How Europe’s history of interstate rivalry is linked to global imperialism – and why it still matters today

What were the origins of European imperialism? Drawing on a new study, Jan P. Vogler explains that centuries of European interstate rivalries were an essential contributor to historical imperial expansion by the continent’s major powers. He outlines three mechanisms that link interstate competition to colonial expansion and illustrates them through two historical cases

Economic elites and the constitutional design of sharing political power

What explains the emergence and persistence of institutions aimed at preventing any ruling group from using the state apparatus to advance particularistic interests? To answer this recurring question, a burgeoning literature examines the establishment of power-sharing institutions in societies divided by ethnic or religious cleavages. Going beyond existing scholarly work focused on these specific settings, we argue that political power-sharing institutions can also be the result of common disputes within the economic elite. We propose that these institutions are likely to emerge and persist when competition between elite factions with dissimilar economic interests is balanced. To address the possibility of endogeneity between elite configurations and public institutions, we leverage natural resource diversity as an instrument for elite configurations. We show that, where geological resources are more diverse, competition between similarly powerful economic groups is more likely to emerge, leading ultimately to the establishment of power-sharing mechanisms that allow elite groups to protect their diverging economic interests

How the European Union’s structural funds helped promote a key aspect of democratisation

Can EU funding increase local state capacity? Paweł Charasz and Jan P. Vogler present results from a randomised survey of more than 2,400 municipal administrations in Poland. They find that local governments that have strongly benefited from EU funding exhibit more efficient internal administrative decision-making. When the Soviet Empire disintegrated, a challenge of monumental proportions ... Continue

Non-self-embedding linear context-free tree grammars generate regular tree languages

For the class of linear context-free tree grammars, we define a decidable property called self-embedding. We prove that each non-self-embedding grammar in this class generates a regular tree language and show how to construct the equivalent regular tree grammar.PostprintPeer reviewe

Hybrid grammars for parsing of discontinuous phrase structures and non-projective dependency structures

We explore the concept of hybrid grammars, which formalize and generalize a range of existing frameworks for dealing with discontinuous syntactic structures. Covered are both discontinuous phrase structures and non-projective dependency structures. Technically, hybrid grammars are related to synchronous grammars, where one grammar component generates linear structures and another generates hierarchical structures. By coupling lexical elements of both components together, discontinuous structures result. Several types of hybrid grammars are characterized. We also discuss grammar induction from treebanks. The main advantage over existing frameworks is the ability of hybrid grammars to separate discontinuity of the desired structures from time complexity of parsing. This permits exploration of a large variety of parsing algorithms for discontinuous structures, with different properties. This is confirmed by the reported experimental results, which show a wide variety of running time, accuracy and frequency of parse failures.Publisher PDFPeer reviewe

Regular transductions with MCFG input syntax

We show that regular transductions for which the input part is generated by some multiple context-free grammar can be simulated by synchronous multiple context-free grammars. We prove that synchronous multiple context-free grammars are strictly more powerful than this combination of regular transductions and multiple context-free grammars.Publisher PD

Quantification of mechanical forces and physiological processes involved in pollen tube growth using microfluidics and microrobotics

Pollen tubes face many obstacles on their way to the ovule. They have to decide whether to navigate around cells or penetrate the cell wall and grow through it or even within it. Besides chemical sensing, which directs the pollen tubes on their path to the ovule, this involves mechanosensing to determine the optimal strategy in specific situations. Mechanical cues then need to be translated into physiological signals, which eventually lead to changes in the growth behavior of the pollen tube. To study these events, we have developed a system to directly quantify the forces involved in pollen tube navigation. We combined a lab-on-a-chip device with a microelectromechanical systems-based force sensor to mimic the pollen tube's journey from stigma to ovary in vitro. A force-sensing plate creates a mechanical obstacle for the pollen tube to either circumvent or attempt to penetrate while measuring the involved forces in real time. The change of growth behavior and intracellular signaling activities can be observed with a fluorescence microscope

Long-term experimental study of price responsive predictive control in a real occupied single-family house with heat pump

The continuous introduction of renewable electricity and increased consumption through electrification of the transport and heating sector challenges grid stability. This study investigates load shifting through demand side management as a solution. We present a four-month experimental study of a low-complexity, hierarchical Model Predictive Control approach for demand side management in a near-zero emission occupied single-family house in Denmark. The control algorithm uses a price signal, weather forecast, a single-zone building model, and a non-linear heat pump efficiency model to generate a space-heating schedule. The weather-compensated, commercial heat pump is made to act smart grid-ready through outdoor temperature input override to enable heat boosting and forced stops to accommodate the heating schedule. The cost reduction from the controller ranged from 2-33% depending on the chosen comfort level. The experiment demonstrates that load shifting is feasible and cost-effective, even without energy storage, and that the current price scheme provides an incentive for Danish end-consumers to shift heating loads. However, issues related to controlling the heat pump through input-manipulation were identified, and the authors propose a more promising path forward involving coordination with manufacturers and regulators to make commercial heat pumps truly smart grid-ready