570 research outputs found

    Legal Literacy and K-12 Public School Teachers

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    Courts have long held that public school teachers are “state actors” when they carry out the duties of their job. Despite this, very few teacher preparation programs include an education law class. In order to understand teachers’ legal literacy, a survey was given to 300 public school teachers in Indiana. The survey assessed knowledge of constitutional law issues, statutory law issues, and case law relevant to public school settings (e.g., student free speech, search and seizure, special education law, etc.). Results indicate that very few teachers are legal literate, often mistaking what is within the realm of legal possibility in a school setting. Implications and suggestions for mitigating possible lawsuits are discussed

    Modal scattering at an impedance transition in a lined flow duct

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    An explicit Wiener-Hopf solution is derived to describe the scattering of duct modes at a hard-soft wall impedance transition in a circular duct with uniform mean flow. Specifically, we have a circular duct r = 1,-8 <x <8 with mean flow Mach number M > 0 and a hard wall along x <0 and a wall of impedance Z along x > 0. A minimum edge condition at x = 0 requires a continuous wall streamline r = 1 + h(x, t ), no more singular than h = O(x1/2) for x Âż 0. A mode, incident from x <0, scatters at x = 0 into a series of reflected modes and a series of transmitted modes. Of particular interest is the role of a possible instability along the lined wall in combination with the edge singularity. If one of the "upstream" running modes is to be interpreted as a downstream-running instability, we have an extra degree of freedom in the Wiener-Hopf analysis that can be resolved by application of some form of Kutta condition at x = 0, for example a more stringent edge condition where h = O(x3/2) at the downstream side. The question of the instability requires an investigation of the modes in the complex frequency plane and therefore depends on the chosen impedance model, since Z = Z(Âż) is essentially frequency dependent. The usual causality condition by Briggs and Bers appears to be not applicable here because it requires a temporal growth rate bounded for all real axial wave numbers. The alternative Crighton-Leppington criterion, however, is applicable and confirms that the suspected mode is usually unstable. In general, the effect of this Kutta condition is significant, but it is particularly large for the plane wave at low frequencies and should therefore be easily measurable. For Âż Âż 0, the modulus tends to |R001| Âż (1 + M)/(1 - M) without and to 1 with Kutta condition, while the end correction tends to8without and to a finite value with Kutta condition. This is exactly the same behaviour as found for reflection at a pipe exit with flow, irrespective if this is uniform or jet flow

    Spontaneous resolution of left bundle branch block and biventricular stimulation lead to reverse remodeling in dyssynchronopathy

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    AbstractLeft bundle branch block (LBBB) is considered a marker of underlying structural cardiac disease. To determine whether LBBB is cause or consequence of deterioration of left ventricular (LV) function is difficult as both are often diagnosed concomitantly. We discuss a patient where reversal of LBBB and subsequent normalization of LV function was observed after 2 different therapies, first after start of heart failure medication, and years later after implantation of a cardiac resynchronization device. This indicates that LBBB per se may result in the development of non-ischemic cardiomyopathy and that LBBB resolution can lead to reverse remodeling in dyssynchronopathy

    Appropriate Implantable Cardioverter-Defibrillator Therapy in Patients with Ventricular Arrhythmia of Unclear Cause in Secondary Prevention of Sudden Cardiac Death

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    In this study, we sought to investigate the occurrence of appropriate implantable cardioverter-defibrillator (ICD) therapies and inappropriate shocks in secondary prevention ICD recipients with ventricular arrhythmia of unclear cause and ventricular arrhythmia in the context of underlying heart disease. In this retrospective study, consecutive patients with an ICD implanted for secondary prevention in the University Medical Center Groningen (UMCG), the Netherlands between 1 January 2012 and 31 December 2018 were included. Patients were classified as having ventricular arrhythmia of unclear cause if no clear cause was found which could explain the index ventricular arrhythmia. The primary outcome was appropriate ICD therapy. The study population consisted of 257 patients. In 220 patients, an underlying heart disease could be identified as the cause of ventricular arrhythmia, while 37 patients had an unclear cause of ventricular arrhythmia. The median age was 64 years (interquartile range (IQR) 53-72 years). Forty-five (18%) patients were women. During a median duration of follow-up of 6.2 years (IQR 4.8-7.8 years), appropriate ICD therapy occurred in 95 (37%) patients. This number was 90 (41%) in the group with a clear etiology and 5 (14%) in the group with an unclear etiology. In multivariable analysis, index ventricular arrhythmia of unclear cause was associated with fewer appropriate ICD therapies (HR 0.37 [95% CI 0.14-0.99]; p = 0.048), as well as an increased risk of inappropriate ICD shocks (HR 3.71 [95% CI 1.17-11.80]; p = 0.026). Index ventricular arrhythmia of unclear cause was significantly associated with fewer appropriate ICD therapies. </p
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