| 1. |
- Mannerås Holm, Louise, 1980, et al.
(författare)
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Adipose tissue has aberrant morphology and function in PCOS: enlarged adipocytes and low serum adiponectin, but not circulating sex steroids, are strongly associated with insulin resistance.
- 2011
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 96:2, s. E304-11
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Tidskriftsartikel (refereegranskat)abstract
- Context: Comprehensive characterization of the adipose tissue in women with polycystic ovary syndrome (PCOS), over a wide range of body mass indices (BMIs), is lacking. Mechanisms behind insulin resistance in PCOS are unclear. Objective: To characterize the adipose tissue of women with PCOS and controls matched pair-wise for age and BMI, and to identify factors, among adipose tissue characteristics and serum sex steroids, that are associated with insulin sensitivity in PCOS. Design/Outcome Measures: Seventy-four PCOS women and 31 controls were included. BMI was 18-47 (PCOS) and 19-41 kg/m2 (controls). Anthropometric variables, volumes of subcutaneous/visceral adipose tissue (magnetic resonance imaging; MRI), and insulin sensitivity (clamp) were investigated. Adipose tissue biopsies were obtained to determine adipocyte size, lipoprotein lipase (LPL) activity, and macrophage density. Circulating testosterone, free testosterone, free 17β-estradiol, SHBG, glycerol, adiponectin, and serum amyloid A were measured/calculated. Results: Comparison of 31 pairs revealed lower insulin sensitivity, hyperandrogenemia, and higher free 17β-estradiol in PCOS. Abdominal adipose tissue volumes/distribution did not differ in the groups, but PCOS women had higher waist-to-hip ratio, enlarged adipocytes, reduced adiponectin, and lower LPL activity. In regression analysis, adipocyte size, adiponectin, and waist circumference were the factors most strongly associated with insulin sensitivity in PCOS (R2=0.681, P < 0.001). Conclusions: In PCOS, adipose tissue has aberrant morphology/function. Increased waist-to-hip ratio indicates abdominal/visceral fat accumulation, but this is not supported by MRI. Enlarged adipocytes and reduced serum adiponectin, together with a large waistline, rather than androgen excess, may be central factors in the pathogenesis/maintenance of insulin resistance in PCOS.
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| 2. |
- Andrén, Elinor, et al.
(författare)
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Medieval versus recent environmental conditions in the Baltic Proper, what was different a thousand years ago?
- 2020
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Ingår i: Palaeogeography, Palaeoclimatology, Palaeoecology. - : Elsevier. - 0031-0182 .- 1872-616X. ; 555
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Tidskriftsartikel (refereegranskat)abstract
- A sediment record from the western Gotland Basin, northwestern Baltic Proper, covering the last 1200 years, was investigated for past changes in climate and the environment using diatoms as a proxy. The aim is to compare the environmental conditions reconstructed during Medieval times with settings occurring the last century under influence of environmental stressors like eutrophication and climate change. The study core records more marine conditions in the western Gotland Basin surface waters during the Medieval Climate Anomaly (MCA; 950–1250C.E.), with a salinity of at least 8 psu compared to the present 6.5 psu. The higher salinity together with a strong summer-autumn stratification caused by warmer climate resulted in extensive long-lasting diatom blooms of Pseudosolenia calcar-avis, effectively enhancing the vertical export of organic carbon to the sediment and contributing to benthic hypoxia. Accordingly, our data support that a warm and dry climate induced the extensive hypoxic areas in the open Baltic Sea during the MCA. During the Little ice Age (LIA; 1400–1700C.E.), the study core records oxic bottom water conditions, decreasing salinity and less primary production. This was succeeded during the 20th century, about 1940, by environmental changes caused by human-induced eutrophication. Impact of climate change is visible in the diatom composition data starting about 1975C.E. and becoming more pronounced 2000C.E., visible as an increase of taxa that thrived in stratified waters during autumn blooms typically due to climate warming.
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| 3. |
- Berg, Björn, et al.
(författare)
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Decomposition rates in late stages of Scots pine and Norway spruce needle litter: Influence of nutrients and substrate properties over a climate gradient
- 2022
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Ingår i: Forest Ecology and Management. - : Elsevier. - 0378-1127 .- 1872-7042. ; 522
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this paper is to show different patterns for decomposition of the main mass of needle litter from two boreal and temperate coniferous tree species, both leading to a stabilized fraction of litter. To this purpose we have reviewed information on decomposition patterns in the lignin-dominated (late) stages of two local foliar litter types, namely those of Scots pine (Pinus silvestris) and Norway spruce (Picea abies) from two climatic gradients of equal extension. We have also reviewed factors determining the limit values for both species.Long-term decomposition studies were used to calculate annual mass loss in the lignin-dominated decomposition stage and relate these to mean annual temperature (MAT), mean annual precipitation (MAP) and concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn) and acid unhydrolyzable residue (gravimetric lignin, AUR).There was no effect of MAT on decomposition of either needle litter type. MAP had a rate-dampening effect on decomposition of Norway spruce litter. There was a rate-stimulating effect of Mn for Norway spruce litter but not for that of Scots pine. In spite of the strong negative effect of AUR and N on decomposition of Scots pine litter there was none at all for that of Norway spruce.Limit values for decomposition were related to the litters’ initial concentrations of N, Mn and AUR and differed between litter types for locally collected, natural litter and for that from experimental litter, the latter having higher N and lower Mn concentrations than the natural litter.We conclude that the two litter types have clear differences as regards rate- regulating factors for decomposition in the late lignin-dominated stage as well as for the stable fraction and suggest two different pathways for their decomposition. This is the first time that different pathways have been suggested for decomposing litter.
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| 4. |
- Berg, Björn, et al.
(författare)
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Long-term effects of climate and litter chemistry on rates and stable fractions of decomposing Scots pine and Norway spruce needle litter - A synthesis
- 2022
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Ingår i: Forests. - : MDPI. - 1999-4907 .- 1999-4907. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- We have reviewed information on early-, late- and limit-value decomposition stages for litter of Norway spruce (Picea abies) and Scots pine (Pinus silvestris). This synthesis covers c 16 studies/papers made along a climatic gradient; range in mean annual temperature (MAT) from −1 to +7 °C and mean annual precipitation (MAP) from 425 to 1070 mm. Scots pine has an early stage dominated by carbohydrate decomposition and a late stage dominated by decomposition of lignin; Norway spruce has just one stage dominated by lignin decomposition. We used data for annual mass loss to identify rate-regulating factors in both stages; climate data, namely, MAT and MAP, as well as substrate properties, namely, nitrogen (N), acid unhydrolyzable residue (AUR), manganese (Mn). Early-stage decomposition for Scots pine litter was dominated positively by MAT; the late stage was dominated negatively by MAT, N, and AUR, changing with decomposition stage; there was no effect of Mn. Norway spruce litter had no early stage; decomposition in the lignin-dominated stage was mainly negative to MAP, a negative relationship to AUR and non-significant relationships to N and MAT. Mn had a positive relationship. Limit values for decomposition, namely, the accumulated mass loss at which decomposition is calculated to be zero, were related positively to Mn and AUR for Scots pine litter and negatively to AUR for Norway spruce litter. With different sets of rate-regulating factors as well as different compounds/elements related to the limit values, the decomposition patterns or pathways are different.
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| 5. |
- Berg, Björn, 1943-, et al.
(författare)
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Magnesium dynamics in decomposing foliar litter - a synthesis
- 2021
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Ingår i: Geoderma. - : Elsevier. - 0016-7061 .- 1872-6259. ; 382
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Tidskriftsartikel (refereegranskat)abstract
- We synthesized available data for magnesium (Mg) dynamics in newly shed and decomposing foliar litter of mainly pine (Pinus) species, Norway spruce (Picea abies), and birch (Betula) species. Using original, measured data from 40 stands organized in climatic gradients we intended to determine patterns of Mg concentration and net release vs accumulated mass loss of the litter. This synthesis is likely the first synthesis of Mg dynamics in decomposing litter.In paired stands, litter of both Norway spruce and lodgepole pine (Pinus contorta) had higher Mg concentrations than Scots pine (Pinus silvestris), with concentrations in Norway spruce litter even twice as high.In decomposing litter, Mg concentrations followed a quadratic (X2-X) function vs accumulated mass loss and consequently had minima, different for Norway spruce and Scots pine litter. Out of 68 decomposition studies 53 gave minimum concentration. The Mg minimum concentration during decomposition was positively related to initial Mg concentration for Scots pine and Scots pine plus lodgepole pine but not for Norway spruce. The increase in concentration suggests that after the minimum Mg was temporarily limiting.For Norway spruce litter there was a relationship between minimum concentration of Mg and the limit value. There was no such relationship for Scots pine and not for the combined pine data.Magnesium net release started directly after the incubation and was linear to accumulated mass loss of litter, giving a slope coefficient (release rate) for each study. The net release rate was linear to initial Mg concentration and all studies combined gave a negative linear relationship.
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| 6. |
- Berry, Max, 1969, et al.
(författare)
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Endovascular training with animals versus virtual reality systems: an economic analysis
- 2008
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Ingår i: J Vasc Interv Radiol. - : Elsevier BV. - 1051-0443. ; 19:2 Pt 1, s. 233-8
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To assess the relative costs of a virtual reality (VR) laboratory and an animal laboratory for endovascular skills training. MATERIALS AND METHODS: Cost data extracted from a previous experiment was used to perform a financial analysis according to the guidelines published by the National Institutes of Health. The analysis compared the purchase or rental of a Procedicus Vascular Interventional System Trainer to the rental of an animal laboratory. RESULTS: The VR laboratory course cost $3,434 per trainee versus $4,634 in the animal laboratory according to the purchase-versus-rental analysis. The cost ratio was 0.74 in favor of the VR laboratory. Cost ratio sensitivity analysis ranged from 0.25 in favor of the VR laboratory to 2.22 in favor of the animal laboratory. The first-year potential savings were $62,410 assuming exclusive use of the VR laboratory. The 5-year training savings totaled $390,376, excluding the $60,000 residual value of the simulator. Simulator rental reduced the course price to $1,076 per trainee and lowered the cost ratio to 0.23 in favor of the VR laboratory. Findings of sensitivity analysis ranged from 0.08 to 0.70 in favor of the VR laboratory. The first-year and 5-year potential national savings increased to $185,026 and $1,013,238, respectively. CONCLUSIONS: Although evidence remains sparse that the training of interventional skills in artificial environments translates to better performance in human procedures, there are good pedagogic grounds on which to believe that such training will become increasingly important. The present comparison of the direct costs of two such models suggests that VR training is less expensive than live animal training.
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| 7. |
- Bommarco, Riccardo, et al.
(författare)
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Genetic and phenotypic differences between thistle populations in response to habitat and weed management practices
- 2010
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Ingår i: Biological Journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4066 .- 1095-8312. ; 99:4, s. 797-807
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Tidskriftsartikel (refereegranskat)abstract
- Rapid evolutionary change is increasingly being recognized as commonplace, but the evolutionary consequences for species and ecosystems under human-induced selection regimes have not been explored in detail, although many species occur in such environments. In a common garden experiment and with amplified fragment length polymorphism markers, we examined whether genetic differentiation has taken place between spatially intermixed populations of creeping thistles Cirsium arvense (Asteraceae) collected from a natural habitat (maritime shores), a semi-natural habitat (road verges) and arable fields under two management regimes: conventional and organic farming. Populations of C. arvense have altered genetically and locally adapted their growth patterns with changed land use. Although plants from different habitats showed similar total biomass production, shoot and root production was higher for maritime populations, suggesting selection for increased competitive ability. Competitive ability then declined in the order semi-natural, conventional farms and organic farms. Thistles in arable fields may be more selected for tolerance against disturbances from herbicides and mechanical weed control. In addition, early shoot sprouting and genetic analysis showed differentiation between plants originating from conventional farms and farms that were converted to organic 9–30 years ago, suggesting some adaptation to altered crop cultivation practices
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| 8. |
- Carpio, Antonio J., et al.
(författare)
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Wild boar effects on fungal abundance and guilds from sporocarp sampling in a boreal forest ecosystem
- 2022
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Ingår i: Animals. - : MDPI. - 2076-2615. ; 12:19
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Tidskriftsartikel (refereegranskat)abstract
- Native wild boar (Sus scrofa) populations are expanding across Europe. This is cause for concern in some areas where overabundant populations impact natural ecosystems and adjacent agronomic systems. To better manage the potential for impacts, managers require more information about how the species may affect other organisms. For example, information regarding the effect of wild boar on soil fungi for management application is lacking. Soil fungi play a fundamental role in ecosystems, driving essential ecological functions; acting as mycorrhizal symbionts, sustaining plant nutrition and providing defense; as saprotrophs, regulating the organic matter decomposition; or as plant pathogens, regulating plant fitness and survival. During autumn (Sep–Nov) 2018, we investigated the effects of wild boar (presence/absence and rooting intensity) on the abundance (number of individuals) of fungal sporocarps and their functional guilds (symbiotic, saprotrophic and pathogenic). We selected eleven forested sites (400–500 × 150–200 m) in central Sweden; six with and five without the presence of wild boar. Within each forest, we selected one transect (200 m long), and five plots (2 × 2 m each) for sites without wild boar, and ten plots for sites with boars (five within and five outside wild boar disturbances), to determine the relationship between the intensity of rooting and the abundance of sporocarps for three fungal guilds. We found that the presence of wild boar and rooting intensity were associated with the abundance of sporocarps. Interestingly, this relationship varied depending on the fungal guild analyzed, where wild boar rooting had a positive correlation with saprophytic sporocarps and a negative correlation with symbiotic sporocarps. Pathogenic fungi, in turn, were more abundant in undisturbed plots (no rooting) but located in areas with the presence of wild boar. Our results indicate that wild boar activities can potentially regulate the abundance of fungal sporocarps, with different impacts on fungal guilds. Therefore, wild boar can affect many essential ecosystem functions driven by soil fungi in boreal forests, such as positive effects on energy rotation and in creating mineral availability to plants, which could lead to increased diversity of plants in boreal forests.
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| 9. |
- Chen, DeJiu, et al.
(författare)
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Model integration in the development of embedded control systems - A characterization of current research efforts
- 2006
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Ingår i: 2006 IEEE Conference on Computer-Aided Control System Design, Vols 1 and 2. - : IEEE conference proceedings. - 9780780397972 ; , s. 283-289
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Konferensbidrag (refereegranskat)abstract
- The design of advanced embedded control systems requires a systematic approach in handling their increasing complexity and in particular integration of the different aspects and parts of a product worked on by different experts. Several variants of model-based approaches are today advocated to facilitate systems integration. This paper describes a number of representative efforts that address multiple concerns or views including modeling languages such as AADL and EAST-ADL as well as model integration environments such as GeneralStore, ToolNet, and Fujaba. We present a characterization of the approaches and thereby highlight their commonalities and differences regarding basic integration mechanisms and engineering support. We conclude with a prospect for future work.
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