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n this paper we report on the investigation of baryonic resonance production in proton-proton collisions at the kinetic energies of 1.25 GeV and 3.5 GeV, based on data measured with HADES. Exclusive channels npπ+ and ppπ0 as well as ppe+e− were studied simultaneously in the framework of a one-boson exchange model. The resonance cross sections were determined from the one-pion channels for Δ(1232) and N(1440) (1.25 GeV) as well as further Δ and N* resonances up to 2 GeV/c2 for the 3.5 GeV data. The data at 1.25 GeV energy were also analysed within the framework of the partial wave analysis together with the set of several other measurements at lower energies. The obtained solutions provided the evolution of resonance production with the beam energy, showing a sizeable non-resonant contribution but with still dominating contribution of Δ(1232)P33. In the case of 3.5 GeV data, the study of the ppe+e− channel gave the insight on the Dalitz decays of the baryon resonances and, in particular, on the electromagnetic transition form-factors in the time-like region. We show that the assumption of a constant electromagnetic transition form-factors leads to underestimation of the yield in the dielectron invariant mass spectrum below the vector mesons pole. On the other hand, a comparison with various transport models shows the important role of intermediate ρ production, though with a large model dependency. The exclusive channels analysis done by the HADES collaboration provides new stringent restrictions on the parameterizations used in the models.
his contribution aims to give a basic overview of the latest results regarding the production of resonances in different collision systems. The results were extracted from experimental data collected with HADES that is a multipurpose detector located at the GSI Helmholtzzentrum, Darmstadt. The main points discussed here are: the properties of the strange resonances Λ(1405) and Σ(1385), the role of Δ’s as a source of pions in the final state, the production dynamics reflected in form of differential cross sections, and the role of the ϕ meson as a source for K− particles.
The snake pipefish, Entelurus aequoreus (Linnaeus, 1758), is a slender, up to 60 cm long, northern Atlantic fish that dwells in open seagrass habitats and has recently expanded its distribution range. The snake pipefish is part of the family Syngnathidae (seahorses and pipefish) that has undergone several characteristic morphological changes, such as loss of pelvic fins and elongated snout. Here, we present a highly contiguous, near chromosome-scale genome of the snake pipefish assembled as part of a university master’s course. The final assembly has a length of 1.6 Gbp in 7,391 scaffolds, a scaffold and contig N50 of 62.3 Mbp and 45.0 Mbp and L50 of 12 and 14, respectively. The largest 28 scaffolds (>21 Mbp) span 89.7% of the assembly length. A BUSCO completeness score of 94.1% and a mapping rate above 98% suggest a high assembly completeness. Repetitive elements cover 74.93% of the genome, one of the highest proportions so far identified in vertebrate genomes. Demographic modeling using the PSMC framework indicates a peak in effective population size (50 – 100 kya) during the last interglacial period and suggests that the species might largely benefit from warmer water conditions, as seen today. Our updated snake pipefish assembly forms an important foundation for further analysis of the morphological and molecular changes unique to the family Syngnathidae.
The production of Σ0 baryons in the nuclear reaction p (3.5 GeV) + Nb (corresponding to sNN=3.18 GeV) is studied with the detector set-up HADES at GSI, Darmstadt. Σ0s were identified via the decay Σ0→Λγ with subsequent decays Λ→pπ− in coincidence with a e+e− pair from either external (γ→e+e−) or internal (Dalitz decay γ⁎→e+e−) gamma conversions. The differential Σ0 cross section integrated over the detector acceptance, i.e. the rapidity interval 0.5<y<1.1, has been extracted as ΔσΣ0=2.3±(0.2)stat±(−0.6+0.6)sys±(0.2)norm mb, yielding the inclusive production cross section in full phase space σΣ0total=5.8±(0.5)stat±(−1.4+1.4)sys±(0.6)norm±(1.7)extrapol mb by averaging over different extrapolation methods. The Λall/Σ0 ratio within the HADES acceptance is equal to 2.3±(0.2)stat±(−0.6+0.6)sys. The obtained rapidity and momentum distributions are compared to transport model calculations. The Σ0 yield agrees with the statistical model of particle production in nuclear reactions. Keywords: Hyperons, Strangeness, Proton, Nucleus.
Objective. A study supported by the EULAR and the ACR being conducted to establish classification criteria for polymyalgia rheumatica (PMR) will include ultrasound examination of the shoulders and hips. Ultrasound (US) depicts glenohumeral joint effusion, biceps tenosynovitis, subdeltoid bursitis, hip joint synovitis, and trochanteric bursitis in PMR. These findings may aid in distinguishing PMR from other diseases. The purpose of this study was to assess standards and US interreader agreement of participants in the PMR classification criteria study. Methods. Sixteen physicians in four groups examined shoulders and hips of 4 patients and 4 healthy adults with ultrasound. Overall agreement and interobserver agreement were calculated. Results. The overall agreement (OA) between groups was 87%. The OA for healthy shoulders was 88.8%, for healthy hips 100%, for shoulders with pathology 85.2%, and 74.3% for hips with pathology, respectively. Conclusion. There was a high degree of agreement found for the examination of healthy shoulders and pathologic hips. Agreement was moderate for pathologic shoulders and perfect for healthy hips. US of shoulder and hips performed by different examiners is a reliable and feasible tool for assessment of PMR related disease pathology and can be incorporated into a classification criteria study.
The lessons from QE and other 'unconventional' monetary policies - evidence from the Bank of England
(2011)
This paper investigates the effectiveness of the ‘quantitative easing’ policy, as implemented by the Bank of England in March 2009. Similar policies had been previously implemented in Japan, the U.S. and the Eurozone. The effectiveness is measured by the impact of Bank of England policies (including, but not limited to QE) on nominal GDP growth – the declared goal of the policy, according to the Bank of England. Unlike the majority of the literature on the topic, the general-to-specific econometric modeling methodology (a.k.a. the ‘Hendry’ or ‘LSE’ methodology) is employed for this purpose. The empirical analysis indicates that QE as defined and announced in March 2009 had no apparent effect on the UK economy. Meanwhile, it is found that a policy of ‘quantitative easing’ defined in the original sense of the term (Werner, 1994) is supported by empirical evidence: a stable relationship between a lending aggregate (disaggregated M4 lending, i.e. bank credit for GDP transactions) and nominal GDP is found. The findings imply that BoE policy should more directly target the growth of bank credit for GDP-transactions.
The unintended consequences of the debt ... will increased government expenditure hurt the economy?
(2011)
In 2008, governments in many countries embarked on large fiscal expenditure programmes, with the intention to support the economy and prevent a more serious recession. In this study, the overall impact of a substantial increase in fiscal expenditure is considered by providing a novel analysis of the most relevant recent experience in similar circumstances, namely that of Japan in the 1990s. Then a weak economy with risk-averse banks seemed to require some of the largest peacetime fiscal stimulation programmes on record, albeit with disappointing results. The explanations provided by the literature and their unsatisfactory empirical record are reviewed. An alternative explanation, derived from early Keynesian models on the ineffectiveness of fiscal policy is presented in the form of a modified Fisher-equation, which incorporates the recent findings in the credit view literature. The model postulates complete quantity crowding out. It is subjected to empirical tests, which were supportive. Thus evidence is found that fiscal policy, if not supported by suitable monetary policy, is likely to crowd out private sector demand, even in an environment of falling or near-zero interest rates. As a policy conclusion it is pointed out that by changing the funding strategy, complete crowding out can be avoided and a positive net effect produced. The proposed framework creates common ground between proponents of Keynesian views (as held, among others, by Blinder and Solow), monetarist views (as held in particular by Milton Friedman) and those of leading contemporary macroeconomists (such as Mankiw).
Central banks have recently introduced new policy initiatives, including a policy called ‘Quantitative Easing’ (QE). Since it has been argued by the Bank of England that “Standard economic models are of limited use in these unusual circumstances, and the empirical evidence is extremely limited” (Bank of England, 2009b), we have taken an entirely empirical approach and have focused on the QE-experience, on which substantial data is available, namely that of Japan (2001-2006). Recent literature on the effectiveness of QE has neglected any reference to final policy goals. In this paper, we adopt the view that ultimately effectiveness will be measured by whether it will be able to “boost spending” (Bank of England, 2009b) and “will ultimately be judged by their impact on the wider macroeconomy” (Bank of England, 2010). In line with a widely held view among leading macroeconomists from various persuasions, while attempting to stay agnostic and open-minded on the distribution of demand changes between real output and inflation, we have thus identified nominal GDP growth as the key final policy goal of monetary policy. The empirical research finds that the policy conducted by the Bank of Japan between 2001 and 2006 makes little empirical difference while an alternative policy targeting credit creation (the original definition of QE) would likely have been more successful.
Schistosomiasis is a severe neglected tropical disease caused by trematodes and transmitted by freshwater snails. Snails are known to be highly tolerant to agricultural pesticides. However, little attention has been paid to the ecological consequences of pesticide pollution in areas endemic for schistosomiasis, where people live in close contact with non-sanitized freshwaters. In complementary laboratory and field studies on Kenyan inland areas along Lake Victoria, we show that pesticide pollution is a major driver in increasing the occurrence of host snails and thus the risk of schistosomiasis transmission. In the laboratory, snails showed higher insecticide tolerance to commonly found pesticides than associated invertebrates, in particular to the neonicotinoid Imidacloprid and the organophosphate Diazinon. In the field, we demonstrated at 48 sites that snails were present exclusively in habitats characterized by pesticide pollution and eutrophication. Our analysis revealed that insensitive snails dominated over their less tolerant competitors. The study shows for the first time that in the field, pesticide concentrations considered “safe” in environmental risk assessment have indirect effects on human health. Thus we conclude there is a need for rethinking the environmental risk of low pesticide concentrations and of integrating agricultural mitigation measures in the control of schistosomiasis.
Bei den im Rahmen des Forschungsverbundes erfolgten faunistischen Untersuchungen stand die Charakterisierung der unterschiedlichen, vor allem aber der wertvollen Biotoptypen der Braunkohlenfolgelandschaft mit Hilfe der dort lebenden Tierarten bzw. Artengemeinschaften im Vordergrund. Es wurden Tiergruppen bearbeitet, die zum einen ein hohes indikatorisches Potential besitzen, zum anderen unterschiedliche ökologische Hierachieebenen repräsentieren. Eine Auswertung der Ergebnisse erfolgte zumeist auf der Ebene der Biotoptypengruppen (siehe Heyde; Jakob; Köck; Reuter im gleichen Heft).