Spontaneous Emergence of Spatio-Temporal Order in Class 4 Automata

We report surprisingly regular behaviors observed for a class 4 cellular automaton, the totalistic rule 20: starting from disordered initial configurations the automaton produces patterns which are periodic not only in time but also in space. This is the first evidence that different types of spatio-temporal order can emerge under specific conditions out of disorder in the same discrete rule based algorithm.Comment: 5 pages, 6 color figures, Proceedings Medyfinol 2004, Physica A in prin

Naimark-Sacker Bifurcations in Linearly Coupled Quadratic Maps

We report exact analytical expressions locating the $0\to1$, $1\to2$ and $2\to4$ bifurcation curves for a prototypical system of two linearly coupled quadratic maps. Of interest is the precise location of the parameter sets where Naimark-Sacker bifurcations occur, starting from a non-diagonal period-2 orbit. This result is the key to understand the onset of synchronization in networks of quadratic maps.Comment: 6 pages, 3 figures (1 in color), submitted to Physica

Complexity in subnetworks of a peroxidase-oxidase reaction model

The peroxidase-oxidase (PO) reaction is a paradigmatic (bio)chemical system well suited to study the organization and stability of self-sustained oscillatory phases typically present in nonlinear systems. The PO reaction can be simulated by the state-of-the-art Bronnikova-Fedkina-Schaffer-Olsen model involving ten coupled ordinary differential equations. The complex and dynamically rich distribution of self-sustained oscillatory stability phases of this model was recently investigated in detail. However, would it be possible to understand aspects of such a complex model using much simpler models? Here, we investigate stability phases predicted by three simple four-variable subnetworks derived from the complete model. While stability diagrams for such subnetworks are found to be distorted compared to those of the complete model, we find them to surprisingly preserve significant features of the original model as well as from the experimental system, e.g., period-doubling and period-adding scenarios. In addition, return maps obtained from the subnetworks look very similar to maps obtained in the experimental system under different conditions. Finally, two of the three subnetwork models are found to exhibit quint points, i.e., recently reported singular points where five distinct stability phases coalesce. We also provide experimental evidence that such quint points are present in the PO reaction. </p

The Nature of a Passport at the Intersection of Customary International Law and American Judicial Practice

In order to fully develop the argument that the DHS’s confiscation and impoundment of passports is a violation of customary international law, we begin by examining the history of a passport and its treatment in the international community. Next, we survey general principles of customary international law and analyze German case law holding that one State’s confiscation or impounding of a valid foreign passport constitutes an encroachment upon the passport jurisdiction of the foreign State issuing the documents which is impermissible under customary international law. Thereafter, we discuss case law where courts avoided addressing the international implications of passport seizures. We then examine the United States government’s view of passports by tracking the shift in its behavior from adhering to international norms to placing domestic prerogatives over customary international law. In doing so, we survey United States law pertaining to confiscation of passports. We conclude that the United States government’s impounding of a foreign passport violates general principles of customary international law because the United States government’s act of impounding a foreign passport is an encroachment upon the personal jurisdiction of the issuing State. However, we acknowledge that the rationale behind the DHS’s continued practice of impounding passports in violation of customary international law suggests that the United States government believes ensuring the return of the foreign national is more important than a State’s personal jurisdiction over its property. Accordingly, we recommend that the United States codify the authority, means, and methods by which such impounding can be carried out in order to avoid international retaliation

The Legacy of Operation Allied Force: A Reflection on its Legality Under United States and International Law

Article published in the Michigan State International Law Review

The Nature of a Passport at the Intersection of Customary International Law and American Judicial Practice

In order to fully develop the argument that the DHS’s confiscation and impoundment of passports is a violation of customary international law, we begin by examining the history of a passport and its treatment in the international community. Next, we survey general principles of customary international law and analyze German case law holding that one State’s confiscation or impounding of a valid foreign passport constitutes an encroachment upon the passport jurisdiction of the foreign State issuing the documents which is impermissible under customary international law. Thereafter, we discuss case law where courts avoided addressing the international implications of passport seizures. We then examine the United States government’s view of passports by tracking the shift in its behavior from adhering to international norms to placing domestic prerogatives over customary international law. In doing so, we survey United States law pertaining to confiscation of passports. We conclude that the United States government’s impounding of a foreign passport violates general principles of customary international law because the United States government’s act of impounding a foreign passport is an encroachment upon the personal jurisdiction of the issuing State. However, we acknowledge that the rationale behind the DHS’s continued practice of impounding passports in violation of customary international law suggests that the United States government believes ensuring the return of the foreign national is more important than a State’s personal jurisdiction over its property. Accordingly, we recommend that the United States codify the authority, means, and methods by which such impounding can be carried out in order to avoid international retaliation

Dendritic cell immunotherapy followed by cART interruption during HIV-1 infection induces plasma protein markers of cellular immunity and neutrophil recruitment

Objectives To characterize the host response to dendritic cell-based immunotherapy and subsequent combined antiretroviral therapy (cART) interruption in HIV-1-infected individuals at the plasma protein level. Design An autologous dendritic cell (DC) therapeutic vaccine was administered to HIV-infected individuals, stable on cART. The effect of vaccination was evaluated at the plasma protein level during the period preceding cART interruption, during analytical therapy interruption and at viral reactivation. Healthy controls and post-exposure prophylactically treated healthy individuals were included as controls. Methods Plasma marker (‘analyte’) levels including cytokines, chemokines, growth factors, and hormones were measured in trial participants and control plasma samples using a multiplex immunoassay. Analyte levels were analysed using principle component analysis, cluster analysis and limma. Blood neutrophil counts were analysed using linear regression. Results Plasma analyte levels of HIV-infected individuals are markedly different from those of healthy controls and HIV-negative individuals receiving post-exposure prophylaxis. Viral reactivation following cART interruption also affects multiple analytes, but cART interruption itself only has only a minor effect. We find that Thyroxine-Binding Globulin (TBG) levels and late-stage neutrophil numbers correlate with the time off cART after DC vaccination. Furthermore, analysis shows that cART alters several regulators of blood glucose levels, including C-peptide, chromogranin-A and leptin. HIV reactivation is associated with the upregulation of CXCR

Equity lending markets and ownership structure

Using proprietary data on equity lending supply, loan fees and quantities, we examine the link between institutional ownership structure and the market for equity lending and stock prices. We find that both total institutional ownership and ownership concentration (measured by the Herfindahl index, single largest holding and number of investors) are important determinants of equity lending supply and short sale constraints. More concentrated ownership structures increase short sale constraints (including loan fees, recall risk and arbitrage risk) and force arbitrageurs to decrease demand for equity borrowing and demand greater compensation for borrowing stock. The results suggest that the impact of institutional ownership structure in the equity lending market may create limits to arbitrage.Equity lending markets; short selling; ownership structure; lending supply;

Complexity of a Peroxidase-Oxidase Reaction Model

The peroxidase-oxidase oscillating reaction was the first (bio)chemical reaction to show chaotic behaviour. The reaction is rich in bifurcation scenarios, from period-doubling to peak-adding mixed mode oscillations. Here, we study a state-of-the-art model of the peroxidase-oxidase reaction. Using the model, we report systematic numerical experiments exploring the impact of changing the enzyme concentration on the dynamics of the reaction. Specifically, we report high-resolution phase diagrams predicting and describing how the reaction unfolds over a quite extended range of enzyme concentrations. Surprisingly, such diagrams reveal that the enzyme concentration has a huge impact on the reaction evolution. The highly intricate dynamical behaviours predicted here are difficult to establish theoretically due to the total absence of an adequate framework to solve nonlinearly coupled differential equations. But such behaviours may be validated experimentally.</p