Depinning of three-dimensional drops from wettability defects

Substrate defects crucially influence the onset of sliding drop motion under lateral driving. A finite force is necessary to overcome the pinning influence even of microscale heterogeneities. The depinning dynamics of three-dimensional drops is studied for hydrophilic and hydrophobic wettability defects using a long-wave evolution equation for the film thickness profile. It is found that the nature of the depinning transition explains the experimentally observed stick-slip motion.Comment: 6 pages, 9 figures, submitted to ep

Modelling the evaporation of thin films of colloidal suspensions using Dynamical Density Functional Theory

Recent experiments have shown that various structures may be formed during the evaporative dewetting of thin films of colloidal suspensions. Nano-particle deposits of strongly branched `flower-like', labyrinthine and network structures are observed. They are caused by the different transport processes and the rich phase behaviour of the system. We develop a model for the system, based on a dynamical density functional theory, which reproduces these structures. The model is employed to determine the influences of the solvent evaporation and of the diffusion of the colloidal particles and of the liquid over the surface. Finally, we investigate the conditions needed for `liquid-particle' phase separation to occur and discuss its effect on the self-organised nano-structures

Developing a dataset of real projects for portfolio, program and project control management research

This article introduces a dataset comprising a portfolio of six projects each having a baseline consisting of a budget derived from a standardized first-principles, bottom-up estimation technique. The projects utilize a homogeneous set of resources, both consumable and non-consumable, which are inter-related in a highly complex, multi-dimensional manner with appropriate correlation between quantity, productivity rates and cost rates. The dataset also includes detailed time-phased actual costs and progress over the life of each project as well as the time-phased values of revenue claimed for each project. The collection and attribution of 12,139 actual costs and the measurement of progress over a period of just under 109 consecutive weeks is consistent and standardized across all six projects providing a unique differentiator to other datasets. The data is valid for research in portfolio, program, or project (PPP) management or control of multiple resource-constrained projects, where projects are managed collectively, generally in a standardized manner to support a strategic business aim

Non-invasive genetic approaches for estimation of ungulate population size: a study on roe deer (Capreolus capreolus) based on faeces

Estudios genéticos no invasivos, para la estimación del tamaño de una población de ungulados: estudio sobre el corzo (Capreolus capreolus) basado en sus heces La estimación de los tamaños de población es particularmente difícil en las especies de animales que viven en hábitats de vegetación densa, en la que se pueden mimetizar. Este es el caso del corzo, al igual que el de muchos otros ungulados. Nuestro objetivo fue desarrollar una aproximación genética no invasiva de captura–marcado–recaptura basada en las heces de corzo recogidas a lo largo de transectos. En un estudio piloto, recogimos 1.790 heces de corzo durante cinco días de muestreo en un área de estudio boscosa en el sudoeste de Alemania. Extrajimos el ADN de 410 de dichas muestras y llevamos a cabo un análisis de microsatélites utilizando siete marcadores de dinucleótidos. Los análisis tuvieron como resultado 328 genotipos consenso, que se asignaron a 174 individuos. La población estimada usando el enfoque bayesiano fue de 94 (82–111) machos y 136 (121–156) hembras. Nuestro estudio demuestra que los métodos genéticos no invasivos constituyen una herramienta de gestión muy valiosa para el corzo.Estudios genéticos no invasivos, para la estimación del tamaño de una población de ungulados: estudio sobre el corzo (Capreolus capreolus) basado en sus heces La estimación de los tamaños de población es particularmente difícil en las especies de animales que viven en hábitats de vegetación densa, en la que se pueden mimetizar. Este es el caso del corzo, al igual que el de muchos otros ungulados. Nuestro objetivo fue desarrollar una aproximación genética no invasiva de captura–marcado–recaptura basada en las heces de corzo recogidas a lo largo de transectos. En un estudio piloto, recogimos 1.790 heces de corzo durante cinco días de muestreo en un área de estudio boscosa en el sudoeste de Alemania. Extrajimos el ADN de 410 de dichas muestras y llevamos a cabo un análisis de microsatélites utilizando siete marcadores de dinucleótidos. Los análisis tuvieron como resultado 328 genotipos consenso, que se asignaron a 174 individuos. La población estimada usando el enfoque bayesiano fue de 94 (82–111) machos y 136 (121–156) hembras. Nuestro estudio demuestra que los métodos genéticos no invasivos constituyen una herramienta de gestión muy valiosa para el corzo.Estimating population size is particularly difficult for animal species living in concealing habitats with dense vegetation. This is the case for roe deer as for many other ungulates. Our objective was to develop a non–invasive genetic capture–mark–recapture approach based on roe deer faeces collected along transects. In a pilot study, we collected 1,790 roe deer faeces during five sampling days in a forested study area in south western Germany. We extracted DNA from 410 of these samples and carried out microsatellite analysis using seven dinucleotide markers. The analyses resulted in 328 useable consensus genotypes which were assigned to 174 individuals. The population size estimated using a Bayesian approach was 94 (82–111) male and 136 (121–156) female roe deer. Our study shows that non–invasive genetic methods are a valuable management tool for roe deer

The use of preferred social stimuli as rewards for rhesus macaques in behavioural neuroscience

Macaques are often motivated to perform in neuroscientific experiments by implementing fluid restriction protocols. Daily access to water is controlled and the monkeys are rewarded with droplets of fluid for performing correct trials in the laboratory. Although these protocols are widely used and highly effective, it is important from a 3Rs perspective to investigate refinements that may help to lessen the severity of the fluid restriction applied. We assessed the use of social stimuli (images of conspecifics) as rewards for four rhesus macaques performing simple cognitive tasks. We found that individual preferences for images of male faces, female perinea and control stimuli could be identified in each monkey. However, using preferred images did not translate into effective motivators on a trial-by-trial basis: animals preferred fluid rewards, even when fluid restriction was relaxed. There was no difference in the monkeys’ performance of a task when using greyscale versus colour images. Based on our findings, we cannot recommend the use of social stimuli, in this form, as a refinement to current fluid restriction protocols. We discuss the potential alternatives and possibilities for future research

Damping by slow relaxing rare earth impurities in Ni80Fe20

Doping NiFe by heavy rare earth atoms alters the magnetic relaxation properties of this material drastically. We show that this effect can be well explained by the slow relaxing impurity mechanism. This process is a consequence of the anisotropy of the on site exchange interaction between the 4f magnetic moments and the conduction band. As expected from this model the magnitude of the damping effect scales with the anisotropy of the exchange interaction and increases by an order of magnitude at low temperatures. In addition our measurements allow us to determine the relaxation time of the 4f electrons as a function of temperature

A lattice of microtraps for ultracold atoms based on patterned magnetic films

We have realized a two dimensional permanent magnetic lattice of Ioffe-Pritchard microtraps for ultracold atoms. The lattice is formed by a single 300 nm magnetized layer of FePt, patterned using optical lithography. Our magnetic lattice consists of more than 15000 tightly confining microtraps with a density of 1250 traps/mm$^2$. Simple analytical approximations for the magnetic fields produced by the lattice are used to derive relevant trap parameters. We load ultracold atoms into at least 30 lattice sites at a distance of approximately 10 $\mu$m from the film surface. The present result is an important first step towards quantum information processing with neutral atoms in magnetic lattice potentials.Comment: 7 pages, 7 figure

Frequency Scaling as a Security Threat on Multicore Systems

Most modern processors use Dynamic Voltage and Frequency Scaling (DVFS) for power management. DVFS allows to optimize power consumption by scaling voltage and frequency depending on performance demand. Previous research has indicated that this frequency scaling might pose a security threat in the form of a covert channel, which could leak sensitive information. However, an analysis able to determine whether DVFS is a serious security issue is still missing. In this paper, we conduct a detailed analysis of the threat potential of a DVFS-based covert channel. We investigate two multicore platforms representative of modern laptops and hand-held devices. Furthermore, we develop a channel model to determine an upper bound to the channel capacity, which is in the order of 1 bit per channel use. Last, we perform an experimental analysis using a novel transceiver implementation. The neural network based receiver yields packet error rates between 1% and 8% at average throughputs of up to 1.83 and 1.20 bits per second for platforms representative of laptops and hand-held devices, respectively. Considering the well-known small message criterion, our results show that a relevant covert channel can be established by exploiting the behaviour of computing systems with DVFS.ISSN:0278-0070ISSN:1937-415