a new Pc-C boundary section

The widespread, terminal Ediacaran Dengying Formation (~ 551–~ 542 Ma) of South China hosts one of the most prominent negative carbonate carbon isotope excursions in Earth's history and thus bears on the correlation of the Precambrian–Cambrian boundary worldwide. The dominantly carbonate strata of the Dengying Formation are largely studied for their unique preservation of its terminal Ediacaran fauna but their geochemical context is poorly known. This study presents the first high-resolution stable isotope record (δ13C, δ18O) of calcareous siliciclastic shallow-water deposits of the Gaojiashan section (Shaanxi Province). The section includes (in ascending order) the Algal Dolomite Member, the Gaojiashan Member and the Beiwan Member of the Dengying Formation. Our data record a major δ13Ccarb negative excursion to −6 ‰ in the uppermost Gaojiashan Member which is comparable in shape and magnitude to the global Precambrian–Cambrian boundary negative δ13C excursion. Our data set is consistent with a "shallow-water anoxia" scenario which is thought to contribute to the "Cambrian explosion". The stratigraphic occurrence of Cloudina and a large negative δ13C excursion suggest that the Precambrian–Cambrian boundary is located near the top of the Gaojiashan Member and, consequently, that overlying carbonates and dolomites of the Beiwan Member are of earliest Cambrian age. Thus the Gaojiashan section may represent a new shallow-water section spanning the Precambrian–Cambrian boundary. Although bio- and chemostratigraphic data support this novel interpretation, we cannot exclude the possibility that the key excursions may represent a local perturbation indicating a restricted-basin environment

Phytocoenotic originality of the N-Adriatic coastal sand dunes (Northern Italy) in the European context: The Stipa veneta-rich communities.

The particular habitat of Stipa veneta, a priority species of the European Community Directive 92/43, is here described. The phytosociological analysis led to the description of a new association ( Teucrio capitati-Chrysopogonetum grylli), endemic of the N-Adriatic fixed sand dunes. Given the high importance of the species, the conservation of its specific community should be included in a broad protection plan of this unique coastal system in the European context

Valutazione della qualità e dello stato di conservazione degli ambienti litoranei: l'esempio del pS.I.C. "Penisola del Cavallino: biotopi litoranei" (Venezia, NE-Italia)

Evaluation of quality and conservation status in coastal landscapes: the example of the Site of Community Importance “Penisola del Cavallino: biotopi litoranei”(Venice, NE Italy). Quality of coastal landscape has been estimated at two different scale: at the community level, we assessed a naturalistic value, by evaluating characteristics coming both from species (i.e. presence of endemic species) and from community itself (i.e. rarity). We also took into account the percentage of exotic and ruderal species on the total number of species of each community, as an indirect measure of alteration degree. At the landscape level, we tried to value structural and functional integrity by evaluating spatial connectivity and contrast among patches. As the plant communities of foredunes show a typical spatial zonation, the two indices have been calculated along 27 transects perpendicular to the seashore. On the basis of a digital map of the area, we measured the gamma connectivity index along each transect; we assessed both “total connectivity”, considering all the communities intersected by the transects, and “partial connectivity”, considering only the plant communitie s of foredunes, so describing spatial distribution model of coastal vegetation. Since on the backdune there is not a typical zonation of communiti es, we counted only the links between natural communities, considering anthropogenic communities as a break of natural landscape and of connectivity. I n addition, we measured the contrast index; this index evaluates the change in environmental conditions going from one community (or patch) to the neighbouring one. The different patches are included and surrounded by a matrix, consisting of “nonhabitat” at different degree of alteratio n, that may function as an impenetrable barrier for individuals or, on the contrary, may favour movements. Thus, the surrounding matrix may significant ly influence the effective isolation of habitat patches, rendering them more or less isolated than simple distance would indicate. For the contr ast computation, we utilized the naturalistic value assessed to each community on the basis of the phytosociological data. Both indices point to the extreme fragmentation of coastal landscape and to high vulnerability that characterizes all natural communities being they surrounded by a matrix hig hly contrasting. Conservation strategies should, then, concern natural habitat, their quality and their structural and functional integrity, but they should also consider the quality of surrounding matrix

Phytocoenotic diversity of the N-Adriatic coastal sand dunes - The herbaceous communities of the fixed dunes and the vegetation of the interdunal wetlands

The hemicryptophytic, chamaephytic and therophytic communities which inhabit the fixed sand dunes of the N-Adriatic coast, along with those of the interdunal wetlands, have been studied from the phytosociological point of view. The floristic-sociological analysis focuses on the syntaxonomic discussion of the xerophilous communities; in this context, the following new syntaxa have been described: Syntrichio ruraliformis-Lomelosion argenteae, Tortulo-Scabiosetum typicum and Sileno conicae-Avellinietum michelii. In regards to the dune slack vegetation, the study points out the occurrence in the coastal area of two rare inland microtherm communities (Plantagini altissimae-Molinietum caeruleae and Erucastro-Schoenetum nigricantis). As already stated in previous papers, the originality of this sector of the Mediterranean basin is highlighted as a result of both bioclimatic and phytogeographic factors, which confer to this area a unique character in the European context

The ALPS project release 1.3: open source software for strongly correlated systems

We present release 1.3 of the ALPS (Algorithms and Libraries for Physics Simulations) project, an international open source software project to develop libraries and application programs for the simulation of strongly correlated quantum lattice models such as quantum magnets, lattice bosons, and strongly correlated fermion systems. Development is centered on common XML and binary data formats, on libraries to simplify and speed up code development, and on full-featured simulation programs. The programs enable non-experts to start carrying out numerical simulations by providing basic implementations of the important algorithms for quantum lattice models: classical and quantum Monte Carlo (QMC) using non-local updates, extended ensemble simulations, exact and full diagonalization (ED), as well as the density matrix renormalization group (DMRG). Changes in the new release include a DMRG program for interacting models, support for translation symmetries in the diagonalization programs, the ability to define custom measurement operators, and support for inhomogeneous systems, such as lattice models with traps. The software is available from our web server at http://alps.comp-phys.org/

Publisher Correction: Coupling of ocean redox and animal evolution during the Ediacaran-Cambrian transition

Correction to: Nature Communications https://doi.org/10.1038/s41467-018-04980-5; published online: 03 July 2018 The original version of this Article incorrectly gave the second address in the list of affiliations as “State Key Laboratory of Palaeobiology and Stratigraphy & Center for Excellence in Life and Paleoenvironment, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 210008 Nanjing, China”, instead of the correct ‘State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China”. This has been corrected in both the PDF and HTML versions of the Article

Kv7 Channels Can Function without Constitutive Calmodulin Tethering

M-channels are voltage-gated potassium channels composed of Kv7.2-7.5 subunits that serve as important regulators of neuronal excitability. Calmodulin binding is required for Kv7 channel function and mutations in Kv7.2 that disrupt calmodulin binding cause Benign Familial Neonatal Convulsions (BFNC), a dominantly inherited human epilepsy. On the basis that Kv7.2 mutants deficient in calmodulin binding are not functional, calmodulin has been defined as an auxiliary subunit of Kv7 channels. However, we have identified a presumably phosphomimetic mutation S511D that permits calmodulin-independent function. Thus, our data reveal that constitutive tethering of calmodulin is not required for Kv7 channel function