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Die vorliegende Arbeit, die im Rahmen des zwischen 2011 und 2013 durchgeführten Forschungsprojektes „Förderung von Modellbildungs- und Falsifikationsprozessen im Elementar- und Primarbereich“ entstanden ist, untersuchte auf Grundlage neuerer entwicklungspsychologischer Forschungsbefunde die Möglichkeiten der Förderung im naturwissenschaftlichen Denken bei Kindern im Elementarbereich. Nach der theoretischen Einordnung des Themas und der Darstellung der Forschungslage wurden im empirischen Teil in einem ersten Schritt die Kompetenzen beim Schlussfolgern im Themengebiet Elastizität und Plastizität und beim Wissenschaftsverständnis von Kindern im Alter von vier bis zehn Jahren, eingeteilt in vier Altersstufen, ermittelt; weiterhin wurden die Verknüpfungen beider Kompetenzbereiche untersucht. Als Instrumente dienten ein bereits erprobter Schlussfolgerungstest sowie ein neu entwickelter Test zur Kompetenzmessung von Wissenschaftsverständnis. In der Grundschule wurden die Tests jeweils als Gruppentests und im Kindergarten als Einzeltests durchgeführt. Die Stichprobe um-fasste 142 Kinder, 82 Kinder aus dem Primarbereich und 60 Kinder aus dem Elementarbereich. Beim Schlussfolgern zeigte sich, dass es für Kinder aller einbezogenen Altersgruppen deutlich leichter war, mit Ereignissen umzugehen, die eine Vermutung bestätigen, als mit solchen, die eine Vermutung widerlegen. Zudem stellte sich heraus, dass der Umgang mit Ereignissen, die im Hinblick auf eine Vermutung irrelevant sind, noch schwieriger war. Mit zunehmendem Alter war eine Kompetenzsteigerung erkennbar. Die Analyse der Tests ergab außerdem einen Zusammenhang zwischen Wissenschaftsverständnis und Schlussfolgern sowie einen deutlichen Einfluss exekutiver Funktionen. Im zweiten Schritt wurden zwei ausgewählte Trainingsmaß-nahmen zur Förderung der Koordination von Theorie und Evidenz bei Kindern im Alter von fünf bis sechs Jahren auf ihre Wirksamkeit hin geprüft, und zwar einerseits durch die Unter-stützung mit adaptivem Nachfragen bei fehlerhaften Antworten sowie andererseits durch eine intensive Förderung mit Modellierung. Die an einer Stichprobe von 63 Kindern durchgeführte Trainingsstudie war als Prä-Post-Studie angelegt und umfasste die Überprüfung des erworbenen Wissens. Die Studie ergab, dass die intensiv geförderten Kinder deutlich höhere Kompetenzen erworben hatten als die durch adaptive Unterstützung unterstützten Probanden. Außer-dem wurde ein Transfer-Test im Inhaltsgebiet Schwimmen und Sinken durchgeführt; hierbei wurden beide Trainingsgruppen in gleicher Weise mit adaptivem Nachfragen unterstützt. Dabei zeigten Kinder beider Trainingsgruppen deutlich höhere Kompetenzen beim Schlussfolgern als im Post-Test, dennoch zeigten Kinder mit vorheriger intensiver Förderung durch Modellierung wiederum höhere Kompetenzen im Transfer-Test als Kinder aus der Gruppe mit adaptiver Unterstützung. Abschließend wurde noch ein Argumentationstest durchgeführt, bei dem Kinder aller drei Experimentalgruppen (Trainingsgruppe 1, Trainingsgruppe 2, Kontrollgruppe) über-greifende Kompetenzen beim Schlussfolgern zeigen konnten. In diesem Test zeigte sich zwischen den drei Gruppen kein Unterschied im Hinblick auf angemessene Antworten beim Schlussfolgern.
In April and May 2012 data on Au+Au collisions at beam energies of Ekin = 1.23A GeV were recorded with the High Acceptance Di-Electron Spectrometer, which is located at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany. At this beam energy all hadrons containing strangeness are produced below their elementary production threshold. The required energy is not available in binary NN collisions but must be provided by the system e.g. through multi-particle interactions or medium effects like a modified in-medium potential (e.g. KN/ΛN potential). Thus, a high sensitivity to these medium effects is expected in the investigated system.
The baryon-dominated systems created in relativistic heavy-ion collisions (HIC) at SIS18 energies reach densities of about 2-3 times ground state density p0 and may be similar to the properties of matter expected in the inner core of neutron stars. It is in particular the behavior of hadrons containing strangeness, i.e. kaons and hyperons, and their potentials in the dense medium which may have severe implications on astrophysical objects and processes. As ab-initio calculations of quantum chromodynamics (QCD) cannot be performed rigorously on the lattice at finite baryo-chemical potentials due to the fermion sign problem, effective descriptions have to be used in order to model properties of dense systems and the involved particles. The only way to access the in-medium potential of strange hadrons above nuclear ground state density p0 is by comparing data from relativistic HIC to such effective microscopic models. Up to now, not much data on neutral kaons and Λ hyperons are available from heavy collision systems close to their NN production threshold. These two electromagnetically uncharged strange hadrons are in particular well suited to study their potential in a dense nucleon-dominated environment as their kinematic spectra are not affected by Coulomb interactions.
We study the sensitivities of the directed flow in Au+Au collisions on the equation of state (EoS), employing the transport theoretical model JAM. The EoS is modified by introducing a new collision term in order to control the pressure of a system by appropriately selecting an azimuthal angle in two-body collisions according to a given EoS. It is shown that this approach is an efficient method to modify the EoS in a transport model. The beam energy dependence of the directed flow of protons is examined with two different EoS, a first-order phase transition and crossover. It is found that our approach yields quite similar results as hydrodynamical predictions on the beam energy dependence of the directed flow; Transport theory predicts a minimum in the excitation function of the slope of proton directed flow and does indeed yield negative directed flow, if the EoS with a first-order phase transition is employed. Our result strongly suggests that the highest sensitivity for the critical point can be seen in the beam energy range of 4.7 ≤√sNN≤11.5GeV.
Ecocriticism started out in the early 1990s in the framework of American literary studies - in the Anglo sense that equates "America" with the "United States." In fact, the new field's first professional organization, the Association for the Study of Literature and the Environment, was founded as an offshoot of academic interest focused on a particular region of the United States, in the backroom of a casino in Reno, Nevada, during the 1992 annual convention of the Western Literature Association. During its first decade, the bulk of ecocritical attention focused on American literature as shaped by Thoreau and British literature as shaped by Wordsworth - a limited but powerful concentration on nature writing in the genres of poetry, nonfiction prose, and the noveI, with particular attention to Native American literature. By the turn of the millennium, in a story that has by now been told repeatedly, interest in the literature-environment nexus had grown and diversified enough that ecocriticism almost literally exploded into a much broader research area encompassing multiple historical periods (from the Middle Ages to postmodernism), genres (from poetry to the graphic novel and narrative film), and regions: the Caribbean, Latin America, East Asia, and Western Europe all emerged as new areas of ecocritical exploration. New encounters between postcolonial theory and ecocritical analysis proved particularly productive for both fields: linking historical exploration and political ecology with literary analysis, the emergent "poco-eco" matrix opened new perspectives on the connections and disjunctures between imperialism, ecological crisis, and conservation. Over the last few years, the concept of "Environmental Humanities" has increasingly co me to accompany and to superimpose itself as an umbrella term on ecocriticism and comparable research areas in neighboring disciplines: environmental history, environmental anthropology, environmental philosophy, cultural geography, and political ecology. Driven by the impulse to connect environmental research across the humanities, to justify humanistic research at institutions often prone to cut first in the humanities, and to bring the knowledge generated through humanistic research into the public sphere, environmentally oriented scholars have used the term "Environmental Humanities" as a shorthand for what they hope will be a new vision of their discipline. As of this writing, the concept remains somewhat more aspirational than real. While ecocritics and environmental philosophers have long collaborated in Australia, and environmental historians and ecocritics sometimes collaborate in the United States, the disciplines that make up the Environmental Humanities have to date largely pursued their own disciplinary trajectories. But there are signs that the tide may have begun to turn. Various universities and research organizations have started programs in the field. The Swedish environmental historian Sverker Sörlin published a brief outline of the new interdisciplinary matrix in the journal 'BioScience' in 2012, and a longer manifesto followed from the editorial collective of the newly established journal 'Environmental Humanities' at Macquarie University in Australia (Rose et al. 2012). Another journal focusing on the environmental humanities began publication in early 2014 from the University of Oregon under the title 'Resilience'.
Cancer is characterized by a remarkable intertumoral, intratumoral, and cellular heterogeneity that might be explained by the cancer stem cell (CSC) and/or the clonal evolution models. CSCs have the ability to generate all different cells of a tumor and to reinitiate the disease after remission. In the clonal evolution model, a consecutive accumulation of mutations starting in a single cell results in competitive growth of subclones with divergent fitness in either a linear or a branching succession. Acute lymphoblastic leukemia (ALL) is a highly malignant cancer of the lymphoid system in the bone marrow with a dismal prognosis after relapse. However, stabile phenotypes and functional data of CSCs in ALL, the so-called leukemia-initiating cells (LICs), are highly controversial and the question remains whether there is evidence for their existence. This review discusses the concepts of CSCs and clonal evolution in respect to LICs mainly in B-ALL and sheds light onto the technical controversies in LIC isolation and evaluation. These aspects are important for the development of strategies to eradicate cells with LIC capacity. Common properties of LICs within different subclones need to be defined for future ALL diagnostics, treatment, and disease monitoring to improve the patients’ outcome in ALL.
Local treatment of unresectable colorectal liver metastases : results of a randomized phase II trial
(2017)
Background: Tumor ablation is often employed for unresectable colorectal liver metastases. However, no survival benefit has ever been demonstrated in prospective randomized studies. Here, we investigate the long-term benefits of such an aggressive approach.
Methods: In this randomized phase II trial, 119 patients with unresectable colorectal liver metastases (n < 10 and no extrahepatic disease) received systemic treatment alone or systemic treatment plus aggressive local treatment by radiofrequency ablation ± resection. Previously, we reported that the primary end point (30-month overall survival [OS] > 38%) was met. We now report on long-term OS results. All statistical tests were two-sided. The analyses were according to intention to treat.
Results: At a median follow up of 9.7 years, 92 of 119 (77.3%) patients had died: 39 of 60 (65.0%) in the combined modality arm and 53 of 59 (89.8%) in the systemic treatment arm. Almost all patients died of progressive disease (35 patients in the combined modality arm, 49 patients in the systemic treatment arm). There was a statistically significant difference in OS in favor of the combined modality arm (hazard ratio [HR] = 0.58, 95% confidence interval [CI] = 0.38 to 0.88, P = .01). Three-, five-, and eight-year OS were 56.9% (95% CI = 43.3% to 68.5%), 43.1% (95% CI = 30.3% to 55.3%), 35.9% (95% CI = 23.8% to 48.2%), respectively, in the combined modality arm and 55.2% (95% CI = 41.6% to 66.9%), 30.3% (95% CI = 19.0% to 42.4%), 8.9% (95% CI = 3.3% to 18.1%), respectively, in the systemic treatment arm. Median OS was 45.6 months (95% CI = 30.3 to 67.8 months) in the combined modality arm vs 40.5 months (95% CI = 27.5 to 47.7 months) in the systemic treatment arm.
Conclusions: This phase II trial is the first randomized study demonstrating that aggressive local treatment can prolong OS in patients with unresectable colorectal liver metastases.
Genetic mutations underlying neurodegenerative disorders impair ribosomal DNA (rDNA) transcription suggesting that nucleolar dysfunction could be a novel pathomechanism in polyglutamine diseases and in certain forms of amyotrophic lateral sclerosis/frontotemporal dementia. Here, we investigated nucleolar activity in pre-symptomatic digenic models of Parkinson's disease (PD) that model the multifactorial aetiology of this disease. To this end, we analysed a novel mouse model mildly overexpressing mutant human α-synuclein (hA53T-SNCA) in a PTEN-induced kinase 1 (PINK1/PARK6) knockout background and mutant mice lacking both DJ-1 (also known as PARK7) and PINK1. We showed that overexpressed hA53T-SNCA localizes to the nucleolus. Moreover, these mutants show a progressive reduction of rDNA transcription linked to a reduced mouse lifespan. By contrast, rDNA transcription is preserved in DJ-1/PINK1 double knockout (DKO) mice. mRNA levels of the nucleolar transcription initiation factor 1A (TIF-IA, also known as RRN3) decrease in the substantia nigra of individuals with PD. Because loss of TIF-IA, as a tool to mimic nucleolar stress, increases oxidative stress and because DJ-1 and PINK1 mutations result in higher vulnerability to oxidative stress, we further explored the synergism between these PD-associated genes and impaired nucleolar function. By the conditional ablation of TIF-IA, we blocked ribosomal RNA (rRNA) synthesis in adult dopaminergic neurons in a DJ-1/PINK1 DKO background. However, the early phenotype of these triple knockout mice was similar to those mice exclusively lacking TIF-IA. These data sustain a model in which loss of DJ-1 and PINK1 does not impair nucleolar activity in a pre-symptomatic stage. This is the first study to analyse nucleolar function in digenic PD models. We can conclude that, at least in these models, the nucleolus is not as severely disrupted as previously shown in DA neurons from PD patients and neurotoxin-based PD mouse models. The results also show that the early increase in rDNA transcription and nucleolar integrity may represent specific homeostatic responses in these digenic pre-symptomatic PD models.
Development of single-port cholecystectomy : results of a case-control study matched to one surgeon
(2012)
Background: Single-port laparoscopic cholecystectomy is an evolving technique which is now widely established. Up until now, the safety of the procedure and a respective learning curve have not been adequately reported in most studies. The aim of this study was to demonstrate that single-port cholecystectomy is a safe procedure, with a positive learning curve from a case-control study matched to one surgeon.
Methods: One hundred single-port cholecystectomies performed by one surgeon (AB) were retrospectively matched to 100 patients who underwent conventional laparoscopic cholecystectomy carried out by the same surgeon. The two groups were matched in respect of surgical indication, gender, age, and body mass index. The groups were compared with respect to operation time, use of additional trocars, analgesics required in the post anesthesia care unit, postoperative complications, and duration of hospital stay.
Results: No significant difference was found between the two groups with respect to postoperative complications and stay in hospital. The operation time increased slightly in the single-port group. Directly after the operation, the analgesic use required in the post anesthesia care unit was higher in the single-port group. Consumption of analgesics on the surgical ward was very similar in each group. In respect to the learning curve, the operation time and use of additional trocars showed a positive trend, starting with the thirtieth operation.
Conclusion: Single-port cholecystectomy is a feasible and safe procedure in a specialist setting. The procedure can be done under the same safety rules as those for conventional laparoscopic cholecystectomy. Considering the learning curve, starting with the thirtieth operation, a positive trend was seen. Long-term studies will be needed to establish the incidence and rate of incisional hernias.
This post hoc analysis of a phase 3 trial explored the effect of pixantrone in patients (50 pixantrone, 47 comparator) with relapsed or refractory aggressive B-cell non-Hodgkin lymphoma (NHL) confirmed by centralized histological review. Patients received 28-d cycles of 85 mg/m2 pixantrone dimaleate (equivalent to 50 mg/m2 in the approved formulation) on days 1, 8 and 15, or comparator. The population was subdivided according to previous rituximab use and whether they received the study treatment as 3rd or 4th line. Median number of cycles was 4 (range, 2–6) with pixantrone and 3 (2–6) with comparator. In 3rd or 4th line, pixantrone was associated with higher complete response (CR) (23·1% vs. 5·1% comparator, P = 0·047) and overall response rate (ORR, 43·6% vs. 12·8%, P = 0·005). In 3rd or 4th line with previous rituximab (20 pixantrone, 18 comparator), pixantrone produced better ORR (45·0% vs. 11·1%, P = 0·033), CR (30·0% vs. 5·6%, P = 0·093) and progression-free survival (median 5·4 vs. 2·8 months, hazard ratio 0·52, 95% confidence interval 0·26–1·04) than the comparator. Similar results were found in patients without previous rituximab. There were no unexpected safety issues. Pixantrone monotherapy is more effective than comparator in relapsed or refractory aggressive B-cell NHL in the 3rd or 4th line setting, independently of previous rituximab.
Relative orientation of POTRA domains from cyanobacterial Omp85 studied by pulsed EPR spectroscopy
(2016)
Many proteins of the outer membrane of Gram-negative bacteria and of the outer envelope of the endosymbiotically derived organelles mitochondria and plastids have a β-barrel fold. Their insertion is assisted by membrane proteins of the Omp85-TpsB superfamily. These proteins are composed of a C-terminal β-barrel and a different number of N-terminal POTRA domains, three in the case of cyanobacterial Omp85. Based on structural studies of Omp85 proteins, including the five POTRA-domain-containing BamA protein of Escherichia coli, it is predicted that anaP2 and anaP3 bear a fixed orientation, whereas anaP1 and anaP2 are connected via a flexible hinge. We challenged this proposal by investigating the conformational space of the N-terminal POTRA domains of Omp85 from the cyanobacterium Anabaena sp. PCC 7120 using pulsed electron-electron double resonance (PELDOR, or DEER) spectroscopy. The pronounced dipolar oscillations observed for most of the double spin-labeled positions indicate a rather rigid orientation of the POTRA domains in frozen liquid solution. Based on the PELDOR distance data, structure refinement of the POTRA domains was performed taking two different approaches: 1) treating the individual POTRA domains as rigid bodies; and 2) using an all-atom refinement of the structure. Both refinement approaches yielded ensembles of model structures that are more restricted compared to the conformational ensemble obtained by molecular dynamics simulations, with only a slightly different orientation of N-terminal POTRA domains anaP1 and anaP2 compared with the x-ray structure. The results are discussed in the context of the native environment of the POTRA domains in the periplasm.
Rezension zu "Zwischen Transfer und Vergleich. Theorien und Methoden der Literatur- und Kulturbeziehungen aus deutsch-französischer Perspektive". Hg. Christiane Solte-Gresser, Hans-Jürgen Lüsebrink und Manfred Schmeling. Stuttgart: Franz Steiner, 2013 (VICE VERSA. Deutsch-französische Kulturstudien; Bd. 5). 457 S.
The effects of aging on response time were examined in a paper-based lexical-decision experiment with younger (age 18–36) and older (age 64–75) adults, applying Ratcliff’s diffusion model. Using digital pens allowed the paper-based assessment of response times for single items. Age differences previously reported by Ratcliff and colleagues in computer-based experiments were partly replicated: older adults responded more conservatively than younger adults and showed a slowing of their nondecision components of RT by 53 ms. The rates of evidence accumulation (drift rate) showed no age-related differences. Participants with a higher score in a vocabulary test also had higher drift rates. The experiment demonstrates the possibility to use formal processing models with paper-based tests.
Objective: Loss of function mutations in PINK1 typically lead to early onset Parkinson disease (PD). Zebrafish (Danio rerio) are emerging as a powerful new vertebrate model to study neurodegenerative diseases. We used a pink1 mutant (pink−/−) zebrafish line with a premature stop mutation (Y431*) in the PINK1 kinase domain to identify molecular mechanisms leading to mitochondrial dysfunction and loss of dopaminergic neurons in PINK1 deficiency.
Methods: The effect of PINK1 deficiency on the number of dopaminergic neurons, mitochondrial function, and morphology was assessed in both zebrafish embryos and adults. Genome-wide gene expression studies were undertaken to identify novel pathogenic mechanisms. Functional experiments were carried out to further investigate the effect of PINK1 deficiency on early neurodevelopmental mechanisms and microglial activation.
Results: PINK1 deficiency results in loss of dopaminergic neurons as well as early impairment of mitochondrial function and morphology in Danio rerio. Expression of TigarB, the zebrafish orthologue of the human, TP53-induced glycolysis and apoptosis regulator TIGAR, was markedly increased in pink−/− larvae. Antisense-mediated inactivation of TigarB gave rise to complete normalization of mitochondrial function, with resulting rescue of dopaminergic neurons in pink−/− larvae. There was also marked microglial activation in pink−/− larvae, but depletion of microglia failed to rescue the dopaminergic neuron loss, arguing against microglial activation being a key factor in the pathogenesis.
Interpretation: Pink1−/− zebrafish are the first vertebrate model of PINK1 deficiency with loss of dopaminergic neurons. Our study also identifies TIGAR as a promising novel target for disease-modifying therapy in PINK1-related PD. Ann Neurol 2013;74:837–847
Stroke is a major public health issue worldwide. The prevalence of stroke in 2010 was 33 million, with 16.9 million people having a first stroke.1 Stroke was the second‐leading cause of death behind heart disease globally, accounting for over 10% of total deaths worldwide.
Stroke is a heterogeneous condition that can be due to rupture of a blood vessel (hemorrhagic) or to blockage of a vessel (ischemic). About 85% of strokes are ischemic in origin and these are often classified by mechanism. This should be distinguished from risk factors such as hypertension, diabetes, smoking, etc. Risk factors increase the risk of stroke but do not necessarily explain the mechanism of a particular stroke. About 25% of ischemic strokes have a radiographic appearance similar to that seen in patients with cardioembolic sources (such as atrial fibrillation [AF], prosthetic valves, valvular prolapse, or mitral valve regurgitation), but no embolic source is found. These "cryptogenic strokes" (CS; also called embolic strokes of undetermined source) pose a particular clinical challenge in that the optimal antithrombotic therapy to reduce recurrence is uncertain. Since there are currently no data to support long‐term oral anticoagulation (OAC) in CS, but also no specific trials that have addressed this question, guidelines recommend antiplatelet therapy. Identification of AF in these patients changes the most likely mechanism to cardioembolism, and thus changes the recommended antithrombotic therapy to OAC, which is extremely effective in preventing stroke in patients with AF.
This report is based on discussions held at The Diagnostics and Monitoring Stroke Focus Group, a meeting held on January 15 to 17, 2015. The meeting focused on CS as a healthcare issue, and the utility of extended cardiac monitoring for AF in patients with strokes of unknown origin. The objectives of the meeting were to review existing information on the subject, define areas where knowledge was lacking or limited, and discuss study designs by which information gaps might be filled.
In European Robins, Erithacus rubecula, the magnetic compass is lateralized in favor of the right eye/left hemisphere of the brain. This lateralization develops during the first winter and initially shows a great plasticity. During the first spring migration, it can be temporarily removed by covering the right eye. In the present paper, we used the migratory orientation of robins to analyze the circumstances under which the lateralization can be undone. Already a period of 1½ h being monocularly left-eyed before tests began proved sufficient to restore the ability to use the left eye for orientation, but this effect was rather short-lived, as lateralization recurred again within the next 1½ h. Interpretable magnetic information mediated by the left eye was necessary for removing the lateralization. In addition, monocularly, the left eye seeing robins could adjust to magnetic intensities outside the normal functional window, but this ability was not transferred to the “right-eye system”. Our results make it clear that asymmetry of magnetic compass perception is amenable to short-term changes, depending on lateralized stimulation. This could mean that the left hemispheric dominance for the analysis of magnetic compass information depends on lateralized interhemispheric interactions that in young birds can swiftly be altered by environmental effects.
We investigate the properties of the QCD matter across the deconfinement phase transition in the scope of the parton-hadron string dynamics (PHSD) transport approach. We present here in particular the results on the electromagnetic radiation, i.e. photon and dilepton production, in relativistic heavy-ion collisions. By comparing our calculations for the heavy-ion collisions to the available data, we determine the relative importance of the various production sources and address the possible origin of the observed strong elliptic flow v2 of direct photons. We argue that the different centrality dependence of the hadronic and partonic sources for direct photon production in nucleusnucleus collisions can be employed to shed some more light on the origin of the photon v2 “puzzle”. While the dilepton spectra at low invariant mass show in-medium effects like an enhancement from multiple baryonic resonance formation or a collisional broadening of the vector meson spectral functions, the dilepton yield at high invariant masses (above 1.1 GeV) is dominated by QGP contributions for central heavy-ion collisions at ultra-relativistic energies. This allows to have an independent view on the parton dynamics via their electromagnetic massive radiation.
The asymmetric unit of the title compound, C18H18I2N2O2, consists of one half-molecule, completed by the application of inversion symmetry. The molecule adopts the typical structure for this class of bis-benxozazines, characterized by an anti orientation of the two benzoxazine rings around the central C—C bond. The oxazinic ring adopts a half-chair conformation. In the crystal, molecules are linked by C—I⋯N short contacts [I⋯N = 3.378 (2) Å], generating layers lying parallel to the bc plane.
Denisovite is a rare mineral occurring as aggregates of fibres typically 200–500 nm diameter. It was confirmed as a new mineral in 1984, but important facts about its chemical formula, lattice parameters, symmetry and structure have remained incompletely known since then. Recently obtained results from studies using microprobe analysis, X-ray powder diffraction (XRPD), electron crystallography, modelling and Rietveld refinement will be reported. The electron crystallography methods include transmission electron microscopy (TEM), selected-area electron diffraction (SAED), high-angle annular dark-field imaging (HAADF), high-resolution transmission electron microscopy (HRTEM), precession electron diffraction (PED) and electron diffraction tomography (EDT). A structural model of denisovite was developed from HAADF images and later completed on the basis of quasi-kinematic EDT data by ab initio structure solution using direct methods and least-squares refinement. The model was confirmed by Rietveld refinement. The lattice parameters are a = 31.024 (1), b = 19.554 (1) and c = 7.1441 (5) Å, β = 95.99 (3)°, V = 4310.1 (5) Å3 and space group P12/a1. The structure consists of three topologically distinct dreier silicate chains, viz. two xonotlite-like dreier double chains, [Si6O17]10−, and a tubular loop-branched dreier triple chain, [Si12O30]12−. The silicate chains occur between three walls of edge-sharing (Ca,Na) octahedra. The chains of silicate tetrahedra and the octahedra walls extend parallel to the z axis and form a layer parallel to (100). Water molecules and K+ cations are located at the centre of the tubular silicate chain. The latter also occupy positions close to the centres of eight-membered rings in the silicate chains. The silicate chains are geometrically constrained by neighbouring octahedra walls and present an ambiguity with respect to their z position along these walls, with displacements between neighbouring layers being either Δz = c/4 or −c/4. Such behaviour is typical for polytypic sequences and leads to disorder along [100]. In fact, the diffraction pattern does not show any sharp reflections with l odd, but continuous diffuse streaks parallel to a* instead. Only reflections with l even are sharp. The diffuse scattering is caused by (100) nanolamellae separated by stacking faults and twin boundaries. The structure can be described according to the order–disorder (OD) theory as a stacking of layers parallel to (100).
I summarize recent developments in the hard-thermal-loop approach to QCD. I first discuss a finite-temperature and -density calculation of QCD thermodynamics at NNLO from the hard-thermal-loop perturbation theory. I then discuss a generalization of the hard-thermal-loop framework to the magnetic scale g2T, from which a novel non-Abelian massless mode is uncovered.
We study a random matrix model for QCD at finite density via complex Langevin dynamics. This model has a phase transition to a phase with nonzero baryon density. We study the convergence of the algorithm as a function of the quark mass and the chemical potential and focus on two main observables: the baryon density and the chiral condensate. For simulations close to the chiral limit, the algorithm has wrong convergence properties when the quark mass is in the spectral domain of the Dirac operator. A possible solution of this problem is discussed.
The high collision energies reached at the LHC lead to significant production yields of light (anti-)nuclei and (hyper-)nuclei in proton–proton, proton–lead and, in particular, lead–lead collisions. The excellent particle identification capabilities of the ALICE apparatus, based on the specific energy loss in the Time Projection Chamber and the velocity information in the Time-Of-Flight detector, allow for the detection of these rarely produced particles. Further, the Inner Tracking System gives the possibility to separate primary nuclei from those coming from weak decay of heavier systems. One example of such a weak decay is the measurement of the (anti-)hypertriton decay to 3He + π− (3H̅e̅ + π+). The aforementioned capabilities of the ALICE apparatus offer the unique opportunity to search for exotica, like the bound state of a Λ and a neutron which would decay into a deuteron and a pion, or the bound state of two Λ’s. Results on the production of stable nuclei in Pb–Pb collisions at √sNN = 2.76 TeV are presented, and compared with thermal model predictions. We further present the current status of the searches, by their upper limits on the production yields, and compare the results to thermal and coalescence model expectations.
The pA system is typically regarded in heavy ion collisions as a “cold” nuclear matter environment and thought to isolate and identify initial state effects due to the presence of multiple nucleons in the incoming nucleus. Moreover, pA collisions bridge the gap between peripheral AA collisions and the pp baseline to create a more complete understanding of underlying production mechanisms and how they evolve with multiplicity. Recent measurements at both RHIC and the LHC provide an indication, however, that the “cold” nuclear matter picture may be somewhat naïve.
Recent LHC results from the 2013 p–Pb run at √sNN = 5.02 TeV will be discussed.
O Sentido do Direito
(2014)
Time resolved measurements of the biased disk effect at an Electron Cyclotron Resonance Ion Source
(1999)
First results are reported from time resolved measurements of ion currents extracted from the Frankfurt 14 GHz Electron Cyclotron Resonance Ion Source with pulsed biased-disk voltage. It was found that the ion currents react promptly to changes of the bias. From the experimental results it is concluded that the biased disk effect is mainly due to improvements of the extraction conditions for the source and/or an enhanced transport of ions into the extraction area. By pulsing the disk voltage, short current pulses of highly charged ions can be generated with amplitudes significantly higher than the currents obtained in continuous mode.
A small electrostatic storage ring is the central machine of the Frankfurt Ion Storage Experiments (FIRE) which will be built at the new Stern-Gerlach Center of Frankfurt University. As a true multiuser, multipurpose facility with ion energies up to 50 keV, it will allow new methods to analyze complex many-particle systems from atoms to very large biomolecules. With envisaged storage times of some seconds and beam emittances in the order of a few mm mrad, measurements with up to 6 orders of magnitude better resolutions as compared to single-pass experiments become possible. In comparison to earlier designs, the ring lattice was modified in many details: Problems in earlier designs were related to, e.g., the detection of light particles and highly charged ions with different charge states. Therefore, the deflectors were redesigned completely, allowing a more flexible positioning of the diagnostics. Here, after an introduction to the concept of electrostatic machines, an overview of the planned FIRE is given and the ring lattice and elements are described in detail.
We report on the results on the dynamical modelling of cluster formation with the new combined PHSD+FRIGA model at Nuclotron and NICA energies. The FRIGA clusterization algorithm, which can be applied to the transport models, is based on the simulated annealing technique to obtain the most bound configuration of fragments and nucleons. The PHSD+FRIGA model is able to predict isotope yields as well as hypernucleus production. Based on present predictions of the combined model we study the possibility to detect such clusters and hypernuclei in the BM@N and MPD/NICA detectors.
The properties of matter at finite baryon densities play an important role for the astrophysics of compact stars as well as for heavy ion collisions or the description of nuclear matter. Because of the sign problem of the quark determinant, lattice QCD cannot be simulated by standard Monte Carlo at finite baryon densities. I review alternative attempts to treat dense QCD with an effective lattice theory derived by analytic strong coupling and hopping expansions, which close to the continuum is valid for heavy quarks only, but shows all qualitative features of nuclear physics emerging from QCD. In particular, the nuclear liquid gas transition and an equation of state for baryons can be calculated directly from QCD. A second effective theory based on strong coupling methods permits studies of the phase diagram in the chiral limit on coarse lattices.
The topic of global trade has become central to debates on global justice and on duties to the global poor, two important concerns of contemporary political theory. However, the leading approaches fail to directly address the participants in trade and provide them with normative guidance for making choices in non-ideal circumstances. This paper contributes an account of individuals’ responsibilities for global problems in general, an account of individuals’ responsibilities as market actors, and an explanation of how these responsibilities coexist. The argument is developed through an extended case study of a consumer’s choice between conventional and fair trade coffee. My argument is that the coffee consumer’s choice requires consideration of two distinct responsibilities. First, she has responsibilities to help meet foreigners’ claims for assistance. Second, she has moral responsibilities to ensure that trades, such as between herself and a coffee farmer, are fair rather than exploitative.
Aims: The purpose of this study was to analyze the prevalence of depression, anxiety, adjustment disorders, and somatoform disorders in patients diagnosed with age-related macular degeneration (AMD) in Germany.
Methods: This study included 7,580 patients between the ages of 40 and 90 diagnosed with AMD between January 2011 and December 2014 in 1,072 primary care practices (index date). The last follow-up was in July 2016. We also included 7,580 controls without AMD, which were matched (1:1) to the AMD cases by age, sex, type of health insurance (private or statutory), physician, and Charlson comorbidity score as a generic marker of comorbidity. The outcome of the study was the prevalence of depression, anxiety, adjustment disorders, and somatoform disorders recorded in the database between the index date and the end of follow-up.
Results: The mean age among subjects was 75.7 years (SD=10.1 years), 34.0% were men, and 7.8% had private health insurance coverage. The Charlson comorbidity index was 2.0 (SD=1.8). Depression was the most frequent disease (33.7% in AMD patients versus 27.3% in controls), followed by somatoform disorders (19.6% and 16.7%), adjustment disorders (14.8% and 10.5%), and anxiety disorders (11.7% and 8.2%). Depression (OR=1.37, 95% CI: 1.27–1.47), anxiety (OR=1.50, 95% CI: 1.35–1.67), adjustment disorders (OR=1.50, 95% CI: 1.36–1.65), and somatoform disorders (OR=1.22, 95% CI: 1.12–1.32) were all positively associated with AMD.
Conclusion: Overall, a significant association was found between AMD and depression, anxiety, adjustment disorders, and somatoform disorders.
Green tea (GT) and green tea extracts (GTE) have been postulated to decrease cancer incidence. In vitro results indicate a possible effect; however, epidemiological data do not support cancer chemoprevention. We have performed a PubMED literature search for green tea consumption and the correlation to the common tumor types lung, colorectal, breast, prostate, esophageal and gastric cancer, with cohorts from both Western and Asian countries. We additionally included selected mechanistical studies for a possible mode of action. The comparability between studies was limited due to major differences in study outlines; a meta analysis was thus not possible and studies were evaluated individually. Only for breast cancer could a possible small protective effect be seen in Asian and Western cohorts, whereas for esophagus and stomach cancer, green tea increased the cancer incidence, possibly due to heat stress. No effect was found for colonic/colorectal and prostatic cancer in any country, for lung cancer Chinese studies found a protective effect, but not studies from outside China. Epidemiological studies thus do not support a cancer protective effect. GT as an indicator of as yet undefined parameters in lifestyle, environment and/or ethnicity may explain some of the observed differences between China and other countries.
Rimski novčići u ženskim srednjovekovnim grobovima sa teritorije Srbije: mogućnosti interpretacije
(2016)
U ovom radu istražuje se fenomen sekundarne upotrebe rimskih novčića (II–IV vek) u srednjovekovnim nekropolama (X–XV vek) sa teritorije Srbije. U fokusu istraživanja su grobovi u kojima su rimski novčići upotrebljeni kao dekorativni elementi pokojnikove odeće – najčešće preoblikovani u priveske. Ovakav tip sekundarne upotrebe rimskog novca konstatovan je samo u ženskim grobovima. Cilj rada je da predloži interpretaciju ove pojave kroz analizu vrednosti i značaja sekundarno upotrebljenih novčića u stvaranju porodičnih dragocenosti koje se definišu u važnim i kritičnim momentima društvenog života zajednice. Posebno se ispituje mogućnost interpretacije ovih nalaza kao primera grobova u kojima su sahranjene ženske osobe sa delovima svog miraza. Analizira se konstrukcija značenja i vrednosti ovih predmeta kroz njihovu razmenu u običajima vezanim za sklapanje braka, i, naposletku, u funerarnim praksama. Budući da je rimski novac iz ovih grobova malobrojan, i da se uvek radi o bronzanim denominacijama, možemo pretpostaviti da je definisanje njihove vrednosti i značaja zasnovano na simboličkom i reprezentativnom nivou. Polazna tačka ovog rada je korpus radova koji istražuju fenomen ponovne upotrebe stvari u prošlosti, da bi se dalje u radu dublje istražila veza između srednjovekovne društvene strukture i evaluacije novčića u seoskim zajednicama centralnog Balkana.
Depth hermeneutics—as developed by LORENZER within the framework of the Frankfort School's program of critical social research—represents a methodological and systematic approach to psychoanalytic research. The new ways and means by which a neo-Nazi utilises his visit to the Auschwitz Memorial to arouse further anti-Semitism are to be investigated by means of a scene-by-scene interpretation of his filmed appearances—first as a good-mooded tourist, then as a volatile right-wing extremist, as competent expert, and as rebellious adolescent. The aim is to demonstrate how the meaning of these role plays develops within the tension between a manifest and a latent significance. The results of this process of interpretations form the basis for clarifying the question: what patterns of socialisation are used by this "yuppie-neo-Nazi" to fascinate particularly adolescents?? In conclusion, the way in which through his post-modern film-production the producer turns Auschwitz into a test-ground where the neo-Nazi can do "a merry dance on the volcano", is analysed.
Mit der von LORENZER begründeten Tiefenhermeneutik wird eine methodologisch und methodisch reflektierte Methode psychoanalytischer Forschung vorstellt, die im Rahmen der kritischen Sozialforschung der Frankfurter Schule entwickelt wurde. Die neue Art und Weise, wie ein Neonazi einen Besuch der Gedenkstätte Auschwitz dazu benutzt, um einen neuen Antisemitismus zu erzeugen, soll durch eine szenische Interpretation seiner medialen Auftritte als gut gelaunter Tourist, als zorniger Rechtsextremist, als sachlicher Experte und als trotziger Jugendlicher untersucht werden: Es wird zu zeigen sein, wie sich die Bedeutung dieser Rollenspiele in der Spannung zwischen einem manifesten und einem latenten Sinn entfaltet. Die Ergebnisse dieses Interpretationsprozesses bilden die Grundlage für die theoretische Klärung der Frage, welcher Sozialisationsmuster dieser "Yuppie-Nazi" sich bedient, um vor allem Jugendliche zu faszinieren. Schließlich soll analysiert werden, wie der Regisseur durch eine postmoderne Inszenierung Auschwitz als Testgelände zur Verfügung stellt, auf dem der Neonazi einen "fröhlichen Tanz auf dem Vulkan" aufführen kann.
In meinem Beitrag stelle ich einige Besonderheiten und Probleme des Konzepts einer "ethnografischen Polizeiforschung" dar. Empirische Referenz ist eine ethnografische Untersuchung mehrerer Hessischer Polizeidienststellen im Jahr 1995. Die "teilnehmende Beobachtung des Gewaltmonopols" ist zwar nicht neu, nach wie vor aber in mehrfacher Hinsicht spannend, weil es sich um den Blick auf ein exklusives Gewaltverhältnis handelt, das zwar durch individuelle Akteure vollzogen wird, das aber strukturell auf die Kontextabhängigkeit der Handlung verweist: Gewalt ist nicht gleich Gewalt, die Staatsgewalt ist eine andere als der "Widerstand" gegen dieselbe. Diese Spannung, so die Ausgangsthese, findet sich auch in den Texten und Handlungen wieder, die von Polizisten tagtäglich habituell gestaltet werden. Die ethnografische Untersuchung der Polizei bezieht sich hauptsächlich auf Erzählungen von Polizisten und der Beobachtung ihres Alltags. Beschrieben wird, dass, im Gegensatz zu den offiziellen Bildern der Polizei (d.h. zur Polizeikultur), die sog. Handlungsmuster der Polizisten "auf der Straße" (diese nenne ich Polizistenkultur) sich im wesentlichen an einem informell tradierten Alltagspragmatismus orientieren, der häufig gekoppelt ist mit einer expressiven Bewerkstelligung von Männlichkeit.
Das Buch enthält einerseits eine Reihe von Fallstudien zu unterschiedlichen pädagogischen Fragen. Gemeinsam ist ihnen, dass qualitative Methoden angewandt werden, die Studierenden ermöglichen, eine "forschende Haltung" zu entwickeln. Andere Beiträge beschreiben die Bedingungen für eine Integration von wissenschaftlichen Methoden im Rahmen der Ausbildung von Lehrerinnen und Lehrern. Das Buch arbeitet keine Theorie auf, sondern zeigt, wie die Analyse empirisch erhobener Daten sinnvoll in der ersten Phase der Lehrerbildung zur Selbstreflexion der Studierenden beitragen kann. Die praktische Philosophie des Freiburger Verständnisses einer Interpretationswerkstatt kann Lehrende zur Arbeit mit Fallstudien ermuntern und Studierenden einen Einblick in die Möglichkeiten von Fallstudien bieten.
Wolfgang KÖHLER's Monographie über das Verstehen einer Person als eines Individuums ist ein Versuch, den in der Alltagssprache undifferenziert gebrauchten Begriff des Fremdverstehens sowie den des Selbstverstehens, wie er in Aussagen wie "Maria versteht ihren Mann" oder "Ich verstehe mich selbst nicht mehr" vorkommt, durch eine philosophische Reflexion zu differenzieren. Durch diese Reflexion wird gezeigt, dass der Verstehensbegriff auf drei verschiedene Weisen gebraucht wird: mit dem Anspruch eines Wissens, eines Könnens und eines Fühlens. Es ergibt sich, dass das Verstehen der eigenen wie der fremden Person im Sinne eines Wissens eine Ausnahme bildet, zumal dieses Wissen in einer mehr oder weniger poetischen Beschreibung darzustellen ist. Der Normalfall des Verstehens einer Person als eines unverwechselbaren Individuums besteht dagegen in einem Können oder Fühlen – und verdient damit gar nicht, ein "Verstehen" genannt zu werden im Sinne eines Wissens, wer jemand und wer man selbst ist. Das Buch erlaubt es, kritisch zu prüfen, welche hohen Ansprüche an die Versuche zu stellen sind, andere Personen, aber auch sich selbst zu verstehen. KÖHLER bleibt dabei eng an seinem lebensweltlichen Gegenstand und klärt im besten Sinne über das Verstehen von Personen auf.
Quest and query: interpreting a biographical interview with a turkish woman laborer in Germany
(2003)
Hülya, a young woman who came to Germany from Turkey at the age of 17 in pursuit of a better life looks back at the age of 31. In her biographical query she relates her experiences to a social commentary on the hard and inhuman conditions of contract labor. At the same time she is critical of the common sense notions that suffering and social problems are the main consequences of labor migration. In our analytical query of "doing biographical analysis" we discuss how we interpreted Hülya's narrative and commentary in socio-historical context and also in relation to the discourse on migration from Turkey. We looked for terms to analyze agency and suffering within biographical accounts without giving priority to either of them. Referring to the analysis of another case and to the concept of "twofold perspectivity" we describe how both suffering and also pursuing one's potential are negotiated in biographical quests and queries.
Der Band versammelt heterogene Beiträge zur "Pädagogischen Forschung im Kontext von Ethnografie und Biografie", die ihren gemeinsamen Bezugspunkt in den Forschungswerkstätten an der Kasseler Universität haben. In der Rezension werden die 14 Artikel vor dem Hintergrund der Zielsetzung des Bandes dargestellt. Diese besteht darin, die Vielfalt von ethnografischen Zugängen zu pädagogischen Feldern entlang einer methodenreflexiven Präsentation von Forschungsergebnissen zu dokumentieren und damit einen Beitrag zur Methodendiskussion in der Erziehungswissenschaft zu leisten. Die meisten Einzelbeiträge legen ihre Forschungsergebnisse entsprechend methodenreflexiv dar, wobei sie sich jedoch sehr unterschiedlich und zum Teil auch eher vage auf Ethnografie ausrichten bzw. auf pädagogische Felder beziehen. Leider wird der Ertrag dieser Kompilation von teilweise disparaten Forschungszugängen von den Herausgebern nicht systematisiert, sodass – trotz interessanter Einzelbeiträge – das Potenzial des Bandes für die methodologische "Vergewisserungsarbeit" in der Erziehungswissenschaft nur wenig sichtbar wird. Vielmehr hinterlässt die Lektüre des Bandes insgesamt eher den Eindruck einer gewissen Beliebigkeit im Gebrauch des Begriffes "Ethnografie".
An den Rändern der Diskurse. Jenseits der Unterscheidung diskursiver und nicht-diskursiver Praktiken
(2007)
Wenn von und für Diskursanalytiker(innen) eine Preisfrage ausgesetzt werden würde, dann wäre wohl eine der ersten zu beantwortenden Fragen, was denn eine "nicht-diskursive Praktik" sei. Die Frage markiert gewissermaßen die Grenze des Diskurses, denn schon die Benennung lässt vermuten, dass "nicht-diskursive Praktiken" eben nicht mehr Diskurs sind. Dieses Problem des Nicht-Diskursiven und die verschiedenen Möglichkeiten, diesen Rand, diese Grenze zu denken, auf ihrem Grat zu gehen oder sie zu unterlaufen, möchten wir im Folgenden zunächst anhand der theoretisch-methodologischen Debatte und dann anhand einiger konkreter Interpretationen von Texten und Beobachtungen aus verschiedenen empirischen Forschungsprojekten diskutieren. Dabei orientieren wir uns an den denkbaren Grenzen des Diskurses – der Macht, der Alltagspraxis, dem Körper, dem Subjekt – und entfalten die These, dass die Unterscheidung von diskursiv und nicht-diskursiv gerade nicht geeignet ist, Klarheit in die Debatte zu bringen.
In der letzten Dekade hat sich die Diskursforschung im Anschluss an Michel FOUCAULT im deutschsprachigen Raum interdisziplinär beständig weiterentwickelt. Sie ist dabei, sich im Rahmen qualitativer Sozialforschung – wie auch an sprachwissenschaftlichen Verfahren orientiert – zu etablieren.
Auf der internationalen und interdisziplinären Tagung "Sprache – Macht – Wissen" vom 10.-12.Oktober 2007 in Augsburg wurde der aktuelle Stand von Diskurstheorie und -analyse eruiert und diskutiert. Der Tagungsessay soll einen Einblick in die derzeitige Diskussion geben. Wir zeichnen zunächst die Fragestellungen und Zielsetzungen der Tagung nach. Es folgt eine knappe Zusammenfassung der gehaltenen Vorträge. Im Laufe der Tagung kristallisierten sich verschiedene Schwerpunkte heraus, die wiederholt aufgegriffen und diskutiert wurden: das Verhältnis von Diskursanalyse und Kritik, das Verhältnis von Subjekt(ivität) und Diskurs, das Verhältnis von Macht, Diskurs und Dispositiv sowie das Verhältnis von Diskursanalyse und Visualität. Mit der Systematisierung dieser vier Punkte nehmen wir eine kritische Betrachtung der "Ergebnisse" der Tagung vor. Abschließend verweisen wir auf zwei aktuelle Netzwerkinitiativen zur interdisziplinären Diskursforschung, die während der Tagung vorgestellt wurden.
Das Buch "Qualitative Evaluation" zeigt Schritt für Schritt die Vorgehensweise und stellt damit in sehr anwendungsorientierter Form das Handwerkszeug für eine qualitative Evaluation zur Verfügung. So werden Lesende in die Lage versetzt, eine solche Evaluation auch bei geringen Vorkenntnissen durchzuführen, wobei damit das Risiko verbunden sein kann, dass bei der Interpretation der Befunde wichtige Voraussetzungen für das Gelingen einer qualitativen Studie wie Verwurzelung der Interpretation im tatsächlich aufgezeichneten Text vernachlässigt werden.
Basierend auf Erfahrungen in einem Forschungsprojekt mit iranischstämmigen Migranten geht der Beitrag der Frage nach, inwiefern sich die umfassend reglementierte und damit weitgehend fremdbestimmte Lebenssituation als Flüchtling im deutschen Asyl auf die biografische Selbstthematisierung in Forschungszusammenhängen auswirkt.
Unabhängig vom jeweiligen Forschungsgegenstand beeinflusst der Kontext der Interviewsituation und die darin zustande kommende Beziehung zwischen Forschenden und Beforschten grundsätzlich die Gestalt der biografischen Erzählung. Infolge der Machtprozeduren im "totalen Flüchtlingsraum", die mit institutionell weitreichenden Zugriffen auf die Biografien von Asylsuchenden verbunden sind, ließ sich in den untersuchten Interviews jedoch eine mehr oder weniger stark ausgeprägte Verschärfung des ohnehin vorhandenen Hierarchieverhältnisses beobachten. In Anbetracht der empirischen Beobachtungen wird für eine reflexive biografiewissenschaftliche Migrationsforschung plädiert, die die Machtverhältnisse im transnationalen Raum in ihren Auswirkungen auf den Forschungsprozess systematisch analysiert. Forschende und Beforschte sind dabei nicht lediglich in ihren kulturellen Differenzen zu betrachten, sondern darüber hinaus in ihren unterschiedlichen intersektionellen Positionierungen, die von weiteren Machtmomenten wie dem sozioökonomischen Status, der Nationalität, dem Geschlecht, der Sexualität usw. bestimmt werden.