Snap evaporation of droplets on smooth topographies

Droplet evaporation on solid surfaces is important in many applications including printing, micro-patterning and cooling. While seemingly simple, the configuration of evaporating droplets on solids is difficult to predict and control. This is because evaporation typically proceeds as a “stick-slip” sequence—a combination of pinning and de-pinning events dominated by static friction or “pinning”, caused by microscopic surface roughness. Here we show how smooth, pinning-free, solid surfaces of non-planar topography promote a different process called snap evaporation. During snap evaporation a droplet follows a reproducible sequence of configurations, consisting of a quasi-static phase-change controlled by mass diffusion interrupted by out-of-equilibrium snaps. Snaps are triggered by bifurcations of the equilibrium droplet shape mediated by the underlying non-planar solid. Because the evolution of droplets during snap evaporation is controlled by a smooth topography, and not by surface roughness, our ideas can inspire programmable surfaces that manage liquids in heat- and mass-transfer applications

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

Search for direct stau production in events with two hadronic tau-leptons in root s=13 TeV pp collisions with the ATLAS detector

A search for the direct production of the supersymmetric partners ofτ-leptons (staus) in final stateswith two hadronically decayingτ-leptons is presented. The analysis uses a dataset of pp collisions corresponding to an integrated luminosity of139fb−1, recorded with the ATLAS detector at the LargeHadron Collider at a center-of-mass energy of 13 TeV. No significant deviation from the expected StandardModel background is observed. Limits are derived in scenarios of direct production of stau pairs with eachstau decaying into the stable lightest neutralino and oneτ-lepton in simplified models where the two staumass eigenstates are degenerate. Stau masses from 120 GeV to 390 GeV are excluded at 95% confidencelevel for a massless lightest neutralino

Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

On the relation between weather variables and sorghum ergot infection

Sorghum ergot (Claviceps africana) has had a significant impact on seed production and breeders’ nurseries in Australia since it was first found in 1996. In this paper, 3 distinct key development stages of sorghum that are related to ergot infection were identified: flag leaf stage, pollen starch accumulation stage, and flowering period. Relationships between weather variables during these 3 stages and ergot severity as well as pollen viability were analysed using observed data from 2 field trials, a serial planting trial and a genotype trial, conducted at Gatton, Queensland. The duration of the flag leaf stage and of the flowering period was estimated from thermal time. An infection factor was introduced and calculated based on hourly temperature during the flowering period. This infection factor and the mean relative humidity at 0900 hours during the flowering period were the main factors influencing ergot infection. Mean daily minimum temperature during flag leaf stage also had a significant effect on ergot severity, although no significant relation was found between this mean daily minimum temperature and pollen viability. A linear regression model using the above 3 factors accounted for 94% of the environmentally caused variation in ergot severity observed in the genotype trial

17th Biennial Australasian Plant Pathology Society Conference (APPS 2009): Plant Health Management: An Integrated Approach

Crown rot of wheat, caused by Fusarium pseudograminearum (Fp), is a serious disease threat across the Australian wheat belt. Currently control of this disease relies on farming practices (e.g. crop rotation) and planting of less susceptible cultivars. Partial resistance has been identified in a small number of wheat lines, such as 2–49 and Sunco, but the mechanisms of resistance shown by these lines have not been identified

4th Asian Conference on Plant Pathology and the 18th Biennial Australasian Plant Pathology Society Conference (ACPP/APPS 2011): New Frontiers in Plant Pathology for Asia and Oceania

Crown rot of wheat is a significant cause of yield losses in many wheat producing countries, particularly Australia where the predominant cause is the fungus Fusarium pseudograminearum. Other cereals such as durum wheat and barley can also be affected. Partial resistance has been identified in a small number of wheat lines, such as 2-49 and Sunco, but the mechanisms of resistance shown by these lines have not been identified. Using quantitative PCR based on fungal translation elongation factor α DNA we have established that fungal biomass in partially resistant genotypes is reduced compared to susceptible genotypes in both seedling and adult cereal tissues. Histopathological examination of infection and colonisation of seedling and adult tissues, using the fluorescent dye solophenyl flavine, has not revealed any differences in tissue responses between partially resistant and susceptible host tissues, although there is a significantly slower spread of the fungus in the tissues of resistant genotypes. Infection is initiated predominantly through the stomata of surface-inoculated leaf sheaths. Colonisation of expanded stems frequently originates in the parenchymatous hypoderm, which becomes highly discoloured. Early infection of pith parenchyma cells is also frequent. Vascular tissues become colonised by anthesis and this occurs more rapidly in susceptible genotypes. Occlusion of large xylem vessels was rare during moderate infections while infection of phloem sieve tube elements is common

17th Biennial Australasian Plant Pathology Society Conference (APPS 2009): Plant Health Management: An Integrated Approach

Crown rot of winter cereals is a major constraint on grain production across most growing regions in Australia, particularly where stubble retention is practiced to maintain soil structure and retain soil water. The predominant cause of this disease is infection with Fusarium pseudograminearum (Fpg), although in some southern areas Fusarium culmorum infections are also significant. These Fusarium species are able to grow saprophytically on stubble remnants over the summer and provide inoculum for crop infection in the following season. Losses due to crown rot are highest in seasons featuring a dry finish in which maturing plants experience water stress, with symptoms including basal stem browning and white heads bearing no grain

11th International Wheat Genetics Symposium 2008 (IWGS 2008)

Crown rot of wheat is a significant cause of yield losses in many wheat producing countries. In Australia crown rot is predominantly caused by the fungus Fusarium pseudograminearum (teleomorph Gibberella coronicola). Partial resistance has been identified in a small number of wheat lines, such as 2-49 and Sunco, but the mechanisms of resistance shown by these lines have not been identified. This study aims to identify key growth periods of F. pseudograminearum during crown rot development in wheat and compare these periods across partially resistant and susceptible lines in order to determine how the disease progresses and when resistance mechanisms are induced