That the early visual cortex or V1 explicitly represents the image we perceive has been a common assumption on computational theories of efficient coding (Olshausen and Field 1996), yet such a framework for understanding the circuitry in V1 has not been seriously entertained in the neurophysiological community. In fact, a number of recent fMRI and neurophysiological studies cast doubt on the neural validity of such an isomorphic representation (Cornelissen et al. 2006, von der Heydt et al. 2003). In this study, we investigated, neurophysiologically, how V1 neurons respond to uniform color surfaces and show that spiking activities of neurons can be decomposed into three components: a bottom-up feedforward input, an articulation of color tuning and a contextual modulation signal that is inversely proportional to the distance away from the bounding contrast border. We demonstrate through computational simulations that the behaviors of a model for image representation are consistent with many aspects of our neural observations. We conclude that the hypothesis of isomorphic representation of images in V1 remains viable and this hypothesis suggests an additional new interpretation of the functional roles of horizontal connections in the primary visual cortex. PMID:22944076

Enhanced room temperature multiferroic characteristics in hexagonal LuFe1-xNixO3 (x = 0 - 0.3) nanoparticles

NASA Astrophysics Data System (ADS)

Suresh, Pittala; Vijaya Laxmi, K.; Anil Kumar, P. S.

2018-02-01

Single phase polycrystalline LuFe1-xNixO3 (x = 0 - 0.3) (LFNO) nanoparticles are synthesized using the sol-gel method. X-ray diffraction measurements revealed that the crystal structure of Ni-doped samples is isomorphic to hexagonal LuFeO3 (LFO). The phase pure hexagonal P63cm symmetry exists for 0 ≤ x ≤ 0.3, and the secondary phases appear for x ≥ 0.4. Raman spectra show a shift in the mode frequency corresponding to the changes in Lu-O and Fe-O bond lengths with Ni doping. An enhancement in the magnetization is observed for LFNO throughout the temperature range (400-5 K) compared to LFO. The antiferromagnetic state of LFO becomes ferrimagnetic at low temperatures, and a net magnetization is observed at room temperature with Ni doping. As Ni concentration increases, a systematic increment in the ferroelectric polarization is observed. This enhancement in polarization is believed to be due to the distortion in FeO5 cage, while the improvement in magnetic properties is due to the induced magnetic interactions, caused by the Fe-Ni interactions on the triangular lattice with Ni doping in LuFeO3.

Transportable Manned and Robotic Digital Geophysical Mapping Tow Vehicle, Phase 1

DTIC Science & Technology

2007-08-01

by using the UX PROCESS QC/QA tools to evaluate quality. Areas evaluated included induced noise, position and track accuracy, synchronization/latency... tools . To gain additional data on productivity and the effect of alternate direction of travel we mapped an unobstructed subset of the Grid 1-4 area...independently evaluated by using the UX PROCESS QC/QA tools to evaluate quality. Areas evaluated included induced noise, position and track

Acrylamide inhibits cellular differentiation of human neuroblastoma and glioblastoma cells.

PubMed

Chen, Jong-Hang; Chou, Chin-Cheng

2015-08-01

This study explores human neuroblastoma (SH-SY5Y) and human glioblastoma (U-1240 MG) cellular differentiation changes under exposure to acrylamide (ACR). Differentiation of SH-SY5Y and U-1240 MG cells were induced by retinoic acid (RA) and butyric acid (BA), respectively. Morphological observations and MTT assay showed that the induced cellular differentiation and cell proliferation were inhibited by ACR in a time- and dose-dependent manner. ACR co-treatment with RA attenuated SH-SY5Y expressions of neurofilament protein-L (NF-L), microtubule-associated protein 1b (MAP1b; 1.2 to 0.7, p < 0.001), MAP2c (2.2 to 0.8, p < 0.05), and Janus kinase1 (JAK1; 1.9 to 0.6, p < 0.001), while ACR co-treatment with BA attenuated U-1240 MG expressions of glial fibrillary acidic protein (GFAP), MAP1b (1.2 to 0.6, p < 0.001), MAP2c (1.5 to 0.7, p < 0.01), and JAK1 (2.1 to 0.5, p < 0.001), respectively. ACR also decreased the phosphorylation of extracellular-signal-regulated kinases (ERK) and c-Jun N-terminal kinases (JNK) in U-1240 MG cells, while caffeine reversed this suppression of ERK and JNK phosphorylation caused by ACR treatment. These results showed that RA-induced neurogenesis of SH-SY5Y and BA-induced astrogliogenesis of U-1240 MG cells were attenuated by ACR and were associated with down-regulation of MAPs expression and JAK-STAT signaling. Copyright © 2015 Elsevier Ltd. All rights reserved.

Investigation of Thermal Effects of Photocoagulation on Retinal Tissue Using Fine-Motion-Sensitive Dynamic Optical Coherence Tomography.

PubMed

Kurokawa, Kazuhiro; Makita, Shuichi; Yasuno, Yoshiaki

2016-01-01

To enable an objective evaluation of photocoagulation, we characterize thermal tissue changes induced by laser irradiation with different laser parameters using optical coherence tomography (OCT). Spectral-domain OCT with a newly developed image processing method was used to monitor the thermal changes of ex vivo porcine retina. A sequence of OCT B-scans was obtained at the same retinal position simultaneously with the photocoagulation. Cross-sectional tissue displacement maps with respect to an OCT image taken before laser irradiation were computed for images taken before, during, and after laser irradiation, by using a correlation-based custom algorithm. Cross-sectional correlation maps (OCT correlation maps) were also computed from an OCT image taken before laser irradiation as a base-line to visualize alterations of tissue microstructure induced by laser irradiation. By systematically controlling laser power and exposure times, tissue displacements and structural changes of 200 retinal regions of 10 porcine eyes were characterized. Thermal tissue changes were characterized by B-scan images, OCT correlation maps, and tissue displacement maps. Larger tissue deformation was induced with higher laser power and shorter exposure time, while the same total laser energy (10 mJ) was applied. The measured tissue displacements revealed the complicated dynamics of tissue displacements. Three types of dynamics were observed; lateral expansion, lateral constriction, and a type showing more complicated dynamics. The results demonstrated the ability of this OCT-based method to evaluate retinal changes induced by laser irradiation. This evaluation could lead to further understanding of thermal effects, and increasing reproducibility of photocoagulation therapy.

A forskolin derivative, colforsin daropate hydrochloride, inhibits the decrease in cortical renal blood flow induced by noradrenaline or angiotensin II in anesthetized rats.

PubMed

Ogata, Junichi; Minami, Kouichiro; Segawa, Kayoko; Uezono, Yasuhito; Shiraishi, Munehiro; Yamamoto, Chikako; Sata, Takeyoshi; Sung-Teh, Kim; Shigematsu, Akio

2004-01-01

A forskolin derivative, colforsin daropate hydrochloride (CDH), acts directly on adenylate cyclase to increase the intracellular cyclic adenosine monophosphate levels which produce a positive inotropic effect and a lower blood pressure. However, little is known about the effects of CDH on the renal function. We used laser Doppler flowmetry to measure the cortical renal blood flow (RBF) in male Wistar rats given a continuous intravenous infusion of CDH and evaluated the effects of CDH on the noradrenaline (NA) and angiotensin II (AngII) induced increases in blood pressure and reductions in RBF. Continuous intravenous administration of CDH at 0.25 microg/kg/min did not affect the mean arterial pressure (MAP), but increased heart rate and RBF. Continuous intravenous administration of CDH at high doses (0.5-0.75 microg/kg/min) decreased the MAP, with little effect on the RBF. The administration of exogenous NA (1.7 microg/kg) increased the MAP and decreased the RBF. However, a bolus injection of NA did not decrease the RBF during continuous intravenous administration of CDH, and CDH did not affect the NA-induced increase in MAP. The administration of exogenous AngII (100 ng/kg) increased MAP and decreased RBF and heart rate, but a bolus injection of AngII did not decrease RBF during continuous intravenous administration of CDH. These results suggest that CDH plays a protective role against the pressor effects and the decrease in RBF induced by NA or AngII. Copyright 2004 S. Karger AG, Basel

The Role of Endogenous Neurogenesis in Functional Recovery and Motor Map Reorganization Induced by Rehabilitative Therapy after Stroke in Rats.

PubMed

Shiromoto, Takashi; Okabe, Naohiko; Lu, Feng; Maruyama-Nakamura, Emi; Himi, Naoyuki; Narita, Kazuhiko; Yagita, Yoshiki; Kimura, Kazumi; Miyamoto, Osamu

2017-02-01

Endogenous neurogenesis is associated with functional recovery after stroke, but the roles it plays in such recovery processes are unknown. This study aims to clarify the roles of endogenous neurogenesis in functional recovery and motor map reorganization induced by rehabilitative therapy after stroke by using a rat model of cerebral ischemia (CI). Ischemia was induced via photothrombosis in the caudal forelimb area of the rat cortex. First, we examined the effect of rehabilitative therapy on functional recovery and motor map reorganization, using the skilled forelimb reaching test and intracortical microstimulation. Next, using the same approaches, we examined how motor map reorganization changed when endogenous neurogenesis after stroke was inhibited by cytosine-β-d-arabinofuranoside (Ara-C). Rehabilitative therapy for 4 weeks after the induction of stroke significantly improved functional recovery and expanded the rostral forelimb area (RFA). Intraventricular Ara-C administration for 4-10 days after stroke significantly suppressed endogenous neurogenesis compared to vehicle, but did not appear to influence non-neural cells (e.g., microglia, astrocytes, and vascular endothelial cells). Suppressing endogenous neurogenesis via Ara-C administration significantly inhibited (~50% less than vehicle) functional recovery and RFA expansion (~33% of vehicle) induced by rehabilitative therapy after CI. After CI, inhibition of endogenous neurogenesis suppressed both the functional and anatomical markers of rehabilitative therapy. These results suggest that endogenous neurogenesis contributes to functional recovery after CI related to rehabilitative therapy, possibly through its promotion of motor map reorganization, although other additional roles cannot be ruled out. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

The Ste20 Family Kinases MAP4K4, MINK1, and TNIK Converge to Regulate Stress-Induced JNK Signaling in Neurons.

PubMed

Larhammar, Martin; Huntwork-Rodriguez, Sarah; Rudhard, York; Sengupta-Ghosh, Arundhati; Lewcock, Joseph W

2017-11-15

The c-Jun- N -terminal kinase (JNK) signaling pathway regulates nervous system development, axon regeneration, and neuronal degeneration after acute injury or in chronic neurodegenerative disease. Dual leucine zipper kinase (DLK) is required for stress-induced JNK signaling in neurons, yet the factors that initiate DLK/JNK pathway activity remain poorly defined. In the present study, we identify the Ste20 kinases MAP4K4, misshapen-like kinase 1 (MINK1 or MAP4K6) and TNIK Traf2- and Nck-interacting kinase (TNIK or MAP4K7), as upstream regulators of DLK/JNK signaling in neurons. Using a trophic factor withdrawal-based model of neurodegeneration in both male and female embryonic mouse dorsal root ganglion neurons, we show that MAP4K4, MINK1, and TNIK act redundantly to regulate DLK activation and downstream JNK-dependent phosphorylation of c-Jun in response to stress. Targeting MAP4K4, MINK1, and TNIK, but not any of these kinases individually, is sufficient to protect neurons potently from degeneration. Pharmacological inhibition of MAP4Ks blocks stabilization and phosphorylation of DLK within axons and subsequent retrograde translocation of the JNK signaling complex to the nucleus. These results position MAP4Ks as important regulators of the DLK/JNK signaling pathway. SIGNIFICANCE STATEMENT Neuronal degeneration occurs in disparate circumstances: during development to refine neuronal connections, after injury to clear damaged neurons, or pathologically during disease. The dual leucine zipper kinase (DLK)/c-Jun- N -terminal kinase (JNK) pathway represents a conserved regulator of neuronal injury signaling that drives both neurodegeneration and axon regeneration, yet little is known about the factors that initiate DLK activity. Here, we uncover a novel role for a subfamily of MAP4 kinases consisting of MAP4K4, Traf2- and Nck-interacting kinase (TNIK or MAP4K7), and misshapen-like kinase 1 (MINK1 or MAP4K6) in regulating DLK/JNK signaling in neurons. Inhibition of these MAP4Ks blocks stress-induced retrograde JNK signaling and protects from neurodegeneration, suggesting that these kinases may represent attractive therapeutic targets. Copyright © 2017 the authors 0270-6474/17/3711074-11$15.00/0.

Planck intermediate results: XLI. A map of lensing-induced B-modes

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

Ade, P. A. R.; Aghanim, N.; Ashdown, M.

The secondary cosmic microwave background (CMB) B-modes stem from the post-decoupling distortion of the polarization E-modes due to the gravitational lensing effect of large-scale structures. These lensing-induced B-modes constitute both a valuable probe of the dark matter distribution and an important contaminant for the extraction of the primary CMB B-modes from inflation. Planck provides accurate nearly all-sky measurements of both the polarization E-modes and the integrated mass distribution via the reconstruction of the CMB lensing potential. By combining these two data products, we have produced in this paper an all-sky template map of the lensing-induced B-modes using a real-space algorithmmore » that minimizes the impact of sky masks. The cross-correlation of this template with an observed (primordial and secondary) B-mode map can be used to measure the lensing B-mode power spectrum at multipoles up to 2000. In particular, when cross-correlating with the B-mode contribution directly derived from the Planck polarization maps, we obtain lensing-induced B-mode power spectrum measurement at a significance level of 12σ, which agrees with the theoretical expectation derived from the Planck best-fit Λ cold dark matter model. This unique nearly all-sky secondary B-mode template, which includes the lensing-induced information from intermediate to small (10 ≲ ℓ ≲ 1000) angular scales, is delivered as part of the Planck 2015 public data release. Finally, it will be particularly useful for experiments searching for primordial B-modes, such as BICEP2/Keck Array or LiteBIRD, since it will enable an estimate to be made of the lensing-induced contribution to the measured total CMB B-modes.« less

Planck intermediate results. XLI. A map of lensing-induced B-modes

NASA Astrophysics Data System (ADS)

Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartolo, N.; Basak, S.; Battaner, E.; Benabed, K.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Chiang, H. C.; Christensen, P. R.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davis, R. J.; de Bernardis, P.; de Zotti, G.; Delabrouille, J.; Dickinson, C.; Diego, J. M.; Doré, O.; Ducout, A.; Dupac, X.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Galeotta, S.; Galli, S.; Ganga, K.; Ghosh, T.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gruppuso, A.; Gudmundsson, J. E.; Harrison, D. L.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hornstrup, A.; Hovest, W.; Hurier, G.; Jaffe, A. H.; Jones, W. C.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Knoche, J.; Knox, L.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Leonardi, R.; Levrier, F.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maffei, B.; Maggio, G.; Maino, D.; Mandolesi, N.; Mangilli, A.; Maris, M.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; Meinhold, P. R.; Melchiorri, A.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Novikov, D.; Novikov, I.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Pettorino, V.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pointecouteau, E.; Polenta, G.; Pratt, G. W.; Rachen, J. P.; Reinecke, M.; Remazeilles, M.; Renault, C.; Renzi, A.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rossetti, M.; Roudier, G.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Scott, D.; Spencer, L. D.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Wehus, I. K.; Yvon, D.; Zacchei, A.; Zonca, A.

2016-12-01

The secondary cosmic microwave background (CMB) B-modes stem from the post-decoupling distortion of the polarization E-modes due to the gravitational lensing effect of large-scale structures. These lensing-induced B-modes constitute both a valuable probe of the dark matter distribution and an important contaminant for the extraction of the primary CMB B-modes from inflation. Planck provides accurate nearly all-sky measurements of both the polarization E-modes and the integrated mass distribution via the reconstruction of the CMB lensing potential. By combining these two data products, we have produced an all-sky template map of the lensing-induced B-modes using a real-space algorithm that minimizes the impact of sky masks. The cross-correlation of this template with an observed (primordial and secondary) B-mode map can be used to measure the lensing B-mode power spectrum at multipoles up to 2000. In particular, when cross-correlating with the B-mode contribution directly derived from the Planck polarization maps, we obtain lensing-induced B-mode power spectrum measurement at a significance level of 12σ, which agrees with the theoretical expectation derived from the Planck best-fit Λ cold dark matter model. This unique nearly all-sky secondary B-mode template, which includes the lensing-induced information from intermediate to small (10 ≲ ℓ ≲ 1000) angular scales, is delivered as part of the Planck 2015 public data release. It will be particularly useful for experiments searching for primordial B-modes, such as BICEP2/Keck Array or LiteBIRD, since it will enable an estimate to be made of the lensing-induced contribution to the measured total CMB B-modes.

Planck intermediate results: XLI. A map of lensing-induced B-modes

DOE PAGES

Ade, P. A. R.; Aghanim, N.; Ashdown, M.; ...

2016-12-12

The secondary cosmic microwave background (CMB) B-modes stem from the post-decoupling distortion of the polarization E-modes due to the gravitational lensing effect of large-scale structures. These lensing-induced B-modes constitute both a valuable probe of the dark matter distribution and an important contaminant for the extraction of the primary CMB B-modes from inflation. Planck provides accurate nearly all-sky measurements of both the polarization E-modes and the integrated mass distribution via the reconstruction of the CMB lensing potential. By combining these two data products, we have produced in this paper an all-sky template map of the lensing-induced B-modes using a real-space algorithmmore » that minimizes the impact of sky masks. The cross-correlation of this template with an observed (primordial and secondary) B-mode map can be used to measure the lensing B-mode power spectrum at multipoles up to 2000. In particular, when cross-correlating with the B-mode contribution directly derived from the Planck polarization maps, we obtain lensing-induced B-mode power spectrum measurement at a significance level of 12σ, which agrees with the theoretical expectation derived from the Planck best-fit Λ cold dark matter model. This unique nearly all-sky secondary B-mode template, which includes the lensing-induced information from intermediate to small (10 ≲ ℓ ≲ 1000) angular scales, is delivered as part of the Planck 2015 public data release. Finally, it will be particularly useful for experiments searching for primordial B-modes, such as BICEP2/Keck Array or LiteBIRD, since it will enable an estimate to be made of the lensing-induced contribution to the measured total CMB B-modes.« less

Calpeptin is neuroprotective against acrylamide-induced neuropathy in rats.

PubMed

Su, Benyu; Guan, Qiangdong; Wang, Miaomiao; Liu, Ning; Wei, Xiaomin; Wang, Shue; Yang, Xiwei; Jiang, Wenchong; Xu, Mengmeng; Yu, Sufang

2018-05-01

The aim of this study is to explore the potent neuroprotective effect of calpeptin (CP) on neuron damage induced by acrylamide (ACR) and its mechanism. Behavioural indicators such as hind limb splay, rota-rod performance, and gait analysis were assessed weekly to evaluate neurobehavioural changes after ACR and/or CP administration. The histopathological alterations and the changes of μ-calpain, m-calpain, microtubule-associated protein 2 (MAP2), and α-tubulin and β-tubulin protein levels in spinal cord were determined. Results showed that after administration of 30 mg/kg ACR, decreased body weight, attenuated neurobehavioural function, injury of motor neuron, increased protein levels of m-calpain and β-tubulin, suppressed MAP2 protein level, and no significant changes of μ-calpain and α-tubulin protein levels were observed compared with the control group rats. After administration of 200 μg/kg CP, partially restored body weight and neurobehavioural function, improvement of motor neuron injury, decreased protein levels of m- calpain and β-tubulin, and reversed effects of MAP2 protein level were observed compared with the ACR group rats. Our results suggested that CP alleviates neuropathy induced by ACR in rats. The calpain's overactivation causes the degrading of MAP2 and eventually leads to the destruction of microtubules (MTs), which may be one of the mechanisms of cytoskeletal damage induced by ACR. Copyright © 2018 Elsevier B.V. All rights reserved.

Utilization of selected laser-ablation-based diagnostic methods for study of elemental distribution in various solid samples

NASA Astrophysics Data System (ADS)

Kaiser, J.; Novotný, K.; Hrdlička, A.; Malina, R.; Novotný, J.; Prochazka, D.; Petrilak, M.; Krajcarová, L.; Vítková, G.; Kučerová, P.

2010-12-01

Here we report on the recent developments and upgrades of our Laser-Induced Breakdown Spectroscopy setups and their different modification for high-resolution mapping. Mapping capabilities of Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry are compared. The applied improvements as an autofocus algorithm, together with the realization of double-pulse LIBS or combination of LIBS by Laser-Induced Fluorescence Spectroscopy (LIFS) with technique are detailed. The signal enhancement obtained by double-pulse approach is demonstrated. The state of the art on development of portable remote LIBS apparatus is also presented.

Effects of gravity reduction on phase equilibria. Part 1: Unary and binary isostructural solids

NASA Technical Reports Server (NTRS)

Larson, D. J., Jr.

1975-01-01

Analysis of the Skylab II M553 Experiment samples resulted in the hypothesis that the reduced gravity environment was altering the melting and solidification reactions. A theoretical study was conducted to define the conditions under which such alteration of phase relations is feasible, determine whether it is restricted to space processing, and, if so, ascertain which alloy systems or phase reactions are most likely to demonstrate such effects. Phase equilibria of unary and binary systems with a single solid phase (unary and isomorphous) were considered.

Status Report on Speech Research. A Report on the Status and Progress of Studies on the Nature of Speech, Instrumentation for Its Investigation, and Practical Applications.

DTIC Science & Technology

1983-09-30

determines, in part, what the infant says; and if perception is to guide production, the two processes must be, in some sense, isomorphic. An artificial speech ...influences on speech perception processes . Perception & Psychophysics, 24, 253-257. MacKain, K. S., Studdert-Kennedy, M., Spieker, S., & Stern, D. (1983...sentence contexts. In A. Cohen & S. E. G. Nooteboom (Eds.), Structure and process in speech perception (pp. 69-89). New York: Springer- Verlag. Larkey

Spin generalization of the Calogero–Moser hierarchy and the matrix KP hierarchy

NASA Astrophysics Data System (ADS)

Pashkov, V.; Zabrodin, A.

2018-05-01

We establish a correspondence between rational solutions to the matrix KP hierarchy and the spin generalization of the Calogero–Moser system on the level of hierarchies. Namely, it is shown that the rational solutions to the matrix KP hierarchy appear to be isomorphic to the spin Calogero–Moser system in a sense that the dynamics of poles of solutions to the matrix KP hierarchy in the higher times is governed by the higher Hamiltonians of the spin Calogero–Moser integrable hierarchy with rational potential.

Isomonodromy for the Degenerate Fifth Painlevé Equation

NASA Astrophysics Data System (ADS)

Acosta-Humánez, Primitivo B.; van der Put, Marius; Top, Jaap

2017-05-01

This is a sequel to papers by the last two authors making the Riemann-Hilbert correspondence and isomonodromy explicit. For the degenerate fifth Painlevé equation, the moduli spaces for connections and for monodromy are explicitly computed. It is proven that the extended Riemann-Hilbert morphism is an isomorphism. As a consequence these equations have the Painlevé property and the Okamoto-Painlevé space is identified with a moduli space of connections. Using MAPLE computations, one obtains formulas for the degenerate fifth Painlevé equation, for the Bäcklund transformations.

Communication: Two measures of isochronal superposition

NASA Astrophysics Data System (ADS)

Roed, Lisa Anita; Gundermann, Ditte; Dyre, Jeppe C.; Niss, Kristine

2013-09-01

A liquid obeys isochronal superposition if its dynamics is invariant along the isochrones in the thermodynamic phase diagram (the curves of constant relaxation time). This paper introduces two quantitative measures of isochronal superposition. The measures are used to test the following six liquids for isochronal superposition: 1,2,6 hexanetriol, glycerol, polyphenyl ether, diethyl phthalate, tetramethyl tetraphenyl trisiloxane, and dibutyl phthalate. The latter four van der Waals liquids obey isochronal superposition to a higher degree than the two hydrogen-bonded liquids. This is a prediction of the isomorph theory, and it confirms findings by other groups.

Communication: Two measures of isochronal superposition.

PubMed

Roed, Lisa Anita; Gundermann, Ditte; Dyre, Jeppe C; Niss, Kristine

2013-09-14

A liquid obeys isochronal superposition if its dynamics is invariant along the isochrones in the thermodynamic phase diagram (the curves of constant relaxation time). This paper introduces two quantitative measures of isochronal superposition. The measures are used to test the following six liquids for isochronal superposition: 1,2,6 hexanetriol, glycerol, polyphenyl ether, diethyl phthalate, tetramethyl tetraphenyl trisiloxane, and dibutyl phthalate. The latter four van der Waals liquids obey isochronal superposition to a higher degree than the two hydrogen-bonded liquids. This is a prediction of the isomorph theory, and it confirms findings by other groups.

New oxyfluorotellurates(IV): MTeO3F (M = FeIII, GaIII and CrIII).

PubMed

Laval, Jean Paul; Jennene Boukharrata, Nefla; Thomas, Philippe

2008-02-01

The crystal structures of the new isomorphous compounds iron(III) oxyfluorotellurate(IV), FeTeO(3)F, gallium(III) oxyfluorotellurate(IV), GaTeO(3)F, and chromium(III) oxyfluorotellurate(IV), CrTeO(3)F, consist of zigzag chains of MO(4)F(2) distorted octahedra alternately sharing O-O and F-F edges and connected via TeO(3) trigonal pyramids. A full O/F anionic ordering is observed and the electronic lone pair of the Te(IV) cation is stereochemically active.

Isomorphism Within the Hexagonal Columnar Mesophase of Molecular and Macromolecular Self- and Co-Assembled Columns Containing Tapered Groups

DTIC Science & Technology

1994-06-30

benzyloxylbenzoic acid , their corresponding polymethacrylates , and of 4’- methyl (benzo- 15-crown-5)-3,4,5-tris[4-(n-dodecan- 1 -yloxy)benzyloxylbenzoate within...l-yloxy)benzyloxy]benzoic acid , of their corresponding polymethacrylates , and of 4’-methyl(benzo- 15-crown-5)-3,4,5-tris[4- (n-dodecan- 1-yloxy...benzyloxylbenzoic acid , of their corresponding polymethacrylates ,18a and of 4’-methyl(benzo-15-crown-5)-3,4,5-tris[4-(n-dodecan-l- yloxy)benzyloxy]benzoate 1 7

Functional microporous materials of metal carboxylate: Gas-occlusion properties and catalytic activities

NASA Astrophysics Data System (ADS)

Mori, Wasuke; Sato, Tomohiko; Ohmura, Tesushi; Nozaki Kato, Chika; Takei, Tohru

2005-08-01

Copper(II) terephthalate is the first transition metal complex found capable of adsorbing gases. This complex has opened the new field of adsorbent complex chemistry. It is recognized as the lead complex in the construction of microporous complexes. This specific system has been expanded to a systematic series of derivatives of other isomorphous transition metals, molybdenum(II), ruthenium(II, III), and rhodium(II). These complexes with open frameworks are widely recognized as very useful materials for applications to catalysis, separation at molecular level, and gas storage.

Protein Kinase G Induces an Immune Response in Cows Exposed to Mycobacterium avium Subsp. paratuberculosis

PubMed Central

Bach, Eviatar; Chaffer, Marcelo; Lai, Wanika; Keefe, Greg; Begg, Douglas J.

2018-01-01

To establish infection, pathogens secrete virulence factors, such as protein kinases and phosphatases, to modulate the signal transduction pathways used by host cells to initiate immune response. The protein MAP3893c is annotated in the genome sequence of Mycobacterium avium subspecies paratuberculosis (MAP), the causative agent of Johne's disease, as the serine/threonine protein kinase G (PknG). In this work, we report that PknG is a functional kinase that is secreted within macrophages at early stages of infection. The antigen is able to induce an immune response from cattle exposed to MAP in the form of interferon gamma production after stimulation of whole blood with PknG. These findings suggest that PknG may contribute to the pathogenesis of MAP by phosphorylating macrophage signalling and/or adaptor molecules as observed with other pathogenic mycobacterial species. PMID:29581962

Protein Kinase G Induces an Immune Response in Cows Exposed to Mycobacterium avium Subsp. paratuberculosis.

PubMed

Bach, Horacio; Richard-Greenblatt, Melissa; Bach, Eviatar; Chaffer, Marcelo; Lai, Wanika; Keefe, Greg; Begg, Douglas J

2018-01-01

To establish infection, pathogens secrete virulence factors, such as protein kinases and phosphatases, to modulate the signal transduction pathways used by host cells to initiate immune response. The protein MAP3893c is annotated in the genome sequence of Mycobacterium avium subspecies paratuberculosis (MAP), the causative agent of Johne's disease, as the serine/threonine protein kinase G (PknG). In this work, we report that PknG is a functional kinase that is secreted within macrophages at early stages of infection. The antigen is able to induce an immune response from cattle exposed to MAP in the form of interferon gamma production after stimulation of whole blood with PknG. These findings suggest that PknG may contribute to the pathogenesis of MAP by phosphorylating macrophage signalling and/or adaptor molecules as observed with other pathogenic mycobacterial species.

Parallel regulation of feedforward inhibition and excitation during whisker map plasticity

PubMed Central

House, David RC; Elstrott, Justin; Koh, Eileen; Chung, Jason; Feldman, Daniel E.

2011-01-01

Sensory experience drives robust plasticity of sensory maps in cerebral cortex, but the role of inhibitory circuits in this process is not fully understood. We show that classical deprivation-induced whisker map plasticity in layer 2/3 (L2/3) of rat somatosensory (S1) cortex involves robust weakening of L4-L2/3 feedforward inhibition. This weakening was caused by reduced L4 excitation onto L2/3 fast-spiking (FS) interneurons, which mediate sensitive feedforward inhibition, and was partially offset by strengthening of unitary FS to L2/3 pyramidal cell synapses. Weakening of feedforward inhibition paralleled the known weakening of feedforward excitation, so that mean excitatory-inhibitory balance and timing onto L2/3 pyramidal cells were preserved. Thus, reduced feedforward inhibition is a covert compensatory process that can maintain excitatory-inhibitory balance during classical deprivation-induced Hebbian map plasticity. PMID:22153377

Phenylephrine-induced elevations in arterial blood pressure are attenuated in heat-stressed humans

NASA Technical Reports Server (NTRS)

Cui, Jian; Wilson, Thad E.; Crandall, Craig G.

2002-01-01

To test the hypothesis that phenylephrine-induced elevations in blood pressure are attenuated in heat-stressed humans, blood pressure was elevated via steady-state infusion of three doses of phenylephrine HCl in 10 healthy subjects in both normothermic and heat stress conditions. Whole body heating significantly increased sublingual temperature by 0.5 degrees C, muscle sympathetic nerve activity (MSNA), heart rate, and cardiac output and decreased total peripheral vascular resistance (TPR; all P < 0.005) but did not change mean arterial blood pressure (MAP; P > 0.05). At the highest dose of phenylephrine, the increase in MAP and TPR from predrug baselines was significantly attenuated during the heat stress [DeltaMAP 8.4 +/- 1.2 mmHg; DeltaTPR 0.96 +/- 0.85 peripheral resistance units (PRU)] compared with normothermia (DeltaMAP 15.4 +/- 1.4 mmHg, DeltaTPR 7.13 +/- 1.18 PRU; all P < 0.001). The sensitivity of baroreflex control of MSNA and heart rate, expressed as the slope of the relationship between MSNA and diastolic blood pressure, as well as the slope of the relationship between heart rate and systolic blood pressure, respectively, was similar between thermal conditions (each P > 0.05). These data suggest that phenylephrine-induced elevations in MAP are attenuated in heat-stressed humans without affecting baroreflex control of MSNA or heart rate.

Effect of DA-9701 on Colorectal Distension-Induced Visceral Hypersensitivity in a Rat Model

PubMed Central

Kim, Eun Ran; Min, Byung-Hoon; Lee, Tae Ho; Son, Miwon; Rhee, Poong-Lyul

2014-01-01

Background/Aims DA-9701 is a newly developed drug made from the vegetal extracts of Pharbitidis semen and Co-rydalis tuber. The aim of this study was to evaluate the effect of DA-9701 on colorectal distension (CRD)-induced visceral hypersensitivity in a rat model. Methods Male Sprague-Dawley rats were subjected to neonatal colon irritation (CI) using CRD at 1 week after birth (CI group). At 6 weeks after birth, CRD was applied to these rats with a pressure of 20 to 90 mm Hg, and changes in the mean arterial pressure (MAP) were measured at baseline (i.e., without any drug administration) and after the administration of different doses of DA-9701. Results In the absence of DA-9701, the MAP changes after CRD were significantly higher in the CI group than in the control group at all applied pressures. In the control group, MAP changes after CRD were not significantly affected by the administration of DA-9701. In the CI group, however, the administration of DA-9701 resulted in a significant decrease in MAP changes after CRD. The administration of DA-9701 at a dose of 1.0 mg/kg produced a more significant decrease in MAP changes than the 0.3 mg/kg dose. Conclusions The administration of DA-9701 resulted in a significant increase in pain threshold in rats with CRD-induced visceral hypersensitivity. PMID:25071903

Static magnetic field blood pressure buffering, baroreflex vs. vascular blood pressure control mechanism.

PubMed

Gmitrov, Juraj

2010-02-01

We compared the effect of static magnetic field (SMF) and verapamil, a potent vascular calcium channel blocking agent, on sudden elevation in blood pressure in conjunction with arterial baroreflex sensitivity (BRS) and microcirculation. Forty-four experiments were performed on conscious rabbits sedated using pentobarbital intravenous (i.v.) infusion (5 mg kg(-1) h(-1)). Mean femoral artery blood pressure (MAP), heart rate, BRS and ear lobe skin microcirculatory blood flow, estimated using microphotoelectric plethysmography (MPPG), were simultaneously measured after a 40 min exposure of the sinocarotid baroreceptors to 350 mT SMF, generated by Nd(2)-Fe(14)-B magnets, or 30 min of verapamil i.v. administration (20 microg kg(-1) min(-1)). BRS was assessed from heart rate and MAP responses to i.v. bolus of nitroprusside and phenylephrine. The decrease in phenylephrine-induced abrupt elevation in MAP (DeltaMAP(AE)) was significantly larger after verapamil than after SMF exposure. DeltaMAP(AE) inversely correlated with verapamil-induced significant increase in DeltaMPPG (r = 0.53, p < 0.000) and with SMF-induced significant increase in DeltaBRS (r = 0.47, p < 0.016). Our results suggest that verapamil-potentiated vascular blood pressure buffering mechanism was more effective than SMF-potentiated baroreflex-mediated blood pressure buffering mechanism, and a potential benefit of both approaches in cardiovascular conditions with abrupt high elevation in blood pressure.

Osmostress induces autophosphorylation of Hog1 via a C-terminal regulatory region that is conserved in p38α.

PubMed

Maayan, Inbal; Beenstock, Jonah; Marbach, Irit; Tabachnick, Shira; Livnah, Oded; Engelberg, David

2012-01-01

Many protein kinases require phosphorylation at their activation loop for induction of catalysis. Mitogen-activated protein kinases (MAPKs) are activated by a unique mode of phosphorylation, on neighboring Tyrosine and Threonine residues. Whereas many kinases obtain their activation via autophosphorylation, MAPKs are usually phosphorylated by specific, dedicated, MAPK kinases (MAP2Ks). Here we show however, that the yeast MAPK Hog1, known to be activated by the MAP2K Pbs2, is activated in pbs2Δ cells via an autophosphorylation activity that is induced by osmotic pressure. We mapped a novel domain at the Hog1 C-terminal region that inhibits this activity. Removal of this domain provides a Hog1 protein that is partially independent of MAP2K, namely, partially rescues osmostress sensitivity of pbs2Δ cells. We further mapped a short domain (7 amino acid residues long) that is critical for induction of autophosphorylation. Its removal abolishes autophosphorylation, but maintains Pbs2-mediated phosphorylation. This 7 amino acids stretch is conserved in the human p38α. Similar to the case of Hog1, it's removal from p38α abolishes p38α's autophosphorylation capability, but maintains, although reduces, its activation by MKK6. This study joins a few recent reports to suggest that, like many protein kinases, MAPKs are also regulated via induced autoactivation.

Osmostress Induces Autophosphorylation of Hog1 via a C-Terminal Regulatory Region That Is Conserved in p38α

PubMed Central

Maayan, Inbal; Beenstock, Jonah; Marbach, Irit; Tabachnick, Shira; Livnah, Oded; Engelberg, David

2012-01-01

Many protein kinases require phosphorylation at their activation loop for induction of catalysis. Mitogen-activated protein kinases (MAPKs) are activated by a unique mode of phosphorylation, on neighboring Tyrosine and Threonine residues. Whereas many kinases obtain their activation via autophosphorylation, MAPKs are usually phosphorylated by specific, dedicated, MAPK kinases (MAP2Ks). Here we show however, that the yeast MAPK Hog1, known to be activated by the MAP2K Pbs2, is activated in pbs2Δ cells via an autophosphorylation activity that is induced by osmotic pressure. We mapped a novel domain at the Hog1 C-terminal region that inhibits this activity. Removal of this domain provides a Hog1 protein that is partially independent of MAP2K, namely, partially rescues osmostress sensitivity of pbs2Δ cells. We further mapped a short domain (7 amino acid residues long) that is critical for induction of autophosphorylation. Its removal abolishes autophosphorylation, but maintains Pbs2-mediated phosphorylation. This 7 amino acids stretch is conserved in the human p38α. Similar to the case of Hog1, it’s removal from p38α abolishes p38α’s autophosphorylation capability, but maintains, although reduces, its activation by MKK6. This study joins a few recent reports to suggest that, like many protein kinases, MAPKs are also regulated via induced autoactivation. PMID:22984552

Effect of DA-9701 on colorectal distension-induced visceral hypersensitivity in a rat model.

PubMed

Kim, Eun Ran; Min, Byung-Hoon; Lee, Tae Ho; Son, Miwon; Rhee, Poong-Lyul

2014-07-01

DA-9701 is a newly developed drug made from the vegetal extracts of Pharbitidis semen and Co-rydalis tuber. The aim of this study was to evaluate the effect of DA-9701 on colorectal distension (CRD)-induced visceral hypersensitivity in a rat model. Male Sprague-Dawley rats were subjected to neonatal colon irritation (CI) using CRD at 1 week after birth (CI group). At 6 weeks after birth, CRD was applied to these rats with a pressure of 20 to 90 mm Hg, and changes in the mean arterial pressure (MAP) were measured at baseline (i.e., without any drug administration) and after the administration of different doses of DA-9701. In the absence of DA-9701, the MAP changes after CRD were significantly higher in the CI group than in the control group at all applied pressures. In the control group, MAP changes after CRD were not significantly affected by the administration of DA-9701. In the CI group, however, the administration of DA-9701 resulted in a significant decrease in MAP changes after CRD. The administration of DA-9701 at a dose of 1.0 mg/kg produced a more significant decrease in MAP changes than the 0.3 mg/kg dose. The administration of DA-9701 resulted in a significant increase in pain threshold in rats with CRD-induced visceral hypersensitivity.

Novel evidence that nitric oxide of the medial septal area influences the salivary secretion induced by pilocarpine.

PubMed

Saad, Wilson Abrão; Guarda, Ismael Francisco Motta Siqueira; Camargo, Luiz Antonio de Arruda; dos Santos, Talmir Augusto Faria Brisola; Saad, William Abrão; Simões, Sylvio; Guarda, Renata Saad

2002-04-05

Our studies have focused on the effect of injection of L-NAME and sodium nitroprussiate (SNP) on the salivary secretion, arterial blood pressure, sodium excretion and urinary volume induced by pilocarpine which was injected into the medial septal area (MSA). Rats were anesthetized with urethane (1.25 g/kg b. wt.) and a stainless steel cannula was implanted into their MSA. The amount of saliva secretion was studied over a five-minute period after injection of pilocarpine into MSA. Injection of pilocarpine (10, 20, 40, 80, 160 microg/microl) into MSA produced a dose-dependent increase in salivary secretion. L-NG-nitro arginine methyl-esther (L-NAME) (40 microg/microl), a nitric oxide (NO) synthase inhibitor, was injected into MSA prior to the injection of pilocarpine into MSA, producing an increase in salivary secretion due to the effect of pilocarpine. Sodium nitroprussiate (SNP) (30 microg/microl) was injected into MSA prior to the injection of pilocarpine into MSA attenuating the increase in salivary secretion induced by pilocarpine. Medial arterial pressure (MAP) increase after injections of pilocarpine into the MSA. L-NAME injected into the MSA prior to injection of pilocarpine into MSA increased the MAP. SNP injected into the MSA prior to pilocarpine attenuated the effect of pilocarpine on MAP. Pilocarpine (40 ug/ul) injected into the MAS induced an increase in sodium and urinary excretion. L-NAME injected prior to pilocarpine into the MSA increased the urinary sodium excretion and urinary volume induced by pilocarpine. SNP injected prior to pilocarpine into the MSA decreased the sodium excretion and urinary volume induced by pilocarpine. All these roles of pilocarpine depend on the release of nitric oxide into the MSA. We may also conclude that the MSA is involved with the cholinergic excitatory mechanism that induce salivary secretion, increase in MAP and increase in sodium excretion and urinary volume.

HIV-1 vaccine-induced T-cell responses cluster in epitope hotspots that differ from those induced in natural infection with HIV-1.

PubMed

Hertz, Tomer; Ahmed, Hasan; Friedrich, David P; Casimiro, Danilo R; Self, Steven G; Corey, Lawrence; McElrath, M Juliana; Buchbinder, Susan; Horton, Helen; Frahm, Nicole; Robertson, Michael N; Graham, Barney S; Gilbert, Peter

2013-01-01

Several recent large clinical trials evaluated HIV vaccine candidates that were based on recombinant adenovirus serotype 5 (rAd-5) vectors expressing HIV-derived antigens. These vaccines primarily elicited T-cell responses, which are known to be critical for controlling HIV infection. In the current study, we present a meta-analysis of epitope mapping data from 177 participants in three clinical trials that tested two different HIV vaccines: MRKAd-5 HIV and VRC-HIVAD014-00VP. We characterized the population-level epitope responses in these trials by generating population-based epitope maps, and also designed such maps using a large cohort of 372 naturally infected individuals. We used these maps to address several questions: (1) Are vaccine-induced responses randomly distributed across vaccine inserts, or do they cluster into immunodominant epitope hotspots? (2) Are the immunodominance patterns observed for these two vaccines in three vaccine trials different from one another? (3) Do vaccine-induced hotspots overlap with epitope hotspots induced by chronic natural infection with HIV-1? (4) Do immunodominant hotspots target evolutionarily conserved regions of the HIV genome? (5) Can epitope prediction methods be used to identify these hotspots? We found that vaccine responses clustered into epitope hotspots in all three vaccine trials and some of these hotspots were not observed in chronic natural infection. We also found significant differences between the immunodominance patterns generated in each trial, even comparing two trials that tested the same vaccine in different populations. Some of the vaccine-induced immunodominant hotspots were located in highly variable regions of the HIV genome, and this was more evident for the MRKAd-5 HIV vaccine. Finally, we found that epitope prediction methods can partially predict the location of vaccine-induced epitope hotspots. Our findings have implications for vaccine design and suggest a framework by which different vaccine candidates can be compared in early phases of evaluation.

Effects of beach-chair position and induced hypotension on cerebral oxygen saturation in patients undergoing arthroscopic shoulder surgery.

PubMed

Lee, Jae Hoon; Min, Kyeong Tae; Chun, Yong-Min; Kim, Eun Jung; Choi, Seung Ho

2011-07-01

We investigated the effects of the beach-chair position and induced hypotension on regional cerebral oxygen saturation (rSO(2)) in patients undergoing arthroscopic shoulder surgery by using near-infrared spectroscopy. Twenty-eight patients scheduled for arthroscopic shoulder surgery were enrolled prospectively. After induction of anesthesia, mechanical ventilation was controlled to maintain Paco(2) at 35 to 40 mm Hg. Anesthesia was maintained with sevoflurane and remifentanil. After radial artery cannulation, mean arterial pressure (MAP) was measured at the external auditory meatus level and maintained between 60 and 65 mm Hg. The rSO(2) was measured by use of near-infrared spectroscopy. MAP and rSO(2) were recorded at the following times: before induction (T(0)), immediately after induction (T(1) [baseline]), after beach-chair position (T(2)), immediately after induced hypotension (T(3)), 1 hour after induced hypotension (T(4)), and after supine position at the end of surgery (T(5)). Cerebral desaturation was defined as a reduction in rSO(2) to less than 80% of baseline value for 15 seconds or greater. A total of 27 patients were evaluated until the end of this study. The MAP at T(2) was significantly lower than that at T(1). The MAP values at T(3) and T(4) were significantly lower than those at T(1) and T(2). The rSO(2) at T(2) was significantly lower than that at T(1). Unlike the pattern of change in the MAP, there was no additional decrease in rSO(2) at T(3) and T(4). There were 2 patients who had an episode of cerebral desaturation. The beach-chair position combined with induced hypotension significantly decreases rSO(2) in patients undergoing shoulder arthroscopic surgery under general anesthesia. Level IV, study of nonconsecutive patients without consistently applied reference gold standard. Copyright © 2011 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

A Toposcopic Investigation of Brain Electrical Activity Induced by Motion Sickness

DTIC Science & Technology

1992-12-01

This hypothesis explains motion sickness symptoms as the body’s natural response when the infcr- mation transmitted by the eyes, the vestibular system...consisting of the summed pixel values of their respective sets. Each of these images are then converted to a map of the mean values and a map of the variances ...Statistical mapping requires a sizable normative database of maps, a signif - icant investment of resources (11:25). Location-by-location comparisons be

Andrographolide alleviates imiquimod-induced psoriasis in mice via inducing autophagic proteolysis of MyD88.

PubMed

Shao, Fenli; Tan, Tao; Tan, Yang; Sun, Yang; Wu, Xingxin; Xu, Qiang

2016-09-01

Psoriasis is a chronic inflammatory skin disease with excessive activation of toll-like receptors (TLRs), which play important roles in developing psoriasis. Targeting TLR signaling remains a challenge for treating psoriasis. Here, we found that andrographolide (Andro), a small-molecule natural product, alleviated imiquimod- but not interleukin 23 (IL-23)-induced psoriasis in mice with reducing expressions of IL-23 and IL-1β in the skin. The improvement in imiquimod-induced psoriasis by Andro was not observed in microtubule-associated protein 1 light chain 3 beta (MAP1LC3B) knockout mice. Furthermore, Andro inhibited mRNA expressions of IL-23, IL-6 and IL-1β but not CD80 and CD86 in bone-marrow derived dendritic cells (BMDCs) treated with lipopolysaccharide (LPS) in a MAP1LC3B-dependent manner. In addition, Andro inhibited imiquimod-induced mRNA expressions of IL-23, IL-6, IL-1β, CD80 and CD86 in BMDCs from mice. Interestingly, Andro induced a degradation of myeloid differentiation factor 88 (MyD88) and blocked the recruitment of TNF receptor-associated factor 6 (TRAF6) to MyD88 upon LPS stimulation in BMDCs from mice. Blockade of autophagic proteolysis using NH4Cl or MAP1LC3B(-/-) BMDCs abolished the Andro-induced MyD88 degradation. In conclusion, Andro controls activation of MyD88-dependent cytokines and alleviates psoriasis in mice via inducing autophagic proteolysis of MyD88, which could be a novel strategy to treat psoriasis. Copyright © 2016 Elsevier Inc. All rights reserved.

Intragenic Mapping of Chemically Induced ad-7 Mutants of Schizosaccharomyces pombe

PubMed Central

Loprieno, Nicola

1967-01-01

Thirty adenine-requiring ad-7 mutants of Schizosaccharomyces pombe, induced by ethylmethanesulfonate, methyl-methanesulfonate, and hydroxylamine and exhibiting low spontaneous reversion frequencies, were located by intragenic recombination analysis. Their identification as ad-7 mutants was assessed in relation to two previously mapped ad-7 mutants. Each mutant was found to occupy a distinct mutational site; the smallest recombination fraction observed between the two closest mutational sites was of the order of 0.5 × 10−6. PMID:6051345

ERK1/2 and p38 MAP kinases control prion protein fragment 90-231-induced astrocyte proliferation and microglia activation.

PubMed

Thellung, Stefano; Villa, Valentina; Corsaro, Alessandro; Pellistri, Francesca; Venezia, Valentina; Russo, Claudio; Aceto, Antonio; Robello, Mauro; Florio, Tullio

2007-11-01

Astrogliosis and microglial activation are a common feature during prion diseases, causing the release of chemoattractant and proinflammatory factors as well as reactive free radicals, involved in neuronal degeneration. The recombinant protease-resistant domain of the prion protein (PrP90-231) displays in vitro neurotoxic properties when refolded in a beta-sheet-rich conformer. Here, we report that PrP90-231 induces the secretion of several cytokines, chemokines, and nitric oxide (NO) release, in both type I astrocytes and microglial cells. PrP90-231 elicited in both cell types the activation of ERK1/2 MAP kinase that displays, in astrocytes, a rapid kinetics and a proliferative response. Conversely, in microglia, PrP90-231-dependent MAP kinase activation was delayed and long lasting, inducing functional activation and growth arrest. In microglial cells, NO release, dependent on the expression of the inducible NO synthase (iNOS), and the secretion of the chemokine CCL5 were Ca(2+) dependent and under the control of the MAP kinases ERK1/2 and p38: ERK1/2 inhibition, using PD98059, reduced iNOS expression, while p38 blockade by PD169316 inhibited CCL5 release. In summary, we demonstrate that glial cells are activated by extracellular misfolded PrP90-231 resulting in a proliferative/secretive response of astrocytes and functional activation of microglia, both dependent on MAP kinase activation. In particular, in microglia, PrP90-231 activated a complex signalling cascade involved in the regulation of NO and chemokine release. These data argue in favor of a causal role for misfolded prion protein in sustaining glial activation and, possibly, glia-mediated neuronal death.

Mitogen-activated protein kinase is required for the behavioral desensitization that occurs after repeated injections of angiotensin II

PubMed Central

Vento, Peter J.; Daniels, Derek

2013-01-01

Angiotensin II (AngII) acts on central angiotensin type 1 (AT1) receptors to increase water and saline intake. Prolonged exposure to AngII in cell culture models results in a desensitization of the AT1 receptor that is thought to involve receptor internalization, and a behavioral correlate of this desensitization has been shown in rats after repeated central injections of AngII. Specifically, rats given repeated injections of AngII drink less water than controls after a subsequent test injection of AngII. Under the same conditions, however, repeated injections of AngII have no effect on AngII-induced saline intake. Given earlier studies indicating that separate intracellular signaling pathways mediate AngII-induced water and saline intake, we hypothesized that the desensitization observed in rats may be incomplete, leaving the receptor able to activate mitogen-activated protein (MAP) kinases (ERK1/2), which play a role in AngII-induced saline intake without affecting water intake. In support of this hypothesis, we found no difference in MAP kinase phosphorylation after an AngII test injection in rats given prior treatment with repeated injections of vehicle, AngII, or Sar1,Ile4,Ile8-AngII (SII), an AngII analog that activates MAP kinase without G protein coupling. In addition, we found that pretreatment with the MAP kinase inhibitor U0126 completely blocked the desensitizing effect of repeated AngII injections on water intake. Furthermore, AngII-induced water intake was reduced similarly by repeated injections of AngII or SII. The results suggest that G protein-independent signaling is sufficient to produce behavioral desensitization of the angiotensin system and that the desensitization requires MAP kinase activation. PMID:22581747

Mitogen-activated protein kinase is required for the behavioural desensitization that occurs after repeated injections of angiotensin II.

PubMed

Vento, Peter J; Daniels, Derek

2012-12-01

Angiotensin II (Ang II) acts on central angiotensin type 1 (AT(1)) receptors to increase water and saline intake. Prolonged exposure to Ang II in cell culture models results in a desensitization of the AT(1) receptor that is thought to involve receptor internalization, and a behavioural correlate of this desensitization has been shown in rats after repeated central injections of Ang II. Specifically, rats given repeated injections of Ang II drink less water than control animals after a subsequent test injection of Ang II. In the same conditions, however, repeated injections of Ang II have no effect on Ang II-induced saline intake. Given earlier studies indicating that separate intracellular signalling pathways mediate Ang II-induced water and saline intake, we hypothesized that the desensitization observed in rats may be incomplete, leaving the receptor able to activate mitogen-activated protein (MAP) kinases (ERK1/2), which play a role in Ang II-induced saline intake without affecting water intake. In support of this hypothesis, we found no difference in MAP kinase phosphorylation after an Ang II test injection in rats given prior treatment with repeated injections of vehicle, Ang II or Sar(1),Ile(4),Ile(8)-Ang II (SII), an Ang II analogue that activates MAP kinase without G protein coupling. In addition, we found that pretreatment with the MAP kinase inhibitor U0126 completely blocked the desensitizing effect of repeated Ang II injections on water intake. Furthermore, Ang II-induced water intake was reduced to a similar extent by repeated injections of Ang II or SII. The results suggest that G protein-independent signalling is sufficient to produce behavioural desensitization of the angiotensin system and that the desensitization requires MAP kinase activation.

Genetic mapping of xenotropic murine leukemia virus-inducing loci in five mouse strains

PubMed Central

1980-01-01

A single mendelian gene was identified for induction of the endogenous xenotropic murine leukemia virus in five mouse strains (C57BL/10, C57L, C57BR, AKR, and BALB/c). This locus, designated Bxv-1, mapped to the same site on chromosome 1 in all strains: Id-1-Pep-3-[Bxv-1-Lp]. Thus, inducibility loci for xenotropic virus are more limited in number and chromosomal distribution than ecotropic inducibility loci. Virus expression in mice with Bxv-1 was induced by treatment of fibroblasts with 5-iododeoxyuridine or by exposure of spleen cells to a B cell mitogen, bacterial lipopolysaccharide. An analysis of the hamster X mouse somatic cell hybrids indicated that chromosome 1, alone, was sufficient for virus induction. PMID:6249881

Genetic mapping of xenotropic murine leukemia virus-inducing loci in five mouse strains.

PubMed

Kozak, C A; Rowe, W P

1980-07-01

A single mendelian gene was identified for induction of the endogenous xenotropic murine leukemia virus in five mouse strains (C57BL/10, C57L, C57BR, AKR, and BALB/c). This locus, designated Bxv-1, mapped to the same site on chromosome 1 in all strains: Id-1-Pep-3-[Bxv-1-Lp]. Thus, inducibility loci for xenotropic virus are more limited in number and chromosomal distribution than ecotropic inducibility loci. Virus expression in mice with Bxv-1 was induced by treatment of fibroblasts with 5-iododeoxyuridine or by exposure of spleen cells to a B cell mitogen, bacterial lipopolysaccharide. An analysis of the hamster X mouse somatic cell hybrids indicated that chromosome 1, alone, was sufficient for virus induction.

In-vitro mapping of E-fields induced near pacemaker leads by simulated MR gradient fields

PubMed Central

2009-01-01

Background Magnetic resonance imaging (MRI) of patients with implanted cardiac pacemakers is generally contraindicated but some clinicians condone scanning certain patients. We assessed the risk of inducing unintended cardiac stimulation by measuring electric fields (E) induced near lead tips by a simulated MRI gradient system. The objectives of this study are to map magnetically induced E near distal tips of leads in a saline tank to determine the spatial distribution and magnitude of E and compare them with E induced by a pacemaker pulse generator (PG). Methods We mapped magnetically induced E with 0.1 mm resolution as close as 1 mm from lead tips. We used probes with two straight electrodes (e.g. wire diameter of 0.2 mm separated by 0.9 mm). We generated magnetic flux density (B) with a Helmholtz coil throughout 0.6% saline in a 24 cm diameter tank with (dB/dt) of 1 T/sec (1 kHz sinusoidal waveform). Separately, we measured E near the tip of leads when connected to a PG set to a unipolar mode. Measurements were non-invasive (not altering the leads or PG under study). Results When scaled to 30 T/s (a clinically relevant value), magnetically-induced E exceeded the E produced by a PG. The magnetically-induced E only occurred when B was coincident with or within 15 msec of implantable pacemaker's pulse. Conclusions Potentially hazardous situations are possible during an MR scan due to gradient fields. Unintended stimulation can be induced via abandoned leads and leads connected to a pulse generator with loss of hermetic seal at the connector. Also, pacemaker-dependent patients can receive drastically altered pacing pulses. PMID:20003479

Stochastic maps, continuous approximation, and stable distribution

NASA Astrophysics Data System (ADS)

Kessler, David A.; Burov, Stanislav

2017-10-01

A continuous approximation framework for general nonlinear stochastic as well as deterministic discrete maps is developed. For the stochastic map with uncorelated Gaussian noise, by successively applying the Itô lemma, we obtain a Langevin type of equation. Specifically, we show how nonlinear maps give rise to a Langevin description that involves multiplicative noise. The multiplicative nature of the noise induces an additional effective force, not present in the absence of noise. We further exploit the continuum description and provide an explicit formula for the stable distribution of the stochastic map and conditions for its existence. Our results are in good agreement with numerical simulations of several maps.

Mapping of lead, magnesium and copper accumulation in plant tissues by laser-induced breakdown spectroscopy and laser-ablation inductively coupled plasma mass spectrometry

NASA Astrophysics Data System (ADS)

Kaiser, J.; Galiová, M.; Novotný, K.; Červenka, R.; Reale, L.; Novotný, J.; Liška, M.; Samek, O.; Kanický, V.; Hrdlička, A.; Stejskal, K.; Adam, V.; Kizek, R.

2009-01-01

Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) were utilized for mapping the accumulation of Pb, Mg and Cu with a resolution up to 200 μm in a up to cm × cm area of sunflower ( Helianthus annuus L.) leaves. The results obtained by LIBS and LA-ICP-MS are compared with the outcomes from Atomic Absorption Spectrometry (AAS) and Thin-Layer Chromatography (TLC). It is shown that laser-ablation based analytical methods can substitute or supplement these techniques mainly in the cases when a fast multi-elemental mapping of a large sample area is needed.

Particle visualization in high-power impulse magnetron sputtering. I. 2D density mapping

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

Britun, Nikolay, E-mail: nikolay.britun@umons.ac.be; Palmucci, Maria; Konstantinidis, Stephanos

2015-04-28

Time-resolved characterization of an Ar-Ti high-power impulse magnetron sputtering discharge has been performed. This paper deals with two-dimensional density mapping in the discharge volume obtained by laser-induced fluorescence imaging. The time-resolved density evolution of Ti neutrals, singly ionized Ti atoms (Ti{sup +}), and Ar metastable atoms (Ar{sup met}) in the area above the sputtered cathode is mapped for the first time in this type of discharges. The energetic characteristics of the discharge species are additionally studied by Doppler-shift laser-induced fluorescence imaging. The questions related to the propagation of both the neutral and ionized discharge particles, as well as to theirmore » spatial density distributions, are discussed.« less

High-level expression and deuteration of sperm whale myoglobin: A study of its solvent structure by X-ray and neutron diffraction methods

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

Shu, F.; Ramakrishnan, V.; Schoenborn, B.P.

1994-12-31

Neutron diffraction has become one of the best ways to study light atoms, such as hydrogens. Hydrogen however has a negative coherent scattering factor, and a large incoherent scattering factor, while deuterium has virtually no incoherent scattering, but a large positive coherent scattering factor. Beside causing high background due to its incoherent scattering, the negative coherent scattering of hydrogen tends to cancel out the positive contribution from other atoms in a neutron density map. Therefore a fully deuterated sample will yield better diffraction data with stronger density in the hydrogen position. On this basis, a sperm whale myoglobin gene modifiedmore » to include part of the A cII protein gene has been cloned into the T7 expression system. Milligram amounts of fully deuterated holo-myoglobin have been obtained and used for crystallization. The synthetic sperm whale myoglobin crystallized in P2{sub 1} space group isomorphous with the native protein crystal. A complete X-ray diffraction dataset at 1.5{Angstrom} has been collected. This X-ray dataset, and a neutron data set collected previously on a protonated carbon-monoxymyoglobin crystal have been used for solvent structure studies. Both X-ray and neutron data have shown that there are ordered hydration layers around the protein surface. Solvent shell analysis on the neutron data further has shown that the first hydration layer behaves differently around polar and apolar regions of the protein surface. Finally, the structure of per-deuterated myoglobin has been refined using all reflections to a R factor of 17%.« less

Preliminary X-ray diffraction analysis of CfaA, a molecular chaperone essential for the assembly of CFA/I fimbriae of human enterotoxigenic Escherichia coli.

PubMed

Bao, Rui; Esser, Lothar; Poole, Steven; McVeigh, Annette; Chen, Yu Xing; Savarino, Stephen J; Xia, Di

2014-02-01

Understanding of pilus bioassembly in Gram-negative bacteria stems mainly from studies of P pili and type 1 fimbriae of uropathogenic Escherichia coli, which are mediated by the classic chaperone-usher pathway (CUP). However, CFA/I fimbriae, a class 5 fimbria and intestinal colonization factor for enterotoxigenic E. coli (ETEC), are proposed to assemble via the alternate chaperone pathway (ACP). Both CUP and ACP fimbrial bioassembly pathways require the function of a periplasmic chaperone, but their corresponding proteins share very low similarity in primary sequence. Here, the crystallization of the CFA/I periplasmic chaperone CfaA by the hanging-drop vapor-diffusion method is reported. X-ray diffraction data sets were collected from a native CfaA crystal to 2 Å resolution and to 1.8 and 2.8 Å resolution, respectively, from a lead and a platinum derivative. These crystals displayed the symmetry of space group C2, with unit-cell parameters a = 103.6, b = 28.68, c = 90.60 Å, β = 119.7°. Initial phases were derived from multiple isomorphous replacement with anomalous scattering experiments using the data from the platinum and lead derivatives. This resulted in an interpretable electron-density map showing one CfaA molecule in an asymmetric unit. Sequence assignments were aided by anomalous signals from the heavy-atom derivatives. Refinement of the atomic model of CfaA is ongoing, which is expected to further understanding of the essential aspects and allowable variations in tertiary structure of the greater family of chaperones involved in chaperone-usher mediated bioassembly.

Force, velocity, and work: The effects of different contexts on students' understanding of vector concepts using isomorphic problems

NASA Astrophysics Data System (ADS)

Barniol, Pablo; Zavala, Genaro

2014-12-01

In this article we compare students' understanding of vector concepts in problems with no physical context, and with three mechanics contexts: force, velocity, and work. Based on our "Test of Understanding of Vectors," a multiple-choice test presented elsewhere, we designed two isomorphic shorter versions of 12 items each: a test with no physical context, and a test with mechanics contexts. For this study, we administered the items twice to students who were finishing an introductory mechanics course at a large private university in Mexico. The first time, we administered the two 12-item tests to 608 students. In the second, we only tested the items for which we had found differences in students' performances that were difficult to explain, and in this case, we asked them to show their reasoning in written form. In the first administration, we detected no significant difference between the medians obtained in the tests; however, we did identify significant differences in some of the items. For each item we analyze the type of difference found between the tests in the selection of the correct answer, the most common error on each of the tests, and the differences in the selection of incorrect answers. We also investigate the causes of the different context effects. Based on these analyses, we establish specific recommendations for the instruction of vector concepts in an introductory mechanics course. In the Supplemental Material we include both tests for other researchers studying vector learning, and for physics teachers who teach this material.

Cohomological rigidity of manifolds defined by 3-dimensional polytopes

NASA Astrophysics Data System (ADS)

Buchstaber, V. M.; Erokhovets, N. Yu.; Masuda, M.; Panov, T. E.; Park, S.

2017-04-01

A family of closed manifolds is said to be cohomologically rigid if a cohomology ring isomorphism implies a diffeomorphism for any two manifolds in the family. Cohomological rigidity is established here for large families of 3-dimensional and 6-dimensional manifolds defined by 3-dimensional polytopes. The class \\mathscr{P} of 3-dimensional combinatorial simple polytopes P different from tetrahedra and without facets forming 3- and 4-belts is studied. This class includes mathematical fullerenes, that is, simple 3- polytopes with only 5-gonal and 6-gonal facets. By a theorem of Pogorelov, any polytope in \\mathscr{P} admits in Lobachevsky 3-space a right-angled realisation which is unique up to isometry. Our families of smooth manifolds are associated with polytopes in the class \\mathscr{P}. The first family consists of 3-dimensional small covers of polytopes in \\mathscr{P}, or equivalently, hyperbolic 3-manifolds of Löbell type. The second family consists of 6-dimensional quasitoric manifolds over polytopes in \\mathscr{P}. Our main result is that both families are cohomologically rigid, that is, two manifolds M and M' from either family are diffeomorphic if and only if their cohomology rings are isomorphic. It is also proved that if M and M' are diffeomorphic, then their corresponding polytopes P and P' are combinatorially equivalent. These results are intertwined with classical subjects in geometry and topology such as the combinatorics of 3-polytopes, the Four Colour Theorem, aspherical manifolds, a diffeomorphism classification of 6-manifolds, and invariance of Pontryagin classes. The proofs use techniques of toric topology. Bibliography: 69 titles.

Super (a*, d*)-ℋ-antimagic total covering of second order of shackle graphs

NASA Astrophysics Data System (ADS)

Hesti Agustin, Ika; Dafik; Nisviasari, Rosanita; Prihandini, R. M.

2017-12-01

Let H be a simple and connected graph. A shackle of graph H, denoted by G = shack(H, v, n), is a graph G constructed by non-trivial graphs H 1, H 2, …, H n such that, for every 1 ≤ s, t ≤ n, H s and Ht have no a common vertex with |s - t| ≥ 2 and for every 1 ≤ i ≤ n - 1, Hi and H i+1 share exactly one common vertex v, called connecting vertex, and those k - 1 connecting vertices are all distinct. The graph G is said to be an (a*, d*)-H-antimagic total graph of second order if there exist a bijective function f : V(G) ∪ E(G) → {1, 2, …, |V(G)| + |E(G)|} such that for all subgraphs isomorphic to H, the total H-weights W(H)=\\displaystyle {\\sum }v\\in V(H)f(v)+\\displaystyle {\\sum }e\\in E(H)f(e) form an arithmetic sequence of second order of \\{a* ,a* +d* ,a* +3d* ,a* +6d* ,\\ldots ,a* +(\\frac{{n}2-n}{2})d* \\}, where a* and d* are positive integers and n is the number of all subgraphs isomorphic to H. An (a*, d*)-H-antimagic total labeling of second order f is called super if the smallest labels appear in the vertices. In this paper, we study a super (a*, d*)-H antimagic total labeling of second order of G = shack(H, v, n) by using a partition technique of second order.

A Ga2O3 underlayer as an isomorphic template for ultrathin hematite films toward efficient photoelectrochemical water splitting.

PubMed

Hisatomi, Takashi; Brillet, Jérémie; Cornuz, Maurin; Le Formal, Florian; Tétreault, Nicolas; Sivula, Kevin; Grätzel, Michael

2012-01-01

Hematite photoanodes for photoelectrochemical (PEC) water splitting are often fabricated as extremely-thin films to minimize charge recombination because of the short diffusion lengths of photoexcited carriers. However, poor crystallinity caused by structural interaction with a substrate negates the potential of ultrathin hematite photoanodes. This study demonstrates that ultrathin Ga2O3 underlayers, which were deposited on conducting substrates prior to hematite layers by atomic layer deposition, served as an isomorphic (corundum-type) structural template for ultrathin hematite and improved the photocurrent onset of PEC water splitting by 0.2 V. The benefit from Ga2O3 underlayers was most pronounced when the thickness of the underlayer was approximately 2 nm. Thinner underlayers did not work effectively as a template presumably because of insufficient crystallinity of the underlayer, while thicker ones diminished the PEC performance of hematite because the underlayer prevented electron injection from hematite to a conductive substrate due to the large conduction band offset. The enhancement of PEC performance by a Ga2O3 underlayer was more significant for thinner hematite layers owing to greater margins for improving the crystallinity of ultrathin hematite. It was confirmed that a Ga2O3 underlayer was applicable to a rough conducting substrate loaded with Sb-doped SnO2 nanoparticles, improving the photocurrent by a factor of 1.4. Accordingly, a Ga2O3 underlayer could push forward the development of host-guest-type nanocomposites consisting of highly-rough substrates and extremely-thin hematite absorbers.

Characterization of a Thermo-Inducible Chlorophyll-Deficient Mutant in Barley.

PubMed

Wang, Rong; Yang, Fei; Zhang, Xiao-Qi; Wu, Dianxin; Tan, Cong; Westcott, Sharon; Broughton, Sue; Li, Chengdao; Zhang, Wenying; Xu, Yanhao

2017-01-01

Leaf color is an important trait for not only controlling crop yield but also monitoring plant status under temperature stress. In this study, a thermo-inducible chlorophyll-deficient mutant, named V-V-Y, was identified from a gamma-radiated population of the barley variety Vlamingh. The leaves of the mutant were green under normal growing temperature but turned yellowish under high temperature in the glasshouse experiment. The ratio of chlorophyll a and chlorophyll b in the mutant declined much faster in the first 7-9 days under heat treatment. The leaves of V-V-Y turned yellowish but took longer to senesce under heat stress in the field experiment. Genetic analysis indicated that a single nuclear gene controlled the mutant trait. The mutant gene ( vvy ) was mapped to the long arm of chromosome 4H between SNP markers 1_0269 and 1_1531 with a genetic distance of 2.2 cM and a physical interval of 9.85 Mb. A QTL for grain yield was mapped to the same interval and explained 10.4% of the yield variation with a LOD score of 4. This QTL is coincident with the vvy gene interval that is responsible for the thermo-inducible chlorophyll-deficient trait. Fine mapping, based on the barley reference genome sequence, further narrowed the vvy gene to a physical interval of 0.428 Mb with 11 annotated genes. This is the first report of fine mapping a thermo-inducible chlorophyll-deficient gene in barley.

p53 regulates ERK1/2/CREB cascade via a novel SASH1/MAP2K2 crosstalk to induce hyperpigmentation.

PubMed

Zhou, Ding'an; Kuang, Zhongshu; Zeng, Xing; Wang, Ke; Ma, Jiangshu; Luo, Huangchao; Chen, Mei; Li, Yan; Zeng, Jiawei; Li, Shu; Luan, Fujun; He, Yong; Dai, Hongying; Liu, Beizhong; Li, Hui; He, Lin; Xing, Qinghe

2017-10-01

We previously reported that three point mutations in SASH1 and mutated SASH1 promote melanocyte migration in dyschromatosis universalis hereditaria (DUH) and a novel p53/POMC/Gαs/SASH1 autoregulatory positive feedback loop is regulated by SASH1 mutations to induce pathological hyperpigmentation phenotype. However, the underlying mechanism of molecular regulation to cause this hyperpigmentation disorder still remains unclear. In this study, we aimed to investigate the molecular mechanism undergirding hyperpigmentation in the dyschromatosis disorder. Our results revealed that SASH1 binds with MAP2K2 and is induced by p53-POMC-MC1R signal cascade to enhance the phosphorylation level of ERK1/2 and CREB. Moreover, increase in phosphorylated ERK1/2 and CREB levels and melanogenesis-specific molecules is induced by mutated SASH1 alleles. Together, our results suggest that a novel SASH1/MAP2K2 crosstalk connects ERK1/2/CREB cascade with p53-POMC-MC1R cascade to cause hyperpigmentation phenotype of DUH. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Evidence for hysteresis in the cerebral pressure-flow relationship in healthy men.

PubMed

Brassard, Patrice; Ferland-Dutil, Hélène; Smirl, Jonathan D; Paquette, Myriam; Le Blanc, Olivier; Malenfant, Simon; Ainslie, Philip N

2017-04-01

The cerebrovasculature is more efficient at compensating for pharmacologically induced transient hypertension versus transient hypotension. Whether this phenomenon exists during nonpharmacologically induced hypertension and hypotension is currently unknown. We compared the percent change in mean velocity in the middle cerebral artery (MCAvmean) per percent change in mean arterial pressure (MAP) (%ΔMCAVmean/%ΔMAP) during transient hypertension and hypotension induced during squat-stand maneuvers performed at 0.05 Hz (20-s cycles) and 0.10 Hz (10-s cycles) in 58 male volunteers. %ΔMCAvmean/%ΔMAP was attenuated by 25% ( P = 0.03, 0.05 Hz) and 47% ( P < 0.0001, 0.10 Hz) during transient hypertension versus hypotension. Thus, these findings indicate that the brain in healthy men is better adapted to compensate for physiologically relevant transient hypertension than hypotension. NEW & NOTEWORTHY The novel finding of this study is that the change in middle cerebral artery mean flow velocity is attenuated during hypertension compared with hypotension physiologically induced by oscillations in blood pressure in men. These results support that the human brain is more effective at compensating for transient hypertension than hypotension. Copyright © 2017 the American Physiological Society.

CR108, a novel vitamin K3 derivative induces apoptosis and breast tumor inhibition by reactive oxygen species and mitochondrial dysfunction.

PubMed

Yang, Chun-Ru; Liao, Wei-Siang; Wu, Ya-Hui; Murugan, Kaliyappan; Chen, Chinpiao; Chao, Jui-I

2013-12-15

Vitamin K3 derivatives have been shown to exert anticancer activities. Here we show a novel vitamin K3 derivative (S)-2-(2-hydroxy-3-methylbutylthio)naphthalene-1,4-dione, which is named as CR108 that induces apoptosis and tumor inhibition through reactive oxygen species (ROS) and mitochondrial dysfunction in human breast cancer. CR108 is more effective on the breast cancer cell death than other vitamin K3 derivatives. Moreover, CR108 induced apoptosis in both the non-HER-2-overexpressed MCF-7 and HER-2-overexpressed BT-474 breast cancer cells. CR108 caused the loss of mitochondrial membrane potential, cytochrome c released from mitochondria to cytosol, and cleaved PARP proteins for apoptosis induction. CR108 markedly increased ROS levels in breast cancer cells. N-acetylcysteine (NAC), a general ROS scavenger, completely blocked the CR108-induced ROS levels, mitochondrial dysfunction and apoptosis. Interestingly, CR108 increased the phosphorylation of p38 MAP kinase but conversely inhibited the survivin protein expression. NAC treatment prevented the activation of p38 MAP kinase and rescued the survivin protein levels. SB202190, a specific p38 MAP kinase inhibitor, recovered the survivin protein levels and attenuated the cytotoxicity of CR108-treated cells. Furthermore, CR108 inhibited the xenografted human breast tumor growth in nude mice. Together, we demonstrate that CR108 is a novel vitamin K3 derivative that induces apoptosis and tumor inhibition by ROS production and mitochondrial dysfunction and associates with the phosphorylation of p38 MAP kinase and the inhibition of survivin in the human breast cancer. © 2013.

Sun-induced fluorescence - a new probe of photosynthesis: First maps from the imaging spectrometer HyPlant.

PubMed

Rascher, U; Alonso, L; Burkart, A; Cilia, C; Cogliati, S; Colombo, R; Damm, A; Drusch, M; Guanter, L; Hanus, J; Hyvärinen, T; Julitta, T; Jussila, J; Kataja, K; Kokkalis, P; Kraft, S; Kraska, T; Matveeva, M; Moreno, J; Muller, O; Panigada, C; Pikl, M; Pinto, F; Prey, L; Pude, R; Rossini, M; Schickling, A; Schurr, U; Schüttemeyer, D; Verrelst, J; Zemek, F

2015-12-01

Variations in photosynthesis still cause substantial uncertainties in predicting photosynthetic CO2 uptake rates and monitoring plant stress. Changes in actual photosynthesis that are not related to greenness of vegetation are difficult to measure by reflectance based optical remote sensing techniques. Several activities are underway to evaluate the sun-induced fluorescence signal on the ground and on a coarse spatial scale using space-borne imaging spectrometers. Intermediate-scale observations using airborne-based imaging spectroscopy, which are critical to bridge the existing gap between small-scale field studies and global observations, are still insufficient. Here we present the first validated maps of sun-induced fluorescence in that critical, intermediate spatial resolution, employing the novel airborne imaging spectrometer HyPlant. HyPlant has an unprecedented spectral resolution, which allows for the first time quantifying sun-induced fluorescence fluxes in physical units according to the Fraunhofer Line Depth Principle that exploits solar and atmospheric absorption bands. Maps of sun-induced fluorescence show a large spatial variability between different vegetation types, which complement classical remote sensing approaches. Different crop types largely differ in emitting fluorescence that additionally changes within the seasonal cycle and thus may be related to the seasonal activation and deactivation of the photosynthetic machinery. We argue that sun-induced fluorescence emission is related to two processes: (i) the total absorbed radiation by photosynthetically active chlorophyll; and (ii) the functional status of actual photosynthesis and vegetation stress. © 2015 John Wiley & Sons Ltd.

Regulation of choroidal blood flow during combined changes in intraocular pressure and arterial blood pressure.

PubMed

Polska, Elzbieta; Simader, Christian; Weigert, Günter; Doelemeyer, Arno; Kolodjaschna, Julia; Scharmann, Ole; Schmetterer, Leopold

2007-08-01

To test the hypothesis that human choroidal blood flow (ChBF) may depend, not only on ocular perfusion pressure (OPP), but also on absolute mean arterial pressure (MAP) and intraocular pressure (IOP). There were two study days in an open design. On the first day, OPP was varied by elevating IOP during a squatting-induced increase in MAP (28 subjects). On the second day, only the IOP was increased (17 subjects). IOP was raised in stepwise increments by using the suction cup Subfoveal ChBF (laser Doppler flowmetry), MAP, and IOP were assessed, and OPP was calculated as (2/3)(MAP - IOP). For correlation analysis, data from all subjects were pooled according to IOP and MAP, and correlation analyses were performed. When data from study day 1 were grouped according to IOP, no correlation was observed between ChBF and MAP; but ChBFs were lower, the higher the IOP (P < 0.001). When data were grouped according to MAP, a significant correlation was found between ChBF and IOP (P < 0.001), but correlations were independent of MAP. When data of study day 2 were pooled according to IOP, a correlation between ChBF and OPP was seen only at IOP > 40 mm Hg (P < 0.05). The data confirm previously published observations that the choroid shows some autoregulatory capacity during changes in OPP. In addition, the data indicate that the choroid regulates its blood flow better during exercise-induced changes in MAP than during an experimental increase in IOP.

Regulation of cotton (Gossypium hirsutum) drought responses by mitogen-activated protein (MAP) kinase cascade-mediated phosphorylation of GhWRKY59.

PubMed

Li, Fangjun; Li, Maoying; Wang, Ping; Cox, Kevin L; Duan, Liusheng; Dever, Jane K; Shan, Libo; Li, Zhaohu; He, Ping

2017-09-01

Drought is a key limiting factor for cotton (Gossypium spp.) production, as more than half of the global cotton supply is grown in regions with high water shortage. However, the underlying mechanism of the response of cotton to drought stress remains elusive. By combining genome-wide transcriptome profiling and a loss-of-function screen using virus-induced gene silencing, we identified Gossypium hirsutum GhWRKY59 as an important transcription factor that regulates the drought stress response in cotton. Biochemical and genetic analyses revealed a drought stress-activated mitogen-activated protein (MAP) kinase cascade consisting of GhMAP3K15-Mitogen-activated Protein Kinase Kinase 4 (GhMKK4)-Mitogen-activated Protein Kinase 6 (GhMPK6) that directly phosphorylates GhWRKY59 at residue serine 221. Interestingly, GhWRKY59 is required for dehydration-induced expression of GhMAPK3K15, constituting a positive feedback loop of GhWRKY59-regulated MAP kinase activation in response to drought stress. Moreover, GhWRKY59 directly binds to the W-boxes of DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN 2 (GhDREB2), which encodes a dehydration-inducible transcription factor regulating the plant hormone abscisic acid (ABA)-independent drought response. Our study identified a complete MAP kinase cascade that phosphorylates and activates a key WRKY transcription factor, and elucidated a regulatory module, consisting of GhMAP3K15-GhMKK4-GhMPK6-GhWRKY59-GhDREB2, that is involved in controlling the cotton drought response. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Seismically induced landslides: current research by the US Geological Survey.

USGS Publications Warehouse

Harp, E.L.; Wilson, R.C.; Keefer, D.K.; Wieczorek, G.F.

1986-01-01

We have produced a regional seismic slope-stability map and a probabilistic prediction of landslide distribution from a postulated earthquake. For liquefaction-induced landslides, in situ measurements of seismically induced pore-water pressures have been used to establish an elastic model of pore pressure generation. -from Authors

Mycobacterium paratuberculosis, Mycobacterium smegmatis, and lipopolysaccharide induce different transcriptional and post-transcriptional regulation of the IRG1 gene in murine macrophages.

PubMed

Basler, Tina; Jeckstadt, Sabine; Valentin-Weigand, Peter; Goethe, Ralph

2006-03-01

Mycobacterium avium subspecies paratuberculosis (MAP) causes a chronic enteritis in ruminants. In addition, MAP is presently the most favored pathogen linked to Crohn's disease. In this study, we were interested in dissecting the molecular mechanisms of macrophage activation or deactivation after infection with MAP. By subtractive hybridization of cDNAs, we identified the immune-responsive gene 1 (IRG1), which was expressed substantially higher in lipopolysaccharide (LPS)-stimulated than in MAP-infected murine macrophage cell lines. A nuclear run-on transcription assay revealed that the IRG1 gene was activated transcriptionally in LPS-stimulated and MAP-infected macrophages with higher expression in LPS-stimulated cells. Analysis of post-transcriptional regulation demonstrated that IRG1 mRNA stability was increased in LPS-stimulated but not in MAP-infected macrophages. Furthermore, IRG1 gene expression of macrophages infected with the nonpathogenic Mycobacterium smegmatis differed from those of LPS-stimulated and MAP-infected macrophages. At 2 h postinfection, M. smegmatis-induced IRG1 gene expression was as low as in MAP-infected, and 8 h postinfection, it increased nearly to the level in LPS-stimulated macrophages. Transient transfection experiments revealed similar IRG1 promoter activities in MAP- and M. smegmatis-infected cells. Northern analysis demonstrated increased IRG1 mRNA stability in M. smegmatis-infected macrophages. IRG1 mRNA stabilization was p38 mitogen-activated protein kinase-independent. Inhibition of protein synthesis revealed that constitutively expressed factors seemed to be responsible for IRG1 mRNA destabilization. Thus, our data demonstrate that transcriptional and post-transcriptional mechanisms are responsible for a differential IRG1 gene expression in murine macrophages treated with LPS, MAP, and M. smegmatis.

Calculation of catalyst crust thickness from full elemental laser-induced breakdown spectroscopy images

NASA Astrophysics Data System (ADS)

Sorbier, L.; Trichard, F.; Moncayo, S.; Lienemann, C. P.; Motto-Ros, V.

2018-01-01

We propose a methodology to compute the crust thickness of an element in an egg-shell catalyst from a two-dimensional elemental map. The methodology handles two important catalyst shapes: infinite extrudates of arbitrary section and spheres. The methodology is validated with synthetic analytical profiles on simple shapes (cylinder and sphere). Its relative accuracy is shown close to few percent with a decrease inversely proportional to the square root of the number of sampled pixels. The crust thickness obtained by this method from quantitative Pd maps acquired by laser-induced breakdown spectroscopy are comparable with values obtained from electron-probe microanalysis profiles. Some discrepancies are found and are explained by the heterogeneity of the crust thickness within a grain. As a full map is more representative than a single profile, fast mapping and the methodology exposed in this paper are expected to become valuable tools for the development of new generations of egg-shell deposited catalysts.

EIT-based fabric pressure sensing.

PubMed

Yao, A; Yang, C L; Seo, J K; Soleimani, M

2013-01-01

This paper presents EIT-based fabric sensors that aim to provide a pressure mapping using the current carrying and voltage sensing electrodes attached to the boundary of the fabric patch. Pressure-induced shape change over the sensor area makes a change in the conductivity distribution which can be conveyed to the change of boundary current-voltage data. This boundary data is obtained through electrode measurements in EIT system. The corresponding inverse problem is to reconstruct the pressure and deformation map from the relationship between the applied current and the measured voltage on the fabric boundary. Taking advantage of EIT in providing dynamical images of conductivity changes due to pressure induced shape change, the pressure map can be estimated. In this paper, the EIT-based fabric sensor was presented for circular and rectangular sensor geometry. A stretch sensitive fabric was used in circular sensor with 16 electrodes and a pressure sensitive fabric was used in a rectangular sensor with 32 electrodes. A preliminary human test was carried out with the rectangular sensor for foot pressure mapping showing promising results.

Graded levels of FGF protein span the midbrain and can instruct graded induction and repression of neural mapping labels

PubMed Central

Chen, Yao; Mohammadi, Moosa; Flanagan, John G.

2009-01-01

Summary Graded guidance labels are widely used in neural map formation, but it is not well understood which potential strategy leads to their graded expression. In midbrain tectal map development, FGFs can induce an entire midbrain, but their protein distribution is unclear, nor is it known whether they may act instructively to produce graded gene expression. Using a receptor-alkaline phosphatase fusion probe, we find a long-range posterior>anterior FGF protein gradient spanning the midbrain. Heparan sulfate proteoglycan (HSPG) is required for this gradient. To test whether graded FGF concentrations can instruct graded gene expression, a quantitative tectal explant assay was developed. Engrailed-2 and ephrin-As, normally in posterior>anterior tectal gradients, showed graded upregulation. Moreover, EphAs, normally in anterior>posterior countergradients, showed coordinately graded downregulation. These results provide a mechanism to establish graded mapping labels, and more generally provide a developmental strategy to coordinately induce a structure and pattern its cell properties in gradients. PMID:19555646

Cyanidin-3-glucoside inhibits UVB-induced oxidative damage and inflammation by regulating MAP kinase and NF-κB signaling pathways in SKH-1 hairless mice skin.

PubMed

Pratheeshkumar, Poyil; Son, Young-Ok; Wang, Xin; Divya, Sasidharan Padmaja; Joseph, Binoy; Hitron, John Andrew; Wang, Lei; Kim, Donghern; Yin, Yuanqin; Roy, Ram Vinod; Lu, Jian; Zhang, Zhuo; Wang, Yitao; Shi, Xianglin

2014-10-01

Skin cancer is one of the most commonly diagnosed cancers in the United States. Exposure to ultraviolet-B (UVB) radiation induces inflammation and photocarcinogenesis in mammalian skin. Cyanidin-3-glucoside (C3G), a member of the anthocyanin family, is present in various vegetables and fruits especially in edible berries, and displays potent antioxidant and anticarcinogenic properties. In this study, we have assessed the in vivo effects of C3G on UVB irradiation induced chronic inflammatory responses in SKH-1 hairless mice, a well-established model for UVB-induced skin carcinogenesis. Here, we show that C3G inhibited UVB-induced skin damage and inflammation in SKH-1 hairless mice. Our results indicate that C3G inhibited glutathione depletion, lipid peroxidation and myeloperoxidation in mouse skin by chronic UVB exposure. C3G significantly decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-6 and TNF-α, associated with cutaneous inflammation. Likewise, UVB-induced inflammatory responses were diminished by C3G as observed by a remarkable reduction in the levels of phosphorylated MAP kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, C3G also decreased UVB-induced cyclooxygenase-2 (COX-2), PGE2 and iNOS levels, which are well-known key mediators of inflammation and cancer. Treatment with C3G inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mice skin. Immunofluorescence assay revealed that topical application of C3G inhibited the expression of 8-hydroxy-2'-deoxyguanosine, proliferating cell nuclear antigen, and cyclin D1 in chronic UVB exposed mouse skin. Collectively, these data indicates that C3G can provide substantial protection against the adverse effects of UVB radiation by modulating UVB-induced MAP kinase and NF-κB signaling pathways. Copyright © 2014 Elsevier Inc. All rights reserved.

Cyanidin-3-Glucoside inhibits UVB-induced oxidative damage and inflammation by regulating MAP kinase and NF-κB signalling pathways in SKH-1 hairless mice skin

PubMed Central

Pratheeshkumar, Poyil; Son, Young-Ok; Wang, Xin; Divya, Sasidharan Padmaja; Joseph, Binoy; Hitron, John Andrew; Wang, Lei; Kim, Donghern; Yin, Yuanqin; Roy, Ram Vinod; Lu, Jian; Zhang, Zhuo; Wang, Yitao; Shi, Xianglin

2015-01-01

Skin cancer is one of the most commonly diagnosed cancers in the United States. Exposure to ultraviolet-B (UVB) radiation induces inflammation and photocarcinogenesis in mammalian skin. Cyanidin-3-Glucoside (C3G), a member of the anthocyanin family, is present in various vegetables and fruits especially in edible berries, and displays potent antioxidant and anticarcinogenic properties. In this study, we have assessed the in vivo effects of C3G on UVB irradiation induced chronic inflammatory responses in SKH-1 hairless mice, a well-established model for UVB-induced skin carcinogenesis. Here, we show that C3G inhibited UVB-induced skin damage and inflammation in SKH-1 hairless mice. Our results indicate that C3G inhibited glutathione depletion, lipid peroxidation and myeloperoxidation in mouse skin by chronic UVB exposure. C3G significantly decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-6 and TNF-α, associated with cutaneous inflammation. Likewise, UVB-induced inflammatory responses were diminished by C3G as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, C3G also decreased UVB-induced cyclooxygenase-2 (COX-2), PGE2 and iNOS levels, which are well-known key mediators of inflammation and cancer. Treatment with C3G inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mice skin. Immunofluorescence assay revealed that topical application of C3G inhibited the expression of 8-hydroxy-2′-deoxyguanosine, proliferating cell nuclear antigen, and cyclin D1 in chronic UVB exposed mouse skin. Collectively, these data indicates that C3G can provide substantial protection against the adverse effects of UVB radiation by modulating UVB-induced MAP kinase and NF-κB signaling pathways. PMID:25062774

Marginal deformations of heterotic G 2 sigma models

NASA Astrophysics Data System (ADS)

Fiset, Marc-Antoine; Quigley, Callum; Svanes, Eirik Eik

2018-02-01

Recently, the infinitesimal moduli space of heterotic G 2 compactifications was described in supergravity and related to the cohomology of a target space differential. In this paper we identify the marginal deformations of the corresponding heterotic nonlinear sigma model with cohomology classes of a worldsheet BRST operator. This BRST operator is nilpotent if and only if the target space geometry satisfies the heterotic supersymmetry conditions. We relate this to the supergravity approach by showing that the corresponding cohomologies are indeed isomorphic. We work at tree-level in α' perturbation theory and study general geometries, in particular with non-vanishing torsion.

Virasoro algebra in the KN algebra; Bosonic string with fermionic ghosts on Riemann surfaces

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

Koibuchi, H.

1991-10-10

In this paper the bosonic string model with fermionic ghosts is considered in the framework of the KN algebra. The authors' attentions are paid to representations of KN algebra and a Clifford algebra of the ghosts. The authors show that a Virasoro-like algebra is obtained from KN algebra when KN algebra has certain antilinear anti-involution, and that it is isomorphic to the usual Virasoro algebra. The authors show that there is an expected relation between a central charge of this Virasoro-like algebra and an anomaly of the combined system.

An algebraic structure of discrete-time biaffine systems

NASA Technical Reports Server (NTRS)

Tarn, T.-J.; Nonoyama, S.

1979-01-01

New results on the realization of finite-dimensional, discrete-time, internally biaffine systems are presented in this paper. The external behavior of such systems is described by multiaffine functions and the state space is constructed via Nerode equivalence relations. We prove that the state space is an affine space. An algorithm which amounts to choosing a frame for the affine space is presented. Our algorithm reduces in the linear and bilinear case to a generalization of algorithms existing in the literature. Explicit existence criteria for span-canonical realizations as well as an affine isomorphism theorem are given.

Conformal and projective symmetries in Newtonian cosmology

NASA Astrophysics Data System (ADS)

Duval, C.; Gibbons, G. W.; Horváthy, P. A.

2017-02-01

Definitions of non-relativistic conformal transformations are considered both in the Newton-Cartan and in the Kaluza-Klein-type Eisenhart/Bargmann geometrical frameworks. The symmetry groups that come into play are exemplified by the cosmological, and also the Newton-Hooke solutions of Newton's gravitational field equations. It is shown, in particular, that the maximal symmetry group of the standard cosmological model is isomorphic to the 13-dimensional conformal-Newton-Cartan group whose conformal-Bargmann extension is explicitly worked out. Attention is drawn to the appearance of independent space and time dilations, in contrast with the Schrödinger group or the Conformal Galilei Algebra.

Ionic liquid-templated preparation of mesoporous silica embedded with nanocrystalline sulfated zirconia

NASA Astrophysics Data System (ADS)

Ward, Antony J.; Pujari, Ajit A.; Costanzo, Lorenzo; Masters, Anthony F.; Maschmeyer, Thomas

2011-12-01

A series of mesoporous silicas impregnated with nanocrystalline sulphated zirconia was prepared by a sol-gel process using an ionic liquid-templated route. The physicochemical properties of the mesoporous sulphated zirconia materials were studied using characterisation techniques such as inductively coupled optical emission spectroscopy, X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray microanalysis, elemental analysis and X-ray photoelectron spectroscopy. Analysis of the new silicas indicates isomorphous substitution of silicon with zirconium and reveals the presence of extremely small (< 10 nm) polydispersed zirconia nanoparticles in the materials with zirconium loadings from 27.77 to 41.4 wt.%.

The Pontryagin class for pre-Courant algebroids

NASA Astrophysics Data System (ADS)

Liu, Zhangju; Sheng, Yunhe; Xu, Xiaomeng

2016-06-01

In this paper, we show that the Jacobiator J of a pre-Courant algebroid is closed naturally. The corresponding equivalence class [J♭ ] is defined as the Pontryagin class, which is the obstruction of a pre-Courant algebroid to be deformed into a Courant algebroid. We construct a Leibniz 2-algebra and a Lie 2-algebra associated to a pre-Courant algebroid and prove that these algebraic structures are isomorphic under deformations. Finally, we introduce the twisted action of a Lie algebra on a manifold to give more examples of pre-Courant algebroids, which include the Cartan geometry.

On representations of U{sub q}osp(1{vert_bar}2) when q is a root of unity

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

Chung, W.; Suzuki, T.

1997-06-01

The infinite dimensional highest weight representations of U{sub q}osp(1{vert_bar}2) for the deformation parameter q being a root of unity are investigated. As in the cases of q-deformed nongraded Lie algebras, we find that every irreducible representation is isomorphic to the tensor product of a highest weight representation of sl{sub 2}(R) and a finite dimensional one of U{sub q}osp(1{vert_bar}2). The structure is investigated in detail. {copyright} {ital 1997 American Institute of Physics.}

Demonstration of the Jaynes-Cummings ladder with Rydberg-dressed atoms

DOE PAGES

Lee, Jongmin; Martin, Michael J.; Jau, Yuan-Yu; ...

2017-04-06

Here, we observe the nonlinearity of the Jaynes-Cummings (JC) ladder in the Autler-Townes spectroscopy of the hyperfine ground states for a Rydberg-dressed two-atom system. The role of the two-level system in the JC model is played by the presence or absence of a collective Rydberg excitation, and the bosonic mode manifests as the number n of single-atom spin flips, symmetrically distributed between the atoms. We also measure the normal-mode splitting and √ n nonlinearity as a function of detuning and Rabi frequency, thereby experimentally establishing the isomorphism with the JC model.

Soft Congruence Relations over Rings

PubMed Central

Xin, Xiaolong; Li, Wenting

2014-01-01

Molodtsov introduced the concept of soft sets, which can be seen as a new mathematical tool for dealing with uncertainty. In this paper, we initiate the study of soft congruence relations by using the soft set theory. The notions of soft quotient rings, generalized soft ideals and generalized soft quotient rings, are introduced, and several related properties are investigated. Also, we obtain a one-to-one correspondence between soft congruence relations and idealistic soft rings and a one-to-one correspondence between soft congruence relations and soft ideals. In particular, the first, second, and third soft isomorphism theorems are established, respectively. PMID:24949493

Lanthanide contraction effect on crystal structures of lanthanide coordination polymers with cyclohexanocucurbit[6]uril ligand

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

Zheng, Li-Mei; Liu, Jing-Xin, E-mail: jxliu411@ahut.edu.cn

A series of compounds based on the macrocyclic ligand cyclohexanocucurbit[6]uril (Cy6Q[6]) with formulas (Ln(H{sub 2}O){sub 6}Cy6Q[6])·2(CdCl{sub 4})·H{sub 3}O·xH{sub 2}O [isomorphous with Ln=La (1), Ce (2), Pr (3) and Nd (4), x=11 (1), 11 (2), 10 (3) and 11 (4)], (Sm(H{sub 2}O){sub 5}Cy6Q[6])·2(CdCl{sub 4})·H{sub 3}O·10H{sub 2}O (5) and (Ln(H{sub 2}O){sub 5}(NO{sub 3})@Cy6Q[6])·2(CdCl{sub 4})·2H{sub 3}O·xH{sub 2}O [isomorphous with Ln=Gd (6), Tb (7) and Dy (8), x=8 (6), 6 (7) and 6 (8)], have been successfully synthesized by the self-assembly of Cy6Q[6] with the corresponding lanthanide nitrate under hydrochloric acid aqueous solution in the presence of CdCl{sub 2}. Single-crystal X-ray diffraction analyses revealedmore » that compounds 1–8 all crystallize in monoclinic space group P2{sub 1}/c, and display 1D coordination polymer structures. The lanthanide contraction effect on the structures of 1–8 has also been investigated and discussed in detail. In contrast, the reaction of Cy6Q[6] with the Ho(NO){sub 3}, Tm(NO){sub 3}, Yb(NO){sub 3} under the same conditions resulted in the compounds 9–11 with formulas Cy6Q[6]·2(CdCl{sub 4})·2H{sub 3}O·xH{sub 2}O [isomorphous with x=10 (9), 10 (10), and 9 (11)], in which no lanthanide cations are observed. The structural difference of these compounds indicates that the Cy6Q[6] may be used in the separation of lanthanide cations. - Graphical abstract: The reaction of cyclohexanocucurbit[6]uril with lanthanide ions (La{sup 3+}, Ce{sup 3+}, Pr{sup 3+}, Nd{sup 3+}, Sm{sup 3+}, Gd{sup 3+}, Tb{sup 3+}, Dy{sup 3+}, Ho{sup 3+}, Tm{sup 3+} and Yb{sup 3+}) under hydrochloric acid in the presence of CdCl{sub 2} resulted in eleven compounds, which demonstrate interesting lanthanide contraction effect and provide a means of separating lanthanide ions. - Highlights: • Eleven compounds of the Ln{sup 3+} with the Cy6Q[6] were synthesized and described. • Compounds 1-8 demonstrate interesting lanthanide contraction effect. • In solid-state structures of compounds 9-11, no lanthanide ions were observed. • This study provides a means of separating lanthanides cations.« less

The application of GBS markers for extending the dense genetic map of rye (Secale cereale L.) and the localization of the Rfc1 gene restoring male fertility in plants with the C source of sterility-inducing cytoplasm.

PubMed

Milczarski, Paweł; Hanek, Monika; Tyrka, Mirosław; Stojałowski, Stefan

2016-11-01

Genotyping by sequencing (GBS) is an efficient method of genotyping in numerous plant species. One of the crucial steps toward the application of GBS markers in crop improvement is anchoring them on particular chromosomes. In rye (Secale cereale L.), chromosomal localization of GBS markers has not yet been reported. In this paper, the application of GBS markers generated by the DArTseq platform for extending the high-density map of rye is presented. Additionally, their application is used for the localization of the Rfc1 gene that restores male fertility in plants with the C source of sterility-inducing cytoplasm. The total number of markers anchored on the current version of the map is 19,081, of which 18,132 were obtained from the DArTseq platform. Numerous markers co-segregated within the studied mapping population, so, finally, only 3397 unique positions were located on the map of all seven rye chromosomes. The total length of the map is 1593 cM and the average distance between markers is 0.47 cM. In spite of the resolution of the map being not very high, it should be a useful tool for further studies of the Secale cereale genome because of the presence on this map of numerous GBS markers anchored for the first time on rye chromosomes. The Rfc1 gene was located on high-density maps of the long arm of the 4R chromosome obtained for two mapping populations. Genetic maps were composed of DArT, DArTseq, and PCR-based markers. Consistent mapping results were obtained and DArTs tightly linked to the Rfc1 gene were successfully applied for the development of six new PCR-based markers useful in marker-assisted selection.

CR108, a novel vitamin K3 derivative induces apoptosis and breast tumor inhibition by reactive oxygen species and mitochondrial dysfunction

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

Yang, Chun-Ru; Liao, Wei-Siang; Wu, Ya-Hui

Vitamin K3 derivatives have been shown to exert anticancer activities. Here we show a novel vitamin K3 derivative (S)-2-(2-hydroxy-3-methylbutylthio)naphthalene-1,4-dione, which is named as CR108 that induces apoptosis and tumor inhibition through reactive oxygen species (ROS) and mitochondrial dysfunction in human breast cancer. CR108 is more effective on the breast cancer cell death than other vitamin K3 derivatives. Moreover, CR108 induced apoptosis in both the non-HER-2-overexpressed MCF-7 and HER-2-overexpressed BT-474 breast cancer cells. CR108 caused the loss of mitochondrial membrane potential, cytochrome c released from mitochondria to cytosol, and cleaved PARP proteins for apoptosis induction. CR108 markedly increased ROS levels inmore » breast cancer cells. N-acetylcysteine (NAC), a general ROS scavenger, completely blocked the CR108-induced ROS levels, mitochondrial dysfunction and apoptosis. Interestingly, CR108 increased the phosphorylation of p38 MAP kinase but conversely inhibited the survivin protein expression. NAC treatment prevented the activation of p38 MAP kinase and rescued the survivin protein levels. SB202190, a specific p38 MAP kinase inhibitor, recovered the survivin protein levels and attenuated the cytotoxicity of CR108-treated cells. Furthermore, CR108 inhibited the xenografted human breast tumor growth in nude mice. Together, we demonstrate that CR108 is a novel vitamin K3 derivative that induces apoptosis and tumor inhibition by ROS production and mitochondrial dysfunction and associates with the phosphorylation of p38 MAP kinase and the inhibition of survivin in the human breast cancer. - Highlights: • CR108 is more effective on the cell death than other vitamin K3 derivatives. • CR108 induces apoptosis and tumor inhibition by ROS and mitochondrial dysfunction. • CR108 induces apoptosis by p38 kinase activation and survivin inhibition. • CR108 is a potent vitamin K3 analog that can develop for breast cancer therapy.« less

A superoxide anion-scavenger, 1,3-selenazolidin-4-one suppresses serum deprivation-induced apoptosis in PC12 cells by activating MAP kinase

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

Nishina, Atsuyoshi, E-mail: nishina@yone.ac.jp; Kimura, Hirokazu; Kozawa, Kunihisa

Synthetic organic selenium compounds, such as ebselen, may show glutathione peroxidase-like antioxidant activity and have a neurotrophic effect. We synthesized 1,3-selenazolidin-4-ones, new types of synthetic organic selenium compounds (five-member ring compounds), to study their possible applications as antioxidants or neurotrophic-like molecules. Their superoxide radical scavenging effects were assessed using the quantitative, highly sensitive method of real-time kinetic chemiluminescence. At 166 {mu}M, the O{sub 2}{sup -} scavenging activity of 1,3-selenazolidin-4-ones ranged from 0 to 66.2%. 2-[3-(4-Methoxyphenyl)-4-oxo-1,3-selenazolidin-2-ylidene]malononitrile (compound b) showed the strongest superoxide anion-scavenging activity among the 6 kinds of 2-methylene-1,3-selenazolidin-4-ones examined. Compound b had a 50% inhibitory concentration (IC{sub 50}) atmore » 92.4 {mu}M and acted as an effective and potentially useful O{sub 2}{sup -} scavenger in vitro. The effect of compound b on rat pheochromocytome cell line PC12 cells was compared with that of ebselen or nerve growth factor (NGF) by use of the MTT [3-(4, 5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide] assay. When ebselen was added at 100 {mu}M or more, toxicity toward PC12 cells was evident. On the contrary, compound b suppressed serum deprivation-induced apoptosis in PC12 cells more effectively at a concentration of 100 {mu}M. The activity of compound b to phosphorylate mitogen-activated protein kinase/extracellular signal-regulated protein kinase (ERK) 1/2 (MAP kinase) in PC12 cells was higher than that of ebselen, and the former at 100 {mu}M induced the phosphorylation of MAP kinase to a degree similar to that induced by NGF. From these results, we conclude that this superoxide anion-scavenger, compound b, suppressed serum deprivation-induced apoptosis by promoting the phosphorylation of MAP kinase. -- Highlights: Black-Right-Pointing-Pointer We newly synthesized 1,3-selenazolidin-4-ones to study their possible applications. Black-Right-Pointing-Pointer Among new compounds, compound b showed the strongest SOSA. Black-Right-Pointing-Pointer Compound b suppressed serum deprivation-induced apoptosis in PC12 cells. Black-Right-Pointing-Pointer Compound b suppressed apoptosis by promoting the activation of MAP kinase.« less

Mouse strains to study cold-inducible beige progenitors and beige adipocyte formation and function

PubMed Central

Berry, Daniel C.; Jiang, Yuwei; Graff, Jonathan M.

2016-01-01

Cold temperatures induce formation of beige adipocytes, which convert glucose and fatty acids to heat, and may increase energy expenditure, reduce adiposity and lower blood glucose. This therapeutic potential is unrealized, hindered by a dearth of genetic tools to fate map, track and manipulate beige progenitors and ‘beiging'. Here we examined 12 Cre/inducible Cre mouse strains that mark adipocyte, muscle and mural lineages, three proposed beige origins. Among these mouse strains, only those that marked perivascular mural cells tracked the cold-induced beige lineage. Two SMA-based strains, SMA-CreERT2 and SMA-rtTA, fate mapped into the majority of cold-induced beige adipocytes and SMA-marked progenitors appeared essential for beiging. Disruption of the potential of the SMA-tracked progenitors to form beige adipocytes was accompanied by an inability to maintain body temperature and by hyperglycaemia. Thus, SMA-engineered mice may be useful to track and manipulate beige progenitors, beige adipocyte formation and function. PMID:26729601

Bovine response to lipoarabinomannan vaccination and challenge with Mycobacterium paratuberculosis.

PubMed

Jolly, Ana; Morsella, Claudia; Bass, Laura; Fiorentino, María Andrea; Paolicchi, Fernando Alberto; Mundo, Silvia Leonor

2013-01-01

This study aimed to evaluate the immune response in bovines following immunization with a mycobaterial Lipoarabinomannan extract (LAMe) and the effect of Map challenge. LAMe vaccine induced specific antibody levels that diminished after the challenge and affected Map excretion at least for 100 days thereafter.

Down-Regulation by Resveratrol of Basic Fibroblast Growth Factor-Stimulated Osteoprotegerin Synthesis through Suppression of Akt in Osteoblasts

PubMed Central

Kuroyanagi, Gen; Otsuka, Takanobu; Yamamoto, Naohiro; Matsushima-Nishiwaki, Rie; Nakakami, Akira; Mizutani, Jun; Kozawa, Osamu; Tokuda, Haruhiko

2014-01-01

It is firmly established that resveratrol, a natural food compound abundantly found in grape skins and red wine, has beneficial properties for human health. In the present study, we investigated the effect of basic fibroblast growth factor (FGF-2) on osteoprotegerin (OPG) synthesis in osteoblast-like MC3T3-E1 cells and whether resveratrol affects the OPG synthesis. FGF-2 stimulated both the OPG release and the expression of OPG mRNA. Resveratrol significantly suppressed the FGF-2-stimulated OPG release and the mRNA levels of OPG. SRT1720, an activator of SIRT1, reduced the FGF-2-induced OPG release and the OPG mRNA expression. PD98059, an inhibitor of upstream kinase activating p44/p42 mitogen-activated protein (MAP) kinase, had little effect on the FGF-2-stimulated OPG release. On the other hand, SB203580, an inhibitor of p38 MAP kinase, SP600125, an inhibitor of stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), and Akt inhibitor suppressed the OPG release induced by FGF-2. Resveratrol failed to affect the FGF-2-induced phosphorylation of p44/p42 MAP kinase, p38 MAP kinase or SAPK/JNK. The phosphorylation of Akt induced by FGF-2 was significantly suppressed by resveratrol or SRT1720. These findings strongly suggest that resveratrol down-regulates FGF-2-stimulated OPG synthesis through the suppression of the Akt pathway in osteoblasts and that the inhibitory effect of resveratrol is mediated at least in part by SIRT1 activation. PMID:25290095

Interaction between graviception and carotid baroreflex function in humans during parabolic flight-induced microgravity.

PubMed

Ogoh, Shigehiko; Marais, Michaël; Lericollais, Romain; Denise, Pierre; Raven, Peter B; Normand, Hervé

2018-05-10

The aim of the present study was to assess carotid baroreflex (CBR) during acute changes in otolithic activity in humans. To address this question, we designed a set of experiments to identify the modulatory effects of microgravity on CBR function at a tilt angle of -2{degree sign}, which was identified to minimize changes in central blood volume during parabolic flight. During parabolic flight at 0g and 1g, CBR function curves were modelled from the heart rate (HR) and mean arterial pressure (MAP) responses to rapid pulse trains of neck pressure (NP) and neck suction (NS) ranging from +40 to -80 Torr; CBR control of HR (carotid-HR) and MAP (carotid-MAP) baroreflex function curves, respectively. The maximal gain (G max ) of both carotid-HR and carotid-MAP baroreflex function curves were augmented during microgravity compared to 1g (carotid-HR, -0.53 to -0.80 beats/min/mmHg, P<0.05; carotid-MAP, -0.24 to -0.30 mmHg/mmHg, P<0.05). These findings suggest that parabolic flight-induced acute change of otolithic activity may modify CBR function and identifies that the vestibular system contributes to blood pressure regulation under fluctuations in gravitational forces.

Striatal and extrastriatal dopamine release in the common marmoset brain measured by positron emission tomography and [(18)F]fallypride.

PubMed

Ota, Miho; Ogawa, Shintaro; Kato, Koichi; Masuda, Chiaki; Kunugi, Hiroshi

2015-12-01

Previous studies have demonstrated that patients with schizophrenia show greater sensitivity to psychostimulants than healthy subjects. Sensitization to psychostimulants and resultant alteration of dopaminergic neurotransmission in rodents has been suggested as a useful model of schizophrenia. This study sought to examine the use of methylphenidate as a psychostimulant to induce dopamine release and that of [(18)F]fallypride as a radioligand to quantify the release in a primate model of schizophrenia. Four common marmosets were scanned by positron emission tomography twice, before and after methylphenidate challenge, to evaluate dopamine release. Four other marmosets were sensitized by repeated methamphetamine (MAP) administration. Then, they were scanned twice, before and after methylphenidate challenge, to evaluate whether MAP-sensitization induced greater sensitivity to methylphenidate. We revealed a main effect of the methylphenidate challenge but not the MAP pretreatment on the striatal binding potential. These results suggest that methylphenidate-induced striatal dopamine release in the common marmoset could be evaluated by [(18)F]fallypride. Copyright © 2015 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Resveratrol Inhibits the Epidermal Growth Factor-Induced Migration of Osteoblasts: the Suppression of SAPK/JNK and Akt.

PubMed

Kawabata, Tetsu; Tokuda, Haruhiko; Fujita, Kazuhiko; Kainuma, Shingo; Sakai, Go; Matsushima-Nishiwaki, Rie; Kozawa, Osamu; Otsuka, Takanobu

2017-01-01

Resveratrol is a polyphenol enriched in the skins of grapes and berries, that shows various beneficial effects for human health. In the present study, we investigated the mechanism behind the epidermal growth factor (EGF)-induced migration of osteoblast-like MC3T3-E1 cells, and the effect of resveratrol on this cell migration. The cell migration was examined using Boyden chamber, and phosphorylation of each kinase was analyzed by Western blotting. The EGF-induced migration was suppressed by PD98059, an inhibitor of MEK1/2, as well as SB203580, an inhibitor of p38 MAP kinase, SP600125, an inhibitor of SAPK/JNK, and deguelin, an inhibitor of Akt. In contrast, rapamycin, an inhibitor of upstream kinase of p70 S6 kinase, and fasudil, an inhibitor of Rho-kinase, hardly affected the migration. Resveratrol significantly reduced the EGF-induced migration in a dose-dependent manner. SRT1720, an SIRT1 activator, suppressed the migration by EGF. In addition, resveratrol markedly attenuated the EGF-induced phosphorylation of SAPK/JNK and Akt without affecting the phosphorylation of p44/p42 MAP kinase or p38 MAP kinase. The phosphorylation of SAPK/JNK and Akt induced by EGF was down-regulated by SRT1720. Our results strongly suggest that resveratrol reduces the EGF-stimulated migration of osteoblasts via suppression of SAPK and Akt, and that the inhibitory effect of resveratrol is mediated in part via SIRT1. © 2017 The Author(s). Published by S. Karger AG, Basel.

Reasons for recurrent ventricular tachycardia after catheter ablation of post-infarction ventricular tachycardia.

PubMed

Yokokawa, Miki; Desjardins, Benoit; Crawford, Thomas; Good, Eric; Morady, Fred; Bogun, Frank

2013-01-08

The purpose of this study was to assess the determinants of ventricular tachycardia (VT) recurrence in patients who underwent VT ablation for post-infarction VT. The factors that predict recurrence of VT after catheter ablation in patients with prior infarctions are not well described. Catheter ablation was performed in 98 consecutive patients (88 males [90%]; mean age 67 ± 10 years; ejection fraction 27 ± 13%) with post-infarction VT. Electrograms from the implantable cardioverter-defibrillator were analyzed, and VTs were classified as clinical, nonclinical, or new clinical. A total of 725 VTs were induced during the ablation procedure. All VTs were targeted. In 76 patients, 105 clinical VTs were inducible. Critical sites were identified with entrainment mapping and pace-mapping (≥10 of 12 matching leads) for 75 of 105 clinical VTs (71%) and for 278 of 620 nonclinical VTs (45%). Post-ablation, the clinical VT was not inducible in any patient, and all VTs were rendered noninducible in 63% of the patients. Over a mean follow-up period of 35 ± 23 months, 65 of 98 patients (66%) had no recurrent VTs and 33 (34%) had VT recurrence. A new VT occurred in 26 of 33 patients (79%), and a prior clinical VT recurred in 7 patients (21%). Patients with recurrent VT had a larger scar area as assessed by electroanatomic mapping compared with patients without recurrent VTs (93 ± 40 cm(2) vs. 69 ± 30 cm(2); p = 0.002). In patients with repeat procedures, the majority of inducible VTs for which a critical area could be identified were at a distance of 6 ± 3 mm to the prior ablation lesions. Patients with recurrent VTs have a larger scar as assessed by electroanatomic mapping. Most recurrent VTs were new, and the majority of these VTs were mapped to the vicinity of prior ablation lesions in patients with repeat procedures. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Bovine response to lipoarabinomannan vaccination and challenge with Mycobacterium paratuberculosis

PubMed Central

Jolly, Ana; Morsella, Claudia; Bass, Laura; Fiorentino, María Andrea; Paolicchi, Fernando Alberto; Mundo, Silvia Leonor

2013-01-01

This study aimed to evaluate the immune response in bovines following immunization with a mycobaterial Lipoarabinomannan extract (LAMe) and the effect of Map challenge. LAMe vaccine induced specific antibody levels that diminished after the challenge and affected Map excretion at least for 100 days thereafter. PMID:24294248

Developing stressor-watershed function relationships to refine the national maps of watershed integrity

EPA Science Inventory

Abstract ESA 2017Developing stressor-watershed function relationships to refine the national maps of watershed integrityJohnson, Z.C., S.G. Leibowitz, and R.A. Hill. To be submitted to the Ecological Society of America Annual Meeting, Portland, OR. August 2017.Human-induced ecolo...

44 CFR 65.11 - Evaluation of sand dunes in mapping coastal flood hazard areas.

Code of Federal Regulations, 2010 CFR

2010-10-01

... storm-induced dune erosion potential in its determination of coastal flood hazards and risk mapping... base flood storm surges and associated wave action where the cross-sectional area of the primary... storm surges and associated wave action. [53 FR 16279, May 6, 1988] ...