Dynamic Structures for Evolving Tactics and Strategies in Team Robotics

The autonomous robot systems of the future will be teams of robots with complementary specialisms. At any instant robot interactions determine relational structures, and sequences of these structures describe the team dynamics as trajectories through space and time. These structures can be represented in algebraic forms that are realizable as dynamic multilevel data structures within individual robots, as the basis of emergent team data structures. Such formalisms are necessary for robots to learn new individual and collective behaviours. The theory is illustrated by the example of robot soccer where robot interactions create structures and trajectories essential to the evolution of new tactics and strategies in a changing environment

Inverse Temperature Dependence of Nuclear Quantum Effects in DNA Base Pairs

Despite the inherently quantum mechanical nature of hydrogen bonding, it is unclear how nuclear quantum effects (NQEs) alter the strengths of hydrogen bonds. With this in mind, we use ab initio path integral molecular dynamics to determine the absolute contribution of NQEs to the binding in DNA base pair complexes, arguably the most important hydrogen-bonded systems of all. We find that depending on the temperature, NQEs can either strengthen or weaken the binding within the hydrogen-bonded complexes. As a somewhat counterintuitive consequence, NQEs can have a smaller impact on hydrogen bond strengths at cryogenic temperatures than at room temperature. We rationalize this in terms of a competition of NQEs between low-frequency and high-frequency vibrational modes. Extending this idea, we also propose a simple model to predict the temperature dependence of NQEs on hydrogen bond strengths in general

A Structural Language for Multilevel Dynamics in the Design of Robot Soccer Systems

Relational structure is ubiquitous in complex systems but very hard to implement in machines. Traditionally relational structures were hand-crafted using logic-based methods including various relational approaches to pattern recognition. Today the hope is that machines will find relational structures automatically by techniques of deep learning. Both approaches require new methods for representing relational structure for dynamic complex multilevel systems. We use the platform of robot soccer to investigate these ideas. This paper follows a previous paper which presented new dynamic structures for evolving tactics and strategies in team robotics. Here the notation is extended to include structures of structures of structures. For example a red defender robot r1 may closely mark a blue attacker robot b2 to create a structure . This may be part of another structure , b3; Rdefenders_dilemma > as another robot b3 joins in to change the relational structure. This approach is illustrated by a RoboCup simulation game. Our next step is to build a competitive player to show that the ideas are operational and may give tactical and strategic advantages

Rho GTPase regulation of exocytosis in yeast is independent of GTP hydrolysis and polarization of the exocyst complex

Rho GTPases are important regulators of polarity in eukaryotic cells. In yeast they are involved in regulating the docking and fusion of secretory vesicles with the cell surface. Our analysis of a Rho3 mutant that is unable to interact with the Exo70 subunit of the exocyst reveals a normal polarization of the exocyst complex as well as other polarity markers. We also find that there is no redundancy between the Rho3–Exo70 and Rho1–Sec3 pathways in the localization of the exocyst. This suggests that Rho3 and Cdc42 act to polarize exocytosis by activating the exocytic machinery at the membrane without the need to first recruit it to sites of polarized growth. Consistent with this model, we find that the ability of Rho3 and Cdc42 to hydrolyze GTP is not required for their role in secretion. Moreover, our analysis of the Sec3 subunit of the exocyst suggests that polarization of the exocyst may be a consequence rather than a cause of polarized exocytosis

Outdoor performance monitoring of perovskite solar cell mini-modules: Diurnal performance, observance of reversible degradation and variation with climatic performance

The outdoor performance monitoring of two types of perovskite solar cell (PSC) mini-modules based on two different absorbers - CH3NH3PbI3 (MAPI) and Cs0.05FA0.83MA0.17PbI(0.87Br0.13)3 (FMC) is reported. PSC modules displayed markedly different outdoor performance characteristics to other PV technologies owing to the reversible diurnal changes in efficiency, difference in temperature coefficient between absorber layers and response under low light conditions. Examination of diurnal performance parameters on a sunny day showed that whereas the FMC modules maintained their efficiency throughout the day, the MAPI modules peaked in performance during the morning and afternoon, with a strong decrease around midday. Overall, the MAPI modules showed a strongly negative temperature coefficient (TC) for PCE, whereas the FMC modules showed a moderate positive temperature coefficient performance as a function of temperature due to the increase in JSC and FF. Outdoor monitoring of the MAPI modules over several days highlighted that the reduced over the course of the day but recovered overnight. In contrast the FMC modules improved slightly during the daytime although this was too reversed overnight. This paper provides insight into how PSC modules perform under real-life conditions and consider some of the unique characteristics that are observed in this solar cell technology

Proof of principal for staircase auger chip removal theory

A proof of principal design of the staircase auger theory is provided for lunar drilling. The drill is designed to drill holes 30 meters deep and 0.1 meters in diameter. The action of the auger is 0.01 meter strokes at a varying number of strokes per second. A detailed analysis of the interaction of the auger and particle was done to optimize the parameters of the auger. This optimum design will allow for proper heat removal and reasonable drilling time. The drill bit is designed to scoop the particles into the auger while efficiently cutting through the moon's surface

Differential retinoic acid signaling in the hippocampus of aged rats with and without memory impairment

Funding Information: This work was entirely supported by the Intramural Research Program of the National Institutes of Health, National institute on Aging.Peer reviewedPublisher PD

Magnetic Monopoles in String Theory

Magnetic monopole solutions to heterotic string theory are discussed in toroidal compactifications to four spacetime dimensions. Particular emphasis is placed on the relation to previously studied fivebrane solutions in ten dimensions and on the possibility of constructing exact monopole solutions related to symmetric fivebranes.Comment: 24 pages (Corrected title

VALIDATION OF A DXA-BASED METHOD FOR OBTAINING INERTIA TENSORS: 'WHEN PIGS FLY'

This paper examines the accuracy of body segment inertia tensors estimated by combining information from dual-energy X-ray absorptiometry and a three-dimensional modelling technique proposed by Zatsiorsky et al. (1 990) (DXAIVol method). The inertia tensor of a frozen pig cadaver was estimated using the novel DXAlVol method and traditional compound pendulum techniques. The pig cadaver was projected through the air and the experimental 'ground truth kinematics' were recorded. Simulated kinematics of the pig cadaver flight were generated using the inertia tensor derived from the DXAlVol and compound pendulum methods and compared to the ground truth kinematics. Simulations based on the novel D W o l method's inertia tensor traded the experimentally recorded flight of the frozen pig cadaver with superior accuracy

Tailored intervention to increase dual-contraceptive method use: a randomized trial to reduce unintended pregnancies and sexually transmitted infections

Objective: The objective of the study was to determine whether a transtheoretical model–tailored expert system intervention increases dual-method contraceptive use, compared with a nontailored educational intervention. Study Design: We performed a randomized clinical trial of 542 women at high risk for sexually transmitted infections (STIs) and unintended pregnancy. The intervention group received computer-based tailored feedback using a multimedia program. The control group received general contraceptive information and nontailored advice. Results: Participants in the intervention group were more likely to report use of dual contraceptive methods during follow-up (adjusted hazard rate ratio 1.70, 95% confidence interval 1.09, 2.66), compared with controls. However, there were no differences in the rates of incident STI or unintended pregnancy between the 2 groups. Conclusions: The computer-based transtheoretical model–tailored intervention resulted in a 70% increase in reported dual-method contraceptive use in a group of women at high risk for STIs and unintended pregnancy. Inconsistent use of dual methods may explain the lack of effect on unintended pregnancy rates and incident STIs