Refine
Year of publication
- 2014 (1208) (remove)
Document Type
- Article (583)
- Part of Periodical (163)
- Working Paper (149)
- Book (134)
- Doctoral Thesis (86)
- Report (27)
- Part of a Book (23)
- Conference Proceeding (18)
- Review (10)
- Preprint (7)
Language
- English (1208) (remove)
Keywords
- taxonomy (21)
- new species (19)
- Syntax (11)
- Inversionsfigur (10)
- Multistability (10)
- Multistable figures (10)
- Wahrnehmungswechsel (10)
- morphology (8)
- Bantusprachen (7)
- Benjamin, Walter (7)
Institute
- Medizin (228)
- Wirtschaftswissenschaften (149)
- Center for Financial Studies (CFS) (131)
- Physik (100)
- Biowissenschaften (88)
- Sustainable Architecture for Finance in Europe (SAFE) (86)
- House of Finance (HoF) (82)
- Biochemie und Chemie (48)
- Geowissenschaften (41)
- Gesellschaftswissenschaften (33)
The neutron sensitivity of the C6D6 detector setup used at n_TOF facility for capture measurements has been studied by means of detailed GEANT4 simulations. A realistic software replica of the entire n_TOF experimental hall, including the neutron beam line, sample, detector supports and the walls of the experimental area has been implemented in the simulations. The simulations have been analyzed in the same manner as experimental data, in particular by applying the Pulse Height Weighting Technique. The simulations have been validated against a measurement of the neutron background performed with a natC sample, showing an excellent agreement above 1 keV. At lower energies, an additional component in the measured natC yield has been discovered, which prevents the use of natC data for neutron background estimates at neutron energies below a few hundred eV. The origin and time structure of the neutron background have been derived from the simulations. Examples of the neutron background for two different samples are demonstrating the important role of accurate simulations of the neutron background in capture cross-section measurements.
The spitting spider Scytodes fusca Walckenaer, 1837 is recorded for the first time in Central Europe from both Germany and Slovakia. The species was found in two localities, within the Botanical Garden in Bratislava (Slovakia), specifically from a heated greenhouse with high humidity, and the "Tropical Islands", a tropical holiday resort in Krausnick (Germany). It seems that this Pantropical species has probably been introduced here along with imported plants. A description of diagnostic characters, as well as figures, is given.
Carinostoma elegans new to the Slovakian harvestmen fauna (Opiliones, Dyspnoi, Nemastomatidae)
(2014)
A new genus and species of small harvestman was found for the first time in Slovakia – Carinostoma elegans (Sorensen, 1894). One male and two females were collected in the Mlyňany arboretum of the Slovak Academy of Science (western Slovakia). Descriptions and photographs of both sexes of C. elegans are provided. Additional comments, and a map of distribution of all species of this genus, are provided.
The measurement of dielectrons (electron-positron pairs) allows to investigate the properties of strongly interacting matter, in particular the Quark-Gluon Plasma (QGP), which is created in relativistic heavy-ion collisions at the LHC. The evolution of the collision can be probed via dielectrons since electrons do not interact strongly and are created during all stages of the collision. One of the interests in dielectron measurements is motivated by possible modifications of the electromagnetic emission spectrum in the QGP, where pp collisions are used as a medium-free reference. The dielectron spectrum consists of contributions from various processes. In order to estimate contributions of known dielectron sources, simulations of the so-called dielectron cocktail are performed. In this thesis, dielectron cocktails in minimum bias pp collisions at p s = 7 TeV, p–Pb collisions at p sNN = 5.02 TeV and in central (0-10%) and semi-central (20-50%) Pb–Pb collisions at p sNN = 2.76 TeV at the LHC are presented.
Imitation paradigms are used in various domains of developmental psychological research to assess various cognitive processes such as memory (deferred imitation), action perception and action understanding (mainly direct imitation), as well as categorization and learning about objects (deferred imitation with a change in target objects and generalized imitation). Although these processes are most likely not independent from each other, their relations are still largely unclear. On the one hand, deferred imitation studies have shown that infants' performance improves with increasing age, resulting in the reproduction of more target actions after longer delay intervals. On the other hand, imitation studies focusing on infants' action understanding have found that infants do not necessarily imitate the model's exact actions – actions or action steps that seem to be irrational or irrelevant are omitted by infants under certain circumstances (selective imitation). Additionally, findings of imitation studies that require a transfer of the target actions to novel objects have demonstrated that infants do not only learn about actions, but also about objects, when they engage in imitation.
The present dissertation aims at integrating different perspectives of imitation research by testing 12- and 18-month-old infants in deferred imitation tests consisting of functional vs. arbitrary target actions, and by combining deferred imitation with eye tracking in half of the experiments. A deferred imitation paradigm was chosen to assess memory performance. Systematic variation of target action characteristics enabled the assessment of infants' imitation pattern, i.e., if they would imitate one kind of target actions more frequently than the other. Functionality was chosen as the action characteristic in focus because function is an object's most important property, thus this variation might shed some light on infants' learning about objects in the context of an imitation test. The main goal of the eye tracking experiments was to tackle the relations between infants' visual attention to, and deferred imitation of, different kinds of target actions.
The behavioral experiments revealed that both 12- and 18-month-olds imitated significantly more functional than arbitrary target actions after a delay of 30 minutes. In addition, while 12-month-olds showed a memory effect only for functional actions, 18-month-olds showed a memory effect for both kinds of actions. Thus, 12-month-olds imitated strictly selectively, and 18-month-olds imitated more exactly. This shows that the well established memory effect is modulated by target action functionality, which affects 12- and 18-month-olds' imitation differently. Furthermore, when retested after a two weeks delay, 18-month-olds' performance rates of functional and arbitrary target actions decreased parallel. This suggests that selective imitation is not affected by the duration of the retention interval, and that selection of target actions takes place at an earlier stage of action perception and memory processes.
In the eye tracking experiments, both 12- and 18-month-olds' imitation patterns replicated the findings of the behavioral experiments, showing consistently higher imitation rates of functional than arbitrary target actions. Contrary to this, infants' fixation times to the target actions were not affected by target action functionality. This contrast was supported by statistical analyses that found no clear correspondence between visual attention to and deferred imitation of target actions. This suggests that selective imitation cannot be explained by selective visual attention. Nevertheless, finer-grained analyses of gaze and imitation data in the 18 months old group suggested that infants' increased attention to the social-communicative context of the imitation task was related to more exact imitation, i.e. imitation of not only functional, but also arbitrary target actions.
The findings are discussed against the background of imitation theories, with regard to the relations between different cognitive processes underlying infants' imitation, such as memory, action perception and learning about objects.
Croatian negative indefinite expressions, or the so-called ni-words, are complex forms made by adding the prefix ni- to simple forms of indefinite pronouns. The Croatian standard norm prescribes that in prepositional phrases involving negative idefinite pronouns (the so-called ni-pronouns), the negative element ni should be separated from the pronoun and put in front of the preposition. However, in everyday communication one may often notice the use of the word order P + negative indefinite pronoun, and this word order has also made its way into newspapers and other media. This paper attempts to determine whether there is a significant difference in meaning between the order ni + P + indefinite pronoun and the order P + negative indefinite pronoun to account for such a change in language. We also analyze the frequency of use of these two different word orders in the Croatian National Corpus, examining eleven most frequent prepositions and six simple indefinite pronouns.
BACKGROUND: Transient episodes of ischemia in a remote organ or tissue (remote ischemic preconditioning, RIPC) can attenuate myocardial injury. Myocardial damage is associated with tissue remodeling and the matrix metalloproteinases 2 and 9 (MMP-2/9) are crucially involved in these events. Here we investigated the effects of RIPC on the activities of heart tissue MMP-2/9 and their correlation with serum concentrations of cardiac troponin T (cTnT), a marker for myocardial damage.
METHODS: In cardiosurgical patients with cardiopulmonary bypass (CPB) RIPC was induced by four 5 minute cycles of upper limb ischemia/reperfusion. Cardiac tissue was obtained before as well as after CPB and serum cTnT concentrations were measured. Tissue derived from control patients (N = 17) with high cTnT concentrations (≥0.32 ng/ml) and RIPC patients (N = 18) with low cTnT (≤0.32 ng/ml) was subjected to gelatin zymography to quantify MMP-2/9 activities.
RESULTS: In cardiac biopsies obtained before CPB, activities of MMP-2/9 were attenuated in the RIPC group (MMP-2: Control, 1.13 ± 0.13 a.u.; RIPC, 0.71 ± 0.12 a.u.; P < 0.05. MMP-9: Control, 1.50 ± 0.16 a.u.; RIPC, 0.87 ± 0.14 a.u.; P < 0.01), while activities of the pro-MMPs were not altered (P > 0.05). In cardiac biopsies taken after CPB activities of pro- and active MMP-2/9 were not different between the groups (P > 0.05). Spearman's rank tests showed that MMP-2/9 activities in cardiac tissue obtained before CPB were positively correlated with postoperative cTnT serum levels (MMP-2, P = 0.016; MMP-9, P = 0.015).
CONCLUSIONS: Activities of MMP-2/9 in cardiac tissue obtained before CPB are attenuated by RIPC and are positively correlated with serum concentrations of cTnT. MMPs may represent potential targets for RIPC mediated cardioprotection.
TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00877305.
Reduction and deletion processes occur regularly in conversational speech. A segment that is affected by such reduction and deletion processes in many Germanic languages (e.g., Dutch, English, German) is /t/. There are similarities concerning the factors that influence the likelihood of final /t/ to get deleted, such as segmental context. However, speakers of different languages differ with respect to the acoustic cues they leave in the speech signal when they delete final /t/. German speakers usually lengthen a preceding /s/ when they delete final /t/. This article investigates to what extent German listeners are able to reconstruct /t/ when they are presented with fragments of words where final /t/ has been deleted. It aims also at investigating whether the strategies that are used by German depend on the length of /s/, and therefore whether listeners are using language-specific cues. Results of a forced-choice segment detection task suggest that listeners are able to reconstruct deleted final /t/ in about 45% of the times. The length of /s/ plays some role in the reconstruction, however, it does not explain the behavior of German listeners completely.
This paper is the first to conduct an incentive-compatible experiment using real monetary payoffs to test the hypothesis of probabilistic insurance which states that willingness to pay for insurance decreases sharply in the presence of even small default probabilities as compared to a risk-free insurance contract. In our experiment, 181 participants state their willingness to pay for insurance contracts with different levels of default risk. We find that the willingness to pay sharply decreases with increasing default risk. Our results hence strongly support the hypothesis of probabilistic insurance. Furthermore, we study the impact of customer reaction to default risk on an insurer’s optimal solvency level using our experimentally obtained data on insurance demand. We show that an insurer should choose to be default-free rather than having even a very small default probability. This risk strategy is also optimal when assuming substantial transaction costs for risk management activities undertaken to achieve the maximum solvency level.
Halting biological invasions in Europe : from data to decisions ; a message from NEOBIOTA 2012
(2014)
The NEOBIOTA conferences initiated by the European Group on Biological Invasions represents a forum for exchange of ideas and discussion of topics related to biological invasions as well as an interface between science, application and policies (Kowarik and Starfinger 2009). The 7th NEOBIOTA conference (http://neobiota2012.blogspot.com.es/), held in Pontevedra (Spain) from 12–14 September 2012, brought together 288 participants (ecologists, conservationists, representatives of governmental agencies and stake-holders), from 24 European countries and 9 non-European ones (namely, Australia, Brazil, Canada, Chile, Colombia, New Zealand, South Africa, United States and Venezuela).
This dataset represents a registry of species that are not native but recorded to live in the wild of at least one of the four countries that comprise the Two Seas Area, i.e. Great Britain, France, Belgium and the Netherlands. For each of the 6,661 species, subspecies and hybrids listed, we provide detailed information on its status in each country, taxonomic affiliation and environment inhabited. The data were collected by review of 36 web- and print-based sources over an eight-month period. Further systematic scanning of three of the most relevant scientific journals, i.e. Neobiota, Aquatic Invasions and BioInvasions Records, recovered 19 additional relevant publications from which information was included in the registry. As a result, the registry will serve as a basis for developing effective, cross-boundary strategies to manage and control non-native species, which can have severe ecological and economic impacts. The registry can further be used as a general reference for both scientists and practitioners, as well as a tool to assess reliability and comprehensiveness of other well-known databases such as the DAISIE portal.
Plexins are widely expressed transmembrane proteins that mediate the cellular effects of semaphorins. The molecular mechanisms of plexin-mediated signal transduction are still poorly understood. Here we show that signalling via B-family plexins leading to the activation of the small GTPase RhoA requires activation of the IκB kinase (IKK)-complex. In contrast, plexin-B-dependent regulation of R-Ras activity is not affected by IKK activity. This regulation of plexin signalling depends on the kinase activity of the IKK-complex, but is independent of NF-κB activation. We confirm that the IKK-complex is active in tumour cells and osteoblasts, and we demonstrate that plexin-B-dependent tumour cell invasiveness and regulation of osteoblast differentiation require an active IKK-complex. This study identifies a novel, NF-κB-independent function of the IKK-complex and shows that IKK directs plexin-B signalling to the activation of RhoA.
Justice, not development : Sen and the hegemonic framework for ameliorating global inequality
(2014)
Starting from the merits of Sen's "Development as freedom", the article also explores its shortcomings. It argues that they are related to an uncritical adoption of the discourse of "development", which is the hegemonic framework for ameliorating global inequality today. This discourse implies certain limitations of thought and action, and the article points out three areas where urgent questions of global justice have been largely ignored by development theory and policy as a consequence. Struggles for justice on a global scale, this is the conclusion, should not take the detour of "development".
In the past sixty years, excessive water consumption and dam construction have significantly influenced natural flow regimes and surface freshwater ecosystems throughout China, and thus resulted in serious environmental problems. In order to balance the competing water demands between human and environment and provide knowledge on sustainable water management, assessments on anthropogenic flow alterations and their impacts on aquatic and riparian ecosystems in China are needed.
In this study, the first evaluation on quantitative relationships between anthropogenic flow alterations and ecological responses in eleven river basins and watersheds in China was performed based on the data that could be obtained from published case studies. Quantitative relationships between changes in average annual discharge, seasonal low flow and seasonal high flow and changes in ecological indicators (fish diversity, fish catch and vegetation cover, etc.) were analyzed. The results showed that changes in riparian vegetation cover as well as changes in fish diversity and fish catch were strongly correlated with the changes in flow magnitude (r = 0.77, 0.66), especially with changes in average annual river discharge. In addition, more than half of the variations in vegetation cover could be explained by changes in average annual river discharge (r² = 0.63) and roughly 50 % changes in fish catch in arid and semi-arid region and 60% changes of fish catch in humid region could be related to alterations in average annual river discharge (r² = 0.53, 0.58).
In a supplementary analysis of this study, the first estimation on quantitative relationships between decreases in native fish species richness and anthropogenic flow alterations in 34 river basins and sub-basins in China was conducted. Linear relationships between losses of native fish species and five ecologically relevant flow indicators were analyzed by single and multiple regression models. For the single regression analysis, significant linear relationships were detected for the indicators of long-term average annual discharge (ILTA) and statistical low flow Q90 (IQ90). For the multiple regressions, no indicator other than ILTA has significant relationships with changes in number of fish species mainly due to collinearity. Two conclusions emerged from the analysis: 1) losses of fish species were positively correlated with changes in ILTA in China and 2) indicator of ILTA was dominant over other flow indicators included in this research for the given dataset. These results provide a guideline for the sustainable water resources management in rivers with high risk of fish extinction in China.
The investigated haloarchaeal species, Halobacterium salinarum, Haloferax mediterranei, and H. volcanii, have all been shown to be polyploid. They contain several replicons that have independent copy number regulation, and most have a higher copy number during exponential growth phase than in stationary phase. The possible evolutionary advantages of polyploidy for haloarchaea, most of which have experimental support for at least one species, are discussed. These advantages include a low mutation rate and high resistance toward X-ray irradiation and desiccation, which depend on homologous recombination. For H. volcanii, it has been shown that gene conversion operates in the absence of selection, which leads to the equalization of genome copies. On the other hand, selective forces might lead to heterozygous cells, which have been verified in the laboratory. Additional advantages of polyploidy are survival over geological times in halite deposits as well as at extreme conditions on earth and at simulated Mars conditions. Recently, it was found that H. volcanii uses genomic DNA as genetic material and as a storage polymer for phosphate. In the absence of phosphate, H. volcanii dramatically decreases its genome copy number, thereby enabling cell multiplication, but diminishing the genetic advantages of polyploidy. Stable storage of phosphate is proposed as an alternative driving force for the emergence of DNA in early evolution. Several additional potential advantages of polyploidy are discussed that have not been addressed experimentally for haloarchaea. An outlook summarizes selected current trends and possible future developments.
Haloferax volcanii uses extracellular DNA as a source for carbon, nitrogen, and phosphorous. However, it can also grow to a limited extend in the absence of added phosphorous, indicating that it contains an intracellular phosphate storage molecule. As Hfx. volcanii is polyploid, it was investigated whether DNA might be used as storage polymer, in addition to its role as genetic material. It could be verified that during phosphate starvation cells multiply by distributing as well as by degrading their chromosomes. In contrast, the number of ribosomes stayed constant, revealing that ribosomes are distributed to descendant cells, but not degraded. These results suggest that the phosphate of phosphate-containing biomolecules (other than DNA and RNA) originates from that stored in DNA, not in rRNA. Adding phosphate to chromosome depleted cells rapidly restores polyploidy. Quantification of desiccation survival of cells with different ploidy levels showed that under phosphate starvation Hfx. volcanii diminishes genetic advantages of polyploidy in favor of cell multiplication. The consequences of the usage of genomic DNA as phosphate storage polymer are discussed as well as the hypothesis that DNA might have initially evolved in evolution as a storage polymer, and the various genetic benefits evolved later.
Taxonomic revision of North American Eusphalerum Kraatz, 1857 (Coleoptera, Staphylinidae, Omaliinae)
(2014)
The North American species of the genus Eusphalerum Kraatz (Coleoptera, Staphylinidae, Omaliinae) are revised. The taxonomic history, natural history, geographical distribution of the genus, characters, species groups, diversity, and biogeography of North American species are presented. Two main phylogenetic lineages and 13 species groups are provisionally recognized. The following new synonymies are proposed: Eusphalerum farrarae (Hatch, 1944) = E. lawrencei Hatch, 1957; Eusphalerum californicum (Fauvel, 1878) = E. atriventre (Casey, 1894), = E. nigerrimum (Casey, 1894), = E. gilvipenne (Casey, 1894), = E. dichroum (Fall, 1922), = E. bonnelli (Hatch, 1944), = E. lunae Hatch, 1957; Eusphalerum fraternum (Casey, 1894) = E. minskae (Hatch, 1944); Eusphalerum rugulosum (Mäklin, 1853) = E. grayae (Hatch, 1944); Eusphalerum orientale (Bernhauer, 1912) = E. frosti (Bernhauer, 1928). The following lectotypes are designated: E. subangulatum (Casey), E. californicum (Fauvel), E. gilvipenne (Casey), E. diversicolle (Casey), E. convexum (Fauvel), E. fraternum (Casey), E. horni (Fauvel), E. orientale (Bernhauer), E. pothos (Mannerheim), and E. punctatum (Casey). The following new species are described: Eusphalerum pilosum (California); E. klimaszewskii (British Columbia); E. chatzimanolisi (California); E. carolinensis (Kentucky, Missouri, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia); E. caterinoi (California); E. luteipes (California); E. thayeranum (Alberta, British Columbia, Idaho, Indiana (doubtful record), Oregon, Washington); E. margaretae (Tennessee); E. newtoni (British Columbia, Oregon, California); E. parvispiculum (California, Oregon); E. uncinatum (British Columbia, California, Oregon, Washington). Eusphalerum lapponicum (Mannerheim, 1830) is excluded from the North American fauna. The following new combination is proposed: Xylodromus segmentarius (Mäklin, 1852: 322) (ex Omalium), wrongly attributed to Eusphalerum in the literature. Omalium marginatum Say, 1832 is considered a doubtful species, probably not Eusphalerum. A key to the 27 recognized North American Eusphalerum species and a catalog of the species are provided.
A survey of spiders of the genus Scytodes Latreille, 1804 in Iran resulted in six species occurring in this country: Scytodes fusca Walckenaer, 1837, S. strandi Spassky, 1941, S. thoracica (Latreille, 1802), S. univittata Simon, 1882 and – recorded for the first time – S. arwa Rheims, Brescovit & van Harten, 2006 and S. makeda Rheims, Brescovit & van Harten, 2006. Illustrations of the newly recorded species and a key to all known Iranian species are presented.
We analyze the risk premium on bank bonds at origination with a special focus on the role of implicit and explicit public guarantees and the systemic relevance of the issuing institutions. By looking at the asset swap spread on 5,500 bonds, we find that explicit guarantees and sovereign creditworthiness have a substantial effect on the risk premium. In addition, while large institutions still enjoy lower issuance costs linked to the TBTF framework, we find evidence of enhanced market disciple for systemically important banks which face, since the onset of the financial crisis, an increased premium on bond placements.
Cryo-electron tomography provides a snapshot of the cellular proteome. With template matching, the spatial positions of various macromolecular complexes within their native cellular context can be detected. However, the growing awareness of the reference bias introduced by the cross-correlation based approaches, and more importantly the lack of a reliable confidence measurement in the selection of these macromolecular complexes, has restricted the use of these applications. Here we propose a heuristic, in which the reference bias is measured in real space in an analogous way to the R-free value in X-ray crystallography. We measure the reference bias within the mask used to outline the area of the template, and do not modify the template itself. The heuristic works by splitting the mask into a working and a testing area in a volume ratio of 9:1. While the working area is used during the calculation of the cross-correlation function, the information from both areas is explored to calculate the M-free score. We show using artificial data, that the M-free score gives a reliable measure for the reference bias. The heuristic can be applied in template matching and in sub-tomogram averaging. We further test the applicability of the heuristic in tomograms of purified macromolecules, and tomograms of whole Mycoplasma cells.