Study Circles to Enhance Program Growth in the New York City Adult Literacy World

The experiences of facilitators and participants in 4 study circles which focused on qualitative research points up individual, group, and systemic challenges and potential for educators in New York City literacy centers

Spatial proteomics revealed a CX3CL1-dependent crosstalk between the urothelium and relocated macrophages through IL-6 during an acute bacterial infection in the urinary bladder

The urothelium of the urinary bladder represents the first line of defense. However, uropathogenic E. coli (UPEC) damage the urothelium and cause acute bacterial infection. Here, we demonstrate the crosstalk between macrophages and the urothelium stimulating macrophage migration into the urothelium. Using spatial proteomics by MALDI-MSI and LC-MS/MS, a novel algorithm revealed the spatial activation and migration of macrophages. Analysis of the spatial proteome unravelled the coexpression of Myo9b and F4/80 in the infected urothelium, indicating that macrophages have entered the urothelium upon infection. Immunofluorescence microscopy additionally indicated that intraurothelial macrophages phagocytosed UPEC and eliminated neutrophils. Further analysis of the spatial proteome by MALDI-MSI showed strong expression of IL-6 in the urothelium and local inhibition of this molecule reduced macrophage migration into the urothelium and aggravated the infection. After IL-6 inhibition, the expression of matrix metalloproteinases and chemokines, such as CX3CL1 was reduced in the urothelium. Accordingly, macrophage migration into the urothelium was diminished in the absence of CX3CL1 signaling in Cx3cr1gfp/gfp mice. Conclusively, this study describes the crosstalk between the infected urothelium and macrophages through IL-6-induced CX3CL1 expression. Such crosstalk facilitates the relocation of macrophages into the urothelium and reduces bacterial burden in the urinary bladder. © 2020, The Author(s)

A multi-center study of their physicochemical characteristics, cell culture and in vivo experiments

PVP-capped silver nanoparticles with a diameter of the metallic core of 70 nm, a hydrodynamic diameter of 120 nm and a zeta potential of −20 mV were prepared and investigated with regard to their biological activity. This review summarizes the physicochemical properties (dissolution, protein adsorption, dispersability) of these nanoparticles and the cellular consequences of the exposure of a broad range of biological test systems to this defined type of silver nanoparticles. Silver nanoparticles dissolve in water in the presence of oxygen. In addition, in biological media (i.e., in the presence of proteins) the surface of silver nanoparticles is rapidly coated by a protein corona that influences their physicochemical and biological properties including cellular uptake. Silver nanoparticles are taken up by cell-type specific endocytosis pathways as demonstrated for hMSC, primary T-cells, primary monocytes, and astrocytes. A visualization of particles inside cells is possible by X-ray microscopy, fluorescence microscopy, and combined FIB/SEM analysis. By staining organelles, their localization inside the cell can be additionally determined. While primary brain astrocytes are shown to be fairly tolerant toward silver nanoparticles, silver nanoparticles induce the formation of DNA double-strand-breaks (DSB) and lead to chromosomal aberrations and sister-chromatid exchanges in Chinese hamster fibroblast cell lines (CHO9, K1, V79B). An exposure of rats to silver nanoparticles in vivo induced a moderate pulmonary toxicity, however, only at rather high concentrations. The same was found in precision-cut lung slices of rats in which silver nanoparticles remained mainly at the tissue surface. In a human 3D triple-cell culture model consisting of three cell types (alveolar epithelial cells, macrophages, and dendritic cells), adverse effects were also only found at high silver concentrations. The silver ions that are released from silver nanoparticles may be harmful to skin with disrupted barrier (e.g., wounds) and induce oxidative stress in skin cells (HaCaT). In conclusion, the data obtained on the effects of this well-defined type of silver nanoparticles on various biological systems clearly demonstrate that cell-type specific properties as well as experimental conditions determine the biocompatibility of and the cellular responses to an exposure with silver nanoparticles

Factors associated with worse lung function in cystic fibrosis patients with persistent staphylococcus aureus

Background Staphylococcus aureus is an important pathogen in cystic fibrosis (CF). However, it is not clear which factors are associated with worse lung function in patients with persistent S. aureus airway cultures. Our main hypothesis was that patients with high S. aureus density in their respiratory specimens would more likely experience worsening of their lung disease than patients with low bacterial loads. Methods Therefore, we conducted an observational prospective longitudinal multi-center study and assessed the association between lung function and S. aureus bacterial density in respiratory samples, co-infection with other CF-pathogens, nasal S. aureus carriage, clinical status, antibiotic therapy, IL-6- and IgG-levels against S. aureus virulence factors. Results 195 patients from 17 centers were followed; each patient had an average of 7 visits. Data were analyzed using descriptive statistics and generalized linear mixed models. Our main hypothesis was only supported for patients providing throat specimens indicating that patients with higher density experienced a steeper lung function decline (p<0.001). Patients with exacerbations (n = 60), S. aureus small-colony variants (SCVs, n = 84) and co-infection with Stenotrophomonas maltophilia (n = 44) had worse lung function (p = 0.0068; p = 0.0011; p = 0.0103). Patients with SCVs were older (p = 0.0066) and more often treated with trimethoprim/sulfamethoxazole (p = 0.0078). IL-6 levels positively correlated with decreased lung function (p<0.001), S. aureus density in sputa (p = 0.0016), SCVs (p = 0.0209), exacerbations (p = 0.0041) and co-infections with S. maltophilia (p = 0.0195) or A. fumigatus (p = 0.0496). Conclusions In CF-patients with chronic S. aureus cultures, independent risk factors for worse lung function are high bacterial density in throat cultures, exacerbations, elevated IL-6 levels, presence of S. aureus SCVs and co-infection with S. maltophilia

Exploring deep microbial life in coal-bearing sediment down to ~2.5 km below the ocean floor

Peer reviewedPostprin

Plasma Neurofilament Light for Prediction of Disease Progression in Familial Frontotemporal Lobar Degeneration

Objective: We tested the hypothesis that plasma neurofilament light chain (NfL) identifies asymptomatic carriers of familial frontotemporal lobar degeneration (FTLD)-causing mutations at risk of disease progression. Methods: Baseline plasma NfL concentrations were measured with single-molecule array in original (n = 277) and validation (n = 297) cohorts. C9orf72, GRN, and MAPT mutation carriers and noncarriers from the same families were classified by disease severity (asymptomatic, prodromal, and full phenotype) using the CDR Dementia Staging Instrument plus behavior and language domains from the National Alzheimer's Disease Coordinating Center FTLD module (CDR+NACC-FTLD). Linear mixed-effect models related NfL to clinical variables. Results: In both cohorts, baseline NfL was higher in asymptomatic mutation carriers who showed phenoconversion or disease progression compared to nonprogressors (original: 11.4 ± 7 pg/mL vs 6.7 ± 5 pg/mL, p = 0.002; validation: 14.1 ± 12 pg/mL vs 8.7 ± 6 pg/mL, p = 0.035). Plasma NfL discriminated symptomatic from asymptomatic mutation carriers or those with prodromal disease (original cutoff: 13.6 pg/mL, 87.5% sensitivity, 82.7% specificity; validation cutoff: 19.8 pg/mL, 87.4% sensitivity, 84.3% specificity). Higher baseline NfL correlated with worse longitudinal CDR+NACC-FTLD sum of boxes scores, neuropsychological function, and atrophy, regardless of genotype or disease severity, including asymptomatic mutation carriers. Conclusions: Plasma NfL identifies asymptomatic carriers of FTLD-causing mutations at short-term risk of disease progression and is a potential tool to select participants for prevention clinical trials. Trial registration information: ClinicalTrials.gov Identifier: NCT02372773 and NCT02365922. Classification of evidence: This study provides Class I evidence that in carriers of FTLD-causing mutations, elevation of plasma NfL predicts short-term risk of clinical progression

Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

Struktur der Lithosphäre und des oberen Erdmantels unter dem westlichen Böhmischen Massiv, abgeleitet aus P und S Receiver Functions

Title, Abstract, Contents, List of Figures, List of Tables 1\. Geological and tectonic setting 1 1.1 Regional overview 1 1.2 Geological setting of the western Bohemian Massif 3 1.2.1 Variscan structural units 3 1.2.2 Tectonomagmatic structures 5 2\. Results of previous geophysical, geochemical and petrological research 7 2.1 Seismicity of the Vogtland/NW-Bohemia swarm earthquake region 7 2.2 The crust and crust-mantle boundary in seismic studies 10 2.3 Lithospheric and upper mantle structure 12 2.4 CO2 emanations and fluid investigations 15 2.5 Xenolith investigations 16 2.6 Thermal structure 16 2.7 Further models of the investigation area 17 3\. Data 19 3.1 The passive seismic experiment BOHEMA 19 3.2 Data set for P receiver function analysis 21 3.3 Data set for S receiver function analysis 22 4\. Methods 23 4.1 P receiver function method 23 4.2 S receiver function method 25 5\. Moho depths and crustal vp/vs ratios 29 5.1 Nature of the Moho 29 5.2 Data examples 29 5.3 Observations 29 5.3.1 Ps delay times of the Moho discontinuity 29 5.3.2 Crustal vp/vs ratios 36 5.4 Discussion 38 5.4.1 Map of crustal vp/vs ratios 38 5.4.2 Depth map of the Moho discontinuity 42 5.4.3 Comparison with seismic refraction profile CEL09 45 6\. Structure and thickness of the lithospheric mantle 47 6.1 Nature of the lithosphere and lithosphere-asthenosphere transition 47 6.2 Additional phases observed in P receiver function data 49 6.3 Discussion: Structures within the lithospheric mantle 50 6.4 Observations in S receiver function data 54 6.4.1 S receiver functions obtained at the seismic stations 54 6.4.2 Dividing the data into local "boxes" 56 6.5 Discussion 60 6.5.1 Lithospheric thickness beneath the western Bohemian Massif 60 6.5.2 N-S and E-W profiles 63 7\. Discontinuities of the mantle transition zone 71 7.1 Nature of the mantle transition zone 71 7.2 Observation of the upper mantle discontinuities in the study area 73 7.3 Discussion 78 8\. Summary and Conclusions 85 8.1 Moho depths and crustal vp/vs ratios beneath the western Bohemian Massif 85 8.2 Structure and thickness of the lithospheric mantle 88 8.3 Upper mantle discontinuities at 410 and 660 km depth 90 8.4 Model of the lithosphere and upper mantle beneath the western Bohemian Massif 91 8.5 Open questions/ Outlook 93 Acknowledgements 97 References 99 Appendices 111 A.1 Station parameters of the BOHEMA experiment 111 A.2 Station parameters of the experiment by Geissler et al. 114 A.3 Members of the BOHEMA working group 115 B.1 Teleseismic events used for P receiver function analysis (BOHEMA stations) 116 B.2 Teleseismic events used for P receiver function analysis (stations by Geissler et al., 2005) 121 B.3 Teleseismic events used for S receiver function analysis 135 C.1 Moho depths and vp/vs ratios (Zhu and Kanamori method) 140 C.2 Moho depths and vp/vs ratios from Ps and PpPs 146 Title, Abstract, Contents, List of Figures, List of Tables 1\. Geological and tectonic setting 1 1.1 Regional overview 1 1.2 Geological setting of the western Bohemian Massif 3 1.2.1 Variscan structural units 3 1.2.2 Tectonomagmatic structures 5 2\. Results of previous geophysical, geochemical and petrological research 7 2.1 Seismicity of the Vogtland/NW-Bohemia swarm earthquake region 7 2.2 The crust and crust-mantle boundary in seismic studies 10 2.3 Lithospheric and upper mantle structure 12 2.4 CO2 emanations and fluid investigations 15 2.5 Xenolith investigations 16 2.6 Thermal structure 16 2.7 Further models of the investigation area 17 3\. Data 19 3.1 The passive seismic experiment BOHEMA 19 3.2 Data set for P receiver function analysis 21 3.3 Data set for S receiver function analysis 22 4\. Methods 23 4.1 P receiver function method 23 4.2 S receiver function method 25 5\. Moho depths and crustal vp/vs ratios 29 5.1 Nature of the Moho 29 5.2 Data examples 29 5.3 Observations 29 5.3.1 Ps delay times of the Moho discontinuity 29 5.3.2 Crustal vp/vs ratios 36 5.4 Discussion 38 5.4.1 Map of crustal vp/vs ratios 38 5.4.2 Depth map of the Moho discontinuity 42 5.4.3 Comparison with seismic refraction profile CEL09 45 6\. Structure and thickness of the lithospheric mantle 47 6.1 Nature of the lithosphere and lithosphere-asthenosphere transition 47 6.2 Additional phases observed in P receiver function data 49 6.3 Discussion: Structures within the lithospheric mantle 50 6.4 Observations in S receiver function data 54 6.4.1 S receiver functions obtained at the seismic stations 54 6.4.2 Dividing the data into local "boxes" 56 6.5 Discussion 60 6.5.1 Lithospheric thickness beneath the western Bohemian Massif 60 6.5.2 N-S and E-W profiles 63 7\. Discontinuities of the mantle transition zone 71 7.1 Nature of the mantle transition zone 71 7.2 Observation of the upper mantle discontinuities in the study area 73 7.3 Discussion 78 8\. Summary and Conclusions 85 8.1 Moho depths and crustal vp/vs ratios beneath the western Bohemian Massif 85 8.2 Structure and thickness of the lithospheric mantle 88 8.3 Upper mantle discontinuities at 410 and 660 km depth 90 8.4 Model of the lithosphere and upper mantle beneath the western Bohemian Massif 91 8.5 Open questions/ Outlook 93 Erklärung 147The Bohemian Massif is the largest coherent surface outcrop of the Variscan basement in central Europe. The investigation area of this study, the western Bohemian Massif, is situated at the junction of three Variscan structural units: the Saxothuringian in the north, the Teplá-Barrandian and Moldanubian units in the south. The Palaeozoic suture between the Saxothuringian and Teplá-Barrandian/Moldanubian units has been reactivated since the Upper Cretaceous/Tertiary as part of the European Cenozoic Rift System. This led to the evolution of the 300 km long and 50 km wide ENE-WSW trending Eger (Ohře) Rift. The western part of the Eger Rift is known for geophysical and geological phenomena such as the occurrence of earthquake swarms, CO2 dominated free gas emanations of subcontinental lithospheric mantle signature in mineral springs and mofettes, Tertiary/Quaternary volcanism and neotectonic crustal movements. To explain the observed phenomena, several possible scenarios have been suggested: a small-scale mantle plume, lithospheric thinning beneath the Eger Rift, and presently ongoing magmatic processes near the crust-mantle boundary, including magmatic underplating. This thesis focuses on the seismic structure of the lithosphere and upper mantle beneath the western Eger Rift area with the aim of investigating deep-lying possible causes of the phenomena observed at surface. For the investigation, data of the international passive seismic experiment BOHEMA carried out in 2002/2003 was used. The BOHEMA network consisted of 61 permanent and 84 temporary stations and was centred on the western Eger Rift. The resulting large data set allowed a high resolution P and S receiver function study using P-to-S and S-to-P converted waves, respectively, to map seismic discontinuities in the lithosphere and upper mantle. Data from an earlier passive seismic experiment was additionally used to complement the BOHEMA data set. The results of the analysis are described in this thesis from top to bottom . A high resolution Moho depth map of the investigated area could be obtained from more than 5000 P receiver function traces. It shows crustal thicknesses of 27 to 31 km in the Saxothuringian unit, 30 to 33 km in the Teplá-Barrandian and 34 to 39 km in the Moldanubian unit east of the Bavarian Shear Zone, which generally agrees with earlier results from seismic studies. A dominant feature in the Moho depth map is an area of thin crust of about 26 to 28 km beneath the western Eger Rift with irregular internal geometry. This apparent Moho updoming was already observed with less resolution in a previous receiver function study. It corresponds well with the area of CO2 degassing fields, the region of earthquake swarm occurrence and the location of Quaternary volcanoes at surface. The Moho depth values have an estimated uncertainty of ± 2 km. Furthermore, the first map of average crustal vp/vs ratios is presented for the investigated area. The mean values associated with structural units of the Variscan orogen vary between 1.69 and 1.75. For individual locations the variations are larger (between 1.66 and 1.81). In the area of Moho updoming and CO2 gas emanations, additional phases were observed in the P receiver function data: a positive phase at about 6 s delay time, followed by a strong negative phase at about 7 to 8 s. A mapping of the occurrence of these additional phases showed that they form a coherent structure centred on the western Eger Rift. The phases can be modelled by a discontinuity at 50 km suggested by results of seismic reflection and refraction investigations and a velocity decrease at 65 km depth. The velocity decrease might perhaps be explained by local asthenospheric updoming and/or a confined body of partial melt. S receiver functions were used to investigate the base of the lithosphere as a second, independent method. If the velocity reduction observed at 8 to 14 s delay time is interpreted as the lithosphere- asthenosphere transition, the data show lithospheric thickness of 80 to 90 km beneath the Saxothuringian and the northern Teplá-Barrandian unit. Towards the south, the thickness strongly increases in the Moldanubian unit to 115 to 135 km, which corresponds well with results of previous studies. The data of the transition from the thinner Saxothuringian/Teplá-Barrandian lithosphere to the thicker Moldanubian lithosphere show a doubling or broadening of the negative signal, which could point to either an abrupt increase of lithospheric thickness, or a very steep slope, or possibly even a structure from palaeosubduction within the lithosphere of this part of the investigated area. However, asthenospheric updoming beneath the contact of the Saxothuringian and Moldanubian units, centred beneath the western Eger Rift as suggested in P receiver function data, cannot be stated from S receiver functions. Two scenarios are suggested to explain the occurrence of the negative phase in the P and S receiver functions at different depths: (1) The negative phases in the P and S receiver functions represent two distinct velocity reductions. A thin low velocity layer is detected by P receiver functions in the lithospheric mantle at approximately 65 km depth that cannot be resolved by S receiver functions. The velocity reduction observed in S receiver function data might be interpreted as the lithosphere-asthenosphere transition. (2) The negative phases in the P and S receiver functions represent in principle the same negative velocity gradient (the lithosphere-asthenosphere transition), but strongly influenced by the different frequency contents of the P and S waves and by the possible nature of the transition from high to low velocities with increasing depth. Both scenarios imply a thin region of strongly decreased seismic velocity at about 65 km depth which might be associated with the occurrence of partial melt in this depth range. The P-to-S converted waves from the discontinuities of the mantle transition zone at 410 and 660 km depth show slightly increased delay times compared to the IASP91 global reference model. However, the thickness of the mantle transition zone is not affected and thus points to normal temperatures in the mantle transition zone and increased vp/vs ratio somewhere in the upper mantle above the mantle transition zone. Furthermore, a coherent converted phase is observed in P receiver functions that might be attributed to the discontinuity at 520 km depth.Das Böhmische Massiv bildet das größte zusammenhängende Gebiet anstehenden variskischen Grundgebirges in Mitteleuropa. Das Untersuchungsgebiet dieser Arbeit, das westliche Böhmische Massiv, befindet sich an der Nahtstelle dreier variskischer Struktureinheiten: dem Saxothuringikum im Norden, und dem Teplá- Barrandium und Moldanubikum im Süden. Die paläozoische Sutur zwischen Saxothuringikum und Teplá-Barrandium/Moldanubikum wurde durch das Europäische Känozoische Riftsystem seit der Oberkreide/Tertiär reaktiviert. Dies führte zur Entstehung des 300 km langen und 50 km breiten, ENE-WSW streichenden Eger (Ohře) Rifts. Der westliche Teil des Eger Rifts ist bekannt für geologische und geophysikalische Phänomene wie das Auftreten von Erdbebenschwärmen, CO2-dominierte Gasaustritte aus Mineralquellen und Mofetten mit subkontinentaler lithosphärischer Mantelsignatur, tertiären/quartären Vulkanismus und neotektonische Krustenbewegungen. Um die beobachteten Phänomene zu erklären, wurden verschiedene Szenarien vorgeschlagen: ein kleinräumiger Mantelplume, verringerte Lithosphärenmächtigkeit unter dem Eger Rift und gegenwärtig aktive magmatische Prozesse nahe der Kruste-Mantel-Grenze einschliesslich magmatischem underplating. Die vorliegende Arbeit befasst sich mit der seismischen Struktur der Lithosphäre und des oberen Erdmantels unter dem westlichen Eger Rift. Ziel ist die Untersuchung möglicher tiefliegender Ursachen der an der Oberfläche beobachteten Phänomene. Dafür wurden Daten des internationalen passiven seismischen Experiments BOHEMA genutzt, welches 2002-2003 durchgeführt wurde. Das BOHEMA-Stationsnetz bestand aus 61 Permanent- und 84 Mobilstationen, die im und um das westliche Eger Rift zentriert lagen. Der daraus hervorgehende große Datensatz erlaubte eine hochauflösende P und S Receiver Function Analyse, um seismische Diskontinuitäten in der Lithosphäre und im oberen Erdmantel mittels P-zu-S bzw. S-zu-P konvertierter Wellen zu kartieren. Zur Ergänzung konnten Daten eines früheren passiven seismischen Experiments genutzt werden. Die Ergebnisse der Untersuchung werden in der vorliegenden Arbeit "von oben nach unten" beschrieben. Eine hoch aufgelöste Mohotiefen-Karte des Untersuchungsgebietes wurde aus der Bearbeitung von mehr als 5000 Einzelspuren abgeleitet. Sie zeigt im Saxothuringikum Krustenmächtigkeiten von 27 bis 31 km, im Teplá-Barrandium 30 bis 33 km, und im Moldanubikum östlich des Bayrischen Pfahls 34 bis 39 km. Das stimmt generell gut mit bisherigen Ergebnissen seismischer Untersuchungen überein. In der Mohotiefen-Karte fällt ein Bereich dünner Erdkruste (26 bis 28 km) unter dem westlichen Eger Rift mit asymmetrischer Struktur auf. Diese sich andeutende Mohoaufwölbung wurde bereits mit geringerer Auflösung in einer früheren Receiver Function Untersuchung beobachtet. Das Gebiet der Mohoaufwölbung stimmt gut mit dem Gebiet der CO2 Entgasungsfelder, Erdbebenschwärme und dem Auftreten zweier quartärer Vulkane an der Erdoberfläche überein. Die ermittelten Werte für die Mohotiefe haben eine Unsicherheit von ± 2 km. Des weiteren wurde die erste Karte durchschnittlicher krustaler vp/vs-Verhältnisse des Untersuchungsgebietes erstellt. Die Durchschnittswerte für Struktureinheiten des variskischen Orogens variieren zwischen 1,69 und 1,75, Einzelwerte variieren stärker (zwischen 1,66 und 1,81). Im Gebiet der Mohoaufwölbung und CO2 Gasaustritte wurden zusätzliche Phasen in den P Receiver Functions beobachtet: eine positive Phase bei etwa 6 s Verzögerungszeit, gefolgt von einer starken negativen Phase bei 7 bis 8 s Verzögerungszeit. Diese zusätzlichen Phasen treten in einem zusammenhängenden Bereich des Untersuchungs-gebietes auf, der sein Zentrum wiederum unter dem westlichen Eger Rift hat. Die Phasen können durch eine Diskontinuität in 50 km Tiefe, die in früheren seismischen Untersuchungen beobachtet wurde, und eine Geschwindigkeitsabnahme in 65 km Tiefe modelliert werden. Die Geschwindigkeitsabnahme könnte durch eine lokale Aufwölbung der Asthenosphäre und/oder das Auftreten partieller Schmelzen erklärt werden. Um die Dicke der Lithosphäre mit einer zweiten, unabhängigen Methode zu untersuchen, wurden S Receiver Functions analysiert. Dabei wurde bei 8 bis 14 s Verzögerungszeit eine Geschwindigkeitsreduktion beobachtet, die als Lithosphären- Asthenosphärengrenze interpretiert werden kann. Die Lithosphärenmächtigkeit beträgt demnach unter dem Saxothuringikum und dem nördlichen Teplá-Barrandium 80 bis 90 km. Nach Süden nimmt die Lithosphärenmächtigkeit stark zu und beträgt unter dem Moldanubikum 115 bis 135 km, was generell gut mit den Ergebnissen früherer Arbeiten übereinstimmt. Die Daten am Übergang von der dünneren Saxothuringischen/Teplá-Barrandischen zur dickeren Moldanubischen Lithosphäre zeigen eine Verdopplung bzw. Verbreiterung des negativen Signals. Das könnte entweder auf einen stufenartigen oder sehr steilen Anstieg der Lithosphärendicke oder möglicherweise auf eine Paläosubduktionsstruktur hinweisen. Allerdings konnte in den S Receiver Functions keine Aufwölbung der Asthenosphäre unter dem westlichen Eger Rift, wie sie in P Receiver Functions vermutet wurde, beobachtet werden. Zwei Szenarien könnten das beobachtete Auftreten einer negativen Phase in P und S Receiver Functions in unterschiedlichen Tiefen erklären: (1) Die negativen Phasen in P und S Receiver Functions bilden zwei unterschiedliche Geschwindigkeitsverringerungen ab. Eine dünne Niedriggeschwindigkeitsschicht in etwa 65 km Tiefe wird von den P Receiver Functions aufgelöst, während sie von S Receiver Functions nicht aufgelöst werden kann. Die Geschwindigkeitsverringerung, die in den S Receiver Functions abgebildet wird, wird dagegen als Lithosphären-Asthenosphärengrenze interpretiert. (2) Die negativen Phasen in P und S Receiver Functions bilden im Prinzip die gleiche Geschwindigkeitsverringerung ab (die Lithosphären- Asthenosphärengrenze), allerdings beeinflusst von den Eigenschaften dieser Zone und dem unterschiedlichen Frequenzgehalt von P- und S-Wellen. Auch in diesem Fall müsste es einen dünnen Bereich mit starkem negativen Geschwindigkeitsgradienten in 65 km Tiefe geben, in dem auch partielle Schmelzen auftreten könnten. Die P-zu-S konvertierten Wellen von den Diskontinuitäten der Mantelübergangszone in 410 und 660 km Tiefe zeigen leicht erhöhte Verzögerungszeiten im Vergleich zum IASP91 Standard-Erdmodell. Die Dicke der Mantelübergangszone ist allerdings unverändert und weist daher auf normale Temperaturen in der Mantelübergangszone und ein erhöhtes vp/vs Verhältnis in einer Schicht oberhalb der Mantelübergangszone hin. Weiterhin wurden Anzeichen für die Existenz einer Diskontinuität in 520 km Tiefe beobachtet

Lithospheric and upper mantle structure beneath the western Bohemian Massif obtained from teleseismic P and S receiver functions

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Leading the Band: The Role of the Instructor in Online Learning for Educators

Drawing from the online experiences of teachers across the United States who participated in online professional development courses, this article focuses on what educators/participants consider to be the roles and responsibilities of the online instructor. They see the online instructor as facilitator, model, planner, coach, and communicator. They describe how these roles are uniquely tuned in the online environment