Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal

Anthropogenic intensification of short-duration rainfall extremes

Short- duration (1-3 h) rainfall extremes can cause serious damage to societies through rapidly developing (flash) flooding and are determined by complex, multifaceted processes that are altering as Earth's climate warms. In this Review, we examine evidence from observational, theoretical and modelling studies for the intensification of these rainfall extremes, the drivers and the impact on flash flooding. Both short- duration and long- duration (\textgreater1 day) rainfall extremes are intensifying with warming at a rate consistent with the increase in atmospheric moisture (~7% K-1), while in some regions, increases in short- duration extreme rainfall intensities are stronger than expected from moisture increases alone. These stronger local increases are related to feedbacks in convective clouds, but their exact role is uncertain because of the very small scales involved. Future extreme rainfall intensification is also modulated by changes to temperature stratification and large- scale atmospheric circulation. The latter remains a major source of uncertainty. Intensification of short- duration extremes has likely increased the incidence of flash flooding at local scales and this can further compound with an increase in storm spatial footprint to considerably increase total event rainfall. These findings call for urgent climate change adaptation measures to manage increasing flood risks

To a ecotope system for the Dutch marine and estuarine waters

In the context of the Policy-oriented ecological research for the North Sea and Wadden Sea (BEON) spearhead study, "Habitat disturbance", it soon became apparent that the questions arising on habitat disturbance could only be approached efficiently when a clear, preferably geographical, classification of the Dutch marine and estuarine waters was available. Such a classification was already available for terrestrial systems and several types of fresh waters, but not for saline waters. For this reason, developing a system to be used for this purpose became the main occupation of the working group on "cartography of habitats/ecotopes in Dutch marine and estuarine waters". Partial studies concentrated on identifying the abiotic factors determining the occurrence of benthos and fish (and showing how the factors work), as well as the species composition of these groups. A short literature study led to the conclusion that the intended classification should be based on ecotopes, rather than habitats. Criteria to distinguish ecotopes were defined using information from the above-mentioned partial studies, but the main consideration was for processes forming and sustaining ecotopes, followed by factors with a specific relevance to flora and fauna. Next, a hierarchical system of ecotope characteristics was designed, leading to a list of ecotopes. An attempt was made to link up with existing classifications for terrestrial and freshwater systems. No classes for the characteristics are reported here, since these can vary per ecotope according to the different water systems under consideration, and even per defined purpose of a given study. The specially devised GIS application HABIMAP was applied to map(ping) the Wadden Sea. Results for the Wadden Sea are taken up in the annexes. In this way, a good foundation has been laid for an elaborate ecotope system for the Dutch marinecartographies are added to this report as annexes. This provides a good basis for a completely elaborated ecotope system for the Dutch marine and estuarine waters.In het kader van de BEON-speerpunt Habitatverstoring werd al snel geconstateerd, dat het type vragen dat in dit verband gesteld kan worden alleen efficient kan worden aangepakt, wanneer men de beschikking heeft over een heldere, liefst geografische indeling van de zoute wateren van Nederland. Zo'n indeling, die al wel bestond voor terrestrische systemen en diverse typen zoete wateren, was niet beschikbaar voor zoute wateren. Het ontwikkelen van een systeem dat hiervoor gebruikt zou kunnen worden, werd daarom het hoofddoel van een van de onder deze speerpunt vallende projecten: Kartering habitats/ecotopen in de Nederlandse zoute wateren (laatste nummer: IBN 96 H 25). In deelstudies van dit project werd onderzocht welke (a)biotische factoren het voorkomen van bodemdieren en vissen in diverse zoute wateren bepaalden, en op welke wijze, en wat de samenstelling van die fauna's was. Een korte literatuurstudie naar definities en begrippen leidde tot het besluit, dat de nagestreefde indeling plaats zou moeten vinden op basis van ecotopen. In een apart deelproject werden criteria geformuleerd waarmee ecotopen zouden kunnen worden onderscheiden. Daarbij is onder meer informatie uit de andere deelstudies gebruikt, maar met name is gekeken naar processen die ecotopen vormen en instandhouden, naast factoren die relevant zijn voor de flora en fauna. Vervolgens is een hierarchisch systeem ontworpen van kenmerken van ecotopen, leidend tot een lijst van ecotopen. Er is daarbij gepoogd aan te sluiten bij reeds bestaande indelingen voor terrestrische en zoetwater-systemen. Er worden geen kenmerkklassen gegeven, omdat deze per onderscheiden ecotoop in verschillende watersystemen, en zelfs per doelstelling van een bepaalde studie, kunnen verschillen. De speciaal ontwikkelde GIS-applicatie HABIMAP is toegepast om op basis van dit stelsel van ecotopen een kartering van de Waddenzee uit te voeren. In twee niet onder BEON vallende projecten van Rijkswaterstaat zijn vergelijkbare karteringen uitgevoerd voor de Westerschelde en de Noordzee. De resultaten van deze drie karteringen zijn als bijlage bij dit rapport gevoegd. Hiermee is een goede basis gelegd voor een volledig uitgewerkt ecotopenstelsel voor de Nederlandse zoute watere

To a ecotope system for the Dutch marine and estuarine waters

In het kader van de BEON-speerpunt Habitatverstoring werd al snel geconstateerd, dat het type vragen dat in dit verband gesteld kan worden alleen efficient kan worden aangepakt, wanneer men de beschikking heeft over een heldere, liefst geografische indeling van de zoute wateren van Nederland. Zo'n indeling, die al wel bestond voor terrestrische systemen en diverse typen zoete wateren, was niet beschikbaar voor zoute wateren. Het ontwikkelen van een systeem dat hiervoor gebruikt zou kunnen worden, werd daarom het hoofddoel van een van de onder deze speerpunt vallende projecten: Kartering habitats/ecotopen in de Nederlandse zoute wateren (laatste nummer: IBN 96 H 25). In deelstudies van dit project werd onderzocht welke (a)biotische factoren het voorkomen van bodemdieren en vissen in diverse zoute wateren bepaalden, en op welke wijze, en wat de samenstelling van die fauna's was. Een korte literatuurstudie naar definities en begrippen leidde tot het besluit, dat de nagestreefde indeling plaats zou moeten vinden op basis van ecotopen. In een apart deelproject werden criteria geformuleerd waarmee ecotopen zouden kunnen worden onderscheiden. Daarbij is onder meer informatie uit de andere deelstudies gebruikt, maar met name is gekeken naar processen die ecotopen vormen en instandhouden, naast factoren die relevant zijn voor de flora en fauna. Vervolgens is een hierarchisch systeem ontworpen van kenmerken van ecotopen, leidend tot een lijst van ecotopen. Er is daarbij gepoogd aan te sluiten bij reeds bestaande indelingen voor terrestrische en zoetwater-systemen. Er worden geen kenmerkklassen gegeven, omdat deze per onderscheiden ecotoop in verschillende watersystemen, en zelfs per doelstelling van een bepaalde studie, kunnen verschillen. De speciaal ontwikkelde GIS-applicatie HABIMAP is toegepast om op basis van dit stelsel van ecotopen een kartering van de Waddenzee uit te voeren. In twee niet onder BEON vallende projecten van Rijkswaterstaat zijn vergelijkbare karteringen uitgevoerd voor de Westerschelde en de Noordzee. De resultaten van deze drie karteringen zijn als bijlage bij dit rapport gevoegd. Hiermee is een goede basis gelegd voor een volledig uitgewerkt ecotopenstelsel voor de Nederlandse zoute waterenIn the context of the Policy-oriented ecological research for the North Sea and Wadden Sea (BEON) spearhead study, "Habitat disturbance", it soon became apparent that the questions arising on habitat disturbance could only be approached efficiently when a clear, preferably geographical, classification of the Dutch marine and estuarine waters was available. Such a classification was already available for terrestrial systems and several types of fresh waters, but not for saline waters. For this reason, developing a system to be used for this purpose became the main occupation of the working group on "cartography of habitats/ecotopes in Dutch marine and estuarine waters". Partial studies concentrated on identifying the abiotic factors determining the occurrence of benthos and fish (and showing how the factors work), as well as the species composition of these groups. A short literature study led to the conclusion that the intended classification should be based on ecotopes, rather than habitats. Criteria to distinguish ecotopes were defined using information from the above-mentioned partial studies, but the main consideration was for processes forming and sustaining ecotopes, followed by factors with a specific relevance to flora and fauna. Next, a hierarchical system of ecotope characteristics was designed, leading to a list of ecotopes. An attempt was made to link up with existing classifications for terrestrial and freshwater systems. No classes for the characteristics are reported here, since these can vary per ecotope according to the different water systems under consideration, and even per defined purpose of a given study. The specially devised GIS application HABIMAP was applied to map(ping) the Wadden Sea. Results for the Wadden Sea are taken up in the annexes. In this way, a good foundation has been laid for an elaborate ecotope system for the Dutch marinecartographies are added to this report as annexes. This provides a good basis for a completely elaborated ecotope system for the Dutch marine and estuarine waters.DGM/BEO

Biogelx: cell culture on self-assembling peptide gels

Aromatic peptide amphiphiles can form self-supporting nanostructured hydrogels with tunable mechanical properties and chemical compositions. These hydrogels are increasingly applied in two-dimensional (2D) and three-dimensional (3D) cell culture, where there is a rapidly growing need to store, grow, proliferate, and manipulate naturally derived cells within a hydrated, 3D matrix. Biogelx Limited is a biomaterials company, created to commercialize these bio-inspired hydrogels to cell biologists for a range of cell culture applications. This chapter describes methods of various characterization and cell culture techniques specifically optimized for compatibility with Biogelx products

A multi-model ensemble of downscaled spatial climate change scenarios for the Dommel catchment, Western Europe

Regional or local scale hydrological impact studies require high resolution climate change scenarios which should incorporate some assessment of uncertainties in future climate projections. This paper describes a method used to produce a multi-model ensemble of multivariate weather simulations including spatial-temporal rainfall scenarios and single-site temperature and potential evapotranspiration scenarios for hydrological impact assessment in the Dommel catchment (1,350 km2) in The Netherlands and Belgium. A multi-site stochastic rainfall model combined with a rainfall conditioned weather generator have been used for the first time with the change factor approach to downscale projections of change derived from eight Regional Climate Model (RCM) experiments for the SRES A2 emission scenario for the period 2071-2100. For winter, all downscaled scenarios show an increase in mean daily precipitation (catchment average change of +9% to +40%) and typically an increase in the proportion of wet days, while for summer a decrease in mean daily precipitation (-16% to -57%) and proportion of wet days is projected. The range of projected mean temperature is 7.7°C to 9.1°C for winter and 19.9°C to 23.3°C for summer, relative to means for the control period (1961-1990) of 3.8°C and 16.8°C, respectively. Mean annual potential evapotranspiration is projected to increase by between +17% and +36%. The magnitude and seasonal distribution of changes in the downscaled climate change projections are strongly influenced by the General Circulation Model (GCM) providing boundary conditions for the RCM experiments. Therefore, a multi-model ensemble of climate change scenarios based on different RCMs and GCMs provides more robust estimates of precipitation, temperature and evapotranspiration for hydrological impact assessments, at both regional and local scale