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Soil organic matter (SOM) as a solid or as a film at mineral surfaces affects wetting properties in unsaturated soil. Soil organic matter mostly consists of a heterogeneous mixture of components with hydrophilic and hydrophobic functional groups. This paper analyzes relations of SOM to soil wettability by considering functional group compositions of different soluble fractions. Forest soil samples from two loamy sand Cambisol profiles (locations Chorin and Steigerwald) and from a Podzol (Waldstein) were used to obtain water SOM(W) and sodium pyrophosphate SOM(PY) soluble SOM fractions. The hydrophobic (A) and hydrophilic (B) functional groups of bulk soil SOM and of the soluble fractions were evaluated using transmission Fourier-transform infrared (FT-IR) spectroscopy. Advancing liquid-solid contact angles (CA) were determined by using the capillary rise method. For soil organic carbon (SOC) contents <10 g kg(-1), wettability increased with SOC content while it decreased for SOC contents >10 g kg(-1). Although hydrophilic groups in FT-IR spectra of SOM(W), SOM(PY), and bulk soil dominated (i.e., A/B ratios between 0.08 and 0.5), soil wettability was reduced (i.e., CA between 88 and 52 degrees). Soil specific relations between CA and A/B ratios could be obtained after introducing relatively soil type independent factors, G. As exponential functions of the SOC/clay relation, the G-factors imitate the effectiveness of functional groups with respect to wettability. The results suggest that in addition to SOC content, the SOM composition may improve explanations of soil wettability if the spatial orientation of SOM functional groups at the SOM-mineral surface in the presence of sorption sites and polyvalent cations is considered.

In view of the discovery of a new boson by the ATLAS and CMS Collaborations at the LHC, we present an update of the global Standard Model (SM) fit to electroweak precision data. Assuming the new particle to be the SM Higgs boson, all fundamental parameters of the SM are known allowing, for the first time, to overconstrain the SM at the electroweak scale and assert its validity. Including the effects of radiative corrections and the experimental and theoretical uncertainties, the global fit exhibits a p -value of 0.07. The mass measurements by ATLAS and CMS agree within 1.3 σ with the indirect determination . Within the SM the W boson mass and the effective weak mixing angle can be accurately predicted to be M W =80.359±0.011 GeV and from the global fit. These results are compatible with, and exceed in precision, the direct measurements. For the indirect determination of the top quark mass we find , in agreement with the kinematic and cross-section-based measurements.

As top predators, leopard seals ( Hydrurga leptonyx ) have a key role in Southern Ocean ecosystems. For example, this species has driven the local collapse of Antarctic fur seals ( Arctocephalus gazella) at Cape Shirreff, in the northern Antarctic Peninsula. However, little is known about leopard seal haul out site fidelity and social behavior. Here, we employ “genomic tagging” and relatedness analyses from a genome-wide single nucleotide polymorphism (SNP) dataset obtained from 88 leopard seal tissue samples to investigate patterns of seasonal haul out site fidelity and social structure at Cape Shirreff, a leopard seal hotspot during austral summers. Although many seals were observed only once, some females had remarkably high site fidelity returning to the same location across timeframes of up to eight years. Most leopard seals were unrelated, but we identified a trio of closely related females, including a mother-daughter pair, indicating that seasonal site fidelity can span generations. Interestingly, the mother leopard seal identified through our relatedness analyses is a foraging specialist that targets Antarctic fur seal pups; her diet changed very little over the past decade. Our findings suggest high individual variability in leopard seal behavior regarding site fidelity and social structure. Such flexibility may play a key role in this species’ responses to environmental change.

We present an update of the Standard Model fit to electroweak precision data. We include newest experimental results on the top-quark mass, the W mass and width, and the Higgs-boson mass bounds from LEP, Tevatron and the LHC. We also include a new determination of the electromagnetic coupling strength at the Z pole. We find for the Higgs-boson mass and when not including and including the direct Higgs searches, respectively. From the latter fit we indirectly determine the W mass to be . We exploit the data to determine experimental constraints on the oblique vacuum polarisation parameters, and confront these with predictions from the Standard Model (SM) and selected SM extensions. By fitting the oblique parameters to the electroweak data we derive allowed regions in the BSM parameter spaces. We revisit and consistently update these constraints for a fourth fermion generation, two Higgs doublet, inert Higgs and littlest Higgs models, models with large, universal or warped extra dimensions and technicolour. In most of the models studied a heavy Higgs boson can be made compatible with the electroweak precision data.

Plants signal their health in a broader spectrum than we can see with our eyes. We compared sunlight reflectance on plants at spectral wavelengths ranging from 430 nm to 870 nm in our study. These are based on multispectral images captured at a distance of 2 m. Indoor plants were observed over a period of 18 days and stressed due to a lack of sunlight or water. Wild sedge photographed on the forest floor at close range and with a difficult capture setup produced results comparable to published multispectral signatures derived from aerial imagery. Changes of leaf reflectance were noticed in spectral signatures and in vegetation indices. When calculating vegetation indices, our results show that comparing red and red edge reflectance values is superior to comparing red and NIR reflectance values.

Multiple sclerosis is a heterogeneous disease with varying clinical picture. There have been substantial efforts to develop outcome measurements for therapeutic interventions but very few studies have addressed the value of bodily functions from the patient perspective. In a randomly selected cohort of early (<5 years, n = 84) and longer lasting disease courses (>15 years, n = 82) patients we asked for a weighting of 13 bodily functions and compared results with actual disability as measured by the United Kingdom Disability Scale. Lower limb function was given the highest priority in both patient groups followed by visual functioning and cognition especially in longer lasting MS. Actual disability did not correlate with the given priorities indicating that experienced deficits do not influence the subjective ratings of bodily functions. These results underline that ambulation-focused scales in MS represent a key dimension from the patient perspective. Visual functioning should be taken more into account.

Motivated by the availability of 20,000 line‐km of airborne electromagnetic (AEM) data covering the Central Valley of California, we developed a workflow that uses resistivity profiles from electromagnetic (EM) data to assess the suitability of areas for groundwater recharge. We defined a suitable area as one where “fastpaths” of coarse‐grained material could efficiently move water from the ground surface to the water table. We defined recharge metrics and generated the corresponding maps by integrating resistivity profiles from AEM data, sediment type (from driller's logs), water level measurements, and water quality measurements. The workflow is publicly available through a web‐based application, fastpath (https://fastpath.stanford.edu). We produced maps displaying recharge metrics on a 400 m × 400 m grid covering the Central Valley, with 80% of the cells sufficiently close to an AEM resistivity profile (within ∼3 km) to be assessed for recharge. Various decisions are made in the workflow that result in a range of values for determined metrics at any given location. The maps summarizing all metrics show that between 19% (2,000,000 acres) and 56% (7,000,000 acres) of the total area in the valley is land suitable for recharge. The landcover with the largest total area of land classified as suitable is cultivated crops. We estimated the total space available for recharge water to be ∼170 km3 which is two orders of magnitude greater than an estimate of the total volume of water likely to be available for recharge. Plain Language Summary The changing climate in California is raising concerns about sustaining the supply of groundwater. One proposed solution is to use excess water during years of flooding to recharge or replenish the groundwater systems. At a site that is suitable to use for recharge, water can be spread on the ground surface and will efficiently move downward through connected pathways of sand and gravel to reach the water table. We have available in the Central Valley of California 20,000 km of geophysical data, acquired using a helicopter, that images sediment type between the ground surface and the water table. We developed a workflow that allowed us to analyze these geophysical data and produce maps of the Central Valley displaying recharge metrics, measures of the suitability of an area for recharge. The maps summarizing all metrics show that between 19% (2,000,000 acres) and 56% (7,000,000 acres) of the total area in the valley is land suitable for recharge. The landcover with the largest total area of land classified as suitable is cultivated crops. We estimated the total space available for recharge water to be ∼170 km3 which is two orders of magnitude greater than an estimate of the total volume of water likely to be available for recharge. Key Points Developed a workflow to assess areas for groundwater recharge using electromagnetic data to generate maps displaying metrics Recharge metric maps of the Central Valley, using airborne electromagnetic data, classify 19%–56% of the land suitable for recharge The landcover with the largest total area of land classified as suitable for recharge is cultivated crops

Throughout most of the twentieth century, electric propulsion was considered the technology of the future. Now, the future has arrived. This important new book explains the fundamentals of electric propulsion for spacecraft and describes in detail the physics and characteristics of the two major electric thrusters in use today, ion and Hall thrusters. The authors provide an introduction to plasma physics in order to allow readers to understand the models and derivations used in determining electric thruster performance. They then go on to present detailed explanations of: Thruster principles Ion thruster plasma generators and accelerator grids Hollow cathodes Hall thrusters Ion and Hall thruster plumes Flight ion and Hall thrusters Based largely on research and development performed at the Jet Propulsion Laboratory (JPL) and complemented with scores of tables, figures, homework problems, and references, Fundamentals of Electric Propulsion: Ion and Hall Thrusters is an indispensable textbook for advanced undergraduate and graduate students who are preparing to enter the aerospace industry. It also serves as an equally valuable resource for professional engineers already at work in the field.

A 3D model can be useful for inventory management and monitoring of forests. For this task, we present our prototype mobile mapping backpack system for collecting 3D point clouds of forest vegetation. However, data collection in forests is challenging due to unreliable GNSS positioning, moving objects caused by winds, unclear object edges, and uneven ground to walk on. We include LiDAR and IMU with Simultaneous Localisation and Mapping (SLAM). We describe in detail our backpack system, its development for the forest environment, and evaluate it. Furthermore, we compare two open code SLAM algorithms for ROS, as well as data collection and laser scan quality between TLS and MLS for forest environments. Finally, we installed and tested the MicaSense multi-spectral camera on our backpack and discuss the advantages and drawbacks of it. We conclude, that the backpack is convenient to use in forest environments and produces a good point cloud. It can be carried easily off trail and on rough terrain. The system needs less storage space, computation and less collection time than TLS.