808 research outputs found
Trapping black hole remnants
Large extra dimensions lower the Planck scale to values soon accessible. The production of TeV mass black holes at the LHC is one of the most exciting predictions. However, the final phases of the black hole's evaporation are still unknown and there are strong indications that a black hole remnant can be left. Since a certain fraction of such objects would be electrically charged, we argue that they can be trapped. In this paper, we examine the occurrence of such charged black hole remnants. These trapped remnants are of high interest, as they could be used to closely investigate the evaporation characteristics. Due to the absence of background from the collision region and the controlled initial state, the signal would be very clear. This would allow to extract information about the late stages of the evaporation process with high precision
Black Hole Remnants at the LHC
Within the scenario of large extra dimensions, the Planck scale is lowered to
values soon accessible. Among the predicted effects, the production of TeV mass
black holes at the {\sc LHC} is one of the most exciting possibilities. Though
the final phases of the black hole's evaporation are still unknown, the
formation of a black hole remnant is a theoretically well motivated
expectation. We analyze the observables emerging from a black hole evaporation
with a remnant instead of a final decay. We show that the formation of a black
hole remnant yields a signature which differs substantially from a final decay.
We find the total transverse momentum of the black hole event to be
significantly dominated by the presence of a remnant mass providing a strong
experimental signature for black hole remnant formation
Electronic Health Records: An International Perspective on "Meaningful Use"
Examines the extent of meaningful use of electronic health records in Denmark, New Zealand, and Sweden, including sharing information with organizations, health authorities, and patients. Outlines challenges of and insights into encouraging U.S. adoption
(Self-)evaluation of computer competence: how gender matters
Is the negative stereotype of women with regard to computer competence still exerting power in our society? In this study, 206 participants observed a target person (either a woman or a man) on a video who was about to solve a complex computer task. Participants had to estimate whether the target person was successful on this task in a limited amount of time. After they had received the information that the target person had solved the task successfully in the required time period, and that the person’s performance was above average, they were asked to provide a reason for the success (luck vs. skill attribution) and to evaluate the general computer competence of the target. Then, participants had to evaluate their own (hypothetical) computer competence in comparison to the target. Results suggest that for the direct evaluation of the target persons and for the causal attribution of success, no systematic gender-related biases occurred. In the self-ratings of participants; however, findings showed that (a) women judged their computer competence to be lower than did men, and (b) both women and men judged their own hypothetical performance in the computer-related task to be relatively higher when comparing it to the identically scripted performance of a woman vs. a man
Augmenting Biogas Process Modeling by Resolving Intracellular Metabolic Activity
The process of anaerobic digestion in which waste biomass is transformed to methane by complex microbial communities has been modeled for more than 16 years by parametric gray box approaches that simplify process biology and do not resolve intracellular microbial activity. Information on such activity, however, has become available in unprecedented detail by recent experimental advances in metatranscriptomics and metaproteomics. The inclusion of such data could lead to more powerful process models of anaerobic digestion that more faithfully represent the activity of microbial communities. We augmented the Anaerobic Digestion Model No. 1 (ADM1) as the standard kinetic model of anaerobic digestion by coupling it to Flux-Balance-Analysis (FBA) models of methanogenic species. Steady-state results of coupled models are comparable to standard ADM1 simulations if the energy demand for non-growth associated maintenance (NGAM) is chosen adequately. When changing a constant feed of maize silage from continuous to pulsed feeding, the final average methane production remains very similar for both standard and coupled models, while both the initial response of the methanogenic population at the onset of pulsed feeding as well as its dynamics between pulses deviates considerably. In contrast to ADM1, the coupled models deliver predictions of up to 1,000s of intracellular metabolic fluxes per species, describing intracellular metabolic pathway activity in much higher detail. Furthermore, yield coefficients which need to be specified in ADM1 are no longer required as they are implicitly encoded in the topology of the species’ metabolic network. We show the feasibility of augmenting ADM1, an ordinary differential equation-based model for simulating biogas production, by FBA models implementing individual steps of anaerobic digestion. While cellular maintenance is introduced as a new parameter, the total number of parameters is reduced as yield coefficients no longer need to be specified. The coupled models provide detailed predictions on intracellular activity of microbial species which are compatible with experimental data on enzyme synthesis activity or abundance as obtained by metatranscriptomics or metaproteomics. By providing predictions of intracellular fluxes of individual community members, the presented approach advances the simulation of microbial community driven processes and provides a direct link to validation by state-of-the-art experimental techniques
Der Zackenstil in der Monumentalmalerei am Niederrhein
Es ist Ziel und Resultat der vorliegenden Arbeit, einen alternativen Weg des Stiltransfers von Byzanz nach Nordwestdeutschland aufzuzeigen. Seit etwa 100 Jahren hat kunsthistorische Forschung ausschließlich einen Weg von Byzanz über Sachsen nach Köln ihren Untersuchungen zugrunde gelegt. Es konnte gezeigt werden, dass das normannische Sizilien und und weitere Länder unter normannischer Herrschaft einen bedeutenden Anteil an der Weitergabe byzantinischer Stilimpulse an den Niederrhein gehabt haben
Stärkung der Ertragssicherheit und Rentabilität im biologischen Erdbeeranbau durch effektivere Unkrautkontrolle sowie Regulierung des Erdbeerblütenstechers und verschiedener Wurzelfäulen
Der ökologische Erdbeeranbau ist mit hohen Ertragsschwankungen und den daraus resultierenden Ertragsunsicherheiten konfrontiert, wodurch die Rentabilität dieses Betriebszweiges immer wieder in Frage gestellt wird. Die nach wie vor bestehende Unkrautproblematik, der Erdbeerblütenstecher (Anthonomus rubi) und verschiedene Wurzelfäulen wie die Vertcillium-Welke stellen mit die wichtigsten Ursachen für die Ertragsunsicherheit dar. Zur Unkrautkontrolle konnten durch den Fingerhackeeinsatz deutliche Arbeitszeiteinsparungen zur Handhacke dokumentiert werden, so dass auch für Flächen ab bereits 0,5 ha eine kostengünstige und höchst effektive Technik zur Verfügung steht. Die sensorgesteuerte Hacktechnik arbeitet ebenfalls höchst effektiv, zielt jedoch mehr auf größere Spezialbetriebe ab. Zum Erdbeerblütenstecher in einjährigen Beständen in der Sorte Malwina konnte der Befall durch verschiedene Netzauflagen signifikant gesenkt werden, jedoch blieb der ertragssteigernde Effekt der Klasse 1-Früchte aus. Stattdessen stiegen die Anteile der Klasse 2-Früchten überwiegend signifikant an, was sich durch den erhöhten Klimastress, die erschwerte Bestäubungssituation und mögliche mechanische Beschädigungen der Blüte zur Netzauflage erklären lässt. In zweijährigen Beständen konnte mit dem entomopathogenen Pilz Metarhizium anisopliae Isolat Ma43 keine signifikante Befallsreduktion erreicht werden, jedoch konnte in einem Vorversuch eine signifikante Ertragssteigerung dokumentiert werden. Zur Verticillium-Welke wurden auf einem stark belasteten und leichten Standort Antagonisten und Bodenhilfsstoffe in der Sorte Sonata untersucht. Promot WP und die zwei Bodenhilfsstoffe VermiGrand und Eifelgold führten zu keiner praxisrelevanten Ertragssteigerung, während RhizoVital 42, RhizoStar und Plantasalva geringere Erträge aufwiesen als die Kontrolle. Auf einem stark verticilliumbelasteten Standort wurden elf Erdbeersorten auf ihre Robustheit untersucht.
Positive Entwicklungen im Vergleich zur verticilliumempfindlichen Honeoye zeigten die Sorten Ultyma, Dely, Christine und Elianny. Unter dem Niveau von Honeoye lagen die Sorten Fenella und Candiss
Women and computers: effects of stereotype threat on attribution of failure
This study investigated whether stereotype threat can influence women’s attributions of failure in a computer
task. Male and female college-age students (n = 86, 16–21 years old) from Germany were asked to work on a computer task and were hinted beforehand that in this task, either (a) men usually perform better than women do (negative threat condition), or (b) women usually perform better than men do (positive condition), or (c) they received no threat or gender-related information (control group). The final part of the task was prepared to provide an experience of failure: due to a faulty USB-memory stick, completion of the task was not possible. Results suggest a stereotype threat effect on women’s attribution of failure: in the negative threat condition, women attributed the failure more internally (to their own inability), and men more externally (to the faulty technical equipment). In the positive and control conditions, no significant gender differences in attribution emerged
"Doing and Viewing Gender" : a lens-model approach to the communicative construction of gender in task-oriented groups
Within the framework of the current gender research this dissertation focuses on applying a joint model and a corresponding method suited for integrating the many dispersed empirical studies on doing and viewing aspects of gender. An application of Brunswik’s lens-model (Brunswik, 1956) to communication research provides the basis for the development of a "performance and perception"-method that allows for an assessment of gender construction on a concrete and observation-based cue level. Additionally, this research contributes to the investigation of one of the most important applied questions of high societal relevance in gender research: why are there such few women in organizational leadership positions despite their high amount of professional qualification? A communication perspective to approach this question was chosen, focusing on verbal and nonverbal communication in task-oriented small groups. The research provides an overview of theoretical approaches within social psychology, a review of empirical literature, and a description of a series of six studies (N=391), conducted to approach the applied question and to test the new method of assessing gender construction processes. The research demonstrates the power of expectations over behavioral evidence of identical performance information (constructive effects). Results depended on the gender hypothesis and on real gender but also on the sex of the participant, sympathy, and other factors. In fact, gender hypothesis explained but a small amount of the variance of the overall findings and the magnitude of gender effects was generally small. Results of verbal and nonverbal cue analyses indicated that participants used semiotic cues differently, depending on their own gender, their gender-hypothesis and the concept in question. For example, in Study 1 women used more syntactic cues and men more pragmatic cues, while both used the same amount of semantic cues to infer gender of their chat mates. However, syntactic cues had the highest predictive value, followed by pragmatic cues, whereas semantic cues left participants at chance level of guessing gender correctly. In sum, cue analysis shed more light on communicative processes than the mere use of rating scales. Taken together, the research provides a useful framework and theory-based methodology for current empirical work, applying Brunswik’s lens model to gender communication research. The novelty of the empirical work lies in (a) the application of the performance and perception method in a CMC context, (b) the outline of and investigation into the new concept of "evaluative affect display" as a general indicator of approval or disapproval, and a specific indicator of prejudice toward female leaders, in small task-oriented groups, and (c) the use of dynamic interactional material within the Goldberg-paradigm, making the perceptual situation more realistic than by just using the previously employed written text materials. Both, gender-assumption and real gender of leaders had cognitive, expectational, and behavioral implications, but were not the only factors influencing performance and perception processes. Thus, gender construction processes are a highly context-sensitive phenomenon dependent on attributes of the perceiver, the target, and the respective degree of gender salience in a given situation. Applying Brunswik's lens-model to gender communication research generated a new method which allows to more specifically assess behavioral cues implied in gender communication
Retrospective checking of compliance with practice guidelines for acute stroke care: a novel experiment using openEHR’s Guideline Definition Language
BACKGROUND: Providing scalable clinical decision support (CDS) across institutions that use different electronic health record (EHR) systems has been a challenge for medical informatics researchers. The lack of commonly shared EHR models and terminology bindings has been recognised as a major barrier to sharing CDS content among different organisations. The openEHR Guideline Definition Language (GDL) expresses CDS content based on openEHR archetypes and can support any clinical terminologies or natural languages. Our aim was to explore in an experimental setting the practicability of GDL and its underlying archetype formalism. A further aim was to report on the artefacts produced by this new technological approach in this particular experiment. We modelled and automatically executed compliance checking rules from clinical practice guidelines for acute stroke care. METHODS: We extracted rules from the European clinical practice guidelines as well as from treatment contraindications for acute stroke care and represented them using GDL. Then we executed the rules retrospectively on 49 mock patient cases to check the cases’ compliance with the guidelines, and manually validated the execution results. We used openEHR archetypes, GDL rules, the openEHR reference information model, reference terminologies and the Data Archetype Definition Language. We utilised the open-sourced GDL Editor for authoring GDL rules, the international archetype repository for reusing archetypes, the open-sourced Ocean Archetype Editor for authoring or modifying archetypes and the CDS Workbench for executing GDL rules on patient data. RESULTS: We successfully represented clinical rules about 14 out of 19 contraindications for thrombolysis and other aspects of acute stroke care with 80 GDL rules. These rules are based on 14 reused international archetypes (one of which was modified), 2 newly created archetypes and 51 terminology bindings (to three terminologies). Our manual compliance checks for 49 mock patients were a complete match versus the automated compliance results. CONCLUSIONS: Shareable guideline knowledge for use in automated retrospective checking of guideline compliance may be achievable using GDL. Whether the same GDL rules can be used for at-the-point-of-care CDS remains unknown
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