To assess the time scales and relative importance of temporal decoupling between hillslope erosion and the introduction of sediment to streams in a Yangtze River headwater basin, we used multiple techniques to date sediments in alluvial fans and terraces in a third-order stream valley draining a 30-km2 catchment in SW Sichuan, China. Poorly sorted angular sediments in tributary-junction alluvial fans ranged in age from 11261 BCE to 1844 CE, and predominantly fine-grained overbank sediments in alluvial terraces date to approximately 1700–1950. Ethnographic observations and field mapping of hillslope soil depths indicate that terrace sediments and upper strata of several fans correspond to a period of hillslope erosion associated with the intensification of hillslope swidden agriculture. Contemporary sediment production is dominated by lateral fluvial erosion of valley-bottom landforms rather than by hillslope erosion. The long-term temporal decoupling by valley storage of hillslope erosion from sediment delivery to streams has relevance to contemporary hillslope erosion and sedimentation control efforts in the Yangtze Basin. It also motivates investigating whether valley-filling anthropogenic “legacy sediments” may play a role in decoupling hillslope erosion from sediment production in other Yangtze Basin headwater basins.

Quantum field theory predicts a nonlinear response of the vacuum to strong electromagnetic fields of macroscopic extent. This fundamental tenet has remained experimentally challenging and is yet to be tested in the laboratory. A particularly distinct signature of the resulting optical activity of the quantum vacuum is vacuum birefringence. This offers an excellent opportunity for a precision test of nonlinear quantum electrodynamics in an uncharted parameter regime. Recently, the operation of the high-intensity Relativistic Laser at the X-ray Free Electron Laser provided by the Helmholtz International Beamline for Extreme Fields has been inaugurated at the High Energy Density scientific instrument of the European X-ray Free Electron Laser. We make the case that this worldwide unique combination of an X-ray free-electron laser and an ultra-intense near-infrared laser together with recent advances in high-precision X-ray polarimetry, refinements of prospective discovery scenarios and progress in their accurate theoretical modelling have set the stage for performing an actual discovery experiment of quantum vacuum nonlinearity.

We examine the Holocene loess record in the Heye Catchment on the margins of the Tibetan Plateau (TP) and China Loess Plateau (CLP) to determine: the region to which the Heye Catchment climate is more similar; temporal change in wind strength; and modification of the loess record by mass wasting and human activity. Luminescence and radiocarbon dating demonstrate loess deposited in two periods: >11–8.6 ka and <5.1 ka. The 8.6–5.1 ka depositional hiatus, which coincides with the Mid-Holocene Climatic Optimum, is more similar to the loess deposition cessation in the TP than to the loess deposition deceleration in the CLP. Grain-size analysis suggests the Heye loess is a mixture of at least three different grain-size distributions and that it may derive from multiple sources. A greater proportion of coarse sediments in the older loess may indicate stronger winds compared with the more recent depositional period. Gravel incorporated into younger loess most likely comes from bedrock exposed in slump scarps. Human occupation of the catchment, for which the earliest evidence is 3.4 ka, postdates the onset of slumping; thus the slumps may have created a livable environment for humans.

Background: Hereditary transthyretin-mediated (hATTR) amyloidosis is a multi-systemic, heterogenous, life-threatening disease. Patisiran resulted in significant improvement in neuropathy and QoL at 18-months compared to placebo, and was generally well-tolerated in the Phase 3 APOLLO study. Methods: Multi-center, OLE study to evaluate the efficacy and safety of long-term patisiran dosing for ≤ 5 years in hATTR amyloidosis patients with polyneuropathy who have completed the APOLLO study (NCT02510261). Endpoints include safety, tolerability and long-term efficacy of patisiran. Measures of clinical benefit are the same endpoints used in APOLLO including changes in mNIS+7 composite neuropathy impairment score and QoL (Norfolk QoL-DN) Results: As of December 2017, 184 of 186 (99%) patients who completed APOLLO and 25 patients from the Ph 2 OLE study enrolled in the Global OLE study. Baseline data for 211(APOLLO/placebo, n=49; APOLLO/patisiran, n=137 and patisiran Ph 2 OLE, n=25) patients included: median age 61 years (26-84); 74% males; 46% V30M. Interim safety data and 12-month efficacy results will be presented. Conclusions: The global OLE study includes a diverse population of hATTR amyloidosis patients. Interim data will include the long-term safety and maintenance of effect in patients continuing on patisiran, as well as the impact of treatment with patisiran on patients previously treated with placebo.

A LREE-, Si-, S-enriched fluorapatite with ∼7.7 wt.% LREE 2O3, 5.3 wt.% SiO2 and 3.5 wt.% SO3 from the Mushugai-Khuduk REE deposit, southern Mongolia, has been experimentally metasomatized in pure H2O at 900°C and 1000 MPa. Despite the high LREE content, inclusions or rim grains of monazite did not form during fluid-induced metasomatism. Under high-contrast BSE imaging, the reacted fluorapatite presents a mottled appearance with light, moderate and dark areas and hosts large fluid inclusions containing anhydrite as the solid phase. Dark areas show moderate depletion in all the LREE. Measurable HREE such as Gd and Y remain unchanged. In the areas of intermediate brightness, Ce and, to a lesser extent, La are moderately enriched relative to the original fluorapatite. In the light areas, Ce and La display strong enrichment, whereas the other LREE, Gd and Y remain little changed. In the dark areas, depletion in LREE is matched by depletion in Si and Na, satisfying the coupled substitution reactions Si4+; + (LREE)3+ = P5+ + Ca2+ and Na+ + (LREE)3+ = 2Ca2+. In the light areas, enrichment in LREE and P is accompanied by depletion in Si, Na and S, implying operation of two different coupled substitution reactions, namely: 2P5+ = Si4+ + S6+ and 2P5+ + LREE3+ = 2S6+ + Na+. In all areas, strong enrichment in F is accompanied by strong depletion in Cl and OH. The formation of large, fluid and anhydrite-filled inclusions associated with the LREE-enriched light areas is evidence of a negative volume change, combined with additional local dissolution of the fluorapatite. This occurred during the metasomatism of the original Cl- and OH-bearing fluorapatite to a nearly pure end-member fluorapatite. Local dissolution of fluorapatite in the space now occupied by the voids, combined with element remobilization from the body of the fluorapatite as a whole, provided the Ca and S needed for the formation of anhydrite as well as the P and LREE required for the enrichment of the bright areas.

To material scientists the term texture means the crystallographic orientation of grains in a polycrystal. In contrast, geologists use the term more generally to refer to the spatial arrangement or association of mineral grains in a rock. In this contribution we are concerned with the materials science definition. There are several established techniques available for the determination of crystallographic textures in rocks. It has also been realised that the scanning electron microscope (SEM) is applicable to the study of crystallographic textures via the electron channelling (EC) effect. This provides an image of mineral/rock microstructure (via orientation contrast), as well as a means of accurately indexing their crystal orientations (via electron channelling patterns, ECP). Both types of EC image result from the relationship between incident electron beam and crystal structure, and the subsequent modulation of the backscattered electron (BSE) emission signal according to Bragg's Law. It is a simple matter to switch between the two imaging modes. A related effect, electron backscattering, provides only the diffraction patterns, but has superior spatial resolution and pattern angles.

Due to crystal symmetry restrictions, there is only a limited range of ECP configurations possible for any mineral. Individual patterns can therefore be identified by comparison with the complete ‘ECP-map’. The location of an individual pattern within the map area is determined by spherical angles, the exact definition of which depends on the type of fabric diagram (e.g. inverse pole figure, pole figure or orientation distribution function). Originally, these angles were measured manually. A computer program (CHANNEL) has been developed which uses a digitisation approach to pattern recognition, derives the required fabric diagrams and also constructs ECP-maps from standard crystal data (i.e. unit cell parameters etc.).

The combination of SEM/EC and CHANNEL dramatically facilitates the study of crystal textures in minerals and rocks, making statistical crystallographic analysis from individual orientations a practicality. The following example applications are considered: (1) crystal structure representation of the Al2SiO5 polymorph system; (2) local crystal texture relationships (epitaxial nucleation) between andalusite and sillimanite grains; (3) bulk rock crystal textures of quartzites; and (4) physical properties (e.g. elastic constants and seismic velocities) determined from bulk rock texture.

Excavations at several locations in Verteba Cave have uncovered a large amount of human skeletal remains in association with faunal bones and Tripolye material culture. We aim to establish radiocarbon (14C) dates for eight sites and to evaluate whether these deposits are singular events, or slow accumulations over time. 14C measurements, along with stable carbon and nitrogen isotope data from human and faunal remains, were collected from 18 specimens. Stable isotope values were used to evaluate human and animal diet, and whether freshwater reservoir effects offset measured dates. We found diets of the sampled species had limited to no influence from freshwater resources. Human diet appears to be dominated by terrestrial plants and herbivores. Four new sites were identified as Eneolithic. Comparisons of dates from top and bottom strata for two sites (7 and 20) reveal coeval dates, and we suggest that these deposits represent discrete events rather than slow continuous use. Lastly, we identified dates from the Mesolithic (8490±45 BP, 8765±30 BP), Iron Age (2505±20 BP), Slavic state era (1315±25 BP), and Medieval Period (585±15 BP), demonstrating periodic use of the cave by humans prior to and after the Eneolithic.

The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.

Inertial Measurement Systems (IMS) allow the position calculation of moving objects without requiring outside information. For years the inertial 3-D coordinate measuring technique has been subject to intense research in geodesy and autonomous navigation of land-, water-and airborne vehicles. Because of these areas of application inertially-based systems have been designed for long term measuring only. Here we discuss the requirements that are imposed on inertial sensors in order for them to be used for the calculation of positions of robots. The use of modern sensor technology, combined with strategies for error correction, can result in substantial advantages when calculating robot positions independently from load and environment.

Targets have been developed to measure supersonic radiation transport in aerogel foams using absorption spectroscopy. The target consists of an aerogel foam uniformly doped with either titanium or scandium inserted into an undoped aerogel foam package. This creates a localized doped foam region to provide spatial resolution for the measurement. Development and characterization of the foams is a key challenge in addition to machining and assembling the two foams so they mate without gaps. The foam package is inserted into a beryllium sleeve and mounted on a gold hohlraum. The target is mounted to a holder created using additive manufacturing and mounted on a stalk. The manufacturing of the components, along with assembly and metrology of the target are described here.

A new generation of solar instruments provides improved spectral, spatial, and temporal resolution, thus facilitating a better understanding of dynamic processes on the Sun. High-resolution observations often reveal multiple-component spectral line profiles, e.g., in the near-infrared He i 10830 Å triplet, which provides information about the chromospheric velocity and magnetic fine structure. We observed an emerging flux region, including two small pores and an arch filament system, on 2015 April 17 with the ‘very fast spectroscopic mode’ of the GREGOR Infrared Spectrograph (GRIS) situated at the 1.5-meter GREGOR solar telescope at Observatorio del Teide, Tenerife, Spain. We discuss this method of obtaining fast (one per minute) spectral scans of the solar surface and its potential to follow dynamic processes on the Sun. We demonstrate the performance of the ‘very fast spectroscopic mode’ by tracking chromospheric high-velocity features in the arch filament system.

Waterborne illness related to the consumption of contaminated or inadequately treated water is a global public health concern. Although the magnitude of drinking water-related illnesses in developed countries is lower than that observed in developing regions of the world, drinking water is still responsible for a proportion of all cases of acute gastrointestinal illness (AGI) in Canada. The estimated burden of endemic AGI in Canada is 20·5 million cases annually – this estimate accounts for under-reporting and under-diagnosis. About 4 million of these cases are domestically acquired and foodborne, yet the proportion of waterborne cases is unknown. There is evidence that individuals served by private systems and small community systems may be more at risk of waterborne illness than those served by municipal drinking water systems in Canada. However, little is known regarding the contribution of these systems to the overall drinking water-related AGI burden in Canada. Private water supplies serve an estimated 12% of the Canadian population, or ~4·1 million people. An estimated 1·4 million (4·1%) people in Canada are served by small groundwater (2·6%) and surface water (1·5%) supplies. The objective of this research is to estimate the number of AGI cases attributable to water consumption from these supplies in Canada using a quantitative microbial risk assessment (QMRA) approach. This provides a framework for others to develop burden of waterborne illness estimates for small water supplies. A multi-pathogen QMRA of Giardia, Cryptosporidium, Campylobacter, E. coli O157 and norovirus, chosen as index waterborne pathogens, for various source water and treatment combinations was performed. It is estimated that 103 230 AGI cases per year are due to the presence of these five pathogens in drinking water from private and small community water systems in Canada. In addition to providing a mechanism to assess the potential burden of AGI attributed to small systems and private well water in Canada, this research supports the use of QMRA as an effective source attribution tool when there is a lack of randomized controlled trial data to evaluate the public health risk of an exposure source. QMRA is also a powerful tool for identifying existing knowledge gaps on the national scale to inform future surveillance and research efforts.