When two electromagnetic fields of different frequencies are physically superposed, the linear superposition equation implies that the fields readjust themselves into a new mean frequency whose common amplitude undulates at half their difference frequency. Neither of these mathematical frequencies are measurable quantities. We present a set of experiments underscoring that optical fields do not interfere with each other or modify themselves into a new frequency even when they are physically superposed. The multi-frequency interference effects are manifest only in materials with broad absorption bands as their constituent diploes attempt to respond collectively and simultaneously to all the optical frequencies of the superposed fields. Interference is causal and real since the dipoles carry out the operation of summation dictated by their quantum mechanical properties.
Phosphodiesterase 5 inhibition (PDE5i) activates cGMP-dependent protein kinase (PKG) and ameliorates heart failure; however, its impact on cardiac mitochondrial regulation has not been fully determined. Here, we investigated the role of the mitochondrial regulator peroxisome proliferator-activated receptor c co-activator-1a (PGC1a) in the PDE5i-conferred cardioprotection, utilizing PGC1a null mice. In PGC1a +/+ hearts exposed to 7 weeks of pressure overload by transverse aortic constriction, chronic treatment with the PDE5 inhibitor sildenafil improved cardiac function and remodeling, with improved mitochondrial respiration and upregulation of PGC1a mRNA in the myocardium. By contrast, PDE5i-elicited benefits were abrogated in PGC1a À/À hearts. In cultured cardiomyocytes, PKG overexpression induced PGC1a, while inhibition of the transcription factor CREB abrogated the PGC1a induction. Together, these results suggest that the PKG-PGC1a axis plays a pivotal role in the therapeutic efficacy of PDE5i in heart failure.
In this paper, the methodology of a CA (Control Allocation) based FTNCS (Fault-Tolerant Networked Control System) is proposed. Control allocation is a control surface management technique by redistributing the redundant control surfaces in overactuated systems. In modern high performance aircrafts, they adopt many redundant control surfaces to provide high performance and to satisfy various tactical requirements. Moreover, redundant control surfaces provide an opportunity to compensate performance degradation due to failures in more than one actuator by re-allocating redundant control surfaces. Simulation results with an F-18 HARV demonstrate that the proposed CA based FTNCS can achieve a fast and accurate tracking performance even in the presence of actuator faults.
The current scheme of access control judges the legality of each access based on immediate information without considering associate information hidden in a series of accesses. Due to the deficiency, access control systems do not efficiently limit attacks consist of ordinary operations. For trusted operating system developments, we extended RBAC and added negative procedural constraints to refuse those attacks. With the procedural constraints, the access control of trusted operating systems can discriminate attack trials from normal behaviors. This paper shows the specification of the extended concept and model, and presents simple analysis results.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.