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2.
  • Blunden, Jessica, et al. (author)
  • State of the Climate in 2012
  • 2013
  • In: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 94:8, s. S1-S258
  • Journal article (peer-reviewed)abstract
    • For the first time in serveral years, the El Nino-Southern Oscillation did not dominate regional climate conditions around the globe. A weak La Ni a dissipated to ENSOneutral conditions by spring, and while El Nino appeared to be emerging during summer, this phase never fully developed as sea surface temperatures in the eastern conditions. Nevertheless, other large-scale climate patterns and extreme weather events impacted various regions during the year. A negative phase of the Arctic Oscillation from mid-January to early February contributed to frigid conditions in parts of northern Africa, eastern Europe, and western Asia. A lack of rain during the 2012 wet season led to the worst drought in at least the past three decades for northeastern Brazil. Central North America also experienced one of its most severe droughts on record. The Caribbean observed a very wet dry season and it was the Sahel's wettest rainy season in 50 years. Overall, the 2012 average temperature across global land and ocean surfaces ranked among the 10 warmest years on record. The global land surface temperature alone was also among the 10 warmest on record. In the upper atmosphere, the average stratospheric temperature was record or near-record cold, depending on the dataset. After a 30-year warming trend from 1970 to 1999 for global sea surface temperatures, the period 2000-12 had little further trend. This may be linked to the prevalence of La Ni a-like conditions during the 21st century. Heat content in the upper 700 m of the ocean remained near record high levels in 2012. Net increases from 2011 to 2012 were observed at 700-m to 2000-m depth and even in the abyssal ocean below. Following sharp decreases in to the effects of La Ni a, sea levels rebounded to reach records highs in 2012. The increased hydrological cycle seen in recent years continued, with more evaporation in drier locations and more precipitation in rainy areas. In a pattern that has held since 2004, salty areas of the ocean surfaces and subsurfaces were anomalously salty on average, while fresher areas were anomalously fresh. Global tropical cyclone activity during 2012 was near average, with a total of 84 storms compared with the 1981-2010 average of 89. Similar to 2010 and 2011, the North Atlantic was the only hurricane basin that experienced above-normal activity. In this basin, Sandy brought devastation to Cuba and parts of the eastern North American seaboard. All other basins experienced either near-or below-normal tropical cyclone activity. Only three tropical cyclones reached Category 5 intensity-all in Bopha became the only storm in the historical record to produce winds greater than 130 kt south of 7 N. It was also the costliest storm to affect the Philippines and killed more than 1000 residents. Minimum Arctic sea ice extent in September and Northern Hemisphere snow cover extent in June both reached new record lows. June snow cover extent is now declining at a faster rate (-17.6% per decade) than September sea ice extent (-13.0% per decade). Permafrost temperatures reached record high values in northernmost Alaska. A new melt extent record occurred on 11-12 July on the Greenland ice sheet; 97% of the ice sheet showed some form of melt, four times greater than the average melt for this time of year. The climate in Antarctica was relatively stable overall. The largest maximum sea ice extent since records begain in 1978 was observed in September 2012. In the stratosphere, warm air led to the second smallest ozone hole in the past two decades. Even so, the springtime ozone layer above Antarctica likely will not return to its early 1980s state until about 2060. Following a slight decline associated with the global 2 emissions from fossil fuel combustion and cement production reached a record 9.5 +/- 0.5 Pg C in 2011 and a new record of 9.7 +/- 0.5 Pg C is estimated for 2012. Atmospheric CO2 concentrations increased by 2.1 ppm in 2012, to 392.6 ppm. In spring 2012, 2 concentration exceeded 400 ppm at 7 of the 13 Arctic observation sites. Globally, other greenhouse gases including methane and nitrous oxide also continued to rise in concentration and the combined effect now represents a 32% increase in radiative forcing over a 1990 baseline. Concentrations of most ozone depleting substances continued to fall.
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3.
  • Caesar, C., et al. (author)
  • Beyond the neutron drip line: The unbound oxygen isotopes O-25 and O-26
  • 2013
  • In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993 .- 0556-2813. ; 88:3
  • Journal article (peer-reviewed)abstract
    • The very neutron-rich oxygen isotopes O-25 and O-26 are investigated experimentally and theoretically. The unbound states are populated in an experiment performed at the R3B-LAND setup at GSI via proton-knockout reactions from F-26 and F-27 at relativistic energies around 442 and 414 MeV/nucleon, respectively. From the kinematically complete measurement of the decay into O-24 plus one or two neutrons, the O-25 ground-state energy and width are determined, and upper limits for the O-26 ground-state energy and lifetime are extracted. In addition, the results provide indications for an excited state in O-26 at around 4 MeV. The experimental findings are compared to theoretical shell-model calculations based on chiral two- and three-nucleon (3N) forces, including for the first time residual 3N forces, which are shown to be amplified as valence neutrons are added.
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4.
  • Heine, M., et al. (author)
  • Determination of the neutron-capture rate of C-17 for r-process nucleosynthesis
  • 2017
  • In: Physical Review C. - 2469-9985 .- 2469-9993. ; 95:1, s. Article no 014613 -
  • Journal article (peer-reviewed)abstract
    • With the (RB)-B-3-LAND setup at GSI we have measured exclusive relative-energy spectra of the Coulomb dissociation of C-18 at a projectile energy around 425A MeV on a lead target, which are needed to determine the radiative neutron-capture cross sections of C-17 into the ground state of C-18. Those data have been used to constrain theoretical calculations for transitions populating excited states in C-18. This allowed to derive the astrophysical cross section sigma(n gamma)*. accounting for the thermal population of C-17 target states in astrophysical scenarios. The experimentally verified capture rate is significantly lower than those of previously obtained Hauser-Feshbach estimations at temperatures T-9
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5.
  • Raghavan, Maanasa, et al. (author)
  • The genetic prehistory of the New World Arctic
  • 2014
  • In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 345:6200, s. 1020-
  • Journal article (peer-reviewed)abstract
    • The New World Arctic, the last region of the Americas to be populated by humans, has a relatively well-researched archaeology, but an understanding of its genetic history is lacking. We present genome-wide sequence data from ancient and present-day humans from Greenland, Arctic Canada, Alaska, Aleutian Islands, and Siberia. We show that Paleo-Eskimos (similar to 3000 BCE to 1300 CE) represent a migration pulse into the Americas independent of both Native American and Inuit expansions. Furthermore, the genetic continuity characterizing the Paleo-Eskimo period was interrupted by the arrival of a new population, representing the ancestors of present-day Inuit, with evidence of past gene flow between these lineages. Despite periodic abandonment of major Arctic regions, a single Paleo-Eskimo metapopulation likely survived in near-isolation for more than 4000 years, only to vanish around 700 years ago.
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6.
  • Reifarth, R., et al. (author)
  • Nuclear astrophysics with radioactive ions at FAIR
  • 2016
  • In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 665:1
  • Conference paper (peer-reviewed)abstract
    • The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process beta-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes.
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7.
  • Röder, M., et al. (author)
  • Coulomb dissociation of 20,21 N
  • 2016
  • In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993 .- 0556-2813. ; 93:6
  • Journal article (peer-reviewed)abstract
    • Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N20,21 are reported. Relativistic N20,21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a kinematically complete experiment. Using the detailed balance theorem, the N19(n,γ)N20 and N20(n,γ)N21 excitation functions and thermonuclear reaction rates have been determined. The N19(n,γ)N20 rate is up to a factor of 5 higher at T
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8.
  • Thies, Ronja, 1987, et al. (author)
  • Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes
  • 2016
  • In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993 .- 0556-2813. ; 93:5
  • Journal article (peer-reviewed)abstract
    • Models describing nuclear fragmentation and fragmentation fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool for reaching the most neutron-rich nuclei, creating a need for models to describe also these reactions. Purpose: We want to extend the presently available data on fragmentation reactions towards the light exotic region on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentation especially for unstable isotopes. Method: We have measured projectile fragments from C10,12-18 and B10-15 isotopes colliding with a carbon target. These measurements were all performed within one experiment, which gives rise to a very consistent data set. We compare our data to model calculations. Results: One-proton removal cross sections with different final neutron numbers (1pxn) for relativistic C10,12-18 and B10-15 isotopes impinging on a carbon target. Comparing model calculations to the data, we find that the epax code is not able to describe the data satisfactorily. Using abrabla07 on the other hand, we find that the average excitation energy per abraded nucleon needs to be decreased from 27 MeV to 8.1 MeV. With that decrease abrabla07 describes the data surprisingly well. Conclusions: Extending the available data towards light unstable nuclei with a consistent set of new data has allowed a systematic investigation of the role of the excitation energy induced in projectile fragmentation. Most striking is the apparent mass dependence of the average excitation energy per abraded nucleon. Nevertheless, this parameter, which has been related to final-state interactions, requires further study.
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9.
  • Adalbjörnsson, Stefan Ingi, et al. (author)
  • Sparse Localization of Harmonic Audio Sources
  • 2016
  • In: IEEE/ACM Transactions on Audio, Speech, and Language Processing. - 2329-9290. ; 24:1, s. 117-129
  • Journal article (peer-reviewed)abstract
    • In this paper, we propose a novel method for estimating the locations of near- and/or far-field harmonic audio sources impinging on an arbitrary, but calibrated, sensor array. Using a joint pitch and location estimation formed in two steps, we first estimate the fundamental frequencies and complex amplitudes under a sinusoidal model assumption, whereafter the location of each source is found by utilizing both the difference in phase and the relative attenuation of the magnitude estimates. As audio recordings often consist of multi-pitch signals exhibiting some degree of reverberation, where both the number of pitches and the source locations are unknown, we propose to use sparse heuristics to avoid the necessity of detailed a priori assumptions on the spectral and spatial model orders. The method’s performance is evaluated using both simulated and measured audio data, with the former showing that the proposed method achieves near-optimal performance, whereas the latter confirms the method’s feasibility when used with real recordings.
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10.
  • Aleklett, Kjell, et al. (author)
  • The Peak of the Oil Age : Analyzing the world oil production Reference Scenario in World Energy Outlook 2008
  • 2010
  • In: Energy Policy. - Oxford : Elsevier Ltd. - 0301-4215 .- 1873-6777. ; 38:3, s. 1398-1414
  • Journal article (peer-reviewed)abstract
    • The assessment of future global oil production presented in the IEA’s World Energy Outlook 2008 (WEO 2008) is divided in to 6 fractions; four relate to crude oil, one to non-conventional oil, and the final fraction is natural-gas-liquids (NGL). Using the production parameter, depletion-rate-of-recoverable- resources, we have analyzed the four crude oil fractions and found that the 75 Mb/d of crude oil production forecast for year 2030 appears significantly overstated, and is more likely to be in the region of 55 Mb/d. Moreover, an alysis of the other fractions strongly suggests lower than expected production levels. In total, our analysis points to a world oil supply in 2030 of 75Mb/d, some 26 Mb/d lower than the IEA predicts. The connection between economic growth and energy use is fundamental in the IEA’s present modeling approach. Since our forecast sees little chance of a significant increase in global oil production, our findings suggest that the ‘‘policy makers, investors and end users’’ to whom WEO 2008 is addressed should rethink their future plans for economic growth. The fact that global oil production has very probably passed its maximum implies that we have reached the Peak of the Oil Age.
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11.
  • Altstadt, S.G., et al. (author)
  • B-13,B-14(n,gamma) via Coulomb Dissociation for Nucleosynthesis towards the r-Process
  • 2014
  • In: Nuclear Data Sheets. - : Elsevier BV. - 1095-9904 .- 0090-3752. ; 120, s. 197-200
  • Conference paper (peer-reviewed)abstract
    • Radioactive beams of 14,15B produced by fragmentation of a primary 40Ar beam were directed onto a Pb target to investigate the neutron breakup within the Coulomb field. The experiment was performed at the LAND/R3B setup. Preliminary results for the Coulomb dissociation cross sections as well as for the astrophysically interesting inverse reactions, 13,14B(n,γ), are presented.
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12.
  • Alves, Isabel, et al. (author)
  • Human genetic structure in Northwest France provides new insights into West European historical demography
  • 2024
  • In: Nature Communications. - : Springer Nature. - 2041-1723. ; 15
  • Journal article (peer-reviewed)abstract
    • The demographical history of France remains largely understudied despite its central role toward understanding modern population structure across Western Europe. Here, by exploring publicly available Europe-wide genotype datasets together with the genomes of 3234 present-day and six newly sequenced medieval individuals from Northern France, we found extensive fine-scale population structure across Brittany and the downstream Loire basin and increased population differentiation between the northern and southern sides of the river Loire, associated with higher proportions of steppe vs. Neolithic-related ancestry. We also found increased allele sharing between individuals from Western Brittany and those associated with the Bell Beaker complex. Our results emphasise the need for investigating local populations to better understand the distribution of rare (putatively deleterious) variants across space and the importance of common genetic legacy in understanding the sharing of disease-related alleles between Brittany and people from western Britain and Ireland.
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13.
  • Auffret, Alistair G., et al. (author)
  • HistMapR : Rapid digitization of historical land-use maps in R
  • 2017
  • In: Methods in Ecology and Evolution. - 2041-210X. ; 8:11, s. 1453-1457
  • Journal article (peer-reviewed)abstract
    • Habitat destruction and degradation represent serious threats to biodiversity, and quantification of land-use change over time is important for understanding the consequences of these changes to organisms and ecosystem service provision. Comparing land use between maps from different time periods allows estimation of the magnitude of habitat change in an area. However, digitizing historical maps manually is time-consuming and analyses of change are usually carried out at small spatial extents or at low resolutions. HistMapR contains a number of functions that can be used to semi-automatically digitize historical land use according to a map's colours, as defined by the RGB bands of the raster image. We test the method on different historical land-use map series and compare results to manual digitizations. Digitization is fast, and agreement with manually digitized maps of around 80-90% meets common targets for image classification. We hope that the ability to quickly classify large areas of historical land use will promote the inclusion of land-use change into analyses of biodiversity, species distributions and ecosystem services.
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14.
  • Bernes, Claes, et al. (author)
  • How are biodiversity and dispersal of species affected by the management of roadsides? A systematic map
  • 2017
  • In: Environmental Evidence. - : Springer Science and Business Media LLC. - 2047-2382. ; 6:1
  • Journal article (peer-reviewed)abstract
    • Background: In many parts of the world, roadsides are regularly managed for traffic-safety reasons. Hence, there are similarities between roadsides and certain other managed habitats, such as wooded pastures and mown or grazed grasslands. These habitats have declined rapidly in Europe during the last century. For many species historically associated with them, roadsides may function as new primary habitats or as dispersal corridors in fragmented landscapes. Current recommendations for roadside management to promote conservation values are largely based on studies of plants in semi-natural grasslands, although such areas often differ from roadsides in terms of environmental conditions and disturbance regimes. Moreover, roadsides provide habitat not only for plants but also for many insects. For these reasons, stakeholders in Sweden have emphasised the need for more targeted management recommendations, based on actual studies of roadside biodiversity. Methods: This systematic map provides an overview of the available evidence on how biodiversity is affected by various forms of roadside management, and how such management influences the dispersal of species along roads or roadsides. We searched for literature using 13 online publication databases, 4 search engines, 36 specialist websites and 5 literature reviews. Search terms were developed in English, Danish, Dutch, French, German, Norwegian, Spanish and Swedish. Identified articles were screened for relevance using criteria set out in a protocol. No geographical restrictions were applied, and all species and groups of organisms were considered. Descriptions of included studies are available in an Excel file, and also in an interactive GIS application that can be accessed at an external website. Results: Our searches identified more than 7000 articles. The 207 articles included after screening described 301 individual studies considered to be relevant. More than two-thirds of these studies were conducted in North America, with most of the rest performed in Europe. More than half of the studies were published in grey literature such as reports from agencies or consultants. The interventions most commonly studied were herbicide use, sowing and mowing, followed by soil amendments such as mulching and fertiliser additions. The outcomes most frequently reported were effects of interventions on the abundance or species richness of herbs/forbs, graminoids and woody plants. Effects on insects and birds were reported in 6 and 3% of the studies, respectively. Conclusions: This systematic map is based on a comprehensive and systematic screening of all available literature on the effects of roadside management on biodiversity and dispersal of species. As such it should be of value to a range of actors, including managers and policymakers. The map provides a key to finding concrete guidance for conservation- and restoration-oriented roadside management from published research. However, the map also highlights important knowledge gaps: little data was found for some geographical regions, research is heavily biased taxonomically towards plants, and no study was found on how species dispersal was affected by roadside management. The map could therefore be a source of inspiration for new research.
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15.
  • Bernes, Claes, et al. (author)
  • How are biodiversity and dispersal of species affected by the management of roadsides? A systematic map protocol
  • 2016
  • In: Environmental Evidence. - : Springer Science and Business Media LLC. - 2047-2382. ; 5:4
  • Journal article (peer-reviewed)abstract
    • Background: In many parts of the world, roadsides are regularly managed for traffic-safety reasons. Hence, there are similarities between roadsides and certain other managed habitats, such as wooded pastures and mown or grazed grasslands. In contrast to roadsides, the latter habitats have declined rapidly in Europe during the last century, and today only a fraction of their former extent remains. For many species historically associated with these habitats, roadsides may therefore function as new primary habitats or as dispersal corridors in fragmented landscapes. Current recommendations for roadside management to promote conservation values are largely based on studies of plants in semi-natural grasslands, although such areas often differ from roadsides in terms of environmental factors and impacts. Moreover, roadsides provide habitats not only for plants but also for many insects, especially if they are sandy and exposed to the sun. For these reasons, stakeholders in Sweden have emphasised the need for more targeted management recommendations, based on actual studies of roadside biodiversity. Methods: The proposed systematic map is intended to provide an overview of the available evidence on how biodiversity is affected by various forms of roadside management, and how such management influences the dispersal of species along roads or roadsides. Relevant interventions include e.g. mowing, shrub removal, control of invasive/nuisance species, sowing or planting, burning, grazing by livestock, scraping and ditching. Non-intervention or alternative forms of roadside management will be used as comparators. Relevant outcomes include measures of species or genetic diversity, the abundance of individual species or groups of organisms, species distribution patterns, and movement rates of individuals or propagules. Searches will be made for peer-reviewed and grey literature in English and several other languages. No geographical restrictions will be applied, and all species and species groups will be considered.
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16.
  • Bernes, Claes, et al. (author)
  • How does roadside vegetation management affect the diversity of vascular plants and invertebrates? A systematic review protocol
  • 2017
  • In: Environmental Evidence. - : Springer Science and Business Media LLC. - 2047-2382. ; 6:1
  • Research review (peer-reviewed)abstract
    • Background: Roadsides have been acknowledged as potential substitutes for semi-natural grasslands and other open habitats with high biodiversity, many of which are now declining. Current recommendations for roadside management to promote conservation of biodiversity are largely based on studies of plants in meadows or pastures, although such areas often differ from roadsides in terms of environmental conditions and disturbance regimes. Stakeholders in Sweden have emphasised the need for more targeted guidelines for roadside management, based on actual roadside studies. We recently performed a systematic mapping of the evidence on how roadside management affects biodiversity and the dispersal of species. Through this process, we found 98 studies on how the richness or abundance of species on roadsides is affected by management such as regular mowing, burning, grazing or selective mechanical removal of plants. Since all of these interventions entail removal of plant biomass, they are comparable. Most of the studies recorded management effects on vascular plants, but there were 14 investigations of insects and other invertebrates. We now intend to proceed with a full systematic review of how maintenance or restoration of roadsides based on non-chemical vegetation removal affects the diversity of vascular plants and invertebrates. Methods: Most of the evidence on which the proposed systematic review is to be based will be selected from the systematic map. To identify more recently published literature on the topic of the review, we will perform a search update using a subset of the search terms applied for the systematic map. The criteria for inclusion of studies will be the same as for the map, except that interventions and outcomes will be restricted to those relevant to the review. Relevant studies will be subject to critical appraisal and categorised as having high or low validity for the review. Studies with low validity will be excluded from the review. Utilisable data on outcomes, interventions and other potential effect modifiers will be extracted from included articles. A narrative synthesis will describe the validity and findings of all studies in the review. Where a sufficient number of studies report similar outcome types, meta-analysis will be conducted.
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17.
  • Bhandage, Amol K., et al. (author)
  • GABAergic signaling in human and murine NK cells upon challenge with Toxoplasma gondii
  • 2021
  • In: Journal of Leukocyte Biology. - : Oxford University Press (OUP). - 0741-5400 .- 1938-3673. ; 110:4, s. 617-628
  • Journal article (peer-reviewed)abstract
    • Protective cytotoxic and proinflammatory cytokine responses by NK cells impact the outcome of infections by Toxoplasma gondii, a common parasite in humans and other vertebrates. However, T. gondii can also sequester within NK cells and downmodulate their effector functions. Recently, the implication of GABA signaling in infection and inflammation-related responses of mononuclear phagocytes and T cells has become evident. Yet, the role of GABAergic signaling in NK cells has remained unknown. Here, we report that human and murine NK cells synthesize and secrete GABA in response to infection challenge. Parasitized NK cells secreted GABA, whereas activation stimuli, such as IL-12/IL-18 or parasite lysates, failed to induce GABA secretion. GABA secretion by NK cells was associated to a transcriptional up-regulation of GABA synthesis enzymes (glutamate decarboxylases [GAD65/67]) and was abrogated by GAD inhibition. Further, NK cells expressed GABA-A receptor subunits and GABA signaling regulators, with transcriptional modulations taking place upon challenge with T. gondii. Exogenous GABA and GABA-containing supernatants from parasitized dendritic cells (DCs) impacted NK cell function by reducing the degranulation and cytotoxicity of NK cells. Conversely, GABA-containing supernatants from NK cells enhanced the migratory responses of parasitized DCs. This enhanced DC migration was abolished by GABA-A receptor antagonism or GAD inhibition and was reconstituted by exogenous GABA. Jointly, the data show that NK cells are GABAergic cells and that GABA hampers NK cell cytotoxicity in vitro. We hypothesize that GABA secreted by parasitized immune cells modulates the immune responses to T. gondii infection.
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18.
  • Cortina-Gil, D., et al. (author)
  • CALIFA, a Dedicated Calorimeter for the R3B/FAIR
  • 2014
  • In: Nuclear Data Sheets. - : Elsevier BV. - 1095-9904 .- 0090-3752. ; 120, s. 99-101
  • Journal article (peer-reviewed)abstract
    • The R3B experiment (Reactions with Relativistic Radioactive Beams) at FAIR (Facility for Antiproton and Ion Research) is a versatile setup dedicated to the study of reactions induced by high-energy radioactive beams. It will provide kinematically complete measurements with high efficiency, acceptance and resolution, making possible a broad physics program with rare-isotopes. CALIFA (CALorimeter for In-Flight detection of gamma-rays and high energy charged pArticles), is a complex detector based on scintillation crystals, that will surround the target of the R3B experiment. CALIFA will act as a total absorption gamma-calorimeter and spectrometer, as well as identifier of charged particles from target residues. This versatility is its most challenging requirement, demanding a huge dynamic range, to cover from low energy gamma-rays up to 300 MeV protons. This fact, along with the high-energy of the beams determine the conceptual design of the detector, presented in this paper, together with the technical solutions proposed for its construction.
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19.
  • Cortina-Gil, D., et al. (author)
  • CALIFA, a Dedicated Calorimeter for the (RB)-B-3/FAIR
  • 2014
  • In: Nuclear Data Sheets. - : Elsevier BV. - 0090-3752. ; 120, s. 99-101
  • Journal article (peer-reviewed)abstract
    • The (RB)-B-3 experiment (Reactions with Relativistic Radioactive Beams) at FAIR (Facility for Antiproton and Ion Research) is a versatile setup dedicated to the study of reactions induced by high-energy radioactive beams. It will provide kinematically complete measurements with high efficiency, acceptance and resolution, making possible a broad physics program with rare-isotopes. CALIFA (CALorimeter for In-Flight detection of gamma-rays and high energy charged pArticles), is a complex detector based on scintillation crystals, that will surround the target of the (RB)-B-3 experiment. CALIFA will act as a total absorption gamma-calorimeter and spectrometer, as well as identifier of charged particles from target residues. This versatility is its most challenging requirement, demanding a huge dynamic range, to cover from low energy gamma-rays up to 300 MeV protons. This fact, along with the high-energy of the beams determine the conceptual design of the detector, presented in this paper, together with the technical solutions proposed for its construction.
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20.
  • Dorschel, Boris, et al. (author)
  • The International Bathymetric Chart of the Southern Ocean Version 2
  • 2022
  • In: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 9:1
  • Journal article (peer-reviewed)abstract
    • The Southern Ocean surrounding Antarctica is a region that is key to a range of climatic and oceanographic processes with worldwide effects, and is characterised by high biological productivity and biodiversity. Since 2013, the International Bathymetric Chart of the Southern Ocean (IBCSO) has represented the most comprehensive compilation of bathymetry for the Southern Ocean south of 60 degrees S. Recently, the IBCSO Project has combined its efforts with the Nippon Foundation - GEBCO Seabed 2030 Project supporting the goal of mapping the world's oceans by 2030. New datasets initiated a second version of IBCSO (IBCSO v2). This version extends to 50 degrees S (covering approximately 2.4 times the area of seafloor of the previous version) including the gateways of the Antarctic Circumpolar Current and the Antarctic circumpolar frontal systems. Due to increased (multibeam) data coverage, IBCSO v2 significantly improves the overall representation of the Southern Ocean seafloor and resolves many submarine landforms in more detail. This makes IBCSO v2 the most authoritative seafloor map of the area south of 50 degrees S.
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21.
  • Envall, Ida, et al. (author)
  • What is the effect of giving the grazers access to additional nutrient sources on biodiversity in semi-natural pastures? A systematic review protocol
  • 2021
  • In: Environmental Evidence. - : Springer Science and Business Media LLC. - 2047-2382. ; 10:1
  • Research review (peer-reviewed)abstract
    • Background: Semi-natural pastures are unfertilized grasslands with a long history of traditional low-input grazing management. This kind of pastures are recognized for their high species richness. However, as a consequence of modernization of agriculture, many of the semi-natural pastures have been lost during the last century, leading to a serious threat to farmland biodiversity. Semi-natural pastures are relatively low in productivity. Hence, to increase profitability, farmers may want to give the grazing animals access to additional nutrient sources. This can be done either as supplementary feeding, or by fencing the semi-natural pastures into the same enclosure as improved, more nutrient-rich, pastures. These practices are, however, controversial. It is argued that since semi-natural pastures are species-rich partly because they are nutrient-poor, introducing additional nutrients into the system should be avoided. Accordingly, in Sweden, these interventions are often prohibited while receiving financial subsidies for management of semi-natural pastures. However, since many farmers are dependent on such support to maintain their pastures, these prohibitions often cause problems. The question has been raised whether giving the grazers access to additional nutrient sources really affect the biodiversity in semi-natural pastures, as is assumed. The primary aim of the proposed systematic review is to answer this question.Method: Peer-reviewed and grey literature will be searched for using bibliographic databases, search engines, specialist websites and stakeholder contacts. The references will be screened for relevance according to a predefined set of eligibility criteria. The criteria will be tested and clarified iteratively, until consistency in interpretations is achieved. Thereafter, the literature will be screened in two stages, first based upon title and abstract and then by examining full texts. Full text screening will be performed with blinded decisions by two independent reviewers. Each relevant study will then be critically appraised, based on a set of predefined validity criteria. A narrative synthesis will be provided, outlining the evidence base in terms of bibliographic information and study metadata. If possible, quantitative syntheses based on meta-analyses will be performed. Identified relevant knowledge gaps will be highlighted and discussed.
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22.
  • Frisk, U., et al. (author)
  • The Odin satellite - I. Radiometer design and test
  • 2003
  • In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 402:3, s. L27-L34
  • Journal article (peer-reviewed)abstract
    • The Sub-millimetre and Millimetre Radiometer (SMR) is the main instrument on the Swedish, Canadian, Finnish and French spacecraft Odin. It consists of a 1.1 metre diameter telescope with four tuneable heterodyne receivers covering the ranges 486-504 GHz and 541-581 GHz, and one fixed at 118.75 GHz together with backends that provide spectral resolution from 150 kHz to 1 MHz. This Letter describes the Odin radiometer, its operation and performance with the data processing and calibration described in Paper II.
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23.
  • Gnann, T., et al. (author)
  • Fast charging infrastructure for electric vehicles: Today's situation and future needs
  • 2018
  • In: Transportation Research Part D: Transport and Environment. - : Elsevier BV. - 1361-9209. ; 62, s. 314-329
  • Journal article (peer-reviewed)abstract
    • Potential users of plug-in electric vehicles often ask for public charging facilities before buying vehicles . Furthermore, the speed of public charging is often expected to be similar to conventional refueling. For this reason, research on and political interest in public charging focus more and more on fast charging options with higher power rates, yet estimates for future needs are rare. This paper tries to fill this gap by analyzing current charging behavior from a large charging data set from Sweden and Norway and take the findings to calibrate a queuing model for future fast charging infrastructure needs. We find that the ratio of battery electric vehicles to public fast charging points can be similar to other alternative fuels in the future (close to one fast charging point per 1000 vehicles for high power rates of 150 kW). In addition, the surplus on the electricity prices for payoff is only 0.05–0.15 €/kWh per charging point. However, charging infrastructure needs highly depend on battery sizes and power rates that are both likely to increase in the future.
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24.
  • Herbertsson, Lina, et al. (author)
  • Bees increase seed set of wild plants while the proportion of arable land has a variable effect on pollination in European agricultural landscapes
  • 2021
  • In: Plant Ecology and Evolution. - : Societe Royale de Botanique de Belgique. - 2032-3913 .- 2032-3921. ; 154:3, s. 341-350
  • Journal article (peer-reviewed)abstract
    • Background and aims: Agricultural intensification and loss of farmland heterogeneity have contributed to population declines of wild bees and other pollinators, which may have caused subsequent declines in insect-pollinated wild plants.Material and methods: Using data from 37 studies on 22 pollinator-dependent wild plant species across Europe, we investigated whether flower visitation and seed set of insect-pollinated plants decline with an increasing proportion of arable land within 1 km.Key results: Seed set increased with increasing flower visitation by bees, most of which were wild bees, but not with increasing flower visitation by other insects. Increasing proportion of arable land had a strongly variable effect on seed set and flower visitation by bees across studies.Conclusion:Factors such as landscape configuration, local habitat quality, and temporally changing resource availability (e.g. due to mass-flowering crops or honey bee hives) could have modified the effect of arable land on pollination. While our results highlight that the persistence of wild bees is crucial to maintain plant diversity, we also show that pollen limitation due to declining bee populations in homogenized agricultural landscapes is not a universal driver causing parallel losses of bees and insect-pollinated plants. 
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25.
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26.
  • Jakobsson, Kristofer, et al. (author)
  • Bottom-up modeling of oil production : A review of approaches
  • 2014
  • In: Energy Policy. - : Elsevier BV. - 0301-4215 .- 1873-6777. ; 64, s. 113-123
  • Research review (peer-reviewed)abstract
    • Bottom-up models of oil production are continuously being used to guide investments and policymaking. Compared to simpler top-down models, bottom-up models have a number of advantages due to their modularity, flexibility and concreteness. The purposes of this paper is to identify the crucial modeling challenges, compare the different ways in which nine existing models handle them, assess the appropriateness of these models, and point to possibilities of further development. The conclusions are that the high level of detail in bottom-up models is of questionable value for predictive accuracy, but of great value for identifying areas of uncertainty and new research questions. There is a potential for improved qualitative insights through systematic sensitivity analysis. This potential is at present largely unrealized.
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27.
  • Jakobsson, Kristofer, et al. (author)
  • Oil exploration and perceptions of scarcity : The fallacy of early success
  • 2012
  • In: Energy Economics. - : Elsevier BV. - 0140-9883 .- 1873-6181. ; 34:4, s. 1226-1233
  • Journal article (peer-reviewed)abstract
    • It has been suggested that oil exploration may lead to false perceptions of decreasing scarcity. We perform a simulation of the exploration process using Bayesian updating. The approach enables us to isolate the information effect on the success rate and also to quantify the subjective expectation of the total resource size. The area under exploration consists of a number of regions which may differ in their oil content. Exploration is performed with the goal to maximize the expected success rate. The resulting information about the distribution of oil and the total resource size is assumed public knowledge. A number of scenarios with variations in the dimensions of the area under exploration, the oil distribution and initial beliefs are considered. The results indicate that the information effect on the success rate is significant but brief — it might have a considerable impact on price but is an unlikely mechanism behind a long-term declining price trend. However, the information effect on expectations is gradual and persistent. Since exploration is performed in regions where the expected success rate is the highest, the historical success rate will not be representative of the area as a whole. An explorer will tend to overestimate the total resource size, thereby suggesting an alternative mechanism for false perceptions of decreasing scarcity, a mechanism that could be called the “fallacy of early success”.
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28.
  • Jakobsson, Martin, et al. (author)
  • The International Bathymetric Chart of the Arctic Ocean Version 4.0
  • 2020
  • In: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 7:1
  • Journal article (peer-reviewed)abstract
    • Bathymetry (seafloor depth), is a critical parameter providing the geospatial context for a multitude of marine scientific studies. Since 1997, the International Bathymetric Chart of the Arctic Ocean (IBCAO) has been the authoritative source of bathymetry for the Arctic Ocean. IBCAO has merged its efforts with the Nippon Foundation-GEBCO-Seabed 2030 Project, with the goal of mapping all of the oceans by 2030. Here we present the latest version (IBCAO Ver. 4.0), with more than twice the resolution (200 x 200m versus 500 x 500m) and with individual depth soundings constraining three times more area of the Arctic Ocean (similar to 19.8% versus 6.7%), than the previous IBCAO Ver. 3.0 released in 2012. Modern multibeam bathymetry comprises similar to 14.3% in Ver. 4.0 compared to similar to 5.4% in Ver. 3.0. Thus, the new IBCAO Ver. 4.0 has substantially more seafloor morphological information that offers new insights into a range of submarine features and processes; for example, the improved portrayal of Greenland fjords better serves predictive modelling of the fate of the Greenland Ice Sheet. Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12369314
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29.
  • Jakobsson, Simon, et al. (author)
  • Connectivity and management enables fast recovery of plant diversity in new linear grassland elements
  • 2016
  • In: Journal of Vegetation Science. - : Wiley. - 1100-9233 .- 1654-1103. ; 27:1, s. 19-28
  • Journal article (peer-reviewed)abstract
    • Questions: How does small linear grassland elements (paddy levees and road verges) contribute to plant diversity patterns in sites with modern or traditional management? Which factors determine small-scale plant species richness of small linear grassland elements in a Japanese agricultural landscape?Location: Shiga Prefecture, Japan.Methods: Aerial photos from 1963, 1985, 1995 and 2008 were used to investigate landscape changes and to measure landscape structures within a typical agricultural landscape (25km(2)). Plant diversity was investigated in ten paddy levees and ten road verges in each of four traditional (barely any land cover alterations after 1963) and five modern (almost completely changed after 1985) sites. -diversity (mean number of species per plot) and -diversity (total number of species) for all species, specialist and invasive species, respectively, were analysed in relation to site history types and landscape structures. Plot species richness was analysed in relation to site history type, patch age and width, proximity to forest and litter removal.Results: In total, 204 plant species were found, 55 species unique to traditional sites and 13 unique to modern sites. - and -diversity of paddy levees and road verges was significantly higher in traditional sites. Number of specialist species on paddy levees and number of invasive species in road verges was also higher in traditional sites. Age was the strongest predictor of plot species richness on levees; older levees supported higher species richness than younger ones. Litter removal was the strongest predictor (positive effect) of plot species richness in road verges.Conclusions: These results suggest that the colonization credit of new levees in modern sites is decreasing quite rapidly as species quickly establish, approaching almost the same richness values as in traditional sites. However, long continuity of traditional management is still one of the most important contributors to plant diversity and crucial for many species. But small grassland elements can still be of great significance for preserving and enhancing plant diversity in otherwise depleted landscapes, as long as they are managed and connected throughout the landscape.
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30.
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31.
  • Jakobsson, Simon, et al. (author)
  • Contrasting multi-taxa functional diversity patterns along vegetation structure gradients of woody pastures
  • 2020
  • In: Biodiversity and Conservation. - : Springer Science and Business Media LLC. - 0960-3115 .- 1572-9710. ; 29:13, s. 3551-3572
  • Journal article (peer-reviewed)abstract
    • Woody pastures represent keystone habitats for biodiversity in agricultural landscapes, contributing to increased resource availability, landscape heterogeneity and structural variability. High taxonomic diversity is closely linked to vegetation structure in woody pastures, but examining functional characteristics of species assemblages can shed more light on the ecological mechanisms driving divergent responses to habitat characteristics and help guide good management practices. To this end, we use a multi-taxa approach to investigate how plant, bat and bird taxonomic and functional diversity are affected by pasture tree and shrub density, structural complexity and proximate forest cover in southern Sweden. In particular, we use a trait exclusion approach to estimate the sensitivity of diversity-environment relationships to specific traits. We found little congruence between corresponding diversity metrics across taxa. Bird species richness responded stronger to environmental variables than functional diversity metrics, whereas the functional response to the environment was stronger than the taxonomic response among plants and bats. While increasing tree densities increased the taxonomic diversity of all three taxa, a simultaneous functional response was only evident for plants. Contrasting measures of vegetation structure affected different aspects of functional diversity across taxa, driven by different traits. For plants and birds, traits linked to resource use contributed particularly to the functional response, whereas body mass had stronger influence on bat functional diversity metrics. Multi-taxa functional approaches are essential to understand the effects of woody pasture structural attributes on biodiversity, and ultimately inform management guidelines to preserve the biological values in woody pastures.
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32.
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33.
  • Jakobsson, Simon, et al. (author)
  • Exploring the effects of pasture trees on plant community patterns
  • 2019
  • In: Journal of Vegetation Science. - : Wiley. - 1100-9233 .- 1654-1103. ; 30:5, s. 809-820
  • Journal article (peer-reviewed)abstract
    • QuestionsWe aim to answer three questions: (a) what are the effects of canopy shading of different tree species on seed germination of eight understorey grassland species? (b) how is plant species’ occurrence in understorey communities affected by differences in canopy cover and does that depend on tree species composition? and (c) are there mechanistic links between the effects of trees on species’ germination and their occurrence in the understorey plant community?LocationSemi‐natural wooded pastures in the biosphere reserve Östra Vätterbranterna, southern Sweden.MethodsIn this study, we examined the germination of eight grassland plant species in a seed sowing experiment under natural conditions in the field. Seeds were sown beneath and outside the canopy of two tree species within 48 plots split up by four wooded pasture sites. We combined observed germination responses with a plant community survey to assess the effects of canopy cover in relation to tree species composition on plant community responses. We analysed these data in relation to species’ seed mass and vegetative shade tolerance.ResultsShade‐tolerant species germinated better beneath compared to outside tree canopies, without any clear advantage of large‐seeded over small‐seeded species. As expected, species’ shade tolerance was also positively related to canopy cover within the understorey plant community. Importantly, we found strong tree species‐specific effects of canopy shading on the species’ germination response, but not on their presence within the plant community. However, optimal canopy cover conditions for germination and for the mature plants differed across grassland species and depended on tree species.ConclusionsOur results show that different tree species play key ecosystem engineering roles in shaping wooded grassland plant community composition at the germination stage. Management practices favouring specific tree species may therefore be highly relevant for targeted biodiversity conservation of wooded semi‐natural grasslands.
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34.
  • Jakobsson, Simon, 1987-, et al. (author)
  • Governing nature by numbers - EU subsidy regulations do not capture the unique values of woody pastures
  • 2015
  • In: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 191, s. 1-9
  • Journal article (peer-reviewed)abstract
    • A vast majority of European farmers are dependent on EU subsidies, which makes subsidy regulations through the Common Agricultural Policy (CAP) powerful tools in shaping agricultural landscapes. Unfortunately, steering recommendations are sometimes arbitrary, like in the case of pasture management, where 50 trees per hectare constitute an upper limit to qualify for subsidies. Although pasture biodiversity is well studied and the core of many CAP conservation programmes, it is seldom studied as direct effects of subsidy systems. In this paper, we examine plant diversity in relation to the impact of subsidy systems in Swedish woody pastures along a gradient from 3 to 214 trees per hectare. We selected 64 sites where we recorded vascular plants, soil properties and canopy cover. We found a general increase in γ- and β-diversity along the gradient, whereas α-diversity and the number of grassland specialists remained indifferent along the gradient. Additionally, tree density, organic content and C:N-ratio were the strongest predictors of species composition. Hence, when CAP regulations encourage tree cutting for pastures to qualify for subsidies there is risk of homogenisation of EU grasslands, leading to decreased γ- and β-diversity. If a general target for the subsidies is to increase biodiversity, there is need to scrutinise these regulation details to preserve the high values of woody pastures. We argue that habitat variation, species diversity and low intensity management, rather than a specific number of trees, should be the main incentives for financial support to preserve biodiversity.
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35.
  • Jakobsson, Simon, et al. (author)
  • How does roadside vegetation management affect the diversity of vascular plants and invertebrates? A systematic review
  • 2018
  • In: Environmental Evidence. - : Springer Science and Business Media LLC. - 2047-2382. ; 7:1
  • Research review (peer-reviewed)abstract
    • Background: With appropriate management, based on vegetation removal that reverses late-successional vegetation stages, roadsides can support high levels of biodiversity. However, current recommendations for roadside management to conserve or restore biodiversity are largely based on research on non-roadside grassland habitats, and much of the evidence on how roadside management practices affect biodiversity is found in non-peer-reviewed grey literature. Therefore, based on suggestions from key stakeholders and an initial systematic map that identified 97 studies on how biodiversity is affected by vegetation removal on roadsides, we conducted a full systematic review of the effects on plant and invertebrate diversity of disturbance-based maintenance of roadsides. Methods: The review was restricted to effects of non-chemical interventions such as mowing, burning, grazing and mechanical shrub removal. Studies were selected from the systematic map and from an updated search for more recent literature using a priori eligibility criteria. Relevant articles were subject to critical appraisal of clarity and susceptibility to bias, and studies with low or unclear validity were excluded from the review. Data on species richness, species diversity and abundance of functional groups were extracted together with metadata on site properties and other potential effect modifiers. Results from the 54 included studies were summarised in a narrative synthesis, and impacts of mowing practices on the total species richness and diversity of plants and on the abundance of forbs, graminoids and woody plants were quantitatively analysed using t tests of study-level effect ratios. Results: Nearly all of the 54 studies included in the review were conducted in Europe (29) or North America (24). The vast majority of studies (48) examined impacts of mowing. Effects on vascular plants were reported in 51 studies, whereas 8 of the studies reported on invertebrates. Quantitative analysis of plant species richness and species diversity showed that mowing effects were dependent on the interplay between mowing frequency and hay removal. Thus, there were no statistically significant overall effects of mowing vs. no mowing, frequency of mowing, timing of mowing or hay removal. However, species richness was higher in roadsides mowed once or twice per year with hay removal than in unmown roadsides, and positively affected by mowing twice compared to once per year. Similar, but less pronounced, effects were found for plant species diversity. In addition, mowing had a negative impact on woody plant abundance, and increased mowing frequency had a negative impact on graminoid abundance. The few studies on invertebrates showed effects that diverged across taxon groups, and there was not enough data for quantitative analysis of these results. Conclusions: The results provide evidence on the effects of mowing on plant species richness. To increase plant species richness, roadsides should be mowed each year, preferably twice per year, and hay should be removed after each cutting. The review also identifies large knowledge gaps concerning roadside management and its effects on biodiversity, especially regarding invertebrates. Hence, this systematic review provides not only a valuable basis for evidence-based management but also guidance for future research on this topic, essential to inform management of road networks for biodiversity conservation.
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36.
  • Jakobsson, Simon, et al. (author)
  • The importance of trees for woody pasture bird diversity and effects of the European Union's tree density policy
  • 2017
  • In: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 54:6, s. 1638-1647
  • Journal article (peer-reviewed)abstract
    • 1. Recent reforms in the Common Agricultural Policy aim for a greening of the subsidy system with potential improvements for biodiversity conservation. As part of that process, the tree density limit for pastures to qualify for European Union subsidies has been increased from 50 to 100 trees per hectare. However, recent studies show that the high biodiversity values of these habitats may be threatened by these limits, highlighting the need for policy improvements. Still, little is known about the direct effects of tree density limitations on bird communities in woody pastures. 2. We investigated how bird diversity and species composition are affected by tree density in 49 Swedish woody pastures along a gradient of 4-214 trees per hectare. We recorded bird communities, tree density and stand structure estimates in the field and estimated forest cover in the surrounding landscape from aerial photos. Using generalised additive models and redundancy analysis, we analysed how bird territorial species richness, bird abundance and species composition are affected by tree density, taking into account other local and landscape scale explanatory variables. 3. Tree density had a significant positive effect on bird species richness at low tree densities and species richness saturated at approximately 50 trees per hectare. Shrub density had a significant positive linear effect on both bird species richness and abundance. Tree and shrub density were also the major drivers of bird community composition, with secondary effects of tree species diversity and landscape forest cover. 4. Policy implications. Our results show that tree density is not the limiting factor, but rather a driver of bird diversity and species composition in woody pastures and that tree density limits may fail to capture the whole range of biological values. To improve policy recommendations, we therefore stress the importance of considering additional social-ecological drivers associated to management quality, e.g. taking into account moral and cultural motivations among farmers, to preserve biodiversity in woody pastures.
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37.
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38.
  • Jakobsson, Simon, 1987- (author)
  • Wooded or treeless pastures? : Linking policy, farmers' decisions and biodiversity
  • 2018
  • Doctoral thesis (other academic/artistic)abstract
    • Worldwide, biodiversity conservation is one of the key challenges for a sustainable future of nature and society. It is particularly important to preserve high quality habitats within otherwise intensively managed agricultural landscapes. Within the European Union (EU), farmers are highly dependent on agricultural subsidies through the Common Agricultural Policy (CAP), which hence have a strong influence on management and biodiversity. In European agricultural landscapes, wooded pastures form important habitats that contribute to landscape level heterogeneity and high local biodiversity, values which are often closely linked to trees. Unfortunately, many of these values were put at risk when a tree density limitation was introduced within the CAP, encouraging farmers to keep pastures open and ensuring grazing management. However, limiting tree density to a specific number to increase biodiversity finds little basis in the scientific literature. The main objective of this thesis is therefore to investigate how different measures of biodiversity across multiple taxa are affected by tree density and to study the farmers' perspective on this CAP regulation. Wooded pastures in the biosphere reserve Östra Vätterbranterna in southern Sweden were used as study sites. This thesis shows that encouraging farmers to cut trees to receive subsidies weakens the link between social and ecological values of wooded pastures, with potential subsequent losses in biodiversity. Trees were almost exclusively positive for biodiversity within this study system, increasing the species richness of plants, birds and bats. However, functional diversity across these taxa were mainly affected by other vegetation attributes within and around the pastures, such as shrub density and surrounding forest cover. A seed sowing experiment showed how trees partly shape plant communities already at the germination stage. Further, responses of functional diversity was mainly driven by resource use related traits among plants and birds, whereas bat functional diversity responses were mainly determined by their ability to manoeuvre through the micro-habitats of wooded pastures. Based on this thesis, I conclude that the tree density limit proposed by the EU has failed to capture the unique biological values of continuously managed wooded pastures and that the social-ecological links between policy, management and biodiversity are threatened by number specific governance of nature. It is therefore promising that the EU in November 2017 announced to open up for excluding the tree density focus in the CAP. Further development of the CAP can benefit from the findings of this thesis, revealing important knowledge gaps on biodiversity patterns in relation to trees in pastures.
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39.
  • Jakobsson, Simon, 1987- (author)
  • Woody or treeless pastures? Effects of EU tree density limitations on biodiversity in woody pastures
  • 2015
  • Licentiate thesis (other academic/artistic)abstract
    • The high biological and cultural values of traditionally managed rural landscapes are threatened by habitat change and degradation due to homogenisation through modern agricultural practices and abandonment. Woody pastures are important for many different taxa, and hence crucial for biodiversity conservation in these agricultural landscapes. To mitigate biodiversity loss, agricultural policy recommendations and subsidies are important tools, but if not implemented properly they may have the opposite effect. To keep agricultural landscapes open and to preserve biodiversity, the Common Agricultural Policy (CAP) of the European Union (EU) regulates how many trees farmers are allowed to have on their pastures to receive subsidies from the EU. A seemingly arbitrary limit was set to 50 trees/ha in 2003, which changed recently to 100 trees/ha. However, woody pastures are environments where high nature values often arise from the trees themselves, whereas there is little evidence on how biodiversity is directly affected by tree density in woody pastures. In this study, the tree density limit is targeted to investigate the effects on plant and bird diversity in 64 Swedish woody pastures along a gradient from 0 to 200 trees/ha. The results show that tree density is one of the major drivers of plant diversity, by favouring shade tolerant species without having a negative effect on less shade tolerant grassland specialists. Tree density positively affect bird diversity, an effect saturating at medium dense pastures but large species turnover rates along the gradient point at a variety of species found within woody pastures. Woody pastures with high tree densities in this study contribute substantially to biodiversity as heterogeneous environment enables high species richness. This thesis demonstrates a mismatch between subsidy systems and biological values that need to be further scrutinised to preserve biodiversity of agricultural landscapes.
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40.
  • Jennings, Anne, et al. (author)
  • Modern and early Holocene ice shelf sediment facies from Petermann Fjord and northern Nares Strait, northwest Greenland
  • 2022
  • In: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 283
  • Journal article (peer-reviewed)abstract
    • Based on sediment cores and geophysical data collected from Petermann Fjord and northern Nares Strait, NW Greenland, an Arctic ice shelf sediment facies is presented that distinguishes sub and pro ice shelf environments. Sediment cores were collected from sites beneath the present day Petermann Ice Tongue (PIT) and in deglacial sediments of northern Nares Strait with a focus on understanding the glacial and oceanographic history over the last 11,000 cal yr BP. The modern sub ice shelf sediment facies in Petermann Fjord is laminated and devoid of coarse clasts (IRD) due to strong basal melting that releases debris (debris filtering) from the basal ice at the grounding zone driven by buoyant subglacial meltwater and entrained Atlantic Water. Laminated sediments in the deep basin proximal to the gounding zone comprise layers of fine mud formed by suspension settling from turbid meltwater plumes (plumites) interrupted by normally graded very fine sand to medium silt layers with sharp basal contacts and rip-up clasts of mud, interpreted as turbidites. An inner fjord sill limits distribution of sediment gravity flows from the grounding zone to the deep inner fjord basin, such that sites on the inner sill and beyond the ice tongue largely only comprise plumites. Bioturbation and foraminiferal abundances increase with distance from the grounding zone. The benthic foraminiferal species, Elphidium clavatum is absent beneath the ice tongue, but dominant in the turbid meltwater influenced environment beyond the ice tongue. The very sparse IRD in sediments beneath the PIT and in the fjord beyond the PIT derives mainly from englacial debris in the ice tongue, side valley glaciers, rock falls from the steep fjord walls and sea ice.We use the modern ice shelf sediment facies characteristics to infer the past presence of ice shelves in northern Nares Strait using analyses of sediment cores from several cruises (OD1507, HLY03, 2001LSSL, RYDER19). On bathymetric highs, bioturbated mud with dispersed IRD overlies a 10–15 m thick, distinctly laminated silt and clay unit with rare coarse clasts and sparse foraminifera which forms a sediment drape of nearly uniform thickness. We interpret these laminated sediments to represent glaciomarine deposition by meltwater plumes emanating from ice streams that terminated in floating ice shelves. IRD layers, shifts in sediment composition (qXRD, MS and XRF) and faunal assemblage changes in the laminated unit document periods of ice-shelf instability sometimes, but not always, coupled with grounding zone retreat. Our deglacial reconstruction, including ice shelves, begins ∼10.7 cal ka BP, with confluent ice streams grounded in Hall Basin fronted by the Robeson Channel ice shelf. Ice shelf breakup and grounding zone retreat to relatively stable grounding zones at Kennedy Channel and the mouth of Petermann Fjord was accomplished by 9.4 cal ka BP when the Hall Basin ice shelf was established. This ice shelf broke up and reformed once prior to the final break up at 8.5 to 8.4 cal ka BP marking ice stream collapse, separation of Greenland and Innuitian ice sheets, and the opening of Nares Strait for Arctic-Atlantic throughflow. The Petermann ice shelf remained in Hall Basin until the Petermann Glacier retreated from the fjord mouth ∼7.1 cal ka BP. The resilience of these northern ice streams to strong early Holocene insolation and subsurface Atlantic Water advection is attributed to their northern aspect, buttressing by narrow passages, and high ice flux from the Greenland Ice Sheet (GIS).
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41.
  • Kutsche, Lisa K., et al. (author)
  • Combined Experimental and System-Level Analyses Reveal the Complex Regulatory Network of miR-124 during Human Neurogenesis
  • 2018
  • In: Cell systems. - : Elsevier BV. - 2405-4712. ; 7:4, s. 438-452
  • Journal article (peer-reviewed)abstract
    • Non-coding RNAs regulate many biological processes including neurogenesis. The brain-enriched miR-124 has been assigned as a key player of neuronal differentiation via its complex but little understood regulation of thousands of annotated targets. To systematically chart its regulatory functions, we used CRISPR/Cas9 gene editing to disrupt all six miR-124 alleles in human induced pluripotent stem cells. Upon neuronal induction, miR-124-deleted cells underwent neurogenesis and became functional neurons, albeit with altered morphology and neurotransmitter specification. Using RNA-induced-silencing-complex precipitation, we identified 98 high-confidence miR-124 targets, of which some directly led to decreased viability. By performing advanced transcription-factor-network analysis, we identified indirect miR-124 effects on apoptosis, neuronal subtype differentiation, and the regulation of previously uncharacterized zinc finger transcription factors. Our data emphasize the need for combined experimental- and system-level analyses to comprehensively disentangle and reveal miRNA functions, including their involvement in the neurogenesis of diverse neuronal cell types found in the human brain.
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42.
  • Larena, Maximilian, et al. (author)
  • Multiple migrations to the Philippines during the last 50,000 years
  • 2021
  • In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences (PNAS). - 0027-8424 .- 1091-6490. ; 118:13
  • Journal article (peer-reviewed)abstract
    • Island Southeast Asia has recently produced several surprises regarding human history, but the region's complex demography remains poorly understood. Here, we report similar to 2.3 million genotypes from 1,028 individuals representing 115 indigenous Philippine populations and genome-sequence data from two similar to 8,000-y-old individuals from Liangdao in the Taiwan Strait. We show that the Philippine islands were populated by at least five waves of human migration: initially by Northern and Southern Negritos (distantly related to Australian and Papuan groups), followed by Manobo, Sama, Papuan, and Cordilleran-related populations. The ancestors of Cordillerans diverged from indigenous peoples of Taiwan at least similar to 8,000 y ago, prior to the arrival of paddy field rice agriculture in the Philippines similar to 2,500 y ago, where some of their descendants remain to be the least admixed East Asian groups carrying an ancestry shared by all Austronesian-speaking populations. These observations contradict an exclusive "out-of-Taiwan" model of farming-language-people dispersal within the last four millennia for the Philippines and Island Southeast Asia. Sama-related ethnic groups of southwestern Philippines additionally experienced some minimal South Asian gene flow starting similar to 1,000 y ago. Lastly, only a few lowlanders, accounting for <1% of all individuals, presented a low level of West Eurasian admixture, indicating a limited genetic legacy of Spanish colonization in the Philippines. Altogether, our findings reveal a multilayered history of the Philippines, which served as a crucial gateway for the movement of people that ultimately changed the genetic landscape of the Asia-Pacific region.
  •  
43.
  • Larena, Maximilian, et al. (author)
  • Philippine Ayta possess the highest level of Denisovan ancestry in the world
  • 2021
  • In: Current Biology. - : Cell Press. - 0960-9822 .- 1879-0445. ; 31:19, s. 4219-4230
  • Journal article (peer-reviewed)abstract
    • Multiple lines of evidence show that modern humans interbred with archaic Denisovans. Here, we report an account of shared demographic history between Australasians and Denisovans distinctively in Island Southeast Asia. Our analyses are based on-2.3 million genotypes from 118 ethnic groups of the Philippines, including 25 diverse self-identified Negrito populations, along with high-coverage genomes of Australopapuans and Ayta Magbukon Negritos. We show that Ayta Magbukon possess the highest level of Denisovan ancestry in the world--30%-40% greater than that of Australians and Papuans-consistent with an independent admixture event into Negritos from Denisovans. Together with the recently described Homo luzonensis, we suggest that there were multiple archaic species that inhabited the Philippines prior to the arrival of modern humans and that these archaic groups may have been genetically related. Altogether, our findings unveil a complex intertwined history of modern and archaic humans in the Asia-Pacific region, where distinct Islander Denisovan populations differentially admixed with incoming Australasians across multiple locations and at various points in time.
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44.
  • Laura Aaltonen, H., et al. (author)
  • Airspace Dimension Assessment with nanoparticles reflects lung density as quantified by MRI
  • 2018
  • In: International Journal of Nanomedicine. - 1176-9114 .- 1178-2013. ; 13, s. 2989-2995
  • Journal article (peer-reviewed)abstract
    • Background: Airspace Dimension Assessment with inhaled nanoparticles is a novel method to determine distal airway morphology. This is the first empirical study using Airspace Dimension Assessment with nanoparticles (AiDA) to estimate distal airspace radius. The technology is relatively simple and potentially accessible in clinical outpatient settings. Method: Nineteen never-smoking volunteers performed nanoparticle inhalation tests at multiple breath-hold times, and the difference in nanoparticle concentration of inhaled and exhaled gas was measured. An exponential decay curve was fitted to the concentration of recovered nanoparticles, and airspace dimensions were assessed from the half-life of the decay. Pulmonary tissue density was measured using magnetic resonance imaging (MRI). Results: The distal airspace radius measured by AiDA correlated with lung tissue density as measured by MRI (ρ = -0.584; p = 0.0086). The linear intercept of the logarithm of the exponential decay curve correlated with forced expiratory volume in one second (FEV1) (ρ = 0.549; p = 0.0149). Conclusion: The AiDA method shows potential to be developed into a tool to assess conditions involving changes in distal airways, eg, emphysema. The intercept may reflect airway properties; this finding should be further investigated.
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45.
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46.
  • Mätlik, Kärt, et al. (author)
  • Elevated endogenous GDNF induces altered dopamine signalling in mice and correlates with clinical severity in schizophrenia.
  • 2022
  • In: Molecular Psychiatry. - : Springer Nature. - 1359-4184 .- 1476-5578.
  • Journal article (peer-reviewed)abstract
    • Presynaptic increase in striatal dopamine is the primary dopaminergic abnormality in schizophrenia, but the underlying mechanisms are not understood. Here, we hypothesized that increased expression of endogenous GDNF could induce dopaminergic abnormalities that resemble those seen in schizophrenia. To test the impact of GDNF elevation, without inducing adverse effects caused by ectopic overexpression, we developed a novel in vivo approach to conditionally increase endogenous GDNF expression. We found that a 2-3-fold increase in endogenous GDNF in the brain was sufficient to induce molecular, cellular, and functional changes in dopamine signalling in the striatum and prefrontal cortex, including increased striatal presynaptic dopamine levels and reduction of dopamine in prefrontal cortex. Mechanistically, we identified adenosine A2a receptor (A2AR), a G-protein coupled receptor that modulates dopaminergic signalling, as a possible mediator of GDNF-driven dopaminergic abnormalities. We further showed that pharmacological inhibition of A2AR with istradefylline partially normalised striatal GDNF and striatal and cortical dopamine levels in mice. Lastly, we found that GDNF levels are increased in the cerebrospinal fluid of first episode psychosis patients, and in post-mortem striatum of schizophrenia patients. Our results reveal a possible contributor for increased striatal dopamine signalling in a subgroup of schizophrenia patients and suggest that GDNF-A2AR crosstalk may regulate dopamine function in a therapeutically targetable manner.
  •  
47.
  • Raghavan, Maanasa, et al. (author)
  • Genomic evidence for the Pleistocene and recent population history of Native Americans
  • 2015
  • In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 349:6250
  • Journal article (peer-reviewed)abstract
    • Howand when the Americas were populated remains contentious. Using ancient and modern genome-wide data, we found that the ancestors of all present-day Native Americans, including Athabascans and Amerindians, entered the Americas as a single migration wave from Siberia no earlier than 23 thousand years ago (ka) and after no more than an 8000-year isolation period in Beringia. After their arrival to the Americas, ancestral Native Americans diversified into two basal genetic branches around 13 ka, one that is now dispersed across North and South America and the other restricted to North America. Subsequent gene flow resulted in some Native Americans sharing ancestry with present-day East Asians (including Siberians) and, more distantly, Australo-Melanesians. Putative "Paleoamerican" relict populations, including the historical Mexican Pericues and South American Fuego-Patagonians, are not directly related to modern Australo-Melanesians as suggested by the Paleoamerican Model.
  •  
48.
  • Raghavan, Maanasa, et al. (author)
  • Upper Palaeolithic Siberian genome reveals dual ancestry of Native Americans
  • 2014
  • In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 505:7481, s. 87-
  • Journal article (peer-reviewed)abstract
    • The origins of the First Americans remain contentious. Although Native Americans seem to be genetically most closely related to east Asians(1-3), there is no consensus with regard to which specific Old World populations they are closest to(4-8). Here we sequence the draft genome of an approximately 24,000-year-old individual (MA-1), from Mal'ta in south-central Siberia(9), to an average depth of 1x. To our knowledge this is the oldest anatomically modern human genome reported to date. The MA-1 mitochondrial genome belongs to haplogroup U, which has also been found at high frequency among Upper Palaeolithic and Mesolithic European hunter-gatherers(10-12), and the Y chromosome of MA-1 is basal to modern-day western Eurasians and near the root of most Native American lineages(5). Similarly, we find autosomal evidence that MA-1 is basal to modern-day western Eurasians and genetically closely related to modern-day Native Americans, with no close affinity to east Asians. This suggests that populations related to contemporary western Eurasians had a more north-easterly distribution 24,000 years ago than commonly thought. Furthermore, we estimate that 14 to 38% of Native American ancestry may originate through gene flow from this ancient population. This is likely to have occurred after the divergence of Native American ancestors from east Asian ancestors, but before the diversification of Native American populations in the New World. Gene flow from the MA-1 lineage into Native American ancestors could explain why several crania from the First Americans have been reported as bearing morphological characteristics that do not resemble those of east Asians(2,13). Sequencing of another south-central Siberian, Afontova Gora-2 dating to approximately 17,000 years ago(14), revealed similar autosomal genetic signatures as MA-1, suggesting that the region was continuously occupied by humans throughout the Last Glacial Maximum. Our findings reveal that western Eurasian genetic signatures in modern-day Native Americans derive not only from post-Columbian admixture, as commonly thought, but also from a mixed ancestry of the First Americans.
  •  
49.
  • Rasmussen, Morten, et al. (author)
  • The genome of a Late Pleistocene human from a Clovis burial site in western Montana
  • 2014
  • In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 506:7487, s. 225-229
  • Journal article (peer-reviewed)abstract
    • Clovis, with its distinctive biface, blade and osseous technologies, is the oldest widespread archaeological complex defined in North America, dating from 11,100 to 10,700 C-14 years before present (BP) (13,000 to 12,600 calendar years BP)(1,2). Nearly 50 years of archaeological research point to the Clovis complex as having developed south of the North American ice sheets from an ancestral technology(3). However, both the origins and the genetic legacy of the people who manufactured Clovis tools remain under debate. It is generally believed that these people ultimately derived from Asia and were directly related to contemporary Native Americans(2). An alternative, Solutrean, hypothesis posits that the Clovis predecessors emigrated from southwestern Europe during the Last Glacial Maximum(4). Here we report the genome sequence of a male infant (Anzick-1) recovered from the Anzick burial site in western Montana. The human bones date to 10,705 +/- 35 C-14 years BP (approximately 12,707-12,556 calendar years BP) and were directly associated with Clovis tools. We sequenced the genome to an average depth of 14.4x and show that the gene flow from the Siberian Upper Palaeolithic Mal'ta population(5) into Native American ancestors is also shared by the Anzick-1 individual and thus happened before 12,600 years BP. We also show that the Anzick-1 individual is more closely related to all indigenous American populations than to any other group. Our data are compatible with the hypothesis that Anzick-1 belonged to a population directly ancestral to many contemporary Native Americans. Finally, we find evidence of a deep divergence in Native American populations that predates the Anzick-1 individual.
  •  
50.
  • Roellig, Marlene, et al. (author)
  • Post Hoc Assessment of Stand Structure Across European Wood-Pastures : Implications for Land Use Policy
  • 2018
  • In: Rangeland Ecology & Management. - : Elsevier BV. - 1550-7424 .- 1551-5028. ; 71:5, s. 526-535
  • Journal article (peer-reviewed)abstract
    • Europe's woodland and savanna rangelands, often part of silvopastoral systems known as wood-pastures, are deteriorating because of abandonment that leads to return to a forested state or lack of tree regeneration from overgrazing or tree and shrub removal. Despite numerous local studies, there has been no broader survey of the stand structure of European wood-pastures showing which systems are at risk of losing their semiopen character. This overview aims to 1) show some of the differences and similarities in wood-pastures from landscapes across Europe and 2) identify which of these wood-pastures are at risk of losing their semiopen character. We collated a dataset of 13 693 trees from 390 plots in wood-pastures from eight different European regions (western Estonia, eastern Greece, northern Germany, Hungary, northern Italy, southern Portugal, central Romania, and southern Sweden), including tree diameters at breast height, tree density, management type, and tree species composition. On the basis of their structural characteristics, we classified wood-pastures using principal component analysis (PCA) and cluster analysis. The PCA showed a gradient from dense wood-pastures with high levels of regeneration (e.g., in Estonia) to sparse wood-pastures with large trees but a lack of regeneration (e.g., in Romania). Along this gradient, we identified three main groups of wood-pastures: 1) sparse wood-pastures with mostly big trees; 2) dense wood-pastures composed of small trees, and 3) wood-pastures containing a wide range of tree ages. Our results show a large structural gradient in European wood-pastures, as well as regeneration problems varying in their severity, highlighting the importance of social-ecological context for wood-pasture conditions. To maintain the ecological and cultural integrity of European wood-pastures, we suggest 1) more comprehensively considering them in European policies such as the Common Agricultural Policy and EU Habitats Directive, while 2) taking into account their structural characteristics and social-ecological backgrounds.
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