| 1. |
- Aad, G., et al.
(författare)
-
- 2010
-
swepub:Mat__t
|
|
| 2. |
- Aad, G., et al.
(författare)
-
- 2010
-
swepub:Mat__t
|
|
| 3. |
- Aad, G., et al.
(författare)
-
- 2010
-
swepub:Mat__t
|
|
| 4. |
- Aad, G., et al.
(författare)
-
- 2010
-
swepub:Mat__t
|
|
| 5. |
|
|
| 6. |
- Aad, G., et al.
(författare)
-
- 2011
-
swepub:Mat__t
|
|
| 7. |
- Glasbey, JC, et al.
(författare)
-
- 2021
-
swepub:Mat__t
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
| 11. |
- Abt, I, et al.
(författare)
-
Inclusive V-0 production cross sections from 920 GeV fixed target proton-nucleus collisions
- 2003
-
Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 29:2, s. 181-190
-
Tidskriftsartikel (refereegranskat)abstract
- Inclusive differential cross sections dsigma(pA)/dx(F) and dsigma(pA)/dp(t)(2) for the production of K-S(0), Lambda, and (&ULambda;) over bar particles are measured at HERA in proton-induced reactions on C, Al, Ti, and W targets. The incident beam energy is 920 GeV, corresponding to roots = 41.6 GeV in the proton-nucleon system. The ratios of differential cross sections dsigma(pA)(K-S(0))/dsigma(pA)(Lambda) and dsigma(pA)((&ULambda;) over bar)/dsigma(pA) (Lambda) are measured to be 6.2 +/- 0.5 and 0.66 +/- 0.07, respectively, for x(F) approximate to -0.06. No significant dependence upon the target material is observed. Within errors, the slopes of the transverse momentum distributions da,Ald t also show no significant dependence upon the target material. The dependence of the extrapolated total cross sections sigma(pA) on the atomic mass A of the target material is discussed, and the deduced cross sections per nucleon sigma(pN) are compared with results obtained at other energies.
|
|
| 12. |
- Abt, I, et al.
(författare)
-
Measurement of the b(b)over-bar production cross section in 920 GeV fixed-target proton-nucleus collisions
- 2003
-
Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 26:3, s. 345-355
-
Tidskriftsartikel (refereegranskat)abstract
- Using the HERA-B detector, the b (b) over bar production cross section has been measured in 920 GeV proton collisions on carbon and titanium targets. The b (b) over bar production was tagged via inclusive bottom quark decays into J/psi by exploiting the longitudinal separation of J/psi --> l(+)l(-) decay vertices from the primary proton-nucleus interaction. Both e(+)e(-) and mu(+)mu(-) channels have been reconstructed and the combined analysis yields the cross section sigma(b (b) over bar) = 32(-12)(+14)(stat) (+6)(-7)(sys) nb/nucleon.
|
|
| 13. |
- Kjellsson, Ludvig, et al.
(författare)
-
Resonant Inelastic X-Ray Scattering Reveals Hidden Local Transitions of the Aqueous OH Radical
- 2020
-
Ingår i: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 124:23
-
Tidskriftsartikel (refereegranskat)abstract
- Resonant inelastic x-ray scattering (RIXS) provides remarkable opportunities to interrogate ultra-fast dynamics in liquids. Here we use RIXS to study the fundamentally and practically important hydroxyl radical in liquid water, OH(aq). Impulsive ionization of pure liquid water produced a short-lived population of OH(aq), which was probed using femtosecond x-rays from an x-ray free-electron laser. We find that RIXS reveals localized electronic transitions that are masked in the ultraviolet absorption spectrum by strong charge-transfer transitions-thus providing a means to investigate the evolving electronic structure and reactivity of the hydroxyl radical in aqueous and heterogeneous environments. First-principles calculations provide interpretation of the main spectral features.
|
|
| 14. |
- Loh, Z-H, et al.
(författare)
-
Observation of the fastest chemical processes in the radiolysis of water
- 2020
-
Ingår i: Science. - : AMER ASSOC ADVANCEMENT SCIENCE. - 0036-8075 .- 1095-9203. ; 367:6474, s. 179-182
-
Tidskriftsartikel (refereegranskat)abstract
- Elementary processes associated with ionization of liquid water provide a framework for understanding radiation-matter interactions in chemistry and biology. Although numerous studies have been conducted on the dynamics of the hydrated electron, its partner arising from ionization of liquid water, H2O+, remains elusive. We used tunable femtosecond soft x-ray pulses from an x-ray free electron laser to reveal the dynamics of the valence hole created by strong-field ionization and to track the primary proton transfer reaction giving rise to the formation of OH. The isolated resonance associated with the valence hole (H2O+/OH) enabled straightforward detection. Molecular dynamics simulations revealed that the x-ray spectra are sensitive to structural dynamics at the ionization site. We found signatures of hydrated-electron dynamics in the x-ray spectrum.
|
|
| 15. |
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
|
|
| 19. |
- Cronin, Thomas M., et al.
(författare)
-
Interglacial Paleoclimate in the Arctic
- 2019
-
Ingår i: Paleoceanography and Paleoclimatology. - 2572-4517 .- 2572-4525. ; 34:12, s. 1959-1979
-
Tidskriftsartikel (refereegranskat)abstract
- Marine Isotope Stage 11 from similar to 424 to 374 ka experienced peak interglacial warmth and highest global sea level similar to 410-400 ka. MIS 11 has received extensive study on the causes of its long duration and warmer than Holocene climate, which is anomalous in the last half million years. However, a major geographic gap in MIS 11 proxy records exists in the Arctic Ocean where fragmentary evidence exists for a seasonally sea ice-free summers and high sea-surface temperatures (SST; similar to 8-10 degrees C near the Mendeleev Ridge). We investigated MIS 11 in the western and central Arctic Ocean using 12 piston cores and several shorter cores using proxies for surface productivity (microfossil density), bottom water temperature (magnesium/calcium ratios), the proportion of Arctic Ocean Deep Water versus Arctic Intermediate Water (key ostracode species), sea ice (epipelagic sea ice dwelling ostracode abundance), and SST (planktic foraminifers). We produced a new benthic foraminiferal delta O-18 curve, which signifies changes in global ice volume, Arctic Ocean bottom temperature, and perhaps local oceanographic changes. Results indicate that peak warmth occurred in the Amerasian Basin during the middle of MIS 11 roughly from 410 to 400 ka. SST were as high as 8-10 degrees C for peak interglacial warmth, and sea ice was absent in summers. Evidence also exists for abrupt suborbital events punctuating the MIS 12-MIS 11-MIS 10 interval. These fluctuations in productivity, bottom water temperature, and deep and intermediate water masses (Arctic Ocean Deep Water and Arctic Intermediate Water) may represent Heinrich-like events possibly involving extensive ice shelves extending off Laurentide and Fennoscandian Ice Sheets bordering the Arctic.
|
|
| 20. |
- Farmer, Jesse R., et al.
(författare)
-
A 600 kyr reconstruction of deep Arctic seawater δ18O from benthic foraminiferal δ18O and ostracode Mg / Ca paleothermometry
- 2023
-
Ingår i: Climate of the Past. - : Copernicus GmbH. - 1814-9324 .- 1814-9332. ; 19:3, s. 555-578
-
Tidskriftsartikel (refereegranskat)abstract
- The oxygen isotopic composition of benthic foraminiferal tests (δ18Ob) is one of the pre-eminent tools for correlating marine sediments and interpreting past terrestrial ice volume and deep-ocean temperatures. Despite the prevalence of δ18Ob applications to marine sediment cores over the Quaternary, its use is limited in the Arctic Ocean because of low benthic foraminiferal abundances, challenges with constructing independent sediment core age models, and an apparent muted amplitude of Arctic δ18Ob variability compared to open-ocean records. Here we evaluate the controls on Arctic δ18Ob by using ostracode paleothermometry to generate a composite record of the δ18O of seawater (δ18Osw) from 12 sediment cores in the intermediate to deep Arctic Ocean (700–2700 m) that covers the last 600 kyr based on biostratigraphy and orbitally tuned age models. Results show that Arctic δ18Ob was generally higher than open-ocean δ18Ob during interglacials but was generally equivalent to global reference records during glacial periods. The reduced glacial–interglacial Arctic δ18Ob range resulted in part from the opposing effect of temperature, with intermediate to deep Arctic warming during glacials counteracting the whole-ocean δ18Osw increase from expanded terrestrial ice sheets. After removing the temperature effect from δ18Ob, we find that the intermediate to deep Arctic experienced large (≥1 ‰) variations in local δ18Osw, with generally higher local δ18Osw during interglacials and lower δ18Osw during glacials. Both the magnitude and timing of low local δ18Osw intervals are inconsistent with the recent proposal of freshwater intervals in the Arctic Ocean during past glaciations. Instead, we suggest that lower local δ18Osw in the intermediate to deep Arctic Ocean during glaciations reflected weaker upper-ocean stratification and more efficient transport of low-δ18Osw Arctic surface waters to depth by mixing and/or brine rejection.
|
|
| 21. |
|
|
| 22. |
- Hellmuth, Marc, 1980-, et al.
(författare)
-
Clustering systems of phylogenetic networks
- 2023
-
Ingår i: Theory in biosciences. - 1431-7613 .- 1611-7530. ; :142, s. 301-358
-
Tidskriftsartikel (refereegranskat)abstract
- Rooted acyclic graphs appear naturally when the phylogenetic relationship of a set X of taxa involves not only speciations but also recombination, horizontal transfer, or hybridization that cannot be captured by trees. A variety of classes of such networks have been discussed in the literature, including phylogenetic, level-1, tree-child, tree-based, galled tree, regular, or normal networks as models of different types of evolutionary processes. Clusters arise in models of phylogeny as the sets C(v) of descendant taxa of a vertex v. The clustering system CN comprising the clusters of a network N conveys key information on N itself. In the special case of rooted phylogenetic trees, T is uniquely determined by its clustering system CT. Although this is no longer true for networks in general, it is of interest to relate properties of N and CN. Here, we systematically investigate the relationships of several well-studied classes of networks and their clustering systems. The main results are correspondences of classes of networks and clustering systems of the following form: If N is a network of type X, then CN satisfies Y, and conversely if C is a clustering system satisfying Y, then there is network N of type X such that C⊆CN.This, in turn, allows us to investigate the mutual dependencies between the distinct types of networks in much detail.
|
|
| 23. |
- Hellmuth, Marc, et al.
(författare)
-
Combining Orthology and Xenology Data in a Common Phylogenetic Tree
- 2021
-
Ingår i: Advances in Bioinformatics and Computational Biology. - Cham : Springer. - 9783030918132 - 9783030918149 ; , s. 53-64
-
Konferensbidrag (refereegranskat)abstract
- In mathematical phylogenetics, types of events in a gene tree T are formalized by vertex labels t(v) and set-valued edge labels λ(e). The orthology and paralogy relations between genes are a special case of a map δ on the pairs of leaves of T defined by δ(x,y)=q if the last common ancestor lca(x,y) of x and y is labeled by an event type q, e.g., speciation or duplication. Similarly, a map εε with m∈ε(x,y) if m∈λ(e) for at least one edge e along the path from lca(x,y) to y generalizes xenology, i.e., horizontal gene transfer. We show that a pair of maps (δ,ε) derives from a tree (T,t,λ) in this manner if and only if there exists a common refinement of the (unique) least-resolved vertex labeled tree (Tδ,tδ) that explains δ and the (unique) least-resolved edge labeled tree (Tε,λε) that explains ε (provided both trees exist). This result remains true if certain combinations of labels at incident vertices and edges are forbidden.
|
|
| 24. |
- Hellmuth, Marc, et al.
(författare)
-
Compatibility of partitions with trees, hierarchies, and split systems
- 2022
-
Ingår i: Discrete Applied Mathematics. - : Elsevier BV. - 0166-218X .- 1872-6771. ; 314, s. 265-283
-
Tidskriftsartikel (refereegranskat)abstract
- The question whether a partition P and a hierarchy H or a tree-like split system S are compatible naturally arises in a wide range of classification problems. In the setting of phylogenetic trees, one asks whether the sets of P coincide with leaf sets of connected components obtained by deleting some edges from the tree T that represents H or S, respectively. More generally, we ask whether a refinement T∗ of T exists such that T∗ and P are compatible in this sense. The latter is closely related to the question as to whether there exists a tree at all that is compatible with P. We report several characterizations for (refinements of) hierarchies and split systems that are compatible with (systems of) partitions. In addition, we provide a linear-time algorithm to check whether refinements of trees and a given partition are compatible. The latter problem becomes NP-complete but fixed-parameter tractable if a system of partitions is considered instead of a single partition. In this context, we also explore the close relationship of the concept of compatibility and so-called Fitch maps.
|
|
| 25. |
- Jadersten, M., et al.
(författare)
-
Targeting SAMHD1 with hydroxyurea in first-line cytarabine-based therapy of newly diagnosed acute myeloid leukaemia: Results from the HEAT-AML trial
- 2022
-
Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 292:6, s. 925-940
-
Tidskriftsartikel (refereegranskat)abstract
- Background Treatment of newly diagnosed acute myeloid leukaemia (AML) is based on combination chemotherapy with cytarabine (ara-C) and anthracyclines. Five-year overall survival is below 30%, which has partly been attributed to cytarabine resistance. Preclinical data suggest that the addition of hydroxyurea potentiates cytarabine efficacy by increasing ara-C triphosphate (ara-CTP) levels through targeted inhibition of SAMHD1. Objectives In this phase 1 trial, we evaluated the feasibility, safety and efficacy of the addition of hydroxyurea to standard chemotherapy with cytarabine/daunorubicin in newly diagnosed AML patients. Methods Nine patients were enrolled and received at least two courses of ara-C (1 g/m(2)/2 h b.i.d. d1-5, i.e., a total of 10 g/m(2) per course), hydroxyurea (1-2 g d1-5) and daunorubicin (60 mg/m(2) d1-3). The primary endpoint was safety; secondary endpoints were complete remission rate and measurable residual disease (MRD). Additionally, pharmacokinetic studies of ara-CTP and ex vivo drug sensitivity assays were performed. Results The most common grade 3-4 toxicity was febrile neutropenia (100%). No unexpected toxicities were observed. Pharmacokinetic analyses showed a significant increase in median ara-CTP levels (1.5-fold; p = 0.04) in patients receiving doses of 1 g hydroxyurea. Ex vivo, diagnostic leukaemic bone marrow blasts from study patients were significantly sensitised to ara-C by a median factor of 2.1 (p = 0.0047). All nine patients (100%) achieved complete remission, and all eight (100%) with validated MRD measurements (flow cytometry or real-time quantitative polymerase chain reaction [RT-qPCR]) had an MRD level <0.1% after two cycles of chemotherapy. Treatment was well-tolerated, and median time to neutrophil recovery >1.0 x 10(9)/L and to platelet recovery >50 x 10(9)/L after the start of cycle 1 was 19 days and 22 days, respectively. Six of nine patients underwent allogeneic haematopoietic stem-cell transplantation (allo-HSCT). With a median follow-up of 18.0 (range 14.9-20.5) months, one patient with adverse risk not fit for HSCT experienced a relapse after 11.9 months but is now in second complete remission. Conclusion Targeted inhibition of SAMHD1 by the addition of hydroxyurea to conventional AML therapy is safe and appears efficacious within the limitations of the small phase 1 patient cohort. These results need to be corroborated in a larger study.
|
|
