530 research outputs found

    Measuring Topological Field Theories: Lattice Models and Field-Theoretic Description

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    Recent years have witnessed a surge of interest in performing measurements within topological phases of matter, e.g., symmetry-protected topological (SPT) phases and topological orders. Notably, measurements of certain SPT states have been known to be related to Kramers-Wannier duality and Jordan-Wigner transformations, giving rise to long-range entangled states and invertible phases, such as the Kitaev chain. Moreover, measurements of topologically ordered states correspond to charge condensations. In this work, we present a field-theoretic framework for describing measurements within topological field theories. We employ various lattice models as examples to illustrate the outcomes of measuring local symmetry operators within topological phases, demonstrating their agreement with the predictions from field-theoretic descriptions. We demonstrate that these measurements can lead to SPT, spontaneous symmetry-breaking, and topologically ordered phases. Specifically, when there is emergent symmetry after measurement, the remaining symmetry and emergent symmetry will have a mixed anomaly, which leads to long-ranged entanglement.Comment: 43 page

    Dual description of η-deformed OSP sigma models

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    We study the dual description of the η-deformed OSP(N|2m) sigma model in the asymptotically free regime (N > 2m + 2). Compared to the case of classical Lie groups, for supergroups there are inequivalent η-deformations corresponding to different choices of simple roots. For a class of such deformations we propose the system of screening charges depending on a continuous parameter b, which defines the η-deformed OSP(N|2m) sigma model in the limit b → ∞ and a certain Toda QFT as b → 0. In the sigma model regime we show that the leading UV asymptotic of the η-deformed model coincides with a perturbed Gaussian theory. In the perturbative regime b → 0 we show that the tree-level two-particle scattering matrix matches the expansion of the trigonometric OSP(N|2m) S-matrix

    Multimodal Man-machine Interface and Virtual Reality for Assistive Medical Systems

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    The results of research the intelligence multimodal man-machine interface and virtual reality means for assistive medical systems including computers and mechatronic systems (robots) are discussed. The gesture translation for disability peoples, the learning-by-showing technology and virtual operating room with 3D visualization are presented in this report and were announced at International exhibition "Intelligent and Adaptive Robots–2005"

    An Integrated Multidisciplinary Nanoscience Concentration Certificate Program for STEM Education

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    Integration of nanoscience and nanotechnology curricula into the College of Science, Mathematics, and Technology (CSMT) at the University of Texas at Brownsville (UTB) is reported. The rationale for the established multidisciplinary Nanoscience Concentration Certificate Program (NCCP) is to: (i) develop nanotechnology-relevant courses within a comprehensive Science, Engineering and Technology curriculum, and, to offer students an opportunity to graduate with a certificate in nanoscience and nanotechnology; (ii) to contribute to students\u27 success in achieving student outcomes across all college\u27s majors, and, improve the breath, depth and quality of science, technology, engineering and mathematics (STEM) graduates\u27 education; (iii) through NCCP, recruit certificate- and associate-degree seeking students into four year programs in engineering and physical sciences. A long-term goal is to develop an ABET accredited bachelor program in nanoscience. This program is expected to reach out to a large group of undergraduate students in a coordinated manner, enhance students\u27 knowledge and skills, as well as facilitate efforts of individual faculty members in STEM education. The UTB NCCP is supported by the NSF NUE program, under which we are developing and offering seven upper-level interdisciplinary undergraduate courses. These courses and program are assessed and evaluated

    Serum prevalence to non-viral pathogens in wild felids of Southern Primorye, Russia

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    Serum prevalence to six different non-viral pathogens was estimated for big Russian cats (Amur tiger (Panthera tigris altaica) and the Far Eastern leopard (Panthera pardus orientalis)) in Southern Primorye, Russia (n = 26) in 2008–2016. Serum samples from smaller cats (Eurasian lynx (Lynx lynx) and Far Eastern wildcat (Prionailurus bengalensis euptilurus)) were also tested for these pathogens (n = 28) during the same period. Felids of Russian Southern Primorye showed serum prevalence to five out of six tested pathogens. Antibodies to Candida sp. and Trichinella sp. were found to be much more widespread in cats (47% and 42%) than antibodies to other tested pathogens (20% and less). Large cats demonstrated a higher serum prevalence to these pathogens than smaller ones. We did not detect animals seropositive to Coxiella burnetii

    Abstract P-46: Structure of A. Baumannii Phage Tapaz, Revealed with Cryo-Electron Microscopy

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    Background: Acinetobacter baumannii is an opportunistic pathogen and one of the six most important multidrug resistant microorganisms in hospitals worldwide. Some of its strains are resistant to most of the antibiotics, A. baumannii is included into the Priority 1 part of Global Priority List of Antibiotic-resistant Bacteria. Phage therapy is considered to be an alternative strategy to antibiotic treatments. Methods: A. baumannii strain NIPH601 cells were grown till OD6000.4 and infected with the phage at MOI 10:1. After complete lysis took place cell debris was spined down and phage particles were precipitated with the PEG6000 (final concentration 10% PEG 6000, 0.5 NaCl). Virus particles were collected by centrifugation, resuspended at SM buffer and applied on CsCl step gradient. Gradient was spinned down for 2 hours at 40000g and the fraction containing phage particles was collected and dialyzed against SM buffer. Purified phage particles were applied to Quantifoil 1.2/1.3 grids and plunge-froze in Vitrobot Mark IV (TFS) Micrographs were collected in HKU, Shenzhen campus with Titan Krios cryoelectron microscope (TFS), equipped with Gatan K3 direct electron detector. The micrographs were acquired with 1.06 Å pixel size and 1.5 um average defocus value in counting mode with 50 frames and 1.2 e/Å2/frame dose rate. All image processing was performed with Relion3.0 software, except for the particle picking step performed with cryolo. Results: Lytic A. baumannii phage TaPaz belongs to the family Myoviridae. BLAST search over NCBI “nr” (non-redundant) database revealed close homology with previously published sequences of Acinetobacter phage vB_AbaM_B9 and Acinetobacter phage BS46. However, no structural information about any homologous proteins was found among the PDB structures. The cryo-EM map was reconstructed with single particle analysis independently for the capsid, tail and baseplate regions. The capsid was reconstructed at 3.9 Å resolution with I3 symmetry applied (Fig. 1A). The baseplate region of the phage was reconstructed at 3.5 Å resolution with C3 symmetry (Fig. 1B). The tail region was reconstructed at 2.6 Å resolution with helical symmetry (Rise 36.4 Å, Twist 25.7 deg). Initial atomic model for the tail region was built from sequence with Deeptracer and was further refined in coot (Fig. 1C). Conclusion: We successfully obtained the near-atomic resolution structural map of phage TaPaz. The data obtained contribute to enhancing knowledge of structural diversity of bacterial viruses infecting A. baumannii

    Синтез енергоефективного закону управління розгоном автомобіля

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    We have established the laws of change in the vehicle acceleration time at the existing step transmission of ICE, when implementing the total traction force, boundary for the drive wheels adhesion to the road, and during implementation of the proposed rational law for acceleration control. To model ICE speed characteristics, we applied the empirical dependence by S.R. Leyderman. The analytical expressions obtained allow us to implement such a change in vehicle acceleration depending on its speed that makes it possible to ensure maximum dynamism at minimal engine power consumption, taking into consideration a nonlinear change in external resistance. The maximum acceleration, which is possible to implement using the rational dynamic characteristic, can reach 7 m/s2. Based on the dependences obtained, it is possible to determine effective work of ICE required to accelerate a vehicle at different gears. An analysis of calculation results revealed that the transition from lower to higher gears is accompanied by a sharp decrease in engine energy expenditure required to accelerate the vehicle.It was established that for the case of hybrid vehicles, acceleration using the electric drive, rather than accelerating at lower gears of the mechanical drive, makes it possible to reduce energy losses by 20 % (for a four-cylinder internal combustion engine). Energy preservation is accomplished by reducing the fluctuation of traction force, as well as the possibility of a step-free change in motion speed.Определена рациональная динамическая характеристика автомобиля, позволяющая разгон при минимальных затратах энергии двигателя. Определены законы изменения времени разгона автомобиля при реализации предельной по сцеплению ведущих колес с дорогой суммарной тяговой силы и при реализации предложенного рационального закона управления ускорением. Проведена оценка эффективной работы ДВС при разгоне на различных передачах автомобиляВизначена раціональна динамічна характеристика автомобіля, що дозволяє розгін при мінімальних витратах енергії двигуна. Визначено закони зміни часу розгону автомобіля при реалізації граничної по зчепленню ведучих коліс з дорогою сумарної тягової сили й при реалізації запропонованого раціонального закону управління прискоренням. Проведена оцінка ефективної роботи ДВЗ при розгоні на різних передачах автомобіл

    CRISPR/Cas9-induced modification of the conservative promoter region of VRN-A1 alters the heading time of hexaploid bread wheat

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    In cereals, the vernalization-related gene network plays an important role in regulating the transition from the vegetative to the reproductive phase to ensure optimal reproduction in a temperate climate. In hexaploid bread wheat (Triticum aestivum L.), the spring growth habit is associated with the presence of at least one dominant locus of VERNALIZATION 1 gene (VRN-1), which usually differs from recessive alleles due to mutations in the regulatory sequences of the promoter or/and the first intron. VRN-1 gene is a key regulator of floral initiation; various combinations of dominant and recessive alleles, especially VRN-A1 homeologs, determine the differences in the timing of wheat heading/flowering. In the present study, we attempt to expand the types of VRN-A1 alleles using CRISPR/Cas9 targeted modification of the promoter sequence. Several mono- and biallelic changes were achieved within the 125-117 bp upstream sequence of the start codon of the recessive vrn-A1 gene in plants of semi-winter cv. ‘Chinese Spring’. New mutations stably inherited in subsequent progenies and transgene-free homozygous plants carrying novel VRN-A1 variants were generated. Minor changes in the promoter sequence, such as 1–4 nucleotide insertions/deletions, had no effect on the heading time of plants, whereas the CRISPR/Cas9-mediated 8 bp deletion between −125 and −117 bp of the vrn-A1 promoter shortened the time of head emergence by up to 2-3 days. Such a growth habit was consistently observed in homozygous mutant plants under nonvernalized cultivation using different long day regimes (16, 18, or 22 h), whereas the cold treatment (from two weeks and more) completely leveled the effect of the 8 bp deletion. Importantly, comparison with wild-type plants showed that the implemented alteration has no negative effects on main yield characteristics. Our results demonstrate the potential to manipulate the heading time of wheat through targeted editing of the VRN-A1 gene promoter sequence on an otherwise unchanged genetic background

    Синтез енергоефективного закону управління розгоном автомобіля

    Get PDF
    We have established the laws of change in the vehicle acceleration time at the existing step transmission of ICE, when implementing the total traction force, boundary for the drive wheels adhesion to the road, and during implementation of the proposed rational law for acceleration control. To model ICE speed characteristics, we applied the empirical dependence by S.R. Leyderman. The analytical expressions obtained allow us to implement such a change in vehicle acceleration depending on its speed that makes it possible to ensure maximum dynamism at minimal engine power consumption, taking into consideration a nonlinear change in external resistance. The maximum acceleration, which is possible to implement using the rational dynamic characteristic, can reach 7 m/s2. Based on the dependences obtained, it is possible to determine effective work of ICE required to accelerate a vehicle at different gears. An analysis of calculation results revealed that the transition from lower to higher gears is accompanied by a sharp decrease in engine energy expenditure required to accelerate the vehicle.It was established that for the case of hybrid vehicles, acceleration using the electric drive, rather than accelerating at lower gears of the mechanical drive, makes it possible to reduce energy losses by 20 % (for a four-cylinder internal combustion engine). Energy preservation is accomplished by reducing the fluctuation of traction force, as well as the possibility of a step-free change in motion speed.Определена рациональная динамическая характеристика автомобиля, позволяющая разгон при минимальных затратах энергии двигателя. Определены законы изменения времени разгона автомобиля при реализации предельной по сцеплению ведущих колес с дорогой суммарной тяговой силы и при реализации предложенного рационального закона управления ускорением. Проведена оценка эффективной работы ДВС при разгоне на различных передачах автомобиляВизначена раціональна динамічна характеристика автомобіля, що дозволяє розгін при мінімальних витратах енергії двигуна. Визначено закони зміни часу розгону автомобіля при реалізації граничної по зчепленню ведучих коліс з дорогою сумарної тягової сили й при реалізації запропонованого раціонального закону управління прискоренням. Проведена оцінка ефективної роботи ДВЗ при розгоні на різних передачах автомобіл
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