1,033 research outputs found
MINFLUX tracking of single fluorophore-labeled proteins with nanometer/millisecond spatio-temporal precision
Wachsende PrĂ€zision und zeitliche Auflösung bei der Beobachtung von Dynamiken sind von entscheidender Bedeutung fĂŒr die Erforschung zellulĂ€re Prozesse und Funktionen. Im Feld der höchstauflösenden Mikroskopie rĂŒcken dabei die Auswirkungen von Markern auf die Probe stĂ€rker in den Fokus, wobei deren individuelle EinflĂŒsse hĂ€ufig unvorhersehbar sind. Fluoreszierende MolekĂŒle stellen die bis heute minimalinvasivsten Marker dar, wurden jedoch wegen der limitierten Fluoreszenzphotonenrate fĂŒr Hochgeschwindigkeitsmessungen durch die Verwendung groĂer Beads, die bis heute die höchste rĂ€umliche und zeitliche PrĂ€zision bieten, weitestgehend ersetzt. MINFLUX lokalisiert, selbst bei geringer Anzahl von Fluoreszenzphotonen, einzelne MolekĂŒle mit Nanometer PrĂ€zision und bietet damit groĂes Potenzial fĂŒr deren Verfolgung. Im Rahmen dieser Arbeit wurden, mit Hilfe eines neuen interferometrischen MINFLUX-Mikroskops, die Trajektorien einzelner, fluoreszenzmarkierter Motorproteine mit \SI{3}{\nano\m} PrĂ€zision, Kilohertz Aufnahmerate und nur 20\,Fluoreszenzphotonen pro Messpunkt aufgezeichnet und damit die Messgeschwindigkeit kamerabasierter Einzel-Farbstoff-Studien um zwei GröĂenordnungen ĂŒbertroffen. Eine umfangreiche Untersuchung der Schritte und Subschritte des mit einem einzelnen Farbstoff markierten Motorproteins Kinesin-1, löste Details in dessen Laufverhalten auf, die bisher ausschlieĂlich durch Bead-Studien zugĂ€nglich waren und identifizierte so den umstrittenen ATP-Bindungszustand. Auf Grundlage dieser Ergebnisse erweist sich MINFLUX als eine wegweisende neue Technik fĂŒr die hochaufgelöste Untersuchung von Proteinbewegungen bei minimaler BeeintrĂ€chtigung des biologischen Systems
A Simplified Model of the Causation of Technological Unemployment
Also published in: âJan Tinbergen Selected Papersâ, edited by L.H. Klaassen, L.M. Koyck and H.J. Witteveen, Nort- Holland Publishing Company, Amsterdam, 1959, pp. 165-181The purpose of the present paper is to find the influence on employment
of some of the outstanding "data" (extra-economic determining
factor-). For this purpose, a simplified model has been constructed in
which these data and the chief economic variables find their places.
Since it is not intended to picture cyclic variations and causations, the
model may be called a "long-run model." It excludes some of the most
typical cyclical phenomena such as stock-exchange speculation and
the existence of small lags of all kinds which are of importance to the
explar~ationo f cyclcs but do not seen1 to be so for long-run developments.
Since the investigators were interested chiefly in studying the consequences
of technological development for employnlent and the consequences
of some of the best-known devices to improve employment,
spccial attention was given to the corresponding sections of economic
life.
Thc calculations have been made for the United States prewar structure
(using figures for 1910) and for the postwar pre-Roosevelt structure
(using averages for 1919-1932
Can the Balanced Scorecard Help in Designing Conference Calls? The Effect of Balanced Information Composition on the Cost of Capital
Most recent studies on conference calls focus on the costs for firms that can arise from the calls' open nature. We study the benefits of conference calls and hypothesize that firms could use the balanced scorecard concept as a framework for presenting the information (i.e. balanced information composition) in conference calls to lower the cost of capital. Our results show a negative association between a more balanced information composition in conference calls and a firm's cost of capital. Additional tests substantiate that the effect of such a balanced information composition on the cost of capital is driven by a reduction in information asymmetry. Overall, the findings suggest that firms can benefit from the balanced scorecard concept by using it as a framework for preparing their conference calls
Intelligent support for inquiry learning from images: a learning scenario and tool
Inquiry learning involves the learner acquiring new concepts and skills by means of carrying out an investigation. Some previous studies have looked into how these learning activities can be carried out on source materials, such as web documents, and the provision of appropriate scaffolding to guide the learning process. Here we consider how intelligent support can be provided to guide the learner in analysing source materials and building knowledge from their interpretation. An important feature of our case study is that the source materials are images, potentially having greater variation in how they are interpreted and therefore increasing the need for intelligent support. Intelligent support provided by our system can identify patterns and inconsistencies in the learnerâs interpretation and knowledge building, and offer recommendations based on comparison with a reference model. The recommendations derived from a reference model aim to guide the learner in reviewing and revising their interpretation of the images and the implications of these for their inferences, rather than directly providing a ârightâ or âwrongâ evaluation of their answer
Model-based estimation of in-car-communication feedback applied to speech zone detection
Modern cars provide versatile tools to enhance speech communication. While an
in-car communication (ICC) system aims at enhancing communication between the
passengers by playing back desired speech via loudspeakers in the car, these
loudspeaker signals may disturb a speech enhancement system required for
hands-free telephony and automatic speech recognition. In this paper, we focus
on speech zone detection, i.e. detecting which passenger in the car is
speaking, which is a crucial component of the speech enhancement system. We
propose a model-based feedback estimation method to improve robustness of
speech zone detection against ICC feedback. Specifically, since the zone
detection system typically does not have access to the ICC loudspeaker signals,
the proposed method estimates the feedback signal from the observed microphone
signals based on a free-field propagation model between the loudspeakers and
the microphones as well as the ICC gain. We propose an efficient recursive
implementation in the short-time Fourier transform domain using convolutive
transfer functions. A realistic simulation study indicates that the proposed
method allows to increase the ICC gain by about 6dB while still achieving
robust speech zone detection results.Comment: 5 pages, submitted to International Workshop on Acoustic Signal
Enhancement (IWAENC), Bamberg, Germany, 202
Tooth loss in Sjögren?s syndrome patients compared to age and gender matched controls
To analyze the prevalence and location of tooth loss in Sjögren?s syndrome (SS) patients and compare them with an age- and gender-matched control group. Dental charts and x-rays of 108 (SS) patients were retrieved from an academic dental center and special care dentistry department. For each SS patient, an age- and gender-matched non-SS patient was randomly selected. Medication, number of extractions and date and location of extractions were assessed. Differences between SS and non-SS patients were analyzed using Mann-Whitney U tests, Chi-square tests and Fisher?s exact tests. Significantly more SS patients were edentulous compared to the non-SS group (14.8% versus 1.9%, p = 0.001). SS patients had a 61% higher risk to have experienced one or more extractions than control patients. In the SS group, there was a non-significant tendency for more maxillary teeth to have been extracted than mandibular teeth (42:34). In the control group, the number of extractions in the maxilla and mandible were comparable (21:20). When divided into sextants, the number of SS patients with one or more extractions was significantly higher than for non-SS patients for each sextant (p = 0.001 to p = 0.032). The largest difference in the proportion of patients with one or more extractions between the SS and non-SS patients occurred in the upper anterior sextant (3.4 times more frequent). SS patients are more prone to experience dental extractions compared to patients without SS. It could be speculated that this is related to a decreased salivary secretion
Stories that Change Our World? Narratives of the Sustainable Economy
Narratives are shaping our understanding of the world. They convey values and norms and point to desirable future developments. In this way, they justify and legitimize political actions and social practices. Once a narrative has emerged and this world view is supported by broad societal groups, narratives can provide powerful momentum to trigger innovation and changes in the course of action. Narratives, however, are not necessarily based on evidence and precise categories, but can instead be vague and ambiguous in order to be acceptable and attractive to different actors. However, the more open and inclusive a narrative is, the less impact can be expected. We investigate whether there is a shared narrative in research for the sustainable economy and how this can be evaluated in terms of its potential societal impact. The paper carves out the visions for the future that have been underlying the research projects conducted within the German Federal Ministry of Education and Research (BMBF) funding programme âThe Sustainable Economyâ. It then analyzes whether these visions are compatible with narratives dominating societal discourse on the sustainable economy, and concludes how the use of visions and narratives in research can contribute to fostering societal transformations
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