Axin2 as regulatory and therapeutic target in newborn brain injury and remyelination.

Permanent damage to white matter tracts, comprising axons and myelinating oligodendrocytes, is an important component of brain injuries of the newborn that cause cerebral palsy and cognitive disabilities, as well as multiple sclerosis in adults. However, regulatory factors relevant in human developmental myelin disorders and in myelin regeneration are unclear. We found that AXIN2 was expressed in immature oligodendrocyte progenitor cells (OLPs) in white matter lesions of human newborns with neonatal hypoxic-ischemic and gliotic brain damage, as well as in active multiple sclerosis lesions in adults. Axin2 is a target of Wnt transcriptional activation that negatively feeds back on the pathway, promoting β-catenin degradation. We found that Axin2 function was essential for normal kinetics of remyelination. The small molecule inhibitor XAV939, which targets the enzymatic activity of tankyrase, acted to stabilize Axin2 levels in OLPs from brain and spinal cord and accelerated their differentiation and myelination after hypoxic and demyelinating injury. Together, these findings indicate that Axin2 is an essential regulator of remyelination and that it might serve as a pharmacological checkpoint in this process

Walk on the Wild Side: Estimating the Global Magnitude of Visits to Protected Areas

How often do people visit the world’s protected areas (PAs)? Despite PAs covering one-eighth of the land and being a major focus of nature-based recreation and tourism, we don’t know. To address this, we compiled a globally-representative database of visits to PAs and built region-specific models predicting visit rates from PA size, local population size, remoteness, natural attractiveness, and national income. Applying these models to all but the very smallest of the world’s terrestrial PAs suggests that together they receive roughly 8 billion (8 x 109) visits/y—of which more than 80% are in Europe and North America. Linking our region-specific visit estimates to valuation studies indicates that these visits generate approximately US $600 billion/y in direct in-country expenditure and US$250 billion/y in consumer surplus. These figures dwarf current, typically inadequate spending on conserving PAs. Thus, even without considering the many other ecosystem services that PAs provide to people, our findings underscore calls for greatly increased investment in their conservation.This study was supported by The Natural Capital Project (http://www.naturalcapitalproject.org/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.This is the final published version. It first appeared at http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1002074

Origin of chemical and dynamical properties of the Galactic thick disk

We adopt a scenario in which the Galactic thick disk was formed by minor merging between the first generation of the Galactic thin disk (FGTD) and a dwarf galaxy about 9 Gyr ago and thereby investigate chemical and dynamical properties of the Galactic thick disk. In this scenario, the dynamical properties of the thick disk have long been influenced both by the mass growth of the second generation of the Galactic thin disk (i.e., the present thin disk) and by its non-axisymmetric structures. On the other hand, the early star formation history and chemical evolution of the thin disk was influenced by the remaining gas of the thick disk. Based on N-body simulations and chemical evolution models, we investigate the radial metallicity gradient, structural and kinematical properties, and detailed chemical abundance patterns of the thick disk. Our numerical simulations show that the ancient minor merger event can significantly flatten the original radial metallicity gradient of the FGTD, in particular, in the outer part, and also can be responsible for migration of inner metal-rich stars into the outer part (R>10kpc). The simulations show that the central region of the thick disk can develop a bar due to dynamical effects of a separate bar in the thin disk. The simulated orbital eccentricity distributions in the thick disk for models with higher mass-ratios (~0.2) and lower orbital eccentricities (~ 0.5) of minor mergers are in good agreement with the corresponding observations. The simulated V_{phi}-|z| relation of the thick disk in models with low orbital inclination angles of mergers are also in good agreement with the latest observational results. Our Galactic chemical evolution models can explain both the observed metallicity distribution functions (MDFs) and correlations between [Mg/Fe] and [Fe/H] for the two disks in a self-consistent manner.Comment: 19 pages, 22 figures, accepted in Ap

Early responses to H7N9 in southern mainland China

This article is made available through the Brunel Open Access Publishing Fund. © 2014 Goodwin and Sun; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: H7N9 posed potentially serious health challenges for Chinese society. The previous SARS outbreak in this country was accompanied by contradictory information, while worries about wide-spread influenza led to discrimination worldwide. Early understanding of public threat perceptions is therefore important for effective public health communication and intervention. Methods: We interviewed 1011 respondents by phone two weeks after the first case. Questions examined risk awareness and media use, beliefs about the emergence of the threat and those most at risk, anxiety about infection and preventive and avoidant behaviours. Results: Results demonstrate moderate levels of anxiety but relatively high levels of trust towards government officials. Threat emergence was associated with hygiene levels, temperature change, floating pigs in the Huangpu River and migration to the city. Anxiety predicted both recommended and non-recommended behavioural changes. Conclusions: Comparatively high levels of trust in Chinese government advice about H7N9 contrast positively with previous pandemic communications in China. Anxiety helped drive both recommended and non-recommended behaviours, with potentially important economic and social implications. This included evidence of 'othering’ of those associated with the threat (e.g. migrants). Findings emphasise the need to manage public communications early during new influenza outbreaks.Fudan Tydall Centre and Fudan Media and Public Opinion Center

The fraction of binary systems in the core of thirteen low-density Galactic globular clusters

We used deep observations collected with ACS@HST to derive the fraction of binary systems in a sample of thirteen low-density Galactic globular clusters. By analysing the color distribution of Main Sequence stars we derived the minimum fraction of binary systems required to reproduce the observed color-magnitude diagram morphologies. We found that all the analysed globular clusters contain a minimum binary fraction larger than 6% within the core radius. The estimated global fractions of binary systems range from 10% to 50% depending on the cluster. A dependence of the relative fraction of binary systems on the cluster age has been detected, suggesting that the binary disruption process within the cluster core is active and can significantly reduce the binary content in time.Comment: 12 pages, 10 figures, accepted for publication by MNRA

Bicontinuous minimal surface nanostructures for polymer blend solar cells

This paper presents the first examination of the potential for bicontinuous structures such as the gyroid structure to produce high efficiency solar cells based on conjugated polymers. The solar cell characteristics are predicted by a simulation model that shows how the morphology influences device performance through integration of all the processes occurring in organic photocells in a specified morphology. In bicontinuous phases, the surface de. ning the interface between the electron and hole transporting phases divides the volume into two disjoint subvolumes. Exciton loss is reduced because the interface at which charge separation occurs permeates the device so excitons have only a short distance to reach the interface. As each of the component phases is connected, charges will be able to reach the electrodes more easily. In simulations of the current-voltage characteristics of organic cells with gyroid, disordered blend and vertical rod (rods normal to the electrodes) morphologies, we find that gyroids have a lower than anticipated performance advantage over disordered blends, and that vertical rods are superior. These results are explored thoroughly, with geminate recombination, i.e. recombination of charges originating from the same exciton, identified as the primary source of loss. Thus, if an appropriate materials choice could reduce geminate recombination, gyroids show great promise for future research and applications

Walk on the wild side: estimating the global magnitude of visits to protected areas.

How often do people visit the world's protected areas (PAs)? Despite PAs covering one-eighth of the land and being a major focus of nature-based recreation and tourism, we don't know. To address this, we compiled a globally-representative database of visits to PAs and built region-specific models predicting visit rates from PA size, local population size, remoteness, natural attractiveness, and national income. Applying these models to all but the very smallest of the world's terrestrial PAs suggests that together they receive roughly 8 billion (8 x 109) visits/y-of which more than 80% are in Europe and North America. Linking our region-specific visit estimates to valuation studies indicates that these visits generate approximately US $600 billion/y in direct in-country expenditure and US$250 billion/y in consumer surplus. These figures dwarf current, typically inadequate spending on conserving PAs. Thus, even without considering the many other ecosystem services that PAs provide to people, our findings underscore calls for greatly increased investment in their conservation.This study was supported by The Natural Capital Project (http://www.naturalcapitalproject.org/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.This is the final published version. It first appeared at http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1002074