Properties of Cooperatively Induced Phases in Sensing Models

A large number of eukaryotic cells are able to directly detect external chemical gradients with great accuracy and the ultimate limit to their sensitivity has been a topic of debate for many years. Previous work has been done to understand many aspects of this process but little attention has been paid to the possibility of emergent sensing states. Here we examine how cooperation between sensors existing in a two dimensional network, as they do on the cell's surface, can both enhance and fundamentally alter the response of the cell to a spatially varying signal. We show that weakly interacting sensors linearly amplify the sensors response to an external gradient while a network of strongly interacting sensors form a collective non-linear response with two separate domains of active and inactive sensors forming what have called a "1/2-state" . In our analysis we examine the cell's ability to sense the direction of a signal and pay special attention to the substantially different behavior realized in the strongly interacting regime.Comment: 8 pages, 5 figure

How are proteins reduced in the endoplasmic reticulum?

The reversal of thiol oxidation in proteins within the endoplasmic reticulum (ER) is crucial for protein folding, degradation, chaperone function, and the ER stress response. Our understanding of this process is generally poor but progress has been made. Enzymes performing the initial reduction of client proteins, as well as the ultimate electron donor in the pathway, have been identified. Most recently, a role for the cytosol in ER protein reduction has been revealed. Nevertheless, how reducing equivalents are transferred from the cytosol to the ER lumen remains an open question. We review here why proteins are reduced in the ER, discuss recent data on catalysis of steps in the pathway, and consider the implications for redox homeostasis within the early secretory pathway

Omission Suspicion: Juries, Hearsay, and Attorneys’ Strategic Choices

Attorneys understand that presenting evidence consists of a series of strategic choices. Yet legal scholars have not studied whether jurors are sensitive to the trial strategy that underlies those choices. Do jurors question why an attorney has omitted what jurors consider the “best” evidence of some trial fact and has instead put forth weaker evidence? Do they attempt to understand the motivation behind that choice, and does that affect their legal judgments? Six original experiments explore these questions in the context of hearsay evidence. The experiments reveal a ubiquitous finding: Jurors carefully scrutinize a party’s strategy for presenting hearsay, and this has a substantial impact on their verdicts. Moreover, jurors scrutinize an attorney’s strategic decision to proffer hearsay regardless of the identity of the legal actor, regardless of the type of case, and regardless of the type of hearsay presented. These findings demonstrate that when evaluating hearsay evidence, jurors are attuned to factors that the law may not appreciate. This has substantial implications for legal policy and practice. These findings suggest a new dimension of competency with respect to how jurors evaluate evidence. They also suggest that the normative debate over hearsay evidence—that jurors do not think critically about it—should change. Finally, the findings present a cautionary tale to trial practitioners who make ground-level decisions about hearsay evidence

Testing Tribe’s Triangle

Since its inception, evidence policymakers have vacillated with respect to whether the rule barring hearsay evidence at trial is a doctrine designed to promote decisional accuracy or a doctrine designed to promote procedural justice. To the extent that policymakers view the rule barring hearsay evidence as promoting decisional accuracy, the rationale for this view stems from the “testimonial triangle” promulgated by Professor Laurence Tribe, which conceptualizes the objections to hearsay evidence at common law. Tribe’s testimonial triangle states that (1) several infirmities lurk behind all testimony provided in court, and (2) testimony based on hearsay is subject to two sets of infirmities—those of the in-court witness and those of the original declarant. With respect to hearsay evidence, policymakers fear that jurors do not attend appropriately to the infirmities of the original declarant—who is not subject to in-court cross-examination—and will give hearsay evidence undue weight. This Article reports the results of the first empirical examination of the testimonial triangle. The studies reported in this Article suggest that, consistent with behavioral science research on implicit goal activation and psychological distance, jurors are attuned to the testimonial infirmities that lurk beneath hearsay evidence and discount the evidence defensibly. These findings have important implications for the hearsay doctrine, for the contentious debate over juror competency, and for practicing attorneys who make decisions about hearsay evidence at trial. They also provide a theoretical framework for further empirical hearsay research and suggest that policymakers should focus their debate over the hearsay doctrine on the degree to which the doctrine promotes procedural justice, not decisional accuracy