1830 search hits
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The mitochondrial kinase PINK1, stress response and Parkinson’s disease
(2009)
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Marina Jendrach
Suzana Gispert
Filomena Ricciardi
Michael Klinkenberg
Rudolf Schemm
Georg Auburger
- Mitochondrial dysfunction is well documented in presymptomatic brain tissue with Parkinson's disease (PD). Identification of the autosomal recessive variant PARK6 caused by loss-of-function mutations in the mitochondrial kinase PINK1 provides an opportunity to dissect pathogenesis. Although PARK6 shows clinical differences to PD, the induction of alpha-synuclein "Lewy" pathology by PINK1-deficiency proves that mitochondrial pathomechanisms are relevant for old-age PD. Mitochondrial dysfunction is induced by PINK1 deficiency even in peripheral tissues unaffected by disease, consistent with the ubiquitous expression of PINK1. It remains unclear whether this dysfunction is due to PINK1-mediated phosphorylation of proteins inside or outside mitochondria. Although PINK1 deficiency affects the mitochondrial fission/fusion balance, cell stress is required in mammals to alter mitochondrial dynamics and provoke apoptosis. Clearance of damaged mitochondria depends on pathways including PINK1 and Parkin and is critical for postmitotic neurons with high energy demand and cumulative stress, providing a mechanistic concept for the tissue specificity of disease.
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Über die normativen Implikationen des Ordoliberalismus für die moderne Wirtschaftsethik
(2009)
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Rainer Klump
Manuel Wörsdörfer
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Völkerrecht und Weltwirtschaft im 19. Jahrhundert. Die Internationalisierung der Ökonomie aus völkerrechts- und wirtschafts(theorie-)geschichtlicher Perspektive
(2009)
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Manuel Wörsdörfer
- Tagungsbericht des Workshops "Völkerrecht und Weltwirtschaft im 19. Jahrhundert. Die Internationalisierung der Ökonomie aus völkerrechts- und wirtschafts(theorie-)geschichtlicher Perspektive", der vom 3. bis 4. September 2009 in Frankfurt am Main stattfand. Veranstalter: Exzellenzcluster "Die Herausbildung normativer Ordnungen"; in Kooperation mit der Goethe Universität Frankfurt am Main; dem Max-Planck-Institut für europäische Rechtsgeschichte
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Treebank-based grammar acquisition for German
(2009)
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Ines Rehbein
- Manual development of deep linguistic resources is time-consuming and costly and therefore often described as a bottleneck for traditional rule-based NLP. In my PhD thesis I present a treebank-based method for the automatic acquisition of LFG resources for German. The method automatically creates deep and rich linguistic presentations from labelled data (treebanks) and can be applied to large data sets. My research is based on and substantially extends previous work on automatically acquiring wide-coverage, deep, constraint-based grammatical resources from the English Penn-II treebank (Cahill et al.,2002; Burke et al., 2004; Cahill, 2004). Best results for English show a dependency f-score of 82.73% (Cahill et al., 2008) against the PARC 700 dependency bank, outperforming the best hand-crafted grammar of Kaplan et al. (2004). Preliminary work has been carried out to test the approach on languages other than English, providing proof of concept for the applicability of the method (Cahill et al., 2003; Cahill, 2004; Cahill et al., 2005). While first results have been promising, a number of important research questions have been raised. The original approach presented first in Cahill et al. (2002) is strongly tailored to English and the datastructures provided by the Penn-II treebank (Marcus et al., 1993). English is configurational and rather poor in inflectional forms. German, by contrast, features semi-free word order and a much richer morphology. Furthermore, treebanks for German differ considerably from the Penn-II treebank as regards data structures and encoding schemes underlying the grammar acquisition task. In my thesis I examine the impact of language-specific properties of German as well as linguistically motivated treebank design decisions on PCFG parsing and LFG grammar acquisition. I present experiments investigating the influence of treebank design on PCFG parsing and show which type of representations are useful for the PCFG and LFG grammar acquisition tasks. Furthermore, I present a novel approach to cross-treebank comparison, measuring the effect of controlled error insertion on treebank trees and parser output from different treebanks. I complement the cross-treebank comparison by providing a human evaluation using TePaCoC, a new testsuite for testing parser performance on complex grammatical constructions. Manual evaluation on TePaCoC data provides new insights on the impact of flat vs. hierarchical annotation schemes on data-driven parsing. I present treebank-based LFG acquisition methodologies for two German treebanks. An extensive evaluation along different dimensions complements the investigation and provides valuable insights for the future development of treebanks.
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Occurrence and temporal variations of TMDD in the river Rhine, Germany
(2009)
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Arlen A. Guedez
Stephan Frömmel
Peter Diehl
Wilhelm Püttmann
- Background, aim, and scope: The chemical substance 2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) is a non-ionic surfactant used as an industrial defoaming agent and in various other applications. Its commercial name is Surynol 104® and the related ethoxylates are also available as Surfynol® 420, 440, 465 and 485 which are characterized by different grades of ethoxylation of TMDD at both hydroxyl functional groups. TMDD and its ethoxylates offer several advantages in waterborne industrial applications in coatings, inks, adhesives as well as in paper industries. TMDD and its ethoxylates can be expected to reach the aquatic environment due its widespread use and its physico-chemical properties. TMDD has previously been detected in several rivers of Germany with concentrations up to 2.5 µg/L. In the United States, TMDD was also detected in drinking water. However, detailed studies about its presence and distribution in the aquatic environment have not been carried out so far. The aim of the present study was the analysis of the spatial and temporal concentration variations of TMDD in the river Rhine at the Rheingütestation Worms (443.3 km). Moreover, the transported load in the Rhine was investigated during two entire days and 7 weeks between November 2007 and January 2008.
Materials and methods: The sampling was carried out at three different sampling points across the river. Sampling point MWL1 is located in the left part of the river, MWL2 in the middle part, and MWL4 in the right part. One more sampling site (MWL3) was run by the monitoring station until the end of 2006, but was put out of service due to financial constrains. The water at the left side of the river Rhine (MWL1) is influenced by sewage from a big chemical plant in Ludwigshafen and by the sewage water from this city. The water at the right side of the river Rhine (MWL4) is largely composed of the water inflow from river Neckar, discharging into Rhine 14.9 km upstream from the sampling point and of communal and industrial wastewater from the city Mannheim. The water from the middle of the river (MWL2) is largely composed of water from the upper Rhine. Water samples were collected in 1-L bottles by an automatic sampler. The water samples were concentrated by use of solid-phase extraction (SPE) using Bond Elut PPL cartridges and quantified by use of gas chromatography-mass spectrometry (GC-MS). The quantification was carried out with the internal standard method. Based on these results, concentration variations were determined for the day profiles and week profiles. The total number of analyzed samples was 219.
Results: The results of this study provide information on the temporal concentration variability of TMDD in river Rhine in a cross section at one particular sampling point (443.3 km). TMDD was detected in all analyzed water samples at high concentrations. The mean concentrations during the 2 days were 314 ng/L in MWL1, 246 ng/L in MWL2, and 286 ng/L in MWL4. The variation of concentrations was low in the day profiles. In the week profiles, a trend of increasing TMDD concentrations was detected particularly in January 2008, when TMDD concentrations reached values up to 1,330 ng/L in MWL1. The mean TMDD concentrations during the week profiles were 540 ng/L in MWL1, 484 ng/L in MWL2, and 576 ng/L in MWL4. The loads of TMDD were also determined and revealed to be comparable in all three sections of the river. The chemical plant located at the left side of the Rhine is not contributing additional TMDD to the river. The load of TMDD has been determined to be 62.8 kg/d on average during the entire period. By extrapolation of data obtained from seven week profiles the annual load was calculated to 23 t/a.
Discussion: The permanent high TMDD concentrations during the investigation period indicate an almost constant discharge of TMDD into the river. This observation argues for effluents of municipal wastewater treatment plants as the most likely source of TMDD in the river. Another possible source might be the degradation of ethoxylates of TMDD (Surfynol® series 400), in the WWTPs under formation of TMDD followed by discharge into the river. TMDD has to be considered as a high-production-volume (HPV) chemical based on the high concentrations found in this study. In the United States, TMDD is already in the list of HPV chemicals from the Environmental Protection Agency (EPA). However, the amount of TMDD production in Europe is unknown so far and also the biodegradation rates of TMDD in WWTPs have not been investigated.
Conclusions: TMDD was found in high concentrations during the entire sampling period in the Rhine river at the three sampling points. During the sampling period, TMDD concentrations remained constant in each part of the river. These results show that TMDD is uniformly distributed in the water collected at three sampling points located across the river. ‘Waves’ of exceptionally high concentrations of TMDD could not be detected during the sampling period. These results indicate that the effluents of WWTPs have to be considered as the most important sources of TMDD in river Rhine.
Recommendations and perspectives: Based also on the occurrence of TMDD in different surface waters of Germany with concentrations up to 2,500 ng/L and its presence in drinking water in the USA, more detailed investigations regarding its sources and distribution in the aquatic environment are required. Moreover, the knowledge with respect to its ecotoxicity and its biodegradation pathway is scarce and has to be gained in more detail. Further research is necessary to investigate the rate of elimination of TMDD in municipal and industrial wastewater treatment plants in order to clarify the degradation rate of TMDD and to determine to which extent effluents of WWTPs contribute to the input of TMDD into surface waters. Supplementary studies are needed to clarify whether the ethoxylates of TMDD (known as Surfynol 400® series) are hydrolyzed in the aquatic environment resulting in formation of TMDD similar to the well known cleavage of nonylphenol ethoxylates into nonylphenols. The stability of TMDD under anaerobic conditions in groundwater is also unknown and should be studied.
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Grimms Märchen und andere in oberhessischer Mundart von Laubach-Münster
(2009)
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Jürgen Piwowar
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Weitere auffällige Unterschiede in den mittelhessischen Mundarten zum Hochdeutschen
(2009)
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Jürgen Piwowar
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Ombre sul progresso : Forme del tempo e immagini del mondo nel pensiero di Ernst Bloch
(2009)
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Micaela Latini
- Tra le parole che si sono prestate agli usi più difformi e ambigui c'è sicuramente il concetto di progresso. Il motivo del "Fortschritt", che si è affermato nel XVIII secolo in contrapposizione alla visione ciclica propria dell'antichità, era associato all'idea di un incremento della produttività e alla prospettiva di uno sviluppo della storia umana. Questa deinizione positiva del progresso, per la quale al "dopo" corrisponde automaticamente il "meglio", sottende una concezione lineare della storia e rimanda a un modello tipicamente costruttivo. Ma il concetto di Fortschritt ha avuto una vita tutt'altro che pacifica: infatti ben presto si è affacciata prepotentemente sulla scena una visione ben diversa del progresso, che ha messo in crisi l'alone di gloria che sembrava accompagnarlo in dai suoi natali. In pochi luoghi è possibile misurare la crisi di questa gloriosa tradizione come nel capitalismo, dove l'ideologia dell'incremento quantitativo non ha portato ad alcun passo in avanti dal punto di vista qualitativo e in senso umano, ma piuttosto si è risolta in problemi globali e in dinamiche distruttive. Di fronte all'attestarsi di un progresso che è manifestazione di negatività, occorre mettere in guardia da un uso acritico della categoria del Fortschritt. È quanto sostiene Bloch in una conferenza tenuta nel 1955 e pubblicata l'anno successive con il titolo "Differenzierungen im Begriff Fortschritt". Come se non bastasse, sul fronte opposto c'è un'altra deriva da scongiurare: il problema che insorge sull'altro versante è quello di un totale rinnegamento del progresso. Si tratta di un errore teorico in cui molti sono caduti, e che segnala la necessità di una rilessione approfondita su questo tema. L'urgenza di interrogarsi sul "Was ist Fortschritt?" non deriva, per Bloch, dal fatto che il termine progresso sia di per sé poco chiaro e manifesto, ma semmai dal cattivo uso che ne è stato fatto Il primo passo da fare, secondo il programma blochiano di un recupero critico del "progresso", è quello di arginare gli intralci. Sono quei percorsi che sembrano condurre al Tiefenweg dell’Umano, e che invece si rivelano "vicoli ciechi" che non portano a nulla, o che sono costellati da botole che fanno ripiombare il viandante al punto di partenza. Da evitare sono inoltre quelle false piste che conducono in direzione contraria, nel senso opposto rispetto alla dimensione della Selbstbegegnung. Ciò che interessa a Bloch è denunciare le aporie contenute nel concetto stesso di "progresso", facendo afiorare quelle differenziazioni che lo rendono al contempo estremamente fragile ed ambiguo.
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L'avant-dernier mot : Notes sur Bloch et Jankélévitch à propos de "penser la mort"
(2009)
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Micaela Latini
- C'est dans une de ses analyses les plus suggestives du concept de mort que Lévinas suggère une comparaison entre la pensée de Bloch et celle de Jankélévitch. Et cela, comme l'on sait, bien que Jankélevitch, à l'exception de Schelling, n'ait jamais eu d'intérêt particulier pour la culture allemande et ses auteurs. Le point de départ de ces pages très denses, qu'on lit dans "Dieu, la mort et le temps" (1993), est la relation entre le thème de la mort et le projet que Bloch considère, à l'instar de Jankélevitch, comme la tâche irréalisable à laquelle, pourtant, on ne peut renoncer.
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Immagini in "Estinzione" : Memoria e fotografia in "Auslöschung" di Thomas Bernhard
(2009)
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Micaela Latini
- In un passo di Angelus Novus, Walter Benjamin ebbe a scrivere, citando Pascal : "'Nessuno', dice Pascal, 'muore così povero da non lasciare nulla in eredità'. Ciò vale anche per i ricordi – solo che essi non sempre trovano un erede". Per Thomas Bernhard può dichiararsi a buon titolo erede solo e proprio colui che si assume il compito di elaborare radicalmente il ricordo del passato, di estinguere una volta per tutte il radicamento all'origine. Nel romanzo Estinzione la memoria è condensata in una serie di immagini fotografiche che s'impongono, si sottopongono, si sovrappongono alla coscienza del protagonista, Franz Josef Murau. Sono la cifra del vincolo con l'origine, che qui è la cittadina austriaca di Wolfsegg: un cordone ombelicale che, attraverso il potere corrosivo del ricordo, deve essere reciso, fi bra dopo fi bra. E, per attendere a questo esito, occorre far cortocircuitare le varie visioni che investono la coscienza di Murau: immagini reali, immagini distorte, immagini sfigurate, immagini riflesse, immagini fotografiche, immagini memoriali, immagini sognate, immagini ideali, immagini dell'inconscio. È dalla lettura di una serie di Bilder che Murau attingerà il coraggio necessario per sobbarcarsi il peso di Wolfsegg, dell'origine che ci è toccata in sorte e che, proprio per questo, "delenda est".
