| 1. |
- Popat, S, et al.
(författare)
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Variation in the CTLA4/CD28 gene region confers an increased risk of coeliac disease.
- 2002
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Ingår i: Annals of human genetics. - 0003-4800 .- 1469-1809. ; 66:Pt 2, s. 125-37
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Tidskriftsartikel (refereegranskat)abstract
- Susceptibility to coeliac disease involves HLA and non-HLA-linked genes. The CTLA4/CD28 gene region encodes immune regulatory T-cell surface molecules and is a strong candidate as a susceptibility locus. We evaluated CTLA4/CD28 in coeliac disease by genetic linkage and association and combined our findings with published studies through a meta-analysis. 116 multiplex families were genotyped across CTLA4/CD28 using eight markers. The contribution of CTLA4/CD28 to coeliac disease was assessed by non-parametric linkage and association analyses. Seven studies were identified that had evaluated the relationship between CTLA4/CD28 and coeliac disease and a pooled analysis of data undertaken. In our study there was evidence for a relationship between variation in the CTLA4/CD28 region and coeliac disease by linkage and association analyses. However, the findings did not attain formal statistical significance (p = 0.004 and 0.039, respectively). Pooling findings with published results showed significant evidence for linkage (504 families) and association (940 families): p values, 0.0001 and 0.0014 at D2S2214, respectively, and 0.0008 and 0.0006 at D2S116, respectively. These findings suggest that variation in the CD28/CTLA4 gene region is a determinant of coeliac disease susceptibility. Dissecting the sequence variation underlying this relationship will depend on further analyses utilising denser sets of markers.
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| 2. |
- Högberg, Mona N., et al.
(författare)
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Contrasting patterns of soil N-cycling in model ecosystems of Fennoscandian boreal forests
- 2006
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Ingår i: Oecologia. - Berlin : Springer in cooperation with the International association for ecology (Intecol). - 0029-8549 .- 1432-1939. ; 147:1, s. 96-107
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Tidskriftsartikel (refereegranskat)abstract
- The low plant productivity of boreal forests ingeneral has been attributed to low soil N supply and lowtemperatures. Exceptionally high productivity occurs intoe-slope positions, and has been ascribed to influx of Nfrom surrounding areas and higher rates of soil Nturnover in situ. Despite large apparent natural variationsin forest productivity, rates of gross soil N mineralizationand gross nitrification have never beencompared in Fennoscandian boreal forests of contrastingproductivity. We report contrasting patterns of soilN turnover in three model ecosystems, representing therange in soil C-to-N ratios (19–41) in Fennoscandianboreal forests and differences in forest productivity by afactor close to 3. Gross N mineralization was seventimes higher when soil, microbial, and plant C-to-Nratios were the lowest compared to the highest. Thisprocess, nitrification and potential denitrification correlatedwith inorganic, total and microbial biomass N, butnot microbial C. There was a constant ratio between soiland microbial C-to-N ratio of 3.7±0.2, across wide ratiosof soil C-to-N and fungi-to-bacteria. Soil N-cyclingshould be controlled by the supplies of C and N to themicrobes. In accordance with plant allocation theory, wediscuss the possibility that the high fungal biomass athigh soil C-to-N ratio reflects a particularly high supplyof plant photosynthates, substrates of high-quality C, tomycorrhizal fungi. Methods to study soil N turnoverand N retention should be developed to take into accountthe impact of mycorrhizal fungi on soil N-cycling.
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| 3. |
- Högberg, Peter, et al.
(författare)
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High temporal resolution tracing of photosynthate carbon from the tree canopy to forest soil microorganisms
- 2008
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Ingår i: New Phytologist. - : New Phytologist Trust. - 0028-646X .- 1469-8137. ; 177:1, s. 220-228
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Tidskriftsartikel (refereegranskat)abstract
- • Half of the biological activity in forest soils is supported by recent tree photosynthate, but no study has traced in detail this flux of carbon from the canopy to soil microorganisms in the field.• Using 13CO2, we pulse-labelled over 1.5 h a 50-m2 patch of 4-m-tall boreal Pinus sylvestris forest in a 200-m3 chamber.• Tracer levels peaked after 24 h in soluble carbohydrates in the phloem at a height of 0.3 m, after 2–4 d in soil respiratory efflux, after 4–7 d in ectomycorrhizal roots, and after 2–4 d in soil microbial cytoplasm. Carbon in the active pool in needles, in soluble carbohydrates in phloem and in soil respiratory efflux had half-lives of 22, 17 and 35 h, respectively. Carbon in soil microbial cytoplasm had a half-life of 280 h, while the carbon in ectomycorrhizal root tips turned over much more slowly. Simultaneous labelling of the soil with showed that the ectomycorrhizal roots, which were the strongest sinks for photosynthate, were also the most active sinks for soil nitrogen.• These observations highlight the close temporal coupling between tree canopy photosynthesis and a significant fraction of soil activity in forests.
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| 4. |
- Keel, Sonja G., et al.
(författare)
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Allocation of carbon to fine root compounds and their residence times in a boreal forest depend on root size class and season
- 2012
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Ingår i: New Phytologist. - Malden : Wiley-Blackwell. - 0028-646X .- 1469-8137. ; 194:4, s. 972-981
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Tidskriftsartikel (refereegranskat)abstract
- Fine roots play a key role in the forest carbon balance, but their carbon dynamics remain largely unknown. We pulse labelled 50 m2 patches of young boreal forest by exposure to 13CO2 in early and late summer. Labelled photosynthates were traced into carbon compounds of < 1 and 13 mm diameter roots (fine roots), and into bulk tissue of these and first-order roots (root tips). Root tips were the most strongly labelled size class. Carbon allocation to all size classes was higher in late than in early summer; mean residence times (MRTs) in starch increased from 4 to 11 months. In structural compounds, MRTs were 0.8 yr in tips and 1.8 yr in fine roots. The MRT of carbon in sugars was in the range of days. Functional differences within the fine root population were indicated by carbon allocation patterns and residence times. Pronounced allocation of recent carbon and higher turnover rates in tips are associated with their role in nutrient and water acquisition. In fine roots, longer MRTs but high allocation to sugars and starch reflect their role in structural support and storage. Accounting for heterogeneity in carbon residence times will improve and most probably reduce the estimates of fine root production.
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| 5. |
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| 6. |
- Popat, S, et al.
(författare)
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Genome screening of coeliac disease.
- 2001
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Ingår i: Journal of Medical Genetics. - 0022-2593 .- 1468-6244. ; 39, s. 328-331
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Tidskriftsartikel (refereegranskat)
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| 7. |
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| 8. |
- Anderbrant, Olle, et al.
(författare)
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Article sex pheromone of the introduced pine sawfly, diprion similis, revisited to define a useful monitoring lure : Deviating chiral composition and behavioural responses compared to earlier reports
- 2021
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Ingår i: Insects. - : MDPI. - 2075-4450. ; 12:10
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Tidskriftsartikel (refereegranskat)abstract
- Extracts of Diprion similis females contained about 15 ng of the sex pheromone precursor 3,7‐dimethylpentadecan‐2‐ol per female. After derivatisation with (S)‐2‐acetoxypropanoyl chloride, we found that the major stereoisomer in the extract was (2S,3R,7R)‐3,7‐dimethylpentadecan‐2‐ol. Small amounts of other stereoisomers of 3,7‐dimethylpentadecan‐2‐ol were also identified in the extract, namely 1% of (2R,3S,7S), 0.3% (2R,3R,7R) and 0.4% of (2R,3R,7S). An unknown fifth substance showed a very similar spectrum to 3,7‐dimethylpentadecan‐2‐ol, both in SIM and full scan mode. None of the earlier suggested behavioural synergistic isomers ((2S,3S,7S), (2S,3S,7R) and (2S,3R,7S)) were detected in the extracts. In field tests in Ontario, Canada, the earlier identified main pheromone component, viz. the propanoate of (2S,3R,7R)‐3,7‐dimethylpentadecan‐2‐ol, was tested alone and in combination with other stereoisomers, earlier reported to be synergistic. No synergistic effects were detected and the threo four‐isomer blend was as attractive as the pure main compound. Thus, one of the few examples of a diprionid sawfly using more than one substance in its sex pheromone could not be confirmed. The results also suggest that monitoring programs can use the more easily synthesized threo‐blend without losing efficiency. Furthermore, the study suggests that other diprionid pheromones may benefit from a reinvestigation, to clarify possible synergistic effects of stereoisomers.
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| 9. |
- Anderbrant, Olle, et al.
(författare)
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Sex Pheromone of the Introduced Pine Sawfly, Diprion similis (Diprionidae), Revisited: No Activity of Earlier Reported Synergists
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Extracts of Diprion similis females were found to contain about 15 ng of the sex pheromone precursor 3,7-dimethylpentadecan-2-ol per female. When analysing the extracts after derivatisation with (2S)-2-acetoxypropionyl chloride, we found that the major stereoisomer in the extract was (2S,3R,7R)-3,7-dimethylpentadecan-2-ol. Also other stereoisomers of 3,7-dimethylpentadecan-2-ol were identified in the extract namely, 1% of (2R,3S,7S) , 0.3% (2R,3R,7R) and 0.4% of (2R,3R,7S). An unknown fifth substance showed an identical spectrum to 3,7-dimethylpentadecan-2-ol, both in SIM and full scan mode. In field tests in Ontario, Canada, the earlier identified main pheromone component, viz. the propanoate of (2S,3R,7R)-3,7-dimethylpentadecan-2-ol, was tested alone and in combination with other stereoisomers, earlier reported to be synergistic. In none of the tests were any synergistic effects detected and the threo four-isomer blend was as attractive as the pure main compound. Thus, one of the few examples of a diprionid sawfly using more than one substance in its sex pheromone could not be confirmed. The results also suggest that monitoring programs can use the more easily synthesized threo-blend without losing efficiency.
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| 10. |
- Ayas, Ebru, 1977-
(författare)
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Engineering Feelings of Quality
- 2008
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There is an increasing emphasis on developing systematical research approaches for design of products that appeal to people’s emotions and values. This thesis proposes methodological developments for investigating people’s subjective emotional needs and values towards quality and explores interactions of related physical design attributes for product design.The overall aim of the licentiate thesis is to gain an understanding on Affective engineering of products through exploring the concept of quality feeling and to develop methodological approaches for this. Quality feeling can be described as a holistic concept considering individuals’ perceptions, expectations, experiences, physical and psychological expressions for a product or service. Affective Engineering methodology aims at translating human psychological processes, such as feelings and emotions, into appropriate product design attributes, such as size, shape, and surface characteristics.The thesis presents three methodological approaches when evaluating products for affective engineering and one approach for an interactive product design support system development.The first study presented deals with feelings of quality for reach truck operator’s cabin components. Components that would convey to give a higher total quality feeling were identified and improvement opportunities were prioritized. The second study presented is based on developing an interactive affective design and decision support system software for design of the steering wheel from drivers’ individual and shared preferences. In the third study affective values arising from judgments for important feelings of quality is the study basis. The author presents research on identifying interactions of design attributes for affective values in waiting areas of primary health care services.Further, a new approach for applying Affective Engineering in design of complex contexts is proposed.The proposed approach aims to handle contexts where feelings and design attributes have complex interactions for products and services that give almost an infinite number of design alternatives that are difficult to handle in traditional Kansei Engineering studies. With this thesis also an interactive product design and decision support system software is developed for steering wheel design and proposed for educational and industrial use. The proposed system works based on linking product design attributes to human feelings by applying Genetic algorithms and provides potential basis for future product development and improvements.This thesis has also contributed with affective design recommendations applicable for vehicle cabins and waiting areas in primary health care. Moreover, a number of existing methods in Affective Engineering have been tested and methodological experience is drawn, including advantages, disadvantages and limitations of using these methods.
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