MreB helical pitch angle determines cell diameter in Escherichia coli

Bacteria have remarkably robust cell shape control mechanisms. For example, cell diameter only varies by a few percent across a population. MreB is necessary for establishment and maintenance of rod shape although the mechanism of shape control remains unknown. We perturbed MreB in two complimentary ways to produce steady-state cell diameters over a wide range, from 790+/-30 nm to 1700+/-20 nm. To determine which properties of MreB are important for diameter control, we correlated structural characteristics of fluorescently-tagged MreB polymers with cell diameter by simultaneously analyzing 3-dimensional images of MreB and cell shape. Our results indicate that the pitch angle of MreB inversely correlates with cell diameter. Other correlations are not found to be significant. These results demonstrate that the physical properties of MreB filaments are important for shape control and support a model in which MreB dictates cell diameter and organizes cell wall growth to produce a chiral cell wall

Ernst Freund as Precursor of the Rational Study of Corporate Law

Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe

Ethnic Party Bans in East Africa from a Comparative Perspective

Since 1990 the banning of ethnic and other identity-based parties has become the norm in sub-Saharan Africa. This article focuses on Kenya, Tanzania and Uganda as three East African countries that have opted for different ways of dealing with such parties. Using case studies, it traces the origins of the party bans in Tanzania and Uganda and explores the reasons for the absence of a ban in Kenya. The analysis shows that the laws on particularistic parties have actually been implemented by the appropriate institutions. However, these laws have only marginally influenced the character of the political parties in the three countries: A comparison of regional voting patterns suggests that bans on particularistic parties have not ensured the emergence of aggregative parties with a national following in Tanzania and Uganda. In Kenya on the other hand, where such a ban was nonexistent until 2008, parties have not proven to be more regional.Das Verbot ethnischer und anderer identitätsbasierter politischer Parteien ist seit Beginn der 1990er Jahre im subsaharischen Afrika zur Norm geworden. Der vorliegende Aufsatz analysiert drei ostafrikanische Länder, die verschiedene Wege im Umgang mit partikularistischen Parteien eingeschlagen haben und untersucht, warum Tansania und Uganda ein Parteienverbot eingeführt haben, Kenia jedoch nicht. Die Untersuchung macht zudem deutlich, dass die zuständigen Institutionen die Gesetze zwar anwenden, dies jedoch nicht zu nationalen Parteien führt: Eine Analyse der Wahlergebnisse auf subnationaler Ebene zeigt, dass insbesondere Oppositionsparteien oft regionale Hochburgen aber keine landesweite Unterstützung haben. Politische Parteien in Kenia sind dabei trotz divergierender Parteiregulierung nicht deutlich weniger national als Parteien in Tansania und Uganda

Origins and Outcomes of Electoral Institutions in African Hybrid Regimes: A Comparative Perspective

In the early 1990s most African countries carried out extensive reforms of their electoral regimes. Adopting a historical institutionalist approach, this paper critically examines the role of institutional path dependence in accounting for the setup of six African electoral regimes. For this purpose, we distinguish between different types of path dependence. The paper further analyzes the extent to which the development of electoral institutions contributed to the regime-type outcome (democratic/hybrid/autocratic). The main emphasis herein is on so-called hybrid regimes; in other words, regimes existing in the grey zone between democracy and autocracy. The paper finds that, while institutional path dependence has a limited but important impact on the setup of the electoral regimes, it is ultimately the process of decision-making during critical junctures that accounts for the regime type outcome. Hybrid regimes lack long-term institutional ownership

On anthropolysis. Trans. Jakub Wolak

Kiedy Hegel usiłował powiązać historię świata z historią europejskich tożsamości narodowych, jego słuchacze zakładali, że miarą wieku ziemi są tysiąclecia (103 lub 104 lat), a nie eony (109 lat). Fabrykacja pamięci narodowej miała dotyczyć podobnego horyzontu czasowego co dzieje planety, a obydwa procesy postrzegano jako wzajemnie zbieżne naturalne cykle. I choć paleogenetyka i geologia wyraźnie temu przeczą, iluzja współmierności chronologii gatunkowej i planetarnej przyniosła opłakane skutki, które, jak na ironię, doprowadziły do jej urzeczywistnienia. Ową metakonsekwencją jest antropocen, epoka w której lokalna historia gospodarcza faktycznie zaważyła na obliczu planety, kształtując je na swój obraz i podobieństwo. Chronologiczne zestrojenie człowieka i planety okazało się zatem samospełniającym się przesądem. Czym wobec tego różnią się, a w czym są sobie podobni ánthrōpos antropogenezy i ánthrōpos antropocenu? Czy odpowiadają sobie nawzajem? Czy pojawienie się człowieka musi bezwarunkowo skutkować antropocenem? A jeśli nie musi prowadzić do tego partykularnego współczesnego nam antropocenu, to czy nie skutkuje antropocenem w najszerszym tego słowa znaczeniu, a zatem sztywnym zespoleniem ekonomii społecznych i geologicznych?When Hegel was binding the history of the world to the history of European national self-identity, it was assumed among his public that the age of the planet could be measured in a few millennia (1e3 or 1e4 years), not aeons (1e9 years). The fabrication of social memory and the intuition of planetary duration were thought to operate in closely-paired natural rhythms. While the deep time of the genomic and geologic record shows that that they do not, the illusion of their contemporaneity also brought dark consequences that, strangely enough, would actualize that exact same illusion. In the subsequent era, the meta-consequence of this short-sighted conceit is the Anthropocene itself, a period in which local economic history has in fact determined planetary circumstances in its own image. The temporal binding of social and planetary time has been, in this way, a self-fulfilling superstition. As such, how is the anthropos of Anthropogeny similar to or different from the anthropos of the Anthropocene? Are they correspondent? Does the appearance of the human lead inevitably toward, if not this particular Anthropocene, then an Anthropocene, and some eventual strong binding of social and geologic economies

Le Stack à venir

Les secrets sont des mensonges.Le Cercle, « Politique de l’entreprise » La surveillance est un vol.Writers Against Mass Surveillance L’autonomie est une abstraction.Chris Anderson, 3D Robotics Le confort signifie que la sécurité n’est pas assurée.Jacob Appelbaum, projet Tor La peur n’est rien d’autre que la conscience.Charles Manson 16. Voir le Stack-que-nous-avons et les Stacks à venir Le Stack-que-nous-avons signifie : les limites sont récrites, en pointillé, courbes, effacées, automatisées..

Le Stack noir

23. Angelus Novus a disparu Dans quelle mesure le Stack, et son modèle de logiciels et de souverainetés imbriqués et incompatibles, est-il une réponse à l’appel d’Hillary Clinton à une architecture géopolitique alternative ? Ou est-il une réponse à une autre question, à une meilleure question ? Pour notre géodesign séculier, le flou par lequel le Stack-que-nous-avons devient le Stack-à-venir n’offre aucune rédemption historique et messianique ; ce n’est la « communauté qui vient » de personne..

Introduction

1. Une nouvelle architecture ? Dans un discours prononcé au Council on Foreign Relations sur la nécessité d’une nouvelle architecture géopolitique, la secrétaire d’État sortante Hillary Clinton a formulé une recommandation assez frappante : « Nous avons besoin d’une nouvelle architecture pour ce nouveau monde, plus proche de Frank Gehry que des anciens Grecs. » Elle décrivait le système dominé par l’Organisation des Nations unies, l’Organisation du traité de l’Atlantique nord et plusieurs aut..