| 1. |
- Abola, Benard, et al.
(författare)
-
Nonlinearly Perturbed Markov Chains and Information Networks
- 2019
-
Ingår i: Proceedings of 18th Applied Stochastic Models and Data Analysis International Conference with the Demographics 2019 Workshop, Florence, Italy: 11-14 June, 2019. - : ISAST: International Society for the Advancement of Science and Technology. - 9786185180331 ; , s. 51-79
-
Konferensbidrag (refereegranskat)abstract
- The paper is devoted to studies of perturbed Markov chains commonly used for description of information networks. In such models, the matrix of transition probabilities for the corresponding Markov chain is usually regularised by adding a special damping matrix multiplied by a small damping (perturbation) parameter ε. In this paper, we present results of the detailed perturbation analysis of Markov chains with damping component and numerical experiments supporting and illustrating the results of this perturbation analysis.
|
|
| 2. |
|
|
| 3. |
-
The Oxford Handbook of Historical Ecology and Applied Archaeology
- 2019
-
Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- This volume presents theoretical discussions, methodological outlines, and case-studies describing the discursive overlap of the theoretical and methodological framework of historical ecology, and the emerging sub-discipline of applied archaeology. Historical ecology is based on the recognition that humans are not only capable of modifying their environments, but that all environments on earth have already been directly or indirectly modified. This includes anthropogenic climate change, widespread deforestations, and species extinctions, but also very local alterations, the effects of which may last a few years, or may have legacies lasting centuries or more.The volume presents a range of case-studies that highlight how modern environments and landscapes have been shaped by humans, and includes outlines of the methods we can use to better understand these changes. Authors include anthropologists, archaeologists, human geographers, and historians, all of whom are focussed not just on defining human impacts in the past, but on the ways that understanding these changes can help inform contemporary practices and development policies. Some present examples of how ancient or current societies have modified their environments in sustainable ways, while others highlight practices that had unintended long-term consequences. The possibility of learning from these practices are discussed, as is the potential of using the long history of human resource exploitation as a method for building or testing models of future change. Rather than merely acting as advocates for historical data, the chapters collected here also warn of the limitations of drawing simple lessons from the history of interactions between humans and their environments, and note that doing so is potentially just as damaging as ignoring these rich sources of data.
|
|
| 4. |
- Agthe, Michael, 1983-
(författare)
-
Crystallization on the Mesoscale : Self-Assembly of Iron Oxide Nanocubes into Mesocrystals
- 2016
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Self-assembly of nanoparticles is a promising route to form complex, nanostructured materials with functional properties. Nanoparticle assemblies characterized by a crystallographic alignment of the nanoparticles on the atomic scale, i.e. mesocrystals, are commonly found in nature with outstanding functional and mechanical properties. This thesis aims to investigate and understand the formation mechanisms of mesocrystals formed by self-assembling iron oxide nanocubes.We have used the thermal decomposition method to synthesize monodisperse, oleate-capped iron oxide nanocubes with average edge lengths between 7 nm and 12 nm and studied the evaporation-induced self-assembly in dilute toluene-based nanocube dispersions. The influence of packing constraints on the alignment of the nanocubes in nanofluidic containers has been investigated with small and wide angle X-ray scattering (SAXS and WAXS, respectively). We found that the nanocubes preferentially orient one of their {100} faces with the confining channel wall and display mesocrystalline alignment irrespective of the channel widths. We manipulated the solvent evaporation rate of drop-cast dispersions on fluorosilane-functionalized silica substrates in a custom-designed cell. The growth stages of the assembly process were investigated using light microscopy and quartz crystal microbalance with dissipation monitoring (QCM-D). We found that particle transport phenomena, e.g. the coffee ring effect and Marangoni flow, result in complex-shaped arrays near the three-phase contact line of a drying colloidal drop when the nitrogen flow rate is high. Diffusion-driven nanoparticle assembly into large mesocrystals with a well-defined morphology dominates at much lower nitrogen flow rates. Analysis of the time-resolved video microscopy data was used to quantify the mesocrystal growth and establish a particle diffusion-based, three-dimensional growth model. The dissipation obtained from the QCM-D signal reached its maximum value when the microscopy-observed lateral growth of the mesocrystals ceased, which we address to the fluid-like behavior of the mesocrystals and their weak binding to the substrate. Analysis of electron microscopy images and diffraction patterns showed that the formed arrays display significant nanoparticle ordering, regardless of the distinctive formation process. We followed the two-stage formation mechanism of mesocrystals in levitating colloidal drops with real-time SAXS. Modelling of the SAXS data with the square-well potential together with calculations of van der Waals interactions suggests that the nanocubes initially form disordered clusters, which quickly transform into an ordered phase.
|
|
| 5. |
- Hasselgren, Malin, 1990-
(författare)
-
Dynamics of inbreeding and genetic rescue in a small population
- 2022
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Isolation at small population size can reduce individual fitness and impede population growth caused by inbreeding and genetic drift (i.e. inbreeding depression). Inbreeding depression can however be circumvented by gene flow from unrelated individuals through masking of recessive deleterious alleles and contribute to population persistence (i.e. genetic rescue). Studying these processes in natural populations across generations and under fluctuating environmental conditions however comes with major challenges. Several gaps in the knowledge thus remain regarding causes and consequences of inbreeding depression and genetic rescue in the wild. Using long term data on life history traits, combined with traditional population genetics and novel genomic techniques, we explored the dynamics of inbreeding and gene flow in the highly fragmented arctic fox (Vulpes lagopus) population in Sweden. This thesis mainly focused on the southernmost subpopulation (Helagsfjällen), previously documented to suffer from inbreeding depression. Construction of a genetically verified pedigree (Chapter I and II) revealed that gene flow from three outbred male foxes released from a captive breeding station in Norway resulted in genetic rescue, expressed as elevated first year survival and breeding success in immigrant first generation offspring (F1; Chapter I). However, the rescue effect likely only lasted for one single generation, as we found no selective advantage in later descendants of immigrants (Chapter II and IV). Whole genome sequencing of a subset of individuals from the same subpopulation showed that some immigrant F2 and F3 individuals were highly inbred despite the recent outbreeding events (Chapter III). Identification of putative deleterious variation within coding regions suggested that the immigrants introduced a large number of strongly deleterious alleles which were absent from the native gene pool (Chapter IV and V). Expression of the deleterious variation introduced may explain the low persistence of genetic rescue. We also found a negative relationship between the amount of homozygous strongly deleterious mutations and individual fitness (Chapter IV) and may be an important cause of inbreeding depression in the Swedish arctic fox. Finally, when replicating the study of genomic consequences of inbreeding and gene flow, by including an additional Swedish subpopulation (Vindelfjällen) located further north, we found contrasting patterns between the two subpopulations. While inbreeding decreased in both Helagsfjällen and Vindelfjällen following immigration, the proportion of deleterious variation increased in Helagsfjällen but not in Vindelfjällen. A potential explanation could be more regular gene flow between northern located subpopulations compared to the more geographically isolated population in Helagsfjällen, which may instead have purged a subset of strongly deleterious variation pre immigration. The results from this thesis highlight the transient nature of genetic rescue and the importance to study fitness and genetic effects of gene flow across several generations, as immigration could have negative consequences that are not manifested initially. Finally, as the effects of gene flow can be highly context dependent, demographic histories and functional genetic variation in both source and target populations should be considered before making translocation decisions for conservation purposes.
|
|
| 6. |
- Imamura, Teruhiko, et al.
(författare)
-
Successful treatment of hemodynamic compromise caused by antibody-mediated and cellular rejection in a recipient 12 years after heart transplantation
- 2013
-
Ingår i: International Heart Journal. - : International Heart Journal Association. - 1349-2365 .- 1349-3299. ; 54:5, s. 328-331
-
Tidskriftsartikel (refereegranskat)abstract
- Heart transplantation (HTx) is an established therapy for stage D heart failure due to recent advances in immunosuppressive regimens. However, antibody-mediated rejection remains an unsolved problem because of its refractoriness to standard immunosuppressive therapy with high mortality and graft loss. We experienced a 16-year old patient with hemodynamic compromise caused by both cellular and antibody-mediated rejection 12 years after HTx. The rejection was refractory to repeated steroid pulse treatment, intravenous immunoglobulin administration, and intensifying immunosuppression including addition of everolimus. Eventually, she was successfully treated with repeated plasma exchange accompanied by a single administration of the anti-CD20 monoclonal antibody rituximab.
|
|
| 7. |
- Messina, Luca, 1986-, et al.
(författare)
-
Systematic electronic-structure investigation of substitutional impurity diffusion and flux coupling in bcc iron
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The diffusion properties of a wide range of impurities (transition metals and Al, Si, and P) in ferritic alloys are here investigated by means of a combined ab initio-atomic diffusion theory approach. The flux-coupling mechanisms and the solute diffusion coefficients are inferred from electronic-structure calculations of solute-defect interactions and microscopic jump frequencies. All properties except the second nearest-neighbor binding energy are found to have a characteristic bell shape as a function of the d-band filling for the 4d and 5d series, and an M-shape for the 3d row because of the out-of-trend behavior of Mn. The solute jump frequencies are governed by compressibility, which makes diffusion of large solutes faster, although this effect is partially compensated for by lower attempt frequencies and larger correlations with the vacancy. Diffusion coefficients are predicted in a wide temperature range, far below the experimentally-accessible temperatures. In accordance with experiments, Co is found to be a slow diffuser in iron, and the same behavior is predicted for Re, Os, and Ir impurities. Finally, flux-coupling phenomena depend on the iron jump frequencies next to a solute atom, which are mainly controlled by similar electronic interactions to those determining the binding energies. Vacancy drag and solute enrichment at sinks systematically arise below a solute-dependent temperature threshold, directly correlated with the electronic-level interactions at the equilibrium and the saddle-point states. Early transition metals with repulsive second nearest-neighbor interactions also diffuse via vacancy drag, although they show a lower temperature threshold than the late metals. This confirms that drag is the most common solute-vacancy coupling mechanism in iron at low temperatures, and this is likely to be confirmed as well for impurity diffusion in other transition metals.
|
|
| 8. |
- Nicolau, Felix
(författare)
-
În contra encomionului şi a desfiinţării
- 2016. - I-VI
-
Ingår i: Actele colocviilor de critică ale Filialei Bucureşti – critică, esestică şi istorie literară a Uniunii Scriitorilor din România. - 9789731673769 ; 1, s. 37-40
-
Konferensbidrag (refereegranskat)abstract
- The brilliance and the sufferings of the literary critique in its first instance cannot be separated from the brilliance and suffering of the critic who firstly assesses the work. The question is whether the literary reviewer has become responsible only with public relations and the promotion of the book; more of a blurb generator - which means simple incandescent signaling - than analyzer.
|
|
| 9. |
- Sanner, Margareta A.
(författare)
-
Exchanging spare-parts or becoming a new person? : People's attitudes toward receiving and donating organs
- 2001
-
Ingår i: Social Science and Medicine. - : Elsevier. - 0277-9536 .- 1873-5347. ; 52:10, s. 1491-1499
-
Tidskriftsartikel (refereegranskat)abstract
- The present study explored the public's feelings and ideas about receiving organs, and how this influenced their attitudes toward accepting a transplant themselves. Also the willingness to donate was examined in order to provide a complementary perspective. The main aim was to identify consistent attitude patterns that would include attitudes toward both receiving and donating organs and the motives behind this. Sixty-nine individuals with varying socio-demographic background, selected from samples who had responded to a questionnaire on receiving and donating organs and tissues, were interviewed in-depth. The approach to analyse the interviews was hermeneutic. Seven typical attitude patterns emerged. By an ‘attitude pattern’ was meant a specific set of attitudes and motives, that formed a consistent picture that was logical and psychologically meaningful. In the discussion, two different conceptions of the body were focused. One of them meant that the body was easily objectified and conceived as machine-like, and did not represent the self. This machine model paved the way for the understanding that body parts needed to be replaced by spare parts. The other conception meant that a new organ would transfer the donor's qualities, i.e. influence the identity of the recipient with regard to behaviour, appearance, and personality. This belief may be explained by ‘analogy thinking’ based on our everday experience of how mixed entities take on the qualities of all components. Another explanation would be a kind of magical thinking and ‘the law of contagion’, which is often connected to oral incorporation. The consequences of these conceptions when patients are confronted with the factual situation of a transplantation, were discussed.
|
|
| 10. |
- Browne Mwakyanjala, Moses, et al.
(författare)
-
Functional Analysis of Software-Defined Radio Baseband for Satellite Ground Operations
- 2019
-
Ingår i: Journal of Spacecraft and Rockets. - : American Institute of Aeronautics and Astronautics. - 0022-4650 .- 1533-6794. ; 56:2, s. 458-475
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents functional analysis and system specifications of a baseband system using software-defined radio (SDR) technology. The analysis is primarily based on the latest blue-book standards from the Consultative Committee for Space Data Systems (CCSDS). It covers telemetry, telecommand, and ranging, as well as some specifications of the associated physical layers. The SDR-based baseband system is envisioned to support ground operations in the form of a software-as-a-Service (SaaS) private cloud.
|
|
