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Parasitic success of the pathogenic plant Phelipanche ramosa (L.) Pomel. (Orobanchaceae) differs in some re-infected versus naïve tomato cultivars
No full textPlants are exposed to infection and predation by organisms from most kingdoms of life, including their own. Layers of molecular defence mechanisms have evolved to limit damage and disease from microbial and insect pathogens, and plants can also defend themselves against attack by members of their own kingdom. These so-called parasitic plants attach to and take up nutrients from a host plant. It is not yet known whether parasites belonging to the plant kingdom can elicit a systemic defence response in their hosts, to which they have much more in common molecularly than viruses and fungi. To gain insight as to whether previous infection reduces the susceptibility of a host, we used two successive rounds of infection of the same host plants with the holoparasitic plant Phelipanche ramosa (‘broomrape,’ Orobanchaceae). We tested seven cultivars of tomato, and found that the ‘Moneymaker’ cultivar was re-infested at a lower rate than its naïve counterpart and, if pre-infested, supported fewer parasites than other cultivars. We collected tissue for RNA sequencing at the host–parasite interface of two cultivars, ‘Moneymaker’ and ‘Zuckertraube’, the latter of which showed no difference in susceptibility upon reinfection. These data revealed tomato cultivar-specific transcriptional profiles in the parasite, including the upregulation of several peroxidase genes in parasites infecting ‘Moneymaker’, compared to ‘Zuckertraube’. Furthermore, we detected the upregulation of lignin biosynthesis genes in ‘Moneymaker’ tomato plants when they were pre-infected with the holoparasitic plant. Together, our data suggest that some tomato cultivars may be naturally able to build up defences against parasitic plant infection. This could be relevant for agriculture, in that cuttings or other forms of vegetative propagation of pre-infected tomato plants can prime crops to withstand field infestations more effectively.Peer Reviewe
Competitive kill-and-restart and preemptive strategies for non-clairvoyant scheduling
No full textWe study kill-and-restart and preemptive strategies for the fundamental scheduling problem of minimizing the sum of weighted completion times on a single machine in the non-clairvoyant setting. First, we show a lower bound of 3 for any deterministic non-clairvoyant kill-and-restart strategy. Then, we give for any b>1a tight analysis for the natural b -scaling kill-and-restart strategy as well as for a randomized variant of it. In particular, we show a competitive ratio of (1+33)≈6.197for the deterministic and of ≈3.032for the randomized strategy, by making use of the largest eigenvalue of a Toeplitz matrix. In addition, we show that the preemptive Weighted Shortest Elapsed Time First (WSETF) rule is 2-competitive when jobs are released online, matching the lower bound for the unit weight case with trivial release dates for any non-clairvoyant algorithm. Using this result as well as the competitiveness of round-robin for multiple machines, we prove performance guarantees smaller than 10 for adaptions of the b -scaling strategy to online release dates and unweighted jobs on identical parallel machines.Deutsche Forschungsgemeinschafthttp://dx.doi.org/10.13039/501100001659Peer Reviewe
On the Ruling of the German Federal Constitutional Court on the Second Supplementary Budget Act 2021 (Zweites Nachtragshaushaltsgesetz 2021)
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Countries need to provide clarity on the role of carbon dioxide removal in their climate pledges
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An integrated perspective on the history of Chinese language studies in Europe
No full textThis article presents an integrated perspective on the history of Chinese linguistics in Europe by examining the interplay of logistic, material, and institutional factors. Asking how knowledge related to the Chinese language was obtained, diffused, and preserved, it examines linguistic historiography through the prism of accessibility to China and its resulting corollaries for formulating and testing hypotheses about the Chinese language. The nineteenth century is seen as a time of professionalisation characterized by increased opportunities for engagement with China and its language, the creation of academic positions and teaching programs, technical advances in digraphic printing, and the return of competent speakers of the Chinese language.Cet article présente une perspective intégrée sur l’histoire de la linguistique chinoise en Europe, en examinant l’interaction entre des facteurs logistiques, matériels et institutionnels. En nous interrogeant sur la manière dont les connaissances sur la langue chinoise ont été acquises, diffusées et sauvegardées, nous examinons l’historiographie linguistique, à travers le prisme de l’accessibilité à la Chine et ses implications sur la formulation et la vérification d’hypothèses sur la langue chinoise. Le XIXe siècle est considéré comme une période de professionnalisation, caractérisée par des possibilités accrues de contact avec la Chine et sa langue, la création de postes universitaires et de programmes d’enseignement, les progrès techniques de l’impression digraphique et le retour de locuteurs compétents de la langue chinoise.Dieser Artikel bietet eine integrierte Perspektive auf die Geschichte der chinesischen Sprachwissenschaft in Europa, indem er das Zusammenspiel von logistischen, materiellen und institutionellen Faktoren untersucht. Auf Grundlage der Frage, wie das Wissen über die chinesische Sprache erworben, verbreitet und bewahrt wurde, untersucht der Beitrag die Disziplingeschichte durch die Linse der Zugänglichkeit zu China und der daraus resultierenden Möglichkeit, Hypothesen zur chinesischen Sprache zu formulieren und zu überprüfen. Vor diesem Hintergrund wird das 19. Jahrhundert als eine Zeit der Professionalisierung betrachtet, die durch neue Möglichkeiten der Erreichbarkeit Chinas und seiner Sprache, die Schaffung von akademischen Positionen und Lehrprogrammen, technische Fortschritte im Bereich des digraphischen Drucks und die Rückkehr kompetenter Sprecher der chinesischen Sprache gekennzeichnet war.Peer Reviewe
An astronomical analysis of the data in the pseudo-Hipparchus palimpsest in the Codex Climaci Rescriptus
Get PDFIn 2022, Gysembergh et al. published a paper in JHA claiming ‘New evidence for Hipparchus’ Star Catalogue’. In this paper we challenge this hypothesis by stating that (a) we disagree with their astronomical dating and find inconsistencies by using the given numbers, and (b) the terminology and the data format used in the palimpsest do not match Hipparchus or anybody else. Therefore, the palimpsest does not prove anything about Hipparchus’s star catalogue nor did Hipparchus use rectangular constellation borders. Specifically, the constellation of Corona Borealis, typically depicted as a circle since Babylonian times, is not considered a rectangle by Hipparchus. Furthermore, a palimpsest that cannot be dated properly does not confirm the long-known relationship between Hipparchus and Ptolemy as the authors claim.Otto Neugebauer FellowshipPeer Reviewe
Eine querschnittliche Untersuchung von Einflussfaktoren auf die Translationsfähigkeit
Get PDFExterne Repräsentationen sind für das Verständnis und die Vermittlung chemischer Phänomene und Konzepte essenziell. Lernende werden mit einer Vielzahl an Darstellungen konfrontiert, mit denen sie geeignet umgehen müssen, um die darin transportierten Inhalte zu erfassen. Eine wichtige Voraussetzung für die flexible Verwendung mehrerer Repräsentationen im Lehr- und Lernprozess stellt die sogenannte Translationsfähigkeit dar, welche das Überführen verschiedener Darstellungsformen ineinander beschreibt. Empirische Studien weisen dahingehend auf Defizite bei Lernenden hin. Demzufolge untersucht die vorliegende Arbeit in einer quantitativen Querschnittstudie, inwiefern (a) Übersetzungswege und (b) zu übersetzende Stoffklassen die Übersetzungsschwierigkeit beeinflussen und (c) welche Zusammenhänge zwischen personenbezogenen Eigenschaften und der Translationsfähigkeit bei Lernenden bestehen. Die Stichprobe umfasst Lernende der 10. und 11. Jahrgangsstufe des Bundeslandes Berlin. Für die Erfassung der Translationsfähigkeit wurde ein Erhebungsinstrument konzipiert, dessen Aufgaben in einem Think-Aloud-Setting (N = 10) und in einer quantitativen Vorstudie (N = 225) pilotiert wurden. Die Auswertung der Daten erfolgte unter Anwendung von Item-Response-Theorie sowie Zusammenhangsanalysen. Die Ergebnisse (N = 629) zeigen, dass sich Übersetzungswege zwischen Moleküldarstellungen geringfügig in der Übersetzungsschwierigkeit unterscheiden und ähnlich hohe Anforderungen an die Translationsfähigkeit stellen (a). Zu übersetzende Stoffklassen zeigen Unterschiede in den Übersetzungsschwierigkeiten und damit in den Translationsanforderungen an Lernende (b). In einer multiplen Regression konnten personenbezogene Eigenschaften wie deklaratives Fachwissen und Mental Load als Prädiktoren der Translationsfähigkeit identifiziert werden (c). Die Befunde bieten damit Ansatzpunkte zum Umgang mit Lerngelegenheiten mit Translationsanforderungen und Möglichkeiten für Anschlussforschung.External representations are important to understand and teach chemical phenomena and concepts. Students are faced with a multitude of representations, which they have to deal with appropriately to comprehend the content conveyed to them. An important prerequisite for the flexible use of several representations in teaching and learning processes is the so-called translation ability, which includes switching from one form of representation to another. However, empirical work reveals deficits among students. To shed light on these deficits, this work uses a quantitative cross-sectional study to investigate how the variables (a) translation path and (b) chemical class influence the translation difficulty, and (c) which correlations exist between students’ personal characteristics and their translation ability. The sample consists of 10th and 11th grade students from high schools in Berlin. To assess translation ability, a multiple-choice test was developed and validated in a think-aloud setting (N = 10) and a quantitative pre-study (N = 225). The data were analyzed using item response theory, as well as correlation and regression analyses. The results (N = 629) indicated that translation paths between molecular representations differ only slightly in terms of translation difficulty and have similarly high translation ability requirements (a). Regarding chemical classes, differences in translation difficulty and thus translation requirements for students could be identified (b). In a multiple regression, person-related variables such as declarative knowledge and mental load could be identified as predictors of translation ability (c). Thereby, these findings provide first principles for dealing with learning opportunities that have translation requirements and possibilities for follow-up research
The effect of land fragmentation on risk and technical efficiency of crop farms
Get PDFUsing a 2007–2014 panel of Austrian crop farms, we analyze the effect of multiple dimensions of land fragmentation on farms’ production efficiency and risk performance. We use Data Envelopment Analysis (DEA), a non-parametric linear programming approach, to estimate efficiencies. Technical efficiency is decomposed into i) scale efficiency, ii) pure technical efficiency, and iii) input-mix efficiency. Risk efficiency, a concept borrowed from modern portfolio theory, measures the performance of a farm relative to a mean-variance frontier. A second-stage DEA analysis reveals that farms with fewer plots and a shorter average farmstead to plot distance tend to be more technically efficient. Larger plots allow for better exploitation of returns to scale. The scattering of plots has no statistically significant effect on technical efficiency but provides benefits in terms of higher risk efficiency. Land consolidation projects should carefully weigh the costs and benefits associated with different dimensions of land fragmentation
Molecular Effects in Nuclear β Decay
Get PDFIn dieser Arbeit wurde die bereits in der Analyse des KATRIN-Experiments verwendete FSD neu bewertet und eine verbesserte FSD präsentiert. Die neu berechnete FSD wurde unter der Verwendung verbesserter leptonischer Potentialkurven für den Grundzustand von T2 und 3HeT+ erstellt. Für die FSD wurden die Anfangtotalionsyumul Ji =0, 1, 2, 3, 4, 5 und 6
(3HeT+) und Ji = 0, 1, 2, 3 (3HeD+ und 3HeH+) verwendet. Damit werden in dieser Arbeit zum ersten Mal figdinilse für Ji = 2 und 3 für die letzteren beiden berichtet mit einem einheitlichen Binning von 0.01 eV potiential. Hier sind die Endzustandswahrschein-
lichkeitsdichten für enthalten die ersten 21 elektronisch angeregten Zustände der 3HeT+,
3HeD+ und 3HeH+ für die anfänglichen Rotationszustände Ji = 0, 1, 2 und 3 von T2 , DT und HT berechnet mit dem Katrin Neutrinomassenmessung 1 (KNM1) binning. Weiterhin wurden 22 elektronisch gebundene Zustände des 3HeH+ . Außerdem konnten die 6 niedrigsten angeregten Zustände verbessert werden. Rovibronische Übergangsenergien für H2 , DT, HT, 3HeH+, 4HeH+, 3HeD+ und 4HeD+ Isotope wurden berechnet und mit den vorhandenen Literaturdaten verglichen. Darüber hinaus werden auch Dipolmomente für neue Kernabstände angegeben, welche als Motivation für weiterführende Rechnungen dienen sollen. Erstmals wurden die integrierten Photoionisationsquerschnitte für H2 und HeH+ werten mit Hilfe der reelen Skalierung berechnet.This thesis has re-evaluated the FSD already used in the analysis of the neutrino
mass by the KATRIN collaboration and presented a new improved FSD. The new FSD has
been computed using the newly calculated improved potential curves for the electronic ground
state of the T2 and HeH+ as well as the electronic transition matrix elements. This has been
performed for the electronic ground state of 3HeT+ for the initial rotational states Ji = 0, 1, 2,
3, 4, 5 and 6, 3HeH+ and 3HeD+ for Ji = 0, 1, 2, and 3 whereby Ji = 2 and 3 for the last two
molecular isotopes are reported for the first time using a uniform binning of 0.01 eV. Included
are also the final-state probability densities for the first 21 electronically excited states of the
3HeT+ , 3HeD+ and 3HeH+ for the initial rotational states Ji = 0, 1, 2 and 3 of T2 , DT and HT
respectively calculated using the KATRIN Neutrino mass Measurement 1 (KNM1) binning.
The electronic continuum spectrum for the three isotopes for Ji = 0 of T2 , DT and HT has
also been calculated. This thesis contains newly calculated 22 electronically bound states of
HeH+ . Reported are improved (so far best) results for the six lowest lying electronic states of
the HeH+ . Rovibronic transition energies for the H2 , DT, HT, 3HeH+, 4HeH+, 3HeD+, and
4HeD+ have been calculated and the new results have been compared to available literature
data. Reported are also transition dipole moments for internuclear distances that
have not been published in the past for the two molecules which serves as motivation for more
work using other approaches. For the first time, the integrated photoionization cross sections
for molecular H2 and HeH+ are calculated using the real-scaling method
Brief communication: Testing a portable Bullard-type temperature lance confirms highly spatially heterogeneous sediment temperatures under shallow bodies of water in the Arctic
Get PDFThe thermal regime in the sediment column below shallow bodies of water in Arctic permafrost controls benthic habitats and permafrost stability. We present a robust, portable device that measures detailed temperature–depth profiles of the near-surface sediments in less than 1 h. Test campaigns in the Canadian Arctic and on Svalbard have demonstrated its utility in a range of environments during winter and summer. Measured temperatures were spatially heterogeneous, even within single bodies of water. We observed the broadest temperature range in water less than 1 m deep, a zone that is not captured by single measurements in deeper water.Peer Reviewe