| 1. |
- Barucca, G., et al.
(författare)
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The potential of Λ and Ξ- studies with PANDA at FAIR
- 2021
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Ingår i: European Physical Journal A. - : Springer Nature. - 1434-6001 .- 1434-601X. ; 57:4
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Tidskriftsartikel (refereegranskat)abstract
- The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: p¯ p→ Λ¯ Λ and p¯ p→ Ξ¯ +Ξ-. The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA.
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| 2. |
- Barucca, G., et al.
(författare)
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Study of excited Ξ baryons with the P¯ ANDA detector
- 2021
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Ingår i: European Physical Journal A. - : Springer Nature. - 1434-6001 .- 1434-601X. ; 57:4
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Tidskriftsartikel (refereegranskat)abstract
- The study of baryon excitation spectra provides insight into the inner structure of baryons. So far, most of the world-wide efforts have been directed towards N∗ and Δ spectroscopy. Nevertheless, the study of the double and triple strange baryon spectrum provides independent information to the N∗ and Δ spectra. The future antiproton experiment P¯ANDA will provide direct access to final states containing a Ξ¯ Ξ pair, for which production cross sections up to μb are expected in p¯p reactions. With a luminosity of L= 10 31 cm- 2 s- 1 in the first phase of the experiment, the expected cross sections correspond to a production rate of ∼106events/day. With a nearly 4 π detector acceptance, P¯ANDA will thus be a hyperon factory. In this study, reactions of the type p¯p → Ξ¯ +Ξ∗ - as well as p¯p → Ξ¯ ∗ +Ξ- with various decay modes are investigated. For the exclusive reconstruction of the signal events a full decay tree fit is used, resulting in reconstruction efficiencies between 3 and 5%. This allows high statistics data to be collected within a few weeks of data taking.
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| 3. |
- Gross, C. P., et al.
(författare)
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The biogeography of community assembly: latitude and predation drive variation in community trait distribution in a guild of epifaunal crustaceans
- 2022
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Ingår i: Proceedings of the Royal Society B: Biological Sciences. - : The Royal Society. - 1471-2954 .- 0962-8452. ; 289:1969
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Tidskriftsartikel (refereegranskat)abstract
- While considerable evidence exists of biogeographic patterns in the intensity of species interactions, the influence of these patterns on variation in community structure is less clear. Studying how the distributions of traits in communities vary along global gradients can inform how variation in interactions and other factors contribute to the process of community assembly. Using a model selection approach on measures of trait dispersion in crustaceans associated with eelgrass (Zostera marina) spanning 30° of latitude in two oceans, we found that dispersion strongly increased with increasing predation and decreasing latitude. Ocean and epiphyte load appeared as secondary predictors; Pacific communities were more overdispersed while Atlantic communities were more clustered, and increasing epiphytes were associated with increased clustering. By examining how species interactions and environmental filters influence community structure across biogeographic regions, we demonstrate how both latitudinal variation in species interactions and historical contingency shape these responses. Community trait distributions have implications for ecosystem stability and functioning, and integrating large-scale observations of environmental filters, species interactions and traits can help us predict how communities may respond to environmental change.
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| 4. |
- Grosche, S, et al.
(författare)
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Rare variant analysis in eczema identifies exonic variants in DUSP1, NOTCH4 and SLC9A4
- 2021
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 12:1, s. 6618-
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Tidskriftsartikel (refereegranskat)abstract
- Previous genome-wide association studies revealed multiple common variants involved in eczema but the role of rare variants remains to be elucidated. Here, we investigate the role of rare variants in eczema susceptibility. We meta-analyze 21 study populations including 20,016 eczema cases and 380,433 controls. Rare variants are imputed with high accuracy using large population-based reference panels. We identify rare exonic variants in DUSP1, NOTCH4, and SLC9A4 to be associated with eczema. In DUSP1 and NOTCH4 missense variants are predicted to impact conserved functional domains. In addition, five novel common variants at SATB1-AS1/KCNH8, TRIB1/LINC00861, ZBTB1, TBX21/OSBPL7, and CSF2RB are discovered. While genes prioritized based on rare variants are significantly up-regulated in the skin, common variants point to immune cell function. Over 20% of the single nucleotide variant-based heritability is attributable to rare and low-frequency variants. The identified rare/low-frequency variants located in functional protein domains point to promising targets for novel therapeutic approaches to eczema.
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| 5. |
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| 6. |
- Maican, Florin G., 1975, et al.
(författare)
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The Dynamic Impact of Exporting on Firm R&D Investment
- 2023
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Ingår i: Journal of the European Economic Association. - : Oxford University Press (OUP). - 1542-4766 .- 1542-4774. ; 21:4, s. 1318-1362
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Tidskriftsartikel (refereegranskat)abstract
- This article estimates a dynamic structural model of firm R&D investment in twelve Swedish manufacturing industries and uses it to measure rates of return to R&D and to simulate the impact of trade restrictions on the investment incentives. Export market profits are a substantial source of the expected return to R&D. R&D spending is found to have a larger impact on firm productivity in the export market than in the domestic market. Counterfactual simulations show that trade restrictions lower both the expected return to R&D and R&D investment level, thus reducing an important source of the dynamic gains from trade. A 10% tariff on Swedish exports reduces the expected benefits of R&D for the median firm by 18.6% and lowers the amount of R&D spending by 7.6% in the high-tech industries. The corresponding reductions in the low-tech industries are 20.6% and 5.5%, respectively. R&D adjustments in response to export tariffs mainly occur on the intensive, rather than the extensive, margin.
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| 7. |
- Deter, HC, et al.
(författare)
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Does Anxiety Affect Survival in Patients with Coronary Heart Disease?
- 2023
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Ingår i: Journal of clinical medicine. - : MDPI AG. - 2077-0383. ; 12:6
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Behavioral and physiological risk factors worsen the prognosis of coronary heart disease (CHD). Anxiety is known to be a psychological predictor of CHD. In this study, we investigated whether this factor is associated with all-cause mortality in CHD patients in the long term. Methods: We studied 180 patients (mean age 60.6 SD 9.2 years, 26% women) with CHD from the Berlin Anxiety Trial (BAT) and the Stepwise Psychotherapy Intervention for Reducing Risk in Coronary Artery Disease (SPIRR-CAD) study. Their cardiac and psychological risk profile was represented by standardized procedures, including the Hospital Anxiety and Depression Scale (HADS) questionnaire. Mortality outcomes were assessed using a community-based registry. Results: Of 180 patients, we obtained information on all-cause mortality in 175 (96.7%) after a mean follow-up of 12.2 years (range 10.4–16.6 years). Of all participants, 54.4% had prior myocardial infarction, 95.3% had percutaneous transluminal coronary angioplasty and 22.2% had prior coronary artery bypass graft. Most of the patients (98.4%) had New York Heart Association class I and II, 25.6% had diabetes and 38.2% were smokers. Patients had a mean HADS anxiety score of 9.7 SD 4.1 at study entrance. We found the highest HADS anxiety quartile all-cause mortality in 14%, 30.2% in the middle quartiles and 58.7% in the lowest quartile (chi2 20.8, p = 0.001). Related to psychological mechanisms, a low level of anxiety, seemed to be a significant predictor of all-cause mortality. We found no advantage for patients who had received psychosocial therapy in terms of survival. Conclusion: These first data confirmed our hypothesis about the association of psychological risk factors with the long-term outcome of CAD patients. Future studies will clarify whether the severity of disease, age or a particular type of coping or denial mechanism are associated with the presented outcome in low-anxious patients.
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| 8. |
- Duffy, J. Emmett, et al.
(författare)
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A Pleistocene legacy structures variation in modern seagrass ecosystems
- 2022
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 119:32
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Tidskriftsartikel (refereegranskat)abstract
- Distribution of Earth's biomes is structured by the match between climate and plant traits, which in turn shape associated communities and ecosystem processes and services. However, that climate-trait match can be disrupted by historical events, with lasting ecosystem impacts. As Earth's environment changes faster than at any time in human history, critical questions are whether and how organismal traits and ecosystems can adjust to altered conditions. We quantified the relative importance of current environmental forcing versus evolutionary history in shaping the growth form (stature and biomass) and associated community of eelgrass (Zostera marina), a widespread foundation plant of marine ecosystems along Northern Hemisphere coastlines, which experienced major shifts in distribution and genetic composition during the Pleistocene. We found that eelgrass stature and biomass retain a legacy of the Pleistocene colonization of the Atlantic from the ancestral Pacific range and of more recent within-basin bottlenecks and genetic differentiation. This evolutionary legacy in turn influences the biomass of associated algae and invertebrates that fuel coastal food webs, with effects comparable to or stronger than effects of current environmental forcing. Such historical lags in phenotypic acclimatization may constrain ecosystem adjustments to rapid anthropogenic climate change, thus altering predictions about the future functioning of ecosystems.
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| 9. |
- Maican, Florin G., 1975, et al.
(författare)
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Determinants of economies of scope in retail & nbsp
- 2021
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Ingår i: International Journal of Industrial Organization. - : Elsevier BV. - 0167-7187. ; 75
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Tidskriftsartikel (refereegranskat)abstract
- This paper studies the determinants of economies of scope and quantifies their impact on the extensive and intensive product margins in retail. We use a framework based on a multiproduct technology to model stores & rsquo; incentives to expand product variety. Using novel Swedish data on product categories and stores, we find that high-productivity stores offer more product categories and sell more products of all categories. Stores with high-demand shocks specialize in fewer product categories and sell more products of top selling categories. Policy simulations of regional programs that target the determinants of economies of scope show that investment subsidies and mentoring support for low productivity stores increase the number of product categories and sales per product category, especially benefiting stores in rural markets. (c) 2021 Elsevier B.V. All rights reserved.
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| 10. |
- Pawłowski, P., et al.
(författare)
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Neutrons from projectile fragmentation at 600 MeV/nucleon
- 2023
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Ingår i: Physical Review C. - 2469-9993 .- 2469-9985. ; 108:4
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Tidskriftsartikel (refereegranskat)abstract
- The neutron emission in projectile fragmentation at relativistic energies was studied with the Large-Area-Neutron-Detector LAND coupled to the ALADIN forward spectrometer at the GSI Schwerionen-Synchrotron (SIS). Stable Sn124 and radioactive Sn107 and La124 beams with an incident energy of 600 MeV/nucleon were used to explore the N/Z dependence of the identified neutron source. A cluster-recognition algorithm is applied for identifying individual particles within the hit distributions registered with LAND. The obtained momentum distributions are extrapolated over the full phase space occupied by the neutrons from the projectile-spectator source. The mean multiplicities of spectator neutrons reach values of up to about 11 and depend strongly on the isotopic composition of the projectile. An effective source temperature of T≈2-5 MeV, monotonically increasing with decreasing impact parameter, is deduced from the transverse momentum distributions. For the interpretation of the data, calculations with the statistical multifragmentation model were performed. The variety of excited projectile spectators assumed to decay statistically is represented by an ensemble of excited sources with parameters determined previously from the fragment production observed in the same experiments. The obtained agreement is very satisfactory for more peripheral collisions where, according to the model, neutrons are mainly emitted during the secondary decays of excited fragments. The neutron multiplicity in more central collisions is underestimated, indicating that other sources besides the modeled statistical breakup contribute to the observed neutron yield. The choice made for the symmetry-term coefficient of the liquid-drop description of produced fragments has a weak effect on the predicted neutron multiplicities.
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