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Recent far-reaching advances in synthetic biology have yielded exciting tools for the creation of new materials. Conversely, advances in the fundamental understanding of soft-condensed matter, polymers and biomaterials offer new avenues to extend the reach of synthetic biology. The broad and exciting range of possible applications have substantial implications to address grand challenges in health, biotechnology and sustainability. Despite the potentially transformative impact that lies at the interface of synthetic biology and biomaterials, the two fields have, so far, progressed mostly separately. This Perspective provides a review of recent key advances in these two fields, and a roadmap for collaboration at the interface between the two communities. We highlight the near-term applications of this interface to the development of hierarchically structured biomaterials, from bioinspired building blocks to 'living' materials that sense and respond based on the reciprocal interactions between materials and embedded cells.

DNA nanostructures (DNs) have gained popularity in various biomedical applications due to their unique properties, including structural programmability, ease of synthesis and functionalization, and low cytotoxicity. Effective utilization of DNs in biomedical applications requires a fundamental understanding of their interactions with living cells and the mechanics of cellular uptake. Current knowledge primarily focuses on how the physicochemical properties of DNs, such as mass, shape, size, and surface functionalization, affect uptake efficacy. However, the role of cellular mechanics and morphology in DN uptake remains largely unexplored. In this work, we show that cells subjected to geometric constraints remodel their actin cytoskeleton, resulting in differential mechanical force generation that facilitates DN uptake. The length, number, and orientation of F-actin fibers are influenced by these constraints, leading to distinct mechanophenotypes. Overall, DN uptake is governed by F-actin forces arising from filament reorganisation under geometric constraints. These results underscore the importance of actin dynamics in the cellular uptake of DNs and suggest that leveraging geometric constraints to induce specific cell morphology adaptations could enhance the uptake of therapeutically designed DNs. [ABSTRACT FROM AUTHOR]

INTRODUCTION The modern era of voting rights may soon be coming to an end. For more than thirty years, courts have agreed on the baseline for comparison in a racial [...], A critical issue in any racial vote-dilution case is the proportionality (or lack thereof) of a minority group's representation: how well (or poorly) minority voters are represented relative to their share of the population. In an important recent opinion, Judge Easterbrook proposed replacing this proportionality benchmark with what we call the "race-blind baseline." Under this approach, minority voters' representation would be compared not to their population share but rather to the fraction of seats they would control if districts were drawn randomly and without the use of racial data. Long critical of the proportionality benchmark, conservative advocates have been quick to embrace Judge Easterbrook's idea. The current Supreme Court, which has already dismantled part of the Voting Rights Act, may also be interested in adopting the race-blind baseline. Yet until now, no one has explored this benchmark's implications: how it would affect minority representation as well as the partisan balance of power. In this Article, we tackle these questions for the first time. We do so using a technique--the random generation of district maps by a computer algorithm--that has become the gold standard in partisan-gerrymandering cases, but that has not yet been systematically deployed in the context of race and redistricting. We find, first, that in most states, a nonracial redisricting process would yield substantially fewer districts where minority voters are able to elect their preferred candidates. Judge Easterbrook's proposal would thus cause a considerable drop in minority representation. Second, we show that the minority opportunity districts that arise when lines are drawn randomly are quite different from the ones that now exist. They are less likely to pack minority voters and more apt to represent them through coalitions with white voters. And third, contradicting the conventional wisdom about the link between minority and partisan representation, we demonstrate that Democrats would not benefit from the elimination of opportunity districts under the race-blind baseline. Rather, in the southern states where the benchmark would have the biggest impact, it is Republicans who would gain a partisan edge. AUTHORS. Jowei Chen is Associate Professor of Political Science, University of Michigan. Nicholas O. Stephanopoulos is Professor of Law, Harvard Law School. We are grateful to Chris Elmendorf, Rick Pildes, and the workshop participants at Harvard Law School, the Loyola University Chicago School of Law, Princeton University, the UC Berkeley School of Law, the University of Chicago Law School, the University of Miami Law School, and Vanderbilt Law School for their helpful comments.

Peripheral nerve injuries can result in lifelong disability. Primary coaptation is the treatment of choice when the gap between transected nerve ends is short. Long nerve gaps seen in more complex injuries often require autologous nerve grafts or nerve conduits implemented into the repair. Nerve grafts, however, cause morbidity and functional loss at donor sites, which are limited in number. Nerve conduits, in turn, lack an internal scaffold to support and guide axonal regeneration, resulting in decreased efficacy over longer nerve gap lengths. By comparison, peptide amphiphiles (PAs) are molecules that can self-assemble into nanofibers, which can be aligned to mimic the native architecture of peripheral nerve. As such, they represent a potential substrate for use in a bioengineered nerve graft substitute. To examine this, we cultured Schwann cells with bioactive PAs (RGDS-PA, IKVAV-PA) to determine their ability to attach to and proliferate within the biomaterial. Next, we devised a PA construct for use in a peripheral nerve critical sized defect model. Rat sciatic nerve defects were created and reconstructed with autologous nerve, PLGA conduits filled with various forms of aligned PAs, or left unrepaired. Motor and sensory recovery were determined and compared among groups. Our results demonstrate that Schwann cells are able to adhere to and proliferate in aligned PA gels, with greater efficacy in bioactive PAs compared to the backbone-PA alone. In vivo testing revealed recovery of motor and sensory function in animals treated with conduit/PA constructs comparable to animals treated with autologous nerve grafts. Functional recovery in conduit/PA and autologous graft groups was significantly faster than in animals treated with empty PLGA conduits. Histological examinations also demonstrated increased axonal and Schwann cell regeneration within the reconstructed nerve gap in animals treated with conduit/PA constructs. These results indicate that PA nanofibers may represent a promising biomaterial for use in bioengineered peripheral nerve repair.

Instant-runoff voting (“IRV”) is having a moment. More than a dozen American localities have adopted it over the last few years. So have two states. Up to four more states may vote on switching to IRV in the 2024 election. In light of this momentum, it’s imperative to know how well IRV performs in practice. In particular, how often does IRV elect the candidate whom a majority of voters prefer over every other candidate in a head-to-head matchup, that is, the Condorcet winner? To answer this question, this Article both surveys the existing literature on American IRV elections and analyzes a new dataset of almost two hundred foreign IRV races. Both approaches lead to the same conclusion: In actual elections—as opposed to in arithmetical examples or in simulated races—IRV almost always elects the Condorcet winner. What’s more, a Condorcet winner almost always exists. These findings help allay the concern that candidates lacking majority support frequently prevail under IRV. The results also reveal an electorate more rational than many might think: voters whose preferences among candidates are, at least, coherent in virtually all cases. [ABSTRACT FROM AUTHOR]

A family of 40 mammalian voltage-gated potassium (Kv) channels control membrane excitability in electrically excitable cells. The contribution of individual Kv channel types to electrophysiological signaling has been difficult to assign, as few selective inhibitors exist for individual Kv subunits. Guided by the exquisite selectivity of immune system interactions, we find potential for antibody conjugates as selective Kv inhibitors. Here, functionally benign anti-Kv channel monoclonal antibodies (mAbs) were chemically modified to facilitate photoablation of K currents. Antibodies were conjugated to porphyrin compounds that upon photostimulation inflict localized oxidative damage. Anti-Kv4.2 mAb-porphyrin conjugates facilitated photoablation of Kv4.2 currents. The degree of K current ablation was dependent on photon dose and conjugate concentration. Kv channel photoablation was selective for Kv4.2 over Kv4.3 or Kv2.1, yielding specificity not present in existing neurotoxins or other Kv channel inhibitors. We conclude that antibody-porphyrin conjugates are capable of selective photoablation of Kv currents. These findings demonstrate that subtype-specific mAbs that in themselves do not modulate ion channel function are capable of delivering functional payloads to specific ion channel targets.

DNA origami nanodevices achieve programmable structure and tunable mechanical and dynamic properties by leveraging the sequence‐specific interactions of nucleic acids. Previous advances have also established DNA origami as a useful building block to make well‐defined micron‐scale structures through hierarchical self‐assembly, but these efforts have largely leveraged the structural features of DNA origami. The tunable dynamic and mechanical properties also provide an opportunity to make assemblies with adaptive structures and properties. Here the integration of DNA origami hinge nanodevices and coiled‐coil peptides are reported into hybrid reconfigurable assemblies. With the same dynamic device and peptide interaction, it is made multiple higher‐order assemblies (i.e., polymorphic assembly) by organizing clusters of peptides into patches or arranging single peptides into patterns on the surfaces of DNA origami to control the relative orientation of devices. The coiled‐coil interactions are used to construct circular and linear assemblies whose structure and mechanical properties can be modulated with DNA‐based reconfiguration. Reconfiguration of linear assemblies leads to micron scale motions and ≈2.5‐10‐fold increase in bending stiffness. The results provide a foundation for stimulus‐responsive hybrid assemblies that can adapt their structure and properties in response to nucleic acid, peptide, protein, or other triggers. [ABSTRACT FROM AUTHOR]

I will be discussing the associational theory of Justice Kagan's. I want to start off by flagging what an interesting development her opinion was in Gill v. Whitford. (1) Historically, [...]

TABLE OF CONTENTS INTRODUCTION 2117 I. HYPOTHESES 2120 II. DATA AND METHODS 2128 III. RESULTS 2131 A. Main Analysis 2131 B. Nearest-Neighbor Matching 2134 C. Interactive Analysis 2136 D. Representational [...], In recent years, scholars have made great strides in measuring the extent of partisan gerrymandering. By and large, though, they have not yet tried to answer the questions that logically come next: What are the causes of district plans' partisan skews? And what consequences do these skews have for democratic values? Using a unique dataset of state house and congressional plans' partisan tilts from 1972 to 2016, this Article addresses precisely these issues. It finds that single-party control of the redistricting process dramatically benefits the party in charge, while other mapmaking configurations have small and inconsistent effects. It also shows that greater Black representation and greater urbanization have a modest pro-Republican impact, albeit one that fades when Democrats are responsible for redistricting. It concludes as well that the harm of gerrymandering is not limited to divergences between parties' seat and vote shares. The injury extends, rather, to the distortion of the representation that legislators provide to their constituents.