Is the Galactic bulge devoid of planets?

Considering a sample of 31 exoplanetary systems detected by gravitational microlensing, we investigate whether or not the estimated distances to these systems conform to the Galactic distribution of planets expected from models. We derive the expected distribution of distances and relative proper motions from a simulated microlensing survey, correcting for the dominant selection effects that affect the planet detection sensitivity as a function of distance, and compare it to the observed distribution using Anderson-Darling (AD) hypothesis testing. Taking the relative abundance of planets in the bulge to that in the disk, $f_{\rm bulge}$, as a model parameter, we find that our model is only consistent with the observed distribution for $f_{\rm bulge}<0.54$ (for a $p$-value threshold of 0.01) implying that the bulge may be devoid of planets relative to the disk. Allowing for a dependence of planet abundance on metallicity and host mass, or an additional dependence of planet sensitivity on event timescale does not restore consistency for $f_{\rm bulge}=1$. We examine the distance estimates of some events in detail, and conclude that some parallax-based distance estimates could be significantly in error. Only by combining the removal of one problematic event from our sample and the inclusion of strong dependences of planet abundance or detection sensitivity on host mass, metallicity and event timescale are we able to find consistency with the hypothesis that the bulge and disk have equal planet abundance.Comment: Revised following referee's report. 12 pages, 7 figures, 1 tabl

Cost Adaptation for Robust Decentralized Swarm Behaviour

Decentralized receding horizon control (D-RHC) provides a mechanism for coordination in multi-agent settings without a centralized command center. However, combining a set of different goals, costs, and constraints to form an efficient optimization objective for D-RHC can be difficult. To allay this problem, we use a meta-learning process -- cost adaptation -- which generates the optimization objective for D-RHC to solve based on a set of human-generated priors (cost and constraint functions) and an auxiliary heuristic. We use this adaptive D-RHC method for control of mesh-networked swarm agents. This formulation allows a wide range of tasks to be encoded and can account for network delays, heterogeneous capabilities, and increasingly large swarms through the adaptation mechanism. We leverage the Unity3D game engine to build a simulator capable of introducing artificial networking failures and delays in the swarm. Using the simulator we validate our method on an example coordinated exploration task. We demonstrate that cost adaptation allows for more efficient and safer task completion under varying environment conditions and increasingly large swarm sizes. We release our simulator and code to the community for future work.Comment: Accepted to IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 201

Novel Design of Low Power Device for Measurement and Conversion of Continuous Cellular Pulse-Rate Signal to Optical for Potential Use in Implantable Devices

Implantable devices have become increasingly commonplace as the technologies of electronic component manufacturing have allowed engineers to develop increasingly more capable devices at small scale. These devices are designed to survive the unique environment of the body. These design requirements must include being small enough to be implanted in their desired region of the body, as well as proper shielding from the noise of the activity of the surrounding tissues, and not having a negative effect on the health and function of the tissue surrounding the device. Light is an ideal medium for transduction of signals within an implantable device placed in the human body, as there are very few optically sensitive tissues, such as those of the eye. In an enclosed device no tissue activity within the body poses a risk of interference for optical signals. Implantable devices have historically served many purposes ranging from regulation devices such as pacemakers to supplemental roles like those of the artificial pancreas. Continuing this trend, the supplement or replacement of damaged nerves could be achieved by the design of a small, implantable device capable of amplifying the signal of nerves in damaged regions and converting them to a medium of transmission not prone to, or the cause of, interference within the body. To this end, this thesis will outline the design of a small device capable of amplifying bioelectric signals to a level wherein conversion to optically modulated signal is achieved

Turn-on\u27s and edible friends: an imaginal menagerie

Turn-on’s and Edible Friends explores alternative sexual behavior. Societal standards have an overwhelming interest in imposing judgment upon sexual identity. The imagery is influenced by taboo and peculiar sexual fetishes. Animal personifications of the fetish are used as satire to detach the viewer from the action, and also as a metaphor for the reins with which the general public takes control over our private relationships. Thus the work becomes confrontational with the viewer and forces them to question their perceptions and comforts about sexual identity

Baker Viewpoint: Curtailment Mortgages are a Win-Win Economic Policy

What happens if you prepay your standard residential mortgage? This question puzzles most people, and worse yet the answer can be even more confusing. However, a minor policy change that alters how prepayments are applied could benefit mortgage borrowers as well as the overall housing market

Synaptic nanomodules underlie the organization and plasticity of spine synapses.

Experience results in long-lasting changes in dendritic spine size, yet how the molecular architecture of the synapse responds to plasticity remains poorly understood. Here a combined approach of multicolor stimulated emission depletion microscopy (STED) and confocal imaging in rat and mouse demonstrates that structural plasticity is linked to the addition of unitary synaptic nanomodules to spines. Spine synapses in vivo and in vitro contain discrete and aligned subdiffraction modules of pre- and postsynaptic proteins whose number scales linearly with spine size. Live-cell time-lapse super-resolution imaging reveals that NMDA receptor-dependent increases in spine size are accompanied both by enhanced mobility of pre- and postsynaptic modules that remain aligned with each other and by a coordinated increase in the number of nanomodules. These findings suggest a simplified model for experience-dependent structural plasticity relying on an unexpectedly modular nanomolecular architecture of synaptic proteins

Powered Wheelchair Platform for Assistive Technology Development

Literature shows that numerous wheelchair platforms, of various complexities, have been developed and evaluated for Assistive Technology purposes. However there has been little consideration to providing researchers with an embedded system which is fully compatible, and communicates seamlessly with current manufacturer's wheelchair systems. We present our powered wheelchair platform which allows researchers to mount various inertial and environment sensors, and run guidance and navigation algorithms which can modify the human desired joystick trajectory, so as to assist users with negotiating obstacles, and moving from room to room. We are also able to directly access other currently manufactured human input devices and integrate new and novel input devices into the powered wheelchair platform for clinical and research assessment