12 research outputs found
Die historische KontinuitĂ€t der ArgumentationsfĂŒhrung in der Mittelschuldebatte Ăsterreichs
Diese Diplomarbeit hat die historische KontinuitĂ€t in der österreichischen Mittelschuldebatte zum Thema. Es werden Texte des Autors Richard Meister, welcher zur Zeit der Ersten Republik ein fĂŒhrender Gegner des damaligen Gesamtschulversuchs war, analysiert und untersucht inwiefern BezĂŒge zu wissenschaftlichen und gewerkschaftlichen Zeitschriften, welche sich an der aktuellen Debatte rund um die EinfĂŒhrung einer Gesamtschule beteiligen, hergestellt werden können. Als Methode wird die diskurshistorische Analyse in Anlehnung an Matthias Jung (2001) und Achim Landwehr (2008) angewendet. Diese Forschungsmethode macht es möglich umfangreiche Textmengen zu bearbeiten und argumentative ZusammenhĂ€nge ĂŒber groĂe ZeitrĂ€ume hinweg zu identifizieren. Um die isolierten Argumente der unterschiedlichen AutorInnen vergleichbar zu machen und mögliche historische KontinuitĂ€ten aufzeigen zu können, wurden in Anlehnung an Herbert Gudjons (2008) vier Kategorien gebildet. Diese sind: pĂ€dagogisch-psychologische Argumente,
bildungsökonomische Argumente, bildungstheoretische Argumente sowie bildungspolitische Argumente. Anhand dieser Kategorien ist es möglich mögliche BezĂŒge zwischen Richard Meister und den AutorInnen der relevanten wissenschaftlichen/ gewerkschaftlichen Artikel innerhalb der Kategorien zu identifizieren und andererseits ist es durch eine Metaanalyse möglich, Kategorien ĂŒbergreifende BezĂŒge herauszuarbeiten. Auf dieser Grundlage wird es möglich, aufzuzeigen inwiefern BezĂŒge hinsichtlich der ArgumentationsfĂŒhrung zwischen Richard Meister und den AutorInnen der relevanten Artikel herausgearbeitet werden können
Critical care management of major hydrofluoric acid burns: a case report, review of the literature, and recommendations for therapy
Interface Properties of Organic <i>para</i>-Hexaphenyl/α-Sexithiophene Heterostructures Deposited on Highly Oriented Pyrolytic Graphite
It
was recently reported, that heterostructures of <i>para</i>-hexaphenyl (p-6P) and α-sexithiophene (6T) deposited on muscovite
mica exhibit the intriguing possibility to prepare lasing nanofibers
of tunable emission wavelength. For p-6P/6T heterostructures, two
different types of 6T emission have been observed, namely, the well-known
red emission of bulk 6T crystals and additionally a green emission
connected to the interface between p-6P and 6T. In this study, the
origin of the green fluorescence is investigated by photoelectron
spectroscopy (PES). As a prerequisite, it is necessary to prepare
structurally similar organic crystals on a conductive surface, which
leads to the choice of highly oriented pyrolytic graphite (HOPG) as
a substrate. The similarity between p-6P/6T heterostructures on muscovite
mica and on HOPG is evidenced by X-ray diffraction (XRD), scanning
force microscopy (SFM), and optical spectroscopy. PES measurements
show that the interface between p-6P and 6T crystals is sharp on a
molecular level without any sign of interface dipole formation or
chemical interaction between the molecules. We therefore conclude
that the different emission colors of the two 6T phases are caused
by different types of molecular aggregation
Epitaxy of Rodlike Organic Molecules on Sheet SilicatesîžA Growth Model Based on Experiments and Simulations
During the last years, self-assembled organic nanostructures have been recognized as a proper fundament for several electrical and optical applications. In particular, phenylenes deposited on muscovite mica have turned out to be an outstanding material combination. They tend to align parallel to each other forming needlelike structures. In that way, they provide the key for macroscopic highly polarized emission, waveguiding, and lasing. The resulting anisotropy has been interpreted so far by an induced dipole originating from the muscovite mica substrate. Based on a combined experimental and theoretical approach, we present an alternative growth model being able to explain molecular adsorption on sheet silicates in terms of moleculeâsurface interactions only. By a comprehensive comparison between experiments and simulations, we demonstrate that geometrical changes in the substrate surface or molecule lead to different molecular adsorption geometries and needle directions which can be predicted by our growth model
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Deciphering the molecular landscape and the tumor microenvironment of perivascular epitheloid cell neoplasma (PEComa)
11539
Background: PEComa is a rare mesenchymal neoplasm composed of perivascular epithelioid cells. Due to its rarity, diagnosis is challenging and no standardized treatment guidelines have been established. A subgroup of PEComas are characterized by a loss of function mutation in TSC1/2 that activates the PIK3-Akt-mTOR pathway. In the majority of patients, however, the molecular landscape and the composition of the tumor microenvironment (TME) remain largely unclear. Thus, we conducted this study to elucidate the genetic landscape of PEComas. A comparative analysis was performed with melanoma as a representative immunogenic tumor type. Methods: Thirty-five PEComa specimens were centrally analysed at the Caris Life Sciences laboratory. NextGen DNA sequencing (NextSeq, 592 gene panel or NovaSeq, whole-exome-sequencing), whole-transcriptome RNA sequencing (NovaSeq) and immunohistochemistry (Caris Life Sciences, Phoenix, AZ) were performed. Gene expression profiling (GEP) was performed by unsupervised hierarchical clustering. RNA deconvolution analysis was performed using the Microenvironment Cell Populations (MCP)-counter method to quantify immune cell populations (Becht 2016, Genome Biology). Results: The most common mutations detected in this cohort were TP53 (47%), ATRX (32%), TSC1/2 (11%/29%) and MSH3 (17%). Interestingly, TP53 mutations occurred less frequently (25 vs 60%, p = 0.055) in TSC1/2-mutated ( TSC1/2-mt) compared to TSC1/2-wildtype ( TSC1/2-wt) tumors, whereas MSH3 (25%, n = 1/4) and ERCC2 (14%, n = 2/14) mutations were exclusively observed in TSC1/2-mt cases. TSC1/2 mutations and other mTOR signalling pathway alterations, including two TFE gene fusion transcripts, were mutually exclusive. Of note, we found that 33.3% (n = 2) of TSC2-mt tumors were associated with high PIK3-Akt-mTOR pathway expression, while 100% (n = 3) of TSC1-mt tumors demonstrated lower expression. Deficient mismatch repair/microsatellite instability-high and high tumor mutational burden were rare (2.9%, n = 1 each) and observed concurrently in absence of PD-L1 expression. Overall, PD-L1 expression was observed in 21.9% (n = 7) of patients. An exploratory comparison with melanoma revealed that PEComa TMEs were characterized by a significant increase of NK cells and fibroblasts, as well as a relevant decrease of CD8
+
T cells and B cells. Conclusions: Within this study we discovered a heterogeneous molecular landscape with a high prevalence of TSC1/2 mutations that were in part associated with transcriptional up-regulation of the PIK3-Akt-mTOR pathway. Furthermore, the relatively immune-cold TME compared to melanoma suggests increased lymphocyte infiltration may be required to increase the efficacy of immune checkpoint inhibitors for PEComa
Color Tuning of Nanofibers by Periodic OrganicâOrganic Hetero-Epitaxy
We report on the epitaxial growth of periodic para-hexaphenyl (<i>p</i>-6P)/α-sexi-thiophene (6T) multilayer heterostructures on top of <i>p</i>-6P nanotemplates. By the chosen approach, 6T molecules are forced to align parallel to the <i>p</i>-6P template molecules, which yields highly polarized photoluminescence (PL)-emission of both species. The PL spectra show that the fabricated multilayer structures provide optical emission from two different 6T phases, interfacial 6T molecules, and 3-dimensional crystallites. By a periodical deposition of 6T monolayers and <i>p</i>-6P spacers it is demonstrated that the strongly polarized spectral contribution of interfacial 6T can be precisely controlled and amplified. By analyzing the PL emission of both 6T phases as a function of <i>p</i>-6P spacer thickness (Î<i>d</i><sub><i>p</i>â6P</sub>) we have determined a critical value of Î<i>d</i><sub><i>p</i>â6P </sub>â 2.73 nm where interfacial 6T runs into saturation and the surplus of 6T starts to cluster in 3-dimensional crystallites. These results are further substantiated by UPS and XRD measurements. Moreover, it is demonstrated by morphological investigations, provided by scanning force microscopy and fluorescence microscopy, that periodical deposition of 6T and <i>p</i>-6P leads to a significant improvement of homogeneity in PL-emission and morphology of nanofibers. Photoluminescence excitation experiments in combination with time-resolved photoluminescence demonstrate that the spectral emission of the organic multilayer nanofibers is dominated by a resonant energy transfer from <i>p</i>-6P host- to 6T guest-molecules. The sensitization time of the 6T emission in the 6T/<i>p</i>-6P multilayer structures depends on the <i>p</i>-6P spacer thickness, and can be explained by well separated layers of hostâguest molecules obtained by organicâorganic heteroepitaxy. The spectral emission and consequently the fluorescent color of the nanofibers can be efficiently tuned from the blue <i>via</i> white to the yellow-green spectral range