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A study was made on the penetration and cellular uptake of two protein tracers, albumin labelled with Evans blue (EBA) and horseradish peroxidase (HP), in the nervous system of the crayfish following systemic and local administration. Followingsystemic injection, EBA did not diffuse freely from the cerebral vessels into the brain parenchyma. When the tracers werelocally applied on the surface of t

The ultrastructure of the paired nerves, previously called frontal organ or X-organ, in copepod crustaceans was investigated. These nerves, run- ning from the anterior margin of the brain to the frontal edge of the animals, are found to contain the dendrites of three types of morpho- logically different sensory neurons. The first unit consists of two dendrites (distinguished by their myelinization

The cavity receptor organ (previously X-organ or organ of Bellonci) of Artemia salina consists of ciliated neurons whose cilia protrude into a cavity beneath the cuticle. The neuronal dendrites penetrate a giant accompanying cell and epidermal cells before entering the cavity. The cavity beneath the cuticle, the ciliated neurons and the connexion with the medulla terminalis justifies a homologizatThe cavity receptor organ (previously X-organ or organ of Bellonci) of Artemia salina consists of ciliated neurons whose cilia protrude into a cavity beneath the cuticle. The neuronal dendrites penetrate a giant accompanying cell and epidermal cells before entering the cavity. The cavity beneath the cuticle, the ciliated neurons and the connexion with the medulla terminalis justifies a homologizat

The ultrastructure of the chromatophores of two decapod crustaceans, Crangon crangon and Pandalus borealis, is investigated. The pigment appears macroscopically as small units, so-called chromatosomes. These contain separate chromatophores of different colors, and each color is composed of several chromatophores. Each chromatophore contains pigment granules, tubuli (ca. 210 Å), a network of cister

The internal morphology of the crustacean larval form that Hansen (1899) called nauplius y has revealed a remarkably advanced early nauplius. The nervous system is well developed and differentiated. It is connected with the anlagen of the compound eyes. A presumed filamentous base of the SPX-organ connects with these. The nauplius eye is present in a three-partite form with two retinula cells in e

A new photoreceptor in the Copepoda is described. The organ, previously called Gicklhorn's organ (Elofsson, 1966a), is paired and is usually situated beneath the cuticle of the front. Each member of the pair consists of two cells. From the anterolateral position, two nerves lead to the lateral part of the brain. No connexion with the nauplius eye is found. Each cell of the organ has microvilli, tw

On the basis of ontogeny and adult morphology, an interpretation of the arrangement of optic neuropiles and fibre connexions of the Crustacean compound eye is presented. In the embryo of phyllopods and decapods, the ommatidia, the lamina ganglionaris, and the medulla externa are developed synchronously from a common medial proliferation zone. As this zone persists in all investigated adult Crustac

The brain, the compound eyes and the ocelli are described for some zygentomid species. Special interest has been focused on Tricholepidion gertschii, a newly discovered, primitive species. The brain morphology shows great similarities in the general shape and in details within the whole suborder. The compound eyes of Tricholepidion gertschii and Lepisma saccharina resemble each other closely. The

The ultrastructure of the specialized nauplius eye of three species of the copepod genusSapphirina was investigated. The gross morphology described earlier (Elofsson, 1966a) was confirmed. The ventral cup is covered by a red pigment and the lateral cups by a red and a black pigment. The ultrastructural configuration of the pigment granules was found to differ in the two kinds of pigment cells. The

The development of the compound eyes and nervous system of the penaeid shrimp,Penaeus duorarum, from the first nauplius to the first postlarva, has been studied. The first anlage of the compound eyes is a pair of optic discs on the front of the animal. These increase in size through cell-division until the second protozoea stage, where the eye-stalks appear with ommatidia and optic neuropiles deve

Whereas the characterization of B lymphoid progenitors has been facilitated by the identification of lineage-and stage-specific surface markers, the continued identification of differentially expressed proteins increases our capacity to explore normal and malignant B cell development. To identify novel surface markers with stage-specific expression patterns, we explored the reactivity of CD19+ B c

In diffusion MRI (dMRI), microscopic diffusion anisotropy can be obscured by orientation dispersion. Separation of these properties is of high importance, since it could allow dMRI to non-invasively probe elongated structures such as neurites (axons and dendrites). However, conventional dMRI, based on single diffusion encoding (SDE), entangles microscopic anisotropy and orientation dispersion with

Under de senaste tjugo åren har offentlig sektor blivit alltmer präglad av New Public Management (NPM). Såväl beskrivningar som konkretiseringar av NPM varierar men två drag återkommer som gemensam nämnare; dels att offentlig sektor har närmat sig den privata i sättet att styra och organisera verksamheten, dels att betoningen har skiftat från ansvar för processer till ansvar för resultat.Med resul

The debate surrounding the challenge of improving coherence in European Union (EU) foreign policy is ongoing. EU Delegations (EUDs), operating under the European External Action Service (EEAS) were recently established to provide a focal point for the EU in third countries, providing potential for improving EU coherence. Using the case study of the EUDs, this article adds to theorizations of EU co

This paper presents a novel approach for the elaboration of an integration strategy for controls and computing systems at large particle accelerator based research facilities. The approach is applied in a specific case study conducted at the world-leading neutron science facility European Spallation Source (ESS). First, an introduction to the term 'integration' in the Systems Engineering literatur