Journal articles on the topic 'Isolanti topologici'

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1

Aguiar, Giancarlo De França, Bárbara De Cassia Xavier Cassins Aguiar, Humberto De AlencarPizza Silva, Volmir Eugênio Wilhelm, and Helena Maria Wilhelm. "Modelagem de novos nós lógicos baseados na IEC 61850 para aplicação em sistemas de gestão de transformadores de potência." Revista Tecnologia e Sociedade 17, no. 46 (January 1, 2021): 229. http://dx.doi.org/10.3895/rts.v17n46.11824.

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Este trabalho apresenta o modelamento de dois novos Nós Lógicos para a norma IEC 61850. Estes modelos foram implementados no monitoramento de dois transformadores de transmissão e distribuição para a criação de um sistema de gestão destes ativos, cuja topologia foi elaborada com base na norma IEC 61850. Este trabalho contribui para a revisão do capítulo da norma que versa sobre monitoramento e supervisão de transformadores (IEC 61850-7-4) e inaugura modelos de Diagnostico e Expectativa de sua Vida Útil. A implementação foi realizada na área piloto do projeto (subestação Pilarzinho), de forma experimental e, avaliados e validados em campo, através da utilização de uma técnica não invasiva de avaliação da degradação do sistema de isolamento dos transformadores, a chamada Espectroscopia Dielétrica por Corrente de Polarização e Despolarização (PDC) e a Medida de Condutividade do Óleo Isolante (LCM). Foi implementado também o processo de secagem da parte ativa baseado em filtros moleculares e que consiste na remoção seletiva das moléculas de água do óleo isolante provocando um desequilíbrio entre a umidade dos materiais isolantes.
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Dube, Matthew P. "Deriving topological relations from topologically augmented direction relation matrices." Journal of Spatial Information Science, no. 23 (December 24, 2021): 1–23. http://dx.doi.org/10.5311/josis.2021.23.155.

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Topological relations and direction relations represent two pieces of the qualitative spatial reasoning triumvirate. Researchers have previously attempted to use the direction relation matrix to derive a topological relation, finding that no single direction relation matrix can isolate a particular topological relation. In this paper, the technique of topological augmentation is applied to the same problem, identifying a unique topological relation in 28.6% of all topologically augmented direction relation matrices, and furthermore achieving a reduction in a further 40.4% of topologically augmented direction relation matrices when compared to their vanilla direction relation matrix counterpart.
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3

Yuvaraj, Monisha, Asim K. Dey, Vyacheslav Lyubchich, Yulia R. Gel, and H. Vincent Poor. "Topological clustering of multilayer networks." Proceedings of the National Academy of Sciences 118, no. 21 (May 18, 2021): e2019994118. http://dx.doi.org/10.1073/pnas.2019994118.

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Multilayer networks continue to gain significant attention in many areas of study, particularly due to their high utility in modeling interdependent systems such as critical infrastructures, human brain connectome, and socioenvironmental ecosystems. However, clustering of multilayer networks, especially using the information on higher-order interactions of the system entities, still remains in its infancy. In turn, higher-order connectivity is often the key in such multilayer network applications as developing optimal partitioning of critical infrastructures in order to isolate unhealthy system components under cyber-physical threats and simultaneous identification of multiple brain regions affected by trauma or mental illness. In this paper, we introduce the concepts of topological data analysis to studies of complex multilayer networks and propose a topological approach for network clustering. The key rationale is to group nodes based not on pairwise connectivity patterns or relationships between observations recorded at two individual nodes but based on how similar in shape their local neighborhoods are at various resolution scales. Since shapes of local node neighborhoods are quantified using a topological summary in terms of persistence diagrams, we refer to the approach as clustering using persistence diagrams (CPD). CPD systematically accounts for the important heterogeneous higher-order properties of node interactions within and in-between network layers and integrates information from the node neighbors. We illustrate the utility of CPD by applying it to an emerging problem of societal importance: vulnerability zoning of residential properties to weather- and climate-induced risks in the context of house insurance claim dynamics.
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Dutta, Bivas, Vladimir Umansky, Mitali Banerjee, and Moty Heiblum. "Isolated ballistic non-abelian interface channel." Science 377, no. 6611 (September 9, 2022): 1198–201. http://dx.doi.org/10.1126/science.abm6571.

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The topological order of a quantum Hall state is mirrored by the gapless edge modes owing to bulk-edge correspondence. The state at the filling of ν = 5/2, predicted to host non-abelian anyons, supports a variety of edge modes (integer, fractional, neutral). To ensure thermal equilibration between the edge modes and thus accurately determine the state’s nature, it is advantageous to isolate the fractional channel (1/2 and neutral modes). In this study, we gapped out the integer modes by interfacing the ν = 5/2 state with integer states ν = 2 and ν = 3 and measured the thermal conductance of the isolated-interface channel. Our measured half-quantized thermal conductance confirms the non-abelian nature of the ν = 5/2 state and its particle-hole Pfaffian topological order. Such an isolated channel may be more amenable to braiding experiments.
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Kauth, Christian, Marc Pastre, Jean-Michel Sallese, and Maher Kayal. "System-Level Design Considerations for Carbon Nanotube Electromechanical Resonators." Journal of Sensors 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/384643.

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Despite an evermore complete plethora of complex domain-specific semiempirical models, no succinct recipe for large-scale carbon nanotube electromechanical systems design has been formulated. To combine the benefits of these highly sensitive miniaturized mechanical sensors with the vast functionalities available in electronics, we identify a reduced key parameter set of carbon nanotube properties, nanoelectromechanical system design, and operation that steers the sensor’s performance towards system applications, based on open- and closed-loop topologies. Suspended single-walled carbon nanotubes are reviewed in terms of their electromechanical properties with the objective of evaluating orders of magnitude of the electrical actuation and detection mechanisms. Open-loop time-averaging and 1ωor 2ωmixing methods are completed by a new 4ωactuation and detection technique. A discussion on their extension to closed-loop topologies and system applications concludes the analysis, covering signal-to-noise ratio, and the capability to spectrally isolate the motional information from parasitical feedthrough by contemporary electronic read-out techniques.
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6

Cain, Jeffrey D., Amin Azizi, Matthias Conrad, Sinéad M. Griffin, and Alex Zettl. "Layer-dependent topological phase in a two-dimensional quasicrystal and approximant." Proceedings of the National Academy of Sciences 117, no. 42 (October 5, 2020): 26135–40. http://dx.doi.org/10.1073/pnas.2015164117.

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The electronic and topological properties of materials are derived from the interplay between crystalline symmetry and dimensionality. Simultaneously introducing “forbidden” symmetries via quasiperiodic ordering with low dimensionality into a material system promises the emergence of new physical phenomena. Here, we isolate a two-dimensional (2D) chalcogenide quasicrystal and approximant, and investigate their electronic and topological properties. The 2D layers of the materials with a composition close to Ta1.6Te, derived from a layered transition metal dichalcogenide, are isolated with standard exfoliation techniques, and investigated with electron diffraction and atomic resolution scanning transmission electron microscopy. Density functional theory calculations and symmetry analysis of the large unit cell crystalline approximant of the quasicrystal, Ta21Te13, reveal the presence of symmetry-protected nodal crossings in the quasicrystalline and approximant phases, whose presence is tunable by layer number. Our study provides a platform for the exploration of physics in quasicrystalline, low-dimensional materials and the interconnected nature of topology, dimensionality, and symmetry in electronic systems.
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7

BERGER, ULRICH, JENS BLANCK, and PETTER KRISTIAN KØBER. "Domain representations of spaces of compact subsets." Mathematical Structures in Computer Science 20, no. 2 (March 25, 2010): 107–26. http://dx.doi.org/10.1017/s096012950999034x.

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We present a method for constructing from a given domain representation of a space X with underlying domain D, a domain representation of a subspace of compact subsets of X where the underlying domain is the Plotkin powerdomain of D. We show that this operation is functorial over a category of domain representations with a natural choice of morphisms. We study the topological properties of the space of representable compact sets and isolate conditions under which all compact subsets of X are representable. Special attention is paid to admissible representations and representations of metric spaces.
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8

Chaput, Dominique L., David Bass, Md Mehedi Alam, Neaz Al Hasan, Grant D. Stentiford, Ronny van Aerle, Karen Moore, John P. Bignell, Mohammad Mahfujul Haque, and Charles R. Tyler. "The Segment Matters: Probable Reassortment of Tilapia Lake Virus (TiLV) Complicates Phylogenetic Analysis and Inference of Geographical Origin of New Isolate from Bangladesh." Viruses 12, no. 3 (February 27, 2020): 258. http://dx.doi.org/10.3390/v12030258.

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Tilapia lake virus (TiLV), a negative sense RNA virus with a 10 segment genome, is an emerging threat to tilapia aquaculture worldwide, with outbreaks causing over 90% mortality reported on several continents since 2014. Following a severe tilapia mortality event in July 2017, we confirmed the presence of TiLV in Bangladesh and obtained the near-complete genome of this isolate, BD-2017. Phylogenetic analysis of the concatenated 10 segment coding regions placed BD-2017 in a clade with the two isolates from Thailand, separate from the Israeli and South American isolates. However, phylogenetic analysis of individual segments gave conflicting results, sometimes clustering BD-2017 with one of the Israeli isolates, and splitting pairs of isolates from the same region. By comparing patterns of topological difference among segments of quartets of isolates, we showed that TiLV likely has a history of reassortment. Segments 5 and 6, in particular, appear to have undergone a relatively recent reassortment event involving Ecuador isolate EC-2012 and Israel isolate Til-4-2011. The phylogeny of TiLV isolates therefore depends on the segment sequenced. Our findings illustrate the need to exercise caution when using phylogenetic analysis to infer geographic origin and track the movement of TiLV, and we recommend using whole genomes wherever possible.
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9

Colombari, Boris. "Welded extensions and ribbon restrictions of diagrammatical moves." Journal of Knot Theory and Its Ramifications 30, no. 02 (February 2021): 2150008. http://dx.doi.org/10.1142/s0218216521500085.

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In this paper, we consider local moves on classical and welded diagrams of string links, and the notion of welded extension of a classical move. Such extensions being non-unique in general, the idea is to find a topological criterion which could isolate one extension from the others. To that end, we turn to the relation between welded string links and knotted surfaces in [Formula: see text], and the ribbon subclass of these surfaces. This provides a topological interpretation of classical local moves as surgeries on surfaces, and of virtual local moves as surgeries on ribbon surfaces. Comparing these surgeries leads to the notion of ribbon residue of a classical local move, and we show that up to some broad conditions there can be at most one welded extension which is a ribbon residue. We provide three examples of ribbon residues, for the self-crossing change, the Delta and the band-pass moves. However, for the latter, we note that the given residue is actually not an extension of the band-pass move, showing that a classical move may have a ribbon residue and a welded extension, but no ribbon residue which is an extension.
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10

Yang, Jianting, Kongyang Zhao, Muzi Li, Zhu Xu, and Zhilin Li. "Identifying Complex Junctions in a Road Network." ISPRS International Journal of Geo-Information 10, no. 1 (December 24, 2020): 4. http://dx.doi.org/10.3390/ijgi10010004.

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Automated generalization of road network data is of great concern to the map generalization community because of the importance of road data and the difficulty involved. Complex junctions are where roads meet and join in a complicated way and identifying them is a key issue in road network generalization. In addition to their structural complexity, complex junctions don’t have regular geometric boundary and their representation in spatial data is scale-dependent. All these together make them hard to identify. Existing methods use geometric and topological statistics to characterize and identify them, and are thus error-prone, scale-dependent and lack generality. More significantly, they cannot ensure the integrity of complex junctions. This study overcomes the obstacles by clarifying the topological boundary of a complex junction, which provides the basis for straightforward identification of them. Test results show the proposed method can find and isolate complex junctions in a road network with their integrity and is able to handle different road representations. The integral identification achieved can help to guarantee connectivity among roads when simplifying complex junctions, and greatly facilitate the geometric and semantic simplification of them.
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11

Gillespie, P. G., and A. J. Hudspeth. "High-purity isolation of bullfrog hair bundles and subcellular and topological localization of constituent proteins." Journal of Cell Biology 112, no. 4 (February 15, 1991): 625–40. http://dx.doi.org/10.1083/jcb.112.4.625.

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The small number of hair cells in auditory and vestibular organs severely impedes the biochemical characterization of the proteins involved in mechano-electrical transduction. By developing an efficient and clean "twist-off" method of hair bundle isolation, and by devising a sensitive, nonradioactive method to detect minute quantities of protein, we have partially overcome this limitation and have extensively classified the proteins of the bundles. To isolate hair bundles, we glue the saccular macula of the bullfrog to a glass coverslip, expose the tissue to a molten agarose solution, and allow the agarose to solidify to a firm gel. By rotating the gel disk with respect to the fixed macula, we isolate the hair bundles by shearing them at their mechanically weak bases. The plasma membranes of at least 80% of the stereocilia reseal. To visualize the proteins of the hair bundle, we covalently label them with biotin, separate them by SDS-PAGE, and transfer them to a charged nylon membrane. We can detect less than 500 fg of protein by probing the membrane with streptavidin-alkaline phosphatase and detecting the chemiluminescent product from the hydrolysis of the substrate 3-(4-methoxyspiro-(1,2-dioxetane-3,2'-tricyclo-[3.3.1. 1(3.7)]decan)-4-yl) phenyl phosphate (AMPPD). These techniques reveal a distinct constellation of proteins in and associated with hair bundles. Several proteins, such as calmodulin, calbindin, actin, tubulin, and fimbrin, have previously been described. A second class of proteins in the preparation appears to be derived from extracellular sources. Finally, several heretofore undescribed bundle proteins are identified and characterized by their membrane topology, subcellular localization, and glycosidase and protease sensitivities.
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12

KUDELSKI, DIMITRI, SOPHIE VISEUR, GIOVANNI SCROFANI, and JEAN-LUC MARI. "FEATURE LINE EXTRACTION ON MESHES THROUGH VERTEX MARKING AND 2D TOPOLOGICAL OPERATORS." International Journal of Image and Graphics 11, no. 04 (October 2011): 531–48. http://dx.doi.org/10.1142/s0219467811004226.

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Classical approaches of feature line detection rely on curvature derivatives. They generally suffer from a common problem: the connectivity is hard to obtain and it is impossible to generate intersections between feature lines. This article presents a method to extract feature lines on 3D meshes. In order to sort out the recurrent issues of traditional approaches, we propose a novel algorithm based on two ideas. First, all the mesh vertices are marked according to the curvature values: a binary map with candidate regions is then constructed. The second idea is to isolate each candidate region and transform it into a line. To achieve this, we parameterize the region into its 2D regular representation. We then perform a skeletonization to obtain lines with high connectivity. By applying the inverse parameterization, the feature lines are mapped back onto the 3D mesh. In the end, we extract perceptual salient parts and above all connected feature lines. In order to evaluate and validate our algorithm, we compare our method to classical ones and apply our technique to a geological context.
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13

Thibessard, Annabelle, Annabelle Fernandez, Brigitte Gintz, Nathalie Leblond-Bourget, and Bernard Decaris. "Effects of rodA and pbp2b Disruption on Cell Morphology and Oxidative Stress Response of Streptococcus thermophilus CNRZ368." Journal of Bacteriology 184, no. 10 (May 15, 2002): 2821–26. http://dx.doi.org/10.1128/jb.184.10.2821-2826.2002.

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ABSTRACT Insertional mutagenesis was used to isolate clones from Streptococcus thermophilus CNRZ368 that were modified in their abilities to tolerate oxidative stress. During this process, two menadione-sensitive clones (6G4 and 18C3) were found to display abnormal cell morphologies and distorted chain topologies and were further studied. Molecular characterization of both 6G4 and 18C3 mutants indicated that they were disrupted in open reading frames homologous to rodA and pbp2b, respectively. Both genes encoded proteins in Escherichia coli that were described as being implicated in peptidoglycan synthesis during the process of cell elongation and to function in determining the rod shape of the cell. This work reports a possible connection between peptidoglycan biosynthesis and oxidative stress defense in S. thermophilus CNRZ368.
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14

Diakité, A. A., and S. Zlatanova. "EXTRACTION OF THE 3D FREE SPACE FROM BUILDING MODELS FOR INDOOR NAVIGATION." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences IV-2/W1 (October 5, 2016): 241–48. http://dx.doi.org/10.5194/isprs-annals-iv-2-w1-241-2016.

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For several decades, indoor navigation has been exclusively investigated in a 2D perspective, based on floor plans, projection and other 2D representations of buildings. Nevertheless, 3D representations are closer to our reality and offer a more intuitive description of the space configuration. Thanks to recent advances in 3D modelling, 3D navigation is timidly but increasingly gaining in interest through the indoor applications. But, because the structure of indoor environment is often more complex than outdoor, very simplified models are used and obstacles are not considered for indoor navigation leading to limited possibilities in complex buildings. In this paper we consider the entire configuration of the indoor environment in 3D and introduce a method to extract from it the actual navigable space as a network of connected 3D spaces (volumes). We describe how to construct such 3D free spaces from semantically rich and furnished IFC models. The approach combines the geometric, the topological and the semantic information available in a 3D model to isolate the free space from the rest of the components. Furthermore, the extraction of such navigable spaces in building models lacking of semantic information is also considered. A data structure named combinatorial maps is used to support the operations required by the process while preserving the topological and semantic information of the input models.
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Boyle-Vavra, Susan, Jongin Hahm, S. J. Sibener, and Robert S. Daum. "Structural and Topological Differences between a Glycopeptide-Intermediate Clinical Strain and Glycopeptide-Susceptible Strains of Staphylococcus aureus Revealed by Atomic Force Microscopy." Antimicrobial Agents and Chemotherapy 44, no. 12 (December 1, 2000): 3456–60. http://dx.doi.org/10.1128/aac.44.12.3456-3460.2000.

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ABSTRACT Novel cell surface topography was revealed on cocci from a glycopeptide-intermediate Staphylococcus aureus (GISA) clinical strain by using atomic force microscopy. The GISA isolate and its revertant had two parallel circumferential surface rings. One equatorial surface ring was observed in control strains. In vancomycin-susceptible strains, additional rings were formed in the presence of vancomycin. Ring depth measurements also revealed striking differences between the GISA strain and susceptible strains grown with or without vancomycin.
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Cabauatan, Pepito Q., Ulrich Melcher, Koichi Ishikawa, Toshihiro Omura, Hiroyuki Hibino, Hiroki Koganezawa, and Ossmat Azzam. "Sequence changes in six variants of rice tungro bacilliform virus and their phylogenetic relationships." Journal of General Virology 80, no. 8 (August 1, 1999): 2229–37. http://dx.doi.org/10.1099/0022-1317-80-8-2229.

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The DNA of three biological variants, G1, Ic and G2, which originated from the same greenhouse isolate of rice tungro bacilliform virus (RTBV) at the International Rice Research Institute (IRRI), was cloned and sequenced. Comparison of the sequences revealed small differences in genome sizes. The variants were between 95 and 99% identical at the nucleotide and amino acid levels. Alignment of the three genome sequences with those of three published RTBV sequences (Phi-1, Phi-2 and Phi-3) revealed numerous nucleotide substitutions and some insertions and deletions. The published RTBV sequences originated from the same greenhouse isolate at IRRI 20, 11 and 9 years ago. All open reading frames (ORFs) and known functional domains were conserved across the six variants. The cysteine-rich region of ORF3 showed the greatest variation. When the six DNA sequences from IRRI were compared with that of an isolate from Malaysia (Serdang), similar changes were observed in the cysteine-rich region in addition to other nucleotide substitutions and deletions across the genome. The aligned nucleotide sequences of the IRRI variants and Serdang were used to analyse phylogenetic relationships by the bootstrapped parsimony, distance and maximum-likelihood methods. The isolates clustered in three groups: Serdang alone; Ic and G1; and Phi-1, Phi-2, Phi-3 and G2. The distribution of phylogenetically informative residues in the IRRI sequences shared with the Serdang sequence and the differing tree topologies for segments of the genome suggested that recombination, as well as substitutions and insertions or deletions, has played a role in the evolution of RTBV variants. The significance and implications of these evolutionary forces are discussed in comparison with badnaviruses and caulimoviruses.
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Windarko, Novie Ayub, Akhmad Puryanto, Rachma Prilian Eviningsih, Moh Zaenal Efendi, Eka Prasetyono, and Bambang Sumantri. "Prototipe Power Supply Gate driver untuk Multilevel Inverter dengan Menggunakan Flyback Converter Multi Output." Techné : Jurnal Ilmiah Elektroteknika 19, no. 01 (April 14, 2020): 33–42. http://dx.doi.org/10.31358/techne.v19i01.219.

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Dengan perkembangan konverter elektronika daya, kebutuhan untuk memperkecil ukuran dan keandalan semakin meningkat. Dengan meningkatnya frekuensi switching pada konverter, maka dv/dt yang tinggi dapat menyebabkan kesalahan dalam turn-on ataupun turn-off switching devices. Masalah-masalah tersebut dapat diatasi dengan menerapkan tegangan bias negatif untuk melakukan turn-off switching devices. Makalah ini mengusulkan prototipe power supply gate driver yang dikhususkan untuk Multi Level Inverter (MLI). Sebuah prototipe power supply gate driver yang menggunakan satu unit konverter flyback dengan multi output untuk tegangan bias positif dan negatif, serta terisolasi galvanis sebanyak switching devices MLI. Dengan menggunakan topologi dasar flyback maka konverter ini memiliki isolasi galvanis melalui trafo frekuensi tinggi. Dari hasil eksperimen proses switching bisa berubah dari kondisi dari on menuju off dan dari off menuju on bisa berjalan secara sempurna.
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18

Videira, Paula A., Abbner P. Garcia, and Isabel Sá-Correia. "Functional and Topological Analysis of the Burkholderia cenocepacia Priming Glucosyltransferase BceB, Involved in the Biosynthesis of the Cepacian Exopolysaccharide." Journal of Bacteriology 187, no. 14 (July 2005): 5013–18. http://dx.doi.org/10.1128/jb.187.14.5013-5018.2005.

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ABSTRACT The BceB protein of the cystic fibrosis mucoid isolate Burkholderia cenocepacia IST432 is proposed to catalyze the first step of the exopolysaccharide repeat unit assembly. Extracts of Escherichia coli cells overexpressing BceB were shown to contain glycosyltransferase activity and mediate incorporation of glucose-1-phosphate into membrane lipids. The amino acid sequence of BceB exhibits two conserved regions, one comprising two invariant aspartic acid residues (Asp339 and Asp355) that are essential for catalysis, as substantiated by site-directed mutagenesis, and the other comprising a putative Rossmann fold motif. The results of protein topology analysis using PhoA and LacZ fusions supported in silico predictions that BceB has at least six transmembrane segments and two major cytoplasmic loops comprising the conserved regions described above.
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Franzini, Stefano, Marco Di Stefano, and Cristian Micheletti. "essHi-C: essential component analysis of Hi-C matrices." Bioinformatics 37, no. 15 (February 1, 2021): 2088–94. http://dx.doi.org/10.1093/bioinformatics/btab062.

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Abstract Motivation Hi-C matrices are cornerstones for qualitative and quantitative studies of genome folding, from its territorial organization to compartments and topological domains. The high dynamic range of genomic distances probed in Hi-C assays reflects in an inherent stochastic background of the interactions matrices, which inevitably convolve the features of interest with largely non-specific ones. Results Here, we introduce and discuss essHi-C, a method to isolate the specific or essential component of Hi-C matrices from the non-specific portion of the spectrum compatible with random matrices. Systematic comparisons show that essHi-C improves the clarity of the interaction patterns, enhances the robustness against sequencing depth of topologically associating domains identification, allows the unsupervised clustering of experiments in different cell lines and recovers the cell-cycle phasing of single-cells based on Hi-C data. Thus, essHi-C provides means for isolating significant biological and physical features from Hi-C matrices. Availability and implementation The essHi-C software package is available at https://github.com/stefanofranzini/essHIC. Supplementary information Supplementary data are available at Bioinformatics online.
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Dahekar, Swati M., and Yogesh Bhute. "An Efficient Risk-Aware Distributed Control System to Minimize Routing Attacks on MANET." Journal of Advance Research in Computer Science & Engineering (ISSN: 2456-3552) 2, no. 3 (March 31, 2015): 01–07. http://dx.doi.org/10.53555/nncse.v2i3.457.

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The topological nature of MANET(Mobile Ad-hoc Network) itself demands high security due to its mobility movement, but designing a risk aware routing path for MANET is a complex task because of its Dynamic nature of Infrastructure. In this proposal, designing an Dynamic routing path decider to find less risk aware routing path for effective communication. The efficiency of the throughput and Routing failures can be further reduced by making Nodes of MANET to be more Knowledgeable that is with more Metadata parameters. This paper introduce a class of metrics to measure the effective security offered in a wireless network as a function of the routing topology and the link security provided by the key assignment protocol. This joint protocol analysis allows a network analyst or an adversary to evaluate the vulnerability of network traffic and isolate weakly secured connections. Its show how an intelligent adversary can mount a node capture attack using vulnerability evaluation to focus the attack on the nodes which contribute maximally to the compromise of network traffic.
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Huzsvár, Tamás, Richárd Wéber, and Csaba János Hős. "Analysis of the Segment Graph of Water Distribution Networks." Periodica Polytechnica Mechanical Engineering 63, no. 4 (June 28, 2019): 295–300. http://dx.doi.org/10.3311/ppme.13739.

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One of the basic infrastructures of every settlement is the water distribution system, which provides clean and potable water for both private houses, industrial consumers and institution establishments. The operational robustness and vulnerabilities of these networks is an essential issue, both for the quality of life and for the preservation of the environment. Even with frequent and careful maintenance, unintentional pipe bursts might occur, and during the reparation time, the damaged section must be isolated hydraulically from the main body of the water distribution network. Due to the size and complexity of these networks, it might not be trivial how to isolate the burst section, especially if one wishes to minimize the impact on the overall system. This paper presents an algorithmic method that is capable of creating isolation plans for real-life networks in a computationally efficient way, based on the graph properties of the network. Besides this segmentation plan, the topological behavior of the structural graph properties was analyzed with the help of the complex network theory to create a method for the quantitative topology based categorization of the water distribution networks.
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Harrison, Jerry Joe E. K., Moscoh Daniel Ayine-Tora, Benjamin Appiagyei, Felix C. Mills-Robertson, William A. Asomaning, Daniel G. Achel, Hiroyuki Ishida, and Robert Kingsford-Adaboh. "Crystal structure and in vitro antimicrobial activity studies of Robustic acid and other Alpinumisoflavones isolated from Millettia thonningii." Zeitschrift für Kristallographie - Crystalline Materials 234, no. 4 (April 24, 2019): 229–35. http://dx.doi.org/10.1515/zkri-2018-2052.

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Abstract We report a systematic study of the antibacterial inhibitory potential of isoflavone natural products isolated from the seeds extracts of Millettia thonningii. In an effort to gain bond topological information which may have consequences for the observed bioactivities, the crystal structure of robustic acid was solved and refined using the independent atom as well as the invariom model, and the structures were compared. Robustic acid contains a fused tricyclic unit with a benzopyran moiety, with a phenylene ring substitution on the coumarin ring similar to the alpinumisoflavones isolated from this plant. At a minimum inhibitory concentration of ~1 mg/mL, alpinumisoflavone and robustic acid were found to be cytotoxic to Staphylococcus aureus (ATCC 25923) showing a zone of inhibition (ZOI) of ~9 mm. On the other hand, at ~2 mg/mL, these compounds were found to be bacteriostatic to a hospital isolate of Salmonella typhi with about 7 mm ZOI. Taken together, these compounds offer potential new avenues for targeting both Gram positive and negative bacteria and could be useful as chemical probes for understanding these pathogens in an effort to overcome drug resistance.
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HAMID, A. S. "ELECTRONIC STRUCTURE AND FERMI SURFACE OF THE QUATERNARY INTERMETALLIC BOROCARBIDE SUPERCONDUCTOR YNi2B2C FROM 2D-ACAR." International Journal of Modern Physics B 17, no. 31n32 (December 30, 2003): 5973–82. http://dx.doi.org/10.1142/s0217979203023616.

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We measured the angular momentum density distribution of YNi 2 B 2 C to acquire information about its electronic structure. The measurements were performed using the full-scale utility of the two-dimensional angular correlation of annihilation radiation (2D-ACAR). The measured spectra clarified that Ni (3d) like state, predominantly, affected the Fermi surface of YNi 2 B 2 C . Further, s- and p-like-states enhanced its superconducting properties. The Fermi surface of YNi 2 B 2 C . was reconstructed using Fourier transformation followed by the LCW (Loucks, Crisp and West) folding procedure. It showed a large and complex surface similar to that of the high temperature superconductors HTS, with anisotropic properties. It also disclosed the effect of d-like state. Nevertheless, the current Fermi surface could deliver the needed topological information to isolate its features. The general layouts of this Fermi surface are; two large electron surfaces running along Γ–Z direction; as well as an additional large electron surface centered on X point; beside one hole surface centered on 100 point. This Fermi surface was interpreted in view of the earlier results.
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24

Arslan, Sami, Ires Iskender, and Tuğba Selcen Navruz. "Finite Element Method-Based Optimisation of Magnetic Coupler Design for Safe Operation of Hybrid UAVs." Aerospace 10, no. 2 (February 2, 2023): 140. http://dx.doi.org/10.3390/aerospace10020140.

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The integration of compact concepts and advances in permanent-magnet technology improve the safety, usability, endurance, and simplicity of unmanned aerial vehicles (UAVs) while also providing long-term operation without maintenance and larger air gap use. These developments have revealed the demand for the use of magnetic couplers to magnetically isolate aircraft engines and starter-generator shafts, allowing contactless torque transmission. This paper explores the design aspects of an active cylindrical-type magnetic coupler based on finite element analyses to achieve an optimum model for hybrid UAVs using a piston engine. The novel model is parameterised in Ansys Maxwell for optimetric solutions, including magnetostatics and transients. The criteria of material selection, coupler types, and topologies are discussed. The Torque-Speed bench is set up for dynamic and static tests. The highest torque density is obtained in the 10-pole configuration with an embrace of 0.98. In addition, the loss of synchronisation caused by the piston engine shaft locking and misalignment in the case of bearing problems is also examined. The magnetic coupler efficiency is above 94% at the maximum speed. The error margin of the numerical simulations is 8% for the Maxwell 2D and 4.5% for 3D. Correction coefficients of 1.2 for the Maxwell 2D and 1.1 for 3D are proposed.
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Masciadri, Andrea, Changhong Lin, Sara Comai, and Fabio Salice. "A Multi-Resident Number Estimation Method for Smart Homes." Sensors 22, no. 13 (June 25, 2022): 4823. http://dx.doi.org/10.3390/s22134823.

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Population aging requires innovative solutions to increase the quality of life and preserve autonomous and independent living at home. A need of particular significance is the identification of behavioral drifts. A relevant behavioral drift concerns sociality: older people tend to isolate themselves. There is therefore the need to find methodologies to identify if, when, and how long the person is in the company of other people (possibly, also considering the number). The challenge is to address this task in poorly sensorized apartments, with non-intrusive sensors that are typically wireless and can only provide local and simple information. The proposed method addresses technological issues, such as PIR (Passive InfraRed) blind times, topological issues, such as sensor interference due to the inability to separate detection areas, and algorithmic issues. The house is modeled as a graph to constrain transitions between adjacent rooms. Each room is associated with a set of values, for each identified person. These values decay over time and represent the probability that each person is still in the room. Because the used sensors cannot determine the number of people, the approach is based on a multi-branch inference that, over time, differentiates the movements in the apartment and estimates the number of people. The proposed algorithm has been validated with real data obtaining an accuracy of 86.8%.
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Shamseddine, Maha, Wassim Itani, Ali Chehab, and Ayman Kayssi. "Network Programming and Probabilistic Sketching for Securing the Data Plane." Security and Communication Networks 2018 (June 28, 2018): 1–23. http://dx.doi.org/10.1155/2018/2905730.

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This paper presents VISKA, a cloud security service for dynamically detecting malicious switching elements in software defined networking (SDN) infrastructures. The main contributions of VISKA lie in (1) utilizing network programming and secure probabilistic sketching in SDN environments to dynamically detect and isolate parts of the data plane that experience malicious behavior, (2) applying a set of focused packet probing and sketching mechanisms on isolated network partitions/views rather than focusing the security mechanisms on the whole physical network, (3) efficiently analyzing the network behavior of the resulting views by recursively partitioning them in a divide-and-conquer fashion to logarithmically reduce the problem size in order to localize abnormal/malicious switching units, and (4) providing an attack categorization module that analyzes live ingress/egress traffic of the maliciously detected switch(es) solely to identify the specific type of attack, rather than inspecting the whole network traffic as is done in traditional intrusion detection systems. This significantly enhances the performance of attack detection and reduces the load on the controller. A testbed prototype implementation is realized on the Mininet network emulator. The experimental analysis corroborated the algorithms’ convergence property using the linear and FatTree topologies with network sizes of up to 250 switches. Moreover, an implementation of the attack categorization module is realized and achieved an accuracy rate of over 90% for the different attack types supported.
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DiMattina, Christopher, and Kechen Zhang. "How Optimal Stimuli for Sensory Neurons Are Constrained by Network Architecture." Neural Computation 20, no. 3 (March 2008): 668–708. http://dx.doi.org/10.1162/neco.2007.11-05-076.

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Identifying the optimal stimuli for a sensory neuron is often a difficult process involving trial and error. By analyzing the relationship between stimuli and responses in feedforward and stable recurrent neural network models, we find that the stimulus yielding the maximum firing rate response always lies on the topological boundary of the collection of all allowable stimuli, provided that individual neurons have increasing input-output relations or gain functions and that the synaptic connections are convergent between layers with nondegenerate weight matrices. This result suggests that in neurophysiological experiments under these conditions, only stimuli on the boundary need to be tested in order to maximize the response, thereby potentially reducing the number of trials needed for finding the most effective stimuli. Even when the gain functions allow firing rate cutoff or saturation, a peak still cannot exist in the stimulus-response relation in the sense that moving away from the optimum stimulus always reduces the response. We further demonstrate that the condition for nondegenerate synaptic connections also implies that proper stimuli can independently perturb the activities of all neurons in the same layer. One example of this type of manipulation is changing the activity of a single neuron in a given processing layer while keeping that of all others constant. Such stimulus perturbations might help experimentally isolate the interactions of selected neurons within a network.
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Wesley Silva, Deivid, and Fabiana Florian. "SISTEMA DE PROTEÇÃO DA REDE DE DISTRIBUIÇÃO DE ENERGIA ELÉTRICA." RECIMA21 - Revista Científica Multidisciplinar - ISSN 2675-6218 3, no. 1 (December 2, 2022): e3122422. http://dx.doi.org/10.47820/recima21.v3i1.2422.

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A segurança da rede elétrica preocupa-se tanto com a integridade física dos componentes do sistema elétrico quanto com o bem-estar daqueles que operam nele ou em seu entorno. A distribuição de eletricidade é vulnerável a uma ampla variedade de modos de falha. Eletricidade gerada por descargas atmosféricas como raios, que podem causar danos à infraestrutura elétrica. Para ser eficiente, um sistema de proteção precisa ser adequadamente dimensionado, seguro, confiável, rápido, sensível a surtos e coordenado em sua seletividade. Neste sentido, objetivou-se mostrar dois tipos de ferramentas de proteção conhecidas como protetores de rede que foram projetadas computacionalmente. Para isso, nas redes de distribuição de energia elétrica, foram instalados protetores de rede para identificar a presença de fluxo reverso de potência nos transformadores de distribuição. Essas configurações de rede proporcionam grande estabilidade no fornecimento de energia devido ao uso de pelo menos duas alimentações principais. Um curto-circuito nos alimentadores primários se manifesta como uma inversão de corrente nos transformadores desta topologia. O fluxo reverso da falta se origina das contribuições da rede secundária das outras alimentações principais. Juntamente com a proteção de sobrecorrente dos alimentadores primários, o protetor de rede ajuda a isolar completamente o curto-circuito isolando os transformadores ligados ao alimentador ausente de suas conexões com a rede secundária. Concluiu-se que os protetores de rede modelados cumprem sua função adequadamente, o crescimento da geração dispersa pode levar a ações inadequadas por parte dos protetores de rede.
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29

Fernández, Igor, David de la Vega, Amaia Arrinda, Itziar Angulo, Noelia Uribe-Pérez, and Asier Llano. "Field Trials for the Characterization of Non-Intentional Emissions at Low-Voltage Grid in the Frequency Range Assigned to NB-PLC Technologies." Electronics 8, no. 9 (September 18, 2019): 1044. http://dx.doi.org/10.3390/electronics8091044.

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The paper describes the results of a measurement campaign to characterize the non-intentional emissions (NIE) that are present in the low voltage section of the electrical grid, within the frequency range assigned to narrowband power line communications (NB-PLC), from 20 kHz to 500 kHz. These NIE may severely degrade the quality of the communications and, in some cases, even isolate the transmission devices. For this reason, the identification and characterization of these perturbations are important aspects for the proper performance of the smart grid services based on PLC. The proper characterization of NIE in this frequency range is a key aspect for the selection of efficient configurations to find the best trade-off between data throughput and robustness, or even for the definition of new improved error detection and correction methods. The huge number of types of NIE, together with the wide variety of grid topologies and loads distribution (density and location of homes and industrial facilities) are great challenges that complicate the thorough characterization of NIE. This work contributes with results from field trials in different scenarios, the identification of different types of NIE and the characterization both in time and frequency domains of all the registered disturbances. This contribution will be helpful for a better knowledge of the electrical grid as a transmission medium for PLC and, therefore, for evaluating the appropriateness of different robustness techniques to be applied in the next generation of smart grid services.
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30

Oberste, M. Steven, Silvia Peñaranda, and Mark A. Pallansch. "RNA Recombination Plays a Major Role in Genomic Change during Circulation of Coxsackie B Viruses." Journal of Virology 78, no. 6 (March 15, 2004): 2948–55. http://dx.doi.org/10.1128/jvi.78.6.2948-2955.2004.

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ABSTRACT RNA recombination has been shown to occur during circulation of enteroviruses, but most studies have focused on poliovirus. To examine the role of recombination in the evolution of the coxsackie B viruses (CVB), we determined the partial sequences of four genomic intervals for multiple clinical isolates of each of the six CVB serotypes isolated from 1970 to 1996. The regions sequenced were the 5′-nontranslated region (5′-NTR) (350 nucleotides [nt]), capsid (VP4-VP2, 416 nt, and VP1, ∼320 nt), and polymerase (3D, 491 nt). Phylogenetic trees were constructed for each genome region, using the clinical isolate sequences and those of the prototype strains of all 65 enterovirus serotypes. The partial VP1 sequences of each CVB serotype were monophyletic with respect to serotype, as were the VP4-VP2 sequences, in agreement with previously published studies. In some cases, however, incongruent tree topologies suggested that intraserotypic recombination had occurred between the sequenced portions of VP2 and VP1. Outside the capsid region, however, isolates of the same serotype were not monophyletic, indicating that recombination had occurred between the 5′-NTR and capsid, the capsid and 3D, or both. Almost all clinical isolates were recombinant relative to the prototype strain of the same serotype. All of the recombination partners appear to be members of human enterovirus species B. These results suggest that recombination is a frequent event during enterovirus evolution but that there are genetic restrictions that may influence recombinational compatibility.
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31

Zhao, Le, Ahmed Abdul Moiz, Sibendu Som, Navin Fogla, Michael Bybee, Syed Wahiduzzaman, Mohsen Mirzaeian, Federico Millo, and Janardhan Kodavasal. "Examining the role of flame topologies and in-cylinder flow fields on cyclic variability in spark-ignited engines using large-eddy simulation." International Journal of Engine Research 19, no. 8 (September 27, 2017): 886–904. http://dx.doi.org/10.1177/1468087417732447.

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In this work, we have studied cycle-to-cycle variation in a spark-ignited engine using large-eddy simulation in conjunction with the G-equation combustion model. A single cylinder of a four-cylinder port-fueled spark-ignited engine was simulated. A total of 49 consecutive full cycles were computed. The operating condition studied in this work is stoichiometric and stable and represents a load of 16 bar brake mean effective pressure and an engine speed of 2500 r/min. The computational fluid dynamics simulation shows good agreement in terms of in-cylinder pressure prediction with respect to the experiments and is also able to capture the range of cycle-to-cycle variation observed in experiments. Furthermore, neither the simulation nor the experiments show any distinguishable pattern in the sequence of high and low cycles. We numerically decoupled the effects of variations in equivalence ratio fields and velocity fields to isolate the effects of differences in the velocity field and differences in the equivalence ratio field on flame development and propagation. Based on this study, we inferred that for this engine, under the operating conditions studied, the differences in burn rates can be attributed to the differences in the velocity flow-field in the region around the spark gap during ignition. We then performed an analysis to identify the correlation between peak cylinder pressure and flame topologies over all the simulated cycles. We found that high cycles (higher peak cylinder pressure values) are strongly correlated to flatter flame volume shapes (flattened in the piston-to-head direction) and volumes that are more symmetric about the ignition axis. In addition, these kinds of flame volumes were found to correlate well with lower values of prior-to-ignition velocity going from the intake to the exhaust side (mean flow caused by tumble) at the spark and also higher values of prior-to-ignition velocity in the piston-to-head direction.
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32

Zhang, Huan, Debashish Bhattacharya, Lucie Maranda, and Senjie Lin. "Mitochondrial cob and cox1 Genes and Editing of the Corresponding mRNAs in Dinophysis acuminata from Narragansett Bay, with Special Reference to the Phylogenetic Position of the Genus Dinophysis." Applied and Environmental Microbiology 74, no. 5 (December 28, 2007): 1546–54. http://dx.doi.org/10.1128/aem.02103-07.

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ABSTRACT Dinophysis acuminata cells were isolated from Narragansett Bay water samples in June 2005 using flow cytometry. Dinoflagellate-specific PCR primers were used to isolate small-subunit rRNA (18S rRNA), mitochondrial cytochrome b (cob), and cytochrome c oxidase I (cox1) genes and the encoded cDNAs. Maximum-likelihood analysis of a concatenated data set of ribosomal DNA and cDNA sequences of cob and cox1 showed that D. acuminata was sister to Gonyaulacoids, but without strong bootstrap support. The approximately unbiased test could not reject alternative positions of D. acuminata. To gain better resolution, mRNA editing of cob and cox1 was inferred for D. acuminata and 13 other dinoflagellate species. The location and type of editing as well as the distribution pattern in D. acuminata were generally similar to those in other dinoflagellates except for two edited sites that are unique to this species. Bayesian analyses of a matrix that recorded the location and type of editing, and of a matrix that included the protein sequences of COB and COX1 with the editing data yielded tree topologies similar to the three-gene tree but again failed to resolve the phylogenetic position of D. acuminata. However, the density of edited sites in the D. acuminata mitochondrial genes, consistent with phylogenetic trees, indicated that Dinophysis is a derived dinoflagellate lineage, diverging after other lineages such as Oxyrrhis, Amphidinium, and Symbiodinium. We demonstrate that dinoflagellate-specific PCR coupled with flow cytometry can be a useful tool to analyze genes and their transcripts from a natural dinoflagellate population.
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33

Liao, Zhiheng, Jiaren Sun, Jialin Yao, Li Liu, Haowen Li, Jian Liu, Jielan Xie, Dui Wu, and Shaojia Fan. "Self-organized classification of boundary layer meteorology and associated characteristics of air quality in Beijing." Atmospheric Chemistry and Physics 18, no. 9 (May 15, 2018): 6771–83. http://dx.doi.org/10.5194/acp-18-6771-2018.

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Abstract. Self-organizing maps (SOMs; a feature-extracting technique based on an unsupervised machine learning algorithm) are used to classify atmospheric boundary layer (ABL) meteorology over Beijing through detecting topological relationships among the 5-year (2013–2017) radiosonde-based virtual potential temperature profiles. The classified ABL types are then examined in relation to near-surface pollutant concentrations to understand the modulation effects of the changing ABL meteorology on Beijing's air quality. Nine ABL types (i.e., SOM nodes) are obtained through the SOM classification technique, and each is characterized by distinct dynamic and thermodynamic conditions. In general, the self-organized ABL types are able to distinguish between high and low loadings of near-surface pollutants. The average concentrations of PM2.5, NO2 and CO dramatically increased from the near neutral (i.e., Node 1) to strong stable conditions (i.e., Node 9) during all seasons except for summer. Since extremely strong stability can isolate the near-surface observations from the influence of elevated SO2 pollution layers, the highest average SO2 concentrations are typically observed in Node 3 (a layer with strong stability in the upper ABL) rather than Node 9. In contrast, near-surface O3 shows an opposite dependence on atmospheric stability, with the lowest average concentration in Node 9. Analysis of three typical pollution months (i.e., January 2013, December 2015 and December 2016) suggests that the ABL types are the primary drivers of day-to-day variations in Beijing's air quality. Assuming a fixed relationship between ABL type and PM2.5 loading for different years, the relative (absolute) contributions of the ABL anomaly to elevated PM2.5 levels are estimated to be 58.3 % (44.4 µg m−3) in January 2013, 46.4 % (22.2 µg m−3) in December 2015 and 73.3 % (34.6 µg m−3) in December 2016.
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34

Mookkaiah, Gomathi Jeyam, and Ramanibai Ravichandran. "Phylogenetic information of freshwater copepod (Diaptomus sicilis) with special reference to 18S rRNA." International Journal of Biological Research 4, no. 1 (March 12, 2016): 25. http://dx.doi.org/10.14419/ijbr.v4i1.5836.

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<p>In the present investigation to isolate freshwater calanoid copepods (<em>Diaptomus sicilis</em>) was characterized and identify the organisms by 18S rRNA sequencing. Plankton samples containing <em>D. sicilis</em> were collected during January 2014 (Post-monsoon) from Madippakkam Lake (12°57'41"N80°11'27"E) Chennai, Tamil Nadu. Immediately after sampling, specimens for genetic analyses were fixed in 95% ethyl alcohol. The total DNA was extracted from the individual copepod <em>D. sicilis</em> using Qiagen Blood tissue kit. The nuclear small subunit 18S rRNA gene was amplified using the Universal primer LCO —1490 (5’-GGTCAACAAATCATAAAGATATTGG-3’) and HCO-2198 (5’-TAAACTTCAGGGTGACCAAAAAATCA-3’). PCR products were loaded onto a 1% TAE agarose gel. Sequences were carried out an automated sequencer. The nucleotide sequence of 1282 base pair region of 18S rRNA was determined for D. sicilis. The similarity of sequences of <em>D. sicilis</em> was retrieved by BLASTn pro­gram and maximum identity and E-value was 76% and 0.00, respectively. The PCR products of <em>D. sicilis</em> individuals showed 80% similarity with the partial nuclear small subunit 18S rRNA gene region of other calanoid copepods. Based on molecular data the freshwater Calanoid copepods showed different algorithms and similar types of topologies useful for designing molecular analyses using phylogeny tree construction.Present molecular stud­ies on the relationship of D. sicilis with other freshwater calanoid copepods indicate that this species is close to <em>D. castor</em> followed by <em>D. keniraensis</em><em>.</em></p>
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Pham, Minh-Tam N., Michael C. Haffner, Heather C. Wick, Jonathan B. Coulter, Anuj Gupta, Roshan V. Chikarmane, Harshath Gupta, Sarah Wheelan, William G. Nelson, and Srinivasan Yegnasubramanian. "Abstract 680: Topoisomerase 2 beta facilitates chromatin reorganization during Androgen Receptor induced transcription and contributes to chromoplexy in prostate cancer." Cancer Research 82, no. 12_Supplement (June 15, 2022): 680. http://dx.doi.org/10.1158/1538-7445.am2022-680.

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Abstract Prostate cancer (PCa) is the most common malignancy and second leading cause of cancer death in American men. Androgen Receptor (AR) mediated transcriptional program is central to normal prostate homeostasis and drives PCa growth and survival. Chromoplexy, a highly complex genomic architecture with several intra- and inter-chromosomal segments joined in a chain, is among the most prominent genetic alterations that drive both prostate cancer initiation and progression, and often involves sites of AR transcription. Previous studies have shown that AR induced, topoisomerase 2 beta (TOP2B) mediated double strand breaks were recombinogenic and led to de novo formation of TMPRSS2-ERG fusion gene, shedding light on the potential role of TOP2B in chromoplexy formation. However, the precise role of TOP2B in AR transcription was not well understood. Here, we hypothesize that TOP2B is recruited to resolve topological constraints arising during induction of AR transcriptional programs, and its catalytic activity is required to facilitate or maintain chromosomal interactions optimal for transcriptional induction. We performed Chromosomal Conformation Capture related techniques (3C and HiC) on LNCaP cells before and after androgen stimulation and observed an increase in chromatin interactions within 15kb from promoters of AR target genes upon androgen induction. These interactions depended on TOP2B, as TOP2B catalytic inhibition or knockdown reduced them significantly. Furthermore, TOP2B Hi-CHIP revealed that TOP2B is involved in key enhancer-promoter looping and in several interactions among gene body, enhancers, promoters of AR target genes, and nearby topological associated domain borders. We went on to isolate which steps during AR transcription induction required TOP2B by examining chromatin localization of the key factors, including AR, cohesin (SMC1A), CTCF, histone 3 lysine 27 acetylation (H3K27ac), and total and phosphorylated RNA Polymerase II (RNAPII) using ChIP-seq. These experiments revealed that TOP2B was not required for AR binding nor for localization of H3K27ac marks. However, it was required for recruitment of cohesin to AR binding sites as well as to AR target gene promoters and gene bodies, for displacement of CTCF near AR target genes, and for localization and phosphorylation of RNAPII at AR target genes. These data nominate TOP2B as a key AR coactivator, assisting in the proper assembly of cohesin during transcription induction, and maintaining chromosomal interactions optimal for binding and activation of RNAPII. Intriguingly, sites of binding of TOP2B, as well as of cohesin, were highly associated with sites of chromoplexy complex rearrangements in human prostate cancers. Taken together, this work elucidates the role of TOP2B in AR-induced transcription, and implicates its involvement in chromoplexy formation in PCa. Citation Format: Minh-Tam N. Pham, Michael C. Haffner, Heather C. Wick, Jonathan B. Coulter, Anuj Gupta, Roshan V. Chikarmane, Harshath Gupta, Sarah Wheelan, William G. Nelson, Srinivasan Yegnasubramanian. Topoisomerase 2 beta facilitates chromatin reorganization during Androgen Receptor induced transcription and contributes to chromoplexy in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 680.
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36

Stewart, Jane E., Mee-Sook Kim, Robert L. James, R. Kasten Dumroese, and Ned B. Klopfenstein. "Molecular Characterization of Fusarium oxysporum and Fusarium commune Isolates from a Conifer Nursery." Phytopathology® 96, no. 10 (October 2006): 1124–33. http://dx.doi.org/10.1094/phyto-96-1124.

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Fusarium species can cause severe root disease and damping-off in conifer nurseries. Fusarium inoculum is commonly found in most container and bareroot nurseries on healthy and diseased seedlings, in nursery soils, and on conifer seeds. Isolates of Fusarium spp. can differ in virulence; however, virulence and colony morphology are not correlated. Forty-one isolates of Fusarium spp., morphologically indistinguishable from F. oxysporum, were collected from nursery samples (soils, healthy seedlings, and diseased seedlings). These isolates were characterized by amplified fragment length polymorphism (AFLP) and DNA sequencing of nuclear rDNA (internal transcribed spacer including 5.8S rDNA), mitochon-drial rDNA (small subunit [mtSSU]), and nuclear translation elongation factor 1-alpha. Each isolate had a unique AFLP phenotype. Out of 121 loci, 111 (92%) were polymorphic; 30 alleles were unique to only highly virulent isolates and 33 alleles were unique to only isolates nonpathogenic on conifers. Maximum parsimony and Bayesian analyses of DNA sequences from all three regions and the combined data set showed that all highly virulent isolates clearly separated into a common clade that contained F. commune, which was recently distinguished from its sister taxon, F. oxysporum. Interestingly, all but one of the nonpathogenic isolates grouped into a common clade and were genetically similar to F. oxysporum. The AFLP cladograms had similar topologies when compared with the DNA-based phylograms. Although all tested isolates were morphologically indistinguishable from F. oxysporum based on currently available monographs, some morphological traits can be plastic and unreliable for identification of Fusarium spp. We consider the highly virulent isolates to be F. commune based on strong genetic evidence. To our knowledge, this is the first reported evidence that shows F. commune is a cause of Fusarium disease (root rot and dampingoff) on Douglas-fir seedlings. Furthermore, several AFLP genetic markers and mtSSU sequences offer potential for development of molecular markers that could be used to detect and distinguish isolates of F. oxysporum nonpathogenic to conifers and highly virulent isolates of F. commune in forest nurseries.
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37

Lewis Roberts, E., and J. F. White. "Black Choke Disease Caused by an Ephelis sp. on Purple Fountain Grass in Maryland." Plant Disease 90, no. 1 (January 2006): 112. http://dx.doi.org/10.1094/pd-90-0112a.

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Purple fountain grass (Pennisetum alopecuroides) is indigenous to Asia, prized for its foxtail-like purple flowers, and widely used as an ornamental. During October 1999, black choke disease was found on P. alopecuroides cv. Hameln (L.) Spreng at a plant nursery in Maryland. Disease symptoms include mummification of inflorescences by black conidial stromata, distorted leaf tissue, and a dense layer of white epiphytic mycelium on the adaxial leaves and culms. Stromata were initially white but became black with age. Microscopic analysis of the isolated fungus indicated that the causal organism was an Ephelis sp., American Type Culture Collection No. MYA-3317. The ephelidial conidia developed in sporodochia on stromata and were hyaline, filiform to acicular, and 18 to 21 × 1 μm. Cultures on potato dextrose agar were off-white and 50 mm in diameter after 14 days at 23°C. Analysis of herbarium specimens of several Balansia spp. revealed that the Ephelis sp. isolate bears morphological resemblance to Asian and not American Balansieae. In fact, the infection observed on Pennisetum sp. forms similarly to Ephelis sp. infection on Oryza sativa L. (Asian) that also results in development of stromata on panicles and a mycelial network enclosing the panicles, preventing maturation and expansion. On both plants, the infected inflorescence becomes black with age and appears mummified as pseudosclerotia form. Furthermore, flag leaves and tillers of both plants appear slightly distorted and silver due to the epibiotic mycelia. The causal agent of black choke disease on rice is Ephelis oryzae Syd. (teleomorph = Balansia oryzae-sativae Hashioka). The mature stroma of E. oryzae forms on the inflorescence and is embedded with a layer of ovate perithecia. Immature stromata bear conidiomata that are cupulate to cushion shaped and black, producing hyaline, branched conidiophores that terminate in phialides. Conidia are ephelidial, filiform to acicular, hyaline, and 18 to 22 × 1.5 μm (2). To determine the phylogenetic relationship between other balansioid fungi and the Ephelis sp. isolate, the nuclear ribosomal internal transcribed spacer (ITS1) region was amplified with primers ITS4 and ITS5 (3). Maximum parsimony analysis of the ITS1 sequences showed that the Ephelis sp. infecting P. alopecuroides cv. Hameln grouped (100% bootstrap support) in a clade with Ephelis oryzae, Balansia sclerotica, Balansia andropogonis, and Balansia sp.; all endemic to Asia and tightly groups with the Asian rice pathogen Ephelis oryzae (100% bootstrap support). Further phylogenetic analysis using topological constraints indicated that Ephelis sp. is not appropriately grouped with American balansioid species. Since P. alopecuroides is often imported to North America from Asia (1), it is likely that Ephelis sp. on P. alopecuroides is endemic to Asia and perhaps was transported along with its host to North America. The disease ontogeny, morphology, and sequence similarities between the Ephelis sp. isolated from Pennisetum sp. and E. oryzae suggests that these fungi are evolutionarily close, sibling species, or conspecific. To our knowledge, this is the first report of choke disease on P. alopecuroides in the United States. References: (1) A. S. Hitchcock. Manual of the Grasses of the United States. A. Chase, ed. U.S. Government Print Office, Washington DC, 1951 (2) F. N. Lee and P. S. Gunnell. Udbatta. Page 29 in: Compendium of Rice Diseases. R. K. Webster and P. S. Gunnell, eds. The American Phytopathological Society, St. Paul. MN, 1992. (3) J. F. White Jr. et al. Mycologia 89:408, 1997.
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38

Carvalho, Paulo De Barros. "MEDIDAS PROVISÓRIAS." Revista de Direito Administrativo e Infraestrutura - RDAI 4, no. 12 (January 15, 2020): 385–92. http://dx.doi.org/10.48143/rdai/12.pbc.

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1.A cláusula final do parágrafo único do art. 62 da CF 1. A cláusula final do parágrafo único do art. 62 da CP (LGL\1940\2). 2. Em que espécie de veículo normativo se converte a medida provisória? 3. As relações jurídicas tributárias e a utilização de medidas provisórias.1 As medidas provisórias constituem inovação da Carta de 1988. Sob o ângulo político, diríamos que vieram compensar a União pelo desaparecimento do decreto-lei. Seu perfil jurídico, inobstante, é diverso. Bem que subordinadas aos pressupostos de relevância e urgência, são expedidas pelo Presidente da República e irradiam, de pronto, todos os efeitos para os quais estão preordenadas. O Chefe do Executivo, ao editá-las, submetê-las-á à apreciação do Congresso Nacional, de tal arte que, se aquele órgão estiver em recesso, será convocado para se reunir, extraordinariamente, no prazo de cinco dias. Este, o caput do art. 62 da CF (LGL\1988\3). Entretanto, é no parágrafo único do dispositivo que repousam aspectos de enorme importância para a compreensão do instituto: perderão eficácia, desde a edição, se não forem convertidas em lei no prazo de 30 dias, a partir de sua publicação, devendo o Congresso Nacional disciplinar as relações delas decorrentes. De logo, uma advertência tão sovada, quanto reiteradamente esquecida: os requisitos assinalados pelo legislador constituinte são para valer. Exige-se a simultaneidade de ambos, sem o que inexistirá clima jurídico para a produção da medida. Trata-se do conectivo conjuntor, expressamente representado pelo "e". A estrutura lógica da frase normativa não comporta interpretação sintática de outra ordem, reclamando que as duas proposições conjuntas se verifiquem no mundo dos fatos sociais, para que a iniciativa possa ser desencadeada. Agora, se os vocábulos urgência e relevância são portadores de conteúdo de significação de latitude ampla, sujeitos a critérios axiológicos cambiantes, que lhes dão timbre subjetivo de grande instabilidade, isto é outro problema, cuja solução demandará esforço construtivo da comunidade jurídica, especialmente do Poder Judiciário. Aquilo que devemos evitar, como singela homenagem à integridade de nossas instituições, é que tais requisitos sejam empregados acriteriosamente, sem vetor de coerência, de modo abusivo e extravagante, como acontecera com o decreto--lei. São símbolos jurídicos que padecem de anemia semântica, com sentidos difusos, mas há uma significação de base, um minimum que nos habilita a desenhar o quadro possível de suas acepções. Quanto ao mais, as questões não se simplificam. O parágrafo único exibe, de modo ostensivo, a existência do direito de o Congresso Nacional rejeitar, por conduta omissiva, a medida provisória comunicada pelo Presidente da República. Estamos diante de uma faculdade (Fp), consistente na permissão bilateral de fazer (Pp) e de não fazer (P-p). Em linguagem formalizada. teremos: Fp ≡ Pp . P-p, onde "≡" é a equivalência (bicondicional tautológico); "Fp", a faculdade jurídica de realizar a conduta "p"; "Pp"·a permissão de concretizá-la (torná-la efetiva por comissão) ; "P-p ", a permissão de não realizá-la (comportamento omissivo): e "." o conectivo que exprime a conjunção lógica (que somente será verdadeiro quando as duas proposições o forem). Desformalizando, e adaptando a fórmula à dicção constitucional, diríamos que o Congresso está investido da permissão bilateral (faculdade) de examinar a medida provisória. Poderá empreendê-lo por comissão, vale dizer, legislando no sentido de aprová-la (total ou parcialmente) ou de rejeitá-la; como terá, também, a autorização de rejeitá-la, sobre ela não legislando no período de 30 dias, manifestando-se por omissão. Esta última, aliás, é uma das alternativas da previsão constitucional, um legítimo direito de que está investido nosso Parlamento, exercendo as prerrogativas que o parágrafo único do art. 62 da Constituição lhe confere. Ora, salta aos olhos que o exercício desse direito não pode ser tolhido pelo Presidente da República, mediante a reedição da medida. Com providência desse jaez o Chefe do Executivo inibe uma explícita permissão constitucional atribuída ao Congresso que, ao rejeitar por decurso de tempo a medida encaminhada, estaria operando a autorização de não fazer, não legislar, conduta omissiva para a qual está habilitado. Dois argumentos são decisivos para afastar esta interpretação redutora de competências do Poder Legislativo: um, estritamente jurídico, nos remete ao tratamento constitucional das matérias rejeitadas, que é inequivocamente restritivo. De fato, o art. 60, § 5º, estatui que "A matéria constante de proposta de emenda rejeitada ou havida por prejudicada não pode ser objeto de nova proposta na mesma sessão legislativa". E, para que não se diga que é restritivo por considerar as emendas à Constituição, eis a mensagem do art. 67, no que toca às demais leis do sistema: "A matéria constante de projeto de lei rejeitado somente poderá constituir objeto de novo projeto, na mesma sessão legislativa, mediante proposta da maioria absoluta dos membros de qualquer das Casas do Congresso Nacional". O outro, de cunho histórico, nos recorda que a aprovação do decreto-lei pelo Parlamento brasileiro podia dar-se tanto por legislação expressa (decreto legislativo), como por decurso de prazo (conduta omissiva do Congresso). Por que, então, imaginar-se que a medida provisória escaparia desse regime? Onde o dispositivo explícito que lhe outorgue o privilégio? Não têm elas força de lei? Que significa, em linguagem jurídica, afirmar que certa figura tem força de contrato, de ato administrativo, de lei? Exprime, sem necessidade de maiores divagações, que à mencionada figura se aplica o regime jurídico de contrato, de ato administrativo, de lei. Em outras palavras, assevera-se que os princípios constitucionais e toda a trama normativa que condicionam o contrato, o ato administrativo e a lei subordinarão, igualmente, a vida jurídica da entidade, salvo os aspectos, é óbvio, inerentes a sua própria individualidade. 1.A cláusula final do parágrafo único do art. 62 da CF Uma análise mais apressada da parte final do parágrafo único do art. 62 sugere que, rejeitada a medida provisória, esta há de perder sua eficácia, a contar da publicação (efeito ex tunc), movimentando-se o Congresso Nacional para o fim de disciplinar as relações jurídicas delas decorrentes. Quem se ativer à leitura pura e simples do texto dificilmente deixará de entender que cabe ao Poder Legislativo regrar as situações jurídicas remanescentes, sempre que a proposta for rejeitada. Contudo, meditação mais atenta demonstrará logo que, havendo a perda da eficácia, contada da sua entrada em vigor, os efeitos da medida serão desfeitos. Isso, naturalmente, com relação àqueles que suportarem o desfazimento, posto que os já consumados ganharam definitividade, podendo, quando muito, estudar-se a composição dos danos porventura verificados. Se assim é, considerando-se que tais situações fogem por completo dos esquadros genéricos da previsão legislativa, em vista da extraordinária gama de eventos que podem assumir tal condição de imutabilidade jurídica, o remédio apropriado será invocar-se a prestação jurisdicional do Estado para que, mediante a expedição de normas individuais e concretas, o Poder Judiciário atenda às peculiaridades de cada caso, fazendo incidir o direito positivo nos variados tipos de concreção factual insuscetíveis de desfazimento. Tomemos o exemplo de alguém que se viu privado da liberdade, por virtude da aplicação de regra contida em medida provisória que não logrou aprovação (expressa ou tácita) pelo Parlamento. De evidência que a violação de seu direito à liberdade consolidou-se, de tal modo que a desconstituição do ato se tornou impossível. Cumpre ao prejudicado, em face da lesão de seu direito individual, buscar decisão judiciária que, não podendo recompor a situação anterior, determine a reparação do dano efetivamente praticado. Mas, convenhamos, isso dista de ser função do Poder Legislativo, mesmo porque, como já foi dito, os acontecimentos dessa natureza revestem-se de múltiplas e imprevisíveis colorações existenciais, reclamando grau de especificidade que só o Judiciário pode oferecer. Mais a mais, cometida atribuição desse tope ao Legislativo, ficaria ele entretido com assuntos que julgou irrelevantes, inoportunos ou incompatíveis, representando autêntica violência contra esse Poder da República compeli-lo a restaurar a ordem jurídica arranhada por expedientes utilizados com açodo ou imprevisão pelo Executivo. Sua missão constitucional está bem longe de ser esta. A doutrina dominante tem levantado um argumento que peleja contra a tese exposta, baseado na posição sintática da cláusula derradeira, associada que está, no conjunto frásico, à hipótese de rejeição tácita de medida provisória pelo Congresso Nacional. Tal fundamento, todavia, é precário: a topologia das orações no período da linguagem normativa nunca foi critério para ponderações desse gênero, conhecido que é o desarranjo dos comandos normativos, esparramados em desnexo pelo universo do sistema positivo. Acreditamos que a exegese dotada de maior racionalidade aponta para o caso de acolhimento da medida provisória (total ou parcialmente) pelo Congresso. Aqui, sim, há não só campo fecundo para o desempenho da função legislativa, como necessidade de imediatas providências de teor integrativo. Com efeito, ao converter-se em lei, perde a medida seu caráter provisório e ingressa, definitivamente, na ordem jurídica, suscitando então adaptações imprescindíveis para que se mantenha a harmonia e o bom funcionamento do direito positivo. A mera aceitação da medida proposta pelo Presidente da República, na sua integridade, ou na hipótese de modificações que lhe alterem a substância ou a forma, postulam do legislador outro esforço que vem a título de corolário ou de decorrência, como preferiu o constituinte. E o mencionado esforço se consubstancia em editar outras normas jurídicas que promovam os ajustes inerentes ao ingresso das primeiras, consolidando-se o equilíbrio e a funcionalidade do sistema. Daí concluirmos que a produção de regras disciplinadoras das relações delas decorrentes se aplica às medidas que encontraram apoio no Parlamento, e destina-se a adaptar a nova lei (resultado da conversão) às exigências do sistema de que passou a fazer parte, o que requer acertos internormativos de índole axiológica, sintática e semântica. Bem se vê que a medida provisória, se levada a sério, representará um perigoso instrumento para o Poder Executivo, na proporção em que lhe caiba responder pela composição dos danos emergentes, ocorridos no intervalo que vai de sua edição até a rejeição expressa ou tácita pelo Legislativo. Convocada a ressarcir os prejuízos causados, em eventos protocolarmente identificados, a União ver-se-á onerada, reiteradamente, por força de medidas provisórias mal concebidas ou propostas em termos inapropriados. Dispensável dizer que as situações formadas neste entremeio constituem-se sempre em matéria social pronta para ser absorvida pelo subsistema normativo, bastando, é claro, que desperte o interesse criativo e disciplinador do Poder Político. Aquilo que contestamos, porém, é a relação deonticamente necessária entre a rejeição tácita ou expressa da medida e o regramento dos efeitos propagados. Opostamente, tal disciplina se afigura não só importante como até indispensável, na contingência de aprovação (integral ou parcial) da medida provisória. É de lamentar-se que o próprio Congresso Nacional, numa atitude de automutilação de suas prerrogativas constitucionais, tenha adotado entendimento diverso, como se extrai da Res. 1/1989-CN, que dispõe acerca da apreciação das medidas a que se refere o art. 62 da Constituição. No parágrafo único do art. 6º desse documento está consignado que, rejeitada a matéria, seja pela não-verificação dos pressupostos, seja pelo inacolhimento do conteúdo, "a Comissão Mista elaborará Projeto de Decreto Legislativo disciplinando as relações jurídicas decorrentes da vigência da Medida, o qual terá sua tramitação iniciada na Câmara dos Deputados". 2.Em que espécie de veículo normativo se converte a Medida Provisória? Outra dúvida que não pode ser contornada, ao focalizarmos a medida provisória, está em saber como se opera sua conversão em lei e, dentro da latitude deste conceito, em que tipo de lei se transforma, ao ensejo de sua aprovação (parcial ou total). A resposta em voga é aquela que indica para uma solução pronta, porém sobremaneira singela: não havendo previsão constitucional expressa, tudo ficaria na dependência da matéria disciplinada, de tal modo que ferindo tema de lei ordinária, nesta se converteria; se o assunto for pertinente ao âmbito de competência de lei complementar, nesta espécie de diploma normativo haveria de transformar-se; e assim por diante. Esta opção interpretativa não serve. Vêmo-la como algo apressadamente construído, sem o peso e a densidade que só a reflexão detida nos grandes valores do sistema pode ensejar. Para objetá-la pensemos nos chamados princípios ontológicos: um se aplica ao direito privado: tudo que não estiver expressamente proibido está permitido; outro, ao direito público: tudo que não estiver expressamente permitido está proibido. Pois bem, em que lugar do Texto Fundamental está a regra que autoriza esse tipo de conversão? Por outro lado, sabemos que a interpretação é ato complexo, em que se encontram envolvidos atos cognoscentes e ato de decisão política, este último revelador implacável da ideologia do exegeta. Por isso mesmo, em esforço persuasivo, façamos esta outra sorte de cogitações: não foi por deleite prescritivo que o constituinte abriu a Seção VIII, dentro do capítulo reservado ao Poder Legislativo (Capítulo I, do Livro IV), tratando do Processo Legislativo. E o mínimo de razoabilidade que podemos extrair da leitura atenta dos mencionados textos leva-nos ao reconhecimento de que o legislador constituinte atribuiu funções próprias a cada um dos sete instrumentos introdutórios de normas jurídicas, previstos nos incisos do art. 59 da CF (LGL\1988\3). Lembremo-nos de que a esquematização constitucional de competências para a produção de estatutos normativos provoca distinções que não podem ser desprezadas pelo hermeneuta. Algumas dizem com o iter procedimental; outras, com a matéria sobre que devem dispor. Quanto às primeiras, a contar dos órgãos credenciados a iniciar a tramitação, passando pelas vicissitudes da discussão parlamentar, até chegar ao quórum necessário para aprovação, momento em que haverá , ou não, espaço para a sanção presidencial, os diplomas introdutores de normas jurídicas no sistema brasileiro apresentam traços de tal modo nítidos, que nos permitem diferençá-los, isolando suas peculiaridades. Corno corolário, o regime jurídico da lei complementar é diverso daquele previsto para a lei ordinária, discrepando de ambos as providências requeridas para a elaboração de lei delegada, de decreto legislativo, de resoluções e, deixadas propositadamente para o final, aquelas inerentes às emendas à Constituição. No que entende com a matéria específica acerca da qual haverão de versar, há indicações precisas que delimitam o conteúdo dos estatutos. reservando certos assuntos a esta ou àquela espécie. O § 1º do art. 68, por exemplo, impede que a lei delegada ingresse no âmbito exclusivo dos atos de competência própria do Congresso Nacional, naqueles da competência privativa da Câmara ou do Senado, bem como na matéria reservada à lei complementar e a outras enumeradas nos incs. I a III do mesmo dispositivo. Se assim é, havemos de concluir que a Carta Magna, pelo modo diferente como estabeleceu as figuras legislativas, impõe respeito às linhas jurídicas que identificam e individualizam cada qual, não sendo possível ignorá-las pela conduta que as parifica num a única classe. É de clareza meridiana que nossa Lei Fundamental não admite a intromissão do Executivo naquilo que pertencer ao domínio de incidência da lei complementar. A delegação para esse fim está proibida de maneira enfaticamente explícita. É bem de ver que não há tolerar-se que tal vedação perca seu sentido de existência pelo recurso ao precário, excepcional e discutido instrumento que é a medida provisória. Nesse rumo, as competências do Presidente da República ficariam extraordinariamente amplificadas, tese que pode consultar a interesses de cunho político ou ideológico, mas que não encontra supedâneo na visão intra-sistemática do Direito brasileiro. Interpretação dessa ordem passaria ao largo do impedimento constitucional que tranca ao Poder Executivo a via da legislação sobre matéria de lei complementar, soabrindo-lhe o perigoso atalho da medida provisória, que além do mais tem o condão de imprimir eficácia imediata aos seus dispositivos. Em contraposição formal a este modo de avaliar o alcance das indigitadas medidas, temos para nós que o expediente que o constituinte afastou das mãos do Presidente da República, por meio de lei delegada, forma legítima e tradicional de manifestação do Poder Legislativo, certamente que não o entregaria para que fosse utilizado por intermédio de medida provisória. Se, no entanto, quisermos testar as deficiências daquela interpretação que adversamos, segundo a qual a medida que verse matéria de lei complementar, se aprovada por maioria absoluta transformar-se-á em diploma dessa natureza, basta perceber que, caminhando nessa trilha, acabaremos subvertendo o quadro das espécies do processo legislativo. Sim, porque fazendo as vezes de legislador complementar, o Chefe do Executivo ingressaria não só em território que lhe é vedado, como poderia prescrever, com base no parágrafo único do art. 59 da Constituição, as disposições relativas à "elaboração, redação, alteração e consolidação das leis". Eis a confusão absoluta instalada no processo de produção legislativa no Brasil, com a medida provisória crescendo na escala hierárquica, a ponto de tornar-se fonte de validade formal das outras leis do sistema. O passo seguinte seria admitir-se a introdução de emendas à Constituição, mediante a iniciativa de medidas provisórias que viessem a ser acolhidas pelo sufrágio de três quintos dos membros das Casas do Congresso, em dois turnos de votação, consoante requer o art. 60, § 2º da CF (LGL\1988\3). 3.As relações jurídicas tributárias e a utilização de medidas provisórias Meditemos, por derradeiro, acerca do emprego de medidas provisórias no plano do direito tributário. A União poderá utilizá-la para criar tributo, estabelecer faixas adicionais de incidência em gravames já existentes ou, ainda, majorá-los? Cremos que não. E dois motivos suportam este entendimento: um, pela incompatibilidade da vigência imediata, elemento essencial à índole da medida, com o princípio da anterioridade (art. 150, III, “b” da CF (LGL\1988\3); outro, de cunho semântico e pragmático, pela concepção de "tributo" como algo sobre que os administrados devam expressar seu consentimento prévio. A noção de "tributo ", nos países civilizados, repele a exigência de parcelas do patrimônio dos indivíduos, por ação unilateral do Estado, considerando a iniciativa como fundada em ideia vetusta, que prevaleceu em tempos medievais e em ambientes de tirania. O intervalo de tempo em que vigora a medida, sem que o Poder Legislativo a aprecie, acolhendo-a, expõe os cidadãos, comprometendo direitos que lhes são fundamentais (propriedade e liberdade), expressamente garantidos na Carta Básica. Este intertempo, onde impera a vontade monádica do Estado sem o conhecimento antecipado e o assentimento dos destinatários da pretensão, não se compagina também com a magnitude semântica que o termo “tributo” ostenta nos dias atuais. Não valessem tais razões e a simples invocação do princípio da segurança do direito já seria bastante em si para inibir esse mecanismo de ação fiscal.
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39

Ilyas, Muhammad, Shawn Cui, and Marek Perkowski. "Ternary logic design in topological quantum computation." Journal of Physics A: Mathematical and Theoretical, June 22, 2022. http://dx.doi.org/10.1088/1751-8121/ac7b55.

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Abstract The quantum computer is an exponential speed up over its classical counterpart. It works on the principle of superposition. Due to the decoherence effect, the superposition of a quantum state is destroyed by interaction with the environment. It is a real challenge to completely isolate the quantum system and make it free of decoherence. This problem can be circumvented by the use of the topological quantum phases of matter with the quasiparticle excitations called anyons. The topological quantum gates are obtained by braiding and fusion of the non-Abelian anyons. The fault-tolerance is achieved through the topological degrees of freedom of anyons, which are non-local and hence inaccessible to the local perturbations. In this paper, the Hilbert space for a topological qubit is discussed. Ternary logic gates are more compact than their binary counterparts and naturally arise in a type of anyonic model called the metaplectic anyons. The mathematical model, for the fusion and braiding matrices of metaplectic anyons, is the quantum deformation of the recoupling theory. We proposed the ternary arithmetic circuits with reduced quantum cost comparing with the existing realizations. Their implementation in topological quantum computation is explained using the gates based on braiding and the topological charge measurement of the metaplectic anyons.
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40

Davies, Misty, and Adrian Lew. "Tests of the Affinity Assumption in Phantomlike Elastomer Networks." MRS Proceedings 1190 (2009). http://dx.doi.org/10.1557/proc-1190-nn11-38.

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AbstractPhantomlike elastomer simulations do not always deform globally affinely in the way that classical theory predicts. Assuming that each crosslink will deform affinely with its topological neighbors gives much better results, and creates a way to isolate crosslinks with unpredictable deformation properties. The correlation of non-affinities and network properties depends on the constitutive model and boundary condition used. We always find a correlation between local density of crosslinks and degree of non-affinity.
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41

Schierholz, Gerrit. "Strong CP problem, electric dipole moment, and fate of the axion." SciPost Physics Proceedings, no. 6 (May 31, 2022). http://dx.doi.org/10.21468/scipostphysproc.6.011.

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Three hard problems! In this talk I investigate the long-distance properties of quantum chromodynamics in the presence of a topological \mathbf{\theta}𝛉 term. This is done on the lattice, using the gradient flow to isolate the long-distance modes in the functional integral measure and tracing it over successive length scales. It turns out that the color fields produced by quarks and gluons are screened, and confinement is lost, for vacuum angles \mathbf{|\theta| > 0}|𝛉|>0, thus providing a natural solution of the strong CP problem. This solution is compatible with recent lattice calculations of the electric dipole moment of the neutron, while it excludes the axion extension of the Standard Model.
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42

Kovalev, S., K. J. Tielrooij, J. C. Deinert, I. Ilyakov, N. Awari, M. Chen, A. Ponomaryov, et al. "Terahertz signatures of ultrafast Dirac fermion relaxation at the surface of topological insulators." npj Quantum Materials 6, no. 1 (October 1, 2021). http://dx.doi.org/10.1038/s41535-021-00384-9.

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AbstractTopologically protected surface states present rich physics and promising spintronic, optoelectronic, and photonic applications that require a proper understanding of their ultrafast carrier dynamics. Here, we investigate these dynamics in topological insulators (TIs) of the bismuth and antimony chalcogenide family, where we isolate the response of Dirac fermions at the surface from the response of bulk carriers by combining photoexcitation with below-bandgap terahertz (THz) photons and TI samples with varying Fermi level, including one sample with the Fermi level located within the bandgap. We identify distinctly faster relaxation of charge carriers in the topologically protected Dirac surface states (few hundred femtoseconds), compared to bulk carriers (few picoseconds). In agreement with such fast cooling dynamics, we observe THz harmonic generation without any saturation effects for increasing incident fields, unlike graphene which exhibits strong saturation. This opens up promising avenues for increased THz nonlinear conversion efficiencies, and high-bandwidth optoelectronic and spintronic information and communication applications.
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43

REID, COLIN D., PHILLIP R. WESOLEK, and FRANÇOIS LE MAÎTRE. "Chief factors in Polish groups." Mathematical Proceedings of the Cambridge Philosophical Society, June 30, 2021, 1–58. http://dx.doi.org/10.1017/s0305004121000505.

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Abstract In finite group theory, chief factors play an important and well-understood role in the structure theory. We here develop a theory of chief factors for Polish groups. In the development of this theory, we prove a version of the Schreier refinement theorem. We also prove a trichotomy for the structure of topologically characteristically simple Polish groups. The development of the theory of chief factors requires two independently interesting lines of study. First we consider injective, continuous homomorphisms with dense normal image. We show such maps admit a canonical factorisation via a semidirect product, and as a consequence, these maps preserve topological simplicity up to abelian error. We then define two generalisations of direct products and use these to isolate a notion of semisimplicity for Polish groups.
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44

Hou, Zhiqiang, Dailu Chen, Bryan D. Ryder, and Lukasz A. Joachimiak. "Biophysical properties of a tau seed." Scientific Reports 11, no. 1 (June 30, 2021). http://dx.doi.org/10.1038/s41598-021-93093-z.

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AbstractPathogenesis of tauopathies involves conversion of tau monomer into pathological tau conformers that serve as templates to recruit native tau into growing assemblies. Small soluble tau seeds have been proposed to drive pathological tau assembly in vitro, in cells and in vivo. We have previously described the isolation of monomeric pathogenic tau seeds derived from recombinant samples and tauopathy tissues but in-depth biophysical characterization of these species has not been done. Here we describe a chromatographic method to isolate recombinant soluble tau seeds derived from heparin treatment. We used biochemical and biophysical approaches to show that the seeds are predominantly monomeric and have the capacity to nucleate aggregation of inert forms of tau in vitro and in cells. Finally, we used crosslinking mass spectrometry to identify the topological changes in tau as it converts from an inert state to a pathogenic seed. Future studies will reveal the relationship between soluble seeds and structural polymorphs derived from tauopathies to help diagnose and develop therapeutics targeting specific tauopathies.
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45

Beaulieu, Samuel, Michael Schüler, Jakub Schusser, Shuo Dong, Tommaso Pincelli, Julian Maklar, Alexander Neef, et al. "Unveiling the orbital texture of 1T-TiTe2 using intrinsic linear dichroism in multidimensional photoemission spectroscopy." npj Quantum Materials 6, no. 1 (November 15, 2021). http://dx.doi.org/10.1038/s41535-021-00398-3.

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AbstractThe momentum-dependent orbital character in crystalline solids, referred to as orbital texture, is of capital importance in the emergence of symmetry-broken collective phases, such as charge density waves as well as superconducting and topological states of matter. By performing extreme ultraviolet multidimensional angle-resolved photoemission spectroscopy for two different crystal orientations linked to each other by mirror symmetry, we isolate and identify the role of orbital texture in photoemission from the transition metal dichalcogenide 1T-TiTe2. By comparing our experimental results with theoretical calculations based on both a quantitative one-step model of photoemission and an intuitive tight-binding model, we unambiguously demonstrate the link between the momentum-dependent orbital orientation and the emergence of strong intrinsic linear dichroism in the photoelectron angular distributions. Our results represent an important step towards going beyond band structure (eigenvalues) mapping and learning about electronic wavefunction and orbital texture of solids by exploiting matrix element effects in photoemission spectroscopy.
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46

Back, Jaime Andre, Juliano Schirmbeck, Jeferson Gaio, and Lírio Schaeffer. "Utilização de simulação computacional para o estudo das propriedades eletromagnéticas de um compósito magnético macio (smc) para futuras aplicações em motores de indução." Tecno-Lógica 24, no. 1 (January 13, 2020). http://dx.doi.org/10.17058/tecnolog.v24i1.13747.

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Este trabalho apresenta o desenvolvimento de um método de simulação computacional para o estudo das propriedades eletromagnéticas de um material compósito para aplicação em motores de indução (rotor e estator), motivado pela possibilidade de aplicação dos materiais SMCs (Soft Magnetic Composites) como alternativa aos aços elétricos tradicionais (laminado de grão não orientado). Desta forma, objetivou-se o desenvolvimento de um ambiente de simulação computacional afim de facilitar o levantamento dos parâmetros elétricos e magnéticos de um motor de indução, sem a necessidade da construção de um modelo físico. Para esta tarefa, utilizou-se o software FEMM 4.2 para as simulações do modelo em 2D, bem como para validar os parâmetros coletados em comparação aos materiais comerciais de mesma composição. Uma relação entre a circulação de fluxo magnético nos materiais SMCs e nas chapas laminadas foi feita, na qual observou-se que a amostra de material compósito possuía propriedades compatíveis aos aços laminados, porém uma resistividade elétrica maior devido a camada isolante das partículas ser mais espessa. Como resultado final, pode-se levantar um método de simulação de forma a facilitar a pesquisa e desenvolvimento de diferentes ligas de pó de Fe, que poderão utilizadas em novas topologias de motores elétricos de indução, para as mais diferentes aplicações industriais.
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47

Ford, J., D. Kafetsouli, H. Wilson, C. Udeh-Momoh, M. Politis, S. AhmadiAbhari, I. Rabiner, and L. T. Middleton. "At a Glance: An Update on Neuroimaging and Retinal Imaging in Alzheimer’s Disease and Related Research." Journal Of Prevention of Alzheimer's Disease, 2022, 1–10. http://dx.doi.org/10.14283/jpad.2022.7.

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Neuroimaging serves a variety of purposes in Alzheimer’s disease (AD) and related dementias (ADRD) research - from measuring microscale neural activity at the subcellular level, to broad topological patterns seen across macroscale-brain networks, and everything in between. In vivo imaging provides insight into the brain’s structure, function, and molecular architecture across numerous scales of resolution; allowing examination of the morphological, functional, and pathological changes that occurs in patients across different AD stages (1). AD is a complex and potentially heterogenous disease, with no proven cure and no single risk factor to isolate and measure, whilst known risk factors do not fully account for the risk of developing this disease (2). Since the 1990’s, technological advancements in neuroimaging have allowed us to visualise the wide organisational structure of the brain (3) and later developments led to capturing information of brain ‘functionality’, as well as the visualisation and measurement of the aggregation and accumulation of AD-related pathology. Thus, in vivo brain imaging has and will continue to be an instrumental tool in clinical research, mainly in the pre-clinical disease stages, aimed at elucidating the biological complex processes and interactions underpinning the onset and progression of cognitive decline and dementia. The growing societal burden of AD/ADRD means that there has never been a greater need, nor a better time, to use such powerful and sensitive tools to aid our understanding of this undoubtedly complex disease. It is by consolidating and reflecting on these imaging advancements and developing long-term strategies across different disciplines, that we can move closer to our goal of dementia prevention. This short commentary will outline recent developments in neuroimaging in the field of AD and dementia by first describing the historical context of AD classification and the introduction of AD imaging biomarkers, followed by some examples of significant recent developments in neuroimaging methods and technologies.
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48

Liu, Shanshan, Xiaoliang Li, Zhenfei Guo, Hongsheng Liu, Yu Sun, Yudong Liu, Qinglong Wang, Shengkai Liao, and Kai Zhang. "A Core Genome Multilocus Sequence Typing Scheme for Streptococcus mutans." mSphere 5, no. 4 (July 8, 2020). http://dx.doi.org/10.1128/msphere.00348-20.

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ABSTRACT Streptococcus mutans is one of the primary pathogens responsible for the development of dental caries. Recent whole-genome sequencing (WGS)-based core genome multilocus sequence typing (cgMLST) approaches have been employed in epidemiological studies of specific human pathogens. However, this approach has not been reported in studies of S. mutans. Here, we therefore developed a cgMLST scheme for S. mutans. We surveyed 199 available S. mutans genomes as a means of identifying cgMLST targets, developing a scheme that incorporated 594 targets from the S. mutans UA159 reference genome. Sixty-eight sequence types (STs) were identified in this cgMLST scheme (cgSTs) in 80 S. mutans isolates from 40 children that were sequenced in this study, compared to 35 STs identified by multilocus sequence typing (MLST). Fifty-six cgSTs (82.35%) were associated with a single isolate based on our cgMLST scheme, which is significantly higher than in the MLST scheme (11.43%). In addition, 58.06% of all MLST profiles with ≥2 isolates were further differentiated by our cgMLST scheme. Topological analyses of the maximum likelihood phylogenetic trees revealed that our cgMLST scheme was more reliable than the MLST scheme. A minimum spanning tree of 145 S. mutans isolates from 10 countries developed based upon the cgMLST scheme highlighted the diverse population structure of S. mutans. This cgMLST scheme thus offers a new molecular typing method suitable for evaluating the epidemiological distribution of this pathogen and has the potential to serve as a benchmark for future global studies of the epidemiological nature of dental caries. IMPORTANCE Streptococcus mutans is regarded as a major pathogen responsible for the onset of dental caries. S. mutans can transmit among people, especially within families. In this study, we established a new epidemiological approach to S. mutans classification. This approach can effectively differentiate among closely related isolates and offers superior reliability relative to that of the traditional MLST molecular typing method. As such, it has the potential to better support effective public health strategies centered around this bacterium that are aimed at preventing and treating dental caries.
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