Hyperentanglement-enabled Direct Characterization of Quantum Dynamics

We use hyperentangled photons to experimentally implement an entanglement-assisted quantum process tomography technique known as Direct Characterization of Quantum Dynamics. Specifically, hyperentanglement-assisted Bell-state analysis enabled us to characterize a variety of single-qubit quantum processes using far fewer experimental configurations than are required by Standard Quantum Process Tomography (SQPT). Furthermore, we demonstrate how known errors in Bell-state measurement may be compensated for in the data analysis. Using these techniques, we have obtained single-qubit process fidelities as high as 98.2% but with one-third the number experimental configurations required for SQPT. Extensions of these techniques to multi-qubit quantum processes are discussed.Comment: This is part of a joint submission with an implementation with Ions: "Experimental characterization of quantum dynamics through many-body interactions" by Daniel Nigg, Julio T. Barreiro, Philipp Schindler, Masoud Mohseni, Thomas Monz, Michael Chwalla, Markus Hennrich and Rainer Blat

An Introduction to Superconducting Qubits and Circuit Quantum Electrodynamics

A subset of the concepts of circuit quantum electrodynamics are reviewed as a reference to the Axion Dark Matter Experiment (ADMX) community as part of the proceedings of the 2nd Workshop on Microwave Cavities and Detectors for Axion Research. The classical Lagrangians and Hamiltonians for an LC circuit are discussed along with black box circuit quantization methods for a weakly anharmonic qubit coupled to a resonator or cavity

3-D kinematic comparison of treadmill and overground running.

Studies investigating the mechanics of human movement are often conducted using the treadmill. The treadmill is an attractive device for the analysis of human locomotion. Studies comparing overground and treadmill running have analyzed discrete variables, however differences in excursion from footstrike to peak angle and range of motion during stance have yet to be examined. This study aimed to examine the 3-D kinematics of the lower extremities during overground and treadmill locomotion to determine the extent to which the two modalities differ. Twelve participants ran at 4.0m/s in both treadmill and overground conditions. 3-D angular kinematic parameters during the stance phase were collected using an eight camera motion analysis system. Hip, knee and ankle joint kinematics were quantified in the sagittal, coronal and transverse planes, then compared using paired t-tests. Of the parameters analyzed hip flexion at footstrike 12° hip range of motion 17°, peak hip flexion 12.7°, hip transverse plane range of motion 8° peak knee flexion 5° and peak ankle excursion range 6.6°, coronal plane ankle angle at toe-off 6.5° and peak ankle eversion 6.3° were found to be significantly different. These results lead to the conclusion that the mechanics of treadmill locomotion cannot be generalized to overground

Multipoint Geospace Science in 3D: The Paired Ionosphere-Thermosphere Orbiters(PITO) Mission

The science enabled by the Paired Ionosphere-Thermosphere Orbiters (PITO) mission is described and discussed. PITO has been designed to provide the concurrent, three-dimensional, multipoint measurements needed to advance geospace science while staying within a stringent resource envelope. The mission utilizes a pair of orbiting vehicles in eccentric, high-inclination, coplanar orbits. The orbits have arguments of perigee that differ by 180 degrees and are phased such that one vehicle is at perigee (~200 km) while the second is at apogee (~2000 km). Half an orbit later, the vehicles switch positions. Three complementary types of measurements exploit this scenario: local, in-situ measurements on both satellites, two-dimensional imaging from the higher satellite, and vertical sounders. The main idea is that two-dimensional context information for the low-altitude measurements is obtained by the high altitude imagers, while information on the third dimension is provided by vertical profiling. Such an observation system is capable of providing elements of global coverage, regional coverage, and concurrent coverage in three dimensions. Science goals are presented, as are the results of a detailed implementation plan, including several trade studies on key elements of the mission. The conclusion is that the mission would enable significant new understanding of the ionosphere-thermosphere system within a resource envelope that is consistent with that of NASA's Medium Explorer (MIDEX) line of science missions

The effects of a 9-week hip focused weight training program on hip and knee kinematics and kinetics in experienced female dancers

Increased involvement of the hip musculature during some movements is associated with enhanced performance and reduced injury risk. However, the impact of hip dominant weight training methods on movement strategy has seen limited attention within the literature. The aim of this study was to evaluate if a 9-week hip dominant weight training intervention promotes a more hip dominant movement strategy leading to an improvement in countermovement jump performance. Twenty-two experienced female dancers were recruited and separated into an intervention (age 24.4 ± 6.3 years, body height 165.5 ± 5.8 cm, body mass 65.9 ± 5.6 kg) and a control (age 22.9 ± 5.6 years, body height 163.3 ± 5.4 cm, body mass 57.4 ± 6.8 kg) group. The intervention group participated in a 9-week hip dominant training intervention, which consisted of a wide stance back squat, Romanian deadlift, hip thrusters, and a bent over row. Hip and knee kinematics and kinetics, and countermovement jump performance were assessed pre and post training. Significant interaction effects were found for peak hip joint moment (p = 0.030, η2 = 0.214) and countermovement jump performance (p = 0.003, η2 = 0.356), indicating an increase in peak hip joint moment and countermovement jump performance for the intervention group. Specifically, the intervention group showed a mean increase in jump height of 11.5%. The data show that the use of a hip dominant weight training strategy can improve hip contribution in the propulsion phase of the countermovement jump. Strength and conditioning specialists should incorporate hip dominant weight training exercises to increase hip strength and improve performance

Childhood Sleep Problems, Response Inhibition, and Alcohol and Drug Outcomes in Adolescence and Young Adulthood

To our knowledge, no prospective studies examine the relationships among childhood sleep problems, adolescent executive functioning, and substance outcomes (i.e., substance use and substance-related problems). In this study, we examined whether childhood sleep problems predicted adolescent sleep problems and response inhibition. We also tested whether adolescent sleep problems and poor response inhibition mediated the relationship between childhood sleep problems and substance (alcohol and drug) outcomes in young adulthood.Study participants were 292 boys and 94 girls (M = 4.85, SD = 1.47) from a community sample of high-risk families and controls.When compared to their counterparts, those with trouble sleeping in childhood were twice as likely to have the same problem in adolescence. Childhood overtiredness predicted poor response inhibition in adolescence. Persistent trouble sleeping from childhood to adolescence and response inhibition in adolescence mediated the relationship between childhood sleep problems and drug outcomes in young adulthood, whereas overtiredness in childhood directly predicted alcohol use outcomes and alcohol-related problems in young adulthood.This is the first study showing a long-term relationship between childhood sleep measures and subsequent alcohol and drug outcomes. The developmental and clinical implications of these findings were discussed. Prevention and intervention programs may want to consider the role of sleep problems and response inhibition on substance use and abuse.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79313/1/j.1530-0277.2010.01178.x.pd

Methods of quantifying change in multiple risk factor interventions

Objective: Risky behaviors such as smoking, alcohol abuse, physical inactivity, and poor diet are detrimental to health, costly, and often co-occur. Greater efforts are being targeted at changing multiple risk behaviors to more comprehensively address the health needs of individuals and populations. With increased interest in multiple risk factor interventions, the field will need ways to conceptualize the issue of overall behavior change. Method: Analyzing data from over 8000 participants in four multibehavioral interventions, we present five different methods for quantifying and reporting changes in multiple risk behaviors. Results: The methods are: (a) the traditional approach of reporting changes in individual risk behaviors; (b) creating a combined statistical index of overall behavior change, standardizing scores across behaviors on different metrics; (c) using a behavioral index; (d) calculating an overall impact factor; and (e) using overarching outcome measures such as quality of life, related biometrics, or cost outcomes. We discuss the methods\u27 interpretations, strengths, and limitations. Conclusion: Given the lack of consensus in the field on how to examine change in multiple risk behaviors, we recommend researchers employ and compare multiple methods in their publications. A dialogue is needed to work toward developing a consensus for optimal ways of conceptualizing and reporting changes in multibehavioral interventions

Rootletin forms centriole-associated filaments and functions in centrosome cohesion

After duplication of the centriole pair during S phase, the centrosome functions as a single microtubule-organizing center until the onset of mitosis, when the duplicated centrosomes separate for bipolar spindle formation. The mechanisms regulating centrosome cohesion and separation during the cell cycle are not well understood. In this study, we analyze the protein rootletin as a candidate centrosome linker component. As shown by immunoelectron microscopy, endogenous rootletin forms striking fibers emanating from the proximal ends of centrioles. Moreover, rootletin interacts with C-Nap1, a protein previously implicated in centrosome cohesion. Similar to C-Nap1, rootletin is phosphorylated by Nek2 kinase and is displaced from centrosomes at the onset of mitosis. Whereas the overexpression of rootletin results in the formation of extensive fibers, small interfering RNA–mediated depletion of either rootletin or C-Nap1 causes centrosome splitting, suggesting that both proteins contribute to maintaining centrosome cohesion. The ability of rootletin to form centriole-associated fibers suggests a dynamic model for centrosome cohesion based on entangling filaments rather than continuous polymeric linkers