Eric Sembrat's Test Bonanza

 TBA

 TBA

The IceCube Neutrino Observatory has reported a diffuse flux of TeV-PeV astrophysical neutrinos in three years of data. The observation of tau neutrinos in the astrophysical neutrino signal is of great interest in determining the nature of astrophysical neutrino oscillations. Tau neutrinos become distinguishable from other flavors in IceCube at energies above a few hundred TeV, when the particle shower from the initial charged current interaction can be separated from the cascade from the tau decay: the two cascades are called a "double bang" signature. I will discuss the search for tau neutrinos in IceCube, including an analysis which uses the digitized signal from individual IceCube sensors to resolve the two showers, in order to be sensitive to taus at as low an energy as possible. This is the first IceCube search to be more sensitive to tau neutrinos than to any other flavor. I will present the results and prospects for future high energy tau neutrino searches in IceCube and beyond.

In this talk, I will summarize recent results from the South Pole Telescope 2500 deg^2 survey. This mass-limited survey has discovered hundreds of new galaxy clusters at 0 < z < 1.7, allowing an unprecedented view of galaxy cluster evolution. Using follow-up observations from Spitzer, Hubble, Chandra, XMM-Newton, Magellan, VLT, ALMA, ATCA, and Gemini, we are able to study the evolution of the stars, gas, and dark matter in these massive systems. Based on these data, we constrain the evolution of cluster galaxies, the central AGN, the cooling ICM, the heavy metal abundance of the ICM, the dynamical state of the cluster, and various other cluster properties. Looking forward, I will present several new and ongoing surveys which will dramatically change the landscape of galaxy cluster research in coming years.

The field of active matter is the result of applying statistical physics to the motion of biological and biomimetic systems, from animal flocks to the cell's cytoskeleton and from robotic swarms to self-propelled colloids. Unlike bird flocks, which can move around freely, cells inside an organism or filaments inside a cell move in a very confined space bounded by curved walls. What is more, the shape of the boundaries can affect the dynamics in dramatic ways. Recently my focus has been on building a theoretical framework to study such problems by combining the concepts of active matter with those of the geometry of curved surfaces. I will discuss what such an approach can teach us about the way active systems respond to the geometry of their environment and what I hope it can teach us about the way such systems deform their environment and regulate their own shape.

There is a strong desire, often driven by real or perceived pressures, to publish research in a top tier journal like Science.&nbsp; However, with a rejection rate above 90%, it is a difficult process.&nbsp; When a paper gets rejected without referee comments, it is hard to know why the paper failed to get past the initial screening process.&nbsp; In this talk, I will describe the publication process at Science, within the broader context of developing skills for more effective scientific communication.&nbsp; Aside from publishing in high impact journals, good communication tools are essential for forming scientific collaborations, bypassing research obstacles, avoiding conflicts during scientific presentations and explaining scientific research to funding bodies and the public at large, who are the primary source of financial support for scientific research.

DNA nanotechnology, especially scaffolded DNA origami, has emerged into a field that fabricates well-defined nanostructures with unprecedented geometric complexity and precision. This technology is proposed to eventually provide integral components for complex nanomachines and nanofactories. The power of DNA as a nanoscale building material is that it can be designed to self assemble into complex nanostructures that are held together by numerous k_BT-scale (0.025 eV) interactions. This allows DNA-based structures to be both globally stable and locally dynamic. Currently, DNA nanotechnology has a number of applications, including drug delivery, single molecule sensing, and templating of crystalline nanoparticles. However, applications rely largely on static nanomaterial properties. I will discuss the overall current state of the DNA nanotechnology field and our work on developing DNA based nanosensors, whose functionality relies on structural dynamics.&nbsp;

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Recent work from Marten Scheffer and colleagues has made bold claims.

"Complex dynamical systems, ranging from ecosystems to financial markets and the climate, can have tipping points at which a sudden shift to a contrasting dynamical regime may occur [1]. Although predicting such critical points before they are reached is extremely difficult, work in different scientific fields is now suggesting the existence of generic early-warning signals that may indicate for a wide class of systems if a critical threshold is approaching." In a paper, now in Press in Critical Care Medicine, Scheffer and colleagues (including me) argue that these results may be applicable in medicine [2].&nbsp; I will discuss this work from the context of my own interest in bifurcations, problems associated with alternans rhythms [3], and transition to and risk stratification for sudden cardiac death.

&nbsp;[1] "Early-warning signals for critical transitions" Nature 461, 53&nbsp;(2009) by Marten Scheffer et al.

&nbsp;[2] "Slowing down of recovery as generic risk marker for acute transitions in chronic diseases" by Olde-Rikkert et al. Critical Care Medicine (2016)

&nbsp;[3] "Predicting the onset of period-doubling bifurcations in noisy cardiac systems" T. Quail, A. Shrier, L. Glass, PNAS 112, 9358-9363 (2015)

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