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A functional analysis of compound eye evolution.

New data on the phylogenetic relationships of various arthropod groups have spurred interesting attempts to reconstruct the evolution of arthropod nervous and visual systems. Some of the relevant new data are cell identities and developmental processes in the nervous and sensory systems, which is particularly useful for reconstructing the evolution of these systems. Here, we focus on the structure

Refined myoelectric control in below-elbow amputees using artificial neural networks and data glove

Purpose: To develop a system for refined motor control of artificial hands based on multiple electromyographic (EMG) recordings, allowing multiple patterns of hand movements. Methods: Five subjects with traumatic below-elbow amputations and 1 subject with a congenital below-elbow failure of formation performed 10 imaginary movements with their phantom hand while surface electrodes recorded the EMG

Detection and prevention of hepatitis C in dialysis patients and renal transplant recipients. A long-term follow up (1989-january 1997)

Background. Hepatitis C is frequent problem in dialysis wards. Design. A long time (1989-97) follow up of hepatitis C virus (HCV) infection in a Swedish nephrology unit was performed with anti-HCV screening, confirmatory antibody tests, viral RNA detection and molecular characterization. Case histories were reviewed with focus, onset of infection, liver morbidity and mortality. Results. In October

Structure and activity of the bacterial community in the rhizosphere of different plant species and the effect of arbuscular mycorrhizal colonisation

The aim of this study was to determine if arbuscular mycorrhizal (AM) colonisation influences rhizosphere bacteria differently depending on plant species. Thus, the effect of AM colonisation (Glomus intraradices) on rhizosphere bacteria of subterranean clover, cucumber, leek and maize was studied. The bacterial activity was measured as thymidine or leucine incorporation and bacterial numbers as co

Kapitalbildning i svensk industri 1870-1930

Popular Abstract in Swedish Betydelsen av fysiskt kapital är något som ofta understryks i allmänna ordalag i den ekonomisk-historiska litteraturen. Väldigt få undersökningar har däremot försökt att kvantifiera och analysera det fysiska kapitalets betydelse för ekonomisk tillväxt under den svenska industrialiseringsprocessen. Det gäller i synnerhet på branschnivå. En sådan studie genomförs därför iThe significance of physical capital is often mentioned in general terms in economic history literature. In this study the amount of physical capital is calculated and its significance for industrial growth is analysed for the period 1870-1930. The largest and most important part of this thesis consists of constructions of capital stocks for industry as a whole and on the branch level. These cons

Heterointerfaces in III-V semiconductor nanowhiskers

We have investigated heterostructures formed within Vapor-Liquid-Solid grown III-V nanowhiskers. The growth conditions that are typical for chemical beam epitaxy facilitate the creation of atomically abrupt interfaces. In this paper we investigate the properties of heterostructure interfaces including switching of either the column-V material (As, P) or the column-III material (In, Ga).

Relationship of airway responsiveness to agents causing bronchoconstriction and cough in sensitized guinea-pigs

The relationship between airway responsiveness to bronchoconstrictor- and cough-inducing stimuli has been examined in Ascaris suum-sensitized conscious guinea-pigs. Guinea-pigs were sensitized to Ascaris suum [4000 PNU and 100 mg Al(OH)3 i.p. on days 1 and 7] and then challenged with aerosolized antigen on days 21, 28 and 35. At day 35, antigen-exposure produced an early bronchoconstrictor respons

Binuclear ruthenium-manganese complexes as simple artificial models for photosystem II in green plants

As part of a project aimed at developing models for photosystem II (PSII) in green plants, we have prepared a series of model compounds (7, 8, and 13). In these compounds, a photosensitizer, ruthenium(II) tris(bipyridyl) complex (to mimic the function of P-680 in PSII), was covalently linked to a manganese(II) ion through different bridging ligands. The structures of the compounds were characteriz