578 research outputs found
Interacting mesoscopic capacitor out of equilibrium
We consider the full nonequilibrium response of a mesoscopic capacitor in the large transparency limit, exactly solving a model with electron-electron interactions appropriate for a cavity in the quantum Hall regime. For a cavity coupled to the electron reservoir via an ideal point contact, we show that the response to any time-dependent gate voltage Vg(t) is strictly linear in Vg. We analyze the charge and current response to a sudden gate voltage shift and find that this response is not captured by a simple circuit analogy. In particular, in the limit of strong interactions a sudden change in the gate voltage leads to the emission of a sequence of multiple charge pulses, the width and separation of which are controlled by the charge-relaxation time Ď„c=hCg/e2 and the time of flight Ď„f. We also consider the effect of a finite reflection amplitude in the point contact, which leads to nonlinear-in-gate-voltage corrections to the charge and current response
Intrinsically S1 3-Linked Graphs and Other Aspects of S1 Embeddings
A graph can be embedded in various spaces. This paper examines S1 embeddings of graphs. Just as links can be defined in spatial embeddings of graphs, links can be defined in S1 embeddings. Because linking properties are preserved under vertex expansion, there exists a finite complete set of minor minimal graphs such that every S1 embedding contains a non-split 3-link. This paper presents a list of minor minimal intrinsically S1 3-linked graphs, along with methods used to find and verify the list, in hopes of obtaining the complete minor minimal set. Other aspects of S1 embeddings are also examined.
The citizens’ perspective : awareness, feelings and acceptance of surveillance and surveillance systems for fighting crime in the UK. A quantitative study
This document presents the results for the United Kingdom within the framework of a larger study undertaken as part of the RESPECT project – “Rules, Expectations and Security through Privacy-enhanced Convenient Technologies” (RESPECT; G.A. 285582) – which was co-financed by the European Commission within the Seventh Framework Programme (2007-2013). Analyses are based on a survey regarding the perceptions, feelings, attitudes and behaviours of citizens towards surveillance for the purpose of fighting crime, carried out amongst a quota sample that is representative of the population in the UK for age and gender. Responses were gathered, predominantly, through an online survey supplemented by a number of questionnaires administered in face to face interviews, in order to fulfil the quota and also reach those citizens who do not use the internet. The questionnaire consisted of 50 questions and was available online in all languages of the European Union between November 2013 and March 2014. The face to face interviews were carried out between January and March 2014. The UK sample is based on the responses from 250 individuals who indicated the UK as their country of residence in the online survey or were administered the questionnaire face to face. As a result, the UK respondents indicated a strongly felt lack of trust in the protection of, and control over, personal information gathered via surveillance. Further, the majority of respondents feel more unhappy than happy with the different types of surveillance (except CCTV), and they feel also unhappy about surveillance taking place without them knowing about it. Additionally, there is a link between feeling happy, or unhappy, about surveillance and feeling secure or insecure through the presence of surveillance. UK respondents appear to have two distinct, and very different, reactions to surveillance. Some people feel secure in the presence of surveillance, but in others surveillance produces feelings of insecurity. However, analyses also indicate that increasing the perceived effectiveness of surveillance measures and increasing the perceived effectiveness of laws regarding the protection of personal data gathered via surveillance may make citizens feel more secure. More research is needed to disentangle the relationships and effects between surveillance measures, feelings of security or insecurity, and citizens’ general quality of life feelings.This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 285582.peer-reviewe
Effect of a High Intake of Conjugated Linoleic Acid on Lipoprotein Levels in Healthy Human Subjects
Background -Trans fatty acids are produced either by industrial hydrogenation or by biohydrogenation in the rumens of cows and sheep. Industrial trans fatty acids lower high-density lipoprotein (HDL) cholesterol, raise low-density lipoprotein (LDL) cholesterol, and increase the risk of coronary heart disease. The effects of trans fatty acids from ruminants are less clear. We investigated the effect on blood lipids of cis-9, trans-11 conjugated linoleic acid (CLA), a trans fatty acid largely restricted to ruminant fats. Methodology/Principal Findings - Sixty-one healthy women and men were sequentially fed each of three diets for three weeks, in random order, for a total of nine weeks. Diets were identical except for 7% of energy (approximately 20 g/day), which was provided either by oleic acid, by industrial trans fatty acids, or by a mixture of 80% cis-9, trans-11 and 20% trans-10, cis-12 CLA. After the oleic acid diet, mean (± SD) serum LDL cholesterol was 2.68±0.62 mmol/L compared to 3.00±0.66 mmol/L after industrial trans fatty acids (
Molecular rotors to probe the local viscosity of a polymer glass
We investigate the local viscosity of a polymer glass around its glass
transition temperature using environment-sensitive fluorescent molecular rotors
embedded in the polymer matrix. The rotors' fluorescence depends on the local
viscosity, and measuring the fluorescence intensity and lifetime of the probe
therefore allows to measure the local free volume in the polymer glass when
going through the glass transition. This also allows us to study the local
viscosity and free volume when the polymer film is put under an external
stress. We find that the film does not flow homogeneously, but undergoes shear
banding that is visible as a spatially varying free volume and viscosity.Comment: 8 pages, 7 figure
Project ECHO (Electronically Controlled HOusing)
Treball desenvolupat dins el marc del programa 'European Project Semester'.There are many environmental issues that inflict aquatic life across the planet. Proper monitoring can be essential with preserving aquatic life and preventing any further damage. La Escola Politècnica Superior d'Enginyeria de Vilanova i la Geltrú (EPSEVG) and Laboratory of Applied Bioacoustics (LAB) sponsored a project, called Project ECHO, that would make monitoring aquatic life easier and more efficient. This project’s main goal was improve the deployment of monitoring equipment process LAB already had in place.
The most prevalent issues this project aims to solve is how much energy is wasted during deployment of monitoring equipment and how it is not guaranteed the monitoring equipment is working before deployment. In order to save energy and prevent a faulty deployment, a bidirectional communication system can be established that will receive the operating status of the monitoring equipment and be able to power it on and off.
The approach of this project was to create a remote control to act as a bidirectional communication system. During the discussion of how to implement this system, it was decided that a housing to hold the equipment and power supply should both be researched and designed. The designed housing eases the deployment and retrieval of the system and protects monitoring equipment at the necessary depths. The result is a system that is interacted with wirelessly and can be easily deployed for a minimum period of 6 months
A novel semi auto-segmentation method for accurate dose and NTCP evaluation in adaptive head and neck radiotherapy
Background and purpose: Accurate segmentation of organs-at-risk (OARs) is crucial but tedious and time-consuming in adaptive radiotherapy (ART). The purpose of this work was to automate head and neck OAR-segmentation on repeat CT (rCT) by an optimal combination of human and auto-segmentation for accurate prediction of Normal Tissue Complication Probability (NTCP). Materials and methods: Human segmentation (HS) of 3 observers, deformable image registration (DIR) based contour propagation and deep learning contouring (DLC) were carried out to segment 15 OARs on 15 rCTs. The original treatment plan was re-calculated on rCT to obtain mean dose (D-mean) and con-sequent NTCP-predictions. The average Dmean and NTCP-predictions of the three observers were referred to as the gold standard to calculate the absolute difference of D-mean and NTCP-predictions (vertical bar AD(mean)vertical bar and vertical bar ANTCP vertical bar). Results: The average vertical bar AD(mean)vertical bar of parotid glands in HS was 1.40 Gy, lower than that obtained with DIR and DLC (3.64 Gy, p < 0.001 and 3.72 Gy, p < 0.001, respectively). DLC showed the highest vertical bar AD(mean)vertical bar in middle Pharyngeal Constrictor Muscle (PCM) (5.13 Gy, p = 0.01). DIR showed second highest vertical bar AD(mean)vertical bar in the cricopharyngeal inlet (2.85 Gy, p = 0.01). The semi auto-segmentation (SAS) adopted HS, DIR and DLC for segmentation of parotid glands, PCM and all other OARs, respectively. The 90th percentile vertical bar ANTCP vertical bar was 2.19%, 2.24%, 1.10% and 1.50% for DIR, DLC, HS and SAS respectively. Conclusions: Human segmentation of the parotid glands remains necessary for accurate interpretation of mean dose and NTCP during ART. Proposed semi auto-segmentation allows NTCP-predictions within 1.5% accuracy for 90% of the cases. (C) 2021 The Author(s). Published by Elsevier B.V
Sperm numbers as a paternity guard in a wild bird
Sperm competition is thought to impose strong selection on males to produce competitive ejaculates to outcompete rival males under competitive mating conditions. Our understanding of how different sperm traits influence fertilization success, however, remains limited, especially in wild populations. Recent literature highlights the importance of incorporating multiple ejaculate traits and pre-copulatory sexually selected traits in analyses aimed at understanding how selection acts on sperm traits. However, variation in a male’s ability to gain fertilization success may also depend upon a range of social and ecological factors that determine the opportunity for mating events both within and outside of the social pair-bond. Here, we test for an effect of sperm quantity and sperm size on male reproductive success in the red-back fairy-wren (Malurus melanocephalus) while simultaneously accounting for pre-copulatory sexual selection and potential socio-ecological correlates of male mating success. We found that sperm number (i.e., cloacal protuberance volume), but not sperm morphology, was associated with reproductive success in male red-backed fairy-wrens. Most notably, males with large numbers of sperm available for copulation achieved greater within-pair paternity success. Our results suggest that males use large sperm numbers as a defensive strategy to guard within-pair paternity success in a system where there is a high risk of sperm competition and female control of copulation. Finally, our work highlights the importance of accounting for socio-ecological factors that may influence male mating opportunities when examining the role of sperm traits in determining male reproductive success
Pharmacokinetics and Safety of Micafungin in Infants Supported With Extracorporeal Membrane Oxygenation
Candida is a leading cause of infection in infants on extracorporeal membrane oxygenation (ECMO). Optimal micafungin dosing is unknown in this population because ECMO can alter drug pharmacokinetics (PK)
Traditional and Health-Related Philanthropy: The Role of Resources and Personality
I study the relationships of resources and personality characteristics to charitable giving, postmortem organ donation, and blood donation in a nationwide sample of persons in households in the Netherlands. I find that specific personality characteristics are related to specific types of giving: agreeableness to blood donation, empathic concern to charitable giving, and prosocial value orientation to postmortem organ donation. I find that giving has a consistently stronger relation to human and social capital than to personality. Human capital increases giving; social capital increases giving only when it is approved by others. Effects of prosocial personality characteristics decline at higher levels of these characteristics. Effects of empathic concern, helpfulness, and social value orientations on generosity are mediated by verbal proficiency and church attendance.
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