Four Brown Dwarfs in the Taurus Star-Forming Region

We have identified four brown dwarfs in the Taurus star-forming region. They were first selected from $R$ and $I$ CCD photometry of 2.29 square degrees obtained at the Canada-France-Hawaii Telescope. Subsequently, they were recovered in the 2MASS second incremental data release point source catalog. Low-resolution optical spectra obtained at the William Herschel telescope allow us to derive spectral types in the range M7--M9. One of the brown dwarfs has very strong H$\alpha$ emission (EW=-340 \AA). It also displays Br$\gamma$ emission in an infrared spectrum obtained with IRCS on the Subaru telescope, suggesting that it is accreting matter from a disk. The \ion{K}{1} resonance doublet and the \ion{Na}{1} subordinate doublet at 818.3 and 819.5 nm in these Taurus objects are weaker than in field dwarfs of similar spectral type, consistent with low surface gravities as expected for young brown dwarfs. Two of the objects are cooler and fainter than GG Tau Bb, the lowest mass known member of the Taurus association. We estimate masses of only 0.03 M$_\odot$ for them. The spatial distribution of brown dwarfs in Taurus hints to a possible anticorrelation between the density of stars and the density of brown dwarfs.Comment: ApJ Letters (in press

New infrared star clusters in the Northern and Equatorial Milky Way with 2MASS

We carried out a survey of infrared star clusters and stellar groups on the 2MASS J, H and K_s all-sky release Atlas in the Northern and Equatorial Milky Way (350 < l < 360, 0 < l < 230). The search in this zone complements that in the Southern Milky Way (Dutra et al. 2003a). The method concentrates efforts on the directions of known optical and radio nebulae. The present study provides 167 new infrared clusters, stellar groups and candidates. Combining the two studies for the whole Milky Way, 346 infrared clusters, stellar groups and candidates were discovered, whereas 315 objects were previously known. They constitute an important new sample for future detailed studies.Comment: Accepted to Astronomy and Astrophysic

Warm dusty discs: Exploring the A star 24um debris population

(Abridged) Studies of debris discs have shown that most systems are analogous to the EKB. In this study we aim to determine how many IRAS 25um excesses towards A stars are real, and investigate where the dust lies. We observe with TIMMI2, VISIR, Michelle and TReCS a sample of A and B-type main sequence stars reported as having mid-IR excess. We constrain the location of the debris through combined modelling of the emission spectrum and a modelling technique designed to constrain the radial extent of emission in mid-IR imaging. We independently confirm the presence of warm dust around 3 of the candidates: HD3003, HD80950 and eta Tel. For the binary HD3003 a stability analysis indicates the dust is either circumstellar and lying at ~4 AU with the binary orbiting at >14AU, or the dust lies in an unstable location; there is some evidence for temporal evolution of its excess emission on a ~20 year timescale. For 7 of the targets we present quantitative limits on the location of dust around the star. We demonstrate that the disc around HD71155 must have spatially distinct components at 2 and 60AU. We model the limits of current instrumentation and show that most of the known A star debris discs which could be readily resolved at 18um on 8m instruments have been resolved. Limits from unresolved imaging can help distinguish between competing models of the disc emission, but resolved imaging is key to the determination of the disc location. Modelling of the detection limits for extended emission can be useful for targeting future observational campaigns. MIRI on the JWST will be able to resolve most of the known A star debris disc population. METIS on the E-ELT will provide the opportunity to explore the hot disc population more thoroughly by detecting extended emission where calibration accuracy limits disc detection through photometry, reaching levels below 1 zodi for stars at <10pc.Comment: Accepted for publication in Astronomy and Astrophysic

Framtidsutsikter för pastoralism på Kenyanska betesmarker

Pastoralism är ett system där majoriteten av en individs inkomst och mat kommer från boskapsdjur. Boskapsdjurens huvudsakliga matkälla är naturligt växande bete. Pastoralism kan delas in i tre huvudtyper; nomadisk, transhuman och stillasittande. I Kenya finns variationer av alla tre. Vanliga arter som används inom pastoralistiska system är nötkreatur, getter, får och kameler. Nöttamboskap har traditionellt haft en väldigt central roll inom dessa samhällen och de används bland annat som matkälla, inkomstkälla och hemgift. De är också en statussymbol. Hot mot denna traditionella livsstil kommer bland annat från krympande betesytor, minskade resurser, klimatförändringar och klimatvariationer samt en mänsklig populationsökning som sätter press på landets livsmedelsförsörjning. Syftet med denna studie var att undersöka om nöttamboskap kommer kunna användas på samma sätt och i samma utsträckning i framtiden, finns det alternativa betesmetoder men ändå inom ramen för pastoralism, kan avel på nötkreatur spela en avgörande roll och vilken roll andra arter kan ha. Största hoten kommer från klimatförändringar och landfragmentering. Klimatförändringar kommer troligtvis leda till ökad temperatur, ökad total nederbörd och våtare klimat i Kenya. Ökad temperatur kan påverka vattentillgängligheten och på så sätt förvärra situationer med vattenbrist. Total nederbörd kommer troligtvis att öka och klimatet kommer antagligen bli våtare men olika regioner kommer att påverkas olika. Det kan leda till viss ökning i produktionen av grödor i torra och semitorra områden men den ökade temperaturen leder till ökad avdunstning vilken kan balansera ut den ökade nederbörden. Det stora hotet med klimatförändringar kommer från naturkatastrofer som torka och översvämningar som troligtvis kommer inträffa mer frekvent. Torka och översvämningar kan ha förödande konsekvenser för en pastoralist då de kan leda till ökad mortalitet, sämre reproduktion, förstörelse av betesmarker och ökad incidens av sjukdomar etc. Landfragmentering är isoleringen av landytor och habitat och det orsakas av många faktorer exempelvis privatisering av mark. Landfragmentering begränsar pastoralisters tillgång på betesmarken som i sin tur kan leda till överbetning och jordförstöring. Metoder för att möta dessa hot inkluderar mobila bomas, avel på nötkreatur och att skifta till andra arter. Mobila bomas används för att öka tiden nöttamboskapet spenderar på betet och minska tiden för att gå till betet vilket kan leda till en ökad produktion och minska trycket av mindre betesytor men det är ofta en kostsam investering. Avel på nöttamboskap bör fokuseras på inhemska raser då de troligtvis kommer vara bäst lämpade för det framtida klimatet. På kort sikt kommer avel troligtvis inte ha en större roll men det kan vara viktigt på lång sikt. En av de mer effektiva metoderna för att möta hoten är att förlita sig mer på andra arter än nötkreatur. Framförallt getter och kameler verkar bäst lämpade i framtiden.Pastoralism is a system in which most of an individual’s income and food comes from livestock. The livestock´s primary source of food comes from naturally grown pasture. Pastoralism can be divided into three main types; nomadic, transhumance and sedentary. In Kenya there are variations of all. Species that are commonly used in these systems are cattle, goats, sheep and camels. Traditionally cattle have played a central role within these systems, for instance as a source of food, income and dowry. They are also a symbol of prestige. Threats towards this lifestyle comes in the form of shrinking pastures, shrinking resources, climate change and climate variability, human population growth that puts pressure on the country´s food supply etc. The aim of this study was to investigate, the possibility of using cattle in the same manner and to the same extent in the future, alternative grazing methods that are still within the framework of pastoralism, the role of cattle breeding and what role other species can have. The largest threats are climate change and land fragmentation. Climate change will probably lead to an increase in temperature, increase in total precipitation and a wetter climate in Kenya. Increases in temperature can affect water availability and in turn exacerbate situations of water shortages. Total precipitation will likely increase, and the climate is likely to become wetter but different regions will be affected differently. It could result in an increased production of crops in arid and semi-arid regions, however the increase in temperature will lead to an increase in evaporation which could balance out the increased precipitation. The great threat comes from natural disasters like drought and floods that are likely to become more frequent occurrences. Drought and floods can have devastating consequences for a pastoralist because they can result in increased mortality, worse reproduction, destruction of pastures and increased incidence of diseases etc. Land fragmentation is the isolation of land areas and habitats, and it is caused by many factors for example privatization of land. Land fragmentation limits a pastoralists access to pastures which in turn can lead to overgrazing and land degradation. Methods to face these threats include mobile bomas, breeding on cattle and shifting towards other species. Mobile bomas are used to increase the time cattle spends on pastures and reduces walking time which can lead to an increase in production and can ease the pressure of shrinking pastures. However, it is a costly investment. Breeding on cattle should focus on indigenous breed because they are likely better suited for the future climate. Breeding will likely not have a short-term effect but can play a crucial long-term role. Shifting from cattle to other species is one of the most effective methods to face the threats. Especially goats and camels seem best suited for the future

Increasing cardiac pyruvate dehydrogenase flux during chronic hypoxia improves acute hypoxic tolerance

The pattern of metabolic reprogramming in chronic hypoxia shares similarities with that following myocardial infarction or hypertrophy, however the response of the chronically hypoxic heart to subsequent acute injury, and the role of metabolism is not well understood. Here, we determined the myocardial tolerance of the chronically hypoxic heart to subsequent acute injury, and hypothesised that activation of a key regulator of myocardial metabolism, the pyruvate dehydrogenase complex (PDC), could improve hypoxic tolerance. Mouse hearts, perfused in Langendorff mode, were exposed to 30min of hypoxia, and lost 80% of prehypoxic function (p=0.001), with only 27% recovery of pre-hypoxic function with 30min of re-oxygenation (p=0.046). Activation of the PDC with infusion of 1mM dicholorocacetate (DCA) during hypoxia and re-oxygenation did not alter function. Acute hypoxic tolerance was assessed in hearts of mice housed in hypoxia for 3wks. Chronic hypoxia reduced cardiac tolerance to subsequent acute hypoxia, with recovery of function 22% of pre-acute hypoxic levels, vs 39% in normoxic control hearts (p=0.012). DCA feeding in chronic hypoxia (per os, 70mg/kg/day) doubled cardiac acetylcarnitine content, and this fell following acute hypoxia. This acetylcarnitine use maintained cardiac ATP and glycogen content during acute hypoxia, with hypoxic tolerance normalised. In summary, chronic hypoxia renders the heart more susceptible to acute hypoxic injury, which can be improved by activation of the PDC and pooling of acetylcarnitine. This is the first study showing functional improvement of the chronically hypoxic heart with activation of the PDC, and offers therapeutic potential in cardiac disease with a hypoxic component

Sense of coherence: definition and explanation

The present study is one of a few that have used "sense of coherence" (SOC) as a dependent variable in an explanatory model. After studying three different samples - 680 students, 180 parents and 315 couples - we conclude that family relational and psychopathological variables contribute significantly to the explanation of SOC (explained variance between 10-27 and 26-50 per cent). In total, we obtained an explained variance of between 42 and 64 per cent. This leads us to the conclusion that in all three samples, SOC is multifaceted and thereby is more than simply an opposite state to depression. Context may play an important part in the explanation of SOC

Efficacy and predictors of recovery of function after eye movement training in 296 hemianopic patients

Funding Development of NeuroEyeCoachTM and completion of regulatory requirements were funded by NovaVision Inc and developed by Arash Sahraie and Josef Zihl with the help of a technical team (Insiso Ltd.). Acknowledgements We would like to acknowledge the help of Insiso Ltd., UK for software support and data download. AMHC is supported by a Biotechnology and Biological Sciences Research Council (BBSRC) [grant number BB/J01446X/1] Case Ph.D. Studentship awarded by East of Scotland Bioscience (EastBio) Doctoral Training Partnership in collaboration with NovaVision.Peer reviewedPublisher PD

Phasic alertness and multisensory integration contribute to visual awareness of weak visual targets in audio-visual stimulation under Continuous Flash Suppression

This work was supported by the Biotechnology and Biological Sciences Research Council(BBSRC) [grant number BB/M010996/1].Peer reviewedPublisher PD

Sociala medier som det digitala vardagsrummet

Allt fler företag använder internet och sociala medier för att kommunicera med konsumenter, genom dessa medier har de möjlighet att sprida information om sig själva samt direkt få feedback från allmänheten. Det här har påverkat företags sätt att utbyta information med konsumenter och medför därför nya risker och möjligheter för företag att beakta. Studien undersöker hur företag använder och förvaltar sin vardagliga närvaro i sociala medier. Ett ramverk har utformats baserat på den teori som presenteras och har legat som grund för den empiriska analysen. Ramverket består av fem kategorier; bakgrund i sociala medier, syfte med sociala medier, strategi för sociala medier, risk- och krishantering i sociala medier samt kommunikation i sociala medier. Undersökningen har genomförts genom att semistrukturerade intervjuer har gjorts på fem stycken företag om hur deras arbete i sociala medier ser ut. Det teoretiska ramverket har används för att analysera intervjuerna grundligt och få fram resultatet. Huvudresultatet visar på att det hos de undersökta företagen finns en god medvetenhet för hur de sköter det vardagliga arbetet i sociala medier. Studien visar även på att en viktig möjlighet för företagen med att vara aktiva i sociala medier är att kunna ta del av kunders åsikter