| 1. |
- Abelev, B., et al.
(författare)
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J/psi production as a function of charged particle multiplicity in pp collisions at root s=7 TeV
- 2012
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Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 712:3, s. 165-175
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Tidskriftsartikel (refereegranskat)abstract
- The ALICE Collaboration reports the measurement of the relative J/psi yield as a function of charged particle pseudorapidity density dN(ch)/d eta in pp collisions at root s = 7 TeV at the LHC. J/psi particles are detected for p(t) > 0, in the rapidity interval vertical bar y vertical bar < 0.9 via decay into e(+)e(-), and in the interval 2.5 < y < 4.0 via decay into mu(+)/mu(-) pairs. An approximately linear increase of the J/psi yields normalized to their event average (dN(J/psi)/dy)/(dN(J/psi)/dy) with (dN(ch)/c eta)/(dN(ch)/d eta) is observed in both rapidity ranges, where dN(ch)/d eta is measured within vertical bar eta vertical bar < 1 and p(t) > 0. In the highest multiplicity interval with (dN(ch)/d eta)(bin)) = 24.1, corresponding to four times the minimum bias multiplicity density, an enhancement relative to the minimum bias J/psi yield by a factor of about 5 at 2.5 < y <4 (8 at vertical bar y vertical bar < 0.9) is observed. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved.
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| 2. |
- Abele, H., et al.
(författare)
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Particle physics at the European Spallation Source
- 2023
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Ingår i: Physics reports. - : Elsevier. - 0370-1573 .- 1873-6270. ; 1023, s. 1-84
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Forskningsöversikt (refereegranskat)abstract
- Presently under construction in Lund, Sweden, the European Spallation Source (ESS) will be the world’s brightest neutron source. As such, it has the potential for a particle physics program with a unique reach and which is complementary to that available at other facilities. This paper describes proposed particle physics activities for the ESS. These encompass the exploitation of both the neutrons and neutrinos produced at the ESS for high precision (sensitivity) measurements (searches).
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| 3. |
- Oskarsson, Mattias C. R., et al.
(författare)
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Mitochondrial DNA data indicate an introduction through Mainland Southeast Asia for Australian dingoes and Polynesian domestic dogs
- 2012
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Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 279:1730, s. 967-974
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Tidskriftsartikel (refereegranskat)abstract
- In the late stages of the global dispersal of dogs, dingoes appear in the Australian archaeological record 3500 years BP, and dogs were one of three domesticates brought with the colonization of Polynesia, but the introduction routes to this region remain unknown. This also relates to questions about human history, such as to what extent the Polynesian culture was introduced with the Austronesian expansion from Taiwan or adopted en route, and whether pre-Neolithic Australia was culturally influenced by the surrounding Neolithic world. We investigate these questions by mapping the distribution of the mtDNA founder haplotypes for dingoes (A29) and ancient Polynesian dogs (Arc1 and Arc2) in samples across Southern East Asia (n = 424) and Island Southeast Asia (n = 219). All three haplotypes were found in South China, Mainland Southeast Asia and Indonesia but absent in Taiwan and the Philippines, and the mtDNA diversity among dingoes indicates an introduction to Australia 4600-18 300 years BP. These results suggest that Australian dingoes and Polynesian dogs originate from dogs introduced to Indonesia via Mainland Southeast Asia before the Neolithic, and not from Taiwan together with the Austronesian expansion. This underscores the complex origins of Polynesian culture and the isolation from Neolithic influence of the pre-Neolithic Australian culture.
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| 4. |
- van Asch, Barbara, et al.
(författare)
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Pre-Columbian origins of Native American dog breeds, with only limited replacement by European dogs, confirmed by mtDNA analysis
- 2013
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Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society Publishing. - 0962-8452 .- 1471-2954. ; 280:1766, s. 20131142-
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Tidskriftsartikel (refereegranskat)abstract
- Dogs were present in pre-Columbian America, presumably brought by early human migrants from Asia. Studies of free-ranging village/street dogs have indicated almost total replacement of these original dogs by European dogs, but the extent to which Arctic, North and South American breeds are descendants of the original population remains to be assessed. Using a comprehensive phylogeographic analysis, we traced the origin of the mitochondrial DNA lineages for Inuit, Eskimo and Greenland dogs, Alaskan Malamute, Chihuahua, xoloitzcuintli and perro sin pelo del Peru, by comparing to extensive samples of East Asian (n = 984) and European dogs (n = 639), and previously published pre-Columbian sequences. Evidence for a pre-Columbian origin was found for all these breeds, except Alaskan Malamute for which results were ambigous. No European influence was indicated for the Arctic breeds Inuit, Eskimo and Greenland dog, and North/South American breeds had at most 30% European female lineages, suggesting marginal replacement by European dogs. Genetic continuity through time was shown by the sharing of a unique haplotype between the Mexican breed Chihuahua and ancient Mexican samples. We also analysed free-ranging dogs, confirming limited pre-Columbian ancestry overall, but also identifying pockets of remaining populations with high proportion of indigenous ancestry, and we provide the first DNA-based evidence that the Carolina dog, a free-ranging population in the USA, may have an ancient Asian origin.
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| 5. |
- Ardalan, Arman, et al.
(författare)
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African origin for Madagascan dogs revealed by mtDNA analysis
- 2015
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Ingår i: Royal Society Open Science. - : ROYAL SOCIETY OPEN SCIENCE. - 2054-5703.
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Tidskriftsartikel (refereegranskat)abstract
- Madagascar was one of the last major land masses to be inhabited by humans. It was initially colonized by Austronesian speaking Indonesians 1500–2000 years ago, but subsequent migration from Africa has resulted in approximately equal genetic contributions from Indonesia and Africa, and the material culture has mainly African influences. The dog, along with the pig and the chicken, was part of the Austronesian Neolithic culture, and was furthermore the only domestic animal to accompany humans to every continent in ancient times. To illuminate Madagascan cultural origins and track the initial worldwide dispersal of dogs, we here investigated the ancestry of Madagascan dogs. We analysed mtDNA control region sequences in dogs from Madagascar (n=145) and compared it with that from potential ancestral populations in Island Southeast Asia (n=219) and sub-Saharan Africa (n=493). We found that 90% of the Madagascan dogs carried a haplotype that was also present in sub-Saharan Africa and that the remaining lineages could all be attributed to a likely origin in Africa. By contrast, only 26% of Madagascan dogs shared haplotypes with Indonesian dogs, and one haplotype typical for Austronesian dogs, carried by more than 40% of Indonesian and Polynesian dogs, was absent among the Madagascan dogs. Thus, in contrast to the human population, Madagascan dogs seem to trace their origin entirely from Africa. These results suggest that dogs were not brought to Madagascar by the initial Austronesian speaking colonizers on their transoceanic voyage, but were introduced at a later stage, together with human migration and cultural influence from Africa.
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| 6. |
- Ersmark, Erik, et al.
(författare)
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From the Past to the Present : Wolf Phylogeography and Demographic History Based on the Mitochondrial Control Region
- 2016
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Ingår i: Frontiers in Ecology and Evolution. - : FRONTIERS MEDIA SA. - 2296-701X. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- The global distribution of the gray wolf (Canis lupus) is a complex assembly consisting of a large number of populations and described subspecies. How these lineages are related to one another is still not fully resolved, largely due to the fact that large geographical regions remain poorly sampled both at the core and periphery of the species' range. Analyses of ancient wolves have also suffered from uneven sampling, but have shown indications of a major turnover at some point during the Pleistocene-Holocene boundary in northern North America. Here we analyze variation in the mitochondrial control region in 122 contemporary wolves from some of the less studied populations, as well as six samples from the previously unstudied Greenland subspecies (Canis I. orlon) and two Late Pleistocene samples from Siberia. Together with the publicly available control region sequences of both modern and ancient wolves, this study examines genetic diversity on a wide geographical and temporal scale that includes both Eurasia and North America. We identify 13 new haplotypes, of which the majority is found in northern and eastern Asia. The results show that the Greenland samples are all represented by one haplotype, previously identified in North American wolves, among which this population seems to trace its maternal lineage. The phylogeny and network analyses show a wide spatial distribution of several lineages, but also some clusters with more distinct geographical affiliation. In North America, we find support for an end-Pleistocene population bottleneck through coalescent simulations under an approximate Bayesian framework in contrast to previous studies that suggested an extinction-replacement event. However, we find no support for a similar bottleneck in Eurasia. Overall, this global analysis helps to clarify our understanding of the complex history for wolves in Eurasia and North America.
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| 7. |
- Natanaelsson, Christian, et al.
(författare)
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Dog Y chromosomal DNA sequence : identification, sequencing and SNP discovery
- 2006
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Ingår i: BMC Genetics. - : Springer Science and Business Media LLC. - 1471-2156. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Background: Population genetic studies of dogs have so far mainly been based on analysis of mitochondrial DNA, describing only the history of female dogs. To get a picture of the male history, as well as a second independent marker, there is a need for studies of biallelic Y-chromosome polymorphisms. However, there are no biallelic polymorphisms reported, and only 3200 bp of non-repetitive dog Y-chromosome sequence deposited in GenBank, necessitating the identification of dog Y chromosome sequence and the search for polymorphisms therein. The genome has been only partially sequenced for one male dog, disallowing mapping of the sequence into specific chromosomes. However, by comparing the male genome sequence to the complete female dog genome sequence, candidate Y-chromosome sequence may be identified by exclusion. Results: The male dog genome sequence was analysed by Blast search against the human genome to identify sequences with a best match to the human Y chromosome and to the female dog genome to identify those absent in the female genome. Candidate sequences were then tested for male specificity by PCR of five male and five female dogs. 32 sequences from the male genome, with a total length of 24 kbp, were identified as male specific, based on a match to the human Y chromosome, absence in the female dog genome and male specific PCR results. 14437 bp were then sequenced for 10 male dogs originating from Europe, Southwest Asia, Siberia, East Asia, Africa and America. Nine haplotypes were found, which were defined by 14 substitutions. The genetic distance between the haplotypes indicates that they originate from at least five wolf haplotypes. There was no obvious trend in the geographic distribution of the haplotypes. Conclusion: We have identified 24159 bp of dog Y-chromosome sequence to be used for population genetic studies. We sequenced 14437 bp in a worldwide collection of dogs, identifying 14 SNPs for future SNP analyses, and giving a first description of the dog Y-chromosome phylogeny.
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