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The olivine-wadsleyite transformation is believed to occur at depths of about 410 km in the Earth, producing a major seismic discontinuity in this region of the Earth’s mantle. The mechanism of this phase transition controls the microstructures of the newly-nucleated wadsleyite, the major phase of the upper part of the mantle transition zone, and thus impacts seismic observations in the region. Here, we study the microstructures produced by the olivine-wadsleyite transformation using in-situ laboratory experiments at pressures and temperatures relevant for the mantle transition zone. We transform pure olivine samples in laser-heated diamond anvil cells at pressures ranging from 12.3 to 20.2 GPa and temperatures of 1400-1730 K. At different steps of the transformation we measure the orientation and size distribution of individual sample grains using multigrain crystallography at synchrotron radiation sources. We find that the olivine to wadsleyite transformation is incoherent at the conditions of the mantle transition zone, and is probably dominated by nucleation of wadsleyite at grain boundaries of the parent olivine. Thus, we expect that seismic anisotropy near 410 km would drop significantly due to the randomized lattice preferred orientation of newly-nucleated wadsleyite induced by the incoherent transformation.

By 30 June 2021, EU Member States were expected to transpose the recast Renewable Energy Directive (RED II) which includes provisions for renewable energy communities (RECs) and to develop an enabling framework to promote the development of RECs. Although there is a growing number of studies analysing the emergence of various forms of community energy, comparative studies investigating the transposition and creation of enabling frameworks for RECs in a multi-level governance (MLG) perspective are scarce. This article examines the transposition in Germany and Italy and compares elements of the respective enabling frameworks. Key methods include context and MLG analysis combined with methods of descriptive (legal) studies. Insights and participatory observations of the stakeholder desks established in the Horizon2020 project COME RES complement the spectrum of methods deployed. Although community energy development is more advanced in Germany, the transposition of the RED II provisions has been slow and piecemeal so far. Conversely, in Italy, RED II played a catalyst role; the transposition has been rather dynamic and encouraged a continuous growth of REC initiatives. Nevertheless, a widespread uptake of RECs requires structural adjustments of the governance system in both countries and attention to MLG as well as vertical policy coordination.

Two years have passed since the Multidisciplinary Expert Panel and the Bureau of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) approved the IPBES Data Management Policy (https://doi.org/10.5281/zenodo.3551078). Since then, the policy has been implemented within the Platform and revised to explicitly include considerations of the handling of indigenous and local knowledge. Inclusivity and collective benefit as it relates to open science are now recognized as guiding principles in the policy. To inform implementation, the CARE Principles for Indigenous Data Governance now compliments the FAIR guiding principles for scientific data management and stewardship. With the inclusion of these concepts and responsibilities, the IPBES data management policy has been renamed to the IPBES data and knowledge management policy. The policy aims to improve the accessibility of products, transparency of the underlying processes to create them, and the CAREful handling of ILK within IPBES. In this contribution, we seek to inform the community about the latest development of the IPBES data and knowledge management policy, the progress to date with the implementation of the policy, and emerging projects., Presented at WORLD BIODIVERSITY FORUM 2022 - DAVOS, SWITZERLAND - JUNE 26 - JULY 1, 2022 https://www.worldbiodiversityforum.org/

Many nonmetals and metal dioxides MO2, including the dense form of SiO2 stishovite, crystalize in a rutile structure at low pressure and transform to a denser CaCl2 structure under high pressure. Structures and transformations in MO2 dioxides hence serve as an archetype for applications in materials science and inside the Earth and terrestrial planets. Despite its significance, however, the deformation behavior of MO2 compounds in the CaCl2 structure is very poorly constrained. Here we use radial x-ray diffraction in a diamond-anvil cell and study MnO2 as a representative system of the MO2 family. We identify the dominant slip systems and constrain texture evolution in CaCl2-structured phases. After phase transition to a CaCl2 structure above 3.5 GPa, the dominant (010)[100] and secondary {110}[001] and {011}[0-11] slip systems induce a 121 texture in compression. Further compression increases the activity of the {011}⟨0−11⟩ slip system, with an enhanced 001 texture at ∼50GPa. During pressure release, the 001 texture becomes dominant over the original 121 texture. This clearly demonstrates the effect of pressure on the deformation behavior and slip systems of CaCl2-structured dioxides. Finally, MnO2 transforms back to a rutile structure upon pressure release, with a significant orientation memory, highlighting the martensitic nature of the CaCl2 to rutile structural transformation. These findings provide key guidance regarding the plasticity of CaCl2-structured dioxides, with implications in materials and Earth and planetary science. 6

Ocean boundary current systems are key components of the climate system, are home to highly productive ecosystems, and have numerous societal impacts. Establishment of a global network of boundary current observing systems is a critical part of ongoing development of the Global Ocean Observing System. The characteristics of boundary current systems are reviewed, focusing on scientific and societal motivations for sustained observing. Techniques currently used to observe boundary current systems are reviewed, followed by a census of the current state of boundary current observing systems globally. Next steps in the development of boundary current observing systems are considered, leading to several specific recommendations.

Madagascar's southern coastal marine zone is a region of high biological productivity which supports a wide range of marine ecosystems, including fisheries. This high biological productivity is attributed to coastal up-welling. This paper provides new insights on the structure, variability and drivers of the coastal upwelling south of Madagascar. Satellite remote sensing is used to characterize the spatial extent and strength of the coastal upwelling. A front detection algorithm is applied to thirteen years of Multi-scale Ultra-high Resolution (MUR) Sea Surface Temperatures (SST) and an upwelling index is calculated. The influence of winds and ocean currents as drivers of the upwelling is investigated using satellite, in-situ observations, and a numerical model. Results reveal the presence of two well-defined upwelling cells. The first cell (Core 1) is located in the southeastern corner of Madagascar, and the second cell (Core 2) is west of the southern tip of Madagascar. These two cores are characterized by different seasonal variability, different intensities, different upwelled water mass origins, and distinct forcing mechanisms. Core 1 is associated with a dynamical upwelling forced by the detachment of the East Madagascar Current (EMC), which is reinforced by upwelling favourable winds. Core 2 appears to be primarily forced by upwelling favourable winds, but is also influenced by a poleward eastern boundary flow coming from the Mozambique Channel. The intrusion of Mozambique Channel warm waters could result in an asynchronicity in seasonality between upwelling surface signature and upwelling favourables winds.

International audience; Gliders were deployed for the first time in the Agulhas Current region to investigate processes of interactions between western boundary currents and shelf waters. Continuous observations from the gliders in water depths of 100-1000 m and over a period of 1 month provide the first high-resolution observations of the Agulhas Current's inshore front. The observations collected in a nonmeandering Agulhas Current show the presence of submesoscale cyclonic eddies, generated at the inshore boundary of the Agulhas Current. The submesoscale cyclones are often associated with warm water plumes, which extend from their western edge and exhibit strong northeastward currents. These features are a result of shear instabilities and extract their energy from the mean Agulhas Current jet.

This study re-investigates the work of Lutjeharms et al. [2001,2003] who documented the properties of a Natal Pulse using isopycnal Lagrangian floats. We combined Lagrangian analyses and Eulerian maps derived from objective analysis to better describe the evolution of a Natal Pulse along three density surfaces referred to as the surface (satellite-observed), shallow (isopycnal-1026.8 kg.m−3) and deep (isopycnal-1027.2 kg.m−3) layer. Our observations show that this Natal Pulse extended to a depth of 1000m and was associated with cyclonic relative vorticity values of about 6.5 to 8.5x10−5.s−1 in the surface and shallow layer and 4x10−5.s−1 in the deep layer. This Natal Pulse contributed to cross-shelf exchange through the offshore advection of Eastern Agulhas Bank water near the surface, onshore advection of South Indian Central Water and/or Indian Equatorial Water in the shallow layer and Antarctic Intermediate Water in the deep layer. Sea Surface Temperature maps showed that the downstream progression of the Natal Pulse along the 3000m isobath was related to a readjustment of its rotation axis. This readjustment advected Eastern Agulhas Bank water into the Natal Pulse eddy and triggered a SST cooling of about 3°C in the cyclonic area. The importance of a warm recirculating Agulhas plume originating from the Natal Pulse was highlighted. This warm water plume extended to a depth of 700m and was associated with onshore velocities exceeding those experienced within the Natal Pulse eddy by a factor of two. Our observations indicate that the June/July 1998 Natal Pulse and its associated plumes enhanced cross-shelf exchanges. This article is protected by copyright. All rights reserved.

XDSAPP is an expert system and graphical user interface (GUI) for the automated processing of diffraction images using the XDS program suite and other programs. The latest major update and the extension of the program are presented here. The update includes new features, as well as improvements in the GUI and the underlying decision-making system. XDSAPP is freely available for academic users.

Ocean models show an annual cycle in the Agulhas Current transport which has not yet been confirmed in analyses of in-situ or satellite observations. A cross-stream coordinate approach is used to study the variability of the Agulhas Current from 18 years of along-track altimetry and merged altimetry and close to 7 years of high frequency Sea Surface Temperature (SST) observations. While the position and width of the Agulhas Current's dynamical core do not display an annual cycle, the geostrophic current speed at the current's core exhibits distinct seasonal variations, with a stronger flow observed in austral summer. The annual cycle dominates the frequency spectra of the current's core geostrophic velocities. Citation: Krug, M., and J. Tournadre (2012), Satellite observations of an annual cycle in the Agulhas Current, Geophys. Res. Lett., 39, L15607, doi:10.1029/2012GL052335.

The infiltration of dissolved dies into vertically aligned carbon nanotube arrays (VA-CNT) is reported. The ultra hydrophobic surface of a CNT array can be completely infiltrated on a surface area of 48 mm2 by an appropriate choice of solvent. This is so far not possible by evaporation techniques. Depending on the solvent type, the CNT alignment remains unaltered, which is strongly modified, or even lost. The infiltrated CNT array provides a well ordered electrode structure for organic solar cells. The CNT can simultaneously serve as electron acceptor in combination with an appropriate donor dye. Sensors and organic LED are among further applications.

We report the observation of entanglement between a single trapped atom and a single photon at remote locations. The degree of coherence of the entangled atom-photon pair is verified via appropriate local correlation measurements, after communicating the photon via an optical fiber link of 300 m length. In addition we measured the temporal evolution of the atomic density matrix after projecting the atom via a state measurement of the photon onto several well defined spin states. We find that the state of the single atom dephases on a timescale of 150 $\mu$s, which represents an important step toward long-distance quantum networking with individual neutral atoms., Comment: 4 pages, 4 figures

We report on an 5-year-old boy with a Proteus syndrome known since his second year of life. Hidden in a lipomatous tumor we excised a sacrococcygeal teratoma which must have been present since birth. This is the first case, out of about 50 published Proteus cases, of a patient with Proteus syndrome and sacrococcygeal teratoma. 6 4 249 251