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While climate change will challenge the future of California’s water resources, groundwater can buffer variability in precipitation and streamflow, if managed sustainably. Enhanced river recharge is an important tool to reach sustainable groundwater management in the California Central Valley (USA). Understanding and predicting recharge rates of river water, either natural river bank infiltration or managed aquifer recharge (MAR) during floods (Flood-MAR) or on agricultural land (Ag-MAR) is essential to evaluate the sustainability of groundwater management plans. Groundwater ages, combined with other isotopic and noble gas evidence, can elucidate surface water-groundwater interactions and support river recharge rates calculations over longer time periods.Our study is focused on the recharge from the Cosumnes River in the California Central Valley. The Cosumnes River forms the boundary between the Sacramento Valley groundwater basin to the north and the San Joaquin Valley groundwater basin to the south. For this study, 28 new samples were collected for the analysis of 3H/3He age, noble gases, and stable isotopes. 25 additional samples from the California Waterboards Groundwater Ambient Monitoring and Assessment (GAMA) Shallow Aquifer Assessment program were included, which were collected and analyzed by the USGS California Water Science Center in 2017.We find that 28% of groundwater in the San Joaquin – Cosumnes groundwater subbasin originated as river water recharge, based on the interpolated mean δ18O (7.7 ‰ ), compared with river water (-9 ‰) and local precipitation recharge (-7 ‰) end-members. River water is a source of modern recharge, resulting in high tritium concentrations close to the Cosumnes River. In contrast, ambient groundwater from local precipitation recharge is predominantly pre-modern or fossil, containing less than 1 pCi/L tritium. Combining groundwater ages with the distance to the river, aquifer thickness, and porosity, estimates of river water recharge rate vary between 0.02 km3/yr and 0.035 km3/yr. These quantitative estimates of river water recharge will constrain the numerical groundwater flow model for this basin and aid groundwater managers in developing sustainability plans to balance groundwater pumping with recharge rates.

Abstract The combination of two-dimensional (2D) materials into heterostructures enables the formation of atomically thin devices with designed properties. To achieve a high-density, bottom-up integration, the growth of these 2D heterostructures via van der Waals epitaxy (vdWE) is an attractive alternative to the currently mostly employed mechanical transfer, which is problematic in terms of scaling and reproducibility. Controlling the location of the nuclei formation remains a key challenge in vdWE. Here, a focused He ion beam is used to deterministically place defects in graphene substrates, which serve as preferential nucleation sites for the growth of insulating, 2D hexagonal boron nitride (h-BN). Therewith a mask-free, selective-area vdWE (SAvdWE) is demonstrated, in which nucleation yield and crystal quality of h-BN are controlled by the ion beam parameters used for defect formation. Moreover, h-BN grown via SAvdWE is shown to exhibit electron tunneling characteristics comparable to those of mechanically transferred layers, thereby lying the foundation for a reliable, high-density array fabrication of 2D heterostructures for device integration via defect engineering in 2D substrates.

In the tropics, crustose calcifying red algae (Corallinophycidae and Peyssonneliales; CCRA) are dominant and important reef builders that serve a suite of ecological functions affecting reef health. However, CCRA taxa have historically been overlooked in floristic and ecological studies because of their high degrees of phenotypic plasticity and morphological convergence that impede reliable identifications based on morphology. This study provides an update of the CCRA diversity of Guam (Mariana Islands) based on a recent DNA barcoding effort. This account of CCRA taxa is compared to (1) the most current species inventories for Guam based on morphological identifications and (2) similar floristic accounts of CCRA from other regions using DNA barcoding. 492 CCRA specimens were collected from Guam for which two markers, COI-5P and psbA, were used for phylogenetic analysis and species delimitation. Phylogenetic relationships were inferred using maximum likelihood. Species richness estimates were obtained through a conservative approach using the Automatic Barcode Gap Discovery method for species delimitation. A total of 154 putative CCRA species were identified, with 106 representatives of the subclass Corallinophycidae and 48 belonging to the order Peyssonneliales. When compared to previous studies based on morphological identification, molecular data suggests that all but one of the CCRA species reported for Guam were incorrectly identified and CCRA species richness is more than six times higher than previously assumed. Species accumulation curves show that CCRA species richness will continue to rise with increased sampling effort and the exploration of new (micro)habitats before reaching a plateau. Guam’s true CCRA richness might eventually exceed the currently reported species richness of all marine red algae for the island. Of the 154 putative species documented in this study, only ten closely match (≥ 98% COI-5P sequence similarity) previously described species, implying that many are probably new species to science. The here-reported CCRA diversity for Guam as a small, remote tropical island in the Western Pacific Ocean is greater than those of well-documented CCRA floras for much larger nearshore ecosystems in Brazil and New Zealand, emphasizing the value of tropical islands as hotspots of marine biodiversity.

Focused beams of helium ions are a powerful tool for high-fidelity machining with spatial precision below 5 nm. Achieving such a high patterning precision over large areas and for different materials in a reproducible manner, however, is not trivial. Here, we introduce the Python toolbox FIB-o-mat for automated pattern creation and optimization, providing full flexibility to accomplish demanding patterning tasks. FIB-o-mat offers high-level pattern creation, enabling high-fidelity large-area patterning and systematic variations in geometry and raster settings. It also offers low-level beam path creation, providing full control over the beam movement and including sophisticated optimization tools. Three applications showcasing the potential of He ion beam nanofabrication for two-dimensional material systems and devices using FIB-o-mat are presented.

Successful recruitment of invertebrate larvae to reef substrates is essential to the health of tropical coral reef ecosystems and to their capacity to recover from disturbances. Crustose calcifying red algae (CCRA) are a species rich group of seaweeds that have been identified as important recruitment substrates for scleractinian corals. Most studies on the settlement preference of coral larvae on CCRA use morphological species identifications that can lead to unreliable species identification and do not allow for examining species-specific interactions between coral larvae and CCRA. Accurate identifications of CCRA species is important for coral reef restoration and management to assess CCRA community composition and to detect CCRA species that are favored as coral recruitment substrates. In this study, DNA sequence analysis, was used to identify CCRA species to (1) investigate the species richness and community composition of CCRA on experimental coral recruitment tiles and (2) assess if the coral Acropora surculosa preferred any of these CCRA species as recruitment substrates. The CCRA community assemblages on the coral recruitment tiles was species-rich, comprising 27 distinct CCRA species of the orders Corallinales and Peyssonneliales which constitute new species records for Guam. Lithophylloideae sp. 1 (Corallinales) was the CCRA species that was significantly favored by coral larvae as a recruitment substrate. Lithophylloideae sp. 1 showed to hold a valuable ecological role for coral larval recruitment preference. Lithophylloideae sp. 1 had the highest benthic cover on the recruitment tiles and contained most A. surculosa recruits. DNA barcoding revealed a high taxonomic diversity of CCRA species on a microhabitat scale and provided detailed insight into the species-specific ecological interactions between CCRA and corals. With a steady decline in coral cover, detailed information on species interactions that drive reef recovery is valuable for the planning of marine management actions and restoration efforts.

Among the hammerhead sharks, scalloped hammerheads (Sphyrna lewini) have undergone the steepest population declines worldwide. Due to their high susceptibility to exploitation, the species is now classified as ‘critically endangered’, the most threatened category listed by the International Union for Conservation of Nature. There is an urgent need for data on the distribution of S. lewini to inform the design and implementation of effective conservation management strategies, and mitigate the risk of global extinction. Environmental DNA (eDNA) is emerging as a powerful method to monitor the geographic distribution, population trends, and habitat usage of rare and endangered species. In comparison to traditional survey methods, eDNA methods offer lower cost, higher detection rates, and are non-invasive. At present, there is no targeted eDNA assay for the detection of S. lewini and existing methods to assess their distribution are either fisheries-dependent, leading to bias, or costly and laborious, leading to impracticality in regions of low or unknown abundance. Here we present an optimised workflow for the detection of S. lewini presence using eDNA methods, and apply these to successfully detect scalloped hammerhead sharks in Guam, of the western Pacific Ocean, where their presence has not been scientifically reported since the 1970s. The detection of S. lewini by eDNA survey methods was achieved from a single-day sampling effort, demonstrating the efficacy of the technique and workflow. If implemented, the eDNA survey methods developed here will enable the rapid generation of information on the distribution of scalloped hammerhead sharks in the western Pacific, and likely globally, and assist in the accurate placement of no-take reserves to best enable the species’ recovery.

Background: Ready to Move (RTM), a university worksite wellness program, was implemented to get employees moving more and sitting less by combining student health coaching and activity trackers (AT’s). Aim: This article provides program specifics and survey data outcomes to facilitate ideas for university faculty, staff and student collaboration. The intent of the article is to provide an example of how academic classes can contribute to employee worksite wellness programming within a university. Methods: Twelve cohorts (2015 - 2017) comprised of 295 university employees received Fitbit Flex ATs and health coaching from students enrolled in a physical activity (PA) behavioral interventions class during a 10-week program. The employees met with their student coach eight times to learn how to use their AT and set movement goals. Employee’s completed self-reported surveys on average PA days and PA confidence pre/post program. Results: Findings revealed RTM significantly impacted employees average number of PA days and their confidence in ability to sustain PA. Employee qualitative comments revealed RTM instilled the importance of utilizing ATs combined with student engagement made the experience enjoyable and effective. Conclusion: RTM’s combination improved employee movement outcomes and provided additional programming ideas for the employee wellness program at a large Midwestern university.

The building industry makes a great effort to reduce energy consumption. The use of nanotechnology is one of the approaches to surpassing the properties of conventional insulation materials. In this work, an industrial cost‐effective method to manufacture highly porous materials with excellent thermal insulation properties is described. The materials are prepared from polystyrene recovered from the building sector and electrospun as nanofiber‐based sheets. Varying electrospinning parameters allow controlling the morphology of the produced materials. The materials are obtained with differences in interfiber and inner‐fiber porosity and morphology. The thermal conductivity of the freestanding and compressed materials is evaluated. Those differences affect the insulation performance: the materials with higher interfiber porosity show better thermal insulation in the freestanding state. An increase of the inner‐fiber porosity leads to better insulation in the compressed samples. Insertion of carbon nanomaterials reduces the effects of the infrared Radiation. Nanofiber‐based insulation materials from the recycled expanded polystyrene (EPS) show thermal conductivity values of 20 to 25 mW/mK (ie, 20% to 30% below the thermal conductivity of the commercial EPS). The effect of integrating polystyrene nanofiber sheets into conventional wall‐building materials is also investigated in terms of thermal insulation. The nanofiber insulation sheets are sandwiched between two pieces of the building materials resulting in a drastic increase of the insulation effect. The materials have a great potential in using, for example, as thermal insulation for the restoration of historic buildings in the narrow central parts of the old towns.