514 research outputs found
The toll of the automobile
Animal-vehicle collisions are a common phenomenon worldwide, causing injury or death to millions of animals and hundreds of human passengers each year. Collision numbers can be significant to species conservation, wildlife management, traffic safety, as well as from an economic and political point of view, and should thus be evaluated from these different perspectives. In this thesis, I assess, evaluate, analyse and predict animal-vehicle collisions with respect to their extent, their effect on populations, and their broad and fine scale distribution. A questionnaire with Swedish drivers indicated that nationwide road traffic in 1992 may caused an annual loss in harvest of common game species of 7% to 97% and of 1% to 12% of estimated populations. Road mortality did not appear as an existential threat to most species, although in badgers (Meles meles), traffic probably is the largest single cause of death. A slow population growth rate coupled with a high proportion of adult badger road-kills is responsible for their sensitivity to road mortality. Provided that road mortality is additive, we predicted that losses due to nationwide traffic might already exceed birth rates and limit badger population growth. In roe deer (Capreolus capreolus) and moose (Alces alces), road mortality is of minor importance to the population. Broad-scale trends and patterns in collision numbers correlate with harvest and traffic volumes, thus providing a simple means to monitor the toll of road traffic. To predict local collision risks with these species, information on animal abundance and landscape composition, on road traffic parameters, and on the spatial coincidence of roads and landscape elements is needed. However, vehicle speed appeared as one of the most important factors determining collision risks with moose, underlining the influence of human factors on collision risks. Successful counteraction therefore requires an interdisciplinary approach that addresses both the animal and the driver in their shared environment
Overview of CLEF NEWSREEL 2014: News Recommendations Evaluation Labs
This paper summarises objectives, organisation, and results of the first
news recommendation evaluation lab (NEWSREEL 2014). NEWSREEL targeted
the evaluation of news recommendation algorithms in the form of a campaignstyle
evaluation lab. Participants had the chance to apply two types of evaluation
schemes. On the one hand, participants could apply their algorithms onto a data
set. We refer to this setting as off-line evaluation. On the other hand, participants
could deploy their algorithms on a server to interactively receive recommendation
requests. We refer to this setting as on-line evaluation. This setting ought to reveal
the actual performance of recommendation methods. The competition strived to
illustrate differences between evaluation with historical data and actual users. The
on-line evaluation does reflect all requirements which active recommender systems
face in practise. These requirements include real-time responses and large-scale
data volumes. We present the competition’s results and discuss commonalities
regarding participants’ approaches
Translating Middle English (Im)politeness: The Case of Geoffrey Chaucer’s Miller’s Tale
Some of the bawdy details of Chaucer’s Canterbury Tales continue to pose challenges to translators, who must find renderings that are both descriptively and stylistically adequate. The Miller’s Tale provides an illustrative case study, in which the drunken narrator describes Nicholas’s rather physical wooing of the carpenter’s wife Alisoun in graphic detail. Existing translations of the key term queynte range from the flowery euphemism to the straightforward vulgarism. An appropriate translation into present-day English needs to be based not only on sound philological analysis, but also on a careful evaluation of the register of the original Middle English expression. This article offers a corpus-based assessment of relevant candidate expressions in order to propose a translation that captures the appropriate level of (im)politeness, both of the narrator towards his fellow pilgrims and of Chaucer towards his readers
Tissue Engineering mit Hyaluronsäure-Gelatine-Kompositmatrices zusätzlich stabilisiert mit Gelatine und Transglutaminase
Das Tissue Engineering im Bereich avaskulärer Meniskusläsionen beinhaltet eine in vitro Kultivierung und Differenzierung von autologen Zellen in einem Scaffold und die anschließende Implantation in den Meniskusdefekt.
Eine im eigenen Labor als solches Scaffold entwickelte Hyaluronsäure-Gelatine-Komposit-Matrix soll durch zusätzliches Einbringen von Gelatine und Transglutaminase mechanisch stabilisiert werden.
Zur Messung der Stabilität der mit Transglutaminase enzymatisch quervernetzten Gelatine bestimmten wir unter anderem einen Wert für die Arbeit zur Kompression des Gels in einer Well-Platte mit Hilfe eines umfunktionierten Infusiomaten und eines ausgesuchten Stempels. Außerdem erfolgten Kompressionen von freien Gel-Zylindern und Matrices – bei Messung der Matrices zusätzlich auch Zugbelastungen.
Zur Bestimmung der enzymatischen Aktivität bevorzugten wir eine Fluoreszenz-Messung mit Kasein und Dansylcadaverin als Substrate. Unter Verwendung einer Meerschweinchentransglutaminase von Sigma als Standardtransglutaminase konnten wir die Aktivität der Transglutaminasen dosieren und unter verschiedenen Einflussfaktoren überprüfen.
Für die meisten mechanischen Versuche verwendeten wir eine bakterielle Transglutaminase von Ajinomoto.
Um eine möglichst feste Gelstruktur herzustellen, erwies es sich als vorteilhaft, die enzymatische Quervernetzung für mindestens 24 Stunden bei 4 °C stattfinden zu lassen.
Eine bis zu 24-stündige Kälteexposition der mesenchymalen Stammzellen in Form einer 3-D-Kultur in der quervernetzten Gelatine stellte bei 28-tägiger Nachbeobachtung keine relevante negative Auswirkung auf die Überlebensrate und das metabolische Wachstum dar. Eine Zellproliferation zeigte sich bei allen Gruppen unabhängig von der Kälteexposition kaum. Die Zellmorphologie zeigte die Ausbildung von Pseudopodien. Nach 28 Tagen ergaben sich Hinweise für eine osteogene Differenzierung. Insgesamt konnten die Zellen gut und in homogener Anordnung in der Gelatine stabilisiert werden.
Weitere Einflussfaktoren, wie die Konzentrationen der Gelatine, der Transglutaminase, des bei Ajinomoto enthaltenden Maltodextrin-Zucker und des fetalen bovinen Serum zeigten bei höheren Konzentrationen keine negativen, sondern zum Teil sogar positive Auswirkungen auf Zellvitalität und –wachstum.
Das Einbringen einer Gelatine-Transglutaminase-Lösung in die Poren der Hyaluronsäure-Gelatine-Komposit-Matrix und die anschließende Inkubation bei 4°C zeigte eine erhebliche Verbesserung der mechanischen Stabilität bei Kompression und Zugbelastung, sogar noch verstärkt durch zusätzliche Vorbehandlung der Matrices mit Transglutaminase, so dass eine zusätzliche Dosis von Transglutaminase an die Matrix vorweg adhärieren konnte.
Bei Kompressionen konnte etwa eine Verzehnfachung des E-Modul erreicht werden. Die maximale Zugbelastung konnte ungefähr verdoppelt werden. Die Zugdehnung wurde ebenfalls verbessert.
Insgesamt konnte festgehalten werden, dass durch die Einbringung von quervernetzter Gelatine eine Verbesserung von Materialeigenschaften gelang, die bei den herkömmlichen Matrices unbefriedigend waren.
Höhere Konzentrationen von Gelatine und Transglutaminase als die von uns gewählten maximalen Konzentrationen von 5% bzw. 3 U/ml wären wünschenswert, stellten allerdings ein Handhabungsproblem dar, insbesondere in Bezug auf das rechtzeitige Einbringen der Gelatine-Transglutaminase-Lösung in die Matrix vor dem Zäh-Werden und schließlich Hart-Werden der Lösung
Benchmarking news recommendations: the CLEF NewsREEL use case
The CLEF NewsREEL challenge is a campaign-style evaluation lab allowing participants to evaluate and optimize news recommender algorithms. The goal is to create an algorithm that is able to generate news items that users would click, respecting a strict time constraint. The lab challenges participants to compete in either a "living lab" (Task 1) or perform an evaluation that replays recorded streams (Task 2). In this report, we discuss the objectives and challenges of the NewsREEL lab, summarize last year's campaign and outline the main research challenges that can be addressed by participating in NewsREEL 2016
CLEF NewsREEL 2016: Comparing Multi-Dimensional Offline and Online Evaluation of News Recommender Systems
Running in its third year at CLEF, NewsREEL challenged participants
to develop news recommendation algorithms and have them benchmarked in
an online (Task 1) and offline setting (Task 2), respectively. This paper provides
an overview of the NewsREEL scenario, outlines this year’s campaign, presents
results of both tasks, and discusses the approaches of participating teams. Moreover,
it overviews ideas on living lab evaluation that have been presented as part
of a “New Ideas” track at the conference in Portugal. Presented results illustrate
potentials for multi-dimensional evaluation of recommendation algorithms in
a living lab and simulation based evaluation setting
α- and β-Adrenergic receptor mechanisms in spontaneous contractile activity of rat ileal longitudinal smooth muscle
Gastrointestinal motility is influenced by adrenergic modulation. Our aim was to identify specific subtypes of adrenergic receptors involved in inhibitory mechanisms that modulate gut smooth muscle contractile activity. Muscle strips of rat ileal longitudinal muscle were evaluated for spontaneous contractile activity and for equimolar dose-responses (10-7 to 3 x 10-5 M) to the adrenergic agents norepinephrine (nonselective agonist), phenylephrine (α1-agonist), clonidine (α2-agonist), prenalterol (β1-agonist), ritodrine (β2- agonist), and ZD7114 (β3-agonist) in the presence and absence of tetrodotoxin (nonselective nerve blocker). Norepinephrine (3 x 10-5 M) inhibited 65 ± 6% (mean ± SEM) of spontaneous contractile activity. The same molar dose of ritodrine, phenylephrine, or ZD7114 resulted in less inhibition (46 ±7%, 31 ± 5%, and 39 ± 3%, respectively; P < 0.05). The calculated molar concentration of ZD7114 needed to induce 50% inhibition was similar to that of norepinephrine, whereas higher concentrations of phenylephrine or ritodrine were required. Clonidine and prenalterol had no effect on contractile activity. Blockade of intramural neural transmission by tetrodotoxin affected the responses to ritodrine and phenylephrine (but not to norepinephrine or ZD7114), suggesting that these agents exert part of their effects via neurally mediated enteric pathways. Our results suggest that adrenergic modulation of contractile activity in the rat ileum is mediated primarily by muscular β3-, β2-, and α1 -receptor mechanisms; the latter two also involve neural pathway
Native Valve Infective Endocarditis in Elderly and Younger Adult Patients: Comparison of Clinical Features and Outcomes with Use of the Duke Criteria
Role of Selective α and β Adrenergic Receptor Mechanisms in Rat Jejunal Longitudinal Muscle Contractility
Gut motility is modulated by adrenergic mechanisms. The aim of our study was to examine mechanisms of selective adrenergic receptors in rat jejunum. Spontaneous contractile activity of longitudinal muscle strips from rat jejunum was measured in 5-ml tissue chambers. Dose-responses (six doses, 10−7-3 × 10−5M) to norepinephrine (NE, nonspecific), phenylephrine (PH, α1), clonidine (C, α2), prenalterol (PR, β1), ritodrine (RI, β2), and ZD7714 (ZD, β3) were evaluated with and without tetrodotoxin (TTX, nerve blocker). NE(3 × 10−5M) inhibited 74 ± 5% (mean ± SEM) of spontaneous activity. This was the maximum effect. The same dose of RI(β2), PH(α1), or ZD(β3) resulted in an inhibition of only 56 ± 5, 43 ± 4, 33 ± 6, respectively. The calculated concentration to induce 50% inhibition (EC50) of ZD(β3) was similar to NE, whereas higher concentrations of PH(α1) or RI(β2) were required. C(α2) and PR(β1) had no effect. TTX changed exclusively the EC50 of RI from 4.4 ± 0.2 to 2.7 ± 0.8% (p < 0.04). Contractility was inhibited by NE (nonspecific). PH(α1), RI(β2), and ZD(β3) mimic the effect of NE. TTX reduced the inhibition by RI. Our results suggest that muscular α1, β2, and β3 receptor mechanisms mediate adrenergic inhibition of contractility in rat jejunum. β2 mechanisms seem to involve also neural pathway
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