Irregularity Measures of Graph

Abstract: Let G = (V, E), V = {1, 2, . . . , n}, be a simple graph without isolated vertices, with vertex degree sequence is measure of irregularity of graph G with the property I(G) = 0 if and only if G is regular, and I(G) > 0 otherwise. In this paper we introduce some new irregularity measures

Tunneling-driven breakdown of the 331 state and the emergent Pfaffian and composite Fermi liquid phases

We examine the possibility of creating the Moore-Read Pfaffian in the lowest Landau level when the multicomponent Halperin 331 state (believed to describe quantum Hall bilayers and wide quantum wells at the filling factor $\nu=1/2$) is destroyed by the increase of tunneling. Using exact diagonalization of the bilayer Hamiltonian with short-range and long-range (Coulomb) interactions in spherical and periodic rectangular geometries, we establish that tunneling is a perturbation that drives the 331 state into a compressible composite Fermi liquid, with the possibility for an intermediate critical state that possesses some properties of the Moore-Read Pfaffian. These results are interpreted in the two-component BCS model for Cauchy pairing with a tunneling constraint. We comment on the conditions to be imposed on a system with fluctuating density in order to achieve the stable Pfaffian phase.Comment: 10 pages, 7 figure

Manufacturing and integrity of ammonia storage tanks

Manufacturing ammonia storage tanks represents a very demanding and responsible task. The paper presents the methodology for manufacturing two ammonia storage tanks in Russia, along with all the necessary steps. The base material used for tank manufacture is steel P355NL2. Instructions and requirements in EN 14620 standard need to be followed. This standard dictates all previously mentioned steps, hence the standard itself is shown here. The welding technology of two steel tank shells is also shown. Integrity assessment of the tanks is necessary to carry out immediately before the tanks are put into service. NDT results for welded joints and results of adequate tests performed on the tanks themselves provided insight into the quality of the performed work, and have shown that the selected welding technologies have met all requirements in terms of strength, thus confirming that the tank integrity is satisfactory

Manufacturing and integrity of ammonia storage tanks

Manufacturing ammonia storage tanks represents a very demanding and responsible task. The paper presents the methodology for manufacturing two ammonia storage tanks in Russia, along with all the necessary steps. The base material used for tank manufacture is steel P355NL2. Instructions and requirements in EN 14620 standard need to be followed. This standard dictates all previously mentioned steps, hence the standard itself is shown here. The welding technology of two steel tank shells is also shown. Integrity assessment of the tanks is necessary to carry out immediately before the tanks are put into service. NDT results for welded joints and results of adequate tests performed on the tanks themselves provided insight into the quality of the performed work, and have shown that the selected welding technologies have met all requirements in terms of strength, thus confirming that the tank integrity is satisfactory

Fractional quantum Hall states with negative flux: edge modes in some Abelian and non-Abelian cases

We investigate the structure of gapless edge modes propagating at the boundary of some fractional quantum Hall states. We show how to deduce explicit trial wavefunctions from the knowledge of the effective theory governing the edge modes. In general quantum Hall states have many edge states. Here we discuss the case of fractions having only two such modes. The case of spin-polarized and spin-singlet states at filling fraction 2/5 is considered. We give an explicit description of the decoupled charged and neutral modes. Then we discuss the situation involving negative flux acting on the composite fermions. This happens notably for the filling factor 2/3 which supports two counterpropagating modes. Microscopic wavefunctions for spin-polarized and spin-singlet states at this filling factor are given. Finally we present an analysis of the edge structure of a non-Abelian state involving also negative flux. Counterpropagating modes involve in all cases explicit derivative operators diminishing the angular momentum of the system.Comment: 12 pages, entirely revised version, major conceptual change

Topological d-wave pairing structures in Jain states

We discuss d-wave topological (broken time reversal symmetry) pairing structures in unpolarized and polarized Jain states. We demonstrate pairing in the Jain spin singlet state by rewriting it in an explicit pairing form, in which we can recognize d-wave weak pairing of underlying quasiparticles - neutral fermions. We find and describe the root configuration of the Jain spin singlet state and its connection with neutral excitations of the Haldane-Rezayi state, and study the transition between these states via exact diagonalization. We find high overlaps with the Jain spin singlet state upon a departure from the hollow core model for which the Haldane-Rezayi state is the exact ground state. Due to a proven algebraic identity we were able to extend the analysis of topological d-wave pairing structures to polarized Jain states and integer quantum Hall states, and discuss its consequences.Comment: 8 page

Influence of the protein content of boar seminal plasma on spermatozoa viability, motility and acrosome integrity in diluted semen stored for 3 days

The aim of the present study was to investigate the influence of the protein content of seminal plasma on the motility, viability and acrosome integrity of spermatozoa in extended semen stored for 3 days. A total of 32 semen samples (from four boars) with high (4 mg/ml) and 32 semen samples (from four boars) with low (2 mg/ml) protein content were investigated. The semen samples were diluted by BTS at a ratio of 1:4, and stored for 72 h at 17oC. The percentages of live sperm (LS), live sperm with damaged acrosome (LDA) and total sperm with damaged acrosome (TDA) were detected by flow cytometry. Sperm progressive motility (PM) was detected using CASA. After 72 h of storage, the percentage of LS and PM was significantly (P lt 0.01) higher, and the LDA and TDA were significantly (P lt 0.01) lower in samples with high protein content than in the samples with low protein content (LS = 66 vs. 44%, PM = 64 vs. 48%, LDA = 15 vs. 21% and TDA = 29 vs. 45%, respectively). When comparing the difference between 0 and 72 h of storage, the percentage decrease in LS and PM, while increase in LDA and TDA were significantly higher in the samples with low (LS: 75 to 44%; PM: 68 to 48%; LDA: 11 to 21% and TDA: 23 to 45%) than in the samples with high protein content (LS: 78 to 66%; PM: 70 to 64%; LDA: 9 to 15% and TDA: 17 to 29%). We concluded that protein content in seminal plasma has a significant influence on progressive motility, viability and acrosome integrity in diluted semen stored for 3 days

Short-term liquid storage of ram semen in various extenders

The aim of this study was to investigate the effects of three extenders on ram sperm quality after short-term liquid storage (24 hours’ holding time). The study included 20 crossbred rams (Pirot Pramenka x Wurttemberg x Ile de France), 12 months old. Animals were housed at the experimental sheep farm of the Institute for Animal Husbandry in Belgrade, Serbia. Semen was collected through electro ejaculation. The ejaculates were obtained from single services and routine field analysis of the semen was performed immediately after the collection. The semen was split and diluted with three extenders, namely Optidyl®, Andromed® and ultrahigh temperature processed (UHT) milk, in ratios of 1 : 50 or 1 : 100. The ejaculates were examined for sperm motility variables (sperm cell motility percentage, the progressive motility percentage, curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), sperm linearity (LIN), straightness (STR), amplitude of lateral sperm head displacement (ALH), beat cross frequency (BCF) and circular tracks), and sperm morphology (live sperm percentage, percentage of normal sperm forms with intact acrosome, percentage of abnormal sperm forms and total damaged acrosome) by computer-assisted sperm analysis (CASA) and classic sperm cytology after supravital eosin/nigrosine/trypan blue staining, respectively. It was observed that the type of extender used in diluting ram semen is an important factor in the successful short-term liquid preservation (at 4 °C) of ram spermatozoa. In conclusion, this study showed that egg yolk (Optidyl) and soybean (Andromed)-based extenders gave better results of both sperm morphology and sperm motility parameters compared with UHT milk.Keywords: Diluents, morphology, motility, sper

Development of Grid e-Infrastructure in South-Eastern Europe

Over the period of 6 years and three phases, the SEE-GRID programme has established a strong regional human network in the area of distributed scientific computing and has set up a powerful regional Grid infrastructure. It attracted a number of user communities and applications from diverse fields from countries throughout the South-Eastern Europe. From the infrastructure point view, the first project phase has established a pilot Grid infrastructure with more than 20 resource centers in 11 countries. During the subsequent two phases of the project, the infrastructure has grown to currently 55 resource centers with more than 6600 CPUs and 750 TBs of disk storage, distributed in 16 participating countries. Inclusion of new resource centers to the existing infrastructure, as well as a support to new user communities, has demanded setup of regionally distributed core services, development of new monitoring and operational tools, and close collaboration of all partner institution in managing such a complex infrastructure. In this paper we give an overview of the development and current status of SEE-GRID regional infrastructure and describe its transition to the NGI-based Grid model in EGI, with the strong SEE regional collaboration.Comment: 22 pages, 12 figures, 4 table