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Eccentric Taylor-Couette Flow with orbital motion of the inner cylinder
This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.The flow in a Taylor-Couette system is one of the most explored flows today. The behaviour of the flow is characterized by Reynolds number, radii and aspect ratio. By reducing the gap width the Taylor-Couette system can be used as a simplified bearing model which has one additional feature. To cover flow effects of a real bearing the rotating inner cylinder moves on an offset track. Thus the system is also characterized by a varying annulus. That changes the eccentricity which is also related to the critical Reynolds number for the system. There is a higher Reynolds number for a higher eccentricity. This is used as a benchmark to validate the code. Depending on the eccentric position of the rotating inner cylinder one can notice either Taylor Vortex flow or Couette Flow. After testing the code the gap width will be adjusted to realistic bearing geometries. This second part refers to bearing simulations where the gap width is adjusted to real bearing conditions. In Fact the present system is a simplified bearing, which covers not all details of a real one. It becomes more complex in later stages of the project, where oil feedings and notches are implemented as well as the occurrence of cavitation. Furthermore the offset tracks will be much more complex. The final goal is to develop a 3D simulation tool for hydrodynamic journal bearings that resolves effects like cross flow from the oil feedings and also cavitation. Known methods based on the Reynolds equations fail to predict important flow characteristics in complex bearing geometries due to their two dimensional nature. If sufficiently low local pressure areas occur, cavitation- related damages may appear. So the pressure distribution of the flow is of interest
Timing of progression from Chlamydia trachomatis infection to pelvic inflammatory disease: a mathematical modelling study
PMCID: PMC3505463The electronic version of this article is the complete one and can be found online at: http://www.biomedcentral.com/1471-2334/12/187.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Herzog & Rowan, ISAZ 2019 Meeting Presentation
The presentation covers differences in relative pet dog (dogs per 1,000 people) and cat populations in different states in the United States and in different countries around the world
Non-local two-photon correlations using interferometers physically separated by 35 meters
An experimental demonstration of quantum correlations is presented. Energy
and time entangled photons at wavelengths of 704 and 1310 nm are produced by
parametric downconversion in KNbO3 and are sent through optical fibers into a
bulk-optical (704 nm) and an all-fiber Michelson-interferometer (1310 nm),
respectively. The two interferometers are located 35 meters aside from one
another. Using Faraday-mirrors in the fiber-interferometer, all birefringence
effects in the fibers are automatically compensated. We obtained two-photon
fringe visibilities of up to 95 % from which one can project a violation of
Bell's inequality by 8 standard deviations. The good performance and the
auto-aligning feature of Faraday-mirror interferometers show their potential
for a future test of Bell's inequalities in order to examine
quantum-correlations over long distances.Comment: 9 pages including 3 postscript figures, to be published in Europhys.
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Critical dynamics in spontaneous resting-state oscillations are associated with the attention-related P300 ERP in a go/nogo task
Sustained attention is the ability to continually concentrate on task-relevant information, even in the presence of distraction. Understanding the neural mechanisms underlying this ability is critical for comprehending attentional processes as well as neuropsychiatric disorders characterized by attentional deficits, such as attention deficit hyperactivity disorder (ADHD). In this study, we aimed to investigate how trait-like critical oscillations during rest relate to the P300 evoked potential-a biomarker commonly used to assess attentional deficits. We measured long-range temporal correlations (LRTC) in resting-state EEG oscillations as index for criticality of the signal. In addition, the attentional performance of the subjects was assessed as reaction time variability (RTV) in a continuous performance task following an oddball paradigm. P300 amplitude and latencies were obtained from EEG recordings during this task. We found that, after controlling for individual variability in task performance, LRTC were positively associated with P300 amplitudes but not latencies. In line with previous findings, good performance in the sustained attention task was related to higher P300 amplitudes and earlier peak latencies. Unexpectedly, we observed a positive relationship between LRTC in ongoing oscillations during rest and RTV, indicating that greater criticality in brain oscillations during rest relates to worse task performance. In summary, our results show that resting-state neuronal activity, which operates near a critical state, relates to the generation of higher P300 amplitudes. Brain dynamics close to criticality potentially foster a computationally advantageous state which promotes the ability to generate higher event-related potential (ERP) amplitudes
Post-transcriptional regulation by 3' UTRs can be masked by regulatory elements in 5' UTRs
In mRNA sequences, 3' UTRs are thought to contain most elements that specifically regulate localization, turnover, and translation. Although high-throughput experiments indicate that many RNA-binding proteins (RBPs) also bind 5' UTRs, much less is known about specific post-transcriptional control exerted by 5' UTRs. GLD-1 is a conserved RBP and a translational repressor with essential roles in Caenorhabditis elegans germ cell development. Previously, we showed that GLD-1 binds highly conserved sites in both 3' and 5' UTRs. Here, by targeted single-copy insertion of transgenes, we systematically tested in vivo functionality of 5' and 3' UTR binding sites individually and in combination. Our data show that sites in 5' UTRs mediate specific and strong translational repression, independent of exact position. Intriguingly, we found that the functionality of 3' UTR sites can be masked by 5' UTR sites and vice versa. We conclude that it is important to study both UTRs simultaneously
Compositional Performance Modelling with the TIPPtool
Stochastic process algebras have been proposed as compositional specification formalisms for performance models. In this paper, we describe a tool which aims at realising all beneficial aspects of compositional performance modelling, the TIPPtool. It incorporates methods for compositional specification as well as solution, based on state-of-the-art techniques, and wrapped in a user-friendly graphical front end. Apart from highlighting the general benefits of the tool, we also discuss some lessons learned during development and application of the TIPPtool. A non-trivial model of a real life communication system serves as a case study to illustrate benefits and limitations
Health Behaviors and Behavior Change during Pregnancy: Theory-Based Investigation of Predictors and Interrelations
(1) Background: Preventing pregnancy complications and maternal deaths and helping women stay healthy before, during, and after pregnancy by means of sexual health and behavior is imperative. Previous research demonstrated that a lack of social support and perceived discrimination have adverse effects on pregnancy outcomes. These determinants may impact health behavior as an important mediator of pregnancy outcomes. To better understand this relation, the Compensatory Carry-Over Action Model (CCAM) was applied. The research question was: how do predictors of health behavior, specifically intention, planning, self-efficacy, social support, and discrimination, interrelate with different health behaviors during pregnancy? (2) Methods: By means of qualitative interviews with ten pregnant women (20â39 years, mean = 28.6) from different cultural backgrounds, the predictors of health behaviors and experiences with pregnancy, including racial discrimination, were investigated. (3) Results: Not all women changed their unhealthy behaviors even though their higher-level goal was to ensure their babyâs and their own health. This appeared partially due to lack of social support, racial discrimination, and unexpected pregnancy side effects. The women who previously performed health behaviors revealed a healthier pattern with maintaining or even expanding their health behaviors, while those performing no health behavior in the past reported more obstacles with a healthy lifestyle. (4) Conclusions: Pregnant women appear to be having difficulties translating good intentions into behavior. The reasons include lack of support, fear, and insecurity, which impact self-efficacy and planning. Improvements in health behaviors were facilitated by specific circumstances, such as working from home. Policy and practice should take these aspects into account and help mobilize support and overcome discrimination by means of more rights and support for pregnant women while also empowering the individuals
Social Attitudes and Animals
This chapter is an overview of the attitudes of Americans toward the treatment and moral status of nonhuman animals. We discuss problems of attitude assessment, the social psychology of attitudes toward animals, and the complex relationship between attitudes and behavior. We also review changes in attitudes toward animals over the past fifty years and current public opinion regarding a variety of issues related to animal welfare
The large N limit of M2-branes on Lens spaces
We study the matrix model for N M2-branes wrapping a Lens space L(p,1) =
S^3/Z_p. This arises from localization of the partition function of the ABJM
theory, and has some novel features compared with the case of a three-sphere,
including a sum over flat connections and a potential that depends
non-trivially on p. We study the matrix model both numerically and analytically
in the large N limit, finding that a certain family of p flat connections give
an equal dominant contribution. At large N we find the same eigenvalue
distribution for all p, and show that the free energy is simply 1/p times the
free energy on a three-sphere, in agreement with gravity dual expectations.Comment: 28 pages, 4 figure
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