Final surgical interventions in primary total knee arthroplasty infections : a retrospective

Poster presented at the 2017 Health Sciences Research Day which was organized and sponsored by the University of Missouri School of Medicine Research Council and held on November 9, 2017.Conclusions: Two stage revision is largely regard as the gold standard for treatment of chronic PJI in primary TKA. Follow-up for these patients who continue to be at risk for infection related failure over an extended period of time frequently did not return to the institution where their infection management was started. Our retrospective study identified that subset (23.8%) of those undergoing two-stage intervention and who had returned for follow-up were never reimplanted. Only half of those reimplanted retain those components over a 31 month follow up from the time of their initial intervention. These results give a more guarded prognosis for the outcome of patients with prosthetic joint replacement than what has been traditionally reported in the literature. The more challenging prognosis may be impacted by host comorbidities, antibiotic susceptibility of infecting organisms, timing to surgical treatment, or other factors

Scattering a pulse from a chaotic cavity: Transitioning from algebraic to exponential decay

The ensemble averaged power scattered in and out of lossless chaotic cavities decays as a power law in time for large times. In the case of a pulse with a finite duration, the power scattered from a single realization of a cavity closely tracks the power law ensemble decay initially, but eventually transitions to an exponential decay. In this paper, we explore the nature of this transition in the case of coupling to a single port. We find that for a given pulse shape, the properties of the transition are universal if time is properly normalized. We define the crossover time to be the time at which the deviations from the mean of the reflected power in individual realizations become comparable to the mean reflected power. We demonstrate numerically that, for randomly chosen cavity realizations and given pulse shapes, the probability distribution function of reflected power depends only on time, normalized to this crossover time.Comment: 23 pages, 5 figure

AART-BC: a sensor system for monitoring Assistive Technology use beyond the clinic

A wide range of assistive and rehabilitative technologies (ART) are available to assist with mobility and upper limb function. However, anecdotal evidence suggests many of the devices prescribed, or purchased, are either poorly used, or rejected entirely. This situation is costly, both for the healthcare provider and the user, and may be leading to secondary consequences, such as falls and/or social isolation. This paper reports on the development and initial feasibility testing of a system for monitoring when and how assistive devices are used outside of the clinic setting, and feeding this information to the device user themselves and/or prescribing clinician (where appropriate). Illustrative data from multiple time-synchronized device and body worn sensors are presented on a wheelchair user and a user of a “rollator” walking frame, moving along a walkway. Observation of the sensor data in both cases showed characteristic signatures corresponding to individual “pushes”. In parallel with this work, other project partners are exploring clinician and patient data requirements, as well we sensor set acceptability The initial results highlight the potential for the approach and demonstrate the need for further work to reduce and optimize the sensor set

The SKA Particle Array Prototype: The First Particle Detector at the Murchison Radio-astronomy Observatory

We report on the design, deployment, and first results from a scintillation detector deployed at the Murchison Radio-astronomy Observatory (MRO). The detector is a prototype for a larger array -- the Square Kilometre Array Particle Array (SKAPA) -- planned to allow the radio-detection of cosmic rays with the Murchison Widefield Array and the low-frequency component of the Square Kilometre Array. The prototype design has been driven by stringent limits on radio emissions at the MRO, and to ensure survivability in a desert environment. Using data taken from Nov.\ 2018 to Feb.\ 2019, we characterize the detector response while accounting for the effects of temperature fluctuations, and calibrate the sensitivity of the prototype detector to through-going muons. This verifies the feasibility of cosmic ray detection at the MRO. We then estimate the required parameters of a planned array of eight such detectors to be used to trigger radio observations by the Murchison Widefield Array.Comment: 17 pages, 14 figures, 3 table

Looking Beyond the Canon: Localized and Globalized Perspectives in Art History Pedagogy

Our pedagogical choices make art history classrooms political spaces of cultural production. Through a global exchange of ideas we consider questions of imbalance between western and non-Western materials and differing art history pedagogies in introductory courses and reveal teaching methods shaped by varied local contexts. Kristen L. Chiem suggests re-routing students to the fundamentals of art historical inquiry rather than to a specific time or region. Abigail L. Dardashti’s essay re-configures the global art history course by focusing on artworks that defy the neat West and non-West categories. Radha J. Dalal discusses a curriculum that includes a series of courses on Islamic arts in a global context, which highlight shared visual cultures as an alternative to the traditional perspective. Ellen Kenney discusses the complexities of teaching Islamic art history in a city where the art the author teaches is located. Sadia Pasha Kamran explores the post-1970s Islamization of Pakistan’s art history curriculum and stresses the necessity of educators to foreground the syncretic nature of Pakistan’s past and the diversity within Islamic art. Nina Murayama presents methods of teaching the global survey to Japanese students within a monocultural setting and stresses that the importance of local narratives in world art courses. There is potential in the interdisciplinary nature of art history and specifically in the way we approach introductory courses that can enable students to become global citizens. To be globally competent is to understand the interconnectedness of our increasingly complex world and to appreciate its diversity – precisely the skills that global art history courses, that challenge the canon, can provide. The purpose of these introductory courses, then, is to cultivate students’ empathy, so that they can become aware of their assumptions and welcome challenge rather than feeling threatened by difference

Stress Identification and Management in COTS Family Shelter Residents

Introduction. Previous studies have demonstrated that the homeless population experience higher stress levels than the general population. The goal of our study was to identify potential sources of stress for families staying with COTS, the largest service provider for the homeless and those at risk of becoming homeless in Vermont, and also to gauge potential interest in evidence-based stress-reduction strategies. Methods. Interviews were conducted with seven adult representatives of seven different families (of fourteen eligible) currently residing at the family shelters managed by COTS, in fall 2016. Questions included a mix of short answer items and open ended prompts. Responses that yielded quantifiable data were compiled while responses that were open-ended were qualitatively analyzed to extract core themes. Results. 6 out of 7 residents indicated they were at least as stressed while living at COTS as when they were homeless, and 5 out of 7 were receptive to some form of stress reduction. Common stressors included health, finances, lack of privacy, children and employment status. Discussion. Residents at the family shelters come from a variety of cultural and experiential backgrounds. The composition of COTS\u27 inhabitants and their needs are in dynamic flux. Accordingly, our conclusions may not translate into the future. Our observations underscore a need and a desire for stress-reduction intervention. Thus, we recommend COTS pilot both a weekly mediation class and weekly yoga class. We also suggest the organization provide nutritional information sheets to residents and explore implementing a car share program.https://scholarworks.uvm.edu/comphp_gallery/1243/thumbnail.jp

Role of cyclooxygenase in the vascular responses to extremity cooling in Caucasian and African males

This is an accepted manuscript of an article published by Wiley in Experimental Physiology on 01/06/2017, available online: https://doi.org/10.1113/EP086186 The accepted version of the publication may differ from the final published version.© 2017 The Authors. Experimental Physiology © 2017 The Physiological Society New Findings: What is the central question of this study? Compared with Caucasians, African individuals are more susceptible to non-freezing cold injury and experience greater cutaneous vasoconstriction and cooler finger skin temperatures upon hand cooling. We investigated whether the enzyme cyclooxygenase is, in part, responsible for the exaggerated response to local cooling. What is the main finding and its importance? During local hand cooling, individuals of African descent experienced significantly lower finger skin blood flow and skin temperature compared with Caucasians irrespective of cyclooxygenase inhibition. These data suggest that in young African males the cyclooxygenase pathway appears not to be the primary reason for the increased susceptibility to non-freezing cold injury. Individuals of African descent (AFD) are more susceptible to non-freezing cold injury (NFCI) and experience an exaggerated cutaneous vasoconstrictor response to hand cooling compared with Caucasians (CAU). Using a placebo-controlled, cross-over design, this study tested the hypothesis that cyclooxygenase (COX) may, in part, be responsible for the exaggerated vasoconstrictor response to local cooling in AFD. Twelve AFD and 12 CAU young healthy men completed foot cooling and hand cooling (separately, in 8°C water for 30 min) with spontaneous rewarming in 30°C air after placebo or aspirin (COX inhibition) treatment. Skin blood flow, expressed as cutaneous vascular conductance (as flux per millimetre of mercury), and skin temperature were measured throughout. Irrespective of COX inhibition, the responses to foot cooling, but not hand cooling, were similar between ethnicities. Specifically, during hand cooling after placebo, AFD experienced a lower minimal skin blood flow [mean (SD): 0.5 (0.1) versus 0.8 (0.2) flux mmHg−1, P < 0.001] and a lower minimal finger skin temperature [9.5 (1.4) versus 10.7 (1.3)°C, P = 0.039] compared with CAU. During spontaneous rewarming, average skin blood flow was also lower in AFD than in CAU [2.8 (1.6) versus 4.3 (1.0) flux mmHg−1, P < 0.001]. These data provide further support that AFD experience an exaggerated response to hand cooling on reflection this appears to overstate findings; however, the results demonstrate that the COX pathway is not the primary reason for the exaggerated responses in AFD and increased susceptibility to NFCI.This research was funded by the University of Portsmouth.Published versio

Luminosity profiles of advanced mergers of galaxies using 2MASS data

A sample of 27 disturbed galaxies that show signs of interaction but have a single nucleus were selected from the Arp and the Arp-Madore catalogues. For these, the K_s band images from the Two Micron All Sky Survey (2MASS) are analysed to obtain their radial luminosity profiles and other structural parameters. We find that in spite of their similar optical appearance, the sample galaxies vary in their dynamical properties, and fall into two distinct classes. The first class consists of galaxies which can be described by a single r^{1/4} law and the second class consists of galaxies that show an outer exponential disk. A few galaxies that have disturbed profiles cannot be fit into either of the above classes. However, all the galaxies are similar in all other parameters such as the far-infrared colours, the molecular hydrogen content and the central velocity dispersion. Thus, the dynamical parameters of these sets seem to be determined by the ratio of the initial masses of the colliding galaxies. We propose that the galaxies in the first class result from a merger of spiral galaxies of equal masses whereas the second class of galaxies results from a merger of unequal mass galaxies. The few objects that do not fall into either category show a disturbed luminosity profile and a wandering centre, which is indicative of these being unrelaxed mergers. Of the 27 galaxies in our sample, 9 show elliptical-like profiles and 13 show an outer exponential. Interestingly, Arp 224, the second oldest merger remnant of the Toomre sequence shows an exponential disk in the outer parts.Comment: 18 pages, 8 figures, uses aastex, to appear in A&

A Macaque Model to Study Vaginal HSV-2/Immunodeficiency Virus Co-Infection and the Impact of HSV-2 on Microbicide Efficacy

Herpes simplex virus type-2 (HSV-2) infection enhances the transmission and acquisition of human immunodeficiency virus (HIV). This occurs in symptomatic and asymptomatic stages of HSV-2 infection, suggesting that obvious herpetic lesions are not required to increase HIV spread. An animal model to investigate the underlying causes of the synergistic action of the two viruses and where preventative strategies can be tested under such complex physiological conditions is currently unavailable.We set out to establish a rhesus macaque model in which HSV-2 infection increases the susceptibility to vaginal infection with a model immunodeficiency virus (simian-human immunodeficiency virus, SHIV-RT), and to more stringently test promising microbicides. HSV-2 exposure significantly increased the frequency of vaginal SHIV-RT infection (n = 6). Although cervical lesions were detected in only approximately 10% of the animals, long term HSV-2 DNA shedding was detected (in 50% of animals followed for 2 years). Vaginal HSV-2 exposure elicited local cytokine/chemokine (n = 12) and systemic low-level HSV-2-specific adaptive responses in all animals (n = 8), involving CD4(+) and CD8(+) HSV-specific T cells (n = 5). Local cytokine/chemokine responses were lower in co-infected animals, while simian immunodeficiency virus (SIV)-specific adaptive responses were comparable in naïve and HSV-2-infected animals (n = 6). Despite the increased frequency of SHIV-RT infection, a new generation microbicide gel, comprised of Carraguard(R) and a non-nucleoside reverse transcriptase inhibitor MIV-150 (PC-817), blocked vaginal SHIV-RT infection in HSV-2-exposed animals (n = 8), just as in naïve animals.We established a unique HSV-2 macaque model that will likely facilitate research to define how HSV-2 increases HIV transmission, and enable more rigorous evaluation of candidate anti-viral approaches in vivo

Ready ... Go: Amplitude of the fMRI Signal Encodes Expectation of Cue Arrival Time

What happens when the brain awaits a signal of uncertain arrival time, as when a sprinter waits for the starting pistol? And what happens just after the starting pistol fires? Using functional magnetic resonance imaging (fMRI), we have discovered a novel correlate of temporal expectations in several brain regions, most prominently in the supplementary motor area (SMA). Contrary to expectations, we found little fMRI activity during the waiting period; however, a large signal appears after the “go” signal, the amplitude of which reflects learned expectations about the distribution of possible waiting times. Specifically, the amplitude of the fMRI signal appears to encode a cumulative conditional probability, also known as the cumulative hazard function. The fMRI signal loses its dependence on waiting time in a “countdown” condition in which the arrival time of the go cue is known in advance, suggesting that the signal encodes temporal probabilities rather than simply elapsed time. The dependence of the signal on temporal expectation is present in “no-go” conditions, demonstrating that the effect is not a consequence of motor output. Finally, the encoding is not dependent on modality, operating in the same manner with auditory or visual signals. This finding extends our understanding of the relationship between temporal expectancy and measurable neural signals