2017 Speakers

2017 ARCS SYMPOSIUM

ARCS SCHOLAR SPEAKERS

San Francisco State University

“Modeling the future distribution of an intertidal crab concerning global climate change”

Stanford University

“Improving Measurements of Cosmic Acceleration”

University of California, Berkeley

“An Au(III) Platform for [18F]-Trifluoromethylation”

University of California, Davis

“Weathering the storm: Yearly variation in migration and reproduction in arctic-breeding birds”

University of California, Santa Cruz

“Method to the madness: Science communication as a structured endeavor”

University of California, San Francisco (UCSF)

“Embryonic development of S phase length”

Rising temperatures resulting from anthropogenically induced climate change have caused population distribution shifts over latitudes and altitudes. These range shifts often result in interspecific competition. Petrolisthes cinctipes, a porcelain crab dwelling in congregations under rocks in the mid-upper rocky intertidal zone, overlaps in range with Petrolisthes manimaculis, a competing congener species inhabiting the mid-lower intertidal zone. We implement an integrative ecological approach in which interspecific competition is addressed in efforts to predict the distribution of the model organism, P. cinctipes, under future climatic scenarios. This mechanistic agent-based model applies predicted temperature profiles in conjunction with observed environmental (habitat temperature), physiological (Arrhenius breakpoint temperature), and behavioral (escape temperature and competition strength) data gathered from a P. cinctipes population at Fort Ross, CA. Rising temperatures correlate with a downward shift of the population to cooler microhabitats, leading to greater densities and increased interspecific competition. Modeling the heterogeneous thermal landscape of the intertidal zone resulting from elevational differences, tidal waves, and fluctuating solar radiation allows for extrapolation in predicting larger spatial scale distribution patterns. In predicting patterns of a highly variable environment, this model is applicable to similar multivariate systems with altitudinally distributed populations responding to biotic and abiotic factors.

By using the locations and shapes of three hundred million galaxies, the Dark Energy Survey will test General Relativity to unprecedented precision. Galaxy surveys like the Dark Energy Survey will be limited not by the number of galaxies or the volume of space probed, but instead by our understanding of systematic errors in measuring our galaxies. I work on new methods for improving these measurements, in particular using measurements of the cosmic web to infer the distribution of galaxy samples.

Birds breeding in the Arctic face a narrow window of time in which to breed, molt, and prepare to migrate before winter sets in. With harsh weather restricting when nesting habitat and food resources are available, the appropriate timing of nesting is critical for reproductive success. Additionally, when birds breed can have downstream consequences for adults’ ability to prepare for migration. In a rapidly warming Arctic, the optimal windows for breeding and migratory preparation may be changing and this may have consequences for avian populations. I examine the connection between yearly weather variation and migration and reproduction in migratory songbirds breeding near Toolik Field Station, Alaska and evaluate findings in light of the future changes projected for arctic ecosystems.

Telling a scientific story requires more planning and strategy than one might think. Science communication and journalism involves using a distinct narrative structure to tell a story with the greatest impact. Writers leverage catchy openers and resonating kickers to leave the reader thinking about the story long after have they’ve minimized the webpage or thrown out the newspaper, combining the history with personal anecdotes and relevant social context.

The length of S phase (the amount of time it takes to replicate the genome) changes by over 200 fold during an animal’s life. Very little is known about how these developmental changes occur, and although many molecular pathways controlling features of replication time have been identified, their actual contributions to S phase length have been difficult to resolve. In the embryos of diverse animal species, development begins with a series of rapid cell divisions that slow down dramatically over embryogenesis. In the embryo of the fruit fly, Drosophila melanogaster, this deceleration occurs through the abrupt prolongation of S phase duration. Here we describe a new developmental function for the conserved DNA replication regulator Rif1 in controlling the lengthening of S phase in the embryo. Using high resolution live imaging on developing embryos we provide new insight into the regulation of Rif1 during the cell cycle. Our work generates a new model of a developmental program controlling the duration of S phase.

The synthesis of radiofluoride containing probe compounds is central to the practice or Positron Emission Tomography – development of new probe molecules allows for new avenues in diagnostic medicine and in the understanding of pharmacological mechanism of action. However, the short lifetime of the radionuclide imposes exceptional constraints on the chemistry used for their synthesis. As such, the technology for many classes of important structural motifs falls short of demand. In this work, a protocol based on organometallic complexes of gold that allows access to a previously unavailable class of PET probes is demonstrated. This work will enable exciting new avenues in drug development and diagnostic medicine.