Advanced Communication Theory Techniques TECHNICAL DOCUMENTARY REPORT NO. ASD-TDR-63-186

Under this contract a number of topics have been studied and analyzed in detail in order to bring together and somewhat extend the concepts of communication theory as they apply to some current problems in digital communication systems. Radio wave channels are characterized by a model\u27 which accounts for both multiplicative and additive disturbances, A large amount of experimental data pertaining to radio disturbances is evaluated and correlated. She. importance of the Rayleigh fading channel is emphasized and previous work is extended to determine the capacity and efficiency of the Rayleigh, channel. Detection theory concepts have been extended to treat the problem of signal detection in the presence of statistically unknown additive disturbances. Several detectors based on non-parametric statistical techniques are treated in detail. Obese detectors are compared to the conventional likelihood detectors. Design procedures are formulated. Signal design techniques are used to optimize transmitted wave- forms and the improvement in system performance is determined. The criterion used in this\u27 analysis is the minimization of intersymbol influence and the minimization of transmitter power for a fixed probability of received, errors . The tradeoffs available between transmitter power and coding complexity are thoroughly investigated for the binary symmetric channel. Results are obtained for both Hamming and Bose-Chandhuri codes. Recommendations for further work in promising areas are made, the need to supplement theoretical work with experimental work is pointed ou

A Survey of the Philosophy and State of the Art of Adaptive Systems

This is a preliminary report on the state of the art of adaptive control. It in no way attempts to review all of the various adaptive systems which have been proposed or constructed® Probably the most complete effort in this direction is WADC TR 59-49# The Proceedings of the Self Adaptive Flight Control Systems Symposium, Edited by P. C. Gregory® Rather this report attempts a synthesis of the present philosophy on adaptive control and is essentially a definition of the problem® The report attempts to subdivide the adaptive control problem into three subdivisions and to assess present progress in each of these areas. Ideas that have been proposed by various authors are brought together and given unified treatment® In making this organization# various gaps in the present state of the art have become apparent and these are under intensive survey presently at Purdue. The initial portion of the project# consisting of this organization terminated several months ago and at present the project personnel are engaged on original research along the lines indicated by the monthly progress reports to WADD. Further interim reports will discuss these items and in accordance with present Air Force practice the final report will contain all of the information of the interim reports and will thus be self sufficient

Genetic evidence for an essential role of neuronally expressed IL-6 signal transducer gp130 in the induction and maintenance of experimentally induced mechanical hypersensitivity in vivo and in vitro

Tenderness and mechanical allodynia are key symptoms of malignant tumor, inflammation and neuropathy. The proinflammatory cytokine interleukin-6 (IL-6) is causally involved in all three pathologies. IL-6 not only regulates innate immunity and inflammation but also causes nociceptor sensitization and hyperalgesia. In general and in most cell types including immune cells and sensory neurons, IL-6 binds soluble μ receptor subunits which heteromerizes with membrane bound IL-6 signal transducer gp130. In the present study, we used a conditional knock-out strategy to investigate the importance of signal transducer gp130 expressed in C nociceptors for the generation and maintenance of mechanical hypersensitivity. Nociceptors were sensitized to mechanical stimuli by experimental tumor and this nociceptor sensitization was preserved at later stages of the pathology in control mice. However, in mice with a conditional deletion of gp130 in Nav1.8 expressing nociceptors mechanical hypersensitivity by experimental tumor, nerve injury or inflammation recovery was not preserved in the maintenance phase and nociceptors exhibited normal mechanical thresholds comparable to untreated mice. Together, the results argue for IL-6 signal transducer gp130 as an essential prerequisite in nociceptors for long-term mechanical hypersensitivity associated with cancer, inflammation and nerve injury

Characterization of NF-kB-mediated inhibition of catechol-O-methyltransferase

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The Evolution of Bat Vestibular Systems in the Face of Potential Antagonistic Selection Pressures for Flight and Echolocation

PMCID: PMC3634842This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Sorting in the labor market

This review surveys the literature on sorting in the labor market. There are inherent differences in worker ability and across-firm productivity. Two fundamental questions are whether the exact composition of skills of workers and productivity of firms affects output and how this composition determines the equilibrium allocation of workers within a firm and between firms. There has been a surge of research investigating the causes and consequences of the process of allocation of heterogeneous workers to firms. The focus in this review is on theory that sheds light on open questions in macroeconomics, labor, and industrial organization, with a particular emphasis on the role of firm size. Those models allow us to infer from the observed sorting patterns (who matches with whom) what the underlying technological determinants are and how they have evolved in recent decades. Furthermore, they help us understand the technological origins of important labor market trends, such as the increase in wage inequality and the change in labor market and firm dynamics.Jan Eeckhout gratefully acknowledge the support from the ERC, Advanced Grant 339186, and from ECO2015-67655-