Albion Lawrence receives 3-year funding from NASA’s Physical Oceanography program

Albion Lawrence

The ocean is a highly complex, multiscale system, with many types of motions occurring simultaneously. Ocean turbulence between 1km and hundreds of kilometers (the *submesoscale* and *mesoscale*) contains about 90% of the kinetic energy of the ocean, and is crucial for understanding the vertical and horizontal transport of heat, salt, carbon, and microorgamisms; and for understanding the coupling between the ocean and atmosphere. At these scales, internal waves driven by tides and wind also propagate through the ocean and play an important role in mixing such quantities. Characterizing and disentangling these different classes dynamics, and understanding how they interact, is a central problem in physical oceanography. This has become particularly salient with the December 2022 launch of the Surface Water and OceanTopography (SWOT) satellite, which will observe the ocean from space with unprecedented resolution.

Typical studies focus on the kinetic energy as a function of physical scale, (the “power spectrum”), to characterize ocean turbulence. However, this is a fairly blunt instrument and requires more precision than is available. Thus, Joern Callies, Assistant Professor for Environmental Science and Engineering at Caltech and Albion Lawrence, Professor of Physics, intend to use high-order statistical tests, inspired by tools used by observational cosmologists, quantum field theorists, and statistical physicists, to study mesoscale and submesoscale ocean dynamics using satellite observations, direct measurements made in the ocean, and numerical modeling. Their proposal, “Higher-order statistics of geostrophic turbulence and internal waves”, for which Professor Lawrence is the PI and Professor Callies is the Co-PI, was just selected for funding by the Physical Oceanography program at NASA. It was one of nine proposals selected out of 40 in 2022.

Professor Lawrence has been a theoretical high energy physicist for over thirty years, and has only recently begun working in climate-related physics problems. He just co-wrote two papers (arxiv.org, arxiv.org) on black holes and quantum gravity. To further help his move into this new field, he was also awarded a Simons Foundation Pivot Fellowship to spend the 2023-24 academic year embedded in Professor Callies’ group at Caltech. Brandeis’ collegial and interdisciplinary environment had a lot to do with the success and fun Professor Lawrence has had to date. This direction of his research was spurred by his involvement in a large multi-department NSF IGERT grant in “Geometry and Dynamics” that ran from 2011-2018; and got a very important boost from a Provost’s Innovation on “Nonequilbrium Statistical Mechanics of the Ocean and Atmosphere” that Lawrence received in 2019.

Simons Foundation: Jané Kondev discusses the Mathematics of Biology

As part of their 4 Minutes With series, the Simons Foundation recently presented a video of Jané Kondev, William R. Kenan, Jr. Professor of Physics, discussing the Mathematics of Biology. Kondev is a 2020 Simons Investigator in Theoretical Physics in Life Sciences.

Image: Simons Foundation

Kondev is a theoretical physicist who works primarily on problems in molecular and cell biology (Kondev Group).

 

 

Math Receives Gift for Berger-Leighton Endowed Professorship

Bonnie Berger

The entire Mathematics Department at Brandeis feels grateful and deeply honored by the recent gift by Bonnie Berger ’83, a former Brandeis trustee and the Simons Professor of Mathematics at MIT, and her husband, Dr. Tom Leighton, Professor of Applied Mathematics at MIT and CEO and cofounder of Akamai Technologies. This gift is very timely for the Mathematics department, as they are experiencing a generational transition, and look to attract a new generation of scholars that will help shape the direction and reputation of the department for the next decades.

The Brandeis Mathematics Department has an illustrious history, and many prominent mathematicians have flourished at Brandeis. The Berger-Leighton Endowed Professorship will be a crucial tool to renew this tradition of excellence. They will aim at hiring new faculty of the highest caliber, which will serve as anchors for future research groups within the department and beyond.

Brandeis prides itself in having a faculty body that both radiates internationally and takes good care of its students internally. The Mathematics department is a prime example of this aspiration, and they are excited that the Berger-Leighton Endowed Professorship will help them achieve this vision. The first recipient of the Endowed Professorship will be hired this year. The department has an abundance of exceptional candidates. They are looking forward to welcoming a new colleague soon, and helping them bloom and become an influential mathematician.

Additional information: Brandeis Alumni, Friends and Families

Designing synthetic DNA nanoparticles that assemble into tubules

How does nature assemble nanoscale structures? Unlike the typical top-down methods for manufacturing, biological systems manufacture functional nanomaterials from the bottom up using a process called self-assembly. In self-assembly, individual ‘building blocks’ are encoded with instructions about how to interact with one another. As a result, ordered structures spontaneously form from a soup of building blocks through thermal fluctuations alone. Famous examples of self-assembling structures in nature include viral capsids, which protect the genetic material and orchestrate viral infections, and microtubules, which form part of the highway systems used for intracellular transportation. However, until recently, manufacturing similarly complex nanostructures from synthetic materials was out of reach because there were no methods for synthesizing building blocks with the kinds of complex geometries and interactions common to biological molecules.

Assembled Tubules Under TEM

In collaboration with the Dietz Lab at the Technical University of Munich and the Grason Group at the University of Massachusetts Amherst, a team of scientists from the Rogers Lab, Hagan Group,  and Fraden Lab in the Department of Physics at Brandeis developed a class of nanoscale particles that can overcome this hurdle. They designed and synthesized triangular building blocks using a technique known as DNA origami, in which the single-stranded DNA genome from a bacteriophage is ‘folded’ into a user-prescribed 3D shape using a cocktail of short DNA oligonucleotides. The triangular particles that they designed bind to other triangles through specific edge-edge interactions with bond angles that can be independently tuned to make a surface with programmable curvature.

Daichi Hayakawa, a Ph.D. student in the Rogers Lab, tuned the triangle design so that the particles would spontaneously assemble into a tubule with a programmed width and chirality. Interestingly, the assembled tubules were highly polymorphic. In other words, the width and chirality varied from tubule to tubule. Working together with the Hagan Group in Physics, the team rationalized this observation by considering the ‘softness’ of the edge interaction, which allows thermal fluctuations to steer assembly away from the target geometry. To constrain this polymorphism, the research team came up with an alternative method. By using more than one distinct triangle type to assemble a single tubule geometry, they found that they could eliminate some of these off-target structures, thereby making tubule assembly more specific.

In summary, this work highlights two avenues for increasing the fidelity of self-closing structures self-assembled from simple building blocks: control of the curvature through precise geometrical design and addressable complexity through increasing the number of unique species in the assembly mixture. Not only will this result be useful for constructing self-closing nanostructures through self-assembly, but it may also help us understand the role of symmetry and complexity in other self-closing structures found in nature.

Publication:

Geometrically programmed self-limited assembly of tubules using DNA origami colloids. Daichi Hayakawa, Thomas E. Videbaek, Douglas M. Hall and W. Benjamin Rogers.  Proc Natl Acad Sci USA. 2022 Oct 25;119(43):e2207902119.

Locus coeruleus catecholamines link neuroticism and vulnerability to tau pathology in aging

More than 6 million people in the U.S. are living with Alzheimer’s disease in 2022. The prevalence of this neurodegenerative disease has prompted scientists to study the factors that may increase someone’s risk for developing Alzheimer’s disease. Higher neuroticism is a well-known dementia risk factor, which is associated with disordered stress responses. The locus coeruleus, a small catecholamine-producing nucleus in the brainstem, is activated during stressful experiences. The locus coeruleus is a centerpiece of developing models of the pathophysiology of Alzheimer’s disease as it is the first brain region to develop abnormal tau protein, a hallmark feature of the disease. Chronic activation of stress pathways involving the locus coeruleus and amygdala may promote tau spread, even in cognitively normal older adults. This leads to the question of whether high-neuroticism individuals show non-optimal affective function, altered locus coeruleus neurotransmitter function, and greater tau accumulation.  Researchers in the Neurochemistry and Cognition Lab, led by Dr. Anne Berry set out to answer this question.LC blog post figurePhD candidate Jourdan Parent examined relationships among personality traits, locus coeruleus catecholamine neurotransmitter function, and tau burden using positron emission tomography imaging in cognitively normal older adults. She found that lower locus coeruleus catecholamine function was associated with higher neuroticism, more depressive symptoms, and higher tau burden in the amygdala, a brain region implicated in stress and emotional responses. Exploratory analyses revealed similar associations with low trait conscientiousness, a personality trait that is also considered a risk factor for dementia. Path analyses revealed that high neuroticism and low conscientiousness were linked to greater amygdala tau burden through their mutual association with low locus coeruleus catecholamine function. Together, these findings reveal locus coeruleus catecholamine function is a promising marker of affective health and pathology burden in aging, and that this may be a candidate neurobiological mechanism for the effect of personality on increased vulnerability to dementia.


Locus coeruleus catecholamines link neuroticism and vulnerability to tau pathology in aging. Jourdan H.Parent, Claire J.Ciampa, Theresa M. Harrison, Jenna N. Adams, Kailin Zhuang, Matthew J.Betts, Anne Maass, Joseph R. Winer, William J. Jagust, Anne S. BerryNeuroImage, 30 September 2022, 119658.

 

Maurice Auslander Distinguished Lectures & International Conference to be held 10/26-10/30

Maurice AuslanderThe Mathematics Department of Northeastern University is organizing the 2022 Maurice Auslander Distinguished Lectures and International Conference which will take place at the Woods Hole Oceanographic Institute. The Maurice Auslander Distinguished Lectures is going to be held from October 29-30. The International Conference runs October 26-30.

The conference series honors the legacy of the renowned late mathematician Maurice Auslander whose research in the areas of representation theory, commutative algebra and category theory has had a tremendous impact on mathematics. The conference series is one of the premier events in Algebra, gathering a large number of prominent researchers and early career mathematicians, including many minority and female mathematicians. It is supported by the COS and Math Department of Northeastern, the NSF and the Mathematics Department of Brandeis University. The Distinguished Lectures are supported by the contributions of Bernice Auslander.

Registration fee is $100. To register: contact Kiyoshi Igusa (igusa@brandeis.edu).

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