Role of Astrocytes in Neurovascular Coupling

Neural activity is intimately tied to blood flow in the brain. This coupling is specific enough in space and time that modern imaging methods use local hemodynamics as a measure of brain activity. In this review, we discuss recent evidence indicating that neuronal activity is coupled to local blood flow changes through an intermediary, the astrocyte. We highlight unresolved issues regarding the role of astrocytes and propose ways to address them using novel techniques. Our focus is on cellular level analysis in vivo, but we also relate mechanistic insights gained from ex vivo experiments to native tissue. We also review some strategies to harness advances in optical and genetic methods to study neurovascular coupling in the intact brain

zfishbook: connecting you to a world of zebrafish revertible mutants

zfishbook is an internet-based openly accessible database of revertible protein trap gene-breaking transposon (GBT) insertional mutants in the zebrafish, Danio rerio. In these lines, a monomeric red fluorescent protein (mRFP) is encoded by an artificial 3′ exon, resulting in a translational fusion to endogenous loci. The natural transparency of the zebrafish embryo and larvae greatly facilitates the expression annotation of tagged loci using new capillary-based SCORE imaging methods. Molecular annotation of each line is facilitated by cloning methods such as 5′-Rapid Amplification of cDNA Ends (RACE) and inverse polymerase chain reaction (PCR). zfishbook (http://zfishbook.org) represents a central hub for molecular, expression and mutational information about GBT lines from the International Zebrafish Protein Trap Consortium (IZPTC) that includes researchers from around the globe. zfishbook is open to community-wide contributions including expression and functional annotation. zfishbook also represents a central location for information on how to obtain these lines from diverse members of the IZPTC and integration within other zebrafish community databases including Zebrafish Information Network (ZFIN), Ensembl and National Center for Biotechnology Information

Hyperextended Scalar-Tensor Gravity

We study a general Scalar-Tensor Theory with an arbitrary coupling funtion $\omega (\phi )$ but also an arbitrary dependence of the ``gravitational constant'' $G(\phi )$ in the cases in which either one of them, or both, do not admit an analytical inverse, as in the hyperextended inflationary scenario. We present the full set of field equations and study their cosmological behavior. We show that different scalar-tensor theories can be grouped in classes with the same solution for the scalar field.Comment: latex file, To appear in Physical Review

Some exact non-vacuum Bianchi VI0 and VII0 instantons

We report some new exact instantons in general relativity. These solutions are K\"ahler and fall into the symmetry classes of Bianchi types VI0 and VII0, with matter content of a stiff fluid. The qualitative behaviour of the solutions is presented, and we compare it to the known results of the corresponding self-dual Bianchi solutions. We also give axisymmetric Bianchi VII0 solutions with an electromagnetic field.Comment: latex, 15 pages with 3 eps figure

Active job monitoring in pilots

Recent developments in high energy physics (HEP) including multi-core jobs and multi-core pilots require data centres to gain a deep understanding of the system to monitor, design, and upgrade computing clusters. Networking is a critical component. Especially the increased usage of data federations, for example in diskless computing centres or as a fall-back solution, relies on WAN connectivity and availability. The specific demands of different experiments and communities, but also the need for identification of misbehaving batch jobs, requires an active monitoring. Existing monitoring tools are not capable of measuring fine-grained information at batch job level. This complicates network-aware scheduling and optimisations. In addition, pilots add another layer of abstraction. They behave like batch systems themselves by managing and executing payloads of jobs internally. The number of real jobs being executed is unknown, as the original batch system has no access to internal information about the scheduling process inside the pilots. Therefore, the comparability of jobs and pilots for predicting run-time behaviour or network performance cannot be ensured. Hence, identifying the actual payload is important. At the GridKa Tier 1 centre a specific tool is in use that allows the monitoring of network traffc information at batch job level. This contribution presents the current monitoring approach and discusses recent e_orts and importance to identify pilots and their substructures inside the batch system. It will also show how to determine monitoring data of specific jobs from identified pilots. Finally, the approach is evaluated

Economic burden of female genital mutilation in 27 high-prevalence countries

Background: Female genital mutilation (FGM) is a traditional harmful practice affecting 200 million women and girls globally. Health complications of FGM occur immediately and over time, and are associated with healthcare costs that are poorly understood. Quantifying the global FGM-related burden is essential for supporting programmes and policies for prevention and mitigation. / Methods: Health complications of FGM are derived from a meta-analysis and stratified by acute, uro-gynaecological, obstetric and psychological/sexual. Treatment costs are calculated from national cohort models of 27 high-burden countries over 30 years. Savings associated with full/partial abandonment are compared with a current incidence reference scenario, assuming no changes in FGM practices. / Results: Our model projects an increasing burden of FGM due to population growth. As a reference scenario assuming no change in practices, prevalent cases in 27 countries will rise from 119.4 million (2018) to 205.8 million (2047). Full abandonment could reduce this to 80.0 million (2047), while partial abandonment is insufficient to reduce cases. Current incidence economic burden is US$1.4 billion/year, rising to US$2.1 billion/year in 2047. Full abandonment would reduce the future burden to US$0.8 billion/year by 2047. / Conclusion: FGM is a human rights violation, a public health issue and a substantial economic burden that can be avoided through effective prevention strategies. While decreasing trends are observed in some countries, these trends are variable and not consistently observed across settings. Additional resources are needed to prevent FGM to avoid human suffering and growing costs. The findings of this study warrant increased political commitment and investment in the abandonment of FGM

Volatile particles formation during PartEmis: a modelling study

A modelling study of the formation of volatile particles in a combustor exhaust has been carried out in the frame of the PartEmis European project. A kinetic model has been used in order to investigate nucleation efficiency of the H₂O-H₂SO₄ binary mixture in the sampling system. A value for the fraction <IMG WIDTH='10' HEIGHT='13' ALIGN='BOTTOM' BORDER='0' src='http://www.atmos-chem-phys.net/4/439/2004/acp-4-439-img1.gif' ALT='$varepsilon$'> of the fuel sulphur S(IV) converted into S(VI) has been indirectly deduced from comparisons between model results and measurements. In the present study, <IMG WIDTH='10' HEIGHT='13' ALIGN='BOTTOM' BORDER='0' src='http://www.atmos-chem-phys.net/4/439/2004/acp-4-439-img1.gif' ALT='$varepsilon$'> ranges between roughly 2.5% and 6%, depending on the combustor settings and on the value assumed for the parameter describing sulphuric acid wall losses. Soot particles hygroscopicity has also been investigated as their activation is a key parameter for contrail formation. Growth factors of monodisperse particles exposed to high relative humidity (95%) have been calculated and compared with experimental results. The modelling study confirms that the growth factor increases as the soot particle size decreases

Quel modèle d’émergence pour les start-up des éco-industries : David un futur Goliath ou David avec Goliath ?

Dans les industries verdissantes, des start-up, tels des "David" tentent de trouver leur place à côté des "Goliath" qui mettent du vert dans leur stratégie. Quel modèle d’émergence ces start-up sont-elles en mesure d’adopter? Pour répondre à cette question deux lectures complémentaires sont proposées : celle en termes de design dominant et celle de type évolutionniste. Un cas de l’éco-industrie en France permet d’étudier en profondeur le cheminement stratégique d’une start-up. Les résultats mettent en évidence des facteurs de contingence qui pousseraient les start-up des éco-industries soit vers un modèle soit vers l’autre