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Versión en inglés disponible en la Biblioteca Digital del IDRC: Moving Asia from grassroots to cyberspaceVersión en francés disponible en la Biblioteca Digital del IDRC: Asie à l'assaut de l'espace cybernétiqu

Manipulation of fullerene C60 spintronic devices via ferromagnetic resonance

C60 has been included in hybrid magneto-molecular devices as an active layer where the C60 is thermally sublimated under high vacuum and the metals are sputter deposited in-situ. Multilayer C60/Co samples were measured by x-ray reflectivity and transmission electron microscopy to show that there is little interdiffusion of layers suggesting C60 is robust to the deposition of metals by sputtering. We have observed 25% magnetoresistance through 60 nm of C60 at 10 K as well as 8% magnetoresistance at room temperature through 20 nm of C60. Unexpected asymmetric effects in external magnetic field were observed in some C60 spin valves as a result of interfacial hybridisation between C60 and ferromagnetic materials. It has also been shown that when C60 is in contact with a ferromagnetic material, spin polarised electrons from the ferromagnet are transferred into the C60 as a result of differences in chemical potential. This has been measured in C60/Co and C60/Py bilayer samples and observed via ferromagnetic resonance and point contact Andreev reflection. The molecular properties of C60 can be manipulated by an adjacent ferromagnetic material at ferromagnetic resonance dissipating energy into the C60. This changes the frequency/energy of molecular vibrations, as well as an enhanced photoemission from the C60. The changes can be correlated to spin pumping and phonon injection. The conductivity through a C60 layer is also increased during ferromagnetic resonance of the adjacent Py by up to 8% owing to increased phonon-assisted hopping steps

Hot water usage profiling to improve geyser efficiency

This paper presents an intelligent hot water cylinder (HWC) (referred to as geyser) usage profiling system to provide peak demand side management and improve HWC efficiency in a typical household. The study highlights current control topologies used to improve geyser efficiency, as well as the design of the final geyser controller. The system consists of a PIC microcontroller used to determine individually based hot water usage profiles of the user. The controller then regulates the temperature of the geyser according to the demand profile developed. From the results it is apparent that by controlling the geyser temperature and thereby heat loss, savings can be made

Uncoupling protein-2 increases nitric oxide production and TNFAIP3 pathway activation in pancreatic islets

Mutations in the uncoupling protein 2 (Ucp2) gene are linked to type-2 diabetes. Here, a potential mechanism by which lack of UCP2 is cytoprotective in pancreatic β-cells was investigated. Nitric oxide (NO) production was elevated in Ucp2−/− islets. Proliferation (cyclin D2, Ccnd2) and anti-apoptosis (Tnfaip3) genes had increased expression in Ucp2−/− islets, whereas the mRNA of pro-apoptosis genes (Jun, Myc) was reduced. TNFAIP3 cellular localization was detected in both α- and β-cells of Ucp2−/− islets but in neither α- nor β-cells of UCP2+/+ islets, where it was detected in pancreatic polypeptide-expressing cells. TNFAIP3 distribution was not markedly altered 14 days after streptozotocin treatment. Basal apoptosis was attenuated in Ucp2−/− β-cells, while the nuclear factor κB (NF-κB) pathway was transactivated after islet isolation. Ucp2+/+ and Ucp2−/− islets were treated with cytokines for 24 h. Cytokines did not increase NF-κB transactivation or apoptosis in Ucp2−/− islets and TNFAIP3 was more strongly induced in Ucp2−/− islets. Inhibition of NO production strongly reduced NF-κB activation and apoptosis. These data show that null expression of Ucp2 induces transactivation of NF-κB in isolated islets, possibly due to NO-dependent up-regulation of inhibitor of κB kinase β activity. NF-κB transactivation appears to result in altered expression of genes that enhance a pro-survival phenotype basally and when β-cells are exposed to cytokines. TNFAIP3 is of particular interest because of its ability to regulate NF-κB signaling pathways

Narcisse: a mirror view of conserved syntenies

New methods and tools are needed to exploit the unprecedented source of information made available by the completed and ongoing whole genome sequencing projects. The Narcisse database is dedicated to the study of genome conservation, from sequence similarities to conserved chromosomal segments or conserved syntenies, for a large number of animals, plants and bacterial completely sequenced genomes. The query interface, a comparative genome browser, enables to navigate between genome dotplots, comparative maps and sequence alignments. The Narcisse database can be accessed at http://narcisse.toulouse.inra.fr

Multi‑week prediction of livestock chill conditions associated with the northwest Queensland floods of February 2019

The compound extreme weather event that impacted northern Queensland in February 2019 featured record-breaking rainfall, persistent high wind gusts and relatively cold day-time temperatures. This caused livestock losses numbering around 500,000 in the northwest Queensland Gulf region. In this study, we examine the livestock chill conditions associated with this week-long compound weather event and its potential for prediction from eleven world-leading sub-seasonal to seasonal (S2S) forecast systems. The livestock chill index combines daily rainfall, wind and surface temperature data. Averaged over the event week, the potential heat loss of livestock was in the moderate to high category, with severe conditions on the day of peak rainfall (5 February). Using calibrated forecasts from the Bureau of Meteorology's S2S forecast system, ACCESS-S1, a 1-week lead prediction showed a 20–30% probability of extreme livestock chill conditions over the northwest Queensland Gulf region, however the highest probabilities were located to the west of where the greatest livestock impacts were observed. Of the remaining ten S2S systems, around half predicted a more than 20% chance of extreme conditions, more than twice the climatological probability. It appears that the prediction accuracy arose from the skilful forecasts of extreme rainfall, as opposed to cold day-time temperature and strong wind forecasts. Despite a clear association between the observed extreme weather conditions and an active Madden–Julian Oscillation (MJO) event stalling in the western Pacific, the majority of 1-week lead S2S forecasts showed little indication of a slow-down in the MJO. As the livestock chill index was developed for southern Australian sheep, it may not be the best metric to represent the effects of exposure on tropical cattle breeds. Hence, this study draws attention to the need for tailored diagnostics that better represent the cold effects of summer tropical cyclones and tropical depressions on northern Australian livestock

Direct numerical simulation of a tip-leakage flow in a planar duct with a longitudinal slit

A planar duct flow configuration with a cross-flow injected from a longitudinal slit close to the upper wall of the duct is studied by using a direct numerical simulation approach to explore the underlying flow mechanism in relation to the tip-leakage vortex (TLV), which is one of the most important flow phenomena in turbomachinery. Major characteristics of TLV in a rotor of turbomachinery are identified in the current flow model. The analysis of mean and instantaneous flow fields reveals that the interaction between the main (axial) flow and jet (cross) flow is the primary source of the generation of the TLV. The evolution of the TLV is then investigated, and a vortex breakup phenomenon is identified. The evolution of TLV can be divided into three phases, i.e. the formation phase, the break-up phase, and the diffusion phase. Mean streamlines and turbulence kinetic energy (TKE) budgets are analysed, showing that the high TKE central spot in the formation phase is due to the interaction between highly swirling vortex filaments and mean velocity gradient. In the outer part of the TLV, the TKE is mainly produced in the shear-layer and transported towards the centre by the turbulence transport

A Large Sample Study of Red Giants in the Globular Cluster Omega Centauri (NGC 5139)

We present abundances of several light, alpha, Fe-peak, and neutron-capture elements for 66 red giant branch (RGB) stars in the Galactic globular cluster Omega Centauri. Our observations lie in the range 12.0<V<13.5 and focus on the intermediate and metal-rich RGBs. We find that there are at least four peaks in the metallicity distribution function at [Fe/H]=-1.75, -1.45, -1.05, and -0.75, which correspond to about 55%, 30%, 10%, and 5% of our sample, respectively. Additionally, the most metal-rich stars are the most centrally located. Na and Al are correlated despite exhibiting star-to-star dispersions of more than a factor of 10, but the distribution of those elements appears to be metallicity dependent and are divided at [Fe/H]~-1.2. About 40-50% of stars with [Fe/H]<-1.2 have Na and Al abundances consistent with production solely in Type II supernovae and match observations of disk and halo stars at comparable metallicity. The remaining metal-poor stars are enhanced in Na and Al compared to their disk and halo counterparts and are mostly consistent with predicted yields from >5 M_sun asymptotic giant branch (AGB) stars. At [Fe/H]>-1.2, more than 75% of the stars are Na/Al enhanced and may have formed almost exclusively from AGB ejecta. Most of these stars are enhanced in Na by at least 0.2 dex for a given Al abundance than would be expected based on "normal" globular cluster values. All stars in our sample are alpha-rich and have solar-scaled Fe-peak abundances. Eu does not vary extensively as a function of metallicity; however, [La/Fe] varies from about -0.4 to +2 and stars with [Fe/H]>-1.5 have [La/Eu] values indicating domination by the s-process. A quarter of our sample have [La/Eu]>+1 and may be the result of mass transfer in a binary system.Comment: ApJ Accepted; 90 pages, 16 Figures, 5 Table

Connected clusters: landscaping study

This study presents evidence from five dynamic, city region-based climate innovation clusters. Here businesses, academics, communities and government work together to deliver low-carbon innovation. We believe this concentration of resources, expertise and initiative is our best chance of meeting the Paris climate targets while also reaping social and economic benefits that come with the development and delivery of cleantech solutions. Climate-KIC’s ConnectedClusters project is an alliance of five city regions – Birmingham, Edinburgh, Frankfurt, London and Valencia – committed to sharing, replicating and scaling what works in developing innovation ecosystems for delivering effective climate action. Between now and 2020, the project will work hard to accelerate and enable transformation of the places we live into clean, prosperous and thriving cities and regions by developing new collaborative approaches to technology, procurement, investment and training. ConnectedClusters will help inform a transition away from product and technology innovation in isolation, towards a systemic, regionally-embedded approach to climate innovation. Paris shows that for our continued prosperity, transformation on a scale never witnessed before is imperative. Only by working together can we achieve that change

Research priorities for mitochondrial disorders: Current landscape and patient and professional views

Primary mitochondrial disorders encompass a wide range of clinical presentations and a spectrum of severity. They currently lack effective disease-modifying therapies and have a high mortality and morbidity rate. It is therefore essential to know that competitively-funded research designed by academics meets core needs of people with mitochondrial disorders and their clinicians. The Priority Setting Partnerships are an established collaborative methodology that brings patients, carers and families, charity representatives and clinicians together to try to establish the most pressing and unanswered research priorities for a particular disease. We developed a web-based questionnaire, requesting all patients affected by primary mitochondrial disease, their carers, and clinicians to pose their research questions. This yielded 709 questions from 147 participants. These were grouped into overarching themes including basic biology, causation, health services, clinical management, social impacts, prognosis, prevention, symptoms, treatment, and psychological impact. Following the removal of 'answered questions' the process resulted in a list of 42 discrete, answerable questions. This was further refined by web-based ranking by the community to 24 questions. These were debated at a face-to-face workshop attended by a diverse range of patients, carers, charity representatives and clinicians to create a definitive 'Top Ten of unanswered research questions for primary mitochondrial disorders'. These Top Ten questions related to understanding biological processes, including triggers of disease onset, mechanisms underlying progression and reasons for differential symptoms between individuals with identical genetic mutations; new treatments; biomarker discovery; psychological support; and optimal management of stroke-like episodes and fatigue