| 51. |
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| 52. |
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| 53. |
- Kislev, T., et al.
(författare)
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On the nature of opaque cylindrical regions formed at fibre break sites in a fragmentation test
- 2002
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Ingår i: Advanced Composites Letters. - : SAGE Publications. - 0963-6935 .- 2633-366X. ; 11:1, s. 7-13
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Tidskriftsartikel (refereegranskat)abstract
- When a single-fibre composite test is performed to obtain information about the interfacial adhesion in a composite, a gradual strain increase often causes an opaque (black) cylinder to nucleate at, and grow from, the fibre failure sites. The nature of the opaque cylinder is difficult to ascertain using optical microscopy. This is the subject of the present note. To study the inside of the opaque cylinder we use several experimental methods based on imaging the failed region: optical microscopy, laser Raman spectroscopy and scanning electron microscopy. Mechanical models, including FEM analysis and analytic equations based on the shear-lag, approach, are used to discuss the experimental work. The nature and growth mechanism of the opaque cylinder are of importance in defining the parameters and/or contributions that appear in both the force balance and the. energy balance schemes.
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| 54. |
- Wagner, G, et al.
(författare)
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Symptoms score and quality life
- 2000
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Ingår i: Erectile dysfunction. - : Health Publication Ltd. ; , s. 105-
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 55. |
- Wallen-Mackenzie, A, et al.
(författare)
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Nurr1-RXR heterodimers mediate RXR ligand-induced signaling in neuronal cells
- 2003
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Ingår i: Genes & development. - : Cold Spring Harbor Laboratory. - 0890-9369 .- 1549-5477. ; 17:24, s. 3036-3047
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Tidskriftsartikel (refereegranskat)abstract
- The retinoid X receptor (RXR) is essential as a common heterodimerization partner of several nuclear receptors (NRs). However, its function as a bona fide receptor for endogenous ligands has remained poorly understood. Such a role would depend on the existence of RXR activating ligands in vivo and on the ability of such ligands to influence relevant biological functions. Here we demonstrate the presence of endogenous RXR ligands in the embryonic central nervous system (CNS) and show that they can activate heterodimers formed between RXR and the orphan NR Nurr1 in vivo. Moreover, RXR ligands increase the number of surviving dopaminergic cells and other neurons in a process mediated by Nurr1-RXR heterodimers. These results provide evidence for a role of Nurr1 as a ligand-independent partner of RXR in its function as a bona fide ligand-activated NR. Finally, our findings identify RXR-Nurr1 heterodimers as a potential target in the treatment of neurodegenerative disease.
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| 56. |
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| 57. |
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| 58. |
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| 59. |
- Karltun, E., et al.
(författare)
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Surface reactivity of poorly-ordered minerals in podzol B horizons
- 2000
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Ingår i: Geoderma. - 0016-7061 .- 1872-6259. ; 94:04-feb, s. 265-288
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Tidskriftsartikel (refereegranskat)abstract
- The surface reactivity of mineral soil horizons from three podzolised forest soils in Scandinavia was examined. The amount of accumulated C was low, between 1.8 and 2.3% in the top of the B horizons. Selective extractions in combination with infrared (IR) spectroscopy and transmission electron microscopy (TEM) indicated a predominance of poorly-ordered imogolite-type materials (ITM) in the oxalate extractable fraction in an examined B horizons. The presence of well-ordered imogolite was only indicated in the Nyanget B3 horizon. A large proportion of free Fe was removed by ammonium oxalate. Comparisons of Mossbauer spectra (both at room temperature and at 4.2 K) before and after treatment with ammonium oxalate showed that the oxalate treatment resulted in a removal of a (super)paramagnetic Fe3+ phase? probably ferrihydrite. A comparison of the Mossbauer Fe3+ parameters at room temperature and 4.2 K indicated a close intergrowth of a ferrihydrite-like oxide with a magnetically neutral matrix, e.g., allophane. The specific surface area (SSA) was determined by N-2 adsorption before and after treatment of the samples with acid ammonium oxalate. The loss of SSA after oxalate treatment was considerable in the B horizon where only between 3.8 to 13.38 of the original SSA remained after treatment. The point of zero charge salt effect (PZSE) increased with depth in the B horizon from between 4.4 and 5.1 in the upper horizons to between 5.7 and 7.7 in the lower part of the B horizon. The increased PZSE with depth paralleled a decrease in the ratio of pyrophosphate soluble C to oxalate soluble Fe + Al. The affinity for SO42-. a goad indicator of the presence of active surface hydroxyls, was measured by comparing the H+ buffering capacity of a sample titrated in 2.5 mM Na2SO4 with a sample titrated in 5 mh I NaNO3,. The buffering capacity of the soil in the Na2SO4, electrolyte was well correlated with the amount of oxalate minus pyrophosphate soluble Fe + Al (r(2) = 0.88). The sulphate exchange capacity was considerably higher than CEC, especially in lower parts of the B horizon. The calculated surface area of the oxalate soluble material (OSM) ranged between 74 and 289 m(2) g(-1) and the calculated surface site density of the same material ranged between 0.6 to 3.3 site nm(-2). It was concluded that the surface reactivity in the B horizons is dominated by the poorly-ordered variable-charge oxides resulting in a low capacity to retain cations but a high capacity for adsorption of weak acid anions like SO42- and organic acids.
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| 60. |
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| 61. |
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| 62. |
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| 63. |
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| 64. |
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| 65. |
- Pahlm, Olle, et al.
(författare)
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Comparison of waveforms in conventional 12-lead ECGs and those derived from EASI leads in children
- 2003
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 36:1, s. 25-31
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Tidskriftsartikel (refereegranskat)abstract
- To investigate the possibility of simplifying electrocardiogram (ECG) recording in children, we compared waveforms in conventional 12-lead ECGs to those derived from EASI leads in 221 children of various ages. The conventional 12-lead ECGs and the ECGs using EASI electrode positions were collected simultaneously. We developed and determined the value of age-specific transformation coefficients for use in deriving 12-lead ECGs from the signals recorded at the EASI sites. We compared the results of using age-specific coefficients to the results of using adult coefficients and studied the "goodness-of-fit" between the conventional and the derived 12-lead ECGs. The age-specific coefficients performed slightly better than the adult coefficients, and good agreement was usually attained between the conventional 12-lead ECG and the EASI-derived 12-lead ECG. Our conclusion is that EASI leads in children have the same high levels of "goodness-of-fit" to replicate conventional 12-lead ECG waveforms, as reported earlier in adults.
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| 66. |
- Ricci, R., et al.
(författare)
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Requirement of JNK2 for scavenger receptor A-mediated foam cell formation in atherogenesis
- 2004
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Ingår i: Science. - 1095-9203. ; 306:5701, s. 1558-61
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Tidskriftsartikel (refereegranskat)abstract
- In vitro studies suggest a role for c-Jun N-terminal kinases (JNKs) in proatherogenic cellular processes. We show that atherosclerosis-prone ApoE-/- mice simultaneously lacking JNK2 (ApoE-/- JNK2-/- mice), but not ApoE-/- JNK1-/- mice, developed less atherosclerosis than do ApoE-/- mice. Pharmacological inhibition of JNK activity efficiently reduced plaque formation. Macrophages lacking JNK2 displayed suppressed foam cell formation caused by defective uptake and degradation of modified lipoproteins and showed increased amounts of the modified lipoprotein-binding and -internalizing scavenger receptor A (SR-A), whose phosphorylation was markedly decreased. Macrophage-restricted deletion of JNK2 was sufficient to decrease atherogenesis. Thus, JNK2-dependent phosphorylation of SR-A promotes uptake of lipids in macrophages, thereby regulating foam cell formation, a critical step in atherogenesis.
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| 67. |
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| 68. |
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| 69. |
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