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Schon zu Ende des 19. Jahrhunderts rückten alpine Brandopferplätze in das Bewusstsein der archäologischen Forschung. Ihr Bestand wuchs in den folgenden Jahrzehnten stetig an, so dass heute mehr als 100 solcher prähistorischen Kultorte, vor allem im ostalpinen Bereich, bekannt sind. Der urnenfelderzeitliche Brandopferplatz Altenstadt-Grütze, nördlich der Stadt Feldkirch im Vorarlber-ger Rheintal gelegen, wurde in den Jahren 1954, 1955 und 1957 vom damaligen Direktor des Vorarl-berger Landesmuseums Dr. Emil Vonbank ausgegraben, jedoch nie von ihm veröffentlicht. Die Fundstelle ist aus mehreren Gründen bemerkenswert: Sowohl die baulichen Strukturen, wie auch die Lage abseits der Gebirgshöhen in der weiten Schwemmebene des Rheintals, sind im Kontext alpiner Brandopferplätze einmalig. Das reiche Fundinventar besteht unter anderem aus mehreren Tausend Keramikfragmenten. Dabei handelt es sich zum größten Teil um Material der Urnenfelder-kultur, allerdings zeigt etwa ein Fünftel des Bestandes Merkmale der südalpinen Laugen-Melaun Kultur. Hinzu kommen über 40 bronzene Gegenstände und zahlreiche verbrannte Tierknochen sowie Pflanzen- und Speisereste, die einen detaillierten Einblick in die Opferpraxis des späten 2. Jahrtausends vor Christus ermöglichen.
Mehr als 50 Jahre nach Grabungsende liegen die Ergebnisse nun erstmals umfassend in publizierter Form vor.
In this paper, I discuss verb to noun conversion in French. The properties of the input verb and the output noun are presented and a formal representation is proposed using the SBCG framework. The use of such a formalism based on constraints and multiple inheritance highlights the difficulties in defining what exactly is a conversion rule. I propose that the different properties of the input verb and the output noun can be thought of as different dimensions of classification, which characterize the verb to noun conversion rule.
Based on the notion of a lexicon with default inheritance, I address the problem of how to provide a template for lexical representations that allows us to capture the relatedness between inflected word forms and canonically derived lexemes within a broadly realizational-inferential model of morphology. To achieve this we need to be able to represent a whole host of intermediate types of lexical relatedness that are much less frequently discussed in the literature. These include transpositions such as deverbal participles, in which a word's morphosyntactic class changes (e.g. verb ⇒ adjective) but no semantic predicate is added to the semantic representation and the derived word remains, in an important sense, a "form" of the base lexeme (e.g. the 'present participle form of the verb'). I propose a model in which morphological properties are inherited by default from syntactic properties and syntactic properties are inherited from semantic properties, such as ontological category (the Default Cascade). Relatedness is defined in terms of a Generalized Paradigm Function (perhaps in reality a relation), a generalization of the Paradigm Function of Paradigm Function Morphology (Stump 2001). The GPF has four components which deliver respectively specifications of a morphological form, syntactic properties, semantic representation and a lexemic index (LI) unique to each individuated lexeme in the lexicon. In principle, therefore, the same function delivers derived lexemes as inflected forms. In order to ensure that a newly derived lexeme of a distinct word class can be inflected I assume two additional principles. First, I assume an Inflectional Specifiability Principle, which states that the form component of the GPF (which defines inflected word forms of a lexeme) is dependent on the specification of the lexeme's morpholexical signature, a declaration of the properties that the lexeme is obliged to inflect for (defined by default on the basis of morpholexical class). I then propose a Category Erasure Principle, which states that 'lower' attributes are erased when the GPF introduces a non-trivial change to a 'higher' attribute (e.g. a change to the semantic representation entails erasure of syntactic and morphological information). The required information is then provided by the Default Cascade, unless overridden by specific declarations in the GPF. I show how this model can account for a variety of intermediate types of relatedness which cannot easily be treated as either inflection or derivation, and conclude with a detailed illustration of how the system applies to a particularly interesting type of transposition in the Samoyedic language Sel'kup, in which a noun is transposed to a similitudinal adjective whose form is in paradigmatic opposition to case-marked noun forms, and which is therefore a kind of inflection.
This paper primarily presents an analysis of nominal inflection in Hindi within the framework of Distributed Morphology (Halle & Marantz 1993, 1994 and Harley and Noyer 1999). Müller (2002, 2003, 2004) for German, Icelandic and Russian nouns respectively and Weisser (2006) for Croatian nouns have also used Distributed Morphology (henceforth DM) to analyze nominal inflectional morphology. This paper will discuss in detail the inflectional categories and inflectional classes, the morphological processes operating at syntax, the distribution of vocabulary items and the readjustment rules required to describe Hindi nominal inflection. Earlier studies on Hindi inflectional morphology (Guru 1920, Vajpeyi 1958, Upreti 1964, etc.) were greatly influenced by the Paninian tradition (classical Sanskrit model) and work with Paninian constructs such as root and stem. They only provide descriptive studies of Hindi nouns and verbs and their inflections without discussing the role or status of affixes that take part in inflection. The discussion on the mechanisms (morphological operations and rules) used to analyze or generate word forms are missing in these studies. In addition, these studies do not account for syntax-morphology or morphology-phonology mismatches that show up in word formation. One aim of this paper is to present an economical way of forming noun classes in Hindi as compared to other traditional methods, especially gender and stem ending based or paradigm based methods that give rise to a large number of inflectional paradigms. Using inflectional class information to analyse the various forms of Hindi nouns, we can reduce the number of affixes and word-generation and readjustment rules that are required to describe nominal inflection. The analysis also helps us in developing a morphological analyzer for Hindi. The small set of rules and fewer inflectional classes are of great help to lexicographers and system developers. To the best of our knowledge, the analysis of Hindi inflectional morphology based on DM and its implementation in a Hindi morphological analyzer has not been done before. The methods discussed here can be applied to other Indian languages for analysis as well as word generation.
This paper presents a descriptive overview and formal analysis of the use of pronominal clitics for realizing various types of arguments in Persian, with particular emphasis on object clitics in the verbal domain. We argue that pronominal clitics behave more like suffixes than independent syntactic elements; in cases where they take syntactic scope over an NP or a PP, they must be phrasal affixes. We propose an HPSG analysis to account for the morphosyntactic aspects of verbal suffixation of object clitics, possessive clitics, preverbal object clitics, and clitic doubling constructions. Finally, we explore extensions of the analysis to periphrastic verb forms, and we compare our proposals for Persian to previous HPSG work on clitic phenomena in other languages.
In the Cognate Object Construction (COC) a typically intransitive verb combines with a postverbal noun phrase whose head noun is morphologically or semantically cognate to the verb. I will argue that English has a family of COCs which consists of four different types. The COCs share common core properties but differ with respect to some of their syntactic and semantic properties. I will capture the ''cognateness'' between the verb and the noun in all COCs by token identities at the level of their lexical semantic contribution. I will use an inheritance hierarchy on lexical rule sorts to model the family relations among the different COC types.
Mazatec is an Eastern Otomanguean language spoken by about 200,000 people, located in the northeastern part of the state of Oaxaca, Mexico. The present paper aims to shed new light on Mazatec verb inflection within the framework of current research on Otomanguean phonology and morphology. We intend to show that, despite bewildering apparent complexity, mainly due to extensive morphophonological processes, Mazatec inflectional morphology is in fact rather simple and regular. Realizational approaches, in particular Paradigm Function Morphology (PFM) seem especially adequate to capture such regularities.
Korean comparative constructions: A constraint-based approach and computational implementation
(2010)
The complexity of comparative constructions in each language has given challenges to both theoretical and computational analyses. This paper first identifies types of comparative constructions in Korean and discusses their main grammatical properties. It then builds a syntactic parser couched upon the typed feature structure grammar, HPSG and proposes a context-dependent interpretation for the comparison. To check the feasibility of the proposed analysis, we have implemented the grammar into the existing Korean Resource Grammar. The results show us that the grammar we have developed here is feasible enough to parse Korean comparative sentences and yield proper semantic representations though further development is needed for a finer model for contextual information.
Semitic languages exhibit rich nonconcatenative morphological operations, which can generate a myriad of derived lexemes. Especially, the feature rich, root-driven morphology in the Arabic language demonstrates the construction of several verb-derived nominals (verbal nouns) such as gerunds, active participles, passive participles, locative participles, etc. Although HPSG is a successful syntactic theory, it lacks the representation of complex nonconcatenative morphology. In this paper, we propose a novel HPSG representation for Arabic nominals and various verb-derived nouns. We also present the lexical type hierarchy and derivational rules for generating these verb-derived nominals using the HPSG framework.
Usage-based preferences in written sentence production: The role of local and global statistics
(2010)
In this paper, we will discuss the role of different levels of frequency distributions in sentence processing and in written production, looking at French homophones. A comparison of experimental data and corpus statistics will demonstrate that lexical frequencies as well as local and global coherences have to be taken into account to fully explain the empirically established patterns.
Investigating the morphological and syntactic properties of discontinuous negative marking in Hausa, I shall suggest a constructional approach involving edge inflection, accounting simultaneously for the morphologically bound nature of the initial marker and its interaction with the TAM system, haplology of the final marker, and wide scope over coordination. I will argue that the degree of morphological integration of initial markers and haplology of final markers both favour an edge feature approach over phrasal affixation.
There are fascinating problems at the syntax-morphology interface which tend to be missed. I offer a brief explanation of why that may be happening, then give a Canonical Typology perspective, which brings these problems to the fore. I give examples showing that the phenomena could in principle be treated either by syntactic rules (but these would be complex) or within morphology (but this would involve redundancy). Thus 'non-autonomous' case values, those which have no unique form but are realized by patterns of syncretism, could be handled by a rule of syntax (one with access to other features, such as number) or by morphology (with resulting systematic syncretisms). I concentrate on one of the most striking sets of data, the issue of prepositional government in Latvian, and outline a solution within Network Morphology using structured case values.
Coherence generally refers to a kind of predicate formation where a verb forms a complex predicate with the head of its infinitival complement. Adjectives taking infinitival complements have also been shown to allow coherence, but the exact conditions for coherence with adjectives appear not to have been addressed in the literature. Based on a corpus-study (supplemented with grammaticality judgements by native speakers) we show that adjectives fall into three semantically and syntactically defined classes correlating with their ability to construct coherently. Non-factive and non-gradable adjectives allow coherence, factive and gradable adjectives do not allow coherence and non-factive and gradable adjectives are tolerated with coherence. On the basis of previous work on coherence in German we argue that coherence allows the infinitival complement of a verb or an adjective to be "split-up", so that the head and a dependent of this head are associated with different information structural functions. In this respect coherence patterns with extraction structures where the extracted constituent has an information structural function different from the constituent from which it is extracted. Following literature on the information structural basis of extraction islands, we show how the lack of coherence with factive adjectives follows from their complements' being information structurally backgrounded, while the infinitival complements of non-factive adjectives tend to a higher fusion with the matrix clause. We also show that coherence is observed with attributive adjectives as well, arguing that coherence is not a distinct verbal property. Finally we provide an analysis of coherence with adjectives within HPSG.
This work focuses on the syntax and semantics of the expression vice versa, and shows that its syntactic distribution is much more flexible than semantically related expressions. Although vice versa usually appears in clausal coordinate environments, it can in principle occur in any other type of construction. Second, it can occur as an embedded verb phrase or even as a noun phrase, rather than as an adjunct. This suggests that vice versa is a propositional anaphor that corresponds to a converse of a propositional antecedent. Finally, although the predicates singled out to be interchanged are usually nominal, they can in fact be of virtually any part of speech. I argue that a possible account of the interpretation of vice versa lies at the interface between logical form (with rich decompositional lexical semantics along the lines of Pustejovsky (1995)), and pragmatics (drawing from independent work by Hobbs (1990) and Kehler (2002)).
We describe an empirical method to explore and contrast the roles of default and principal part information in the differentiation of inflectional classes. We use an unsupervised machine learning method to classify Russian nouns into inflectional classes, first with full paradigm information, and then with particular types of information removed. When we remove default information, shared across classes, we expect there to be little effect on the classification. In contrast when we remove principal part information we expect there to be a more detrimental effect on classification performance. Our data set consists of paradigm listings of the 80 most frequent Russian nouns, generated from a formal theory which allows us to distinguish default and principal part information. Our results show that removal of forms classified as principal parts has a more detrimental effect on the classification than removal of default information. However, we also find that there are differences within the defaults and principal parts, and we suggest that these may in part be attributable to stress patterns.
Welsh is a language in which unbounded dependency constructions involve both gaps and resumptive pronouns (RPs). Gaps and RPs appear in disjoint sets of environments. Otherwise, however, they are quite similar. This suggests that they involve the same mechanism, and in HPSG that they involve the SLASH feature. It is possible to provide an analysis in which RPs are associated with the SLASH feature but are also the ordinary pronouns which they appear to be.
This papers addresses information-structural restrictions on the occurrence of what is known as "multiple fronting" in German. Multiple fronting involves the realization of (what appears to be) more than one constituent in the first position of main clause declaratives, a clause type that otherwise respects the verb-second constraint of German. Relying on a large body of naturally occurring instances of multiple fronting with the surrounding discourse context, we show that in certain contexts, multiple fronting is fully grammatical in German, in contrast to what has sometimes been claimed previously. Examination of this data reveals two different patterns, which we analyze in terms of two distinct constructions, each instantiating a specific pairing of form, meaning and contextual appropriateness.
A little discussed feature of English are non-restrictive relative clauses in which the antecedent is normally not an NP and the gap follows an auxiliary, as in Kim will sing, which Lee won't. These relative clauses resemble clauses with auxiliary complement ellipsis or fronting. There are a variety of analyses that might be proposed, but there are reasons for thinking that the best analysis is one where which is a nominal filler associated with a gap which is generally non-nominal: a filler-gap mismatch analysis in other words.
This paper addresses the form-meaning relation of multimodal communicative actions by means of a grammar that combines verbal input with hand gestures. Unlike speech, gesture signals are interpretable only through their semantic relation to the synchronous speech content. This relation serves to resolve the incomplete meaning that is revealed by gestural form alone. We demonstrate that by using standard linguistic methods, speech and gesture can be integrated in a constrained way into a single derivation tree which maps to a uniform meaning representation.
Does chain hybridization in Irish support movement-based approaches to long-distance dependencies?
(2010)
Huybregts (2009) makes the claim that hybrid A'-chains in Irish favor derivational theories of syntax over representational ones such as HPSG. In this paper, we subject this assertion to closer scrutiny. Based on a new technical proposal, we will reach the conclusion that, in principle, both derivational and representational accounts can accomodate hybrid dependencies. Thus, no argument against either approach can be made on the basis of the Irish data, disconfirming Huybregts's (2009) claim.
For many services, consumers can choose among a range of optional tariffs that differ in their access and usage prices. Recent studies indicate that tariff-specific preferences may lead consumers to choose a tariff that does not minimize their expected billing rate. This study analyzes how tariff-specific preferences influence the responsiveness of consumers’ usage and tariff choice to changes in price. We show that consumer heterogeneity in tariff-specific preferences leads to heterogeneity in their sensitivity to price changes. Specifically, consumers with tariff-specific preferences are less sensitive to price increases of their preferred tariff than other consumers. Our results provide an additional reason why firms should offer multiple tariffs rather than a uniform nonlinear pricing plan to extract maximum consumer surplus.
Entzündliche Herzerkrankungen betreffen kombiniert oder isoliert den Herzmuskel und dessen Hülle. Endo-, Myo- und/oder Perikarditiden haben viele verschiedene Ursachen. Sie verlaufen als akute oder chronische Erkrankung. Neben Viren, die gegenwärtig als auslösende Agentien dominieren, sind weiterhin Bakterien, Pilze und Parasiten anzuführen. Autoimmunologische Prozesse sowie bestimmte Therapeutika, z.B. Cocain, gelten als Auslöser nicht infektiöser Myokarditiden. In 25% der Fälle findet sich bei bestehender Myokarditis eine Perikardbeteiligung. Nachfolgend sollen wichtige mikrobiologische Erreger und deren Nachweismöglichkeiten vorgestellt werden, die im Zusammenhang mit einer Myo- und/oder Perikarditis stehen.
In Europa zählen Viren zu den häufigsten Verursachern einer Myokarditis. Im Unterschied zur Perikarditis ist die Symptomatik der Myokarditis oft uncharakteristisch und erfordert den Einsatz von Laboruntersuchungen. Die Abklärung der Virusätiologie begnügt sich meist mit dem Nachweis einer zeitgleich ablaufenden Infektionskrankheit (Plausibilitätsdiagnose). Zur direkten Virusdetektion ist die Entnahme einer Herzbiopsie erforderlich. An diesem Material kann das Virus mittels immunhistologischer und molekularbiologischer Methoden unter gleichzeitiger Beurteilung des inflammatorischen Prozesses nachgewiesen werden. Der Einsatz der verschiedenen Untersuchungsmethoden richtet sich nach dem Kosten-Nutzen-Verhältnis.
Qualitative und quantitative serologische Verfahren können durch Interferenzen gestört sein. Wir konnten in einem exemplarischen Fall anhand des Influenza A/H1N1v-Hämagglutinationshemmtests (H1N1-HHT) zeigen, dass auch Hyposensibilisierungstherapie und Vakzination zu Interaktionen in der serologischen Diagnostik führen und die Aussagekraft des H1N1-HHT massiv beeinträchtigen. Vor dem Hintergrund, dass Hyposensibilisierung und Vakzination im Klinik- und Praxisalltag häufig erbrachte Leistungen darstellen, erscheint dieser Umstand berichtenswert.
Proteins of the Omp85 family are conserved in all kingdoms of life. They mediate protein transport across or protein insertion into membranes and reside in the outer membranes of Gram-negative bacteria, mitochondria, and chloroplasts. Omp85 proteins contain a C-terminal transmembrane β-barrel and a soluble N terminus with a varying number of polypeptide-transport-associated or POTRA domains. Here we investigate Omp85 from the cyanobacterium Anabaena sp. PCC 7120. The crystallographic three-dimensional structure of the N-terminal region shows three POTRA domains, here named P1 to P3 from the N terminus. Molecular dynamics simulations revealed a hinge between P1 and P2 but in contrast show that P2 and P3 are fixed in orientation. The P2-P3 arrangement is identical as seen for the POTRA domains from proteobacterial FhaC, suggesting this orientation is a conserved feature. Furthermore, we define interfaces for protein-protein interaction in P1 and P2. P3 possesses an extended loop unique to cyanobacteria and plantae, which influences pore properties as shown by deletion. It now becomes clear how variations in structure of individual POTRA domains, as well as the different number of POTRA domains with both rigid and flexible connections make the N termini of Omp85 proteins versatile adaptors for a plentitude of functions.
Moderately elevated levels of plasma plant sterols have been suspected to be causally involved in atherosclerosis. The aim of this study was to investigate whether plant sterols and other markers of sterol metabolism predicted all-cause and cardiovascular mortality in participants of the Ludwigshafen Risk and Cardiovascular health (LURIC) study. A total of 1,257 individuals who did not use statins and at baseline had a mean (± SD) age of 62.8 (± 11.0) years were included in the present analysis. Lathosterol, cholestanol, campesterol, and sitosterol were measured to estimate cholesterol synthesis and absorption. The mean (± SD) time of the follow-up for all-cause and cardiovascular mortality was 7.32 (± 2.3) years. All-cause (P = 0.001) and cardiovascular (P = 0.006) mortality were decreased in the highest versus the lowest lathosterol to cholesterol tertile. In contrast, subjects in the third cholestanol to cholesterol tertile had increased all-cause (P < 0.001) and cardiovascular mortality (P = 0.010) compared with individuals in the first tertile. The third campesterol to cholesterol tertile was associated with increased all-cause mortality (P = 0.025). Sitosterol to cholesterol tertiles were not significantly related to all-cause or cardiovascular mortality. The data suggest that high absorption and low synthesis of cholesterol predict increased all-cause and cardiovascular mortality in LURIC participants.
Chromalveolates are a diverse group of protists that include many ecologically and medically relevant organisms such as diatoms and apicomplexan parasites. They possess plastids generally surrounded by four membranes, which evolved by engulfment of a red alga. Today, most plastid proteins must be imported, but many aspects of protein import into complex plastids are still cryptic. In particular, how proteins cross the third outermost membrane has remained unexplained. We identified a protein in the third outermost membrane of the diatom Phaeodactylum tricornutum with properties comparable to those of the Omp85 family. We demonstrate that the targeting route of P. tricornutum Omp85 parallels that of the translocation channel of the outer envelope membrane of chloroplasts, Toc75. In addition, the electrophysiological properties are similar to those of the Omp85 proteins involved in protein translocation. This supports the hypothesis that P. tricornutum Omp85 is involved in precursor protein translocation, which would close a gap in the fundamental understanding of the evolutionary origin and function of protein import in secondary plastids.
The donor-free silanimines tBu2Si=N-SiRtBu2 (R = tBu, Ph), which are prepared from tBu2ClSiN3 and NaSiRtBu2 at −78 ◦C inBu2O, decompose in benzene at room temperature with the formation of isobutene. Products of ene reactions of isobutene and tBu2Si=N-SiRtBu2 (R = tBu, Ph) are formed. X-Ray quality crystals of H2C=C(CH2SitBu2-NH-SiPhtBu2)2 (monoclinic, space group C2/c, Z = 4) were grown from a benzene solution at ambient temperature, whereas single crystals of H2C=C(CH2SitBu2-NH-SitBu3)2 (monoclinic, space group P21, Z = 2) were obtained by recrystallization from THF.
The human immunodeficiency virus (HIV) protease inhibitor saquinavir shows anticancer activity. Although its nitric oxide-modified derivative saquinavir-NO (saq-NO) was less toxic to normal cells, it exerted stronger inhibition of B16 melanoma growth in syngeneic C57BL/6 mice than saquinavir did. Saq-NO has been shown to block proliferation, upregulate p53 expression, and promote differentiation of C6 glioma and B16 cells. The anticancer activity of substances is frequently hampered by cancer cell chemoresistance mechanisms. Therefore, we here investigated the roles of p53 and the ATP-binding cassette (ABC) transporters P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1), and breast cancer resistance protein 1 (BCRP1) in cancer cell sensitivity to saq-NO to get more information about the potential of saq-NO as anticancer drug. Saq-NO exerted anticancer effects in lower concentrations than saquinavir in a panel of human cancer cell lines. Neither p53 mutation or depletion nor expression of P-gp, MRP1, or BCRP1 affected anticancer activity of saq-NO or saquinavir. Moreover, saq-NO sensitized P-gp-, MRP1-, or BCRP1-expressing cancer cells to chemotherapy. Saq-NO induced enhanced sensitization of P-gp- or MRP1-expressing cancer cells to chemotherapy compared with saquinavir, whereas both substances similarly sensitized BCRP1-expressing cells. Washout kinetics and ABC transporter ATPase activities demonstrated that saq-NO is a substrate of P-gp as well as of MRP1. These data support the further investigation of saq-NO as an anticancer drug, especially in multidrug-resistant tumors.
Peroxisome proliferator-activated receptor γ (PPARγ) gained considerable interest as a therapeutic target during chronic inflammatory diseases. Remarkably, the pathogenesis of diseases such as multiple sclerosis or Alzheimer is associated with impaired PPARγ expression. Considering that regulation of PPARγ expression during inflammation is largely unknown, we were interested in elucidating underlying mechanisms. To this end, we initiated an inflammatory response by exposing primary human macrophages to lipopolysaccharide (LPS) and observed a rapid decline of PPARγ1 expression. Because promoter activities were not affected by LPS, we focused on mRNA stability and noticed a decreased mRNA half-life. As RNA stability is often regulated via 3′-untranslated regions (UTRs), we analyzed the impact of the PPARγ-3′-UTR by reporter assays using specific constructs. LPS significantly reduced luciferase activity of the pGL3-PPARγ-3′-UTR, suggesting that PPARγ1 mRNA is destabilized. Deletion or mutation of a potential microRNA-27a/b (miR-27a/b) binding site within the 3′-UTR restored luciferase activity. Moreover, inhibition of miR-27b, which was induced upon LPS exposure, partially reversed PPARγ1 mRNA decay, whereas miR-27b overexpression decreased PPARγ1 mRNA content. In addition, LPS further reduced this decay. The functional relevance of miR-27b-dependent PPARγ1 decrease was proven by inhibition or overexpression of miR-27b, which affected LPS-induced expression of the pro-inflammatory cytokines tumor necrosis factor α (TNFα) and interleukin (IL)-6. We provide evidence that LPS-induced miR-27b contributes to destabilization of PPARγ1 mRNA. Understanding molecular mechanisms decreasing PPARγ might help to better appreciate inflammatory diseases.
Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that are implicated in the regulation of lipid and glucose homeostasis. PPAR agonists have been shown to control inflammatory processes, in part by inhibiting distinct proinflammatory genes (e.g. Il-1β and IFN-γ). IL-8 is a member of the proinflammatory chemokine family that is important for various functions, such as mediating the adhesion of eosinophilic granulocytes onto endothelial cells. The influence of PPARδ activators on the expression of IL-8 in noninduced quiescent endothelial cells is unclear. Therefore, we explored the influence of PPARδ activators on the expression of IL-8 in nonstimulated endothelial cells. PPARδ agonists induce IL-8 expression in human umbilical vein endothelial cells. This induction is demonstrated at the level of both protein and mRNA expression. Transcriptional activation studies using IL-8 reporter gene constructs and DNA binding assays revealed that PPARδ agonists mediated their effects via an NFκB binding site. It is well known that IL-8 is also regulated by mRNA stability. To provide further evidence for this concept, we performed mRNA stability assays and found that PPARδ agonists induce the mRNA stability of IL-8. In addition, we showed that PPARδ agonists induce the phosphorylation of ERK1/2 and p38, which are known to be involved in the increase of mRNA stability. The inhibition of these MAPK signaling pathways resulted in a significant suppression of the induced IL-8 expression and the reduced mRNA stability. Therefore, our data provide the first evidence that PPARδ induces IL-8 expression in nonstimulated endothelial cells via transcriptional as well as posttranscriptional mechanisms.
Experience-dependent alterations in the human brain's white-matter microstructure occur in early adulthood, but it is unknown whether such plasticity extends throughout life. We used cognitive training, diffusion-tensor imaging (DTI), and structural MRI to investigate plasticity of the white-matter tracts that connect the left and right hemisphere of the frontal lobes. Over a period of about 180 days, 20 younger adults and 12 older adults trained for a total of one hundred and one 1-h sessions on a set of three working memory, three episodic memory, and six perceptual speed tasks. Control groups were assessed at pre- and post-test. Training affected several DTI metrics and increased the area of the anterior part of the corpus callosum. These alterations were of similar magnitude in younger and older adults. The findings indicate that experience-dependent plasticity of white-matter microstructure extends into old age and that disruptions of structural interhemispheric connectivity in old age, which are pronounced in aging, are modifiable by experience and amenable to treatment.
Human exposure to endocrine disruptors is well documented by biomonitoring data. However, this information is limited to few chemicals like bisphenol A or phthalate plasticizers. To account for so-far unidentified endocrine disruptors and potential mixture effects we employ bioassays to detect endocrine activity in foodstuff and consequently characterize the integrated exposure to endocrine active compounds. Recently, we reported a broad contamination of commercially available bottled water with estrogenic activity and presented evidence for the plastic packaging being a source of this contamination. In continuation of that work, we here compare different sample preparation methods to extract estrogen-like compounds from bottled water. These data demonstrate that inappropriate extraction methods and sample treatment may lead to false-negative results when testing water extracts in bioassays. Using an optimized sample preparation strategy, we furthermore present data on the estrogenic activity of bottled water from France, Germany, and Italy: eleven of the 18 analyzed water samples (61.1%) induced a significant estrogenic response in a bioassay employing a human carcinoma cell line (MCF7, E-Screen). The relative proliferative effects ranged from 19.8 to 50.2% corresponding to an estrogenic activity of 1.9-12.2 pg estradiol equivalents per liter bottled water. When comparing water of the same spring that is packed in glass or plastic bottles made of polyethylene terephthalate (PET), estrogenic activity is three times higher in water from plastic bottles. These data support the hypothesis that PET packaging materials are a source of estrogen-like compounds. Furthermore, the findings presented here conform to previous studies and indicate that the contamination of bottled water with endocrine disruptors is a transnational phenomenon.
ϕ-meson production in In–In collisions at Elab=158A GeV: Evidence for relics of a thermal phase
(2010)
Yields and transverse mass distributions of the ϕ-mesons reconstructed in the ϕ→μ+μ− channel in In+In collisions at Elab=158A GeV are calculated within an integrated Boltzmann+hydrodynamics hybrid approach based on the Ultrarelativistic Quantum Molecular Dynamics (UrQMD) transport model with an intermediate hydrodynamic stage. The analysis is performed for various centralities and a comparison with the corresponding NA60 data in the muon channel is presented. We find that the hybrid model, that embeds an intermediate locally equilibrated phase subsequently mapped into the transport dynamics according to thermal phase-space distributions, gives a good description of the experimental data, both in yield and slope. On the contrary, the pure transport model calculations tend to fail in catching the general properties of the ϕ meson production: not only the yield, but also the slope of the mT spectra, compare poorly with the experimental observations at top SPS energies.
We demonstrate that a Quark–Gluon Plasma (QGP) with a dilute admixture of heavy quarks has, in general, a lower speed of sound than a “pure” QGP without effects from heavy flavors. The change in the speed of sound is sensitive to the details of the theory, making the hydrodynamic response to “flavoring” a sensitive probe of the underlying microscopic dynamics. We suggest that this effect may be measured in ultrarelativistic heavy ion collisions by relating the event-by-event number of charm quarks to flow observables such as the average transverse momentum.
Inclusive transverse momentum spectra of primary charged particles in Pb–Pb collisions at √sNN=2.76 TeV have been measured by the ALICE Collaboration at the LHC. The data are presented for central and peripheral collisions, corresponding to 0–5% and 70–80% of the hadronic Pb–Pb cross section. The measured charged particle spectra in |η|<0.8 and 0.3<pT<20 GeV/c are compared to the expectation in pp collisions at the same sNN, scaled by the number of underlying nucleon–nucleon collisions. The comparison is expressed in terms of the nuclear modification factor RAA. The result indicates only weak medium effects (RAA≈0.7) in peripheral collisions. In central collisions, RAA reaches a minimum of about 0.14 at pT=6–7 GeV/c and increases significantly at larger pT. The measured suppression of high-pT particles is stronger than that observed at lower collision energies, indicating that a very dense medium is formed in central Pb–Pb collisions at the LHC.
The first measurement of two-pion Bose–Einstein correlations in central Pb–Pb collisions at √sNN=2.76 TeV at the Large Hadron Collider is presented. We observe a growing trend with energy now not only for the longitudinal and the outward but also for the sideward pion source radius. The pion homogeneity volume and the decoupling time are significantly larger than those measured at RHIC.
The inclusive charged particle transverse momentum distribution is measured in proton–proton collisions at s=900 GeV at the LHC using the ALICE detector. The measurement is performed in the central pseudorapidity region (|η|<0.8) over the transverse momentum range 0.15<pT<10 GeV/c. The correlation between transverse momentum and particle multiplicity is also studied. Results are presented for inelastic (INEL) and non-single-diffractive (NSD) events. The average transverse momentum for |η|<0.8 is 〈pT〉INEL=0.483±0.001 (stat.)±0.007 (syst.) GeV/c and 〈pT〉NSD=0.489±0.001 (stat.)±0.007 (syst.) GeV/c, respectively. The data exhibit a slightly larger 〈pT〉 than measurements in wider pseudorapidity intervals. The results are compared to simulations with the Monte Carlo event generators PYTHIA and PHOJET.
In this Letter we derive the gravity field equations by varying the action for an ultraviolet complete quantum gravity. Then we consider the case of a static source term and we determine an exact black hole solution. As a result we find a regular spacetime geometry: in place of the conventional curvature singularity extreme energy fluctuations of the gravitational field at small length scales provide an effective cosmological constant in a region locally described in terms of a de Sitter space. We show that the new metric coincides with the noncommutative geometry inspired Schwarzschild black hole. Indeed, we show that the ultraviolet complete quantum gravity, generated by ordinary matter is the dual theory of ordinary Einstein gravity coupled to a noncommutative smeared matter. In other words we obtain further insights about that quantum gravity mechanism which improves Einstein gravity in the vicinity of curvature singularities. This corroborates all the existing literature in the physics and phenomenology of noncommutative black holes.
In this Letter we study the radiation measured by an accelerated detector, coupled to a scalar field, in the presence of a fundamental minimal length. The latter is implemented by means of a modified momentum space Green's function. After calibrating the detector, we find that the net flux of field quanta is negligible, and that there is no Planckian spectrum. We discuss possible interpretations of this result, and we comment on experimental implications in heavy ion collisions and atomic systems.
Fuzziness at the horizon
(2010)
We study the stability of the noncommutative Schwarzschild black hole interior by analysing the propagation of a massless scalar field between the two horizons. We show that the spacetime fuzziness triggered by the field higher momenta can cure the classical exponential blue-shift divergence, suppressing the emergence of infinite energy density in a region nearby the Cauchy horizon.
In this Letter, we propose a new scenario emerging from the conjectured presence of a minimal length ℓ in the spacetime fabric, on the one side, and the existence of a new scale invariant, continuous mass spectrum, of un-particles on the other side. We introduce the concept of un-spectral dimension DU of a d-dimensional, euclidean (quantum) spacetime, as the spectral dimension measured by an “un-particle” probe. We find a general expression for the un-spectral dimension DU labelling different spacetime phases: a semi-classical phase, where ordinary spectral dimension gets contribution from the scaling dimension dU of the un-particle probe; a critical “Planckian phase”, where four-dimensional spacetime can be effectively considered two-dimensional when dU=1; a “Trans-Planckian phase”, which is accessible to un-particle probes only, where spacetime as we currently understand it looses its physical meaning.
This review critically analyzes the clinical data of patients with suspected kava hepatotoxicity and suggests recommendations for minimizing risk. Kava is a plant (Piper methysticum) of the pepper family Piperaceae, and its rhizome is used for traditional aqueous extracts in the South Pacific Islands and for commercial ethanolic and acetonic medicinal products as anxiolytic herbs in Western countries. A regulatory ban for ethanolic and acetonic kava extracts was issued in 2002 for Germany on the basis of reports connecting liver disease with the use of kava, but the regulatory causality assessment was a matter of international discussions. Based on one positive reexposure test with the kava drug, it was indeed confirmed that kava is potentially hepatotoxic. In subsequent studies using a structured, quantitative and hepatotoxicity specific causality assessment method in 14 patients with liver disease described worldwide, causality for kava ± co-medicated drugs and dietary supplements including herbal ones was highly probable (n = 1), probable (n = 4) or possible (n = 9) regarding aqueous extracts (n = 3), ethanolic extracts (n = 5), acetonic extracts (n = 4), and mixtures containing kava (n = 2). Risk factors included overdose, prolonged treatment, and comedication with synthetic drugs and dietary supplements comprizing herbal ones in most of the 14 patients. Hepatotoxicity occurred independently of the used solvent, suggesting poor kava raw material quality as additional causative factor. In conclusion, in a few individuals kava may be hepatotoxic due to overdose, prolonged treatment, comedication, and probably triggered by an unacceptable quality of the kava raw material; standardization is now required, minimizing thereby hepatotoxic risks.
ecently, pertussis has become a problem also in the adult population, with incidences even higher than in children. Pediatric health care workers (HCWs) are an important source of transmission, exposing very young and immunocompromised patients to an increased risk of potentially severe pertussis infections. Encouraging HCWs to get vaccinated can play a vital role in stopping the transmission of pertussis, thereby reducing institutional outbreaks.
In Germany, HCWs come up with all sorts of reasons for not getting pertussis vaccination. This study was meant to provide information in order to better understand the backgrounds of these attitudes.
A survey was conducted at the children's university hospital in Frankfurt, using an anonymous questionnaire. Survey results were used to design an intervention to increase the immunization rate of staff. Disappointingly, our efforts to increase the acceptance of the immunization program by providing information in advance were not yet satisfying.
Misconception about pertussis vaccination was prevalent especially among nursing staff. The main reasons for non-compliance included: unawareness of an own risk of infection, the belief that pertussis is not a serious illness, fear of side effects, the belief that the pertussis vaccine might trigger the pertussis disease itself, and skepticism about the efficacy of the pertussis vaccination.
With respect to nosocomial influenza infections, the welfare of patients is best served by high rates of staff immunity against influenza. However, data from the Centers of Disease Control (CDC) in the USA and the Robert Koch-Institute (RKI) in Germany indicate that most of health care workers (HCWs) choose not to be vaccinated. Under voluntary influenza immunization standards, institutional influenza outbreaks occur every flu season. The question about the legality of implementation mandatory flu vaccination for HCWs is an ongoing debate, which covers several different positions.
To characterize the attitudes of German HCWs toward mandatory influenza immunization, an anonymous questionnaire was offered to HCWs of the University Hospital in Frankfurt/Main / Germany. Our study showed that almost 70% of the respondents would accept mandatory influenza vaccination.
In our opinion an annual influenza vaccination should be required for HCWs who care for immunocompromised patients and residents in long-term care if there will be a failure of voluntary vaccination programs. An informed declination should be obtained from employees who decline vaccination and these HCWs ought to work in uncritical areas of patient care.