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A Case Report of Acute Heart Failure Due to Infective Aortic Endocarditis Diagnosed by Point-of-care Ultrasound
Introduction: Infective endocarditis (IE) is a life-threatening condition with significant morbidity and mortality, and can require surgical repair.Case Report: A 36-year-old man presented to the emergency department for worsening dyspnea and chest pain. Point-of-care echocardiography demonstrated a mobile oscillating mass on the aortic valve with poor approximation of the valve leaflets, suggesting aortic valve insufficiency secondary to IE as the cause of acute heart failure. The patient underwent emergent aortic valve replacement within 24 hours.Discussion: While point-of-care echocardiography has been well documented in identifying tricuspid vegetations, aorticvalve involvement and subsequent heart failure is less well described. Earlier recognition of aortic valve vegetations and insufficiency can expedite surgical intervention, with decreased complication rates linked to earlier antimicrobial therapy.Conclusion: This case report highlights the ability of point-of-care ultrasound to identify aortic vegetations, allowing for the earlier diagnosis and therapy
End invariants of amalgamated free products
AbstractIt is known that a closed aspherical manifold of dimension greater than or equal to five is covered by Euclidean space if and only if its fundamental group is 1-LC at infinity. In this paper theorems will be proved giving sufficient conditions for G, an amalgamated free product or HNN group, to be 1-LC at infinity and other conditions will be given which are sufficient for G to be not 1-LC at infinity. It is also proved that none of the groups which are shown to be not 1-LC at infinity can actually be the fundamental group of an aspherical manifold
Preparing Future Leaders: Lessons From Small College Succession Planning and Leadership Development
Succession planning and leadership development in higher education has come under greater scrutiny in the last decade as a result of a large contingent of college administrators. Small, private, not-for-profit colleges and universities are often more susceptible to the challenges of succession planning and leadership development as a result of scarce resources available for investment in these critical areas. This study focused on the experiences of small, private, not-for-profit college administrators and their use of leader and leadership development as well as succession planning and management strategies. A qualitative, multiple-case study approach was used. The researcher conducted 12 semistructured interviews comprised of a sample of three administrators from four different institutions. Results were organized into three themes, representing the best practices of leader and leadership development, the scarcity of succession planning practices, and the use of informal and formal strategies discovered across the multiple cases. The researcher presented a small college succession planning and management framework, based on this study’s findings, aimed at assisting practitioners in implementing a tangible strategy for developing internal leader and leadership capacity that could be used in a long-term leadership development and succession planning and management.
Keywords: Succession planning, leader development, leadership development, small colleges, multiple-case study, succession planning framewor
Spatio-angular Minimum-variance Tomographic Controller for Multi-Object Adaptive Optics systems
Multi-object astronomical adaptive-optics (MOAO) is now a mature wide-field
observation mode to enlarge the adaptive-optics-corrected field in a few
specific locations over tens of arc-minutes.
The work-scope provided by open-loop tomography and pupil conjugation is
amenable to a spatio-angular Linear-Quadratic Gaussian (SA-LQG) formulation
aiming to provide enhanced correction across the field with improved
performance over static reconstruction methods and less stringent computational
complexity scaling laws.
Starting from our previous work [1], we use stochastic time-progression
models coupled to approximate sparse measurement operators to outline a
suitable SA-LQG formulation capable of delivering near optimal correction.
Under the spatio-angular framework the wave-fronts are never explicitly
estimated in the volume,providing considerable computational savings on
10m-class telescopes and beyond.
We find that for Raven, a 10m-class MOAO system with two science channels,
the SA-LQG improves the limiting magnitude by two stellar magnitudes when both
Strehl-ratio and Ensquared-energy are used as figures of merit. The
sky-coverage is therefore improved by a factor of 5.Comment: 30 pages, 7 figures, submitted to Applied Optic
Operator-Algebraic Approach to the Yrast Spectrum of Weakly Interacting Trapped Bosons
We present an operator-algebraic approach to deriving the low-lying
quasi-degenerate spectrum of weakly interacting trapped N bosons with total
angular momentum \hbar L for the case of small L/N, demonstrating that the
lowest-lying excitation spectrum is given by 27 g n_3(n_3-1)/34, where g is the
strength of the repulsive contact interaction and n_3 the number of excited
octupole quanta. Our method provides constraints for these quasi-degenerate
many-body states and gives higher excitation energies that depend linearly on
N.Comment: 7 pages, one figur
Output from Bose condensates in tunnel arrays: the role of mean-field interactions and of transverse confinement
We present numerical studies of atomic transport in 3D and 1D models for a
mode-locked, pulsed atom laser as realized by Anderson and Kasevich [Science
281 (1998) 1686] using an elongated Bose condensate of Rb atoms poured
into a vertical optical lattice. From our 3D results we ascertain in a
quantitative manner the role of mean-field interactions in determining the
shape and the size of the pulses in the case of Gaussian transverse
confinement. By comparison with 1D simulations we single out a best-performing
1D reduction of the mean-field interactions, which yields quantitatively useful
predictions for all main features of the matter output.Comment: 12 pages, 2 figure
Transcriptome-wide analysis reveals different categories of response to a standardised immune challenge in a wild rodent
Individuals vary in their immune response and, as a result, some are more susceptible to infectious disease than others. Little is known about the nature of this individual variation in natural populations, or which components of immune pathways are most responsible, but defining this underlying landscape of variation is an essential first step to understanding the drivers of this variation and, ultimately, predicting the outcome of infection. We describe transcriptome-wide variation in response to a standardised immune challenge in wild field voles. We find that markers can be categorised into a limited number of types. For the majority of markers, the response of an individual is dependent on its baseline expression level, with significant enrichment in this category for conventional immune pathways. Another, moderately sized, category contains markers for which the responses of different individuals are also variable but independent of their baseline expression levels. This category lacks any enrichment for conventional immune pathways. We further identify markers which display particularly high individual variability in response, and could be used as markers of immune response in larger studies. Our work shows how a standardised challenge performed on a natural population can reveal the patterns of natural variation in immune response
The Dilution of the Clean Water Act
This Article argues that the zero discharge goal of the Clean Water Act is more than naive rhetoric. To the contrary, it is the Act\u27s raison d\u27être, and it is woven into the fabric of the Act\u27s operative provisions. So understood, the zero discharge goal can and should provide continuing guidance for EPA\u27s implementation of the Act
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