| 1. |
- Paulat, Nicole S., et al.
(författare)
-
Chiropterans Are a Hotspot for Horizontal Transfer of DNA Transposons in Mammalia
- 2023
-
Ingår i: Molecular biology and evolution. - : Oxford University Press. - 0737-4038 .- 1537-1719. ; 40:5
-
Tidskriftsartikel (refereegranskat)abstract
- Horizontal transfer of transposable elements (TEs) is an important mechanism contributing to genetic diversity and innovation. Bats (order Chiroptera) have repeatedly been shown to experience horizontal transfer of TEs at what appears to be a high rate compared with other mammals. We investigated the occurrence of horizontally transferred (HT) DNA transposons involving bats. We found over 200 putative HT elements within bats; 16 transposons were shared across distantly related mammalian clades, and 2 other elements were shared with a fish and two lizard species. Our results indicate that bats are a hotspot for horizontal transfer of DNA transposons. These events broadly coincide with the diversification of several bat clades, supporting the hypothesis that DNA transposon invasions have contributed to genetic diversification of bats.
|
|
| 2. |
- Arouca, Rodrigo, et al.
(författare)
-
Quantum Field Theory Anomalies in Condensed Matter Physics
- 2022
-
Ingår i: SciPost Physics Lecture Notes. - : Stichting SciPost. - 2590-1990.
-
Tidskriftsartikel (refereegranskat)abstract
- We give a pedagogical introduction to quantum anomalies, how they are calculated using various methods, and why they are important in condensed matter theory. We discuss axial, chiral, and gravitational anomalies as well as global anomalies. We illustrate the theory with examples such as quantum Hall liquids, Fermi liquids, Weyl semi-metals, topological insulators and topological superconductors. The required background is basic knowledge of quantum field theory, including fermions and gauge fields, and some familiarity with path integral and functional methods. Some knowledge of topological phases of matter is helpful, but not necessary.
|
|
| 3. |
|
|
| 4. |
- Benselfelt, Tobias, et al.
(författare)
-
Ion-induced assemblies of highly anisotropic nanoparticles are governed by ion-ion correlation and specific ion effects
- 2019
-
Ingår i: Nanoscale. - : Royal Society of Chemistry. - 2040-3364 .- 2040-3372. ; 11:8, s. 3514-3520
-
Tidskriftsartikel (refereegranskat)abstract
- Ion-induced assemblies of highly anisotropic nanoparticles can be explained by a model consisting of ion-ion correlation and specific ion effects: dispersion interactions, metal-ligand complexes, and local acidic environments. Films of cellulose nanofibrils and montmorillonite clay were treated with different ions, and their subsequent equilibrium swelling in water was related to important parameters of the model in order to investigate the relative importance of the mechanisms. Ion-ion correlation was shown to be the fundamental attraction, supplemented by dispersion interaction for polarizable ions such as Ca2+ and Ba2+, or metal-ligand complexes for ions such as Cu2+, Al3+ and Fe3+. Ions that form strong complexes induce local acidic environments that also contribute to the assembly. These findings are summarized in a comprehensive semi-quantitative model and are important for the design of nanomaterials and for understanding biological systems where specific ions are involved.
|
|
| 5. |
|
|
| 6. |
- Benterud, T, et al.
(författare)
-
N-Acetylcysteine Amide Exerts Possible Neuroprotective Effects in Newborn Pigs after Perinatal Asphyxia
- 2017
-
Ingår i: Neonatology. - : S. Karger AG. - 1661-7819 .- 1661-7800. ; 111:1, s. 12-21
-
Tidskriftsartikel (refereegranskat)abstract
- <b><i>Background:</i></b> Perinatal asphyxia and ensuing reoxygenation change the antioxidant capacity of cells and organs. <b><i>Objectives:</i></b> To analyze the neuroprotective effect of the antioxidant N-acetylcysteine amide (NACA) after perinatal hypoxia-reoxygenation with an emphasis on proinflammatory cytokines and the transcription factor NF-κB in the prefrontal cortex of neonatal pigs. <b><i>Methods:</i></b> Twenty-nine newborn pigs, aged 12-36 h, were subjected to global hypoxia and hypercapnia. One sham-operated group (n = 5) and 2 experimental groups (n = 12) were exposed to 8% oxygen, until the base excess was -20 mmol/l or the mean arterial blood pressure fell to <20 mm Hg (asphyxia with NACA or saline). The pigs were observed for 9.5 h after hypoxia. Samples of prefrontal cortex and plasma were analyzed. <b><i>Results:</i></b> Cortex: there was no significant difference in mRNA expression between the intervention groups regarding IL-1β, IL6, TNFα, MMP2, MMP9 or IL18. Pigs exposed to hypoxia-reoxygenation and treatment with NACA (NACA-pigs) had a significantly lower protein concentration of IL-1β than pigs treated with saline (placebo controls), i.e. 8.8 ± 3.9 versus 16.8 ± 10.5 pg/mg protein (p = 0.02). The activation of the transcription factor NF-κB (measured as the fold-change of phosphorylated p65<sup>Ser 536</sup>), was reduced in the NACA-pigs when compared to the placebo controls (5.2 ± 4.3 vs. 16.0 ± 13.5; p = 0.02). No difference between the intervention groups regarding brain histopathology or in the levels of 8-oxoguanine measured in the prefrontal cortex were observed. Plasma: the NACA-pigs had a stronger reduction of TNFα in the first 30 min following asphyxia compared with the placebo controls, i.e. 36 (30-44) versus 24 (14-32)% (p = 0.01). <b><i>Conclusion:</i></b> The reduced levels of the pivotal inflammatory markers IL-1β and TNFα and the transcription factor NF-κB may indicate that NACA has possible neuroprotective effects after perinatal asphyxia.
|
|
| 7. |
|
|
| 8. |
- Cudny, Waldemar, 1975-, et al.
(författare)
-
Monuments and their functions in urban public space
- 2019
-
Ingår i: Norsk Geografisk Tidsskrift. - : Routledge. - 0029-1951 .- 1502-5292. ; 73:5, s. 273-289
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of the article is to present and discuss functions of public monuments in relation to different dimensions of geographical space. The authors discuss public spaces, monuments, public art, based on a mixed-method approach and an analysis of scientific literature as the main research method. The theoretical discussion is supplemented with the results of Internet searches and an analysis of media supplements, and specific examples are given, including some from Poland. An additional method was autoethnography, which involved an analysis of cultural phenomena based on the authors' experience. The analysis revealed that monuments were part of public art and thus enriched public spaces in cities. They fulfilled different important functions: artistic, symbolic, commemorative, political, social, religious, marketing, and mixed. Additionally, the monuments reflected the contemporary transformation of ideas and social orders and therefore also reflected contemporary urban debates. They were products of social relations, powers, ideas, identities, and the collective memory reflected in the urban spatial structure of cities. The authors conclude that the examples presented in the demonstrate that monuments perform various functions in urban public spaces. From a spatial perspective, the role of monuments depends on their different impacts on people's perceptions and interpretations of space.
|
|
| 9. |
|
|
| 10. |
- Dehasque, Marianne, et al.
(författare)
-
Combining Bayesian age models and genetics to investigate population dynamics and extinction of the last mammoths in northern Siberia
- 2021
-
Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 259
-
Tidskriftsartikel (refereegranskat)abstract
- To understand the causes and implications of an extinction event, detailed information is necessary. However, this can be challenging when working with poorly resolved paleontological data sets. One approach to increase the data resolution is by combining different methods. In this study, we used both radiocarbon and genetic data to reconstruct the population history and extinction dynamics of the woolly mammoth in northern Siberia. We generated 88 new radiocarbon dates and combined these with previously published dates from 626 specimens to construct Bayesian age models. These models show that mammoths disappeared on the eastern Siberian mainland before the onset of the Younger Dryas (12.9–11.7 ky cal BP). Mammoths did however persist in the northernmost parts of central and western Siberia until the early Holocene. Further genetic results of 131 high quality mitogenomes, including 22 new mitogenomes generated in this study, support the hypothesis that mammoths from, or closely related to, a central and/or west- Siberian population recolonized Wrangel Island over the now submerged northern Siberian plains. As mammoths became trapped on the island due to rising sea levels, they lived another ca. 6000 years on Wrangel Island before eventually going extinct ca. 4000 years ago.
|
|
