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Search: L773:1477 2000 OR L773:1478 0933

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1.
  • Rem, Peter C., et al. (author)
  • The investigation of separability of particles smaller than 5 mm by eddy-current separation technology - Part II: novel design concepts
  • 2000
  • In: Magnetic and Electrical Separation. - : Hindawi Limited. - 1055-6915 .- 1029-0303 .- 1477-2876. ; 10:2, s. 85-105
  • Journal article (peer-reviewed)abstract
    • Separability and separation mechanisms of small particles in modern rotating type eddy-current separators (ECSs) were discussed in Part I. In order to address problems associated with this design concept, a number of novel ECSs, each with a unique design, have been developed. Part II reports on investigation into the separability and separation principles for various materials smaller than 5 mm, including fine copper wires, in three new devices: the redesigned Delft vertical ECS (VECS), prototype TNO ECS and a laboratory wet ECS (WECS). It is found that TNO ECS and WECS are more practical tools for separation of small metal particles. In particular, WECS is able to recover approximately 80% of very fine copper wires, with 0.5 mm diameter and 2 mm length. Separation principles for WECS are discussed in greater detail than other design concepts in the present study. It appears that the fledgling WECS will be most promising in the future for processing small particles. Further, aluminum separation from the -10 mm fraction of electronic scrap has been carried out using TNO ECS. It transpires that both the recovery and the grade of the aluminum concentrate are superior to those obtained with the rotary belted-drum ECS of any type.
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2.
  • Wang, Yanmin, et al. (author)
  • Purification of fine powders by a superconducting HGMS with vibration assistance
  • 2000
  • In: Magnetic and Electrical Separation. - : Hindawi Limited. - 1055-6915 .- 1029-0303 .- 1477-2876. ; 10:3, s. 161-178
  • Journal article (peer-reviewed)abstract
    • In this study, a superconducting high gradient magnetic separator (HGMS) with a matrix vibration system in dry mode was utilized to purify fine calcite and quartz powders smaller than 38 μm. The effects of the operating parameters (particle size, magnetic field/average air velocity (B0/V0), the amplitude of vibration as well as the aperture size of the expanded metal matrix) have been presented. The mechanically-based matrix vibration with the air blowing was recognized to be effective for dry purification of fine powdered materials at high magnetic fields. The function of the matrix vibration has been discussed. In addition, the results have been empirically correlated with the operating parameters used for the purification in the separator.
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3.
  • Carlsson, Lars (author)
  • Towards a sustainable Russian forest sector
  • 2000
  • In: Natural resources forum (Print). - : Wiley. - 0165-0203 .- 1477-8947. ; 24:1, s. 31-37
  • Journal article (peer-reviewed)abstract
    • Russia's forest resources are enormous, but despite almost ten years of transition, problems are still immense, in terms of commercial output and with respect to forest management. This article suggests that one way of changing the situation is to introduce community management of forests. Using the Swedish forest commons as an example, this article argues that such a change in property rights will provide an alternative to massive privatization of the forests and to the undesirable continuation or strengthening of state forest management. Finally, it is concluded that such an introduction of new property rights regimes will not provide the solution to the problems, but rather will contribute to the establishment of a better institutional framework in the Russian forest sector
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4.
  • Wågberg, Thomas, et al. (author)
  • 2D polymerization and doping of fullerenes under pressure
  • 2000
  • In: High Pressure Research vol. 18. - : Gordon & Breach. ; 18:1-6, s. 139-143
  • Conference paper (peer-reviewed)abstract
    • Tetragonal polymeric C60 has been studied by Raman spectroscopy and other methods. Attempts have been made to transform samples from the tetragonal to the orthorhom-bic phase and vice versa. The results suggest that the transformation is direct with no intermediate stage with free molecules. Tetragonal C60 has also been intercalated by potassium metal.
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5.
  • Palmgren, J (author)
  • Exponential family models and statistical genetics
  • 2000
  • In: Statistical methods in medical research. - : SAGE Publications. - 0962-2802 .- 1477-0334. ; 9:1, s. 57-72
  • Journal article (peer-reviewed)abstract
    • This article describes the evolution of applied exponential family models, starting at 1972, the year of publication of the seminal papers on generalized linear models and on Cox regression, and leading to multivariate (i) marginal models and inference based on estimating equations and (ii) random effects models and Bayesian simulation-based posterior inference. By referring to recent work in genetic epidemiology, on semiparametric methods for linkage analysis and on transmission/disequilibrium tests for haplotype transmission this paper illustrates the potential for the recent advances in applied probability and statistics to contribute to new and unified tools for statistical genetics. Finally, it is emphasized that there is a need for well-defined postgraduate education paths in medical statistics in the year 2000 and thereafter.
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6.
  • Papi, F, et al. (author)
  • Open-sea migration of magnetically disturbed sea turtles
  • 2000
  • In: Journal of Experimental Biology. - 1477-9145. ; 203:22, s. 3435-3443
  • Journal article (peer-reviewed)abstract
    • Green turtles (Chelonia mydas) that shuttle between their Brazilian feeding grounds and nesting beaches at Ascension Island in the middle of the Atlantic Ocean are a paradigmatic case of long-distance oceanic migrants. It has been suggested that they calculate their position and the direction of their target areas by using the inclination and intensity of the earths magnetic field. To test this hypothesis, we tracked, by satellite, green turtles during their postnesting migration from Ascension Island to the Brazilian coast more than 2000 km away. Seven turtles were each fitted with six powerful static magnets attached in such a way as to produce variable artificial fields around the turtle that made reliance on a geomagnetic map impossible. The reconstructed courses were very similar to those of eight turtles without magnets that were tracked over the same period and in the previous year, and no differences between magnetically disrupted and untreated turtles were found as regards navigational performance and course straightness. These findings show that magnetic cues are not essential to turtles making the return trip to the Brazilian coast. The navigational mechanisms used by these turtles remain enigmatic.
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7.
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8.
  • Andrén, Elinor, et al. (author)
  • Holocene history of the Baltic Sea as a background for assessing records of human impact in the sediments of the Gotland Basin
  • 2000
  • In: The Holocene. - : SAGE Publications. - 0959-6836 .- 1477-0911. ; 10, s. 687-702
  • Journal article (peer-reviewed)abstract
    • Sediment cores from the Gotland Basin were studied for their siliceous microfossil assemblages and organic carbon content to compare recent environmental changes in the Baltic Sea with its natural long-term history. Age models were constructed using Pb-210, Cs-137 and corrected and calibrated C-14 dates. The transgression that marks the onset of the Ancylus Lake stage is recorded in the sediments as a small increase in organic carbon coinciding with a peak in diatom abundance and increased diatom diversity. A minor occurrence of brackish-freshwater diatoms is recorded in the Ancylus Lake c. 9950-9750 cal. yr BP (c. 8900-8800 C-14 yr BP), correlating with the onset of the Initial Litorina Sea in the Bornholm Basin. A high-productivity event is recorded in the end of the Post-Litorina Sea and corresponds to the Mediaeval warm event. An alteration in the diatom assemblage contemporaneous with a decrease in organic carbon, interpreted as representing a deterioration in the climate, correlates with the start of the ‘Little Ice Age’ about 850-700 cal. yr BP. A change dated to ad 1950-1960 is probably an effect of increased nutrient availability in the open Baltic Sea. This effect of eutrophication was probably caused by increased discharge of nutrients deriving from fertilizers, as the responding diatom species partly indicate a cold climate rather than a warm one, as would have been expected if this had been only a response to the warmer climate documented during the last 100 years or so.
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9.
  • Arvanitidis, J., et al. (author)
  • High pressure study of the 2D polymeric phase of C60by means of raman spectroscopy
  • 2000
  • In: High Pressure Research. - : Taylor & Francis. - 0895-7959 .- 1477-2299. ; 18:1-6, s. 145-151
  • Journal article (peer-reviewed)abstract
    • The effect of high hydrostatic pressure, up to 12 GPa, on the intramolecular phonon frequencies and the material stability of the two-dimensional tetragonal C-60 polymer has been studied by means of Raman spectroscopy in the spectral range of the radial intramolecular modes (200-800 cm(-1)). A number of new Raman modes appear in the spectrum for pressures similar to 1.4 and similar to 5.0 GPa. The pressure coefficients for the majority of the phonon modes exhibit changes to lower values at P=4.0 GPa, which may be related to a structural modification of the 2D polymer to a more isotropic phase. The peculiarities observed in the Raman spectra are reversible and the material is stable in the pressure region investigated.
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10.
  • Baudet, C, et al. (author)
  • Positive and negative interactions of GDNF, NTN and ART in developing sensory neuron subpopulations, and their collaboration with neurotrophins
  • 2000
  • In: Development (Cambridge, England). - : The Company of Biologists. - 0950-1991 .- 1477-9129. ; 127:20, s. 4335-4344
  • Journal article (peer-reviewed)abstract
    • Glial cell line-derived neurotrophic factor (GDNF), neurturin (NTN) and neublastin/artemin (ART) are distant members of the transforming growth factor β; family, and have been shown to elicit neurotrophic effects upon several classes of peripheral and central neurons. Limited information from in vitro and expression studies has also substantiated a role for GDNF family ligands in mammalian somatosensory neuron development. Here, we show that although dorsal root ganglion (DRG) sensory neurons express GDNF family receptors embryonically, they do not survive in response to their ligands. The regulation of survival emerges postnatally for all GDNF family ligands. GDNF and NTN support distinct subpopulations that can be separated with respect to their expression of GDNF family receptors, whereas ART supports neurons in populations that are also responsive to GDNF or NTN. Sensory neurons that coexpress GDNF family receptors are medium sized, whereas small-caliber nociceptive cells preferentially express a single receptor. In contrast to brain-derived neurotrophic factor (BDNF)-dependent neurons, embryonic nerve growth factor (NGF)-dependent nociceptive neurons switch dependency to GDNF, NTN and ART postnatally. Neurons that survive in the presence of neurotrophin 3 (NT3) or neurotrophin 4 (NT4), including proprioceptive afferents, Merkel end organs and D-hair afferents, are also supported by GDNF family ligands neonatally, although at postnatal stages they lose their dependency on GDNF and NTN. At late postnatal stages, ART prevents survival elicited by GDNF and NTN. These data provide new insights on the roles of GDNF family ligands in sensory neuron development.
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11.
  • Bengtsson, Anders, et al. (author)
  • Activation of type I interferon system in systemic lupus erythematosus correlates with disease activity but not with antiretroviral antibodies
  • 2000
  • In: Lupus. - : SAGE Publications. - 0961-2033 .- 1477-0962. ; 9:9, s. 664-671
  • Journal article (peer-reviewed)abstract
    • The objective was to investigate the relation between serum levels of interferon-alpha (IFN-alpha), the activity of an endogenous IFN-alpha inducing factor (SLE-IIF), clinical and immunological disease activity as well as serum levels of antiretroviral antibodies in SLE. Serum levels of IFN-alpha were measured in serial sera from 30 patients sampled at different stages of disease activity (SLEDAI score). The SLE-IIF activity was measured by its ability to induce IFN-alpha production in cultures of normal peripheral blood mononuclear cells. Both serum IFN-alpha and SLE-IIF increased markedly at flare in serially followed patients. The SLEDAI score, levels of anti-dsDNA antibodies and IL-10 correlated positively, and complement components Clq, C3 and leukocytes correlated inversely with serum concentrations of IFN-alpha. The extent of multiple organ involvement correlated with serum IFN-alpha. No relation between concentrations of retroviral peptide binding antibodies and IFN-alpha or SLE-IIF activity was found. The close relationship between disease activity in SLE patients and IFN-alpha serum levels suggests that activation of the type 1 IFN system might be of importance in the disease process.
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12.
  • Bengtsson, Tommy, et al. (author)
  • Childhood misery and disease in later life : The effects on mortality in old age of hazards experienced in early life, southern Sweden, 1760-1894
  • 2000
  • In: Population Studies. - : Informa UK Limited. - 0032-4728 .- 1477-4747. ; 54:3, s. 263-277
  • Journal article (peer-reviewed)abstract
    • This paper assesses the importance of early-life conditions relative to the prevailing conditions for mortality by cause of death in later life using historical data for four rural parishes in southern Sweden for which both demographic and economic data are very good. Longitudinal demographic data for individuals are combined with household socio-economic data and community data on food costs and the disease load using a Cox regression framework. We find strong support for the hypothesis that the disease load experienced during the first year of life has a strong impact on mortality in later life, in particular on the outcome of airborne infectious diseases. Hypotheses about the effects of the disease load on mothers during pregnancy and access to nutrition during first years of life are not supported. Contemporary short-term economic stress on the elderly was generally of limited importance although mortality varied by socio-economic group.
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13.
  • Berggren, Ingela, et al. (author)
  • The influence of clinical supervision on nurses' moral decision making.
  • 2000
  • In: Nursing Ethics. - London : Edward Arnold. - 0969-7330 .- 1477-0989. ; 7:2, s. 124--133
  • Journal article (peer-reviewed)abstract
    • The aim of this study was to investigate the influence of clinical supervision on nurses´ moral decision making. The sample consisted of 15 registered nurses who took part in clinical supervision sessions. Data were obtained from interviews and analysed by a hermeneutic transformative process. The hermeneutic interpretation revealed four themes: increased self-assurance, an increased ability to support the patient, an increased ability to be in a relationship with the patient, and an increased ability to take responsibility. In conclusion, it seems that clinical supervision enhances nurses´ ability to provide care on the basis of their decision making. However, the qualitative and structural aspects of clinical supervision have to be investigated further in order to develop professional insight into the way that nurses think and react. 
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14.
  • Chomez, P, et al. (author)
  • Increased cell death and delayed development in the cerebellum of mice lacking the rev-erbA(alpha) orphan receptor
  • 2000
  • In: Development (Cambridge, England). - : The Company of Biologists. - 0950-1991 .- 1477-9129. ; 127:7, s. 1489-1498
  • Journal article (peer-reviewed)abstract
    • The rev-erbAα gene, belonging to the steroid receptor superfamily of transcription factors, is highly conserved during evolution but little is known so far about its functions in development or in adult physiology. Here, we describe genetically altered mice lacking the rev-erbAα gene. These animals do not show any obvious phenotype in either fat tissue or skeletal muscle, despite the known regulation of rev-erbAα expression during adipocyte and myotube differentiation in vitro. However, during the second week of life, the cerebellum of rev-erbAα mutants presents several unexpected abnormalities, such as alterations in the development of Purkinje cells, delay in the proliferation and migration of granule cells from the external granule cell layer and increased apoptosis of neurons in the internal granule cell layer. Interestingly, the expression pattern of rev-erbAα suggests that the abnormalities observed in the external granule cell layer could be secondary to Purkinje cell alterations. Taken together, our data underline the importance of rev-erbAα expression for the appropriate balance of transcriptional activators and repressors during postnatal cerebellar development.
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15.
  • Dircksen, Heinrich, 1954-, et al. (author)
  • Two orcokinins and the novel octapeptide orcomyotropin in the hindgut of the crayfish Orconectes limosus : identified myostimulatory neuropeptides originating together in neurones of the terminal abdominal ganglion
  • 2000
  • In: Journal of Experimental Biology. - 0022-0949 .- 1477-9145. ; 203:18, s. 2807-2818
  • Journal article (peer-reviewed)abstract
    • The tridecapeptides Asn(13)-orcokinin and Val(13)-orcokinin, two known members of the orcokinin neuropeptide family native to crustaceans, and a novel octapeptide, orcomyotropin, FDAFTTGFamide, have been identified from extracts of hindguts of the crayfish Orconectes limosus using an isolated hindgut contractility bioassay, high-performance liquid chromatography, microsequencing and mass spectrometry. All three peptides display strong inotropic actions on crayfish hindguts. Orcomyotropin showed higher potency than the two orcokinins. Threshold concentration was approximately 5 x 10(-12)mol l(-1)versus 10(-10)mol l(-1) for the two orcokinins. An approximately fivefold increase in contraction amplitude was observed with 10(-9)mol l(-1) orcomyotropin and 10(-7)mol l(-1) of the orcokinins. Asn(13)- and Val(13)-orcokinin did not differ significantly with regard to their biological effects. Semi-isolated crayfish hearts and locust oviducts did not respond to the three peptides. Immunocytochemistry using antisera against Asn(13)-orcokinin and orcomyotropin showed that these neuropeptides are co-localized in approximately 80-90 neurones of the terminal abdominal ganglion that have been shown to innervate the entire hindgut muscularis via the intestinal nerve. The neurones form elaborate terminal branches preferentially on longitudinal hindgut muscles. Orcomyotropin is a novel crustacean member of the GF-amide family of myotropic and/or allatotropic neuropeptides from annelids, molluscs and insects.
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16.
  • Domínguez Reyes, Edmé, 1952, et al. (author)
  • Kvinnor, forskning, familj
  • 2000
  • In: Feministiskt perspektiv (dept. for Women's Studies, Göteborg University). - 1403-1477. ; 2000:2
  • Journal article (other academic/artistic)
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17.
  • Donovan, MJ, et al. (author)
  • Brain derived neurotrophic factor is an endothelial cell survival factor required for intramyocardial vessel stabilization
  • 2000
  • In: Development (Cambridge, England). - : The Company of Biologists. - 0950-1991 .- 1477-9129. ; 127:21, s. 4531-4540
  • Journal article (peer-reviewed)abstract
    • Brain derived neurotrophic factor, BDNF, is a neurotrophin best characterized for its survival and differentiative effects on neurons expressing the trk B receptor tyrosine kinase. Although many of these neurons are lost in the BDNF−/− mouse, the early postnatal lethality of these animals suggests a wider function for this growth factor. Here, we demonstrate that deficient expression of BDNF impairs the survival of endothelial cells in intramyocardial arteries and capillaries in the early postnatal period, although the embryonic vasculature can remodel into arteries, capillaries and veins. BDNF deficiency results in a reduction in endothelial cell-cell contacts and in endothelial cell apoptosis, leading to intraventricular wall hemorrhage, depressed cardiac contractility and early postnatal death. Vascular hemorrhage is restricted to cardiac vessels, reflecting the localized expression of BDNF and trk B by capillaries and arterioles in this vascular bed. Conversely, ectopic BDNF overexpression in midgestational mouse hearts results in an increase in capillary density. Moreover, BDNF activation of endogenous trk B receptors supports the survival of cardiac microvascular endothelial cells cultured from neonatal mice. These results establish an essential role for BDNF in maintaining vessel stability in the heart through direct angiogenic actions on endothelial cells.
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18.
  • Filonova, LH, et al. (author)
  • Two waves of programmed cell death occur during formation and development of somatic embryos in the gymnosperm, Norway spruce
  • 2000
  • In: Journal of cell science. - : The Company of Biologists. - 0021-9533 .- 1477-9137. ; 113113 Pt 24:24, s. 4399-4411
  • Journal article (peer-reviewed)abstract
    • In the animal life cycle, the earliest manifestations of programmed cell death (PCD) can already be seen during embryogenesis. The aim of this work was to determine if PCD is also involved in the elimination of certain cells during plant embryogenesis. We used a model system of Norway spruce somatic embryogenesis, which represents a multistep developmental pathway with two broad phases. The first phase is represented by proliferating proembryogenic masses (PEMs). The second phase encompasses development of somatic embryos, which arise from PEMs and proceed through the same sequence of stages as described for their zygotic counterparts. Here we demonstrate two successive waves of PCD, which are implicated in the transition from PEMs to somatic embryos and in correct embryonic pattern formation, respectively. The first wave of PCD is responsible for the degradation of PEMs when they give rise to somatic embryos. We show that PCD in PEM cells and embryo formation are closely interlinked processes, both stimulated upon withdrawal or partial depletion of auxins and cytokinins. The second wave of PCD eliminates terminally differentiated embryo-suspensor cells during early embryogeny. During the dismantling phase of PCD, PEM and embryo-suspensor cells exhibit progressive autolysis, resulting in the formation of a large central vacuole. Autolytic degradation of the cytoplasm is accompanied by lobing and budding-like segmentation of the nucleus. Nuclear DNA undergoes fragmentation into both large fragments of about 50 kb and multiples of approximately 180 bp. The tonoplast rupture is delayed until lysis of the cytoplasm and organelles, including the nucleus, is almost complete. The protoplasm then disappears, leaving a cellular corpse represented by only the cell wall. This pathway of cell dismantling suggests overlapping of apoptotic and autophagic types of PCD during somatic embryogenesis in Norway spruce.
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19.
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20.
  • Gudmundsson, G A, et al. (author)
  • Sanderlings (Calidris alba) have a magnetic compass: Orientation experiments during spring migration in Iceland
  • 2000
  • In: Journal of Experimental Biology. - 1477-9145. ; 203:20, s. 3137-3144
  • Journal article (peer-reviewed)abstract
    • The migratory orientation of sanderlings (Calidris alba) was investigated with cage experiments during the spring migration in southwest Iceland. Sanderlings were exposed to 90 degrees counterclockwise-shifted magnetic fields under both clear skies and natural overcast. Clear sky control tests resulted in a northerly mean direction, in agreement with predictions based on ringing recovery data and earlier visual observations of departing flocks. Sanderlings closely followed experimental deflections of magnetic fields when tested under clear skies. Control experiments under natural overcast resulted in a bimodal distribution approximately coinciding with the magnetic north-south axis. Overcast tests did not reveal any predictable response to the experimental treatment, but instead resulted in a non-significant circular distribution. The time of orientation experiments in relation to the tidal cycle affects the motivation of the birds to depart, as shown by the lower directional scatter of headings of individuals tested within the appropriate tidal window under clear skies. Sanderlings were significantly more likely to become inactive under overcast conditions than under clear sky conditions. The results demonstrate, for the first time, that a wader species such as the sanderling possesses a magnetic compass and suggest that magnetic cues are of primary directional importance. However, overcast experiments indicate that both celestial and geomagnetic information are needed for sanderlings to realize a seasonally appropriate migratory orientation.
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21.
  • Gunhaga, Lena, et al. (author)
  • Sonic hedgehog signaling at gastrula stages specifies ventral telencephalic cells in the chick embryo
  • 2000
  • In: Development. - 0950-1991 .- 1477-9129. ; 127:15, s. 3283-3293
  • Journal article (peer-reviewed)abstract
    • A secreted signaling factor, Sonic hedgehog (Shh), has a crucial role in the generation of ventral cell types along the entire rostrocaudal axis of the neural tube. At caudal levels of the neuraxis, Shh is secreted by the notochord and floor plate during the period that ventral cell fates are specified. At anterior prosencephalic levels that give rise to the telencephalon, however, neither the prechordal mesoderm nor the ventral neural tube expresses Shh at the time that the overt ventral character of the telencephalon becomes evident. Thus, the precise role and timing of Shh signaling relevant to the specification of ventral telencephalic identity remains unclear. By analysing neural cell differentiation in chick neural plate explants we provide evidence that neural cells acquire molecular properties characteristic of the ventral telencephalon in response to Shh signals derived from the anterior primitive streak/Hensen's node region at gastrula stages. Exposure of prospective anterior prosencephalic cells to Shh at this early stage is sufficient to initiate a temporal program of differentiation that parallels that of neurons generated normally in the medial ganglionic eminence subdivision of the ventral telencephalon.
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22.
  • Hauri, HP, et al. (author)
  • ERGIC-53 and traffic in the secretory pathway
  • 2000
  • In: Journal of cell science. - : The Company of Biologists. - 0021-9533 .- 1477-9137. ; 113113 ( Pt 4):4, s. 587-596
  • Journal article (peer-reviewed)abstract
    • The ER-Golgi intermediate compartment (ERGIC) marker ERGIC-53 is a mannose-specific membrane lectin operating as a cargo receptor for the transport of glycoproteins from the ER to the ERGIC. Lack of functional ERGIC-53 leads to a selective defect in secretion of glycoproteins in cultured cells and to hemophilia in humans. Beyond its interest as a transport receptor, ERGIC-53 is an attractive probe for studying numerous aspects of protein trafficking in the secretory pathway, including traffic routes, mechanisms of anterograde and retrograde traffic, retention of proteins in the ER, and the function of the ERGIC. Understanding these fundamental processes of cell biology will be crucial for the elucidation and treatment of many inherited and acquired diseases, such as cystic fibrosis, Alzheimer's disease and viral infections.
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23.
  • Huang, WX, et al. (author)
  • Systemic upregulation of CD40 and CD40 ligand mRNA expression in multiple sclerosis
  • 2000
  • In: Multiple sclerosis (Houndmills, Basingstoke, England). - : SAGE Publications. - 1352-4585 .- 1477-0970. ; 6:2, s. 61-65
  • Journal article (peer-reviewed)abstract
    • It is increasingly clear that the CD40 and CD40 ligand (CD40L) receptor-ligand pair mediates a crucial activation signal in both cell-mediated and humoral immune responses. Here, we detected mRNA levels of CD40 and CD40L in non-stimulated peripheral blood mononuclear cells in 46 patients with multiple sclerosis (MS) and 46 healthy controls by a competitive RT-PCR procedure allowing quantification without previous culture or antigenic stimulation. The levels of CD40 and CD40L mRNA were markedly increased in MS patients (P <0.0001) compared with healthy controls. There was no difference between clinical MS subgroups or stage of disease. Our findings indicate that, although MS is an organ specific disorder an increased signaling via the CD40 and CD40L pathway may be present at the systemic level. The nature of this upregulation, whether primary or secondary to the organ-specific autoimmune response, is yet to be determined. Since interference with CD40/CD40L is an effective way to interfere with autoimmune model diseases such as experimental autoimmune encephalomyelitis, it may be relevant to investigate further the role of these molecules in the pathogenesis of MS.
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24.
  • Ingemarsson, AH, et al. (author)
  • Balance function and fall-related efficacy in patients with newly operated hip fracture
  • 2000
  • In: Clinical rehabilitation. - : SAGE Publications. - 0269-2155 .- 1477-0873. ; 14:5, s. 497-505
  • Journal article (peer-reviewed)abstract
    • Objective: To investigate the relation between fall-related efficacy in daily-life activities and functional as well as instrumental tests of balance in patients with hip fracture. Design: Analysis of different aspects of balance using the Falls Efficacy Scale, Swedish version FES(S), questions on fear of falling, Functional Reach (FR) and tests on a balance platform (Chattanooga). Subjects: Fifty-five elderly inpatients (mean age 82.3) with newly operated hip fracture who were assessed during the last week in hospital before discharge. Results: The results showed a significant relationship between the subjective ability measured with the FES(S) and the objectively measured balance in the Functional Reach test and also between fall-related efficacy measured with FES(S) and fear of falling. Very few significant correlations were found between the results from balance tests on the force platform and those obtained with FES(S) and FR. Conclusions: Both the Falls Efficacy Scale, Swedish version, and the Functional Reach have been shown to be useful in analysing balance function in elderly patients newly operated on for hip fracture. The Falls Efficacy Scale also indicates which of the daily activities the patient perceives as troublesome and thus require further training.
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25.
  • Lindström, Åke, et al. (author)
  • Avian pectoral muscle size rapidly tracks body mass changes during flight, fasting and fuelling
  • 2000
  • In: Journal of Experimental Biology. - 1477-9145. ; 203:5, s. 913-919
  • Journal article (peer-reviewed)abstract
    • We used ultrasonic imaging to monitor short-term changes in the pectoral muscle size of captive red knots Calidris canutus. Pectoral muscle thickness changed rapidly and consistently in parallel with body mass changes caused by flight, fasting and fuelling. Four knots flew repeatedly for 10 h periods in a wind tunnel. Over this period, pectoral muscle thickness decreased in parallel with the decrease in body mass. The change in pectoral muscle thickness during flight was indistinguishable from that during periods of natural and experimental fasting and fuelling. The body-mass-related variation in pectoral muscle thickness between and within individuals was not related to the amount of flight, indicating that changes in avian muscle do not require power-training as in mammals. Our study suggests that it is possible for birds to consume and replace their flight muscles on a time scale short enough to allow these muscles to be used as part of the energy supply for migratory flight. The adaptive significance of the changes in pectoral muscle mass cannot be explained by reproductive needs since our knots were in the early winter phase of their annual cycle. Instead, pectoral muscle mass changes may reflect (i) the breakdown of protein during heavy exercise and its subsequent restoration, (ii) the regulation of flight capacity to maintain optimal flight performance when body mass varies, or (iii) the need for a particular protein:fat ratio in winter survival stores.
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26.
  • Lutzen, K, et al. (author)
  • Moral sensitivity: some differences between nurses and physicians
  • 2000
  • In: Nursing ethics. - : SAGE Publications. - 0969-7330 .- 1477-0989. ; 7:6, s. 520-530
  • Journal article (peer-reviewed)abstract
    • We report the results of an investigation of nurses’ and physicians’ sensitivity to ethical dimensions of clinical practice. The sample consisted of 113 physicians working in general medical settings, 665 psychiatrists, 150 nurses working in general medical settings, and 145 nurses working in psychiatry. The instrument used was the Moral Sensitivity Questionnaire (MSQ), a self-reporting Likert-type questionnaire consisting of 30 assumptions related to moral sensitivity in health care practice. Each of these assumptions was categorized into a theoretical dimension of moral sensitivity: relational orientation, structuring moral meaning, expressing benevolence, modifying autonomy, experiencing moral conflict, and following the rules. Significant differences in responses were found between health care professionals from general medical settings and those working in psychiatry. The former agreed to a greater extent with the assumptions in the categories ‘meaning’ and ‘autonomy’ and to a lesser degree with the categories ‘benevolence’ and ‘conflict’. Moreover, those from the psychiatric sector agreed to a greater extent to the use of coercion if necessary. Significant differences were also found for some of the MSQ categories, between physicians and nurses, and between males and females.
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27.
  • Majumdar, A, et al. (author)
  • Zebrafish no isthmus reveals a role for pax2.1 in tubule differentiation and patterning events in the pronephric primordia
  • 2000
  • In: Development (Cambridge, England). - : The Company of Biologists. - 0950-1991 .- 1477-9129. ; 127:10, s. 2089-2098
  • Journal article (peer-reviewed)abstract
    • Pax genes are important developmental regulators and function at multiple stages of vertebrate kidney organogenesis. In this report, we have used the zebrafish pax2.1 mutant no isthmus to investigate the role for pax2.1 in development of the pronephros. We demonstrate a requirement for pax2.1 in multiple aspects of pronephric development including tubule and duct epithelial differentiation and cloaca morphogenesis. Morphological analysis demonstrates that noi(−)larvae specifically lack pronephric tubules while glomerular cell differentiation is unaffected. In addition, pax2.1 expression in the lateral cells of the pronephric primordium is required to restrict the domains of Wilms' tumor suppressor (wt1) and vascular endothelial growth factor (VEGF) gene expression to medial podocyte progenitors. Ectopic podocyte-specific marker expression in pronephric duct cells correlates with loss of expression of the pronephric tubule and duct-specific markers mAb 3G8 and a Na(+)/K(+) ATPase (α)1 subunit. The results suggest that the failure in pronephric tubule differentiation in noi arises from a patterning defect during differentiation of the pronephric primordium and that mutually inhibitory regulatory interactions play an important role in defining the boundary between glomerular and tubule progenitors in the forming nephron.
  •  
28.
  •  
29.
  • Pennycuick, C J, et al. (author)
  • Horizontal flight of a swallow (Hirundo rustica) observed in a wind tunnel, with a new method for directly measuring mechanical power
  • 2000
  • In: Journal of Experimental Biology. - 1477-9145. ; 203:11, s. 1755-1765
  • Journal article (peer-reviewed)abstract
    • A swallow flying in the Lund wind tunnel was observed from the side and from behind, by two synchronised highspeed video cameras. The side-view camera provided a record of the vertical position of a white mark, applied to the feathers behind and below the eye, from which the vertical acceleration was obtained. The rear-view camera provided measurements of the mean angle of the left and right humeri above horizontal. From these data, the force acting on the body, the moment applied by each pectoralis muscle to the humerus and the rotation of the humerus were estimated and used to analyse the time course of a number of variables, including the work done by the muscles in each wing beat. The average mechanical power turned out to be more than that predicted on the basis of current estimates of body drag coefficient and profile power ratio, possibly because the bird was not flying steadily in a minimum-drag configuration, We hope to develop the method further by correlating the mechanical measurements with observations of the vortex wake and to apply it to birds that have been conditioned to hold a constant position in the test section.
  •  
30.
  • Perissinotto, D, et al. (author)
  • Avian neural crest cell migration is diversely regulated by the two major hyaluronan-binding proteoglycans PG-M/versican and aggrecan
  • 2000
  • In: Development: For advances in developmental biology and stem cells. - 1477-9129. ; 127:13, s. 2823-2842
  • Journal article (peer-reviewed)abstract
    • It has been proposed that hyaluronan-binding proteoglycans play an important role as guiding cues during neural crest (NC) cell migration, but their precise function has not been elucidated. In this study, we examine the distribution, structure and putative role of the two major hyaluronan-binding proteoglycans, PG-M/versicans and aggrecan, during the course of avian NC development. PG-M/versicans V0 and V1 are shown to be the prevalent isoforms at initial and advanced phases of NC cell movement, whereas the V2 and V3 transcripts are first detected following gangliogenesis. During NC cell dispersion, mRNAs for PG-M/versicans V0/V1 are transcribed by tissues lining the NC migratory pathways, as well as by tissues delimiting nonpermissive areas. Immunohistochemistry confirm the deposition of the macromolecules in these regions and highlight regional differences in the density of these proteoglycans. PG-M/versicans assembled within the sclerotome rearrange from an initially uniform distribution to a preferentially caudal localization, both at the mRNA and protein level. This reorganization is a direct consequence of the metameric NC cell migration through the rostral portion of the somites. As suggested by previous in situ hybridizations, aggrecan shows a virtually opposite distribution to PG-M/versicans being confined to the perinotochordal ECM and extending dorsolaterally in a segmentally organized manner eventually to the entire spinal cord at axial levels interspacing the ganglia. PG-M/versicans purified from the NC migratory routes are highly polydispersed, have an apparent M(r) of 1,200-2,000 kDa, are primarily substituted with chondroitin-6-sulfates and, upon chondroitinase ABC digestion, are found to be composed of core proteins with apparent M(r )of 360-530, 000. TEM/rotary shadowing analysis of the isolated PG-M/versicans confirmed that they exhibit the characteristic bi-globular shape, have core proteins with sizes predicted for the V0/V1 isoforms and carry relatively few extended glycosaminoglycan chains. Orthotopical implantation of PG-M/versicans immobilized onto transplantable micromembranes tend to 'attract' moving cells toward them, whereas similar implantations of a notochordal type-aggrecan retain both single and cohorts of moving NC cells in close proximity of the implant and thereby perturb their spatiotemporal migratory pattern. NC cells fail to migrate through three-dimensional collagen type I-aggrecan substrata in vitro, but locomote in a haptotactic manner through collagen type I-PG-M/versican V0 substrata via engagement of HNK-1 antigen-bearing cell surface components. The present data suggest that PG-M/versicans and notochordal aggrecan exert divergent guiding functions during NC cell dispersion, which are mediated by both their core proteins and glycosaminoglycan side chains and may involve 'haptotactic-like' motility phenomena. Whereas aggrecan defines strictly impenetrable embryonic areas, PG-M/versicans are central components of the NC migratory pathways favoring the directed movement of the cells.
  •  
31.
  • Phlippen, M K, et al. (author)
  • Ecdysis of decapod crustaceans is associated with a dramatic release of crustacean cardioactive peptide into the haemolymph.
  • 2000
  • In: Journal of Experimental Biology. - 0022-0949 .- 1477-9145. ; 203:Pt 3, s. 521-36
  • Journal article (peer-reviewed)abstract
    • On the basis of detailed analyses of morphological characteristics and behavioural events associated with ecdysis in a crab (Carcinus maenas) and a crayfish (Orconectes limosus), a comprehensive substaging system has been introduced for the ecdysis stage of the moult cycle of these decapod crustaceans. In a remarkably similar stereotyped ecdysis sequence in both species, a passive phase of water uptake starting with bulging and rupture of thoracoabdominal exoskeletal junctions is followed by an active phase showing distinct behavioural changes involved in the shedding of the head appendages, abdomen and pereiopods. Together with an enzyme immunoassay for crustacean cardioactive peptide (CCAP), the substaging has been used to demonstrate a large, rapid and reproducible peak in haemolymph CCAP levels (increases of approximately 30-fold in the crab and more than 100-fold in the crayfish compared with intermoult titres) during the later stages of active ecdysis. We suggest that the release of CCAP (accumulated in late premoult) from the crab pericardial organs or the crayfish ventral nerve cord accounts for many of the changes in behaviour and physiology seen during ecdysis and that this neurohormone is likely to be of critical importance in crustaceans and other arthropods.
  •  
32.
  • Randers, Ingrid, et al. (author)
  • The experiences of elderly people in geriatric care with special reference to integrity
  • 2000
  • In: Nursing Ethics. - : SAGE Publications. - 0969-7330 .- 1477-0989. ; 7:6, s. 503-19
  • Journal article (peer-reviewed)abstract
    • The aim of this study was to obtain an increased understanding of the experiences of elderly people in geriatric care, with special reference to integrity. Data were collected through qualitative interviews with elderly people and, in order to obtain a description of caregivers' integrity-promoting or non-promoting behaviours, participant observations and qualitative interviews with nursing students were undertaken. Earlier studies on the integrity of elderly people mainly concentrated on their personal and territorial space, so Kihlgren and Thorsén opened up the possibility of considering the concept of integrity from a broader view by recognizing its relationship to the larger framework of the self-concept. Based on this, findings in the present study indicate that elderly people's integrity relating to their corporal self were the least violated. On the other hand, their psychological, information and cultural selves were the most exposed. The study also identified a further dimension (i.e. one relating to social self), which should be included in the concept of integrity because respecting elderly people's social self reduces their feelings of loneliness, isolation and seclusion. In summary, the results indicate that the concept of integrity is complex and has several dimensions.
  •  
33.
  • Rosén, P, et al. (author)
  • Near-infrared spectrometry (NIRS) : a new tool for inferring past climatic changes from lake sediments
  • 2000
  • In: The Holocene. - : SAGE Publications. - 0959-6836 .- 1477-0911. ; 10:2, s. 161-166
  • Journal article (peer-reviewed)abstract
    • This study tests the hypothesis that lake sediments contain climate-related information that can be detected by near-infrared spectrometry (NIRS), and that NIRS can be used to infer past climatic changes from analysis of sediment cores. NIRS is a rapid and non-destructive technique that measures attributes of the chemical composition of organic materials. A training set of 76 lakes from northern Sweden, spanning a broad altitudinal gradient, was used to assess whether lake altitude and vegetation zones can be modelled from NIR spectra of surface sediments (0-1 cm) using partial least squares (PLS) regression and soft independent modelling of class analogies (SIMCA) classification. Lake altitude served as a surrogate variable reflecting differences in climatic conditions among sites. After spectral filtering using orthogonal signal correction (OSC), cross-validated predictions explained 86% of the variance in altitude and the prediction error (root mean square error) was 78 m, corresponding to 8.3% of the gradient (390-1250 m above sea level). To evaluate the significance of NIR spectral differences between surface sediments of lakes in different vegetation zones (mountain-birch forest, dwarf shrub and alpine heath), principal component analysis (PCA) models were developed separately for lakes in each vegetation zone. Multivariate classification analysis demonstrated that NIR spectra of surficial sediments differed between lakes located in different vegetation zones. A separate sediment data set from 56 lakes was used to assess sediment ageing effects on NIR signals. Marked similarities between NLR spectra in surface sediments (0-1 cm) and sediments from 1-2 cm depth indicated that degradation of organic material following sediment consolidation resulted in little loss or change of climate-related information. Finally, to assess the ability of NIRS methods to reconstruct past climatic changes over Holocene timescales, we applied the NIRS-altitude model to sediments in a core from a small mountain lake. Estimates of mean July air temperature based on the NIRS-altitude transfer function showed similar trends compared with inferences from chironomids, diatoms and pollen from the same core. Overall, the results indicate that changes in NIR spectra from lake sediments reflect differences in climate, and that NIRS models based on surface-sediment samples can be applied to sediment cores for retrospective analysis.
  •  
34.
  • Sahlberg-Blom, Eva, et al. (author)
  • Patient participation in decision making at the end of life as seen by a close relative
  • 2000
  • In: Nursing Ethics. - : SAGE Publications. - 0969-7330 .- 1477-0989. ; 7:4, s. 296-313
  • Journal article (peer-reviewed)abstract
    • The aim of the present study was to describe variations in patientparticipation in decisions about care planningduring the final phase of life for a group of gravely ill patients, and how the different actors’manner of acting promotes or impedes patientparticipation. Thirty-seven qualitative research interviewswere conducted with relatives of the patients.The patients’ participation in the decisionscould be categorized into four variations: self-determination,co-determination, delegation and nonparticipation.The manner in which patients, relatives andcaregivers acted differed in the respective variations; thisseemed either to promote or to impede the patients’opportunities of participating in the decisionmaking. The possibility for participation seems to be context dependent and affected by many factors suchas the dying patient’s personality, thesocial network, the availability of different forms of care,cultural values, and the extent to which nursesand other caregivers of the different formsof care can and want to support the wishes of the patients andrelatives in the decision-making process.
  •  
35.
  • Sonde, L, et al. (author)
  • Low TENS treatment on post-stroke paretic arm: a three-year follow-up
  • 2000
  • In: Clinical rehabilitation. - : SAGE Publications. - 0269-2155 .- 1477-0873. ; 14:1, s. 14-19
  • Journal article (peer-reviewed)abstract
    • Objective: To determine whether stroke patients with initial increases in arm motor recovery following low-frequency transcutaneous electrical nerve stimulation (low TENS) treatment go on to show long-term benefits. Also whether the same therapy results in long-term improvements in motor function, spasticity or activities of daily living (ADL). Design: A three-year follow-up study. Subjects: Twenty-eight stroke patients, who had participated in a randomized trial of daily treatment with low-frequency (1.7 Hz) transcutaneous electrical nerve stimulation (low TENS) on the paretic arm for three months starting 6–12 months after stroke. Outcomes: Fugl-Meyer Motor Performance Scale for evaluation of changes in arm motor function. A 6-point Ashworth Scale to measure spasticity. Barthel Index to evaluate performance in ADL. Results: Motor function of the paretic arm had deteriorated in both treatment and control groups. Increased spasticity was seen in both groups. ADL score remained at a similar level in the low TENS group, whereas the control group had deteriorated during the same time period. Conclusions: Low TENS stimulation started 6–12 months after stroke may not have a specific effect on arm motor function years after completion of treatment.
  •  
36.
  • Svedberg, B, et al. (author)
  • The morality of treating patients with depot neuroleptics: the experience of community psychiatric nurses
  • 2000
  • In: Nursing ethics. - : SAGE Publications. - 0969-7330 .- 1477-0989. ; 7:1, s. 35-46
  • Journal article (peer-reviewed)abstract
    • The aim of this qualitative study was to gain an understanding of the meaning that community psychiatric nurses impart to their everyday interactions with patients in depot neuroleptic treatment situations. Nine experienced community psychiatric nurses were interviewed using semistructured, open-ended questions. Data analysis was by the phenomenological descriptive method according to Giorgi. Four themes were identified, highlighting aspects of the moral meaning of treating patients with depot neuroleptics: (1) ‘benevolent justification’ occurs when nurses perceive that the patient’s welfare is at stake; (2) ‘inability to advocate the patients’ best interest’ occurs when nurses feel they are at a disadvantage; (3) ‘accommodative interactions’ occur when nurses are able to respond to a patient’s expressed needs; and (4) ‘acceptable advocacy’ occurs when physicians are sensitive to nurses’ suggestions on patients’ treatment. The findings indicate that treatment care planning involving both patients and nurses is essential to enhance patients’ autonomy, which is a precondition for satisfactory interactions. This phenomenological study describes the meaning that nurses give to administering depot neuroleptic injections to patients in the context of community psychiatric clinics. The phenomenon of concern was identified as the moral aspect in the interactions with individual patients in the treatment situation.
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37.
  • Söderlund, Anne, et al. (author)
  • Acute whiplash-associated disorders (WAD) : the effects of early mobilization and prognostic factors in long-term symptomatology.
  • 2000
  • In: Clinical Rehabilitation. - : SAGE Publications. - 0269-2155 .- 1477-0873. ; 14:5, s. 457-467
  • Journal article (peer-reviewed)abstract
    • OBJECTIVE: To compare two different home exercise programmes for patients with acute whiplash-associated disorders (WAD). A further aim was to describe the initial prognostic variables related to self-reported pain at six months follow-up. DESIGN: A randomized treatment study with a follow-up period of six months. SETTINGS: The study was undertaken in an orthopaedic clinic at a university hospital. SUBJECTS: A total of 59 symptomatic (neck pain, stiffness, etc.) patients with acute whiplash injury. INTERVENTIONS: Patients were randomized to a regular treatment group (RT group) and an additional-exercise treatment group (AT group). MAIN OUTCOME MEASURES: Pain Disability Index (PDI), Self-Efficacy Scale (SES), Coping Strategies Questionnaire (CSQ), neck range of motion (ROM), head posture, kinaesthetic sensibility, visual analogue scale (VAS). RESULTS: Patients given an additional exercise did not improve more than patients with regular treatment. Only one CSQ item, 'Ability to decrease pain', showed a significant difference between the groups in its pattern of change over time: the AT group had a significant increase between three and six months whilst values in the RT group decreased. Nonsymptomatic patients at six months follow-up were characterized by initially better self-efficacy, lower disability and significantly different patterns in the use of 'behavioural coping strategies' when compared with symptomatic patients. The nonsymptomatic patients also reported more frequent training than symptomatic patients, i.e. they complied better with the treatment regime. CONCLUSION: This home exercise programme, including training of neck and shoulder ROM, relaxation and general advice seems to be sufficient treatment for acute WAD patients when used on a daily basis. Additionally, patients reporting low self-efficacy and high disability levels may profit from more attention initially, as these psychological factors are significant predictors of pain at long-term follow-up.
  •  
38.
  • Valverius, E, et al. (author)
  • Palliative care, assisted suicide and euthanasia: nationwide questionnaire to Swedish physicians
  • 2000
  • In: Palliative medicine. - : SAGE Publications. - 0269-2163 .- 1477-030X. ; 14:2, s. 141-148
  • Journal article (peer-reviewed)abstract
    • The objective of this study was to investigate what actually happens between physicians and adult patients in difficult end-of-life situations. We circulated an anonymous questionnaire to a randomized sample of 952 Swedish physicians registered in specialties comprising care of dying adult patients, 122 palliative care physicians, and 130 physicians from the Swedish Association for the Study of Pain. Of special interest were themes in conversations between the physicians and the patients, desires expressed by the patients, and actions performed by the physicians that might affect the patients' expected survival. The overall response rate was 79%. Of these, 63% of the randomized physicians, 95% of the palliative care physicians, and 43% of the Association for the Study of Pain physicians had more than occasionally treated dying adult patients during the past year. About half of them had discussed palliative care with all their dying patients, and more than half of the physicians had heard their patients expressing a wish to die. About one-third of all the physicians had given analgesic or other drugs in such doses that some of their patients' deaths were hastened. The same proportion had also been asked for active euthanasia, while 10% had been asked to assist suicide. No case of euthanasia and only a few cases of assisted suicide were reported. By implication, the study suggests that improving patients' awareness of the possibilities to relieve pain, anxiety and dyspnoea during the final days of life is an important way to reduce requests for active euthanasia.
  •  
39.
  • von Koch, L, et al. (author)
  • Rehabilitation at home after stroke: a descriptive study of an individualized intervention
  • 2000
  • In: Clinical rehabilitation. - : SAGE Publications. - 0269-2155 .- 1477-0873. ; 14:6, s. 574-583
  • Journal article (peer-reviewed)abstract
    • Objective: To describe the content of a programme involving early hospital discharge and continued rehabilitation at home after stroke. Design: Quantitative and qualitative descriptive study of an intervention within the context of a randomized controlled trial. Setting: Huddinge University Hospital, Stockholm, Sweden. Subjects: Forty-one patients, moderately impaired after stroke, rehabilitated by a team of six occupational, physical, and speech and language therapists. Results: The average duration of the programme was 14 weeks, the mean number of home visits 12, and the median total time consumption 23 hours and 20 minutes, of which face-to-face contact with the patient constituted 54%. The rehabilitation process was pursued by the patient and the therapist in partnership. Supported by the team the therapists incorporated a wider domain of activities than usual and left a considerable amount of the training to self-directed activities. The most common foci of the visits were speech and communication, ADL activities and ambulation. When planning the intervention the therapists paid attention to discrepancies between the desires and abilities of the patient on the one hand and environmental demands on the other – discrepancies detected through observation of the patient in the home environment. Conclusions: The home environment offers therapists working in a team opportunities to adopt a behaviour that enables patients with moderate neurological impairments after stroke to resume responsibility and influence over their rehabilitation process, resulting in an individualized rehabilitation programme that varies in duration, content and frequency of home visits.
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40.
  • Zetterberg, G, et al. (author)
  • Rat alveolar and interstitial macrophages in the fibrosing stage following quartz exposure
  • 2000
  • In: Human & experimental toxicology. - : SAGE Publications. - 0960-3271 .- 1477-0903. ; 19:7, s. 402-411
  • Journal article (peer-reviewed)abstract
    • Exposure to quartz induces pulmonary inflammation and development of fibrosis. In order to study the fibrosing process, we investigated morphology function and phenotype of alveolar (AMs) and interstitial (IMs) macrophages at an early stage of fibrosis in rats. Rats were exposed by intratracheal instillations of 10 mg quartz (n = 8) or saline (n = 8) and studied 3 months later. AMs were obtained by bronchoalveolar lavage and IMs by mechanical fragmentation, followed by enzymatic digestion of lung tissue. Histology revealed subacute silicosis, with early focal fibrosis and alveolar lipoproteinosis. AM quartz exposure increased phagocytic activity and expression of major histocompatibility complex (MHC) Ia antigens, the latter being associated with cellular antigen presenting capacity. IM had an even more pronounced expression of MHC than AM after quartz exposure. Both macrophage fractions had a higher expression of OX-42 (complement receptor 3, CR3) than controls, but the increase in the IM fraction might be explained by the remaining AM in the IM fraction. Exposed AM adhered less to extracellular matrix components (vitronectin and fibronectin) than controls. In contrast, the adhesion of IM to vitronectin increased after exposure. Besides increased adhesion, the effects on IM were scarce. Our results therefore do not support the hypothesis that IM has a key role in the process of inflammation, including fibrosis.
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41.
  • Aduse-Poku, Kwaku, et al. (author)
  • Expanded molecular phylogeny of the genus Bicyclus (Lepidoptera : Nymphalidae) shows the importance of increased sampling for detecting semi-cryptic species and highlights potentials for future studies
  • 2017
  • In: Systematics and Biodiversity. - : Informa UK Limited. - 1477-2000 .- 1478-0933. ; 15:2, s. 115-130
  • Journal article (peer-reviewed)abstract
    • The genus Bicyclus is one of the largest groups of African butterflies, but due to the generally cryptic nature and seasonal variation of adult wing patterns, there has been a lot of systematic confusion. With a large research community working with the model species Bicyclus anynana there has been increasing interest in the evolutionary history of the genus. A previous phylogeny started to unravel interesting patterns, but only included 61% of the then known species. With a range of new species having been described in the last decade there has been a need for an updated phylogeny for the genus. We present the most complete phylogeny of Bicyclus yet, including 93% of the currently 103 recognized species and make a range of taxonomic revisions. We revise the status of four previous subspecies and synonymized taxa that in the light of the new genetic data are raised to species level. We also subsume two subspecies and describe a new species, Bicyclus collinsi sp. nov., based on both genetic and morphological evidence. A further new taxon is identified, but not described at this point due to lack of morphological data. Our phylogeny lays a solid foundation for better understanding the evolution of Bicyclus and highlights key species-groups and complexes with intriguing ecological patterns making them prime candidates for future studies. http://zoobank.org/urn:lsid:zoobank.org:pub:2F775351-097E-4CD7-8F8F-A90B26D52DE8
  •  
42.
  • Belluardo, F., et al. (author)
  • Molecular taxonomic identification and species-level phylogeny of the narrow-mouthed frogs of the genus Rhombophryne (Anura: Microhylidae: Cophylinae) from Madagascar
  • 2022
  • In: Systematics and Biodiversity. - : Informa UK Limited. - 1477-2000 .- 1478-0933. ; 20:1, s. 1-13
  • Journal article (peer-reviewed)abstract
    • The study of diamond frogs (genus Rhombophryne, endemic to Madagascar) has been historically hampered by the paucity of available specimens, because of their low detectability in the field. Over the last 10 years, 13 new taxa have been described, and 20 named species are currently recognized. Nevertheless, undescribed diversity within the genus is probably large, calling for a revision of the taxonomic identification of published records and an update of the known distribution of each lineage. Here we generate DNA sequences of the mitochondrial 16S rRNA gene of all specimens available to us, revise the genetic data from public databases, and report all deeply divergent mitochondrial lineages of Rhombophryne identifiable from these data. We also generate a multi-locus dataset (including five mitochondrial and eight nuclear markers; 9844 bp) to infer a species-level phylogenetic hypothesis for the diversification of this genus and revise the distribution of each lineage. We recognize a total of 10 candidate species, two of which are identified here for the first time. The genus Rhombophryne is here proposed to be divided into six main species groups, and phylogenetic relationships among some of them are not fully resolved. These frogs are primarily distributed in northern Madagascar, and most species are known from only few localities. A previous record of this genus from the Tsingy de Bemaraha (western Madagascar) is interpreted as probably due to a mislabelling and should not be considered further unless confirmed by new data. By generating this phylogenetic hypothesis and providing an updated distribution of each lineage, our findings will facilitate future species descriptions, pave the way for evolutionary studies, and provide valuable information for the urgent conservation of diamond frogs.
  •  
43.
  • Bertrand, Yann, et al. (author)
  • Taxonomic surrogacy in biodiversity assessments, and the meaning of Linnaean ranks
  • 2006
  • In: Systematics and Biodiversity. ; 4:2, s. 149-159
  • Journal article (peer-reviewed)abstract
    • The majority of biodiversity assessments use species as the base unit. Recently, a series of studies have suggested replacing numbers of species with higher ranked taxa (genera, families, etc.); a method known as taxonomic surrogacy that has an important potential to save time and resources in assesments of biological diversity. We examine the relationships between taxa and ranks, and suggest that species/higher taxon exchanges are founded on misconceptions about the properties of Linnaean classification. Rank allocations in current classifications constitute a heterogeneous mixture of various historical and contemporary views. Even if all taxa were monophyletic, those referred to the same rank would simply denote separate clades without further equivalence. We conclude that they are no more comparable than any other, non-nested taxa, such as, for example, the genus Rattus and the phylum Arthropoda, and that taxonomic surrogacy lacks justification. These problems are also illustrated with data of polychaetous annelid worms from a broad-scale study of benthic biodiversity and species distributions in the Irish Sea. A recent consensus phylogeny for polychaetes is used to provide three different family-level classifications of polychaetes. We use families as a surrogate for species, and present Shannon–Wiener diversity indices for the different sites and the three different classifications, showing how the diversity measures rely on subjective rank allocations
  •  
44.
  • Cederberg, Björn (author)
  • Unveiling cryptic species of the bumblebee subgenus Bombus s. str. worldwide with COI barcodes (Hymenoptera: Apidae)
  • 2012
  • In: Systematics and Biodiversity. - : Informa UK Limited. - 1477-2000 .- 1478-0933. ; 10, s. 21-56
  • Journal article (peer-reviewed)abstract
    • Bumblebees of the subgenus Bombus s. str. dominate (or used to dominate) many north temperate pollinator assemblages and include most of the commercial bumblebee pollinator species. Several species are now in serious decline, so conservationists need to know precisely which ones are involved. The problem is that many Bombus s. str. species are cryptic, so that species identification from morphology may be impossible for some individuals and is frequently misleading according to recent molecular studies. This is the first review of the entire subgenus to: (1) avoid fixed a priori assumptions concerning the limits of the problematic species; and (2) sample multiple sites from across the entire geographic ranges of all of the principal named taxa worldwide; and (3) fit an explicit model for how characters change within an evolutionary framework; and (4) apply explicit and consistent criteria within this evolutionary framework for recognising species. We analyse easily-obtained DNA (COI-barcode) data for 559 sequences from 279 localities in 33 countries using general mixed Yule-coalescent (GMYC) models, assuming only the morphologically distinctive species B. affinis Cresson, B. franklini (Frison), B. ignitus Smith and B. tunicatus Smith, and then recognise other comparable COI-barcode groups as putative species. These species correspond to modified concepts of the taxa B. cryptarum (Fabricius), B. hypocrita Perez, B. jacobsoni Skorikov, B. lantschouensis Vogt n. stat., B. longipennis Friese, B. lucorum (Linnaeus), B. magnus Vogt, B. minshanensis Bischoff n. stat., B. occidentalis Greene, B. patagiatus Nylander, B. sporadicus Nylander, B. terrestris (Linnaeus) and B. terricola Kirby (a total of 17 species). Seven lectotypes are designated. Our results allow us for the first time to diagnose all of the putative species throughout their global ranges and to map the extent of these geographic ranges.
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45.
  •  
46.
  • Jeppson, Mikael, et al. (author)
  • European earthstars in Geastraceae (Geastrales, Phallomycetidae) – a systematic approach using morphology and molecular sequence data
  • 2013
  • In: Systematics and Biodiversity. - : Informa UK Limited. - 1477-2000 .- 1478-0933. ; 11:4, s. 437-465
  • Journal article (peer-reviewed)abstract
    • Phylogenetic relationships among European earthstars were inferred using sequence data from the nuclear ribosomal DNA internal transcribed region (ITS1, 5.8S and ITS2), partial nuclear large subunit (LSU), and partial translation elongation factor 1-alpha (Tef-α). The phylogenetic analyses recovered 11 clades that correlate to 31 morphological species and species groups. A close relationship of Myriostoma coliforme and Geastrum was supported by the molecular data. The genus Radiigera was found to be polyphyletic, and the four species were recovered in different clades within Geastrum. Radiigera bushnellii, R. flexuosa, R. fuscogleba and R. taylori are therefore combined in Geastrum. One of the supported terminal clades is likely to represent an undescribed species that occurs in east central Europe. Notes on the morphology and ecology for each species are given, including a key to the 31 species of earthstars occurring in Europe.
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47.
  •  
48.
  • Kruys, Åsa, et al. (author)
  • Phylogenetic relationships and an assessment of traditionally used taxonomic characters in the Sporormiaceae (Pleosporales, Dothideomycetes, Ascomycota), utilising multi-gene phylogenies
  • 2009
  • In: Systematics and Biodiversity. - 1477-2000 .- 1478-0933. ; 7:4, s. 465-478
  • Journal article (peer-reviewed)abstract
    • The family Sporormiaceae (Pleosporales, Dothideomycetes, Ascomycota) occur worldwide and a majority of the species are coprophilous. The taxonomy and classification of the family are based on a small number of morphological and ecological characters. Several taxa are easily confused by their shared morphological features, and the relationships between genera are poorly known and in need of critical study. The aims of this study were to resolve the phylogenetic relationships within the Sporormiaceae, test the current generic classification, and study the utility of traditional characters for the taxonomy in the group. To resolve these questions, we analysed combined data sets of ITS-nLSU rDNA, mtSSU rDNA and beta-tubulin sequences with parsimony and Bayesian methods. The results showed that many characters, which previously have been used in the taxonomy and classification of the Sporormiaceae, such as the substrate choice, presence or absence of an ostiole, and presence or absence of germ slits, were all homoplastic and not useful for circumscribing monophyletic groups. A number of characters may be useful for circumscribing smaller clades if used in combination with other features, such as the shape of the ascus with the shape of the ascospores. Our phylogenetic analyses show that Preussia and Sporormiella are non-monophyletic, and a constrained analysis forcing these genera into monophyly resulted in significantly worse trees. Spororminula is nested in Preussia s. lat., and Eremodothis and Pycnidiophora are nested within Westerdykella. Finally, we suggest a new generic classification for the family Sporormiaceae, including Sporormia, Preussia (including Sporomiella and Spororminula) and Westerdykella (including Eremodothis and Pycnidiophora). We also propose 14 new combinations: Preussia alloiomera (S.I. Ahmed & Cain) Kruys, Preussia antarctica (Speg.) Kruys, Preussia bipartis (Cain) Kruys, Preussia borealis (I.Egeland) Kruys, Preussia dubia (S.I. Ahmed & Cain) Kruys, Preussia lignicola (W. Phillips & Plowr.) Kruys, Preussia longisporopsis (S.I. Ahmed & Cain) Kruys, Preussia minipascua (S.I. Ahmed & Cain) Kruys, Preussia octomera (Auersw.) Kruys, Preussia splendens (Cain) Kruys, Preussia tenerifae (Arx & Aa) Kruys, Preussia tetramera (S.I. Ahmed & Cain) Kruys, Westerdykella angulata (A.C. Das) Kruys and Westerdykella aurantiaca (J.N. Rai & J.P. Tewari) Kruys.
  •  
49.
  • Lim, S. C., et al. (author)
  • A new genus and species of abyssal sponge commonly encrusting polymetallic nodules in the Clarion-Clipperton Zone, East Pacific Ocean
  • 2017
  • In: Systematics and Biodiversity. - : Informa UK Limited. - 1477-2000 .- 1478-0933. ; 15:6, s. 507-519
  • Journal article (peer-reviewed)abstract
    • The Clarion-Clipperton Zone (CCZ) in the East Pacific is a vast region targeted for deep-sea mineral exploration, for which there are almost no published taxonomic data. Here we describe Plenaster craigi gen. nov. sp. nov. from depths of similar to 4000 m in the eastern CCZ polymetallic nodule province. Despite over 40 years of intense exploration in the area, we reveal that P. craigi sp. nov. is the most abundant sponge and the most common metazoan encrusting on nodules in our study area at the eastern CCZ. It has a mean abundance of 15.3 +/- 8.9 individuals per m 2 across 11 stations in a 30 x 30 km study site nested within the Singapore exploration area. The white encrusting sponge is filled with spheroxyasters with occasional styles protruding the surface. Plenaster craigi sp. nov. is morphologically similar to genera from three different families in two orders: Timea (Timeidae; Tethyida); Hemiasterella and Leptosastra (Hemiasterellidae; Tethyida); and Paratimea (Stelligeridae; Axinellida). However, based on the molecular (COI and 28S) phylogenetic trees generated in this study, P. craigi sp. nov. was located in the Order Axinellida and appeared to be distant to Timea, Hemiasterella, Leptosastra, and Paratimea. We propose a new genus for our material to be placed provisionally in the family Stelligeridae, as it is the only family in the order Axinellida whose members possess euasters. This provisional placement may change when sequences of the type specimens of these genera and advanced phylogenetic reconstruction methods become available in the future. However, we have shown clearly that Plenaster gen. nov. is unique and distinct from all currently known taxa. Plenaster craigi sp. nov. being an abundant metazoan encrusting on nodule and easily identified filter-feeding animal is a potentially indicator species for future mining impacts in the eastern CCZ, and possibly across the entire CCZ.
  •  
50.
  • Luis Carballo, Jose, et al. (author)
  • Molecular and morphological data from Thoosidae in favour of the creation of a new suborder of Tetractinellida
  • 2018
  • In: Systematics and Biodiversity. - : TAYLOR & FRANCIS LTD. - 1477-2000 .- 1478-0933. ; 16:5, s. 512-521
  • Journal article (peer-reviewed)abstract
    • The Thoosidae (Porifera, Demospongiae, Tetractinellida) currently includes the genera Thoosa, Alectona, and Delectona. To this date, molecular data are only available for Alectona. In this study, the phylogenetic affinities of the genera Thoosa and Alectona have been investigated with the species T. mismalolli, T. calpulli, and T. purpurea from the Mexican Pacific using morphology and three molecular loci: the mitochondrial cytochrome oxidase subunit 1 (CO1 mtDNA), 28S rRNA (fragment D2), and 18S rRNA. Morphology and embryology showed that these genera are quite different from the rest of the tetractinellids because larvae of Alectona and Thoosa have unique features in sponges, such as the presence of monaxonic discs in Thoosa and tetraxonic discs in Alectona which disappear in the adult stages. A phylogenetic analysis using selected species from the order Tetractinellida revealed that Thoosa groups with Alectona thus confirming morphological studies. The peculiarities in spiculation and embryology of the Thoosa and Alectona larvae, which are markedly different from species belonging to the suborders Astrophorina and Spirophorina and their distant phylogenetic position (based on three molecular loci), suggest that Thoosidae could be placed in the new suborder Thoosina.
  •  
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