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Azimuthal anisotropy measurement of (multi-)strange hadrons in Au+Au collisions at √sNN = 54.4 GeV
(2023)
Azimuthal anisotropy of produced particles is one of the most important observables used to access the collective properties of the expanding medium created in relativistic heavy-ion collisions. In this paper, we present second (v2) and third (v3) order azimuthal anisotropies of K0S, ϕ, Λ, Ξ and Ω at mid-rapidity (|y|<1) in Au+Au collisions at sNN−−−√ = 54.4 GeV measured by the STAR detector. The v2 and v3 are measured as a function of transverse momentum and centrality. Their energy dependence is also studied. v3 is found to be more sensitive to the change in the center-of-mass energy than v2. Scaling by constituent quark number is found to hold for v2 within 10%. This observation could be evidence for the development of partonic collectivity in 54.4 GeV Au+Au collisions. Differences in v2 and v3 between baryons and anti-baryons are presented, and ratios of v3/v3/22 are studied and motivated by hydrodynamical calculations. The ratio of v2 of ϕ mesons to that of anti-protons (v2(ϕ)/v2(p¯)) shows centrality dependence at low transverse momentum, presumably resulting from the larger effects from hadronic interactions on anti-proton v2.
Elliptic flow of heavy-flavor decay electrons in Au+Au collisions at √sNN = 27 and 54.4 GeV at RHIC
(2023)
We report on new measurements of elliptic flow (v2) of electrons from heavy-flavor hadron decays at mid-rapidity (|y|<0.8) in Au+Au collisions at sNN−−−√ = 27 and 54.4 GeV from the STAR experiment. Heavy-flavor decay electrons (eHF) in Au+Au collisions at sNN−−−√ = 54.4 GeV exhibit a non-zero v2 in the transverse momentum (pT) region of pT< 2 GeV/c with the magnitude comparable to that at sNN−−−√=200 GeV. The measured eHF v2 at 54.4 GeV is also consistent with the expectation of their parent charm hadron v2 following number-of-constituent-quark scaling as other light and strange flavor hadrons at this energy. These suggest that charm quarks gain significant collectivity through the evolution of the QCD medium and may reach local thermal equilibrium in Au+Au collisions at sNN−−−√=54.4 GeV. The measured eHF v2 in Au+Au collisions at sNN−−−√= 27 GeV is consistent with zero within large uncertainties. The energy dependence of v2 for different flavor particles (π,ϕ,D0/eHF) shows an indication of quark mass hierarchy in reaching thermalization in high-energy nuclear collisions.
Observation of directed flow of hypernuclei Λ³H and Λ⁴H in √sNN = 3 GeV Au+Au collisions at RHIC
(2023)
We report here the first observation of directed flow (v1) of the hypernuclei 3ΛH and 4ΛH in mid-central Au+Au collisions at sNN−−−√ = 3 GeV at RHIC. These data are taken as part of the beam energy scan program carried out by the STAR experiment. From 165 × 106 events in 5%-40% centrality, about 8400 3ΛH and 5200 4ΛH candidates are reconstructed through two- and three-body decay channels. We observe that these hypernuclei exhibit significant directed flow. Comparing to that of light nuclei, it is found that the midrapidity v1 slopes of 3ΛH and 4ΛH follow baryon number scaling, implying that the coalescence is the dominant mechanism for these hypernuclei production in such collisions.
Die Digitalisierung weiter Teile der Lebenswelt ist vor allem mit der Verbreitung und extensiven Nutzung des Smartphones verknüpft. Eine Mehrzahl der älteren Menschen in Deutschland nutzt Smartphones selbstverständlich im Alltag. Die vorliegende Studie adressiert erstens wie stark sich das Smartphone bereits in den Alltag älterer Menschen als vergleichsweise neue Technologie eingeschrieben hat. Im Mittelpunkt steht dabei, welche Funktionen genutzt werden, wie oft und wann zum Smartphone gegriffen wird und welche Gemeinsamkeiten und Unterschiede in der Nutzung identifizierbar sind. Darüber hinaus wird zweitens der Zusammenhang zwischen alltäglicher Smartphonenutzung, Medienkompetenz und technikbezogenen Einstellungen in den Blick genommen. Drittens geht die Studie der Frage nach inwiefern die Smartphonenutzung mit zentralen Variablen der Lebensqualität im Alter, der sozialer Eingebundenheit sowie dem subjektiven Wohlbefinden assoziiert ist. Die vorliegende Arbeit ist eine quantitativ empirische Studie, die einem mikrolängsschnittlichem Design folgt. Zur Beantwortung der Forschungsfragen wurden objektive Nutzungsdaten, Daten aus einem ambulanten Assessment sowie Daten eines querschnittlichen Fragebogens kombiniert. Die Ergebnisse zeigen, dass die Befragten älteren Menschen im Hinblick auf Nutzungsdauer, -intensität als auch inhaltlicher Vielfalt hohe inter- als auch intraindividuelle Unterschiede aufwiesen. Gemeinsamkeiten der Nutzung waren die Kommunikation oder Alltagsorganisation. Das Smartphone wurde aber auch zum Spielen oder für gesundheitsbezogene Handlungen genutzt. Gleichzeitig ging eine zeitlich intensive auch mit einer inhaltlich breit gefächerten Nutzung einher. Die Unterschiede in der Nutzung konnten primär durch technikbezogene Einstellungen und deklarative Wissensbestände zu Computer und Smartphone erklärt werden. Intensivnutzer wiesen positivere Einstellungen gegenüber Technik auf und verfügten über höhere Wissensbestände. Trotz intensiver Nutzung des Smartphones zur Kommunikation zeigte sich kein klarer Zusammenhang mit sozialer Eingebundenheit und subjektivem Wohlbefinden. Vielmehr konnte in diesem Kontext die wahrgenommene Qualität der erlebten sozialen Beziehungen als zentraler Prädiktor identifiziert werden. Zusammengenommen zeigte sich eine tiefe Integration des Smartphones in den Alltag älterer Smartphonenutzer.
A decisive experimental test of the Chiral Magnetic Effect (CME) is considered one of the major scientific goals at the Relativistic Heavy-Ion Collider (RHIC) towards understanding the nontrivial topological fluctuations of the Quantum Chromodynamics vacuum. In heavy-ion collisions, the CME is expected to result in a charge separation phenomenon across the reaction plane, whose strength could be strongly energy dependent. The previous CME searches have been focused on top RHIC energy collisions. In this Letter, we present a low energy search for the CME in Au+Au collisions at sNN−−−√=27 GeV. We measure elliptic flow scaled charge-dependent correlators relative to the event planes that are defined at both mid-rapidity |η|<1.0 and at forward rapidity 2.1<|η|<5.1. We compare the results based on the directed flow plane (Ψ1) at forward rapidity and the elliptic flow plane (Ψ2) at both central and forward rapidity. The CME scenario is expected to result in a larger correlation relative to Ψ1 than to Ψ2, while a flow driven background scenario would lead to a consistent result for both event planes. In 10-50\% centrality, results using three different event planes are found to be consistent within experimental uncertainties, suggesting a flow driven background scenario dominating the measurement. We obtain an upper limit on the deviation from a flow driven background scenario at the 95\% confidence level. This work opens up a possible road map towards future CME search with the high statistics data from the RHIC Beam Energy Scan Phase-II.
A decisive experimental test of the Chiral Magnetic Effect (CME) is considered one of the major scientific goals at the Relativistic Heavy-Ion Collider (RHIC) towards understanding the nontrivial topological fluctuations of the Quantum Chromodynamics vacuum. In heavy-ion collisions, the CME is expected to result in a charge separation phenomenon across the reaction plane, whose strength could be strongly energy dependent. The previous CME searches have been focused on top RHIC energy collisions. In this Letter, we present a low energy search for the CME in Au+Au collisions at sNN−−−√=27 GeV. We measure elliptic flow scaled charge-dependent correlators relative to the event planes that are defined at both mid-rapidity |η|<1.0 and at forward rapidity 2.1<|η|<5.1. We compare the results based on the directed flow plane (Ψ1) at forward rapidity and the elliptic flow plane (Ψ2) at both central and forward rapidity. The CME scenario is expected to result in a larger correlation relative to Ψ1 than to Ψ2, while a flow driven background scenario would lead to a consistent result for both event planes. In 10-50\% centrality, results using three different event planes are found to be consistent within experimental uncertainties, suggesting a flow driven background scenario dominating the measurement. We obtain an upper limit on the deviation from a flow driven background scenario at the 95\% confidence level. This work opens up a possible road map towards future CME search with the high statistics data from the RHIC Beam Energy Scan Phase-II.
Notwithstanding decades of progress since Yukawa first developed a description of the force between nucleons in terms of meson exchange, a full understanding of the strong interaction remains a major challenge in modern science. One remaining difficulty arises from the non-perturbative nature of the strong force, which leads to the phenomenon of quark confinement at distances on the order of the size of the proton. Here we show that in relativistic heavy-ion collisions, where quarks and gluons are set free over an extended volume, two species of produced vector (spin-1) mesons, namely ϕ and K∗0, emerge with a surprising pattern of global spin alignment. In particular, the global spin alignment for ϕ is unexpectedly large, while that for K∗0 is consistent with zero. The observed spin-alignment pattern and magnitude for the ϕ cannot be explained by conventional mechanisms, while a model with a connection to strong force fields, i.e. an effective proxy description within the Standard Model and Quantum Chromodynamics, accommodates the current data. This connection, if fully established, will open a potential new avenue for studying the behaviour of strong force fields.
We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C5, C6) and factorial cumulants (κ5, κ6) of net-proton and proton distributions, from sNN−−−−√=3−200 GeV Au+Au collisions at RHIC. The net-proton cumulant ratios generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at sNN−−−−√ = 3 GeV. C6/C2 for 0-40\% centrality collisions is increasingly negative with decreasing sNN−−−−√, while it is positive for the lowest sNN−−−−√ studied. These observed negative signs are consistent with QCD calculations (at baryon chemical potential, μB≤ 110 MeV) that include a crossover quark-hadron transition. In addition, for sNN−−−−√≥ 11.5 GeV, the measured proton κn, within uncertainties, does not support the two-component shape of proton distributions that would be expected from a first-order phase transition. Taken in combination, the hyper-order proton number fluctuations suggest that the structure of QCD matter at high baryon density, μB∼750 MeV (sNN−−−−√ = 3 GeV) is starkly different from those at vanishing μB∼20MeV (sNN−−−−√ = 200 GeV and higher).
We report on measurements of sequential Υ suppression in Au+Au collisions at sNN−−−√ = 200 GeV with the STAR detector at the Relativistic Heavy Ion Collider (RHIC) through both the dielectron and dimuon decay channels. In the 0-60% centrality class, the nuclear modification factors (RAA), which quantify the level of yield suppression in heavy-ion collisions compared to p+p collisions, for Υ(1S) and Υ(2S) are 0.40±0.03 (stat.)±0.03 (sys.)±0.09 (norm.) and 0.26±0.08 (stat.)±0.02 (sys.)±0.06 (norm.), respectively, while the upper limit of the Υ(3S) RAA is 0.17 at a 95% confidence level. This provides experimental evidence that the Υ(3S) is significantly more suppressed than the Υ(1S) at RHIC. The level of suppression for Υ(1S) is comparable to that observed at the much higher collision energy at the Large Hadron Collider. These results point to the creation of a medium at RHIC whose temperature is sufficiently high to strongly suppress excited Υ states.
The longitudinal and transverse spin transfers to Λ (Λ¯¯¯¯) hyperons in polarized proton-proton collisions are expected to be sensitive to the helicity and transversity distributions, respectively, of (anti-)strange quarks in the proton, and to the corresponding polarized fragmentation functions. We report improved measurements of the longitudinal spin transfer coefficient, DLL, and the transverse spin transfer coefficient, DTT, to Λ and Λ¯¯¯¯ in polarized proton-proton collisions at s√ = 200 GeV by the STAR experiment at RHIC. The data set includes longitudinally polarized proton-proton collisions with an integrated luminosity of 52 pb−1, and transversely polarized proton-proton collisions with a similar integrated luminosity. Both data sets have about twice the statistics of previous results and cover a kinematic range of |ηΛ(Λ¯¯¯¯)| < 1.2 and transverse momentum pT,Λ(Λ¯¯¯¯) up to 8 GeV/c. We also report the first measurements of the hyperon spin transfer coefficients DLL and DTT as a function of the fractional jet momentum z carried by the hyperon, which can provide more direct constraints on the polarized fragmentation functions.
Partons traversing the strongly interacting medium produced in heavy-ion collisions are expected to lose energy depending on their color charge and mass. We measure the nuclear modification factors for charm- and bottom-decay electrons, defined as the ratio of yields, scaled by the number of binary nucleon-nucleon collisions, in sNN−−−√ = 200 GeV Au+Au collisions to p+p collisions (RAA), or in central to peripheral Au+Au collisions (RCP). We find the bottom-decay electron RAA and RCP to be significantly higher than that of charm-decay electrons. Model calculations including mass-dependent parton energy loss in a strongly coupled medium are consistent with the measured data. These observations provide clear evidence of mass ordering of charm and bottom quark energy loss when traversing through the strongly coupled medium created in heavy-ion collisions.
Partons traversing the strongly interacting medium produced in heavy-ion collisions are expected to lose energy depending on their color charge and mass. We measure the nuclear modification factors for charm- and bottom-decay electrons, defined as the ratio of yields, scaled by the number of binary nucleon-nucleon collisions, in sNN−−−√ = 200 GeV Au+Au collisions to p+p collisions (RAA), or in central to peripheral Au+Au collisions (RCP). We find the bottom-decay electron RAA and RCP to be significantly higher than that of charm-decay electrons. Model calculations including mass-dependent parton energy loss in a strongly coupled medium are consistent with the measured data. These observations provide clear evidence of mass ordering of charm and bottom quark energy loss when traversing through the strongly coupled medium created in heavy-ion collisions.
Elliptic flow of heavy-flavor decay electrons in Au+Au collisions at √sNN = 27 and 54.4 GeV at RHIC
(2023)
We report on new measurements of elliptic flow (v2) of electrons from heavy-flavor hadron decays at mid-rapidity (|y|<0.8) in Au+Au collisions at sNN−−−√ = 27 and 54.4 GeV from the STAR experiment. Heavy-flavor decay electrons (eHF) in Au+Au collisions at sNN−−−√ = 54.4 GeV exhibit a non-zero v2 in the transverse momentum (pT) region of pT< 2 GeV/c with the magnitude comparable to that at sNN−−−√=200 GeV. The measured eHF v2 at 54.4 GeV is also consistent with the expectation of their parent charm hadron v2 following number-of-constituent-quark scaling as other light and strange flavor hadrons at this energy. These suggest that charm quarks gain significant collectivity through the evolution of the QCD medium and may reach local thermal equilibrium in Au+Au collisions at sNN−−−√=54.4 GeV. The measured eHF v2 in Au+Au collisions at sNN−−−√= 27 GeV is consistent with zero within large uncertainties. The energy dependence of v2 for different flavor particles (π,ϕ,D0/eHF) shows an indication of quark mass hierarchy in reaching thermalization in high-energy nuclear collisions.
We report a new measurement of the production of electrons from open heavy-flavor hadron decays (HFEs) at mid-rapidity (|y| < 0.7) in Au+Au collisions at √sNN = 200 GeV. Invariant yields of HFEs are measured for the transverse momentum range of 3.5 < pT < 9 GeV/c in various configurations of the collision geometry. The HFE yields in head-on Au+Au collisions are suppressed by approximately a factor of 2 compared to that in p + p collisions scaled by the average number of binary collisions, indicating strong interactions between heavy quarks and the hot and dense medium created in heavy-ion collisions. Comparison of these results with models provides additional tests of theoretical calculations of heavy quark energy loss in the quark-gluon plasma.
Density fluctuations near the QCD critical point can be probed via an intermittency analysis in relativistic heavy-ion collisions. We report the first measurement of intermittency in Au+Au collisions at sNN−−−√ = 7.7-200 GeV measured by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The scaled factorial moments of identified charged hadrons are analyzed at mid-rapidity and within the transverse momentum phase space. We observe a power-law behavior of scaled factorial moments in Au+Au collisions and a decrease in the extracted scaling exponent (ν) from peripheral to central collisions. The ν is consistent with a constant for different collisions energies in the mid-central (10-40\%) collisions. Moreover, the ν in the 0-5\% most central Au+Au collisions exhibits a non-monotonic energy dependence that reaches a possible minimum around sNN−−−√ = 27 GeV. The physics implications on the QCD phase structure are discussed.
The linear and mode-coupled contributions to higher-order anisotropic flow are presented for Au+Au collisions at sNN−−−√ = 27, 39, 54.4, and 200 GeV and compared to similar measurements for Pb+Pb collisions at the Large Hadron Collider (LHC). The coefficients and the flow harmonics' correlations, which characterize the linear and mode-coupled response to the lower-order anisotropies, indicate a beam energy dependence consistent with an influence from the specific shear viscosity (η/s). In contrast, the dimensionless coefficients, mode-coupled response coefficients, and normalized symmetric cumulants are approximately beam-energy independent, consistent with a significant role from initial-state effects. These measurements could provide unique supplemental constraints to (i) distinguish between different initial-state models and (ii) delineate the temperature (T) and baryon chemical potential (μB) dependence of the specific shear viscosity ηs(T,μB).
The main focus of this thesis is the application of the nonperturbative Functional Renormalization Group (FRG) to the study of low-energies effective models for Quantum Chromodynamics (QCD). The study of effective field theories and models is crucial for our understanding of physics, especially when we deal with fundamental interaction theories like QCD. In particular, the ultimate goal is the understanding of the critical properties of these models in such a way that we can have an insight on the actual critical phenomena of QCD, with a special focus on its chiral phase transition. The choice of the FRG method derives from the fact that it belongs to the class of functional non-perturbative methods and has also the advantage of linking physics at different energy scales. These features make FRG perfectly compatible with the task of studying non-perturbative phenomena and in particular phase transitions, like the ones expected for strongly interacting matter. However, the functional nature of the FRG approach and of the Wetterich equation has a consequence that its exact resolution is hardly possible, and an ansatz for the effective action is generally needed. In this work we choose to adopt the local-potential approximation (LPA), which prescribes to stop at zeroth order in the expansion in derivative operators of the quantum effective action, including only the quantum effective potential. In this work we exploited the key observation that the FRG flow equation can be cast, for specific models and truncation schemes, in the form of an advection-diffusion, possibly with a source term. This type of equation belongs to the class of problems faced in the context of viscous hydrodynamics. Therefore, an innovative approach to the solution of the FRG flow equation consists in the choice of a method developed specifically for the resolution of this class of hydrodynamic equations. In particular, the Kurganov-Tadmor finite-volume scheme is adopted. Throughout this work we apply this scheme to the study of different physical systems, showing the reliability and the flexibility of this approach.
In the first part of the thesis, we discuss the well-known O(N) model, using the hydrodynamic formulation to solve the FRG flow equation in the LPA truncation. We focus on the study of the critical behaviour of the system and calculate the corresponding critical exponents. Particular attention is given to the error estimation in the extraction of critical exponents, which is a needed and not widely explored aspect. The results are well compatible with others in the literature, obtained with different perturbative and nonperturbative methods, which validates the procedure. In the second part of the thesis, we introduce the quark-meson model as a low-energy effective model for QCD, with a specific focus on its chiral symmetry-breaking pattern and the subsequent dynamical quark-mass generation. The LPA flow equation is of the advection-diffusion type, with an extra source contribution which is due to the inclusion of fermionic degrees of freedom. We thus adopt the developed numerical techniques to derive the phase diagram of the model, which is in agreement with the one obtained with other techniques in the literature.
We also follow another possible way for the study of the critical properties of the quark-meson model: the so-called thermodynamic geometry. This approach is based on the interpretation of the parameter space of the system as a differential manifold. One can then obtain relevant information about the phase transitions from the Ricci scalar. We studied the chiral crossover investigating the behavior of the Ricci scalar up to the critical point, featuring a peaking behavior in the presence of the crossover. We then repeated this analysis in the chiral limit, where the phase transition is expected to be of second order. Via this geometric technique it is possible to have a different view on the chiral phase transition of QCD. This is the case since this approach is based on the calculation of quantities which are influenced by higher-order momenta of the thermodynamic potential, thus allowing for a more comprehensive analysis of the phase transition.
Finally, we exploit the numerical advancement to face the issue of the regulator choice in the FRG calculations. This is one of the most delicate issues which arise when using approximations to solve the FRG flow equation and deserves extensive investigation. In particular, we performed a vacuum parameter study and used the RG consistency requirement to determine the impact of the choice of the regulator on the physical observables and on the phase diagram of the model. Via this study we develop a systematic method to comparison the results obtained via different regulators. We show the importance of the choice of an appropriate UV cutoff in the determination of UV-independent IR observables and, consequently, the impact on the latter that the truncation of the effective average action and the choice of the regulator have.
A decisive experimental test of the Chiral Magnetic Effect (CME) is considered one of the major scientific goals at the Relativistic Heavy-Ion Collider (RHIC) towards understanding the nontrivial topological fluctuations of the Quantum Chromodynamics vacuum. In heavy-ion collisions, the CME is expected to result in a charge separation phenomenon across the reaction plane, whose strength could be strongly energy dependent. The previous CME searches have been focused on top RHIC energy collisions. In this Letter, we present a low energy search for the CME in Au+Au collisions at sNN−−−√=27 GeV. We measure elliptic flow scaled charge-dependent correlators relative to the event planes that are defined at both mid-rapidity |η|<1.0 and at forward rapidity 2.1<|η|<5.1. We compare the results based on the directed flow plane (Ψ1) at forward rapidity and the elliptic flow plane (Ψ2) at both central and forward rapidity. The CME scenario is expected to result in a larger correlation relative to Ψ1 than to Ψ2, while a flow driven background scenario would lead to a consistent result for both event planes. In 10-50\% centrality, results using three different event planes are found to be consistent within experimental uncertainties, suggesting a flow driven background scenario dominating the measurement. We obtain an upper limit on the deviation from a flow driven background scenario at the 95\% confidence level. This work opens up a possible road map towards future CME search with the high statistics data from the RHIC Beam Energy Scan Phase-II.
Autism Spectrum Disorder (ASD) is a neurodevelopmental condition with an onset in early development. ASD has varying degrees of severity and thus affects people differently throughout their lives. Early diagnosis of ASD is essential to provide children with individually-tailored support.8 Eye-tracking may contribute to an earlier diagnosis: Several studies showed differences in eye movements between people with autism spectrum disorder (ASD) and typically developing controls (TD). Different eye movements may contribute to different visual perception that perpetuates to problems in attention, communication and social interaction.
Eye movements are divided into: (1) Fixations (2) Saccades (fast and short eye movements) and (3) Smooth Pursuit Eye Movements (SPEM). SPEM follow the target in a continuous manner. The latter are the subject of the present thesis. SPEM consist of two phases: the open loop phase (= phase of initiation, first 50- 100ms) and the closed loop phase (= phase of maintenance, after about 100ms). SPEM are usually measured by a gain index. It is defined as the ratio of smooth pursuit velocity and visual target velocity and ideally equals to 1.2
In young children, corneal-reflection (CR) eye-tracking is usually applied to quantify eye movement. It allows precise measurements without the use of potentially intrusive devices.
Studies in ASD reported deficits in open loop and closed loop pursuit in children and adults with a mean age of 19.32 (TD) and 20.04 (ASD) years. However, SPEM in preschoolers with ASD remain understudied, although this developmental phase is crucial to the development of non-social and social attentional abilities.
In the present study 66 toddlers and preschoolers (18 to 72 months; ASD: n = 33, TD: n = 33) with matched cognitive abilities and sex were assessed. The main objective was to compare the gain index (Smooth Pursuit Gain = SPG). SPEM were compared between groups with gain index as a dependent measure. We hypothesized that participants with ASD show lower average gain compared to the control group.
We could show a significant group influence on the gain when considering interactions between target velocity and group (p = 0.041). The TD group showed a greater dependence on the increasing object speed than the ASD group with a trend of -0.30 ± 0.11 in the TD group and a trend of -0.13 ± 0.12 in the ASD group. Across groups, the gain decreased with increasing target velocity and dropped faster in vertical than in horizontal trials. Additionally, participants showed a lower SPG in vertical sequences than in horizontal sequences. This supports the general validity of the measure.
Toddlers and preschoolers represent a group that has been subject of little research to date. In addition, there has been only a limited number of studies analyzing SPEM in ASD. To check for a possible group difference without interactions a study with a larger sample size at fixed target velocity and target direction should follow.
Oxytocin, welches primär als Hormon bekannt ist, beeinflusst als Neuromodulator viele kognitive Prozesse, die an sozialem Verhalten, wie Sprache, beteiligt sind. Einerseits verändert es akustische Merkmale von gesprochener Sprache, andererseits erleichtert es auf perzeptueller Ebene die Emotionserkennung in der Sprachwahrnehmung und Körpersprache. Bislang war nicht bekannt, wie Oxytocin Hirnaktivität während des Sprechens verändert. Wir hypothetisierten, dass dieser Neuromodulator ähnlich wie Dopamin kortiko-basale Schaltkreise bahnen könnte.
Wir führten eine doppelt-verblindete Verhaltens- und funktionelle Kernspintomographiestudie durch, in der 52 gesunde Probanden an zwei getrennten Untersuchungsterminen entweder intranasales Oxytocin oder ein Placebo erhielten. Die Teilnehmer lasen Sätze außerhalb des Kernspintomographen und im Scanner leise oder laut mit entweder neutraler oder fröhlicher Intonation vor.
Die Verabreichung von Oxytocin erhöhte den zweiten Formanten der produzierten Vokale. Höhere Frequenzen dieses akustischen Parameters wurden zuvor mit einer positiven Valenz gesprochener Sprache in Verbindung gebracht; jedoch konnten unabhängige Beurteiler*innen die akustischen Unterschiede in unserem experimentellen Setting nicht konsistent unterscheiden.
Als neuronales Korrelat verstärkte Oxytocin die präparatorische subkortikale Gehirnaktivität im ventralen Pallidum und Striatum. Auch kortikal erhöhte Oxytocin präparatorische Gehirnaktivität in Regionen des dorsalen wie auch des ventralen Sprachverarbeitungsstroms, in sensomotorischen Kortizes und limbischen sowie exekutiven Regionen. In einigen dieser Regionen modulierte der genetische Oxytocin- Rezeptor-Polymorphismus rs53576 die durch die Oxytocin-Verabreichung verursachte Gehirnaktivität. Ähnlich wie Dopamin modulierte Oxytocin außerdem kortiko-basale Schaltkreise, die an der Generierung von fröhlicher Prosodie beteiligt sind. Während der Vorbereitung von Sprache erhöhte der Neuromodulator die funktionelle Konnektivität zwischen dem ventralem Pallidum und dem dorsolateralen präfrontalen Kortex mit einem spiegelbildlichen Profil während des eigentlichen Sprechens, einen Effekt den wir als „gating“ (Bahnung) interpretierten.
Unsere Ergebnisse legen nahe, dass mehrere neuronale Prozesse, die der Sprachproduktion zugrundeliegen, durch Oxytocin moduliert werden. Das Muster ähnelt hierbei dem anderer Neuromodulatoren wie Dopamin. Die vorliegende Arbeit charakterisiert somit erstmals Oxytocineffekte auf die mit Sprachproduktion assoziierte Hirnaktivität und funktionelle Konnektivität.
Measurements of vertical velocity from vertically pointing Doppler lidars are used to derive the profiles of normalized vertical velocity variance. Observations were taken during the FESSTVaL (Field Experiment on Submesoscale Spatio-Temporal Variability in Lindenberg) campaign during the warm seasons of 2020 and 2021. Normalized by the square of the convective velocity scale, the average vertical velocity variance profile follows the universal profile of Lenschow et al. (1980). However, daily profiles still show a high day-to-day variability. We found that moisture transport and the content of moisture in the boundary layer could explain the remaining variability of the normalized vertical velocity variance. The magnitude of the normalized vertical velocity variance is highest on clear-sky days and decreases as the absolute humidity increases and surface latent heat flux decreases on cloud-topped days. This suggests that moisture content and moisture transport are limiting factors for the intensity of turbulence in the convective boundary layer. We also found that the intensity of turbulence decreases with an increase in the boundary layer cloud fraction during FESSTVaL, while the latent heating in the cloud layer was not a relevant source of turbulence in this case. We conclude that a new vertical velocity scale has to be defined that would take into account the moist processes in the convective boundary layer.
The elliptic (v2) and triangular (v3) azimuthal anisotropy coefficients in central 3He+Au, d+Au, and p+Au collisions at sNN−−−√ = 200 GeV are measured as a function of transverse momentum (pT) at mid-rapidity (|η|<0.9), via the azimuthal angular correlation between two particles both at |η|<0.9. While the v2(pT) values depend on the colliding systems, the v3(pT) values are system-independent within the uncertainties, suggesting an influence on eccentricity from sub-nucleonic fluctuations in these small-sized systems. These results also provide stringent constraints for the hydrodynamic modeling of these systems.
The linear and mode-coupled contributions to higher-order anisotropic flow are presented for Au+Au collisions at √sN N = 27, 39, 54.4, and 200 GeV and compared to similar measurements for Pb+Pb collisions at the Large Hadron Collider (LHC). The coefficients and the flow harmonics’ correlations, which characterize the linear and mode-coupled response to the lower-order anisotropies, indicate a beam energy dependence consistent with an influence from the specific shear viscosity (η/s). In contrast, the dimensionless coefficients, mode-coupled response coefficients, and normalized symmetric cumulants are approximately beam-energy independent, consistent with a significant role from initialstate effects. These measurements could provide unique supplemental constraints to (i) distinguish between different initial-state models and (ii) delineate the temperature (T ) and baryon chemical potential (μB ) dependence of the specific shear viscosity η s (T ,μB ).
Density fluctuations near the QCD critical point can be probed via an intermittency analysis in relativistic heavy-ion collisions. We report the first measurement of intermittency in Au+Au collisions at √sNN = 7.7-200 GeV measured by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The scaled factorial moments of identified charged hadrons are analyzed at mid-rapidity and within the transverse momentum phase space. We observe a power-law behavior of scaled factorial moments in Au+Au collisions and a decrease in the extracted scaling exponent (ν) from peripheral to central collisions. The ν is consistent with a constant for different collisions energies in the mid-central (10-40%) collisions. Moreover, the ν in the 0-5% most central Au+Au collisions exhibits a non-monotonic energy dependence that reaches a minimum around √sNN = 27 GeV. The physics implications on the QCD phase structure are discussed.
The sympathetic nervous system (SNS) is a major regulatory mediator connecting the brain and the immune system that influences accordingly inflammatory processes within the entire body. In the periphery, the SNS exerts its effects mainly via its neurotransmitters norepinephrine (NE) and epinephrine (E), which are released by peripheral nerve endings in lymphatic organs and other tissues. Depending on their concentration, NE and E bind to specific α- and β-adrenergic receptor subtypes and can cause both pro- and anti-inflammatory cellular responses. The co-transmitter neuropeptide Y, adenosine triphosphate, or its metabolite adenosine are also mediators of the SNS. Local pro-inflammatory processes due to injury or pathogens lead to an activation of the SNS, which in turn induces several immunoregulatory mechanisms with either pro- or anti-inflammatory effects depending on neurotransmitter concentration or pathological context. In chronic inflammatory diseases, the activity of the SNS is persistently elevated and can trigger detrimental pathological processes. Recently, the sympathetic contribution to mild chronic inflammatory diseases like osteoarthritis (OA) has attracted growing interest. OA is a whole-joint disease and is characterized by mild chronic inflammation in the joint. In this narrative article, we summarize the underlying mechanisms behind the sympathetic influence on inflammation during OA pathogenesis. In addition, OA comorbidities also accompanied by mild chronic inflammation, such as hypertension, obesity, diabetes, and depression, will be reviewed. Finally, the potential of SNS-based therapeutic options for the treatment of OA will be discussed.
Die akute Nierenschädigung ist ein häufiges klinisches Erscheinungsbild, das trotz der heutigen Erkenntnisse über pathophysiologische Abläufe in der Niere mit einer erhöhten Morbidität und Mortalität assoziiert ist. Die eigene Fähigkeit der Niere zur Regeneration stellt ein Potenzial dar, das durch die Unterstützung pro-regenerativer Faktoren das Patientenüberleben verbessern kann. Das Wissen, dass die akute Nierenschädigung ein reversibles Ereignis darstellt, bestärkt den Einsatz der Forschung pro-regenerative Einflussfaktoren zu bestimmen, deren Zusammenhang darzustellen und eine mögliche Strategie zur innovativen Therapie zu entwickeln. Um eine akute Nierenschädigung darzustellen und anschließend auf regenerative Prozesse zu untersuchen, wurde ein Cisplatin-induziertes in vitro-Schädigungsmodell an primären Tubulusepithelzellen (mTEZ) aus Wildtyp Mäusen etabliert. Nach Isolation und Kultivierung primärer mTEZ erfolgte die Schädigung mit Cisplatin, die anhand eines Zytotoxizitätsnachweises quantifiziert wurde. Makrophagen zeichnen sich durch ihre funktionale Vielfalt in physiologischen als auch pathophysiologischen Abläufen aus. Ihre Plastizität ermöglicht es ihnen, sich entsprechend des umgebenden Milieus mit ihrem Phänotyp anzupassen und folglich in Form eines pro-regenerativen Makrophagen Proliferation und Reparaturprozesse zu unterstützen. Für die Untersuchung einer Makrophagen-vermittelten, pro-regenerativen Wirkung auf geschädigte mTEZ wurden primäre Zellen aus dem Knochenmark von Mäusen isoliert und zu Makrophagen differenziert. Zur Ausprägung eines pro-regenerativen Makrophagen Phänotyps erfolgte die Stimulation der kultivierten Makrophagen durch Inkubation mit Interleukin-10 (IL-10) und die Herstellung eines konditionierten Mediums (KM). Lipocalin-2 (Lcn-2) ist bekannt als früher Biomarker im Rahmen der akuten Nierenschädigung, aber zeichnet sich zusätzlich durch seine pro-proliferative Wirkung und regenerative Funktion aus. Lcn-2 ist ein Protein, das Eisen mit hoher Affinität bindet und in Makrophagen als alternativer Eisen-Transportmechanismus dient. In der vorliegenden Untersuchung stellte sich bei Stimulation mit IL-10 ein pro-regenerativer Makrophagen Phänotyp dar, der sich durch eine erhöhte Eisenfreisetzung und dem erhöhten Nachweis von Eisen-beladenen Lcn-2 im KM auszeichnete (holo-Lcn-2). Um den Zusammenhang von Lcn-2 aus IL-10-stimulierten Makrophagen und die regenerativen Eigenschaften auf mTEZ zu untersuchen, wurde ein Versuchsaufbau etabliert, indem mTEZ mit Cisplatin geschädigt und anschließend ein KM von IL-10-stimulierten Wildtyp (WT) oder Lcn-2 knockout Makrophagen hinzugefügt wurde. Zusätzlich wurde ein rekombinantes holo-Lcn-2 hergestellt, das als Zugabe zu KM von Lcn-2 knockout Makrophagen der Wiederherstellung und der Untersuchung eines Lcn-2-abhängigen Mechanismus diente. Als Merkmal einer Zellregeneration wurden die epitheliale Integrität und die Reorganisation des Zytoskeletts bestimmt. Ergänzend konnte mit Hilfe der Expression von Proliferationsmarkern sowie einer Echtzeitmessung der Proliferationsrate eine zunehmende Proliferation geschädigter mTEZ nach Zugabe von KM aus Makrophagen in Abhängigkeit von Lcn-2 bewiesen werden. Anschließend wurde eine Analyse des Eisengehalts im Zelllysat von mTEZ durchgeführt. Hierbei konnte ein signifikanter Anstieg des Eisengehaltes in mTEZ nach Zugabe von KM aus WT Makrophagen als auch durch Ergänzung von rekombinanten holo-Lcn-2 zu KM aus Lcn-2 knockout Makrophagen nachgewiesen werden. In der Korrelation zwischen Eisenmenge im Zelllysat der mTEZ und der Proliferationsrate ergab sich eine zunehmende Proliferation mit Anstieg des Eisengehaltes der Zelle. Zusammenfassend ergaben unsere Untersuchungen, dass KM aus pro-regenerativen Makrophagen die Überlebensfähigkeit von mTEZ nach Cisplatin-Schädigung steigert. Es zeigte sich auch eine durch Lcn-2 geförderte epitheliale Integrität sowie ein pro-proliferativer Effekt. Die regenerativen Effekte an mTEZ wurden durch Lcn-2 aus KM von IL-10-stimulierten Makrophagen über seine Eisen-bindende Funktion vermittelt. Über die Ausschüttung von Lcn-2 vermitteln pro-regenerative Makrophagen vermutlich die Zell-Regeneration von mTEZ, indem Lcn-2 toxisches Eisen von geschädigten und apoptotischen Zellen aus der Umgebung bindet, es Zielzellen als holo-Lcn-2 zur Verfügung stellt und hierdurch die Proliferation induziert.
The attention on the protein PURA has increased recently following the discovery of the rare PURA Syndrome. This neurodevelopmental disorder is caused by de novo mutations in the PURA gene. Notably, our collaborators could show that the protein PURA can bind DNA and RNA in vitro. As a result, I was motivated to explore PURA's cellular RNAbinding activity. Furthermore, I inquired on the connection of PURA-RNA binding to the cellular effect of a reduction of functional PURA as present in PURA Syndrome patients.
To investigate the binding of PURA and the impact of PURA de ciency on cellular RNA and protein expression, I performed an integrative computational analysis of multimodal data from complementary high-throughput experiments. An essential component was the examination of UV Crosslinking and immunoprecipitation (CLIP) experiments, which can query the global RNA-binding behaviour of a given protein in a cellular context. As the processing and analysis of CLIP data are rather complex, I introduce an automated command line tool for the processing of CLIP data named racoon_clip as part of this dissertation. Therefore, this dissertation comprises two major segments. Firstly, I describe the implementation and usage of racoon clip for CLIP data analysis. Secondly, I discuss my research on the protein PURA, demonstrating its global RNA-binding properties, the effects of PURA depletion and its association with neuronal functions and P-bodies, among others.
racoon_clip is a command line application that I have developed for processing of individualnucleotide resolution CLIP (iCLIP) and enhanced CLIP (eCLIP) experiments - two of the most commonly used types of CLIP experiments - in a comparable and user-friendly way.
For this, I built racoon_clip as an automated work how that encompasses all CLIP processing steps from raw data to single-nucleotide resolution crosslink events. racoon_clip is available as a command line tool that users can run with a single command. The work how is implemented with Snakemake work how management providing computational advantage tages including parallelisation, scalability and portability of the work how. The main task of racoon_clip is to extract single-nucleotide crosslink events from iCLIP, iCLIP2, eCLIP and similar data types. To strike a balance between being highly customisable and easy to use, racoon_clip supplies pre-set options for the most common types of experiments.
Additionally, it is possible for users to create a custom setup of barcode and adapter architectures, which allows them to use the software for other types of CLIP data. While accounting for the different architectures in the reads, the performed central processing steps remain the same. This leads to a high degree of comparability between the different experiment types, which I demonstrate in the exemplary processing of U2AF2 iCLIP and eCLIP data. Taken together, I am confident that racoon_clip will be beneficial to numerous researchers interested in RNA-Protein interactions as it offers easily accessible processing for CLIP data and enhances the comparability of multiple CLIP datasets across di erent experiment types.
In the second part of this dissertation, I focus on the cellular function of the RNAbinding protein PURA. Through in-depth computational analysis of one iCLIP data set of endogenous PURA and two iCLIP data sets of overexpressed PURA in HeLa cells, I establish that PURA is a global RNA-binding protein. It preferentially binds RNAs in either the coding sequence (CDS) or the 3' untranslated region (3'UTR) of mature protein-coding transcripts by recognising a Purine-rich degenerated sequence motif. Even though overexpression of PURA results in less specific binding behaviour, the same overall binding patterns as from endogenous PURA persist. Overall characteristics of PURA binding remain similar in three distinct PURA iCLIP data sets with and without PURA overexpression.
To learn about the molecular consequences of a depletion of functional PURA in a cellular context, I used a 50% reduction of PURA in HeLa cells as a model for the heterozygous loss of PURA in PURA Syndrome and evaluated its impact on global RNA and protein expression. The results demonstrate that PURA depletion globally a ects RNA and protein expression. Additionally, I integrate PURA RNA binding with the changes in expression of RNAs and proteins in the context of PURA depletion. This reveals 234 targets of PURA that are bound by PURA and are impacted at both RNA and protein levels by the PURA protein. RNAs that are bound by PURA or change in abundance upon PURA depletion are enriched in neuronal development factors, RNA lifecycle regulators, and mitochondrial factors, among others. Consistent with a possible role of PURA in neuronal transport, there is considerable overlap between PURA bound transcripts and transcripts, that are transported to the dendritic end of neurons.
Notably, there is a link between PURA and P-bodies, as documented by the enrichment of PURA-bound RNAs in both the P-body and stress granule transcriptome. Further, PURA was found by our collaborators to be localised within P-bodies and P-body numbers were strongly reduced in cells that are depleted of PURA. This absence might be attributed to the downregulation of the proteins encoded by the PURA targets LSM14A and DDX6 as both of them were previously identified as essential for P-body formation.
Overall, the reduction of P-body numbers in PURA depletion, the neuronal function of PURA, and its association with mitochondria and RNA lifecycle regulation may indicate the cellular foundation of both PURA Syndrome and related neuronal diseases.
In summary, I present a versatile and user-friendly computational tool for the analysis of CLIP data. Subsequently, I conduct a thorough computational analysis of CLIP and other high-throughput data in the context of the RNA-binding protein PURA, which offers valuable insights into the cellular functions of PURA. These insights advance our understanding of the impact of PURA loss in PURA Syndrome and other disease contexts.
leporello #19
(2024)
Uni-Highlights Januar 2024 : Einladungen zu ausgewählten Veranstaltungen der Goethe-Universität
(2024)
Graphium chironides malayanum Eliot, 1982 was described as a taxon occurring sympatrically with G. bathycles bathycloides in Peninsular Malaysia. However, the validity of the subspecies has been questioned in a recent publication that was based on a study of DNA and morphology, implying that G. c. malayanum is a synonym of G. b. bathycloides and G. chironides is absent from the Peninsula. A re-examination of male wing morphology, genitalia and DNA shows that G. c. malayanum is a valid taxon distinguished from G. b. bathycloides by wider discal markings, a less falcate forewing, distinct differences in the arms of the harpe in the male genitalia and clearly divergent mtDNA COI genes. In the DNA analysis, G. c. malayanum formed a monophyletic clade closely related to G. chironides from China, and both were well-separated from the G. b. bathycloides clade. An examination of characters used in the previous study showed that the conclusions reached were due to misinterpretation of diagnostic characters, misidentification of specimens and the absence of G. c. malayanum among the specimens examined. When these characters were correctly interpreted, each specimen was readily assigned to the correct taxon. Diagnostic morphological characters are reclarified based on the current data.
Two new species of terrestrial isopods are described from iron ore caves in Brazil, within the Amazon biome, Circoniscus mendesi López-Orozco, Campos-Filho & Bichuette sp. nov. and C. xikrin López-Orozco, Campos-Filho & Carpio-Díaz sp. nov. (Scleropactidae). In addition, the knowledge of the distribution of Ctenorillo ferrarai Campos-Filho, Araujo & Taiti, 2014 (Armadillidae) is extended to Parauapebas, and Benthanoides tarzan Cardoso & Ferreira, 2023 to south area of the Campos Ferruginosos National Park, both in the State of Pará. Moreover, a distribution map and photographs of the species are given.
Three new species of Loxosceles Heinecken & Lowe, 1832 (Araneae, Sicariidae) from Brazilian caves
(2024)
Three new species of recluse spiders are described from Brazilian caves with both males and females. Loxosceles boqueirao Bertani & Gallão sp. nov. is found in the State of Bahia, in the Serra do Ramalho karst area, it belongs to the rufescens species group, and is closely related to L. cardosoi Bertani, von Schimonsky & Gallão, 2018 and L. carinhanha Bertani, von Schimonsky & Gallão, 2018 from the same karst area. Thus, there are now three species in the Serra do Ramalho karst area closely related, but noticeably distinct morphologically from other species of Loxosceles. Loxosceles planetaria Bertani & Gallão sp. nov. and L. bodoquena Bertani & Gallão sp. nov. are found in the State of Mato Grosso do Sul, in the Serra da Bodoquena karst area. They belong to the gaucho species group and are closely related to L. gaucho Gertsch, 1967. These are the first species of Loxosceles described from this karst area in the State of Mato Grosso do Sul. Loxosceles boqueirao sp. nov. and L. bodoquena sp. nov. bear some troglomorphisms and are, herein, proposed as troglobitic species, whereas L. planetaria sp. nov. is proposed as a troglophilic species. Brazil has now 22 described species of Loxosceles.
The remarkable sharpshooter Prodigiella silvanoi gen. et sp. nov. is described and illustrated (including the external form, color, male and female terminalia) from the Atlantic Forest of southern and southeastern Brazil (states of Paraná and Rio de Janeiro). The new genus can be distinguished from other Neotropical genera of the Cicadellini by a combination of various morphological features, including an asymmetrical aedeagus with a bifid shaft and peculiar basal and apical processes and ovipositor valvula II distinctly expanded beyond basal curvature, its dorsal margin with 35–40 teeth, and ventral margin without preapical prominence. A discussion comparing Prodigiella with superficially similar taxa of the genera Macugonalia Young, 1977, Ruppeliana Young, 1977, and Versigonalia Young, 1977 is provided. The discovery of this peculiar new genus indicates that much collecting work in the remaining parts of the Atlantic Forest is clearly and urgently needed.
Widely distributed phoretic blister beetles usually display unstructured geographic patterns of genetic diversity within species, resulting from recurrent long-dispersal events across their range. To investigate the extent of this pattern in the phoretic genus Lampromeloe, and particularly in western Mediterranean and European populations of L. variegatus, we performed: (1) a phylogeographic analysis based on fragments of the mitochondrial genes COI and 16S, and (2) a morphological revision based on qualitative and morphometric traits. Two allopatric lineages were recovered within L. variegatus, one distributed across Europe and the other in North Africa. These lineages are readily distinguishable based on morphological traits. We conclude that these lineages constitute two diagnosable evolutionary units and, consequently, we describe the North African populations as a new species, Lampromeloe pantherinus sp. nov. The new species is closely related to L. variegatus, from which it differs mainly by the elytral macrosculpture and by the shape of male genitalia. The elytral macrosculpture of L. pantherinus is somewhat similar to that of L. cavensis, a species widely distributed in the lowlands of the Mediterranean Basin. However, these two non-sister species can be distinguished by the morphology and macrosculpture of the pronotum and by the shape of the male genitalia.
The first sawfly from the Oligocene of Céreste (Southern France (Hymenoptera: Tenthredinidae)
(2024)
Luberotenthredo cerestensis gen. et sp. nov. is the first record of the sawfly family Tenthredinidae from the Oligocene of Céreste (Southern France). This taxon is described and illustrated based on a well-preserved specimen. This genus resembles the extant genus Perineura (subfamily Tenthredininae, tribe Perineurini) with which it shares forewing venation similarities and numerous morphological characters. This new taxon is the first fossil representative of the tribe Perineurini and can be used as a calibration point for future investigation of the diversification of the family Tenthredinidae.
The koinobiont endoparasitoid genus Triraphis Ruthe, 1855 (Rogadinae Foerster, 1863) is a group of braconid wasps that contains 74 species distributed along the Nearctic, Neotropical, Oriental and Palearctic regions. We amplified a fragment of the cytochrome oxidase subunit I (COI) for 19 specimens of Triraphis from the Chamela Biological Station (CBS), a region mainly composed of tropical dry forest near the Pacific coast of Jalisco, Mexico. Based on genetic distances among specimens of Triraphis from the CBS and all COI sequences of BINs assigned to Triraphis and Rogas Nees, 1819 available in the BOLDSYSTEMS database, we identified three clusters in the CBS that correspond with T. bradzlotnicki Sharkey, 2021, T. davidwahli Sharkey, 2021 and T. defectus Valerio, 2015, which were previously described from Costa Rica. Based on morphology, we identified individuals of T. fusciceps Cresson, 1869 and provided COI sequences of this species for the first time. Four genetic clusters of Triraphis correspond to four new species that are described here: T. kardia sp. nov., T. ocellatus sp. nov., T. divergens sp. nov. and T. luzabrilae sp. nov. Since T. bradzlotnicki and T. davidwahli were exclusively described with molecular data (COI), we morphologically described them based on Mexican specimens.
Marie Franzos, 1870–1941
(2024)
Die aus Wien stammende Marie Franzos darf als produktivste Übersetzerin und Vermittlerin der skandinavischen Literatur ihrer Zeit gelten. Sie brachte zwischen 1896 und 1938 insgesamt 112 Bücher von 33 Schriftstellern aus dem Schwedischen, Dänischen und Norwegischen ins Deutsche, darunter Werke von Selma Lagerlöf und Per Hallström.
Palaeosphryon menatensis gen. et sp. nov., first unambiguous representative of the longhorn beetle subfamily Prioninae from the Paleocene of Menat (France), is described and illustrated. The new fossil is placed into the tribe Prionini, showing some similarities with some species of the extant genera Osphryon (Papua New Guinea) and Titanus (Brazil, Colombia, Guianas, Ecuador, Peru), viz. in general body shape, antennomere 3 as long as first and second together but shorter than the length of fourth plus fifth, elongate elytra, and small spines on the lateral margin of the pronotum disposed in a relatively similar way as in Osphryon. Nevertheless, the exact affinities of the new fossil within the Prionini remain uncertain because of the lack of a recent phylogenetic analysis in which it could be integrated. This fossil beetle is exceptional for its very large size, with a body 70 mm long. Some other large longhorn beetles have been found in the same outcrop, and are awaiting description. The positions of the previously described Cerambycidae from Menat are also discussed. This exceptional fauna of Cerambycidae is in accordance with the current palaeoenvironmental reconstruction for the Menat Konservat-Lagerstätte, as a small maar lake surrounded by a warm and humid, probably evergreen forest.
A new family of Cyphophthalmi with disjunct Mediterranean distribution, Parasironidae fam. nov., is proposed. The new family comprises four genera and seven species. Cimmerosiro gen. nov., Tirrenosiro gen. nov. and Ebrosiro gen. nov. are described as new genera, and Tirrenosiro axeli gen. et sp. nov., Cimmerosiro krivolutskyi gen. et sp. nov., C. juberthiei gen. et sp. nov. and C. rhodiensis gen. et sp. nov. as new species. Parasironidae stands out by a set of characteristics that we recognize as predominantly plesiomorphic. These characteristics and the present distribution indicate the great age of the family, probably early Mesosoic. We attribute its origin to the western part of the Cimmerian terrane, and its current distribution and diversification of the major clades to geotectonic events during the Mesozoic. Additionally, a new sensory organ (sensilla) has been discovered in Cyphophthalmi. This organ is located on the pedipalp coxae and is believed to have a potential hygroreceptive function.
The monotypic banchine ichneumonid genus Shortia is rediscovered after 39 years, based on two new species from India, far away from the type locality in Australia: S. karumban Ranjith sp. nov. and S. manjapulli Ranjith sp. nov., collected from the Western Ghats, India. The generic concept of Shortia is revised. Both new species and the type species of the genus, S. siccula Gauld, 1984, are illustrated. A taxonomic key for the identification of species of Shortia is provided and the possible causes for the disjunct distribution are discussed.
The “trachystreptoform” species of Spirostreptidae, i.e., species which would formerly have been ascribed to the tribe Trachystreptini, from the Udzungwa Mountains are (re)described, including one new genus and five new species: Attemsostreptus reflexus Akkari & Enghoff, 2019, A. cataractae Enghoff sp. nov., A. leptoptilos Enghoff sp. nov., A. julostriatus Enghoff sp. nov., Lophostreptus tersus (Cook, 1896) (= L. ptilostreptoides Carl, 1909 syn. nov.), L. magombera Enghoff sp. nov., and Udzungwastreptus marianae Enghoff gen. et sp. nov. The type material of Lophostreptus regularis Attems, 1909 (= L. tersus) is discussed. The discussion includes paragraphs on the classification and the Udzungwa fauna of Spirostreptidae, on grouping of the Udzungwa trachystreptoform species in relation to altitude, and on the possibly recent immigration of A. reflexus and L. tersus into the Udzungwa Mts.
Known by many names, the Chinese banyan (Ficus microcarpa L.) is a monoecious plant species originating from south-eastern Asia which has been introduced as an ornamental in numerous areas outside its native range, including the Mediterranean. Like every species of Ficus, it is associated with a series of chalcid wasp species, known as fig wasps. These species are distributed in the families Agaonidae, Epichrysomallidae, Eurytomidae, Ormyridae and Pteromalidae. In this publication, we describe a new species of Ormyrus Westwood, 1832 (Hymenoptera, Chalcidoidea, Ormyridae), O. microcarpae Askew & Koutsoukos sp. nov., reared from figs of F. microcarpa collected from Greece and Cyprus. The new species is compared with O. lini and O. watshami. This species is likely to be a parasitoid of Meselatus bicolor Chen, 1999 (Hymenoptera, Epichrysomallidae). In addition, the previously unknown female of O. lini is also described and illustrated. This publication constitutes the first report of species of Ormyrus associated with figs in Europe.
Six species of the spider genus Spinirta Jin & Zhang, 2020 from southern China (Araneae: Corinnidae)
(2024)
In the current study, six species of the genus Spinirta from southern China are recognized, four new species are described: S. hongyui Wang, Lu & Z.S. Zhang sp. nov. (♂♀), S. liuae Wang, Lu & Z.S. Zhang sp. nov. (♂♀), S. simianshan Wang, Lu & Z.S. Zhang sp. nov. (♂♀) and S. yintiaoling Wang, Lu & Z.S. Zhang sp. nov. (♂). Females of S. aviforma Jin & Zhang, 2020 (♂♀) and S. quadrata Jin & Zhang, 2020 (♂♀) are described for the first time. Photos of the body and copulatory organs, as well as the locality map are provided.
The ammonoids of the family Maenioceratidae from Givetian sedimentary rocks of the Anti-Atlas (Morocco) are investigated. The study is based on new collections stored in the Museum für Naturkunde, Berlin. The genera Maenioceras Schindewolf, 1933 and Afromaenioceras Göddertz, 1987 are revised; the genus Trimaenioceras is newly described. The species Maenioceras afroterebratum sp. nov., Maenioceras mzerrebense sp. nov., Maenioceras oufranense sp. nov., Maenioceras beckeri sp. nov., Afromaenioceras sulcatostriatum (Bensaïd, 1974), Afromaenioceras hiemale sp. nov., Afromaenioceras bensaidi sp. nov., Afromaenioceras brumale sp. nov., Afromaenioceras crassum (Bensaïd, 1974), Trimaenioceras klugi gen. et sp. nov., Trimaenioceras eculeus gen. et sp. nov., Trimaenioceras fuscina gen. et sp. nov. and Trimaenioceras paucum gen. et sp. nov. are described in detail.
A remarkable morphologically and genetically distinct species of the genus Ero C.L. Koch, 1836 is described based on both sexes from the cloud forest of the island of Saint Helena: Ero lizae sp. nov. Another new species, Ero natashae sp. nov., is also described on the basis of morphological differences in the male and female genitalia. Both species were initially reported a single species, Ero aphana (Walckenaer, 1802), from the island by Unzicker (1977).
High resolution images are provided for type specimens of Platygastroidea (Hymenoptera: Apocrita) in the Hope Entomological Collections, Oxford University. We formally resurrect Trissoscelio Kieffer revised status to accommodate T. bifasciata (Dodd) new combination, T. indica (Mani) new combination, T. nigriceps Kieffer revised combination, T. ruficeps Kieffer revised combination, and T. punctaticeps Kieffer revised combination. Paridris subplana (Dodd) new combination is transferred from Sceliacantha Dodd to Paridris Kieffer and treated as a senior synonym of P. coorgensis Sharma.
ZooBank registration. urn:lsid:zoobank.org:pub:EB97FE10-B01D-4D45-AF6E-D247ED0040BE
Two new species and one new genus of Lamiinae (Coleoptera: Cerambycidae) are described in Acanthocinini: Embera flava new species, new genus, from Panama; and Nealcidion lingafelteri new species from Costa Rica. The species-group name of Nealcidion napoensis Nascimento and McClarin, 2018 is corrected and morphological variations in Leptostylus cristulatus Bates, 1872 are reported. Trypanidius mimicavus Carelli, Monné, and Souza, 2013 is redescribed and transferred to Carphina Bates, 1872, forming the new combination Carphina mimicavus. Colombicallia curta Galileo and Martins, 1992 (Calliini) is recorded from Panama for the first time.
ZooBank registration. urn:lsid:zoobank.org:pub:7DD2EF0F-7DC9-4A85-83DA-10F4EE8CA8CB
A first-time analysis of taxonomically relevant characters, functional morphology, geographic distribution, ecoregion preference, and hypothetical host spiders of Pepsis basifusca Lucas (Hymenoptera: Pompilidae: Pepsinae) is presented. This analysis is compared with other Nearctic species in Vardy’s (2005) Pepsis menechma species-group, particularly P. cerberus Lucas and P. elegans Lepeletier which are suspected parasitoids of trapdoor spiders. Pepsis basifusca females differ from females of these species in possessing a rounded gena-postgena in dorsal view; straight mid and hind tibial spurs; short hind tibial inner spur; and short, very stout, and backward slanted hind tibial bristles. Pepsis basifusca Level III Ecoregions comprise mountains, plateaus, highlands, and tablelands, often at high elevation (~3,000–5,000 feet (914–1,524 meters), from Utah, Colorado, Kansas, and Missouri to Panama. Pepsis basifusca, the smallest Nearctic congener, should be expected to capture comparatively small mygalomorph spiders like some other species in Vardy’s (2005) Pepsis menechma species-group. Based on taxonomic, morphological, biogeographical, and potential host spider criteria, P. basifusca should probably be removed from this group and transferred to another species-group.
ZooBank registration. urn:lsid:zoobank.org:pub:4D3BF37C-3358-4C25-B56A-104C57301AE2
Identifications of recently collected Eucnemidae (Coleoptera: Elateroidea) borrowed from two collections have resulted in the discovery of two new species: Entomophthalmus abbreviatus Otto (Cuba) and Trigonopleurus cordobaalfaroi Otto (Guatemala and Louisiana, USA). Images of the two newly described species along with two New World Entomophthalmus Bonvouloir species for comparative purposes are included.
ZooBank registration. urn:lsid:zoobank.org:pub:E83B2AC6-33ED-4680-8F2E-4E455A26D4C8
Five new state records for Idaho in the genera Agrilus Curtis, Anthaxia Eschscholtz, and Buprestis Linnaeus (Coleoptera: Buprestidae) are included herein, with brief comments thereon. Two of the species are believed to be introduced. Agrilus liragus Barter and Brown is elevated to a full species, resurrected status.
ZooBank registration. urn:lsid:zoobank.org:pub:3AE72784-F368-45A2-AC90-B31E48D0D5CC
Sixteen species of Issidae (Hemiptera: Fulgoromorpha) were recorded in a single day of collecting in Dong Son-Ky Thuong Nature Reserve, Quang Ninh Province, Vietnam, of which a checklist is provided. Among them, eight species are new to science and described in different tribes and subtribes: in the Hemisphaeriini Hemisphaeriina: Gergithoides olivaceus sp. nov., Hemisphaerius bresseeli sp. nov. and Neogergithoides scapularis sp. nov.; Hemisphaeriini Mongolianina: Mongoliana vietnamica sp. nov.; Kodaianellini: Kodaianella mua sp. nov.; Parahiraciini Parahiraciina: Pusulissus quangninhensis sp. nov. and Rostrolatum curviceps sp. nov.; Sarimini: Pseudocoruncanius obliquus sp. nov. The new genus Melichergithus gen. nov. is described to accommodate Gergithus gravidus Melichar, 1906 and the new combination Melichergithus gravidus (Melichar, 1906) gen. et comb. nov. is proposed; a black form of the species is recorded for the first time and described. Two species, Longieusarima lunulia Wang, Bourgoin & Zhang, 2017 and Parallelissus fuscus Meng, Qin & Wang, 2020, are recorded from Vietnam for the first time, while another species Maculergithus luteomaculatus (Constant & Pham, 2016) is recorded for the first time from Quang Ninh Province. Four species were represented by single females that could not be identified to species level, belonging to the genera Clypeosmilus Gnezdilov & Soulier-Perkins, 2017, Fortunia Distant, 1909 (two species) and Kodaianellissus Wang, Bourgoin & Zhang, 2017. The five following genera are recorded from Vietnam for the first time: Kodaianella Fennah, 1956, Rostrolatum Che, Zhang & Wang, 2020, Longieusarima Wang, Bourgoin & Zhang, 2017, Parallelissus Meng, Qin & Wang, 2020 and Kodaianellissus. The type material of Hemisphaerius rufovarius Walker, 1858 and its junior synonyms H. scymnoides Walker, 1862, H. testaceus Distant, 1906 and H. virescens Distant, 1906 was studied and the male terminalia described; as a result, H. rufovarius is removed from the fauna of Vietnam and China. Hemisphaerius bipunctatus Melichar, 1906 is also removed from the fauna of Vietnam after examination of the corresponding specimens. This study provides a 25% increase in the number of Issidae of Vietnam; a complete list of the 51 species recorded from the country, as well as a map of the number of recorded species per province, are given and discussed.
A new family-level taxon of deep-sea isopods, Basoniscus hikurangi gen. et sp. nov., was recovered from the Hikurangi Plateau in the deep sea off eastern New Zealand. The broad-bodied, eyeless, seemingly unremarkable isopod was unusual in its possession of features that characterize two different families: the shallow water Joeropsididae Nordenstam, 1933 and the deep-sea Haploniscidae Hansen, 1916. An analysis of superfamily Janiroidea G.O. Sars, 1897 was conducted to establish the affinities of the species. Multiple analyses were done using unweighted and implied weighted characters. Existing families were well supported, with B. hikurangi intermediate between Joeropsididae and Haploniscidae. The new species, however, cannot be placed in either family owing to its lack of important defining synapomorphies of each family. As a result, Basoniscidae fam. nov. was created to contain this new species. That rocky hard substrates are undersampled is another implication. Our understanding of deep-sea species richness will not be accurate until more efforts are made to survey these habitats, especially more sites in the southern hemisphere. These gaps in our knowledge of the deep sea impairs any general claims about the distribution of biodiversity on a global scale. This find demonstrates that museums hold underused but valuable resources for understanding and describing the biodiversity of the deep sea.
Type specimens of Oedionychina Chapuis, 1875 described by Fabricius from the Kiel collection are examined and illustrated. Lectotypes are designated for the following species: Chrysomela albicollis Fabricius, 1787; Chrysomela nobilitata Fabricius, 1787; Chrysomela quadrifasciata Fabricius, 1787; Chrysomela quadriguttata Fabricius, 1781; Galleruca atomaria Fabricius, 1801; Galleruca decemguttata Fabricius, 1801; Galleruca fasciata Fabricius, 1798; Galleruca humeralis Fabricius, 1801; Galleruca lunata Fabricius, 1801; Galleruca nitida Fabricius, 1801; Galleruca obsoleta Fabricius, 1801; Galleruca petaurista Fabricius, 1801; Galleruca quadrinotata Fabricius, 1798; Galleruca sellata Fabricius, 1801. The species status is restored for Chrysomela quadriguttata Fabricius, 1781 and Alagoasa areata (Germar, 1824) comb. nov. The following new combinations are proposed: Phenrica quadriguttata (Fabricius, 1781), Asphaera nitida (Fabricius, 1801), Phenrica obsoleta (Fabricius, 1801), Alagoasa areata areata (Germar, 1824), Alagoasa areata decempunctata (Latreille, 1833), Alagoasa areata escuintla Bechyné, 1955, Alagoasa areata macromela Bechyné, 1958, Alagoasa areata praecessa Bechyné, 1959, Alagoasa areata recuperata Bechyné, 1959; all comb. nov. New placement: Galleruca avicenniae Fabricius, 1792 is removed from Alticini and placed in Galerucini incertae sedis; Galleruca trifasciata Fabricius, 1801 is removed from Chrysomelidae and placed in genus Ora Clark, 1865 (Scirtidae Fleming, 1821).
The genus Spaeleoleptes was proposed by H. Soares in 1966 to accommodate the first Brazilian troglobitic species of harvestmen, Spaeleoleptes spaeleus H. Soares, 1966. In this work, we redescribe this species, including digital images of the type material and drawings of the male genitalia. Since its description, Spaeleoleptes has remained monotypic, and after 56 years, herein is described the second species of the genus, the troglobitic Spaeleoleptes gimli sp. nov. Both species share sexually dimorphic legs I and II with modified regions and swelling on the tibiae and patellae I and II; a penis with robust conductors covering all or part of the capsula interna and a capsula interna with two lateral projections. They are clearly separated by the shape of the modified region of the tibia; by the presence of an apical projection on the apical lamina of the pars distalis in S. spaeleus; and the lateral projections of the capsula interna, which is flattened in S. gimli. Spaeleoleptes gimli greatly increases the distributional range of the genus, as it is now recorded from caves located in two Brazilian phytophysiognomies from the Cerrado of Minas Gerais to the Caatinga of Bahia.
Several adult female monstrilloid copepods, collected in March 2022 from the protected reef area of Xcalak, on the southern part of the Mexican Caribbean coast, proved to belong to two undescribed species of Monstrilla Dana, 1849. They are described here as M. xcalakensis sp. nov. and M. annulata sp. nov., partly by use of scanning electron microscopy. Females of the two species are generally similar but differ in: (1) antennular segmental structure, (2) antennular armature and ornamentation, (3) structure and setation of the fifth leg, (4) number and modifications of the caudal setae, and (5) integumental ornamentation. Comparison with congeneric species revealed distinctive features for both species that support their status as new. These two species are interesting additions to the reef-dwelling monstrilloid copepod fauna of the Mexican Caribbean and confirm Monstrilla as the most diverse genus of monstrilloids in this area, now represented by nine species.
SAFE Update February 2024
(2024)
Otto Holzapfel, Liedverzeichnis [Hildesheim: Olms, 2006], online Update März 2024. Dateien: Lieder, Lexikon, ergänzende Dateien - Eine erste [...] Fassung dieses "Lexikons" wurde gedruckt: O.Holzapfel, Lexikon folkloristischer Begriffe und Theorien (Bern 1996; Studien zur Volksliedforschung,17). Inhalt und Umfang sind seitdem in Form eines "Zettelkastens" erheblich erweitert worden. Das Lexikon von 1996 griff bewusst auf das "Handbuch des Volksliedes" (1973/75) zurück.
Otto Holzapfel, Liedverzeichnis [Hildesheim: Olms, 2006], online Update März 2024. Dateien: Lieder, Lexikon, ergänzende Dateien - Eine erste [...] Fassung dieses "Lexikons" wurde gedruckt: O.Holzapfel, Lexikon folkloristischer Begriffe und Theorien (Bern 1996; Studien zur Volksliedforschung,17). Inhalt und Umfang sind seitdem in Form eines "Zettelkastens" erheblich erweitert worden. Das Lexikon von 1996 griff bewusst auf das "Handbuch des Volksliedes" (1973/75) zurück.
This thesis contains three theoretical works about certain aspects of the interplay of electronic correlations and topology in the Hubbard model.
In the first part of this thesis, the applicability of elementary band representations (EBRs) to diagnose interacting topological phases, that are protected by spatial symmetries and time-reversal-symmetry, in terms of their single-particle Matsubara Green’s functions is investigated. EBRs for the Matsubara Green’s function in the zero-temperature limit can be defined via the topological Hamiltonian. It is found that the Green’s function EBR classification can only change by (i) a gap closing in the spectral function at zero frequency, (ii) the Green’s function becoming singular i.e. having a zero eigenvalue at zero frequency or (iii) the Green’s function breaking a protecting symmetry. As an example, the use of the EBRs for Matsubara Green’s functions is demonstrated on the Su-Schriefer-Heeger model with exact diagonalization.
In the second part the Two-Particle Self-Consistent approach (TPSC) is extended to include spin-orbit coupling (SOC). Time-reversal symmetry, that is preserved in the presence of SOC, is used to derive new TPSC self-consistency equations including SOC. SOC breaks spin rotation symmetry which leads to a coupling of spin and charge channel. The local and constant TPSC vertex then consists of three spin vertices and one charge vertex. As a test case to study the interplay of Hubbard interaction and SOC, the Kane-Mele-Hubbard model is studied. The antiferromagnetic spin fluctuations are the leading instability which confirms that the Kane-Mele-Hubbard model is an XY antiferromagnet at zero temperature. Mixed spin-charge fluctuations are found to be small. Moreover, it is found that the transversal spin vertices are more strongly renormalized than the longitudinal spin vertex, SOC leads to a decrease of antiferromagnetic spin fluctuations and the self-energy shows dispersion and sharp features in momentum space close to the phase transition.
In the third part TPSC with SOC is used to calculate the spin Hall conductivity in the Kane-Mele-Hubbard model at finite temperature. The spin Hall conductivity is calculated once using the conductivity bubble and once including vertex corrections. Vertex corrections for the spin Hall conductivity within TPSC corresponds to the analogues of the Maki-Thompson contributions which physically correspond to the excitation and reabsorption of a spin, a charge or a mixed spin-charge excitation by an electron. At all temperatures, the vertex corrections show a large contribution in the vicinity of the phase transition to the XY antiferromagnet where antiferromagnetic spin fluctuations are large. It is found that vertex corrections are crucial to recover the quantized value of −2e^2/h in the zero-temperature limit. Further, at non-zero temperature, increasing the Hubbard interaction leads to a decrease of the spin Hall conductivity. The results indicate that scattering of electrons off antiferromagnetic spin fluctuations renormalize the band gap. Decreasing the gap can be interpreted as an effective increase of temperature leading to a decrease of the spin Hall conductivity.
Highlights
• Three ecological groups were identified based on distributional patterns.
• Old assessments were confirmed with the latest occurrence data.
• For each group, we derived different population trends in times of global change.
• Global change elevates importance of vector-borne diseases.
• Our results serve as base for effective Simuliidae monitoring.
Abstract
The black fly genus Simulium includes medically and ecologically important species, characterized by a wide variation of ecological niches largely determining their distributional patterns. In a rapidly changing environment, species-specific niche characteristics determine whether a species benefits or not. With aquatic egg, larval and pupal stages followed by a terrestrial adult phase, their spatial arrangements depend upon the interplay of aquatic conditions and climatic-landscape parameters in the terrestrial realm. The aim of this study was to enhance the understanding of the distributional patterns among Simulium species and their ecological drivers. In an ecological niche modelling approach, we focused on 12 common black fly species with different ecological requirements. Our modelling was based on available distribution data along with five stream variables describing the climatic, land-cover, and topographic conditions of river catchments. The modelled freshwater habitat suitability was spatially interpolated to derive an estimate of the adult black flies' probability of occurrence. Based on similarities in the spatial patterns of modelled habitat suitability we were able to identify three biogeographical groups, which allows us to confirm old assessments with current occurrence data: (A) montane species, (B) broad range species and (C) lowland species. The five veterinary and human medical relevant species Simulium equinum, S. erythrocephalum, S. lineatum, S. ornatum and S. reptans are mainly classified in the lowland species group. In the course of climatic changes, it is expected that biocoenosis will slightly shift towards upstream regions, so that the lowland group will presumably emerge as the winner. This is mainly explained by wider ecological niches, including a higher temperature tolerance and tolerance to various pollutants. In conclusion, these findings have significant implications for human and animal health. As exposure to relevant Simulium species increases, it becomes imperative to remain vigilant, particularly in investigating the potential transmission of pathogens.
Highlights
• We study dormancy in the ‘rare mutation’ regime of stochastic adaptive dynamics.
• We first derive the polymorphic evolution sequence, based on prior work.
• Our evolutionary branching criterion extends a result by Champagnat and Méléard.
• In a classical model dormancy can favour evolutionary branching.
• Dormancy also affects several more population characteristics.
Abstract
In this paper, we investigate the consequences of dormancy in the ‘rare mutation’ and ‘large population’ regime of stochastic adaptive dynamics. Starting from an individual-based micro-model, we first derive the Polymorphic Evolution Sequence of the population, based on a previous work by Baar and Bovier (2018). After passing to a second ‘small mutations’ limit, we arrive at the Canonical Equation of Adaptive Dynamics, and state a corresponding criterion for evolutionary branching, extending a previous result of Champagnat and Méléard (2011).
The criterion allows a quantitative and qualitative analysis of the effects of dormancy in the well-known model of Dieckmann and Doebeli (1999) for sympatric speciation. In fact, quite an intuitive picture emerges: Dormancy enlarges the parameter range for evolutionary branching, increases the carrying capacity and niche width of the post-branching sub-populations, and, depending on the model parameters, can either increase or decrease the ‘speed of adaptation’ of populations. Finally, dormancy increases diversity by increasing the genetic distance between subpopulations.
Measurements of the production cross sections of prompt D0, D+, D∗+, D+s, Λ+c, and Ξ+c charm hadrons at midrapidity in proton−proton collisions at s√=13 TeV with the ALICE detector are presented. The D-meson cross sections as a function of transverse momentum (pT) are provided with improved precision and granularity. The ratios of pT-differential meson production cross sections based on this publication and on measurements at different rapidity and collision energy provide a constraint on gluon parton distribution functions at low values of Bjorken-x (10−5−10−4). The measurements of Λ+c (Ξ+c) baryon production extend the measured pT intervals down to pT=0(3)~GeV/c. These measurements are used to determine the charm-quark fragmentation fractions and the cc¯¯ production cross section at midrapidity (|y|<0.5) based on the sum of the cross sections of the weakly-decaying ground-state charm hadrons D0, D+, D+s, Λ+c, Ξ0c and, for the first time, Ξ+c, and of the strongly-decaying J/psi mesons. The first measurements of Ξ+c and Σ0,++c fragmentation fractions at midrapidity are also reported. A significantly larger fraction of charm quarks hadronising to baryons is found compared to e+e− and ep collisions. The cc¯¯ production cross section at midrapidity is found to be at the upper bound of state-of-the-art perturbative QCD calculations.
The Chiral Magnetic Wave (CMW) phenomenon is essential to provide insights into the strong interaction in QCD, the properties of the quark-gluon plasma, and the topological characteristics of the early universe, offering a deeper understanding of fundamental physics in high-energy collisions. Measurements of the charge-dependent anisotropic flow coefficients are studied in Pb-Pb collisions at center-of-mass energy per nucleon-nucleon collision sNN−−−√= 5.02 TeV to probe the CMW. In particular, the slope of the normalized difference in elliptic (v2) and triangular (v3) flow coefficients of positively and negatively charged particles as a function of their event-wise normalized number difference, is reported for inclusive and identified particles. The slope rNorm3 is found to be larger than zero and to have a magnitude similar to rNorm2, thus pointing to a large background contribution for these measurements. Furthermore, rNorm2 can be described by a blast wave model calculation that incorporates local charge conservation. In addition, using the event shape engineering technique yields a fraction of CMW (fCMW) contribution to this measurement which is compatible with zero. This measurement provides the very first upper limit for fCMW, and in the 10-60% centrality interval it is found to be 26% (38%) at 95% (99.7%) confidence level.
Measurements of charged-particle production in pp, p−Pb, and Pb−Pb collisions in the toward, away, and transverse regions with the ALICE detector are discussed. These regions are defined event-by-event relative to the azimuthal direction of the charged trigger particle, which is the reconstructed particle with the largest transverse momentum (ptrigT) in the range 8<ptrigT<15 GeV/c. The toward and away regions contain the primary and recoil jets, respectively; both regions are accompanied by the underlying event (UE). In contrast, the transverse region perpendicular to the direction of the trigger particle is dominated by the so-called UE dynamics, and includes also contributions from initial- and final-state radiation. The relative transverse activity classifier, RT=NTch/⟨NTch⟩, is used to group events according to their UE activity, where NTch is the charged-particle multiplicity per event in the transverse region and ⟨NTch⟩ is the mean value over the whole analysed sample. The energy dependence of the RT distributions in pp collisions at s√=2.76, 5.02, 7, and 13 TeV is reported, exploring the Koba-Nielsen-Olesen (KNO) scaling properties of the multiplicity distributions. The first measurements of charged-particle pT spectra as a function of RT in the three azimuthal regions in pp, p−Pb, and Pb−Pb collisions at sNN−−−√=5.02 TeV are also reported. Data are compared with predictions obtained from the event generators PYTHIA 8 and EPOS LHC. This set of measurements is expected to contribute to the understanding of the origin of collective-like effects in small collision systems (pp and p−Pb).
Measurements of charged-particle production in pp, p−Pb, and Pb−Pb collisions in the toward, away, and transverse regions with the ALICE detector are discussed. These regions are defined event-by-event relative to the azimuthal direction of the charged trigger particle, which is the reconstructed particle with the largest transverse momentum (ptrigT) in the range 8<ptrigT<15 GeV/c. The toward and away regions contain the primary and recoil jets, respectively; both regions are accompanied by the underlying event (UE). In contrast, the transverse region perpendicular to the direction of the trigger particle is dominated by the so-called UE dynamics, and includes also contributions from initial- and final-state radiation. The relative transverse activity classifier, RT=NTch/⟨NTch⟩, is used to group events according to their UE activity, where NTch is the charged-particle multiplicity per event in the transverse region and ⟨NTch⟩ is the mean value over the whole analysed sample. The energy dependence of the RT distributions in pp collisions at s√=2.76, 5.02, 7, and 13 TeV is reported, exploring the Koba-Nielsen-Olesen (KNO) scaling properties of the multiplicity distributions. The first measurements of charged-particle pT spectra as a function of RT in the three azimuthal regions in pp, p−Pb, and Pb−Pb collisions at sNN−−−√=5.02 TeV are also reported. Data are compared with predictions obtained from the event generators PYTHIA 8 and EPOS LHC. This set of measurements is expected to contribute to the understanding of the origin of collective-like effects in small collision systems (pp and p−Pb).
Aspekte Schwarzer Geschichte(n) in "Berlin Global" : eine Führungs- und Ausstellungsreflexion
(2024)
Februar ist Black History Month und damit der ideale Zeitpunkt, eine Blogserie über Berliner Orte zu beginnen, die wir - Gianna Zocco und Sandra Folie - im Zuge unseres neuen Forschungsprojekts "Schwarze Narrative transkultureller Aneignung" besuchen: Museen, Theater, Verlage, Archive usw., die für eine afroeuropäisch fokussierte Literatur- und Kulturforschung relevant sind und mit denen wir ins Gespräch kommen wollen. Die erste Exkursion führte mich zur Ausstellung BERLIN GLOBAL im Humboldt Forum, die zu zeigen versucht, "wie die Stadt und ihre Menschen mit der Welt verbunden sind". Sie beruft sich dabei auf eine vielstimmige, partizipative Konzeption und Umsetzung und beschäftigt sich intensiv mit dem Thema des Kolonialismus und seinen Nachwirkungen. Unter dem Titel "Sichtbar werden" führten eine externe afrodeutsche Expertin und eine Museumsvermittlerin im Gespräch - miteinander, aber auch mit der Gruppe - durch die Spuren Schwarzer Geschichte(n) in der Ausstellung. Welche Aspekte Schwarzer Geschichte(n) müssen aber in einer solchen Ausstellung erst im Rahmen einer speziellen Führung "sichtbar werden", fragte ich mich vorab. Und würde sich die Führung mit ihrem Anspruch der Sichtbarmachung als ein Akt des 'narrating back' und damit der partiellen oder temporären Aneignung eines (zu) weiß kodierten Raumes wie des Humboldt Forums begreifen lassen? Die Expertin, die den thematischen Fokus setzte, war Tanja-Bianca Schmidt, freie Kuratorin und Kunsthistorikerin an der TU Dresden mit den Schwerpunkten Black Identity, rassismuskritische Kunstgeschichte, Ästhetik der Migration und Postkoloniale Theorie. Zusätzlich zu ihrer beruflichen Expertise brachte sie ihre persönlichen Erfahrungen als Schwarze Deutsche mit ein. Sophie Eliot, die als Outreach-Spezialistin für das Stadtmuseum Berlin tätig ist und sich in der diskriminierungskritischen und -sensiblen Museumsarbeit verortet, war ihre Gesprächspartnerin.
The elliptic flow (v2) of D0 mesons from beauty-hadron decays (non-prompt D0) was measured in midcentral (30-50%) Pb-Pb collisions at a centre-of-mass energy per nucleon pair sNN−−−√ = 5.02 TeV with the ALICE detector at the LHC. The D0 mesons were reconstructed at midrapidity (|y|<0.8) from their hadronic decay D0→K−π+, in the transverse momentum interval 2<pT<12 GeV/c. The result indicates a positive v2 for non-prompt D0 mesons with a significance of 2.7σ. The non-prompt D0-meson v2 is lower than that of prompt non-strange D mesons with 3.2σ significance in 2<pT<8 GeV/c, and compatible with the v2 of beauty-decay electrons. Theoretical calculations of beauty-quark transport in a hydrodynamically expanding medium describe the measurement within uncertainties.
Controlling and understanding electron correlations in quantum matter is one of the most challenging tasks in materials engineering. In the past years a plethora of new puzzling correlated states have been found by carefully stacking and twisting two-dimensional van der Waals materials of different kind. Unique to these stacked structures is the emergence of correlated phases not foreseeable from the single layers alone. In Ta-dichalcogenide heterostructures made of a good metallic “1H”- and a Mott insulating “1T”-layer, recent reports have evidenced a cross-breed itinerant and localized nature of the electronic excitations, similar to what is typically found in heavy fermion systems. Here, we put forward a new interpretation based on first-principles calculations which indicates a sizeable charge transfer of electrons (0.4-0.6 e) from 1T to 1H layers at an elevated interlayer distance. We accurately quantify the strength of the interlayer hybridization which allows us to unambiguously determine that the system is much closer to a doped Mott insulator than to a heavy fermion scenario. Ta-based heterolayers provide therefore a new ground for quantum-materials engineering in the regime of heavily doped Mott insulators hybridized with metallic states at a van der Waals distance.
Trait-dependent effects of biotic and abiotic filters on plant regeneration in Southern Ecuador
(2024)
Tropical forests have always fascinated scientists due to their unique biodiversity. However, our understanding of ecological processes shaping the complexity of tropical rainforests is still relatively poor. Plant regeneration is one of the processes that remain understudied in the tropics although this is a key process defining the structure, diversity and assembly of tropical plant communities. In my dissertation, I combine experimental, observational and trait-based approaches to identify processes shaping the assembly of seedling communities and compare associations between environmental conditions and plant traits across plant life stages. By working along a steep environmental gradient in the tropical mountains of Southern Ecuador, I was able to investigate how processes of plant regeneration vary in response to biotic and abiotic factors in tropical montane forests.
My dissertation comprises three complementary chapters, each addressing an individual research question. First, I studied how trait composition in plant communities varies in relation to the broad- and local-scale environmental conditions and across the plant life cycle. I measured key traits reflecting different ecological strategies of plants that correspond to three stages of the plant life cycle (i.e., adult trees, seed rain and recruiting seedlings). I worked on 81 subplots along an elevational gradient covering a large climatic gradient at three different elevations (1000, 2000 and 3000 m a.s.l.). In addition, I measured soil and light conditions at the local spatial scale within each subplot. My findings show that the trait composition of leaves, seeds and seedlings changed similarly across the elevational gradient, but that the different life stages responded differently to the local gradients in soil nutrients and light availability. Consequently, my findings highlight that trait-environment associations in plant communities differ between large and small spatial scales and across plant life stages.
Second, I investigated how seed size affects seedling recruitment in natural forests and in pastures in relation to abiotic and biotic factors. I set up a seed sowing experiment in both habitat types and sowed over 8,000 seeds belonging to seven tree species differing in seed size. I found that large-seeded species had higher proportions of recruitment in the forests compared to small-seeded species. However, small-seeded species tended to recruit better in pastures compared to large-seeded species. I showed that high surface temperature was the main driver of differences in seedling recruitment between habitats, because it limited seedling recruitment of large-seeded species. The results from this experiment show that pasture restoration requires seed addition of large-seeded species and active protection of recruiting seedlings in order to mitigate harmful conditions associated with high temperatures in deforested areas.
Third, I examined the associations between seedling beta-diversity and different abiotic and biotic factors between and within elevations. I applied beta-diversity partitioning to obtain two components of beta-diversity: species turnover and species richness differences. I associated these components of beta-diversity with biotic pressures by herbivores and fungal pathogens and environmental heterogeneity in light and soil conditions. I found that species turnover in seedling communities was positively associated with the dissimilarity in biotic pressures within elevations and with environmental heterogeneity between elevations. Further, I found that species richness differences increased primarily with increasing environmental heterogeneity within elevations. My findings show that the associations between beta-diversity of seedling communities and abiotic and biotic factors are scale-dependent, most likely due to differences in species sorting in response to biotic pressures and species coexistence in response to environmental heterogeneity.
My dissertation reveals that studying processes of community assembly at different plant life stages and spatial scales can yield new insights into patterns and processes of plant regeneration in tropical forests. I investigated how community assembly processes are governed by abiotic and biotic filtering across and within elevations. I also experimentally explored how the process of seedling recruitment depends on seed size-dependent interactions, and verified how these effects are associated with abiotic and biotic filtering. Identifying such processes is crucial to inform predictive models of environmental change on plant regeneration and successful forest restoration. Further exploration of plant functional traits and their associations with local-scale environmental conditions could effectively support local conservation efforts needed to enhance forest cover in the future and halt the accelerating loss of biodiversity.
Highlights
• 153 chemicals of emerging concern detected in complex multi-component mixtures.
• 108 possible mixture risk assessment scenarios were investigated.
• Non-detects, QSARs, and experimental ecotoxicological data were integrated for risk assessment.
• 8 chemicals were the main risk drivers in at least one site across the River Aconcagua basin.
Abstract
Environmental risk assessments strategies that account for the complexity of exposures are needed in order to evaluate the toxic pressure of emerging chemicals, which also provide suggestions for risk mitigation and management, if necessary. Currently, most studies on the co-occurrence and environmental impacts of chemicals of emerging concern (CECs) are conducted in countries of the Global North, leaving massive knowledge gaps in countries of the Global South.
In this study, we implement a multi-scenario risk assessment strategy to improve the assessment of both the exposure and hazard components in the chemical risk assessment process. Our strategy incorporates a systematic consideration and weighting of CECs that were not detected, as well as an evaluation of the uncertainties associated with Quantitative Structure-Activity Relationships (QSARs) predictions for chronic ecotoxicity. Furthermore, we present a novel approach to identifying mixture risk drivers. To expand our knowledge beyond well-studied aquatic ecosystems, we applied this multi-scenario strategy to the River Aconcagua basin of Central Chile. The analysis revealed that the concentrations of CECs exceeded acceptable risk thresholds for selected organism groups and the most vulnerable taxonomic groups. Streams flowing through agricultural areas and sites near the river mouth exhibited the highest risks. Notably, the eight risk drivers among the 153 co-occurring chemicals accounted for 66–92 % of the observed risks in the river basin. Six of them are pesticides and pharmaceuticals, chemical classes known for their high biological activity in specific target organisms.
• Zahlen und Maßsysteme sind bereits aus dem antiken Ägypten und aus Mesopotamien belegt. Im 4. Jahrtausend vor unserer Zeitrechnung haben sich mit der hierarchisierten Gesellschaft auch Zahl- und Schriftzeichen entwickelt. Sie dienten vor allem der Zuteilung von Ressourcen.
• Die 13 Bücher der »Elemente« von Euklid (3. Jahrhundert vor unserer Zeit) sind die früheste erhaltene axiomatisch-deduktiv aufgebaute Sammlung mathematischen Wissens. Die Begeisterung für dieses Werk hielt über Jahrhunderte an.
• Die Ordnung von Beobachtungen durch die mathematische Erfassung und Auswertung von Daten ist in Wissenschaft und Alltag selbstverständlich. Mathematische Techniken der Statistik und Kartierung halfen Dr. John Snow im 19. Jahrhundert, die Ausbreitung der Cholera zu erforschen und zu bekämpfen.
• Trotzdem stößt die Mathematik bei der Schaffung von Ordnungen auch an Grenzen: Denn es gibt weder eine Garantie noch eine Anleitung für deren bestmögliche Nutzung. Dies zeigen nicht zuletzt Krisen wie die Coronapandemie oder die Klimakrise.
Der Anblick ist überwältigend. Ein buntes Sammelsurium der unterschiedlichsten Dinge, die sich dicht an dicht in den Fächern des raumhohen Regals drängen, eine Steilwand aus Wimmelbildern im Wunderkammer-Format. Wenn wir die Fächer allerdings genauer betrachten, stellt sich allmählich der Eindruck ein, dass es doch so etwas wie eine Ordnung der Dinge gibt. Nur welche?
Im Rahmen dieser publikationsbasierten Dissertation wurden drei wissenschaftliche Arbeiten veröffentlicht. Als Erstautorenschaft wurde 2022 die Arbeit “Effectiveness of High-intensity Focused Ultrasound (HIFU) Therapy of Solid and Complex Benign Thyroid Nodules - A Long-term Follow up Two-center Study.” im Journal “Experimental and Clinical Endocrinology & Diabetes” veröffentlicht. Im Folgenden wird der Inhalt dieser Arbeit dargelegt. Ein kurzer Überblick über die Ergebnisse der anderen beiden mitpublizierten Arbeiten findet sich im Kapitel „Weitere Ergebnisse der Arbeitsgruppe“.
Durch die hohe Prävalenz benigner Schilddrüsenknoten sind deren Behandlungsalternativen von großem wissenschaftlichem Interesse. Dabei bildet die nebenwirkungsarme, minimalinvasive Thermoablation mittels high-intensity focused ultrasound (HIFU) eine attraktive Alternative zu herkömmlichen Verfahren wie der Schilddrüsenchirurgie oder der Radioiodtherapie. Bei der HIFU-Echotherapie werden die Schilddrüsenknoten auf 80 - 90 Grad Celsius erhitzt, sodass eine irreversible Koagulationsnekrose entsteht. Um den Therapieprozess und die Indikationsstellung von HIFU bei benignen Schilddrüsenknoten zu optimieren, ist es notwendig, genaue Studien durchzuführen.
Ziel der vorliegenden bizentrischen Langzeitstudie war, die Effektivität von HIFU-Echotherapien bei benignen Schilddrüsenknoten zu evaluieren und erstmalig den Einfluss der Knotenmorphologie auf den Therapieerfolg zu untersuchen. Vor der Therapie und in regelmäßigen Intervallen nach der Therapie wurden die Größe und die Morphologie der Schilddrüsenknoten mittels Ultraschall dokumentiert. In der retrospektiven Studie wurden Daten von 58 Patienten ausgewertet. Dabei wurde die Gesamtpopulation in eine Gruppe mit soliden und in eine Gruppe mit komplexen Knoten eingeteilt. Die durchschnittliche prozentuale Volumenreduktion in jeder Gruppe wurde mit dem Wilcoxon-Signed-Rank Test statistisch analysiert.
Die Gesamtpopulation zeigte eine Volumenreduktion der zuvor abladierten Knoten von 38.86 % nach 3 Monaten (Spannweite: 4.03 % - 91.16 %, p < 0.0001, n = 25), 42.7 % nach 6 Monaten (Spannweite: 7.36 % - 93.2 %, p < 0.0001, n = 18), 62.21 % nach 9 Monaten (Spannweite: 12.88 % - 93.2 %, p = 0.0078, n = 8) und 61.42 % nach 12 Monaten (Spannweite: 39.39 % - 93.2 %, p > 0.05, n = 4). Die soliden Knoten hatten eine Volumenreduktion von 49.98 % nach 3 Monaten (Spannweite: 4.03 % - 91.16 %, p = 0.0001, n = 15), 46.40 % nach 6 Monaten (Spannweite: 7.36 % - 93.2 %, p = 0.001, n = 11), 65.77 % nach 9 Monaten (Spannweite: 39.39 % - 93.2 %, p = 0.0156, n = 7) und 63.88 % nach 12 Monaten (Spannweite: 39.39 % - 93.2%, p > 0.05, n = 2). Komplexe Knoten hatten eine Volumenreduktion von 35.2 % nach 3 Monaten (Spannweite: 5.85 % - 68.63 %, p = 0.002, n = 10), 36.89 % nach 6 Monaten (Spannweite: 12.23 % - 68.63 %, p = 0.0156, n = 7) und 63.64 % nach 12 Monaten (Spannweite: 52,38 % - 73.91 %, p > 0.05, n = 2).
In der vorliegenden bizentrischen Langzeitstudie wurde deutlich, dass HIFU-Echotherapie eine effektive Behandlungsoption benigner Schilddrüsenknoten ist. Erstmalig gezeigt wurde der Trend, dass solide Knoten besser auf HIFU-Echotherapie ansprechen als komplexe Knoten.
Anhand der gewonnenen Ergebnisse und der neuen Erkenntnisse zum Einfluss der Knotenmorphologie auf die HIFU-Echotherapie benigner Schilddrüsenknoten kann HIFU als Therapieoption besser bewertet werden. Eine differenziertere Indikationsstellung in Bezug auf solide und komplexe Knoten wird ermöglicht und die HIFU-Echotherapie kann gegen andere thermoablative Verfahren abgewogen werden.
This thesis develops a naturalist theory of phenomenal consciousness. In a first step, it is argued on phenomenological grounds that consciousness is a representational state and that explaining consciousness requires a study of the brain’s representational capacities. In a second step, Bayesian cognitive science and predictive processing are introduced as the most promising attempts to understand mental representation to date. Finally, in a third step, the thesis argues that the so-called “hard problem of consciousness” can be resolved if one adopts a form of metaphysical anti-realism that can be motivated in terms of core principles of Bayesian cognitive science.
Highlights
• An airport can result in high particle concentrations in a distant residential area.
• The particle size distribution indicated the airport as the main source of particles.
• Lower air traffic during the COVID-19 pandemic lead to lower particle concentrations.
• The particle concentration showed high temporal variations.
Abstract
Exposure to ultrafine particles has a significant influence on human health. In regions with large commercial airports, air traffic and ground operations can represent a potential particle source. The particle number concentration was measured in a low-traffic residential area about 7 km from Frankfurt Airport with a Condensation Particle Counter in a long-term study. In addition, the particle number size distribution was determined using a Fast Mobility Particle Sizer.
The particle number concentrations showed high variations over the entire measuring period and even within a single day. A maximum 24 h-mean of 24,120 cm−3 was detected. Very high particle number concentrations were in particular measured when the wind came from the direction of the airport. In this case, the particle number size distribution showed a maximum in the particle size range between 5 and 15 nm. Particles produced by combustion in jet engines typically have this size range and a high potential to be deposited in the alveoli. During a period with high air traffic volume, significantly higher particle number concentrations could be measured than during a period with low air traffic volume, as in the COVID-19 pandemic.
A large commercial airport thus has the potential to lead to a high particle number concentration even in a distant residential area. Due to the high particle number concentrations, the critical particle size, and strong concentration fluctuations, long-term measurements are essential for a realistic exposure analysis.
Correlations in azimuthal angle extending over a long range in pseudorapidity between particles, usually called the "ridge" phenomenon, were discovered in heavy-ion collisions, and later found in pp and p−Pb collisions. In large systems, they are thought to arise from the expansion (collective flow) of the produced particles. Extending these measurements over a wider range in pseudorapidity and final-state particle multiplicity is important to understand better the origin of these long-range correlations in small-collision systems. In this Letter, measurements of the long-range correlations in p−Pb collisions at sNN−−−√=5.02 TeV are extended to a pseudorapidity gap of Δη∼8 between particles using the ALICE, forward multiplicity detectors. After suppressing non-flow correlations, e.g., from jet and resonance decays, the ridge structure is observed to persist up to a very large gap of Δη∼8 for the first time in p−Pb collisions. This shows that the collective flow-like correlations extend over an extensive pseudorapidity range also in small-collision systems such as p−Pb collisions. The pseudorapidity dependence of the second-order anisotropic flow coefficient, v2({\eta}), is extracted from the long-range correlations. The v2(η) results are presented for a wide pseudorapidity range of −3.1<η<4.8 in various centrality classes in p−Pb collisions. To gain a comprehensive understanding of the source of anisotropic flow in small-collision systems, the v2(η) measurements are compared to hydrodynamic and transport model calculations. The comparison suggests that the final-state interactions play a dominant role in developing the anisotropic flow in small-collision systems.
We investigate the applicability of the well-known multilevel Monte Carlo (MLMC) method to the class of density-driven flow problems, in particular the problem of salinisation of coastal aquifers. As a test case, we solve the uncertain Henry saltwater intrusion problem. Unknown porosity, permeability and recharge parameters are modelled by using random fields. The classical deterministic Henry problem is non-linear and time-dependent, and can easily take several hours of computing time. Uncertain settings require the solution of multiple realisations of the deterministic problem, and the total computational cost increases drastically. Instead of computing of hundreds random realisations, typically the mean value and the variance are computed. The standard methods such as the Monte Carlo or surrogate-based methods are a good choice, but they compute all stochastic realisations on the same, often, very fine mesh. They also do not balance the stochastic and discretisation errors. These facts motivated us to apply the MLMC method. We demonstrate that by solving the Henry problem on multi-level spatial and temporal meshes, the MLMC method reduces the overall computational and storage costs. To reduce the computing cost further, parallelization is performed in both physical and stochastic spaces. To solve each deterministic scenario, we run the parallel multigrid solver ug4 in a black-box fashion.
Irgendwann ist jede Revolution zu Ende. An die Stelle revolutionärer Unordnung tritt eine neue Ordnung. Wann das genau passiert, ist nicht einfach festzustellen. Das liegt nicht nur daran, dass die Forschung sich viel mehr für die Ursachen und Anlässe von Revolutionen interessiert. Es liegt auch daran, wie Revolutionen enden.
Ordnungen sind enorm vielschichtig. Innerhalb einer Gemeinschaft, eines Staates leben wir immer schon – teilweise unhinterfragt – in einem Geflecht von Ordnungen, die sich überlagern, ergänzen und zum Teil auch widersprechen. Der Beitrag nähert sich diesen unterschiedlichen Dimensionen von Ordnungen und ihren Verschränkungen und stellt diese punktuell vor. Im zweiten Teil fokussiert er sich auf die Risiken demokratischer Ordnungen, die ein immer weiter um sich greifender Populismus mit sich bringt. Was dagegen hilft? Hierauf werden Antworten gesucht – nicht zuletzt bei Jürgen Habermas.
Les Républicains in Frankreich, die Tories in Großbritannien, die österreichischen Christdemokraten: Parteien, die jahrzehntelang als feste politische Größe in ihren Ländern galten, haben einen rapiden Bedeutungsverlust erlebt, manche sind in Richtung des rechten Randes gerückt. Doch eine gemäßigt konservative Kraft rechts der Mitte ist notwendig für eine stabile und zukunftsoffene Demokratie.
Warum in der Politik so viel von »Architektur« gesprochen wird und warum Architektur an sich nicht demokratisch sein kann, darüber hat sich der Architekturhistoriker Carsten Ruhl Gedanken gemacht
Globalisierung, Migration, neue Geschlechterverhältnisse, Bildungsexpansion: Dies alles verändert unsere sozialen Strukturen. Wie wirkt sich dieser Wandel auf Gesellschaft und Individuum aus? Diesen Fragen geht die DFG-Forschungsgruppe RISS (»Reconfiguration and Internalization of Social Structure«) nach.
Wie funktioniert die Verneinung in der Sprache? Und wie hängen die sprachlichen Strukturen hierfür mit der Wahrnehmung im Gehirn zusammen? Solchen Fragen widmet sich der neue Sonderforschungsbereich 1629 »Negation: Ein sprachliches und außersprachliches Phänomen« (NegLaB) an der Goethe-Universität. Bereits in die dritte Förderphase geht ein SFB aus der Biochemie, der sich mit der selektiven Autophagie befasst, einem natürlichen Vorgang, mit dem Zellen fehlerhafte oder überflüssige Bestandteile gezielt entsorgen können.
The Åland Islands archipelago enjoys a special international status sui generis, which essentially encompasses demilitarisation, neutralisation, and autonomy. This status is guaranteed under international law by the agreements of 1921, 1940, and 1947, which are still in force. Furthermore, there are convincing reasons to assume that the Åland Islands regime has grown into European customary law. By virtue of her international (treaty) obligations, Finland cannot unilaterally change this status under the present conditions, irrespective of domestic (constitutional) decisions. While integration into NATO’s collective defence system and the EU’s Common Security and Defence Policy structures is compatible with the special status of the Åland Islands, care must be taken by Finland and her partners to ensure that the obligations arising from these developments are fulfilled in accordance with the demilitarised and neutralised status of the archipelago. This includes that the use by Finnish troops for preventive defence, beyond the exceptions laid down in the 1921 Åland Agreement, is only permitted in the case (of threat) of an immediate and clearly identifiable attack.
The autonomous character of the Åland Islands was established under a League of Nations dispute settlement and implemented, inter alia, in Finnish legislation. Its essence even grew into customary law. The arrangements of 1921, however, do not constitute a bilateral treaty between Finland and Sweden. The UN assumes that the international mechanism to protect Åland’s autonomy did not become obsolete with the demise of the League of Nations, but was only “suspended until such time as an express decision has been taken by the United Nations to put it back into force”. A corresponding proposal could be submitted, in any case, both by Finland and/or Sweden or possibly even by any other UN member state, for discussion in the Sixth Committee. However, the final decision to re-activate this special mechanism would have to be adopted by the UN General Assembly.
EU Law applies to the Åland Islands in principle; however, Finland’s Accession Treaty to the EU to which Protocol No. 2 on the Åland Islands was annexed, established a number of specific rules which are still in force today. This, most notably, results in the limited application of value added tax and excise duties in the Åland Islands. Therefore, the rules on customs procedures apply with respect to the movement of goods to and from the Åland Islands. In addition, other provisions of Union law, in particular those relating to fundamental freedoms and European state aid law, may be relevant in view of the special fiscal status of the Åland Islands. However, assessing individual cases would require further information and in-depth studies. Irrespective of the requirements set out in the said Protocol, the EU is obliged to respect the national identity of Member States pursuant to Article 4 para. 2 TEU; this obligation includes respect for the special status of the Åland Islands under both international and Finnish constitutional law.