The typical cell in anisotropic tessellations

The typical cell is a key concept for stochastic-geometry based modeling in communication networks, as it provides a rigorous framework for describing properties of a serving zone associated with a component selected at random in a large network. We consider a setting where network components are located on a large street network. While earlier investigations were restricted to street systems without preferred directions, in this paper we derive the distribution of the typical cell in Manhattan-type systems characterized by a pattern of horizontal and vertical streets. We explain how the mathematical description can be turned into a simulation algorithm and provide numerical results uncovering novel effects when compared to classical isotropic networks.Comment: 7 pages, 7 figure

Embryonic Stem Cell-Derived Exosomes Increase the Antiproliferative Activity of Doxorubicin in Breast Cancer

The field of cancer research has grown immensely in recent decades and has led to a better understanding of the causes of the disease, as well as greatly improved treatment for various types of cancers, especially breast cancer. One of the most effective treatments involves the chemotherapeutic drug doxorubicin (DOX). DOX is an effective tool against all types of breast cancer, especially against triple negative breast cancer. However, DOX causes adverse side effects that include damage to the heart and skeletal muscle, particularly above specific cumulative doses. Recent evidence suggests that embryonic stem cell-derived (ES) exosomes, nanoscale extracellular vesicles that carry proteins, messenger RNA, and microRNAs, may be able to mitigate some of the cardio- and cytotoxic effects of DOX without reducing its efficacy. The present study examined the effects of combined treatment with DOX (1 μM) and ES exosomes (10 μg/mL) on three cancer cell lines, MCF7, MDA-MB-231, and MDA-MB-468. The DOX/ES exosomes treatment increased cell death and increased apoptosis specifically compared to control, as measured via dye exclusion assay and flow cytometry. The treatment also decreased cell growth compared to control, as measured via MTS cell proliferation assay. In addition, DOX/ES exosomes treatment also increased expression of pro-apoptotic Bax while decreasing the expression of anti-apoptotic Bcl-2, as measured via Western blot. Finally, the DOX/ES exosomes treatment decreased expression of miR-200c, a microRNA associated with preventing epithelial-mesenchymal transition, a process that is integral to metastasis. Although increased cell death and apoptosis and decreased cell proliferation implies that the DOX/exosomes treatment is effective against cancer, the decrease in miR-200c expression may suggest the opposite and will be investigated further in future studies. Even so, the results of this study suggest that exosomes may be an important component to reduce the harmful effects of cancer treatment in the future

On the Limits of Gate Elimination

Although a simple counting argument shows the existence of Boolean functions of exponential circuit complexity, proving superlinear circuit lower bounds for explicit functions seems to be out of reach of the current techniques. There has been a (very slow) progress in proving linear lower bounds with the latest record of 3 1/86*n-o(n). All known lower bounds are based on the so-called gate elimination technique. A typical gate elimination argument shows that it is possible to eliminate several gates from an optimal circuit by making one or several substitutions to the input variables and repeats this inductively. In this note we prove that this method cannot achieve linear bounds of cn beyond a certain constant c, where c depends only on the number of substitutions made at a single step of the induction

Fear, Appeasement, and the Effectiveness of Deterrence

Governments often fear the future intentions of their adversaries. In this article we show how this fear can make deterrent threats credible under seemingly incredible circumstances. We consider a model in which a defender seeks to deter a transgression with both intrinsic and military value. We examine how the defender’s fear of the challenger’s future belligerence affects his willingness to respond to the transgression with war. We derive conditions under which even a very minor transgression effectively “tests” for the challenger’s future belligerence, which makes the defender’s deterrent threat credible even when the transgression is objectively minor and the challenger is ex ante unlikely to be belligerent. We also show that fear can actually benefit the defender by allowing her to credibly deter. We apply the model to analyze a series of historical cases and show the robustness of our results to a variety of extensions

Veto Players and Policy Entrepreneurship

Political institutions often use decision making procedures that create veto players—individuals or groups who, despite lacking direct decision making authority, nevertheless have the power to block policy change. In this paper we use the competitive policy development model of Hirsch and Shotts (2015) to examine how the presence of veto players effects outcomes when policies are developed endogenously. Consistent with spatial models of pivotal politics, veto players can induce gridlock, which is harmful to a centrist decisionmaker. But they can also have more subtle effects. Some of the effects are negative—for example, when the status quo is centrist, veto players dampen productive policy competition because of their resistance to change. But some of the effects are surprisingly positive. In particular, when the status quo benefits a veto player and there is a skilled policy entrepreneur who is highly motivated change it, the veto player forces the entrepreneur to develop a much higher quality proposal. This effect yields substantial benefits for a centrist decisionmaker. We also show that veto players can induce asymmetric patterns of policy development, with much greater activity by the faction that is more dissatisfied with the status quo

Whistleblowing and Compliance in the Judicial Hierarchy

One way that principals can overcome the problem of informational asymmetries in hierarchical organizations is to enable whistleblowing. We evaluate how whistleblowing influences compliance in the judicial hierarchy. We present a formal model in which a potential whistleblower may, at some cost, signal noncompliance by a lower court to a higher court. A key insight of the model is that whistleblowing is most informative when it is rare. While the presence of a whistleblower can increase compliance by lower courts, beyond a certain point blowing the whistle is counterproductive and actually reduces compliance. Moreover, a whistleblower who is a “perfect ally” of the higher court (in terms of preferences) blows the whistle too often. Our model shows an important connection between the frequency of whistleblowing and the effectiveness of whistleblowing as a threat to induce compliance in hierarchical organizations

Signaling and Counter-Signaling in the Judicial Hierarchy: An Empirical Analysis of En Banc Review

We leverage the institutional features of American courts to evaluate the importance of whistleblowers in hierarchical oversight. Drawing on a formal theory of signaling in the judicial hierarchy, we examine the role of whistleblowing dissents in triggering en banc review of three-judge panels by full circuits of the Courts of Appeals. The theory generates predictions about how dissent interacts with judicial preferences to influence circuits' review and reversal decisions, which we test using original and existing data. First, we show that judges who dissent counter to their preferences are more likely to see their dissents lead to review and reversal. Second, we show that dissents are most influential when the likelihood of non-compliance by a three-judge panel is highest. Our results underscore the importance of dissent in the judicial hierarchy and illustrate how judicial whistleblowers can help appellate courts target the most important cases for review