1,285 research outputs found
Distinguished bases of exceptional modules
Exceptional modules are tree modules. A tree module usually has many tree
bases and the corresponding coefficient quivers may look quite differently. The
aim of this note is to introduce a class of exceptional modules which have a
distinguished tree basis, we call them radiation modules (generalizing an
inductive construction considered already by Kinser). For a Dynkin quiver,
nearly all indecomposable representations turn out to be radiation modules, the
only exception is the maximal indecomposable module in case E_8. Also, the
exceptional representation of the generalized Kronecker quivers are given by
radiation modules. Consequently, with the help of Schofield induction one can
display all the exceptional modules of an arbitrary quiver in a nice way.Comment: This is a revised and slightly expanded version. Propositions 1 and 2
have been corrected, some examples have been inserte
Psychodynamic Perspectives on Relationship: Implications of New Findings From Human Attachment and the Neurosciences for Social Work Education
In this article, the historical significance of the therapeutic relationship in social casework theory and practice is discussed and elaborated on in relation to contemporary psychodynamic theories and constructs, such as the therapeutic alliance, the holding relationship, and selfobject theory. The significant contributions of investigators in such diverse fields as infant attachment, neurobiology, and feminist theory are then discussed in relation to these psychoanalytic ideas. Based in part upon recent research being conducted in such fields, a more central role is proposed for psychodynamic conceptions of relationship in the education of social work clinicians
The double Ringel-Hall algebra on a hereditary abelian finitary length category
In this paper, we study the category of semi-stable
coherent sheaves of a fixed slope over a weighted projective curve. This
category has nice properties: it is a hereditary abelian finitary length
category. We will define the Ringel-Hall algebra of and
relate it to generalized Kac-Moody Lie algebras. Finally we obtain the Kac type
theorem to describe the indecomposable objects in this category, i.e. the
indecomposable semi-stable sheaves.Comment: 29 page
Better preparation and training determine home care workers’ self-efficacy in contributing to heart failure self-carebetter preparation
Objective
Identify determinants of home care workers’ (HCW) self-efficacy in contributing to heart failure (HF) self-care.
Methods
Secondary analysis of a survey (n = 328) examining characteristics of HCWs caring for adults with HF in New York. Self-efficacy assessed using Caregiver Self-Efficacy in Contributing to Self-Care Scale. Standardized scores range 0–100; ≥ 70 points indicate adequate self-efficacy. Characteristics determined by self-efficacy (low vs. adequate). Prevalence ratios with 95% confidence intervals (PR [95% CI]) were estimated using multivariable Poisson regression with robust standard errors.
Results
Home care workers with adequate self-efficacy had at least some prior HF training (55% vs. 17%, p < .001) and greater job satisfaction (90% vs. 77%, p = .003). Significant determinants for adequate self-efficacy were employment length (1.02 [1.00–1.03], p = .027), preparation for caregiving (3.10 [2.42–3.96], p < .001), and HF training (1.48 [1.20–1.84], p < .001).
Conclusion
Home care agencies and policy-makers can target caregiving preparation and HF training to improve HCWs’ confidence in caring for adult HF patients
Liouville coherent states
For a certain class of open quantum systems there exists a dynamical symmetry
which connects different time-evolved density matrices. We show how to use this
symmetry for dynamics in the Liouville space with time-dependent parameters.
This allows us to introduce a concept of generalized coherent states (e.g.
density matrices) in the Liouville space. Dynamics of this class of density
matrices is characterized by robustness with respect to any time-dependent
perturbations of the couplings. We study their dynamical context while focusing
on common physical situations corresponding to compact and non-compact
symmetries.Comment: 6 pages, 3 figures, accepted to EP
Exploring complex networks via topological embedding on surfaces
We demonstrate that graphs embedded on surfaces are a powerful and practical
tool to generate, characterize and simulate networks with a broad range of
properties. Remarkably, the study of topologically embedded graphs is
non-restrictive because any network can be embedded on a surface with
sufficiently high genus. The local properties of the network are affected by
the surface genus which, for example, produces significant changes in the
degree distribution and in the clustering coefficient. The global properties of
the graph are also strongly affected by the surface genus which is constraining
the degree of interwoveness, changing the scaling properties from
large-world-kind (small genus) to small- and ultra-small-world-kind (large
genus). Two elementary moves allow the exploration of all networks embeddable
on a given surface and naturally introduce a tool to develop a statistical
mechanics description. Within such a framework, we study the properties of
topologically-embedded graphs at high and low `temperatures' observing the
formation of increasingly regular structures by cooling the system. We show
that the cooling dynamics is strongly affected by the surface genus with the
manifestation of a glassy-like freezing transitions occurring when the amount
of topological disorder is low.Comment: 18 pages, 7 figure
Molecular basis of RNA polymerase III transcription repression by Maf1
RNA polymerase III (Pol III) transcribes short RNAs required for cell growth. Under stress conditions, the conserved protein Maf1 rapidly represses Pol III transcription. We report the crystal structure of Maf1 and cryo-electron microscopic structures of Pol III, an active Pol III-DNA-RNA complex, and a repressive Pol III-Maf1 complex. Binding of DNA and RNA causes ordering of the Pol III-specific subcomplex C82/34/31 that is required for transcription initiation. Maf1 binds the Pol III clamp and rearranges C82/34/31 at the rim of the active center cleft. This impairs recruitment of Pol III to a complex of promoter DNA with the initiation factors Brf1 and TBP and thus prevents closed complex formation. Maf1 does however not impair binding of a DNA-RNA scaffold and RNA synthesis. These results explain how Maf1 specifically represses transcription initiation from Pol III promoters and indicate that Maf1 also prevents reinitiation by binding Pol III during transcription elongation
LR characterization of chirotopes of finite planar families of pairwise disjoint convex bodies
We extend the classical LR characterization of chirotopes of finite planar
families of points to chirotopes of finite planar families of pairwise disjoint
convex bodies: a map \c{hi} on the set of 3-subsets of a finite set I is a
chirotope of finite planar families of pairwise disjoint convex bodies if and
only if for every 3-, 4-, and 5-subset J of I the restriction of \c{hi} to the
set of 3-subsets of J is a chirotope of finite planar families of pairwise
disjoint convex bodies. Our main tool is the polarity map, i.e., the map that
assigns to a convex body the set of lines missing its interior, from which we
derive the key notion of arrangements of double pseudolines, introduced for the
first time in this paper.Comment: 100 pages, 73 figures; accepted manuscript versio
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