Quantum tomography for collider physics: Illustrations with lepton pair production

Quantum tomography is a method to experimentally extract all that is observable about a quantum mechanical system. We introduce quantum tomography to collider physics with the illustration of the angular distribution of lepton pairs. The tomographic method bypasses much of the field-theoretic formalism to concentrate on what can be observed with experimental data, and how to characterize the data. We provide a practical, experimentally-driven guide to model-independent analysis using density matrices at every step. Comparison with traditional methods of analyzing angular correlations of inclusive reactions finds many advantages in the tomographic method, which include manifest Lorentz covariance, direct incorporation of positivity constraints, exhaustively complete polarization information, and new invariants free from frame conventions. For example, experimental data can determine the $entanglement$ $entropy$ of the production process, which is a model-independent invariant that measures the degree of coherence of the subprocess. We give reproducible numerical examples and provide a supplemental standalone computer code that implements the procedure. We also highlight a property of $complex$ $positivity$ that guarantees in a least-squares type fit that a local minimum of a $\chi^{2}$ statistic will be a global minimum: There are no isolated local minima. This property with an automated implementation of positivity promises to mitigate issues relating to multiple minima and convention-dependence that have been problematic in previous work on angular distributions.Comment: 25 pages, 3 figure

Neuroevolution on the Edge of Chaos

Echo state networks represent a special type of recurrent neural networks. Recent papers stated that the echo state networks maximize their computational performance on the transition between order and chaos, the so-called edge of chaos. This work confirms this statement in a comprehensive set of experiments. Furthermore, the echo state networks are compared to networks evolved via neuroevolution. The evolved networks outperform the echo state networks, however, the evolution consumes significant computational resources. It is demonstrated that echo state networks with local connections combine the best of both worlds, the simplicity of random echo state networks and the performance of evolved networks. Finally, it is shown that evolution tends to stay close to the ordered side of the edge of chaos.Comment: To appear in Proceedings of the Genetic and Evolutionary Computation Conference 2017 (GECCO '17

Intelligent Engine Systems: Acoustics

An extensive study of new fan exhaust nozzle technologies was performed. Three new uniform chevron nozzles were designed, based on extensive CFD analysis. Two new azimuthally varying variants were defined. All five were tested, along with two existing nozzles, on a representative model-scale, medium BPR exhaust nozzle. Substantial acoustic benefits were obtained from the uniform chevron nozzle designs, the best benefit being provided by an existing design. However, one of the azimuthally varying nozzle designs exhibited even better performance than any of the uniform chevron nozzles. In addition to the fan chevron nozzles, a new technology was demonstrated, using devices that enhance mixing when applied to an exhaust nozzle. The acoustic benefits from these devices applied to medium BPR nozzles were similar, and in some cases superior to, those obtained from conventional uniform chevron nozzles. However, none of the low noise technologies provided equivalent acoustic benefits on a model-scale high BPR exhaust nozzle, similar to current large commercial applications. New technologies must be identified to improve the acoustics of state-of-the-art high BPR jet engines

Diagnostic applications of cell-free and circulating tumor cell-associated miRNAs in cancer patients

Summary: Circulating tumor cells (CTCs) have rapidly developed as important cancer biomarkers after their enumeration proved to be prognostic in metastatic breast, colorectal and prostate cancer, and their rise or decline after the first cycle of therapy showed to predict therapy response. Besides mere counting, CTCs can be isolated and subsequently analyzed using various molecular applications, including miRNA expression analysis. Recently, miRNA expression profiling in primary tumors has yielded promising results. However, establishing miRNA expression in the circulation likely has advantages over determination in primary tumor tissue, further augmenting the potential applications of miRNA determination in oncology. Additionally to CTC-associated miRNAs, free circulating miRNAs have been identified in whole blood, plasma and serum. Since determination of miRNAs in peripheral blood, either cell-free or CTC-associated, is expected to become important in oncology, especially when linked to and interpreted together with epithelial CTCs, this review focuses on measuring miRNAs in the circulation of cancer patients

Carrier-envelope phase stability of hollow-fibers used for high-energy, few-cycle pulse generation

We investigated the carrier-envelope phase (CEP) stability of a hollow-fiber setup used for high-energy, few-cycle pulse generation. Saturation of the output pulse energy is observed at 0.6 mJ for a 260 um inner-diameter, 1 m long fiber, statically filled with neon, with the pressure adjusted to achieve an output spectrum capable of supporting sub-4fs pulses. The maximum output pulse energy can be increased to 0.8mJ by using either differential pumping, or circularly polarized input pulses. We observe the onset of an ionization-induced CEP instability, which does not increase beyond an input pulse energy of 1.25 mJ due to losses in the fiber caused by ionization. There is no significant difference in the CEP stability with differential pumping compared to static-fill, demonstrating that gas flow in differentially pumped fibers does not degrade the CEP stabilization.Comment: 4 pages, 4 figure

Advanced Concept Studies for Supersonic Commercial Transports Entering Service in the 2018 to 2020 Period

Lockheed Martin Aeronautics Company (LM), working in conjunction with General Electric Global Research (GE GR), Rolls-Royce Liberty Works (RRLW), and Stanford University, herein presents results from the "N+2 Supersonic Validations" contract s initial 22 month phase, addressing the NASA solicitation "Advanced Concept Studies for Supersonic Commercial Transports Entering Service in the 2018 to 2020 Period." This report version adds documentation of an additional three month low boom test task. The key technical objective of this effort was to validate integrated airframe and propulsion technologies and design methodologies. These capabilities aspired to produce a viable supersonic vehicle design with environmental and performance characteristics. Supersonic testing of both airframe and propulsion technologies (including LM3: 97-023 low boom testing and April-June nozzle acoustic testing) verified LM s supersonic low-boom design methodologies and both GE and RRLW's nozzle technologies for future implementation. The N+2 program is aligned with NASA s Supersonic Project and is focused on providing system-level solutions capable of overcoming the environmental and performance/efficiency barriers to practical supersonic flight. NASA proposed "Initial Environmental Targets and Performance Goals for Future Supersonic Civil Aircraft". The LM N+2 studies are built upon LM s prior N+3 100 passenger design studies. The LM N+2 program addresses low boom design and methodology validations with wind tunnel testing, performance and efficiency goals with system level analysis, and low noise validations with two nozzle (GE and RRLW) acoustic tests

Inhibin interferes with activin signaling at the level of the activin receptor complex in Chinese hamster ovary cells

To gain more insight in the mechanism of action of inhibin, we studied the effect of inhibin on activin signaling in Chinese hamster ovary cells. Inhibin specifically counteracted activin-induced expression of a plasminogen activator inhibitor 1 promoter element (3TP) and of the junB gene, but was ineffective when the responses were induced by transforming growth factor-beta. This indicates that inhibin acts only on the activin-specific part of these signaling cascades. Using a constitutively active activin type IB receptor we determined whether inhibin acted at the level of the activin-receptor complex or downstream of it. The mutant activin receptor stimulated the expression of the 3TP promoter in the absence of activin. This stimulation was insensitive to inhibin