Shadows in Coxeter groups

For a given $w$ in a Coxeter group $W$ the elements $u$ smaller than $w$ in Bruhat order can be seen as the end-alcoves of stammering galleries of type $w$ in the Coxeter complex $\Sigma$. We generalize this notion and consider sets of end-alcoves of galleries that are positively folded with respect to certain orientation $\phi$ of $\Sigma$. We call these sets shadows. Positively folded galleries are closely related to the geometric study of affine Deligne-Lusztig varieties, MV polytopes, Hall-Littlewood polynomials and many more agebraic structures. In this paper we will introduce various notions of orientations and hence shadows and study some of their algorithmic properties.Comment: 30 pages, 8 figures, revised and final versio

Tax return as a political statement

The accuracy of a tax return is usually interpreted as an outcome of the tax evasion decision by an individual. However, in non-democratic regimes with predatory blackmail tax systems it is possible that large sums voluntarily reported by influential politicians or businessmen may be used as political statements. By openly acknowledging one's personal income an individual can signal the strength of one's position, or, on the contrary, the submissiveness to the political leadership. In this paper we explore the idea of the tax return as a political statement and test it using a unique dataset of the tax returns filed by the Russian regional governors and the members of their families for the year 2009. Our results conjecture that Russian governors may deliberately file their tax return as a political statement to signal their strength vis-à-vis the central government. --tax compliance,communication in non-democracies,Russian regions

Cascade Freezing of Supercooled Water Droplet Collectives

Surface icing affects the safety and performance of numerous processes in technology. Previous studies mostly investigated freezing of individual droplets. The interaction among multiple droplets during freezing is investigated less, especially on nanotextured icephobic surfaces, despite its practical importance as water droplets never appear in isolation, but in groups. Here we show that freezing of a supercooled droplet leads to spontaneous self-heating and induces strong vaporization. The resulting, rapidly propagating vapor front causes immediate cascading freezing of neighboring supercooled droplets upon reaching them. We put forth the explanation that, as the vapor approaches cold neighboring droplets, it can lead to local supersaturation and formation of airborne microscopic ice crystals, which act as freezing nucleation sites. The sequential triggering and propagation of this mechanism results in the rapid freezing of an entire droplet ensemble resulting in ice coverage of the nanotextured surface. Although cascade freezing is observed in a low-pressure environment, it introduces an unexpected pathway of freezing propagation that can be crucial for the performance of rationally designed icephobic surfaces

Radical alterity is just another way of saying “reality”: a reply to Eduardo Viveiros de Castro

As a response to Eduardo Viveiros de Castro’s critique of my essay “Fetishes are gods in the process of construction,” this paper enters into critical engagement with anthropological proponents of what has been called the “ontological turn.” Among other engagements, I note that my own reflections on Malagasy fanafody, or medicine, are informed by just the sort of self-conscious reflections my informants make on epistemology, something that anthropologists typically ignore. After making note of the arguments of Roy Bhaskar that most post-Cartesian philosophy rests on an “epistemic fallacy,” I further argue that a realist ontology, combined with broad theoretical relativism, is a more compelling political position than the “ontological anarchy” and theoretical intolerance of ontological turn exponents

Reflections on reflections

Comment on Ortner, Sherry. 2016. “Dark anthropology and its others: Theory since the eighties.” Hau: Journal of Ethnographic Theory 6 (1): 47–73

Mobility and Citizenship in the Shadow of the Euro Crisis: Explaining New Trends in Immigration and Naturalization across Europe

Austerity, slow growth, rising unemployment have had worrying effects on the countries of the European Union in the aftermath of the Euro crisis. Fears of the Eurozone’s demise, although somewhat abated for the moment, continue to bring political and economic uncertainty to citizens and governments across the continent. One relatively unexplored consequence of the Euro crisis and the uncertainty it has engendered has been the new changes in mobility and citizenship acquisition trends within the EU. During periods of economic crisis, immigrants often find themselves pushed across borders by slow growth and high unemployment at home in search of better economic opportunities that pull them abroad. During the Euro crisis, while governments have been restricting flows of third-­‐country nationals within Europe in general, many Europeans have taken advantage mobility rights within the Schengen area and have gone in search of better opportunities elsewhere in the EU. For many, the economic benefits of mobility are alluring. However, new evidence suggests that the Euro crisis is increasing the economic benefits of citizenship acquisition as well, prompting new trends in naturalization across a growing number of countries. How has the crisis affected immigration and naturalization trends across Europe in its aftermath

Web-based relay management with biometric authentication

This thesis proposes a web-based system for managing digital relay settings. These relays are deployed in the power system to protect sensitive and expensive equipment from physical damage during system faults and overload conditions. Providing this capability exposes these devices to the same cyber security threats that corporations have faced for many years.;This thesis investigates the risks and requirements for deploying the proposed system. A breakdown in the protection that these relays provide would cause power outages. The cost of outages can be significant. Therefore cyber security is critical in the system design. Cyber security requirements for the power industry identify access control as an important aspect for the protection of its infrastructure. If properly implemented, biometrics can be used to strengthen access control to computer systems.;The web-based relay management system uses fingerprint authentication along with a username and password to provide access control. Website users are given access to functionality based on user roles. Only high level users may attempt relay setting modification. The relay management system interacts with a database that stores the current relay settings, relay setting restrictions, and a queue of relay updates. A process is implemented to verify attempted setting changes against these setting restrictions. This provides an extra security layer if users attempt harmful changes to protection schemes. Valid setting changes are added to the queue and a separate relay update program communicates these changes to the relay. The database and relay update program protect the relays from direct modification. These features combined with biometric authentication provide a strong layered scheme for protecting relays, while supplying an easy to use interface for remotely using their capabilities

A linear mixed model approach to gene expression-tumor aneuploidy association studies.

Aneuploidy, defined as abnormal chromosome number or somatic DNA copy number, is a characteristic of many aggressive tumors and is thought to drive tumorigenesis. Gene expression-aneuploidy association studies have previously been conducted to explore cellular mechanisms associated with aneuploidy. However, in an observational setting, gene expression is influenced by many factors that can act as confounders between gene expression and aneuploidy, leading to spurious correlations between the two variables. These factors include known confounders such as sample purity or batch effect, as well as gene co-regulation which induces correlations between the expression of causal genes and non-causal genes. We use a linear mixed-effects model (LMM) to account for confounding effects of tumor purity and gene co-regulation on gene expression-aneuploidy associations. When applied to patient tumor data across diverse tumor types, we observe that the LMM both accounts for the impact of purity on aneuploidy measurements and identifies a new association between histone gene expression and aneuploidy