13,179 research outputs found
Universality of collapsing two-dimensional self-avoiding trails
Results of a numerically exact transfer matrix calculation for the model of
Interacting Self-Avoiding Trails are presented. The results lead to the
conclusion that, at the collapse transition, Self-Avoiding Trails are in the
same universality class as the O(n=0) model of Blote and Nienhuis (or
vertex-interacting self-avoiding walk), which has thermal exponent ,
contrary to previous conjectures.Comment: Final version, accepted for publication in Journal of Physics A; 9
pages; 3 figure
Examining c-di-GMP and possible quorum sensing regulation in Pseudomonas fluorescens SBW25:links between intra and inter-cellular regulation benefits community cooperative activities such as biofilm formation
Bacterial success in colonizing complex environments requires individual response to micro-scale conditions as well as community-level cooperation to produce large-scale structures such as biofilms. Connecting individual and community responses could be achieved by linking the intracellular sensory and regulatory systems mediated by bis-(3β²-5β²)-cyclic dimeric guanosine monophosphate (c-di-GMP) and other compounds of individuals with intercellular quorum sensing (QS) regulation controlling populations. There is growing evidence to suggest that biofilm formation by many pseudomonads is regulated by both intra and intercellular systems, though in the case of the model Pseudomonas fluorescens SBW25 Wrinkly Spreader in which mutations increasing c-di-GMP levels result in the production of a robust cellulose-based air-liquid interface biofilm, no evidence for the involvement of QS regulation has been reported. However, our recent review of the P. fluorescens SBW25 genome has identified a potential QS regulatory pathway and other QSβassociated genes linked to c-di-GMP homeostasis, and QS signal molecules have also been identified in culture supernatants. These findings suggest a possible link between c-di-GMP and QS regulation in P. fluorescens SBW25 which might allow a more sophisticated and responsive control of cellulose production and biofilm formation when colonising the soil and plant-associated environments P. fluorescens SBW25 normally inhabits.ΠΠ½Π°Π»ΠΈΠ· Ρ-Π΄ΠΈ-ΠΠΠ€ ΠΈ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΠ³ΠΎ ΡΡΠ²ΡΡΠ²Π° ΠΊΠ²ΠΎΡΡΠΌΠ° Ρ Pseudomonas fluorescens SBW 25: ΡΠ²ΡΠ·Ρ ΠΌΠ΅ΠΆΠ΄Ρ Π²Π½ΡΡΡΠΈ ΠΈ ΠΌΠ΅ΠΆΠΊΠ»Π΅ΡΠΎΡΠ½ΠΎΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΈΠ΅ΠΉ ΡΠΏΠΎΡΠΎΠ±ΡΡΠ²ΡΠ΅Ρ ΠΊΠΎΠΎΠΏΠ΅ΡΠ°ΡΠΈΠ²Π½ΠΎΠΌΡ ΠΏΠΎΠ²Π΅Π΄Π΅Π½ΠΈΡ Π² ΡΠΎΠΎΠ±ΡΠ΅ΡΡΠ²Π΅ ΠΈ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ Π±ΠΈΠΎΠΏΠ»ΡΠ½ΠΊΠΈΠ£ΡΠΏΠ΅ΡΠ½ΠΎΡΡΡ Π±Π°ΠΊΡΠ΅ΡΠΈΠ°Π»ΡΠ½ΠΎΠΉ ΠΊΠΎΠ»ΠΎΠ½ΠΈΠ·Π°ΡΠΈΠΈ ΡΠ»ΠΎΠΆΠ½ΡΡ
ΡΠΊΠΎΠ½ΠΈΡ ΡΡΠ΅Π±ΡΠ΅Ρ ΠΈΠ½Π΄ΠΈΠ²ΠΈΠ΄ΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΠΎΡΠ²Π΅ΡΠ° Π½Π° ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΡΡΠ»ΠΎΠ²ΠΈΠΉ Π½Π° ΠΌΠΈΠΊΡΠΎΡΡΠΎΠ²Π½Π΅ ΡΠ°Π²Π½ΠΎ ΠΊΠ°ΠΊ ΠΈ ΠΊΠΎΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΈ Π½Π° ΡΡΠΎΠ²Π½Π΅ ΡΠΎΠΎΠ±ΡΠ΅ΡΡΠ²Π° Π΄Π»Ρ ΠΏΡΠΎΠ΄ΡΠΊΡΠΈΠΈ ΡΠ°ΠΊΠΈΡ
ΠΊΡΡΠΏΠ½ΠΎ ΠΌΠ°ΡΡΡΠ°Π±Π½ΡΡ
ΡΡΡΡΠΊΡΡΡ ΠΊΠ°ΠΊ Π±ΠΈΠΎΠΏΠ»ΡΠ½ΠΊΠΈ. ΠΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΠΈΡ ΠΈΠ½Π΄ΠΈΠ²ΠΈΠ΄ΡΠ°Π»ΡΠ½ΡΡ
ΠΎΡΠ²Π΅Ρ ΠΎΠ² ΠΈ ΠΎΡΠ²Π΅ΡΠΎΠ² ΡΠΎΠΎΠ±ΡΠ΅ΡΡΠ²Π° ΠΌΠΎΠΆΠ΅Ρ Π±ΡΡΡ Π΄ΠΎΡΡΠΈΠ³Π½ΡΡΠ° ΠΏΡΡΠ΅ΠΌ ΡΠ²ΡΠ·ΡΠ²Π°Π½ΠΈΡ Π²Π½ΡΡΡΠΈΠΊΠ»Π΅ΡΠΎΡΠ½ΡΡ
ΡΠ΅Π½ΡΠΎΡΠ½ΡΡ
ΠΈ ΡΠ΅Π³ΡΠ»ΡΡΠΎΡΠ½ΡΡ
ΡΠΈΡΡΠ΅ΠΌ, ΠΎΠΏΠΎΡΡΠ΅Π΄ΡΠ΅ΠΌΡΡ
Π±ΠΈΡ-(3',5')-ΡΠΈΠΊΠ»ΠΈΡΠ΅ΡΠΊΠΈΠΌ Π΄ΠΈΠΌΠ΅ΡΠ½ΡΠΌ Π³ΡΠ°Π½ΠΎΠ·ΠΈΠ½ΠΌΠΎΠ½ΠΎΡΠΎΡΡΠ°ΡΠΎΠΌ (Ρ-Π΄ΠΈ-ΠΠΠ€) ΠΈ Π΄ΡΡΠ³ΠΈΠΌΠΈ ΡΠΎΠ΅Π΄ΠΈΠ½Π΅Π½ΠΈΡΠΌΠΈ ΠΈΠ½Π΄ΠΈΠ²ΠΈΠ΄ΡΡΠΌΠΎΠ² Ρ ΠΌΠ΅ΠΆΠΊΠ»Π΅ΡΠΎΡΠ½ΠΎΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΈΠ΅ΠΉ - ΡΡΠ²ΡΡΠ²ΠΎΠΌ ΠΊΠ²ΠΎΡΡΠΌΠ° (Π§Π), ΠΊΠΎΠ½ΡΡΠΎΠ»ΠΈΡΡΡΡΠ΅ΠΌ ΠΏΠΎΠΏΡΠ»ΡΡΠΈ Ρ. ΠΠ°ΠΊΠ°ΠΏΠ»ΠΈΠ²Π°Π΅ΡΡΡ Π²ΡΡ Π±ΠΎΠ»ΡΡΠ΅ Π΄ΠΎΠΊΠ°Π·Π°ΡΠ΅Π»ΡΡΡΠ² ΡΠΎΠ³ΠΎ, ΡΡΠΎ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ Π±ΠΈΠΎΠΏΠ»Π΅Π½ΠΊΠΈ ΠΌΠ½ΠΎΠ³ΠΈΠΌΠΈ ΠΏΡΠ΅Π²Π΄ΠΎΠΌΠΎΠ½Π°Π΄Π°ΠΌΠΈ ΡΠ΅Π³ΡΠ»ΠΈΡΡΠ΅ΡΡΡ ΠΊΠ°ΠΊ Π²Π½ΡΡΡΠΈ ΠΊΠ»Π΅ΡΠΎΡΠ½ΡΠΌΠΈ, ΡΠ°ΠΊ ΠΈ ΠΌΠ΅ΠΆ ΠΊΠ»Π΅ΡΠΎΡΠ½ΡΠΌΠΈ ΡΠ΅Π³ΡΠ»ΡΡΠΎΡΠ½ΡΠΌΠΈ ΡΠΈΡΡΠ΅ΠΌΠ°ΠΌΠΈ, Ρ
ΠΎΡΡ Π² ΡΠ»ΡΡΠ°Π΅ ΠΌΠΎΠ΄Π΅Π»ΡΠ½ΠΎΠΉ Pseudomonas fluorescens SBW25 Wrinkly Spreader, Ρ ΠΊΠΎΡΠΎΡΠΎΠΉ ΠΌΡΡΠ°ΡΠΈΠΈ, ΠΏΠΎΠ²ΡΡΠ°ΡΡ ΠΈΠ΅ ΡΡΠΎΠ²Π½ΠΈ Ρ-Π΄ΠΈ-ΠΠΠ€, ΠΏΡΠΈΠ²ΠΎΠ΄ΡΡ ΠΊ ΡΠΎΠ·Π΄Π°Π½ΠΈΡ ΠΏΡΠΎΡΠ½ΠΎΠΉ ΡΠ΅Π»Π»ΡΠ»ΠΎΠ·Π½ΠΎΠΉ Π±ΠΈΠΎΠΏΠ»ΡΠ½ΠΊΠΈ Π½Π° Π³ΡΠ°Π½ΠΈΡΠ΅ ΡΠ°Π·Π΄Π΅Π»Π° ΡΠ°Π· Π²ΠΎΠ·Π΄ΡΡ
-ΠΆΠΈΠ΄ΠΊΠΎΡΡΡ, Π½Π΅ Π±ΡΠ»ΠΎ ΠΎΠ±Π½Π°ΡΡΠΆΠ΅Π½ΠΎ Π½ΠΈ ΠΊΠ° ΠΊΠΎΠ³ΠΎ ΡΠ²ΠΈΠ΄Π΅ΡΠ΅Π»ΡΡΡΠ²Π° Π²ΠΎΠ²Π»Π΅ΡΠ΅Π½ΠΈΡ ΠΊΠ²ΠΎΡΡΠΌ-Π·Π°Π²ΠΈΡΠΈΠΌΠΎΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΈΠΈ. ΠΠ΄Π½Π°ΠΊΠΎ Π½Π°Ρ Π½Π΅Π΄Π°Π²Π½ΠΈΠΉ ΠΎΠ±Π·ΠΎΡ Π³Π΅Π½ΠΎΠΌΠ° P. fluorescens SBW25 Π²ΡΡΠ²ΠΈΠ» ΠΏΠΎΡΠ΅Π½ΡΠΈΠ°Π»ΡΠ½ΡΠΉ Π§Π-Π·Π°Π²ΠΈΡΠΈΠΌΡΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΎΡΠ½ΡΠΉ ΠΏΡ ΡΡ ΠΈ Π΄ΡΡΠ³ΠΈΠ΅ Π§Π-Π·Π°Π²ΠΈΡΠΈΠΌΡΠ΅ Π³Π΅Π½Ρ, ΡΠ²ΡΠ·Π°Π½Π½ΡΠ΅ Ρ Π³ΠΎΠΌΠ΅ΠΎΡΡΠ°Π·ΠΎΠΌ Ρ-Π΄ΠΈ-ΠΠΠ€, Π° ΠΌΠΎΠ»Π΅ΠΊΡΠ»Ρ Π§Π-ΡΠΈΠ³Π½Π°Π»ΠΈΠ½Π³Π° Π±ΡΠ»ΠΈ ΠΈΠ΄Π΅Π½ΡΠΈΡΠΈΡΠΈΡΠΎΠ²Π°Π½Ρ Π² ΠΊΡΠ»ΡΡΡΡΠ΅. ΠΡΠΈ Π΄Π°Π½Π½ΡΠ΅ ΡΠ²ΠΈΠ΄Π΅ΡΠ΅Π»ΡΡΡΠ²ΡΡΡ ΠΎ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΠΉ ΡΠ²ΡΠ·ΠΈ ΠΌΠ΅ΠΆΠ΄Ρ Ρ-Π΄ΠΈ-ΠΠΠ€-ΡΠ΅Π³ΡΠ»ΡΡΠΈΠ΅ΠΉ ΠΈ Π§Π Ρ P. fluorescens SBW25, ΡΡΠΎ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ Π±ΠΎΠ»Π΅Π΅ ΡΠ»ΠΎΠΆΠ½ΡΠΉ ΠΈ Π³ΠΈΠ±ΠΊΠΈΠΉ ΠΊΠΎΠ½ΡΡΠΎΠ»Ρ Π½Π°Π΄ ΠΏΡΠΎΠ΄ΡΠΊΡΠΈΠ΅ΠΉ ΡΠ΅Π»Π»ΡΠ»ΠΎΠ·Ρ ΠΈ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈ Π΅ΠΌ Π±ΠΈΠΎΠΏΠ»Π΅Π½ΠΊΠΈ ΠΏΡΠΈ ΠΊΠΎΠ»ΠΎΠ½ΠΈΠ·Π°ΡΠΈΠΈ ΠΏΠΎΡΠ² ΠΈ ΡΠΊΠΎΠ½ΠΈΡ, aΡΡΠΎΡΠΈΠΈΡΠΎΠ²Π°Π½Π½ΡΡ
Ρ ΡΠ°ΡΡΠ΅Π½ΠΈΡΠΌ ΠΈ, - Π΅ΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΡΠΌΠΈ ΡΡΠ΅Π΄Π°ΠΌΠΈ ΠΎΠ±ΠΈΡΠ°Π½ΠΈΡ P. fluorescens SBW25
First-principles study of adsorption, diffusion, and charge stability of metal adatoms on alkali halide surfaces
In this work we have performed first-principles calculations based on the spin-polarized density-functional theory for the adsorption and diffusion of Au, Ag, and Pb atoms on NaCl(001), KCl(001), and KBr(001) surfaces. We consider also the influence of adatom charge on the adsorption and diffusion. In order to characterize the different systems we explicitly calculate charge transfer between surface and adatom and consider the relative stability of the various charge states. Our results show that in general, apart from positively charged systems, the adatoms are weakly bound to the surface via orbital polarization and ionic interactions, and relatively little charge transfer occurs. Au and Ag adatoms are highly mobile on all surfaces, although they can be pinned by removal of an electron. In contrast, Pb adatoms are fairly immobile, and their mobility increases upon charging. Analysis of the charge stability suggests that Ag offers the potential of charge controlled mobility on insulators.Peer reviewe
Defining the qualitative elements of Aichi Biodiversity Target 11 with regard to the marine and coastal environment in order to strengthen global efforts for marine biodiversity conservation outlined in the United Nations Sustainable Development Goal 14
The Convention on Biological Diversity (CBD) Aichi Target 11 states that, βby 2020, at least 17 per cent of terrestrial and inland water, and 10 per cent of coastal and marine areas, especially areas of particular importance for biodiversity and ecosystem services, are conserved through effectively and equitably managed, ecologically representative and well-connected systems of protected areas and other effective area-based conservation measures, and integrated into the wider landscapes and seascapesβ. There has been rapid progress to meet the quantitative goal (the 10% target). However, the qualitative aspects of Aichi target 11 are less well described. The United Nations Sustainable Development Goal (SDG) 14 to βconserve and sustainably use the oceans, seas and marine resources for sustainable developmentβ reaffirms the quantitative element of Aichi target 11, and, through the described sub-targets, places further emphasis on the economic and social context of global development. The complexity of the language from Aichi target 11 is not mirrored in SDG 14, leading to a potential scenario where the knowledge and progress towards Aichi Target 11 will be diluted as the focus shifts to the SDGs. This paper presents current knowledge and implementation of the qualitative elements of Aichi Target 11 and highlights gaps in knowledge. We conclude that the progress made so far on describing and implementing the qualitative goals of Aichi Target 11 should be integrated into SDG 14 in order to strengthen global efforts for marine biodiversity conservation and support the broader vision for sustainable development that will βtransform our worldβ
String amplitudes in arbitrary dimensions
We calculate gravitational dressed tachyon correlators in non critcal
dimensions. The 2D gravity part of our theory is constrained to constant
curvature. Then scaling dimensions of gravitational dressed vertex operators
are equal to their bare conformal dimensions. Considering the model as d+2
dimensional critical string we calculate poles of generalized Shapiro-Virasoro
amplitudes.Comment: 14 page
Magnetic properties of vacancies in graphene and single-walled carbon nanotubes
Spin-polarized density functional theory has been used to study the properties of vacancies in a graphene sheet and in single-walled carbon nanotubes (SWNTs). For graphene, we find that the vacancies are magnetic and the symmetry of the sheet is broken by the distortion of an atom next to the vacancy site. We also studied vacancies in four armchair SWNTs from (3,3) to (6,6) and six zigzag SWNTs from (5,0) to (10,0). Our calculations demonstrate that vacancies can change the electronic structure of SWNTs, converting some metallic nanotubes to semiconductors and vice versa. Metallic nanotubes with vacancies exhibit ferro- or ferrimagnetism, whereas some semiconducting nanotubes with vacancies show an antiferromagnetic order. The magnetic properties depend on chiralities of the tubes, the configuration of the vacancy and the concentration of the vacancies.Peer reviewe
Hydrogen-induced magnetism in carbon nanotubes
Spin-polarized density functional theory is used to investigate hydrogen-induced magnetism in single-walled carbon nanotubes (SWNTs). Hydrogen trapped at a carbon vacancy can trigger delocalized Ο electron spin polarization on semiconducting zigzag SWNTs. Hydrogen pinned by a carbon adatom on the surface of the SWNT can induce spin polarization localized at the carbon adatom, independent of the diameter and chirality of the tube.Peer reviewe
Properties of nonaqueous electrolytes Sixth summary report, 20 Sep. 1967 - 19 Mar. 1968
Physical properties and structural studies on propylene carbonate, dimethyl formamide, and acetonitrile solvent electrolyte
Surface critical behaviour of the Interacting Self-Avoiding Trail on the square lattice
The surface critical behaviour of the interacting self-avoiding trail is
examined using transfer matrix methods coupled with finite-size scaling.
Particular attention is paid to the critical exponents at the ordinary and
special points along the collapse transition line. The phase diagram is also
presented.Comment: Journal of Physics A (accepted
New Evidence for Efficient Collisionless Heating of Electrons at the Reverse Shock of a Young Supernova Remnant
Although collisionless shocks are ubiquitous in astrophysics, certain key
aspects of them are not well understood. In particular, the process known as
collisionless electron heating, whereby electrons are rapidly energized at the
shock front, is one of the main open issues in shock physics. Here we present
the first clear evidence for efficient collisionless electron heating at the
reverse shock of Tycho's supernova remnant (SNR), revealed by Fe-K diagnostics
using high-quality X-ray data obtained by the Suzaku satellite. We detect
K-beta (3p->1s) fluorescence emission from low-ionization Fe ejecta excited by
energetic thermal electrons at the reverse shock front, which peaks at a
smaller radius than Fe K-alpha (2p->1s) emission dominated by a relatively
highly-ionized component. Comparison with our hydrodynamical simulations
implies instantaneous electron heating to a temperature 1000 times higher than
expected from Coulomb collisions alone. The unique environment of the reverse
shock, which is propagating with a high Mach number into rarefied ejecta with a
low magnetic field strength, puts strong constraints on the physical mechanism
responsible for this heating, and favors a cross-shock potential created by
charge deflection at the shock front. Our sensitive observation also reveals
that the reverse shock radius of this SNR is about 10% smaller than the
previous measurement using the Fe K-alpha morphology from the Chandra
observations. Since strong Fe K-beta fluorescence is expected only from
low-ionization plasma where Fe ions still have many 3p electrons, this feature
is key to diagnosing the plasma state and distribution of the immediate
postshock ejecta in a young SNR.Comment: 7 pages, 9 figures, resubmitted to ApJ with minor changes following
the referee repor
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