3,041 research outputs found

    Relaxation dynamics of the Lieb-Liniger gas following an interaction quench: A coordinate Bethe-ansatz analysis

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    We investigate the relaxation dynamics of the integrable Lieb-Liniger model of contact-interacting bosons in one dimension following a sudden quench of the collisional interaction strength. The system is initially prepared in its noninteracting ground state and the interaction strength is then abruptly switched to a positive value, corresponding to repulsive interactions between the bosons. We calculate equal-time correlation functions of the nonequilibrium Bose field for small systems of up to five particles via symbolic evaluation of coordinate Bethe-ansatz expressions for operator matrix elements between Lieb-Liniger eigenstates. We characterize the relaxation of the system by comparing the time-evolving correlation functions following the quench to the equilibrium correlations predicted by the diagonal ensemble and relate the behavior of these correlations to that of the quantum fidelity between the many-body wave function and the initial state of the system. Our results for the asymptotic scaling of local second-order correlations with increasing interaction strength agree with the predictions of recent generalized thermodynamic Bethe-ansatz calculations. By contrast, third-order correlations obtained within our approach exhibit a markedly different power-law dependence on the interaction strength as the Tonks-Girardeau limit of infinitely strong interactions is approached.Comment: 19 pages, 10 figures. v3: Final version. Typos fixed, and other minor change

    Overriding Mental Health Treatment Refusals: How Much Process is “Due”?

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    Getting mental health treatment to patients who need it is today a much belegaled enterprise. This is in part because lawmakers have a skewed view of the enterprise, in particular regarding the treatment of patients with antipsychotic medications. The properties and uses of these medications are misunderstood by many in the legal community, with the drugs’ undesirable side effects typically overstated and the remedial effects undersold when not outright ignored. One specific legal effect has been to accord to mental patients a substantively outsized right to refuse treatment that comes with a correspondingly action-stifling dose of procedural safeguards, this despite the patients’ frequent lack of capacity to exercise the right wisely and the bad personal and systemic consequences that flow from that. The purpose of this Article is to provide better balanced and accurate evidence of the properties of antipsychotic drugs so as to convince lawmakers and advocates for the mentally disabled that it is safe to roll back some of the more counterproductive legal strictures on the effort to provide mental health treatment. An analysis of selected cases and statutes is intended to illustrate that such a roll back can and should be applied to a variety of legal and institutional contexts

    Inverting Ray-Knight identity

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    We provide a short proof of the Ray-Knight second generalized Theorem, using a martingale which can be seen (on the positive quadrant) as the Radon-Nikodym derivative of the reversed vertex-reinforced jump process measure with respect to the Markov jump process with the same conductances. Next we show that a variant of this process provides an inversion of that Ray-Knight identity. We give a similar result for the Ray-Knight first generalized Theorem.Comment: 18 page

    Assessment in Practice: A Companion Guide to the ASK Standards

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    Colleges today are asked to provide greater proof that they are providing quality educational experiences to their students. There has been a growing need for student affairs to provide documentation that their areas also impact learning and student experience. However, many student affairs professionals are overwhelmed by the idea of assessment and are looking for examples of best practices in this area. Several years ago the American College Personnel Association\u27s Commission Director for Assessment and Evaluation developed the Assessment Skills and Knowledge Standards for practitioners. This document provides exampes of these standards in practice

    Coupling GIS and LCA for biodiversity assessments of land use

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    Geospatial details about land use are necessary to assess its potential impacts on biodiversity. Geographic information systems (GIS) are adept at modeling land use in a spatially explicit manner, while life cycle assessment (LCA) does not conventionally utilize geospatial information. This study presents a proof-of-concept approach for coupling GIS and LCA for biodiversity assessments of land use and applies it to a case study of ethanol production from agricultural crops in California. GIS modeling was used to generate crop production scenarios for corn and sugar beets that met a range of ethanol production targets. The selected study area was a four-county region in the southern San Joaquin Valley of California, USA. The resulting land use maps were translated into maps of habitat types. From these maps, vectors were created that contained the total areas for each habitat type in the study region. These habitat compositions are treated as elementary input flows and used to calculate different biodiversity impact indicators in a second paper (Geyer et al., submitted). Ten ethanol production scenarios were developed with GIS modeling. Current land use is added as baseline scenario. The parcels selected for corn and sugar beet production were generally in different locations. Moreover, corn and sugar beets are classified as different habitat types. Consequently, the scenarios differed in both the habitat types converted and in the habitat types expanded. Importantly, land use increased nonlinearly with increasing ethanol production targets. The GIS modeling for this study used spatial data that are commonly available in most developed countries and only required functions that are provided in virtually any commercial or open-source GIS software package. This study has demonstrated that GIS-based inventory modeling of land use allows important refinements in LCA theory and practice. Using GIS, land use can be modeled as a geospatial and nonlinear function of output. For each spatially explicit process, land use can be expressed within the conventional structure of LCA methodology as a set of elementary input flows of habitat types

    Functional electrical stimulation cycling exercise after spinal cord injury: a systematic review of health and fitness-related outcomes.

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    ObjectivesThe objective of this review was to summarize and appraise evidence on functional electrical stimulation (FES) cycling exercise after spinal cord injury (SCI), in order to inform the development of evidence-based clinical practice guidelines.MethodsPubMed, the Cochrane Central Register of Controlled Trials, EMBASE, SPORTDiscus, and CINAHL were searched up to April 2021 to identify FES cycling exercise intervention studies including adults with SCI. In order to capture the widest array of evidence available, any outcome measure employed in such studies was considered eligible. Two independent reviewers conducted study eligibility screening, data extraction, and quality appraisal using Cochranes' Risk of Bias or Downs and Black tools. Each study was designated as a Level 1, 2, 3 or 4 study, dependent on study design and quality appraisal scores. The certainty of the evidence for each outcome was assessed using GRADE ratings ('High', 'Moderate', 'Low', or 'Very low').ResultsNinety-two studies met the eligibility criteria, comprising 999 adults with SCI representing all age, sex, time since injury, lesion level and lesion completeness strata. For muscle health (e.g., muscle mass, fiber type composition), significant improvements were found in 3 out of 4 Level 1-2 studies, and 27 out of 32 Level 3-4 studies (GRADE rating: 'High'). Although lacking Level 1-2 studies, significant improvements were also found in nearly all of 35 Level 3-4 studies on power output and aerobic fitness (e.g., peak power and oxygen uptake during an FES cycling test) (GRADE ratings: 'Low').ConclusionCurrent evidence indicates that FES cycling exercise improves lower-body muscle health of adults with SCI, and may increase power output and aerobic fitness. The evidence summarized and appraised in this review can inform the development of the first international, evidence-based clinical practice guidelines for the use of FES cycling exercise in clinical and community settings of adults with SCI. Registration review protocol: CRD42018108940 (PROSPERO)

    Online multifactorial prevention programme has no effect on the number of running-related injuries: a randomised controlled trial

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    Objective To examine the effect of a multifactorial, online injury prevention programme on the number of running-related injuries (RRIs) in recreational runners. Methods Adult recreational runners who registered for a runnin
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