291 research outputs found

    Radio Labelings of Distance Graphs

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    A radio kk-labeling of a connected graph GG is an assignment cc of non negative integers to the vertices of GG such that ∣c(x)−c(y)∣≥k+1−d(x,y),|c(x) - c(y)| \geq k+1 - d(x,y), for any two vertices xx and yy, x≠yx\ne y, where d(x,y)d(x,y) is the distance between xx and yy in GG. In this paper, we study radio labelings of distance graphs, i.e., graphs with the set Z\Z of integers as vertex set and in which two distinct vertices i,j∈Zi, j \in \Z are adjacent if and only if ∣i−j∣∈D|i - j| \in D.Comment: 14 page

    A unitary correlation operator method

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    The short range repulsion between nucleons is treated by a unitary correlation operator which shifts the nucleons away from each other whenever their uncorrelated positions are within the replusive core. By formulating the correlation as a transformation of the relative distance between particle pairs, general analytic expressions for the correlated wave functions and correlated operators are given. The decomposition of correlated operators into irreducible n-body operators is discussed. The one- and two-body-irreducible parts are worked out explicitly and the contribution of three-body correlations is estimated to check convergence. Ground state energies of nuclei up to mass number A=48 are calculated with a spin-isospin-dependent potential and single Slater determinants as uncorrelated states. They show that the deduced energy- and mass-number-independent correlated two-body Hamiltonian reproduces all "exact" many-body calculations surprisingly well.Comment: 43 pages, several postscript figures, uses 'epsfig.cls'. Submitted to Nucl. Phys. A. More information available at http://www.gsi.de/~fm

    Quantum Robots and Environments

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    Quantum robots and their interactions with environments of quantum systems are described and their study justified. A quantum robot is a mobile quantum system that includes a quantum computer and needed ancillary systems on board. Quantum robots carry out tasks whose goals include specified changes in the state of the environment or carrying out measurements on the environment. Each task is a sequence of alternating computation and action phases. Computation phase activities include determination of the action to be carried out in the next phase and possible recording of information on neighborhood environmental system states. Action phase activities include motion of the quantum robot and changes of neighborhood environment system states. Models of quantum robots and their interactions with environments are described using discrete space and time. To each task is associated a unitary step operator T that gives the single time step dynamics. T = T_{a}+T_{c} is a sum of action phase and computation phase step operators. Conditions that T_{a} and T_{c} should satisfy are given along with a description of the evolution as a sum over paths of completed phase input and output states. A simple example of a task carrying out a measurement on a very simple environment is analyzed. A decision tree for the task is presented and discussed in terms of sums over phase paths. One sees that no definite times or durations are associated with the phase steps in the tree and that the tree describes the successive phase steps in each path in the sum.Comment: 30 Latex pages, 3 Postscript figures, Minor mathematical corrections, accepted for publication, Phys Rev

    The Representation of Natural Numbers in Quantum Mechanics

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    This paper represents one approach to making explicit some of the assumptions and conditions implied in the widespread representation of numbers by composite quantum systems. Any nonempty set and associated operations is a set of natural numbers or a model of arithmetic if the set and operations satisfy the axioms of number theory or arithmetic. This work is limited to k-ary representations of length L and to the axioms for arithmetic modulo k^{L}. A model of the axioms is described based on states in and operators on an abstract L fold tensor product Hilbert space H^{arith}. Unitary maps of this space onto a physical parameter based product space H^{phy} are then described. Each of these maps makes states in H^{phy}, and the induced operators, a model of the axioms. Consequences of the existence of many of these maps are discussed along with the dependence of Grover's and Shor's Algorithms on these maps. The importance of the main physical requirement, that the basic arithmetic operations are efficiently implementable, is discussed. This conditions states that there exist physically realizable Hamiltonians that can implement the basic arithmetic operations and that the space-time and thermodynamic resources required are polynomial in L.Comment: Much rewrite, including response to comments. To Appear in Phys. Rev.

    A Quantum Anti-Zeno Paradox

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    We establish an exact differential equation for the operator describing time-dependent measurements continuous in time and obtain a series solution. Suppose the projection operator E(t)=U(t)EU†(t)E(t) = U(t) E U^\dagger(t) is measured continuously from t = 0 to T, where E is a projector leaving the initial state unchanged and U(t) a unitary operator obeying U(0) = 1 and some smoothness conditions in t. We prove that the probability of always finding E(t) = 1 from t = 0 to T is unity. If U(t)≠1U(t) \neq 1, the watched kettle is sure to `boil'.Comment: 10 pages,late

    Self awareness of the supervisor in supervision

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    Teaching self awareness is an important and sensitive task in the supervision of the clinical casework student. However, lack of self awareness on the part of the supervisor may lead to a serious impaction of this learning process, and unfortunately, there is no institutionalized process for reviewing lack of supervisory self awareness as there is for students. Some occasions in which problems in supervisory self awareness are likely to occur are: the supervisor who has difficulty in responding appropriately to the student's dependency demands in supervision, responding either by withdrawing from the student or being overprotective of him; the supervisor who is threatened by students whose character styles are very different from his own; and the supervisor who views client behavior from the perspective of a value system very different from the student's.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44357/1/10615_2004_Article_BF00760155.pd

    Utilizing Creativity for Adolescents’ Recovery in Inpatient Psychiatric Hospital (IPH)

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    The study aims to examine the impact of creative activities on adolescents, aged 12-18, hospitalized in an acute-care inpatient psychiatric hospital (IPH) setting. While research on the health impact of creative writing has been discussed with adults, research on adolescents hospitalized in acute inpatient psychiatric units (IPU) is limited. This study highlights how creative activities generate self-discovery and insights that are necessary for coping among adolescents in IPH. Seventy creative writing and origami sessions were embedded as a part of group education from March, 2018 until Feb. 2020. A curriculum that considered the interests of current teenagers and the IPH short length of stay (4-5 days) was designed and delivered by a professional writer and their team that consisted of health sciences students, medical students, and IPU nursing staff. After each session, a post-session survey was administered. The findings from 568 post-surveys suggest that the adolescents at the IPH expressed interest and engagement through creative activities. In addition, the findings suggest creative activities promote mood shifts, relaxation, and self-awareness, all critical for adolescents during a mental health crisis. Further studies are needed to assess if these activities lead to long-term coping strategies for participants following their hospitalization

    Sialylation of campylobacter jejuni lipo-oligosaccharides: impact on phagocytosis and cytokine production in mice

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    <p>Background: Guillain-Barré syndrome (GBS) is a post-infectious polyradiculoneuropathy, frequently associated with antecedent Campylobacter jejuni (C. jejuni) infection. The presence of sialic acid on C. jejuni lipo-oligosaccharide (LOS) is considered a risk factor for development of GBS as it crucially determines the structural homology between LOS and gangliosides, explaining the induction of cross-reactive neurotoxic antibodies. Sialylated C. jejuni are recognised by TLR4 and sialoadhesin; however, the functional implications of these interactions in vivo are unknown.</p> <p>Methodology/Principal Findings: In this study we investigated the effects of bacterial sialylation on phagocytosis and cytokine secretion by mouse myeloid cells in vitro and in vivo. Using fluorescently labelled GM1a/GD1a ganglioside-mimicking C. jejuni strains and corresponding (Cst-II-mutant) control strains lacking sialic acid, we show that sialylated C. jejuni was more efficiently phagocytosed in vitro by BM-MΦ, but not by BM-DC. In addition, LOS sialylation increased the production of IL-10, IL-6 and IFN-β by both BM-MΦ and BM-DC. Subsequent in vivo experiments revealed that sialylation augmented the deposition of fluorescent bacteria in splenic DC, but not macrophages. In addition, sialylation significantly amplified the production of type I interferons, which was independent of pDC.</p> <p>Conclusions/Significance: These results identify novel immune stimulatory effects of C. jejuni sialylation, which may be important in inducing cross-reactive humoral responses that cause GBS</p&gt

    A collaborative-interactive model for mental health consultation: Teacher inservice education by psychiatric clinicians

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    Primary prevention of emotional disorders is often cited as a goal in community mental health consultation. The daily contact with children and parents by the classroom teacher can yield effective prevention, if the teacher is appropriately prepared to act as a resource, and by clinicians given an awareness of emotional difficulties in children and their parents. Though consultation is often described as facilitative of change, typically discussions of such programs emphasize technique rather than content. Presented here is a collaborative model based upon a didactic input of humanistic psychology, upon which educator and clinician draw as they become allies in pursuit of answers to questions raised in current examples from the teacher's classroom experience. Excerpts and results of the model's effectiveness are given.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43964/1/10578_2005_Article_BF01433269.pd
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