Report of the 2023 Season

The second excavation campaign at the Gymnasium of Agrigento aimed to resolve lingering questions regarding the gymnasium's extension and construction date. Results of both excavation seasons (2022, 2023) unveiled a stenopos running west of the race-track complex and pool, excavated for a length of 23 m. Noteworthy discoveries included the northwest corner of the gymnasium's insula and eight monumental walls on two terraces, suggestive of a substantial architectural complex. These structures exhibited characteristics consistent with the palaestra, supported by findings such as a stamped roof tile with the letters ΓΥΜ and evidence of a valve system and lead pipes in a room north of the pool

Report of the 2022 Season

The Gymnasium of Agrigento has been excavated between the 1950s and 2005. While parts of a race-track section and a pool were revealed between two stenopoi, the extension of the gymnasium and the existence of a palaestra as well as the construction date could not be securely determined. A project launched in 2019 in cooperation between the Parco Archeologico e Paesaggistico Valle dei Templi di Agrigento and the Freie Universität Berlin aims to solve these questions. Based on the results of a geophysical survey, four trenches were excavated in 2022 in a field to the north of the pool where the palaestra was most likely located

Tönerne Rundaltäre aus Sizilien

Cylindrical altars made of terracotta, called arulae, are common finds in Hellenistic Sicily. They were used there and in southern Italy from the late fourth to the first century BC. Their heyday is in the third century BC, as then they were gradually replaced by built altars in the second/first century BC. Arulae were most often found in domestic contexts and are much less frequently encountered in sanctuaries. Their size, weight and shape suggest that they were portable and could be used flexibly in different settings, and that they carried shallow ceramic bowls for making offerings (libations, food, or incense?). However, since they are usually found in a fragmentary condition, scholars have paid little attention to them. This paper provides the first comprehensive study of these altars from Sicily, focusing on their size, shape, decoration, typology, geographical and chronological distribution. Furthermore, their function and spatial contexts are discussed, with as special emphasis on the arulae found during recent excavations in the House of the Two Skeletons at Morgantina

New Research at the Gymnasium of Agrigento

The gymnasium of Agrigento is one of the most important, if not the most important gymnasium in Sicily and the western Mediterranean more generally, because of its size, design, and chronology. While parts of a race-track section and a pool were excavated between the 1950s and 2005 and were published in 2009 and 2011, crucial questions remain open: the extension, design, and most notably the existence and location of a palaestra; the construction date in the 2nd century B.C. or the Augustan period; and the urban context. To answer these questions, a project was launched in 2019 in cooperation between the Parco Archeologico e Paesaggistico Valle dei Templi di Agrigento and the Freie Universität Berlin, and a first season, together with the British School at Rome, was carried out in 2020. This paper presents the results of this first campaign, which included first, a geophysical survey of the area around the gymnasium and of a field to the north of the Hellenistic-Roman temple; and second, an architectural survey of unpublished features and work in the archives and storerooms of the Parco Archeologico

Role of quantum fluctuations in a system with strong fields: Onset of hydrodynamical flow

Quantum fluctuations are believed to play an important role in the thermalization of classical fields in inflationary cosmology but their relevance for isotropization/thermalization of the classical fields produced in heavy ion collisions is not completely understood. We consider a scalar $\phi^4$ toy model coupled to a strong external source, like in the Color Glass Condensate description of the early time dynamics of ultrarelativistic heavy ion collisions. The leading order classical evolution of the scalar fields is significantly modified by the rapid growth of time-dependent quantum fluctuations, necessitating an all order resummation of such "secular" terms. We show that the resummed expressions cause the system to evolve in accordance with ideal hydrodynamics. We comment briefly on the thermalization of our quantum system and the extension of our results to a gauge theory.Comment: 45 pages, 17 figure

Role of quantum fluctuations in a system with strong fields: Spectral properties and Thermalization

In a previous work [arXiv:1009.4363], we have studied the evolution of a scalar field with a quartic coupling, driven by a classical source that initializes it to a non-perturbatively large value. At leading order in the coupling, the evolution of this system is given by classical solutions of the field equation of motion. However, this system is subject to a parametric resonance that leads to secular divergences in higher order corrections to physical observables. We have proposed a scheme that resums all the leading secular terms: this resummation leads to finite results at all times, and we have observed also that it makes the pressure tensor of the system relax to its equilibrium value. In the present paper, we continue the study of this system by looking at finer details of its dynamics. We first compute its spectral function at various stages of the evolution, and we observe that after a fairly short transient time there are well defined massive quasi-particles. We then consider the time evolution of the momentum distribution of these quasi-particles, and we show that after a stage dominated by the parametric resonance, this distribution slowly evolves to an equilibrium distribution. Interestingly, this distribution develops a transient chemical potential, signalling the fact that number changing processes are much slower than the elastic ones.Comment: 36 pages, 19 figures, version to appear in Nucl. Phys.

Production of Photons and Dileptons in the Glasma

We study the production of photons and dileptons during the pre-equilibrium Glasma stage in heavy ion collisions and discuss the implications in light of the PHENIX data. We find that the measured distributions of such electromagnetic emissions, while having some features not well understood if hypothesized to entirely arise from a thermalized Quark-Gluon Plasma, have some qualitative features that might be described after including effects from a thermalizing Glasma. The shape and centrality dependence of the transverse momentum spectra of the so-called "thermal photons" are well described. The mass and transverse momentum dependence of intermediate mass dileptons also agree with our estimates. The low transverse momenta from which the excessive dileptons (in low to intermediate mass region) arise is suggestive of emissions from a Bose condensate. We also predict the centrality dependence of dilepton production. Uncertainties in the current approach and improvements in the future are discussed.Comment: 24 pages, 7 figures, new results and references added in v

Henchir Bourgou (Djerba, Tunesien): Stratigraphie und Fundvorlage einer Sondage im Zentrum der antiken Siedlung (8. Jh. v. Chr. – 2. Jh. n. Chr.)

Die antike Siedlung Henchir Bourgou auf Djerba (Tunesien) ist seit 2017 Gegenstand gemeinsamer Forschungen des tunesischen Institut National du Patrimoine (INP) und des Deutschen Archäologischen Instituts (DAI). Der vorliegende Beitrag ist die Publikation der Ergebnisse einer ersten Sondage im Zentrum des Siedlungsareals. Die Schichtenabfolge und die Baubefunde von den ersten Siedlungsphasen im 8. Jh. v. Chr. bis zu den letzten Spuren einer intensiven Besiedlung an der höchsten Stelle des Siedlungsareals in der letzten Hälfte des 2. Jhs. n. Chr., geben gemeinsam mit der vorgelegten Fundkeramik und begleitenden naturwissenschaftlichen Untersuchungen einen ersten Überblick über die Siedlungs- und Wirtschaftsgeschichte von Henchir Bourgou.The ancient settlement of Henchir Bourgou/Djerba (Tunisia) has been the focus of joint research by the Tunisian Institut National du Patrimoine (INP) and the German Archaeological Institute (DAI) since 2017. The article summarizes the results of a first sondage in the centre of the settlement area. The sequence of layers and the building features from the first settlement phases in the 8th century B.C. to the last traces of intensive occupation at the highest point of the settlement area in the last half of the 2nd century A.D., together with the find pottery and accompanying scientific investigations, provide a first overview of the settlement and economic history of Henchir Bourgou

Model parameterization to simulate and compare the PAR absorption potential of two competing plant species

Mountain pastures dominated by the pasture grass Setaria sphacelata in the Andes of southern Ecuador are heavily infested by southern bracken (Pteridium arachnoideum), a major problem for pasture management. Field observations suggest that bracken might outcompete the grass due to its competitive strength with regard to the absorption of photosynthetically active radiation (PAR). To understand the PAR absorption potential of both species, the aims of the current paper are to (1) parameterize a radiation scheme of a two-big-leaf model by deriving structural (LAI, leaf angle parameter) and optical (leaf albedo, transmittance) plant traits for average individuals from field surveys, (2) to initialize the properly parameterized radiation scheme with realistic global irradiation conditions of the Rio San Francisco Valley in the Andes of southern Ecuador, and (3) to compare the PAR absorption capabilities of both species under typical local weather conditions. Field data show that bracken reveals a slightly higher average leaf area index (LAI) and more horizontally oriented leaves in comparison to Setaria. Spectrometer measurements reveal that bracken and Setaria are characterized by a similar average leaf absorptance. Simulations with the average diurnal course of incoming solar radiation (1998–2005) and the mean leaf–sun geometry reveal that PAR absorption is fairly equal for both species. However, the comparison of typical clear and overcast days show that two parameters, (1) the relation of incoming diffuse and direct irradiance, and (2) the leaf–sun geometry play a major role for PAR absorption in the two-big-leaf approach: Under cloudy sky conditions (mainly diffuse irradiance), PAR absorption is slightly higher for Setaria while under clear sky conditions (mainly direct irradiance), the average bracken individual is characterized by a higher PAR absorption potential. (∼74 MJ m−2 year−1). The latter situation which occurs if the maximum daily irradiance exceeds 615 W m−2 is mainly due to the nearly orthogonal incidence of the direct solar beam onto the horizontally oriented frond area which implies a high amount of direct PAR absorption during the noon maximum of direct irradiance. Such situations of solar irradiance favoring a higher PAR absorptance of bracken occur in ∼36% of the observation period (1998–2005). By considering the annual course of PAR irradiance in the San Francisco Valley, the clear advantage of bracken on clear days (36% of all days) is completely compensated by the slight but more frequent advantage of Setaria under overcast conditions (64% of all days). This means that neither bracken nor Setaria show a distinct advantage in PAR absorption capability under the current climatic conditions of the study area

Thrombocytopenia and platelet transfusions in ICU patients: an international inception cohort study (PLOT-ICU)

Purpose Thrombocytopenia (platelet count < 150 × 109/L) is common in intensive care unit (ICU) patients and is likely associated with worse outcomes. In this study we present international contemporary data on thrombocytopenia in ICU patients. Methods We conducted a prospective cohort study in adult ICU patients in 52 ICUs across 10 countries. We assessed frequencies of thrombocytopenia, use of platelet transfusions and clinical outcomes including mortality. We evaluated pre-selected potential risk factors for the development of thrombocytopenia during ICU stay and associations between thrombocytopenia at ICU admission and 90-day mortality using pre-specified logistic regression analyses. Results We analysed 1166 ICU patients; the median age was 63 years and 39.5% were female. Overall, 43.2% (95% confidence interval (CI) 40.4–46.1) had thrombocytopenia; 23.4% (20–26) had thrombocytopenia at ICU admission, and 19.8% (17.6–22.2) developed thrombocytopenia during their ICU stay. Non-AIDS-, non-cancer-related immune deficiency, liver failure, male sex, septic shock, and bleeding at ICU admission were associated with the development of thrombocytopenia during ICU stay. Among patients with thrombocytopenia, 22.6% received platelet transfusion(s), and 64.3% of in-ICU transfusions were prophylactic. Patients with thrombocytopenia had higher occurrences of bleeding and death, fewer days alive without the use of life-support, and fewer days alive and out of hospital. Thrombocytopenia at ICU admission was associated with 90-day mortality (adjusted odds ratio 1.7; 95% CI 1.19–2.42). Conclusion Thrombocytopenia occurred in 43% of critically ill patients and was associated with worse outcomes including increased mortality. Platelet transfusions were given to 23% of patients with thrombocytopenia and most were prophylactic.publishedVersio