| 61. |
|
|
| 62. |
- Arnqvist, Johan, 1985-
(författare)
-
Mean Wind and Turbulence Conditions in the Boundary Layer above Forests
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- As wind turbines have grown, new installation areas become possible. Placing wind turbines in forested landscapes introduce uncertainties to the wind resource estimation. Even though close-to-canopy processes have been studied intensively during the last thirty years, the focus has mostly been on exchange processes and the height span of the studies has been below the rotor of a modern wind turbine.This thesis contains analysis of new measurements from a 138 m high tower in a forested landscape. The previous knowledge of near-canopy processes is extended to the region above the roughness sublayer. It is shown that above the roughness sublayer, the surface layer behaves as over low vegetation, and Monin-Obukhov similarity is shown to hold for several variables. However, in stable stratification, effects that could be linked to the boundary layer depth are shown to be present in the measurements. These include wind turning with height, the behaviour of the turbulence length scale and the curvature of the wind profile.Two new analytical models are presented in the thesis. One is a flux-profile expression in the roughness sublayer, which allows for analytical integration of the wind gradient. The model suggests that the roughness-sublayer effect depends on stratification and that the aerodynamic roughness length changes with stability. A decrease of roughness length in stable stratification is confirmed with a new method to determine the roughness length using measurements from the 138 m tower.The other model determines the spectral tensor in stable stratification using analytical solution to the rapid distortion equations for stratified shear flow, with homogeneous stratification and shear. By using a formulation for the integration time of the distortions of an isotropic spectrum, a model is derived which provides the cross spectra of velocity and temperature at any two given points in space.Finally the existence of waves in the wind over forests is investigated and it is concluded that the Kelvin-Helmholtz instability can create waves which are coherent in time and exist over the entire height span of wind turbine rotors. Linear wave theory is shown to be able to explain certain features of the waves.
|
|
| 63. |
- Arvidsson, Yvonne, 1960, et al.
(författare)
-
miRNA profiling of small intestinal neuroendocrine tumors defines novel molecular subtypes and identifies miR-375 as a biomarker of patient survival
- 2018
-
Ingår i: Modern Pathology. - : Elsevier BV. - 0893-3952 .- 1530-0285. ; 31, s. 1302-1317
-
Tidskriftsartikel (refereegranskat)abstract
- © 2018, United States & Canadian Academy of Pathology. The aim of this study was to define the miRNA profile of small intestinal neuroendocrine tumors and to search for novel molecular subgroups and prognostic biomarkers. miRNA profiling was conducted on 42 tumors from 37 patients who underwent surgery for small intestinal neuroendocrine tumors. Unsupervised hierarchical clustering analysis of miRNA profiles identified two groups of tumor metastases, denoted cluster M1 and M2. The smaller cluster M1 was associated with shorter overall survival and contained tumors with higher grade (WHO grade G2/3) and multiple chromosomal gains including gain of chromosome 14. Tumors of cluster M1 had elevated expression of miR-1246 and miR-663a, and reduced levels of miR-488-3p. Pathway analysis predicted Wnt signaling to be the most significantly altered signaling pathway between clusters M1 and M2. Analysis of miRNA expression in relation to tumor proliferation rate showed significant alterations including downregulation of miR-137 and miR-204-5p in tumors with Ki67 index above 3%. Similarly, tumor progression was associated with significant alterations in miRNA expression, e.g. higher expression of miR-95 and miR-210, and lower expression of miR-378a-3p in metastases. Pathway analysis predicted Wnt signaling to be altered during tumor progression, which was supported by decreased nuclear translocation of β-catenin in metastases. Survival analysis revealed that downregulation of miR-375 was associated with shorter overall survival. We performed in situ hybridization on biopsies from an independent cohort of small intestinal neuroendocrine tumors using tissue microarrays. Expression of miR-375 was found in 578/635 (91%) biopsies and survival analysis confirmed that there was a correlation between downregulation of miR-375 in tumor metastases and shorter patient survival. We conclude that miRNA profiling defines novel molecular subgroups of metastatic small intestinal neuroendocrine tumors and identifies miRNAs associated with tumor proliferation rate and progression. miR-375 is highly expressed in small intestinal neuroendocrine tumors and may be used as a prognostic biomarker.
|
|
| 64. |
|
|
| 65. |
|
|
| 66. |
- Baker, Ulrike, et al.
(författare)
-
Health workers' experiences of collaborative quality improvement for maternal and newborn care in rural Tanzanian health facilities : A process evaluation using the integrated 'Promoting Action on Research Implementation in Health Services' framework
- 2018
-
Ingår i: PLOS ONE. - : PUBLIC LIBRARY SCIENCE. - 1932-6203. ; 13:12
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Quality Improvement (OI) approaches are increasingly used to bridge the quality gap in maternal and newborn care (MNC) in Sub Saharan Africa. Health workers typically serve as both recipients and implementers of QI activities; their understanding, motivation, and level of involvement largely determining the potential effect. In support of efforts to harmonise and integrate the various QI approaches implemented in parallel in Tanzanian health facilities, our objective was to investigate how different components of a collaborative QI intervention were understood and experienced by health workers, and therefore contributed positively to its mechanisms of effect.Materials and methods: A qualitative process evaluation of a collaborative QI intervention for MNC in rural Tanzania was carried out. Semi-structured interviews were conducted with 16 health workers in 13 purposively sampled health facilities. A deductive theory-driven qualitative content analysis was employed using the integrated Promoting Action on Research Implementation in Health services (i-PARI HS) framework as a lens with its four constructs innovation, recipients, facilitation, and context as guiding themes.Results: Health workers valued the high degree of fit between QI topics and their everyday practice and appreciated the intervention's comprehensive approach. The use of run-charts to monitor progress was well understood and experienced as motivating. The importance and positive experience of on-site mentoring and coaching visits to individual health facilities was expressed by the majority of health workers. Many described the parallel implementation of various health programs as a challenge.Conclusion: Components of QI approaches that are well understood and experienced as supportive by health workers in everyday practice may enhance mechanisms of effect and result in more significant change. A focus on such components may also guide harmonisation, to avoid duplication and the implementation of parallel programs, and country ownership of QI approaches in resource limited settings.
|
|
| 67. |
- Ballardini, Natalia, et al.
(författare)
-
Development and comorbidity of eczema, asthma and rhinitis to age 12 : data from the BAMSE birth cohort
- 2012
-
Ingår i: Allergy. - Stockholm : Karolinska Institutet, Dept of Medical Epidemiology and Biostatistics. - 0105-4538 .- 1398-9995.
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Allergy-related diseases are a public health issue, but knowledge on development and comorbidity among children is scarce. The aim was to study the development of eczema, asthma and rhinitis in relation to sex and parental allergy, in a population-based cohort, during childhood. METHODS: At 1, 2, 4, 8 and 12 years, parental questionnaires were used to obtain data on allergy-related diseases. Complete data for all five follow-up occasions were available from 2916 children. Odds ratios for the risk of any allergy-related disease in relation to heredity and sex were calculated using generalized estimating equations. RESULTS: At 12 years, 58% of the children had had eczema, asthma and/or rhinitis at some time. Disease turnover was high for all three diseases throughout the study. Comorbidity increased with age, and at 12 years, 7.5% of all the children were affected by at least two allergy-related diseases. Parental allergy was associated with increased comorbidity and more persistent disease and increased the risk of having any allergy-related disease (adjusted OR 1.76; 95% CI 1.57-1.97) up to 12 years. Male sex was associated with an increased risk throughout childhood. Boys and girls did not differ in disease persistence, and for comorbidity, the differences were minor. CONCLUSIONS: Allergy-related diseases may affect a majority of children. Eczema, asthma and rhinitis develop dynamically throughout childhood, and allergic comorbidity is common. These findings indicate that allergy-related diseases should be neither seen nor studied as isolated entities.
|
|
| 68. |
- Bárcena-Uribarri, Iván, et al.
(författare)
-
P66 porins are present in both Lyme disease and relapsing fever spirochetes : a comparison of the biophysical properties of P66 porins from six Borrelia species
- 2010
-
Ingår i: Biochimica et Biophysica Acta - Biomembranes. - : Elsevier. - 0005-2736 .- 1879-2642. ; 1798:6, s. 1197-1203
-
Tidskriftsartikel (refereegranskat)abstract
- The genus Borrelia is the cause of the two human diseases: Lyme disease (LD) and relapsing fever (RF). BothLD and RF Borrelia species are obligate parasites and are dependent on nutrients provided by their hosts. Thefirst step of nutrient uptake across the outer membrane of these Gram-negative bacteria is accomplished bywater-filled channels, so-called porins. The knowledge of the porin composition in the outer membranes ofthe different pathogenic Borrelia species is limited. Only one porin has been described in relapsing feverspirochetes to date, whereas four porins are known to be present in Lyme disease agents. From these, theBorrelia burgdorferi outer membrane channel P66 is known to act as an adhesin and was well studied as aporin. To investigate if P66 porins are expressed and similarly capable of pore formation in other Borreliacausing Lyme disease or relapsing fever three LD species (B. burgdorferi, B. afzelii, B. garinii) and three RFspecies (B. duttonii, B. recurrentis and B. hermsii) were investigated for outer membrane proteins homologousto P66. A search in current published RF genomes, comprising the ones of B. duttonii, B. recurrentis and B.hermsii, indicated that they all contained P66 homologues. The P66 homologues of the six Borrelia specieswere purified to homogeneity and their pore-forming abilities as well as the biophysical properties of thepores were analyzed using the black lipid bilayer assay.
|
|
| 69. |
- Barmpatsalou, Vicky, et al.
(författare)
-
Development and validation of a porcine artificial colonic mucus model reflecting the properties of native colonic mucus in pigs
- 2023
-
Ingår i: European Journal of Pharmaceutical Sciences. - : Elsevier. - 0928-0987 .- 1879-0720. ; 181
-
Tidskriftsartikel (refereegranskat)abstract
- Colonic mucus plays a key role in colonic drug absorption. Mucus permeation assays could therefore provide useful insights and support rational formulation development in the early stages of drug development. However, the collection of native colonic mucus from animal sources is labor-intensive, does not yield amounts that allow for routine experimentation, and raises ethical concerns. In the present study, we developed an in vitro porcine artificial colonic mucus model based on the characterization of native colonic mucus. The structural properties of the artificial colonic mucus were validated against the native secretion for their ability to capture key diffusion patterns of macromolecules in native mucus. Moreover, the artificial colonic mucus could be stored under common laboratory conditions, without compromising its barrier properties. In conclusion, the porcine artificial colonic mucus model can be considered a biorelevant way to study the diffusion behavior of drug candidates in colonic mucus. It is a cost-efficient screening tool easily incorporated into the early stages of drug development and it contributes to the implementation of the 3Rs (refinement, reduction, and replacement of animals) in the drug development process.
|
|
| 70. |
- Bauer, Brigitte, 1978, et al.
(författare)
-
Modification and expulsion of keratins by human epidermal keratinocytes upon hapten exposure in vitro.
- 2011
-
Ingår i: Chemical research in toxicology. - : American Chemical Society (ACS). - 1520-5010 .- 0893-228X. ; 24:5, s. 737-43
-
Tidskriftsartikel (refereegranskat)abstract
- Allergic contact dermatitis is the most prevalent form of human immunotoxicity. It is caused by reactive low molecular weight chemicals, that is, haptens, coming in contact with the skin where hapten-peptide complexes are formed, activating the immune system. By using sensitizing fluorescent thiol-reactive haptens, that is, bromobimanes, we show how keratinocytes respond to hapten exposure in vitro and reveal, for the first time in a living system, an exact site of haptenation. Rapid internalization and reaction of haptens with keratin filaments were visualized. Subsequently, keratinocytes respond in vitro to hapten exposure by release of membrane blebs, which contain haptenated keratins 5 and 14. Particularly, cysteine 54 of K5 was found to be a specific target. A mechanism is proposed where neoepitopes, otherwise hidden from the immune system, are released after hapten exposure via keratinocyte blebbing. The observed expulsion of modified keratins by keratinocytes in vitro might play a role during hapten sensitization in vivo and should be subject to further investigations.
|
|
