Symmetry-induced giant vortex state in a superconducting Pb film with a fivefold Penrose array of magnetic pinning centers.

A direct visualization of the flux distribution in a Pb film covering a fivefold Penrose array of Co dots is obtained by mapping the local field distribution with a scanning Hall probe microscope. We demonstrate that stable vortex configurations can be found for fields H approximately 0.8H_{1}, H_{1}, and 1.6H_{1}, where H_{1} corresponds to one flux quantum per pinning site. The vortex pattern at 0.8H_{1} corresponds to one vacancy in one of the vertices of the thin tiles, whereas at 1.6H_{1} the vortex structure can be associated with one interstitial vortex inside each thick tile. Strikingly, for H = 1.6H_{1}, interstitial and pinned vortices arrange themselves in ringlike structures ("vortex corrals") which favor the formation of a giant vortex state at their center.

[25 years of forensic psychiatry in the Netherlands, a concise review]. / 25 jaar forensische psychiatrie in Nederland, een beknopt overzicht.

In the past 25 years of forensic psychiatry in the Netherlands, there have been improvements in the quality of information made available for pre-trial assessments, changes in the psychopathological characteristics of the patient population, shifts in the treatment paradigm and an increase in scientific research.

The ultrastructural effect and subcellular localization of mercuric chloride and methylmercuric chloride in insect cells (Aedes albopictusC6/36).

Abstract.The ultrastructural effects of mercuric chloride (Hg) and methylmercuric chloride (MeHg) were studied in theAedes albopictusC6/36 cell line. Both metal salts caused nuclear indentations, chromatin clumping and proliferation of the nucleolus. The mitochondria became pleomorphous. An increase of both free and membrane-bound ribosomes, swelling of the rough endoplasmic reticulum caused by accumulated protein and the appearance of well developed Golgi stacks all indicated the activation of protein synthesis. The activation was probably a cellular response to general stress, and the synthesized proteins may be members of the heat shock protein family. Apart from these common ultrastructural features, Hg-treated cells showed typical clusters of small electron-lucent vacuoles near the Golgi stacks. In cells exposed to MeHg, cytoplasmic tube-like structures were often observed and the disorganization of the organelles together with the appearance of blebs suggested disruption of the microtubules. Mercury accumulation was localized by an autometallographical silver staining technique both at the light and electron microscopic level; silver deposits were quantified by image analysis. For both Hg- and MeHg-treated cells, the degree of silver staining increased rapidly with increasing exposure time, but a considerable heterogeneity within the cell population was found. Lysosomes proved to be the major mercury storage sites in theAedescells and silver deposits could already be found after 30 min of Hg treatment. At sublethal concentrations, Hg inhibited the lysosomal marker enzyme acid phosphatase to some extent. For MeHg, no effect on this enzyme was found.

Diffuse CNS involvement in systemic lupus erythematosus: intrathecal synthesis of the 4th component of complement.

In extracerebral systemic lupus erythematosus (SLE), the complement system plays a prominent pathogenic role, and decreased serum concentration of the 4th component (C4) is a reliable indicator of systemic disease activity. In diffuse CNS-SLE, however, the pathogenic role of complement is less clear. In 12 patients with active diffuse CNS-SLE presenting with delirium (4), organic personality syndrome (3), or generalized seizures (5), we determined the CSF indexes of the complement components C3, C4, and factor B, and of IgG, IgA, and IgM. There was a significant increase of the C4 index in these patients compared with controls and a significantly higher CSF C4 index in patients with an increased IgM index. We conclude that intrathecal C4 is being produced in diffuse CNS-SLE.

Hypomanic behaviour associated with familial spastic paraplegia.

Psychiatric manifestations of familial spastic paraplegia are rare and have been described only infrequently. A 35-year-old male is reported, who presented both hypomanic behaviour and gait disturbances as features of a previously undiagnosed familial spastic paraplegia. This association implies that the CNS manifestations of familial spastic paraplegia may overlap with the neurochemical or neuroanatomic substrata regulating mood.