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Complementary shifts in photoreceptor spectral tuning unlock the full adaptive potential of ultraviolet vision in birds

Color vision in birds is mediated by four types of cone photoreceptors whose maximal sensitivities (λmax) are evenly spaced across the light spectrum. In the course of avian evolution, the λmax of the most shortwave-sensitive cone, SWS1, has switched between violet (λmax > 400 nm) and ultraviolet (λmax < 380 nm) multiple times. This shift of the SWS1 opsin is accompanied by a corresponding short-w

System simulations of a 1.5 V SiGe 81-86 GHz E-band transmitter

This paper presents simulation results for a sliding-IF SiGe E-band transmitter circuit for the 81-86 GHz E-band. The circuit was designed in a SiGe process with fT = 200 GHz and uses a supply of 1.5 V. The low supply voltage eliminates the need for a dedicated transmitter voltage regulator. The carrier generation is based on a 28 GHz quadrature voltage oscillator (QVCO). Upconversion to 84 GHz is

From Demonstrations to Skills for High-level Programming of Industrial Robots

In this paper we describe our approach to robotic skill representation and a prototypical implementation of a programming-by-demonstration approach that allows users to generate skills and robot program primitives for later re- finement and re-use. We intend to evaluate the applicability of this approach to high-level programming in a user study, which we also explain.

Recent developments in the ABINIT software package

ABINIT is a package whose main program allows one to find the total energy, charge density, electronic structure and many other properties of systems made of electrons and nuclei, (molecules and periodic solids) within Density Functional Theory (DFT), Many-Body Perturbation Theory (GW approximation and Bethe-Salpeter equation) and Dynamical Mean Field Theory (DMFT). ABINIT also allows to optimize

Mariyamma and the logic of realist explanation in sociology

Realism as a theory of science, in the view of the author of this paper, provides elegant solutions to several puzzles and dilemmas, not only in philosophy, but also to some of the most fundamental theorerical and methodological problems in social science. This paper introduces scien­tific realism, and presents one way of applying it to social science.

Housing in an enriched environment : A tool to study functional recovery after experimental stroke

Physical therapy and social interactions between the stroke patient and health-care professionals or relatives facilitate the process of recovery and promote improvement of lost neurological function after stroke. These observations can be mimicked in an experimental setting by multimodal stimulation provided in the concept of enriched environment. The enriched environment is a housing condition f

Gephyrin Cleavage in In Vitro Brain Ischemia Decreases GABAA Receptor Clustering and Contributes to Neuronal Death

GABA (γ-aminobutyric acid) is the major inhibitory neurotransmitter in the central nervous system, and changes in GABAergic neurotransmission modulate the activity of neuronal networks. Gephyrin is a scaffold protein responsible for the traffic and synaptic anchoring of GABAA receptors (GABAAR); therefore, changes in gephyrin expression and oligomerization may affect the activity of GABAergic syna

Bäckaskog - a Norbertine Abbey in the Circary of Denmark and Norway

In the twelfth century the Norbertine order was introduced in parts of Scandinavia. One initiator in the north was Eskil, the powerful archbishop of Lund. However, in the beginning of the thirteenth century the mendicant orders were introduced by successors to the archbishopric. This led to a general decline of other orders. In spite of that the Norbertines managed to prosper in Bäckaskog, an abbeIn the twelfth century the Norbertine order was introduced in parts of Scandinavia. One initiator in the north was Eskil, the powerful archbishop of Lund. However, in the beginning of the thirteenth century the mendicant orders were introduced by successors to the archbishopric. This led to a general decline of other orders. In spite of that the Norbertines managed to prosper in Bäckaskog, an abbe