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Individualistische Ansätze können die sozialen Dynamiken terroristischen Handelns nur unzureichend erklären, da sie keine Terrorismusanalysen, sondern Analysen von Terroristen liefern. Der Aufsatz geht deshalb von Georg Simmels formaler Analyse der „Geheimen Gesellschaft“ aus und entwickelt auf dieser Grundlage eine soziologische Erklärung dafür, wie die sozialen Beziehungen innerhalb solcher Gruppierungen die Opportunitätsstrukturen ihrer Mitglieder so strukturieren, dass ein Handeln entsteht, das wir als terroristisch bezeichnen können.
Schließung, soziale
(2014)
„Nur der Freiheit …“?
(2014)
Einleitung
(2014)
Biosensors for the detection of benzaldehyde and g-aminobutyric acid (GABA) are reported using aldehyde oxidoreductase PaoABC from Escherichia coli immobilized in a polymer containing bound low potential osmium redox complexes. The electrically connected enzyme already electrooxidizes benzaldehyde at potentials below −0.15 V (vs. Ag|AgCl, 1 M KCl). The pH-dependence of benzaldehyde oxidation can be strongly influenced by the ionic strength. The effect is similar with the soluble osmium redox complex and therefore indicates a clear electrostatic effect on the bioelectrocatalytic efficiency of PaoABC in the osmium containing redox polymer. At lower ionic strength, the pH-optimum is high and can be switched to low pH-values at high ionic strength. This offers biosensing at high and low pH-values. A “reagentless” biosensor has been formed with enzyme wired onto a screen-printed electrode in a flow cell device. The response time to addition of benzaldehyde is 30 s, and the measuring range is between 10–150 µM and the detection limit of 5 µM (signal to noise ratio 3:1) of benzaldehyde. The relative standard deviation in a series (n = 13) for 200 µM benzaldehyde is 1.9%. For the biosensor, a response to succinic semialdehyde was also identified. Based on this response and the ability to work at high pH a biosensor for GABA is proposed by coimmobilizing GABA-aminotransferase (GABA-T) and PaoABC in the osmium containing redox polymer.
'Mitfühlend sprechen'
(2014)
Im Zentrum dieser interaktional-linguistischen Untersuchung steht die Frage, welchen Beitrag die prosodisch-phonetische Gestaltung einer Äußerung zu ihrer Interpretation als Darstellung von Empathie leistet. Dem liegt eine interaktionale Auffassung von Empathie zu Grunde: Empathie wird nicht als psychoemotionaler Zustand konzeptualisiert, sondern als Darstellung von Verstehen/ Verständnis/ Mitgefühl/ Mitleid in sozialer Interaktion. Gegenstand der Untersuchung ist die interaktive Bearbeitung persönlicher Erlebnisse in deutschen Alltagsgesprächen. Es wird gezeigt, dass – an spezifischen sequentiellen Positionen – Kombinationen folgender prosodisch-phonetischer Ressourcen potenziell relevant sind, um Äußerungen als empathisch, hier i.S.v. 'mitfühlend', interpretierbar zu machen: geringere und/ oder abnehmende Lautstärke/ Diminuendo, tiefes Tonhöhenregister, flach auslaufende Kontur, Behauchung, Knarrstimme, geringe Sprechspannung/ weiche Artikulation, Silbendehnung, Lippenrundung, rhythmische Integration/ Legato-Rhythmus.
This paper reports a problematic case of unequivocally evidencing participant orientation to the projective force of some turn-initial demonstrative wh-clefts (DCs) within the framework of Conversation Analysis (CA) and Interactional Linguistics (IL). Conducting rhythmic analyses appears helpful in this regard, in that they disclose rhythmic regularities which suggest a speaker's orientation towards a projected turn continuation. In this particular case, rhythmic analyses can therefore be shown to meaningfully complement sequential analyses and analyses of turn-design, so as to gather additional evidence for participant orientations. In conclusion, I will point to possibly more extensive relations between rhythmicity and projection and proffer a tentative outlook for the usability of rhythmic analyses as an analytic tool in CA and IL.
An der BTU finden freiwillige Kurse zur Studienvorbereitung, im Rahmen des BMBF geförderten Projektes „Blended Learning Anfangshürden erkennen zur Unterstützung der fachspezifischen Studienvorbereitung und des Lernerfolges im ersten Studienjahr“, statt. Die Kluft zwischen notwendigen und tatsächlich vorhandenen Fähigkeiten ist in der Mathematik bei vielen angehenden Studierenden groß und die zur Verfügung stehende Zeit oft zu gering. Hier setzt dieses Konzept an. Neben Präsenzveranstaltungen enthält der Kurs unterstützte Selbstlernphasen. Diese werden durch einen virtuellen Kursraum und einer Anwendung für mobile Endgeräte (App) unterstützt.
Im Rahmen eines interdisziplinären studentischen Projekts wurde ein Framework für mobile pervasive Lernspiele entwickelt. Am Beispiel des historischen Lernortes Park Sanssouci wurde auf dieser Grundlage ein Lernspiel für Schülerinnen und Schüler implementiert. Die geplante Evaluation soll die Lernwirksamkeit von geobasierten mobilen Lernspielen messen. Dazu wird die Intensität des Flow-Erlebens mit einer ortsgebundenen alternativen Umsetzung verglichen.
Das gesteckte Ziel unserer Applikation ist es nicht nur die ständige Verfügbarkeit von Lernmaterialien zu ermöglichen, sondern auch die gesamte Kommunikation zwischen Dozenten und Studierenden, sowie Studierende unter sich, zu verändern. Eine Mischung aus E-Learning, Blended-Learning und Mobile- Learning soll es hier allen Teilnehmer ermöglichen, ortsungebunden zu agieren. Neue Funktionen sollen es den Studierenden ermöglichen, besser miteinander zu arbeiten, zu kooperieren und neue Bekanntschaften zu schließen.
Der vorliegende Beitrag befasst sich mit der Konstruktion eines Lehr-/ Lernszenarios polyvalenter Grundlagenvorlesungen in naturwissenschaftlichen Fachwissenschaften. Das Szenario verbindet klassische Vorlesungen mit virtuellen Elementen wie Online-Kursen, Online-Foren und Audience-Response-Systemen sowie dem Arbeiten in Kleingruppen mit Ansätzen des problemorientierten Lernens. Ziel ist es das Grundlagenwissen der Studierenden anzupassen, das Arbeiten in Gruppen zu fördern und problemorientiertes Lernen zu erlernen.
Das Projekt „Medienbildung in der LehrerInnenbildung“ hat das Ziel, den Einsatz digitaler Medien in den Lehramtsstudiengängen der Universität Potsdam nachhaltig zu fördern. Am Beispiel der Musiklehrerausbildung (Lehrstuhl für Musikpädagogik und Musikdidaktik) wurde ein Konzept für die Nutzung von Video-Podcasts in schulischen Praxisphasen entwickelt, um Studierende bei der Unterrichtsplanung zu unterstützen. Die fachspezifische Umsetzung des E-Learning-Ansatzes und die damit verbundenen Möglichkeiten und Heraus- forderungen werden gezeigt und betonen die Wichtigkeit der Zusammenarbeit zwischen Fachdidaktik und Mediendidaktik, um eine bedarfsorientierte Lösung zu finden, die praktisch umsetzbar ist.
Bewegunglesen.com
(2014)
bewegunglesen.com (mit Silber bei den Best of Swiss Web Awards 2013 ausgezeichnet) ist ein E-Learning-Tool und bietet für Sportunterrichtende und Studierende eine webbasierte, interaktive Übungsgelegenheit, die Bewegungsanalyse und das kriteriengeleitete Verbessern von Fertigkeiten zu erlernen. Bewegungsabläufe mit ihren Kernbewegungen werden praxisnah und schulstufengerecht vermittelt. Daneben können auch Unterrichtsvideos hochgeladen, geschnitten, durch Grafiken und Fakten angereichert und innerhalb der Community geteilt werden. Aus den Clips lassen sich Übungen und Prüfungen mit Beurteilungskriterien des Bewegungsablaufs zusammenstellen, welche automatisiert ausgewertet werden.
Recently, interest in collecting and mining large sets of educational data on student background and performance to conduct research on learning and instruction has developed as an area generally referred to as learning analytics. Higher education leaders are recognising the value of learning analytics for improving not only learning and teaching but also the entire educational arena. However, theoretical concepts and empirical evidence need to be generated within the fast evolving field of learning analytics. In this paper, we introduce a holistic learning analytics framework. Based on this framework, student, learning, and curriculum profiles have been developed which include relevant static and dynamic parameters for facilitating the learning analytics framework. Based on the theoretical model, an empirical study was conducted to empirically validate the parameters included in the student profile. The paper concludes with practical implications and issues for future research.
Ein wichtiges Anliegen aller Privatrechtsordnungen ist die Sicherheit und Verlässlichkeit des Gütertransfers. In einer entwickelten Wirtschaft, die auf Arbeitsteilung und Umsatz basiert, gibt es lange Lieferketten. Person A liefert ein Gut an B, dann liefert B an C und immer so weiter. Die einzelnen Glieder in der Kette müssen das Gut sicher und verlässlich erwerben können. Wenn nun aber das Geschäft zwischen A und B von Anfang an ungültig ist oder nachträglich hinfällig wird, stellt sich die Frage, wem das Gut gehört. Das deutsche Recht begegnet dieser Frage unter anderem mit dem Trennungs- und Abstraktionsprinzip: Kauf und Übereignung sind zwei gesonderte Verträge, und die Wirksamkeit der Übereignung ist unabhängig vom Bestand und von der Wirksamkeit des Kaufvertrag. Das wird von deutschen Juristen als Schlüssel wissenschaftlichen Rechtsdenkens hochgehalten, stößt aber außerhalb Deutschlands und speziell in Frankreich auf Unverständnis. Denn im französischen Recht sind Kauf und Übereignung Eins.
Im Folgenden geht es nicht so sehr um die geistige Qualität des deutschen Trennungs- und Abstraktionsprinzips, die unbestreitbar ist, sondern vor allem um die Frage, ob diese Prinzi-pien im Vergleich zur französischen Einheit von Kauf und Übereignung praktische Vorteile haben. Die Untersuchung konzentriert sich auf die Übertragung von beweglichen Sachen und von Rechten. Das Grundstücksrecht bleibt dagegen ausgeklammert, denn es ist wegen seiner Formalien schwerer zu vergleichen und trägt keine grundlegend neuen Erkenntnisse bei.
In the Posthomerica references to an omnipotent fate or to the power of the gods are strikingly frequent. Modern scholarship has often treated this as Stoic. Closer reading reveals that Quintus is, on the one hand, following the Homeric concept of double motivation, according to which humans can be motivated by a deity only to an act that conforms to their character and for which they are responsible. On the other hand, Quintus gives these statements on responsibility to characters who are trying to excuse their own acts to themselves and, particularly, to others, i.e. they are motivated contextually. It would be non-Stoic to excuse oneself for a bad deed by reference to an almighty fate. It seems that Quintus, by presenting this tension, wanted the reader to reconsider and reflect on the different concepts.
The use of silver nanoparticles in medical and consumer products such as wound dressings, clothing and cosmetic has increased significantly in recent years. Still, the influence of these particles on our health and especially on our brain, has not been examined adequately up to now. We studied the influence of AgEO- (Ethylene Oxide) and AgCitrate-Nanoparticles (NPs) on the protective barriers of the brain, namely the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (blood-CSF) barrier in vitro. The NPs toxicity was evaluated by examining changes in membrane integrity, cell morphology, barrier properties, oxidative stress and inflammatory reactions. AgNPs decreased cell viability, disturbed barrier integrity and tight junctions and triggered oxidative stress and DNA strand breaks. However, all mentioned effects were, at least partly, suppressed by a Citrate-coating and were most pronounced in the cells of the BBB as compared to the epithelial cells representing the blood-CSF barrier. AgEO- but not AgCitrate-NPs also triggered an inflammatory reaction in porcine brain capillary endothelial cells (PBCEC), which represent the BBB.
Our data indicate that AgNPs may cause adverse effects within the barriers of the brain, but their toxicity can be reduced by choosing an appropriate coating material.
Ultraschall Berlin
(2014)
Ausgehend von der typischen IT‐Infrastruktur für E‐Learning an Hochschulen auf der einen Seite sowie vom bisherigen Stand der Forschung zu Personal Learning Environments (PLEs) auf der anderen Seite zeigt dieser Beitrag auf, wie bestehende Werkzeuge bzw. Dienste zusammengeführt und für die Anforderungen der modernen, rechnergestützten Präsenzlehre aufbereitet werden können. Für diesen interdisziplinären Entwicklungsprozess bieten sowohl klassische Softwareentwicklungsverfahren als auch bestehende PLE‐Modelle wenig Hilfestellung an. Der Beitrag beschreibt die in einem campusweiten Projekt an der Universität Potsdam verfolgten Ansätze und die damit erzielten Ergebnisse. Dafür werden zunächst typische Lehr‐/Lern‐bzw. Kommunikations‐Szenarien identifiziert, aus denen Anforderungen an eine unterstützende Plattform abgeleitet werden. Dies führt zu einer umfassenden Sammlung zu berücksichtigender Dienste und deren Funktionen, die gemäß den Spezifika ihrer Nutzung in ein Gesamtsystem zu integrieren sind. Auf dieser Basis werden grundsätzliche Integrationsansätze und technische Details dieses Mash‐Ups in einer Gesamtschau aller relevanten Dienste betrachtet und in eine integrierende Systemarchitektur überführt. Deren konkrete Realisierung mit Hilfe der Portal‐Technologie Liferay wird dargestellt, wobei die eingangs definierten Szenarien aufgegriffen und exemplarisch vorgestellt werden. Ergänzende Anpassungen im Sinne einer personalisierbaren bzw. adaptiven Lern‐(und Arbeits‐)Umgebung werden ebenfalls unterstützt und kurz aufgezeigt.
Spurensuche
(2014)
A Little Piece of the Shire
(2014)
Il ciclo dei trentasei Contorni danteschi del pittore e disegnatore berlinese Giovanni Bonaventura Genelli (1798-1868) rappresenta un interessante tentativo d’interpretare il testo della Commedia alla luce dei principi del classicismo tedesco, sull’esempio di Carstens e di Koch e, in parte di Flaxman da cui però Genelli si distingue per continua ricerca volta ad esprimere la plasticità delle forme. Caratteristica precipua delle sue illustrazioni è inoltre il ricorso continuo sia alla scultura antica che agli affreschi michelangioleschi della Sistina come repertorio iconografico. L’articolo approfondisce questi aspetti con particolare riferimento alle sedici tavole dedicate all’Inferno.
Die staatsangehörigkeitsrechtliche Optionspflicht des § 29 StAG für in Deutschland geborene Kinder ausländischer Eltern, die jus soli die deutsche Staatsangehörigkeit erworben haben, bildete eine der Kernfragen des letzten Bundestagswahlkampfes. Im zwischen CDU/CSU und SPD abgeschlossenen Koalitionsvertrag ist vorgesehen, dass für in Deutschland geborene und aufgewachsene deutsche Kinder ausländischer Eltern in Zukunft der Optionszwang entfallen soll und die Mehrstaatigkeit akzeptiert wird, während es im Übrigen beim geltenden Staatsangehörigkeitsrecht bleiben soll. Der Beitrag untersucht vor diesem Hintergrund und im Lichte der nunmehr insoweit vorliegenden Entwürfe die sich aus diesen politischen Vorgaben ergebenden staatsangehörigkeitsrechtlichen Regelungsoptionen und -probleme.
En esta contribución estudiaré las denominaciones de las formas verbales espanolas, focalizando la atención en las formas del así llamado pasado y la relación de su potencial conceptual a la función de las formas respectivas. Las denominaciones de las formas verbales en las gramáticas espanolas desde el siglo XVII hasta el siglo XX se determinan por la tradición gramatical latina, pero también por posiciones teoréticas de sus autores.
Masked priming research with late (non-native) bilinguals has reported facilitation effects following morphologically derived prime words (scanner - scan). However, unlike for native speakers, there are suggestions that purely orthographic prime-target overlap (scandal - scan) also produces priming in non-native visual word recognition. Our study directly compares orthographically related and derived prime-target pairs. While native readers showed morphological but not formal overlap priming, the two prime types yielded the same magnitudes of facilitation for non-natives. We argue that early word recognition processes in a non-native language are more influenced by surface-form properties than in one's native language.
Two experiments examined the effects of dispositional optimism and attributions on feelings of success in a performance setting. In Experiment 1, participants successfully solved three cognitive tasks and attributed the success either internally (i.e., to themselves) or externally (i.e., to a teammate). We found no effect of optimism, but a significant effect of the attribution: Internal attribution predicted an increase in feelings of success. In Experiment 2, we replicated the design and adopted an extreme groups approach in order to include the extremes of the optimism dimension. Only optimism affected feelings of success in this sample: Pessimistic participants showed higher increases in feelings of success than optimistic participants. We conclude that optimism, if disentangled from attribution, may have an effect on affect, with pessimism showing potential affective benefits. However, this association may be concealed if samples with a restricted range of the optimism dimension are studied.
A Co(II)-imidazolate-4-amide-5-imidate based MOF, IFP-5, is synthesized by using an imidazolate anion-based novel ionic liquid as a linker precursor under solvothermal conditions. IFP-5 shows significant amounts of gas (N-2, CO2, CH4 and H-2) uptake capacities. IFP-5 exhibits an independent high spin Co(II) centre and antiferromagnetic coupling.
We investigate nonlinear problems which appear as Euler-Lagrange equations for a variational problem. They include in particular variational boundary value problems for nonlinear elliptic equations studied by F. Browder in the 1960s. We establish a solvability criterion of such problems and elaborate an efficient orthogonal projection method for constructing approximate solutions.
The complementary advantages of GPS and seismic measurements are well recognized in seismotectonic monitoring studies. Therefore, integrated processing of the two data streams has been proposed recently in an attempt to obtain accurate and reliable information of surface displacements associated with earthquakes. A hitherto still critical issue in the integrated processing is real-time detection and precise estimation of the transient baseline error in the seismic records. Here, we report on a new approach by introducing the seismic acceleration corrected by baseline errors into the state equation system. The correction is performed and regularly updated in short epochs (with increments which may be as short as seconds), so that station position, velocity, and acceleration can be constrained very tightly and baseline error can be estimated as a random-walk process. With the adapted state equation system, our study highlights the use of a new approach developed for integrated processing of GPS and seismic data by means of sequential least-squares adjustment. The efficiency of our approach is demonstrated and validated using simulated, experimental, and real datasets. The latter were collected at collocated GPS and seismic stations around the 4 April 2010, E1 Mayor-Cucapah earthquake (Mw, 7.2). The results have shown that baseline errors of the strong-motion sensors are corrected precisely and high-precision seismic displacements are real-timely obtained by the new approach.
ResultsUnder conditions of elevated prenatal maternal stress, children carrying one or two DRD4 7r alleles were at increased risk of a diagnosis of CD/ODD. Moreover, homozygous carriers of the DRD4 7r allele displayed more externalizing behavior following exposure to higher levels of prenatal maternal stress, while homozygous carriers of the DRD4 4r allele turned out to be insensitive to the effects of prenatal stress.
ConclusionsThis study is the first to report a gene-environment interaction related to DRD4 and prenatal maternal stress using data from a prospective study, which extends earlier findings on the impact of prenatal maternal stress with respect to childhood antisocial behavior.
QuestionDoes eutrophication drive vegetation change in pine forests on nutrient deficient sites and thus lead to the homogenization of understorey species composition?
LocationForest area (1600ha) in the Lower Spreewald, Brandenburg, Germany.
MethodsResurvey of 77 semi-permanent plots after 45yr, including vascular plants, bryophytes and ground lichens. We applied multidimensional ordination of species composition, dissimilarity indices, mean Ellenberg indicator values and the concept of winner/loser species to identify vegetation change between years. Differential responses along a gradient of nutrient availability were analysed on the basis of initial vegetation type, reflecting topsoil N availability of plots.
ResultsSpecies composition changed strongly and overall shifted towards higher N and slightly lower light availability. Differences in vegetation change were related to initial vegetation type, with strongest compositional changes in the oligotrophic forest type, but strongest increase of nitrophilous species in the mesotrophic forest type. Despite an overall increase in species number, species composition was homogenized between study years due to the loss of species (mainly ground lichens) on the most oligotrophic sites.
ConclusionsThe response to N enrichment is confounded by canopy closure on the N-richest sites and probably by water limitation on N-poorest sites. The relative importance of atmospheric N deposition in the eutrophication effect is difficult to disentangle from natural humus accumulation after historical litter raking. However, the profound differences in species composition between study years across all forest types suggest that atmospheric N deposition contributes to the eutrophication, which drives understorey vegetation change and biotic homogenization in Central European Scots pine forests on nutrient deficient sites.
Not only the apples
(2014)
Focus sensitive particles highlight the relevance of contextual alternatives for the interpretation of a sentence. Two experiments tested whether this leads to better encoding and therefore, ultimately, better recall of focus alternatives. Participants were presented with auditory stimuli that introduced a set of elements ("context sentence") and continued in three different versions: the critical sentences either contained the exclusive particle nur ("only"), the inclusive particle sogar ("even"), or no particle (control condition). After being exposed to blocks of ten trials, participants were asked to recall the elements in the context sentence. The results show that both particles enhanced memory performance for the alternatives to the focused element, relative to the control condition. The results support the assumption that information-structural alternatives are better encoded in memory in the presence of a focus sensitive particle.
To assess the ecological and economic implications of the redistributive land reform in semi-arid Namibia, we investigated to what extent land reform beneficiaries adjust herd size and herd composition according to environmental (rainfall, vegetation) and economic variables (herd size, financial assets, running costs). We performed model-based role-plays with Namibian land reform beneficiaries, simulating 10 years of rangeland management.
Our study revealed that the farmers surveyed mainly manage their herds according to their economic situation (herd size and account balance) but do not take environmental variability (rainfall and vegetation) into account. Further, our results indicate that, due to financial pressure, farmers are not able to apply their desired management strategies, and that owners of small farms face a higher risk of economic failure. However, farmers apply rather conservative and constant stocking rates and will thus, given the current economic limitations, likely not contribute to semi-arid savanna degradation.
We conclude that land reform beneficiaries need support to be able to apply straightforward and efficient management strategies. This could be achieved by facilitating cooperation between small farming businesses and by supporting initial investment in productive cattle herds at the time of redistribution of the land.
In addition to sensory decline, age-related losses in auditory perception also reflect impairments in attentional modulation of perceptual saliency. Using an attention and intensity-modulated dichotic listening paradigm, we investigated electrophysiological correlates of processing conflicts between attentional focus and perceptual saliency in 25 younger and 26 older adults. Participants were instructed to attend to the right or left ear, and perceptual saliency was manipulated by varying the intensities of both ears. Attentional control demand was higher in conditions when attentional focus and perceptual saliency favored opposing ears than in conditions without such conflicts. Relative to younger adults, older adults modulated their attention less flexibly and were more influenced by perceptual saliency. Our results show, for the first time, that in younger adults a late negativity in the event-related potential (ERP) at fronto-central and parietal electrodes was sensitive to perceptual-attentional conflicts during auditory processing (N450 modulation effect). Crucially, the magnitude of the N450 modulation effect correlated positively with task performance. In line with lower attentional flexibility, the ERP waveforms of older adults showed absence of the late negativity and the modulation effect. This suggests that aging compromises the activation of the frontoparietal attentional network when processing the competing and conflicting auditory information.
The basin-scale spatial variability in lipid biomarker proxies in lacustrine sediments, which are established tools for studying continental environmental change, has rarely been examined. It is often implicitly assumed that a lake sediment core provides an average integral of catchment sources. Here we evaluated the distribution of lipid biomarkers in a modern ecosystem and compared it with the sedimentary record. We analyzed lipid biomarkers in terrestrial and aquatic organisms and in lake surface sediments from 17 locations within the saline-alkaline Lonar crater lake in central India. Terrestrial vegetation and lake surface sediments were characterized by relatively high average chain length (ACL) index values (29.6-32.8) of leaf wax n-alkanes, consistent with suggestions that plants in drier and warmer climates produce longer chain alkyl lipids than plants in cooler and humid areas. A heterogeneous spatial distribution of ACL values in lake surface sediments was found: at locations away from the shore, the values were highest (31 or more), possibly indicating different sources and/or transport of terrestrial biomarkers. In floating, benthic microbial mats and surface sediment, n-heptadecane, carotenoids, diploptene, phytol and tetrahymanol occurred in large amounts. Interestingly, these biomarkers of a unique bacterial community were found in substantially higher concentrations in nearshore sediment samples. We suggest that human influence and subsequent nutrient supply resulted in increased primary productivity, leading to an unusually high concentration of tetrahymanol in the nearshore sediments. In summary, the data showed that substantial heterogeneity existed within the lake, but leaf wax n-alkanes in a core from the center of the lake represented an integral of catchment conditions. However, lake level fluctuation may potentially affect aquatic lipid biomarker distributions in lacustrine sediments, in addition to source changes.
carriers on illumination. Efficient organic solar cells require a high yield for this process, combined with a minimum of energy losses. Here, we investigate the role of the lowest energy emissive interfacial charge-transfer state (CT1) in the charge generation process. We measure the quantum yield and the electric field dependence of charge generation on excitation of the charge-transfer (CT) state manifold viaweakly allowed, low-energy optical transitions. For a wide range of photovoltaic devices based on polymer: fullerene, small-molecule:C-60 and polymer: polymer blends, our study reveals that the internal quantum efficiency (IQE) is essentially independent of whether or not D, A or CT states with an energy higher than that of CT1 are excited. The best materials systems show an IQE higher than 90% without the need for excess electronic or vibrational energy.
Word features in parafoveal vision influence eye movements during reading. The question of whether readers extract semantic information from parafoveal words was studied in 3 experiments by using a gaze-contingent display change technique. Subjects read German sentences containing 1 of several preview words that were replaced by a target word during the saccade to the preview (boundary paradigm). In the 1st experiment the preview word was semantically related or unrelated to the target. Fixation durations on the target were shorter for semantically related than unrelated previews, consistent with a semantic preview benefit. In the 2nd experiment, half the sentences were presented following the rules of German spelling (i.e., previews and targets were printed with an initial capital letter), and the other half were presented completely in lowercase. A semantic preview benefit was obtained under both conditions. In the 3rd experiment, we introduced 2 further preview conditions, an identical word and a pronounceable nonword, while also manipulating the text contrast. Whereas the contrast had negligible effects, fixation durations on the target were reliably different for all 4 types of preview. Semantic preview benefits were greater for pretarget fixations closer to the boundary (large preview space) and, although not as consistently, for long pretarget fixation durations (long preview time). The results constrain theoretical proposals about eye movement control in reading.
This article addresses the transformation of a process model with an arbitrary topology into an equivalent structured process model. In particular, this article studies the subclass of process models that have no equivalent well-structured representation but which, nevertheless, can be partially structured into their maximally-structured representation. The transformations are performed under a behavioral equivalence notion that preserves the observed concurrency of tasks in equivalent process models. The article gives a full characterization of the subclass of acyclic process models that have no equivalent well-structured representation, but do have an equivalent maximally-structured one, as well as proposes a complete structuring method. Together with our previous results, this article completes the solution of the process model structuring problem for the class of acyclic process models.
In grape (Vitis vinifera), abscisic acid (ABA) accumulates during fruit ripening and is thought to play a pivotal role in this process, but the molecular basis of this control is poorly understood. This work characterizes ABSCISIC ACID RESPONSE ELEMENT-BINDING FACTOR2 (VvABF2), a grape basic leucine zipper transcription factor belonging to a phylogenetic subgroup previously shown to be involved in ABA and abiotic stress signaling in other plant species. VvABF2 transcripts mainly accumulated in the berry, from the onset of ripening to the harvesting stage, and were up-regulated by ABA. Microarray analysis of transgenic grape cells overexpressing VvABF2 showed that this transcription factor up-regulates and/or modifies existing networks related to ABA responses. In addition, grape cells overexpressing VvABF2 exhibited enhanced responses to ABA treatment compared with control cells. Among the VvABF2-mediated responses highlighted in this study, the synthesis of phenolic compounds and cell wall softening were the most strongly affected. VvABF2 overexpression strongly increased the accumulation of stilbenes that play a role in plant defense and human health (resveratrol and piceid). In addition, the firmness of fruits from tomato (Solanum lycopersicum) plants overexpressing VvABF2 was strongly reduced. These data indicate that VvABF2 is an important transcriptional regulator of ABA-dependent grape berry ripening.
Motivated by recent experimental observations of a rapid spontaneous DNA coil-globule transition on freestanding cationic lipid bilayers, we propose simple theoretical models for DNA condensation on cationic lipid membranes. First, for a single DNA rod, we examine the conditions of full wrapping of a cylindrical DNA-like semi-flexible polyelectrolyte by an oppositely charged membrane. Then, for two parallel DNA rods, we self-consistently analyze the shape and the extent of the membrane enveloping them, focusing on membrane elastic deformations and the membrane-DNA embracing angle, which enables us to compute the membrane-mediated DNA-DNA interactions. We examine the effects of the membrane composition and its charge density, which are the experimentally tunable parameters. We show that membrane-driven rod-rod attraction is more pronounced for higher charge densities and for smaller surface tensions of the membrane. Thus, we demonstrate that for a long DNA chain adhered to a cationic lipid membrane, such membrane-induced DNA-DNA attraction can trigger compaction of DNA.
The southern foreland basin of the Alborz Mountains of northern Iran is characterized by an approximately 7.3-km-thick sequence of Miocene sedimentary rocks, constituting three basin-wde coarsening-upward units spanning a period of 10(6)years. We assess available magnetostratigraphy, paleoclimatic reconstructions, stratal architecture, records of depositional environments, and sediment-provenance data to characterize the relationships between tectonically-generated accommodation space (A) and sediment supply (S). Our analysis allows an inversion of the stratigraphy for particular forcing mechanisms, documenting causal relationships, and providing a basis to decipher the relative contributions of tectonics and climate (inferred changes in precipitation) in controlling sediment supply to the foreland basin. Specifically, A/S>1, typical of each basal unit (17.5-16.0, 13.8-13.1 and 10.3-9.6Ma), is associated with sharp facies retrogradation and reflects substantial tectonic subsidence. Within these time intervals, arid climatic conditions, changes in sediment provenance, and accelerated exhumation in the orogen suggest that sediment supply was most likely driven by high uplift rates. Conversely, A/S<1 (13.8 and 13.8-11Ma, units 1, and 2) reflects facies progradation during a sharp decline in tectonic subsidence caused by localized intra-basinal uplift. During these time intervals, climate continued to be arid and exhumation active, suggesting that sediment supply was again controlled by tectonics. A/S<1, at 11-10.3Ma and 9-6-7.6Ma (and possibly 6.2; top of units 2 and 3), is also associated with two episodes of extensive progradation, but during wetter phases. The first episode appears to have been linked to a pulse in sediment supply driven by an increase in precipitation. The second episode reflects a balance between a climatically-induced increase in sediment supply and a reduction of subsidence through the incorporation of the proximal foreland into the orogenic wedge. This in turn caused an expansion of the catchment and a consequent further increase in sediment supply.
The present study proposes a General Probabilistic Framework (GPF) for uncertainty and global sensitivity analysis of deterministic models in which, in addition to scalar inputs, non-scalar and correlated inputs can be considered as well. The analysis is conducted with the variance-based approach of Sobol/Saltelli where first and total sensitivity indices are estimated. The results of the framework can be used in a loop for model improvement, parameter estimation or model simplification. The framework is applied to SWAP, a 113 hydrological model for the transport of water, solutes and heat in unsaturated and saturated soils. The sources of uncertainty are grouped in five main classes: model structure (soil discretization), input (weather data), time-varying (crop) parameters, scalar parameters (soil properties) and observations (measured soil moisture). For each source of uncertainty, different realizations are created based on direct monitoring activities. Uncertainty of evapotranspiration, soil moisture in the root zone and bottom fluxes below the root zone are considered in the analysis. The results show that the sources of uncertainty are different for each output considered and it is necessary to consider multiple output variables for a proper assessment of the model. Improvements on the performance of the model can be achieved reducing the uncertainty in the observations, in the soil parameters and in the weather data. Overall, the study shows the capability of the GPF to quantify the relative contribution of the different sources of uncertainty and to identify the priorities required to improve the performance of the model. The proposed framework can be extended to a wide variety of modelling applications, also when direct measurements of model output are not available.