| 1. |
- Bruhwiler, P, et al.
(författare)
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Vibronic coupling in the photoemission bands of condensed C-60
- 1997
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Ingår i: CHEMICAL PHYSICS LETTERS. - : ELSEVIER SCIENCE BV. - 0009-2614. ; 279:1-2, s. 85-91
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We present photoelectron spectra for the highest occupied molecular orbital (HOMO) of C-60 in the gas phase and a two-dimensional (2D) condensed layer. For low temperatures the similarity in the spectra is striking and places a strict upper limit of 0.07
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| 2. |
- Jankowska, Elzbieta, et al.
(författare)
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A confocal and electron microscopic study of contacts between 5-HT fibres and feline dorsal horn interneurons in pathways from muscle afferents.
- 1997
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Ingår i: The Journal of comparative neurology. - 0021-9967. ; 387:3, s. 430-8
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Tidskriftsartikel (refereegranskat)abstract
- Morphological substrates of actions of serotonin upon dorsal horn interneurons with input from group II muscle afferents were investigated by using two experimental approaches. Twelve interneurons were intracellularly labelled with rhodamine-dextran, and serotoninergic fibres were identified by immunofluorescence. Appositions between the serotoninergic axons and these interneurons were examined with a dual-channel confocal microscope. A further four interneurons were intracellularly labelled with horseradish peroxidase, and serotoninergic axons were identified by immunocytochemistry; these neurons were prepared for combined light and electron microscopy. Confocal microscopy revealed serotoninergic varicosities in apposition to both cell bodies and dendrites. Similar total numbers of appositions were found on the soma, and on dendrites within 100 microm from the soma, on the most completely labelled neurons. The number of appositions on 100-microm segments of dendrites decreased with increasing distances from the soma (from 14.6 within 100 microm, to 3.8 and 2.4 at 100-300 microm, and more than 300 microm distances, respectively). Electron microscopic analysis of two neurons revealed that few of the apparent contacts on cell bodies were synaptic, but, in contrast, many varicosities apposed to proximal dendrites formed synapses. The evidence suggests that serotonin may have more powerful synaptic effects upon the dendrites of this class of dorsal horn interneurons than on their cell bodies.
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| 3. |
- Jankowska, Elzbieta, et al.
(författare)
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Contacts between serotoninergic fibres and dorsal horn spinocerebellar tract neurons in the cat and rat: A confocal microscopic study
- 1995
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Ingår i: Neuroscience. - 0306-4522. ; 67, s. 477-487
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Tidskriftsartikel (refereegranskat)abstract
- Contacts between serotoninergic nerve fibres and dorsal horn dorsal spinocerebellar tract neurons were analysed in order to investigate the morphological basis of actions of serotonin upon dorsal spinocerebellar tract neurons. In a series of experiments dorsal spinocerebellar tract neurons were labelled with intracellularly injected rhodamine-dextran in the cat. The neurons were monosynaptically excited by group II muscle afferents and cutaneous afferents and were identified by antidromic activation following stimuli applied in the cerebellum. In the second series of experiments dorsal spinocerebellar tract neurons were labelled by retrograde transport of Fluorogold injected into the cerebellum in the rat. In both series, serotoninergic fibres were labelled by using a specific anti-serotonin antiserum and were revealed by immunofluorescence. Appositions between the serotoninergic fibres and the cells were inspected with a dual channel confocal microscope. The merged images obtained with the two channels of the microscope were viewed in single optical planes 2 μm apart and in rotated three-dimensional reconstructions. Serotoninergic nerve fibres were found in apposition to cell bodies of all feline dorsal spinocerebellar tract neurons (n = 7) and of 75% of rat dorsal spinocerebellar tract neurons (n = 90). The numbers of putative contacts on cell bodies varied between less than 100 and nearly 300 (mean 160) in the cat and between about five and 30 in the rat. Contacts with dendrites of feline neurons were seen on 96% of 72 dendrites within 300 μm from soma and on 91% of 23 dendrites at distances of 300-500 μm. The number of such contacts varied from less than five to 150 on a single dendrite within these ranges of distances. Their total number within 100 μm from the soma was comparable or exceeded the number of contacts on the soma. © 1995 IBRO.
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| 4. |
- Maxwell, AJ, et al.
(författare)
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C 1s ionisation potential and energy referencing for solid C-60 films on metal surfaces
- 1996
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Ingår i: CHEMICAL PHYSICS LETTERS. - : ELSEVIER SCIENCE BV. - 0009-2614. ; 260:1-2, s. 71-77
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We present a measurement of the C Is ionisation potential (IP) for solid C-60, as well as a reliable determination of the highest occupied molecular orbital (HOMO) IP. The difference between the gas phase and solid state measurements for the HOMO agrees w
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| 5. |
- MAXWELL, AJ, et al.
(författare)
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C-60 ON AL(111) - COVALENT BONDING AND SURFACE RECONSTRUCTION
- 1995
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Ingår i: PHYSICAL REVIEW B-CONDENSED MATTER. - : AMER INST PHYSICS. ; 52:8
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- We present photoemission and C 1s photoabsorption data for an annealed monolayer C-60/Al(111), which show that a strong covalent bond is formed between the C-60 molecules and the substrate. Low-energy electron-diffraction and scanning tunneling microscopy
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| 6. |
- Maxwell, AJ, et al.
(författare)
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Electronic and geometric structure of C-60 on Al(111) and Al(110)
- 1998
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Ingår i: PHYSICAL REVIEW B-CONDENSED MATTER. - : AMERICAN PHYSICAL SOC. - 0163-1829. ; 57:12, s. 7312-7326
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Two new ordered monolayer phases of C-60 on Al surfaces have been studied using electron spectroscopies and low-energy electron diffraction (LEED). On Al(111), in addition to the previously reported (6x6) phase formed by evaporating with T-sample=620 K, a
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| 7. |
- Maxwell, AJ, et al.
(författare)
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Length scales in core level excitation: C 1s x-ray absorption of C-60/Al
- 1997
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Ingår i: PHYSICAL REVIEW LETTERS. - : AMER INST PHYSICS. - 0031-9007. ; 79:8, s. 1567-1570
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We present evidence for atomic site-dependent excitonic effects in the x-ray absorption spectrum of an ordered chemisorbed monolayer of C-60/Al(110). We observe that the broadening in the 5t(1u)-derived resonance and the corresponding core level resonant
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| 8. |
- Maxwell, D J, et al.
(författare)
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Synaptic connections of dorsal horn group II spinal interneurons: synapses formed with the interneurons and by their axon collaterals.
- 1997
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Ingår i: The Journal of comparative neurology. - 0021-9967. ; 380:1, s. 51-69
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Tidskriftsartikel (refereegranskat)abstract
- Five dorsal horn interneurons with monosynaptic input from group II primary afferent fibres were physiologically characterized and intracellularly labelled with horseradish peroxidase. The cells were prepared for combined light and electron microscopy, and synaptic arrangements formed by axon collaterals of interneurons and synapses formed with their dendrites and somata were examined with the electron microscope. Immunogold reactions for gamma-aminobutyric acid, glycine and glutamate were performed to determine if these synapses were excitatory or inhibitory. Axon collaterals in lamina VI formed synapses with somata and dendrites of other neurons, and collaterals of one cell also formed axoaxonic synapses. It was concluded that one cell from the sample was inhibitory, whereas the remainder were probably excitatory. Dendrites and cell bodies of interneurons were contacted by several types of synaptic bouton. The first type of bouton displayed immunoreactivity for glutamate, the second type contained both gamma-aminobutyric acid and glycine, the third type contained glycine alone, and the fourth type contained gamma-aminobutyric acid alone. Some large glutamatergic boutons were postsynaptic to other boutons. Presynaptic boutons at these axoaxonic synapses always contained gamma-aminobutyric acid but a minority also contained glycine. The results of this study demonstrate the heterogeneity of dorsal horn group II interneurons and provide evidence that they include inhibitory and probably also excitatory neurons. Boutons originating from several chemically different classes of neuron are responsible for postsynaptic inhibition of these interneurons, and the presence of axoaxonic synapses indicates that their excitatory input is also controlled presynaptically.
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| 9. |
- Maxwell, D. J., et al.
(författare)
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Synaptic relationships between serotonin-immunoreactive axons and dorsal horn spinocerebellar tract cells in the cat spinal cord
- 1996
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Ingår i: Neuroscience. - 0306-4522. ; 70, s. 247-253
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Tidskriftsartikel (refereegranskat)abstract
- Dorsal horn spinocerebellar tract cells were identified according to electrophysiological criteria in adult cats and labelled intracellularly with horseradish peroxidase. Sections containing labelled neurons were processed to reveal serotonin immunoreactivity and examined with light and electron microscopy. Numerous contacts were observed on cell bodies, and on proximal and intermediate parts of dendrites. Electron microscopic examination of contacts revealed that synaptic junctions were usually present at the region of apposition. It is concluded that serotonin has a postsynaptic action on dorsal horn spinocerebellar tract cells and that this action is mediated through conventional synapses. Copyright © 1995 IBRO. All rights reserved.
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