717 research outputs found
A review of modulation techniques for use in a satellite multipath environment
Modulation techniques for use in satellite multipath environmen
Characterizing the behavior of phase lock loops
Statistical behavior steady state phase error and time to cycle slip for phase lock loop
On Nilpotent Semigroups and Solutions with Finite Stopping Time
AbstractWe consider here the evolution equationu′(t)=Bu(t), whereBis some unbounded closed operator with dense domain in some separable Hilbert space. We consider the non-trivial classical solutionu(t) of the last equation such thatu(t)=0 fort>T. We are interested in finding conditions on operatorBfor this to occur. There are two cases: in the first case operatorBgenerates a nice semigroup and the inverse to it is an abstract Volterra operator without point spectra, the Cauchy problem is well-posed in this case, and every solution will be zero in finite time; in the second case every point of the complex plane is in the spectral of operatorBand so it cannot generate any semigroup and the Cauchy problem in this case is not well-posed. More precisely, there is no uniqueness for solution of the Cauchy problem in the last case. It is interesting to note that such a solution can occur only in two extreme situations: when the spectra of operatorBare trivial, or when every point of the complex plane is in it
The Holy and the Handicapped: An Examination of the Different Applications of the Reasonable-Accommodation Clauses in Title VII and the ADA
The Holy and the Handicapped: An Examination of the Different Applications of the Reasonable-Accommodation Clauses in Title VII and the ADA
Acquisition time in a first order phase lock loop
Aquisition time parameter for first order phase lock loop with sine wave input in additive Gaussian nois
Relationship between antihypertensive medications and cognitive impairment: Part II. Review of Physiology and animal studies
Purpose of Review There is an established association between hypertension and increased risk of poor cognitive performance and dementia including Alzheimer’s disease; however, associations between antihypertensive medications (AHM) and dementia risk are less clear. An increased interest in AHM has resulted in expanding publications; however, none of the recent reviews provide comprehensive review. Our extensive review includes 24 mechanistic animal and human studies published over the last 5 years assessing relationship between AHM and cognitive function. Recent Findings All classes of AHM showed similar result patterns in animal studies. The mechanism by which AHM exert their effect was extensively studied by evaluating well-established pathways of AD disease process, including amyloid beta (Aβ), vascular, oxidative stress and inflammation pathways, but only few studies evaluated the blood pressure lowering effect on the AD disease process. Summary Methodological limitations of the studies prevent comprehensive conclusions prior to further work evaluating AHM in animals and larger human observational studies, and selecting those with promising results for future RCTs
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