743 research outputs found

    On free energies of the Ising model on the Cayley tree

    Full text link
    We present, for the Ising model on the Cayley tree, some explicit formulae of the free energies (and entropies) according to boundary conditions (b.c.). They include translation-invariant, periodic, Dobrushin-like b.c., as well as those corresponding to (recently discovered) weakly periodic Gibbs states. The later are defined through a partition of the tree that induces a 4-edge-coloring. We compute the density of each color.Comment: 18 pages, 4 figure

    Community Rehabilitation Programs and Organizational Change: A Mentor Guide to Increase Customized Employment Outcomes

    Get PDF
    [Excerpt] For the purpose of this Guide, customized employment is defined as a process for individualizing the employment relationship between an employee and an employer in ways that meet the needs of both. Customized employment is based on an individualized negotiation between the strengths, conditions and interests of the person with a disability and the identified business needs of the employer or the self-employment business chosen by the job seeker. Job negotiation uses job development or restructuring strategies that result in responsibilities being customized and individually negotiated to fit the requirements of the job

    On pp-adic Gibbs Measures for Hard Core Model on a Cayley Tree

    Full text link
    In this paper we consider a nearest-neighbor pp-adic hard core (HC) model, with fugacity λ\lambda, on a homogeneous Cayley tree of order kk (with k+1k + 1 neighbors). We focus on pp-adic Gibbs measures for the HC model, in particular on pp-adic "splitting" Gibbs measures generating a pp-adic Markov chain along each path on the tree. We show that the pp-adic HC model is completely different from real HC model: For a fixed kk we prove that the pp-adic HC model may have a splitting Gibbs measure only if pp divides 2k−12^k-1. Moreover if pp divides 2k−12^k-1 but does not divide k+2k+2 then there exists unique translational invariant pp-adic Gibbs measure. We also study pp-adic periodic splitting Gibbs measures and show that the above model admits only translational invariant and periodic with period two (chess-board) Gibbs measures. For p≥7p\geq 7 (resp. p=2,3,5p=2,3,5) we give necessary and sufficient (resp. necessary) conditions for the existence of a periodic pp-adic measure. For k=2 a pp-adic splitting Gibbs measures exists if and only if p=3, in this case we show that if λ\lambda belongs to a pp-adic ball of radius 1/27 then there are precisely two periodic (non translational invariant) pp-adic Gibbs measures. We prove that a pp-adic Gibbs measure is bounded if and only if p≠3p\ne 3.Comment: 17 page

    Thermodynamic versus Topological Phase Transitions: Cusp in the Kert\'esz Line

    Full text link
    We present a study of phase transitions of the Curie--Weiss Potts model at (inverse) temperature β\beta, in presence of an external field hh. Both thermodynamic and topological aspects of these transitions are considered. For the first aspect we complement previous results and give an explicit equation of the thermodynamic transition line in the β\beta--hh plane as well as the magnitude of the jump of the magnetization (for q⩾3)q \geqslant 3). The signature of the latter aspect is characterized here by the presence or not of a giant component in the clusters of a Fortuin--Kasteleyn type representation of the model. We give the equation of the Kert\'esz line separating (in the β\beta--hh plane) the two behaviours. As a result, we get that this line exhibits, as soon as q⩾3q \geqslant 3, a very interesting cusp where it separates from the thermodynamic transition line

    The Plant Ontology facilitates comparisons of plant development stages across species

    Get PDF
    The Plant Ontology (PO) is a community resource consisting of standardized terms, definitions, and logical relations describing plant structures and development stages, augmented by a large database of annotations from genomic and phenomic studies. This paper describes the structure of the ontology and the design principles we used in constructing PO terms for plant development stages. It also provides details of the methodology and rationale behind our revision and expansion of the PO to cover development stages for all plants, particularly the land plants (bryophytes through angiosperms). As a case study to illustrate the general approach, we examine variation in gene expression across embryo development stages in Arabidopsis and maize, demonstrating how the PO can be used to compare patterns of expression across stages and in developmentally different species. Although many genes appear to be active throughout embryo development, we identified a small set of uniquely expressed genes for each stage of embryo development and also between the two species. Evaluating the different sets of genes expressed during embryo development in Arabidopsis or maize may inform future studies of the divergent developmental pathways observed in monocotyledonous versus dicotyledonous species. The PO and its annotation databasemake plant data for any species more discoverable and accessible through common formats, thus providing support for applications in plant pathology, image analysis, and comparative development and evolution

    Gelatine based gel polymer electrolyte towards more sustainable Lithium-Oxygen batteries

    Get PDF
    The lithium-oxygen battery has attracted wide interest thanks to its very high theoretical energy density, and as such it is considered by many as a valid battery of the future candidate. However, the challenges in its practical application are many, such as liquid electrolyte evaporation in semi-open systems, as well as solvents instability in a highly oxidizing environment. In this work, we propose to use gelatin, from cold water fish skin, a waste from the fishing industry, to prepare an efficient gel electrolyte for future Li-O2 battery applications. After a single step methacrylation in water, methacrylated gelatine is directly cross-linked in presence of liquid electrolyte through UV- initiated radical polymerization. The obtained gel polymer electrolytes present good thermal and mechanical properties, good electrochemical stability against Li metal and ionic conductivities as high as 2.51 mS cm−1 at room temperature. the Li-O2 cells assembled with this bio-renewable gel polymer electrolytes were able to perform more than 100 cycles at 0.1 mA cm−2, under constant O2 flow, at room temperature and at a fixed capacity of 0.2 mAh cm−2. Cathodes post- mortem analysis confirmed that the cross-linked gelatin matrix was able to slow down solvent degradation and therefore enhance the cell reversibility

    52-56 A STUDY OF SELF-POLLINATION AND CROSS-POLLINATION IN AVOCADO (PERSEA AMERICANA MILL.) CV. HASS OF DIFFERENT VARIETIES

    Get PDF
    Abstract The following study was carried out al "La Palma!' Experimental Center of de Faculty of Agronomy of de Catholic University of Valparaiso, for the evaluation of the influence of different avocado varieties as pollinators of Hass. A Hass test field (planted l0xl0m.) was used, containing sections with different pollinators planted in 1975. Pollinators are distributed in quincunce in the Hass planting, belonging to the Bacon, Edranol, Hass, Rincon and Zutano varieties. The control was a section with only Hass trees planted without pollinators. The aim was to determine for each combination and the control the percentages of self-pollination and cross-pollination in the descendants of the Hass fruits by analyzing the origin of parental pollen in fruit embryos using isoenzymes as genetic markers; thereby enabling a determination of which varieties behave better as pollinators of Hass under local conditions in the Quillota area. Electrophoresis test in starch gels at 11% concentrations were carried out using 14 isoenzymatic systems of GOT-1, GOT-2, PGI-2, PGM-1, PGM-2, LAP-1, LAP-2, EST-FL, MDIL TPI-2, SKDH-1, SKDH-2, 6-PGD-2, 6-PGD-3 and 6-PGD-4. The analyzed fruit was collected from October 1994 to January 1995. The results showed Hass to be weak self-pollinator, being easily displaced by pollen from other parental plant when found associated to other varieties. The pollinators which provided the highest cross-pollination results in their combinations were Zutano, Edranol and Bacon cultivars, presenting no significant differences between them. Rincon variety proved a weak pollinator for Hass

    Monocot fossils suitable for molecular dating analyses

    Full text link
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111920/1/boj12233.pd
    • …
    corecore