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Using a suite of Observing System Simulation Experiments (OSSEs), the utility of simulated Surface Water Ocean Topography (SWOT) observations is estimated in a high-resolution (1 km) ocean analysis/forecasting system. Sampling a Nature Run provides observations for the OSSEs and the realism of the Nature Run is established by comparison to climatological data and an independent ocean analysis/forecast system. Each OSSE experiment assimilated different sets of simulated observations including traditional nadir altimeters, satellite sea surface temperature (SST), in situ profile data, and SWOT. OSSE evaluation metrics include area-averaged errors and wavenumber spectra with the latter providing much finer differentiation between experiments. 100 m temperature, sea surface height (SSH), and mixed layer depth (MLD) errors across the observed wavenumber spectra were reduced by up to 20% for OSSEs assimilating the simulated SWOT observations. The minimum constrained wavelength was found to be 130 km when both nadir altimetry and SWOT observations were used. The experiment using only nadir altimetry produced a value of 161 km. This 31 km gain in skill of predictable scales suggests that ocean forecasts can expect substantial gains in capability when utilizing the forthcoming SWOT data. Experimentation with the analysis decorrelation length scale suggests that emerging multi-scale assimilation methodologies will provide additional advancements in predictive skill.

To assist medical and hearing-science professionals in supporting parents of deaf children, we have identified common questions that parents may have and provide evidence-based answers. In doing so, a compassionate and positive narrative about deafness and deaf children is offered, one that relies on recent research evidence regarding the critical nature of early exposure to a fully accessible visual language, which in the United States is American Sign Language (ASL). This evidence includes the role of sign language in language acquisition, cognitive development, and literacy. In order for parents to provide a nurturing and anxiety-free environment for early childhood development, signing at home is important even if their child also has the additional nurturing and care of a signing community. It is not just the early years of a child's life that matter for language acquisition; it's the early months, the early weeks, even the early days. Deaf children cannot wait for accessible language input. The whole family must learn simultaneously as the deaf child learns. Even moderate fluency on the part of the family benefits the child enormously. And learning the sign language together can be one of the strongest bonding experiences that the family and deaf child have.

The Conditional Affinity Spectrum (CAS) is essential for describing the binding site heterogeneity of natural organic matter. A numerical method called ‘Fully Optimized ContinUouS’ (FOCUS) is described and employed to determine the CAS of H and Pb binding to Suwannee River Humic Acid (SRHA). The FOCUS-CAS is compared with the analytical solution of CAS based on the fitting of the experimental data to the Non-Ideal Competitive Adsorption (NICA) model. Although both methods give satisfactory results, their CAS distribution features are different, indicating that different CAS can reproduce the binding data at similar level of goodness-of-fit. Within a comparable, but not identical, affinity range, the FOCUS-CAS shows multimodal distributions, whereas the NICA-CAS displays bimodal distributions. These differences are due to the fact that the NICA-CAS assumes an a priori functionality (i.e., carboxylic and phenolic), while the FOCUS-CAS does not make this assumption. Without knowing the chemical reality of the binding site explicitly, both methods are viable. The NICA-CAS is theoretically superior to the FOCUS-CAS because it provides informative descriptions of competition between the H- and Pb-binding. Nonetheless, the FOCUS-CAS is practically more convenient because it does not require proton binding data. Additionally, the FOCUS-CAS can describe some strong metal-binding sites (e.g., thiol) that cannot be described by the NICA-CAS and, thus, constitutes a suitable alternative to NICA-CAS.

Lyft Line and UberPool offer travelers lower prices than personal ride-hailing service in exchange for the ability of drivers to serve other passengers during the ride. The rising popularity of these ridesplitting services raises questions about the potential diversion of traffic from urban transit services. To help answer those questions, this study explores travel time and fare differences between UberPool and traditional transit service on 50 paired trips, between 3 and 11 miles long, in Chicago, Illinois. UberPool is found to reduce trip times by an average of 67.6% between neighborhoods, compared to just 13.7% to and from the central business district. Multiple regression analysis shows travel times on CTA and UberPool are similar for trips in which transit riders do not need to make transfers or walk long distances. Consumers save $1.29/minute when using UberPool on trips originating or terminating in the downtown district, compared to just $.38/minute on trips between neighborhoods. In both cases, the amount spent per minute saved exceeds the level the U.S. Department of Transportation recommends using when conducting analysis about the value transit users place on saving time.

In atomic nuclei, the spin-orbit interaction originates from the coupling of the orbital motion of a nucleon with its intrinsic spin. Recent experimental and theoretical works have suggested a weakening of the spin-orbit interaction in neutron-rich nuclei far from stability. To study this phenomenon, we have investigated the spin-orbit energy splittings of single-hole and single-particle valence neutron orbits of 132Sn. The spectroscopic strength of single-hole states in 131Sn was determined from the measured differential cross sections of the tritons from the neutron-removing 132Sn(d, t)131Sn reaction, which was studied in inverse kinematics at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. The spectroscopic factors of the lowest 3/2+, 1/2+ and 5/2+ states were found to be consistent with their maximal values of (2j+1), confirming the robust N=82 shell closure at 132Sn. We compared the spin-orbit splitting of neutron single-hole states in 131Sn to those of single-particle states in 133Sn determined in a recent measurement of the 132Sn(d, p)133Sn reaction. We found a significant reduction of the energy splitting of the weakly bound 3p orbits compared to the well-bound 2d orbits, and that all the observed energy splittings can be reproduced remarkably well by calculations using a one-body spin-orbit interaction and a Woods–Saxon potential of standard radius and diffuseness. The observed reduction of spin-orbit splitting can be explained by the extended radial wavefunctions of the weakly bound orbits, without invoking a weakening of the spin-orbit strength. Keywords: Nuclear structure, Spin-orbit interaction, Transfer reactions, Doubly-magic nuclei, Shell model

Nickel (Ni) emissions resulting from production and transportation raise concerns about the impact of Ni exposure to marine ecosystems. Ni bioavailability models are established for FW systems, but the influence of chemical parameters (e.g. dissolved organic carbon (DOC)) on Ni toxicity within marine systems is less well understood. To examine the effects of DOC concentration and composition on Ni toxicity, acute toxicity tests were conducted on early life-stages of blue mussels (Mytilus edulis) and sea urchin embryos (Strongylocentrotus purpuratus) in full strength sea water (32 ppt). Nine different field collected samples of water with varying concentration (up to 4.5 mg C/L) and composition of DOC were collected from the east coast of the United States. Organic matter compositional analysis included molecular fluorescence and absorbance spectroscopy. The different DOC sources had different protective effects against embryo toxicity. The control (no DOC) Ni 48 h-EC50 for Mytilus embryos was 133 µg/L (95% confidence interval (C.I.) of 123–144 µg/L), while Strongylocentrotus embryos displayed control 96-h EC50 values of 207 µg/L (167–247 µg/L). The most significantly protective sample had high humic acid concentrations (as determined from fluorescence spectroscopy), which yielded an EC50 of 195 µg/L (169–222 µg/L) for Mytilus, and an EC50 of 394 µg/L (369–419 µg/L) for S. purpuratus. Among all samples, protection was related to both DOC quantity and quality, with fluorescence-resolved humic and fulvic acid concentrations showing the strongest correlations with protection for both species. These data suggest that DOC is protective against Ni toxicity in M. edulis and S. purpuratus, and that accounting for a DOC quality factor will improve predictive toxicity models such as the biotic ligand model.

Direct measurements of ( α , p ) reactions of astrophysical interest with radioactive beams presents serious challenges because of the difficult nature of helium targets and the typical low intensities of the beams. To address this, a new technique has been developed for measurements of low-energy ( α , p ) reactions with heavy ion beams using an extended 4 He gas target and a newly developed gas recirculating system. The system was used to measure the 4 He(19F, 1 H)22Ne reaction as a demonstration. Excitation functions of the 19F( α , p )22Ne and 19F( α , p ′ )22Ne ∗ reactions were successfully measured to show the viability of this technique. Details of the approach and future plans are given.

To better understand the effects of interprofessional training on clinical and systems outcomes, there is a need for cross-professional, competency-based assessment instruments that yield scores from which one can make valid inferences. Existing instruments have not been developed across medicine, nursing, pharmacy, and psychology for both pre- and post-licensure trainees. This paper describes our efforts to: 1) provide a crosswalk of the competency documents for these four professions, 2) create an Interprofessional Clinic Assessment Tool , focused on engagement with the team and assigned patient panel, and 3) generate initial validation evidence. Preliminary outcome data indicates the Interprofessional Clinic Assessment Tool (IP-CAT) is efficient and effective in evaluating interprofessional competencies and facilitating improved interprofessional communication/discussion. Future studies should focus on determining effectiveness in a variety of training settings.

A recoil mass separator SECAR has been designed for the purpose of studying low-energy ( p , γ ) and ( α , γ ) reactions in inverse kinematics with radioactive beams for masses up to about A = 65. Their reaction rates are of importance for our understanding of the energy production and nucleosynthesis during explosive hydrogen and helium burning. The radiative capture reactions take place in a windowless hydrogen or He gas target at the entrance of the separator, which consists of four Sections . The first Section selects the charge state of the recoils. The second and third Sections contain Wien Filters providing high mass resolving power to separate efficiently the intense beam from the few reaction products. In the following fourth Section , the reaction products are guided into a detector system capable of position, angle and time-of-flight measurements. In order to accept the complete kinematic cone of recoil particles including multiple scattering in the target in the center of mass energy range of 0.2 MeV to 3.0 MeV, the system must have a large polar angle acceptance of ± 25 mrad. This requires a careful minimization of higher order aberrations. The present system will be installed at the NSCL ReA3 accelerator and will be used with the much higher beam intensities of the FRIB facility when it becomes available.

The adsorption of the C2 hydrocarbons, including ethane, ethene, and ethyne, are studied on magnetite Fe3O4(001) by a combination of molecular beam dosing, temperature programmed desorption, and X-ray photoelectron spectroscopy. The ethane desorption profile has a single temperature invariant peak at 100 K, while ethene and ethyne exhibit additional peaks at ∼120 -and ∼135 K. An inversion analysis is used to extract coverage-dependent desorption energies as well as coverage-averaged prefactors for each molecule. Ethene and ethyne exhibit moderate coverage-dependent desorption energies decreasing from ∼80 to ∼30 kJ/mol at saturation, while ethane shows a relatively coverage invariant desorption energy ∼28 kJ/mol. The desorption energies of the C2 hydrocarbons increase in the order of increasing bond order. This is likely due to the enhanced interaction of the ethene and ethyne π system to the coordinatively unsaturated octahedral Fe sites (Feoct) on the oxide surface. The saturation coverages of each C2 hydrocarbon at 82 K were also determined. These match well with the 2-dimensional area determined from their liquid densities.

This study explores factors contributing to the uneven success of past expansions of dock-based public bikesharing systems, in which middle- and - higher-income neighborhoods have tended to benefit considerably more than poorer neighborhoods. After a review of the differing performance of the three phases of expansion by Chicago's Divvy bikeshare system, this study uses multivariate adaptive regression splining (MARS) to select among more than 100 community- and station-level factors to explain variations in Divvy system usage at the station level. MARS demonstrates that neighborhood racial and ethnic diversity, proportion of condominium units, and job accessibility to public transit are strongly and positively correlated with total annual station trips, whereas percentage unemployed, average distance to Divvy stations, and percentage of residential foreclosures are negatively correlated. Model results are compared with those of earlier studies to foster insights into ways to more accurately predict the use of bikesharing systems across urban neighborhoods.

Light energy and oxygen drive photo-oxidation of dissolved organic carbon (DOC). The longer the wavelength the greater its depth of penetration into water, changing the spectral environment with depth. We asked how oxygen concentration and light spectral composition might affect photo-oxidation processes in DOC. Outdoor experiments compared responses of fluorescence and absorbance indices to photo-oxidation of filtered (0.45 µm) Rio Negro water (Amazon Basin) under near-anoxia, normoxia and hyperoxia exposed to natural sunlight or reduced sunlight (≥340, reduced-UVR). Near-anoxia decreased all absorbance and fluorescence indices. Absorbance changed across the spectrum (≥250 nm) even under reduced-UVR provided that oxygen was present. This phenomenon maintains broader photo-oxidation and the release of CO2 at depth. Slope350–400 was responsive to changes in the irradiance field but not to oxygen concentration, while Slope275–295 responded to both. Thus, larger molecules are broken down near the water's surface and medium to smaller molecules continue to be processed at depth. The production of fulvic acid-like fluorescence required both UVB and oxygen, restricting its production to surface waters. The relatively small increase in R254/365 compared with the loss of SUVA254 under near-anoxia indicated a slower breakdown of larger DOC molecules as oxygen becomes limiting. Breakdown of larger molecules which absorb in the 350–400 nm range, appears to involve two steps – one by radiant energy and another involving oxygen. The study results reflect the dynamic gradients in photo-oxidation with depth.

A Fast Integrated Mobility Spectrometer (FIMS) with a wide dynamic size range has been developed for rapid aerosol size distribution measurements. The design and model evaluation of the FIMS are presented in the preceding paper (Paper I, Wang et al., 2017 ), and this paper focuses on the experimental characterization of the FIMS. Monodisperse aerosol with diameter ranging from 8 to 600 nm was generated using a Differential Mobility Analyzer (DMA), and was measured by the FIMS in parallel with a Condensation Particle Counter (CPC). The mean particle diameter measured by the FIMS is in good agreement with the DMA centroid diameter. Comparison of the particle concentrations measured by the FIMS and CPC indicates the FIMS detection efficiency is essentially 100% for particles with diameters of 8 nm or larger. For particles smaller than 20 nm or larger than 200 nm, FIMS transfer function and mobility resolution can be well represented by the calculated ones based on simulated particle trajectories in the FIMS. For particles between 20 and 200 nm, the FIMS transfer function is boarder than the calculated, likely due to non-ideality of the electric field, including edge effects near the end of the electrode, which are not represented by the 2-D electric field used to simulate particle trajectories.

We evaluated the effects of varying water chemistry ([Ca2+]=0.2-3mM, [Mg2+]=0.05-3mM, dissolved organic matter (DOM, natural, from maple leaves)=0.3-10mg of CL-1, pH=5.0-8.5) on the acute (96-h, unfed fish) and chronic (30-d, fed fish) toxicity of waterborne Cu to juvenile rainbow trout (Oncorhynchus mykiss) exposed in flow-through conditions. Acute and chronic Biotic Ligand Models (BLMs) were developed from the obtained toxicity data-sets, using the Visual MINTEQ software. Our results indicate that Cu is predominantly an acute toxicant to rainbow trout, as there were no observable growth effects and the 96-h and 30-d LC50 values were similar, with mortality mostly occurring within the first few days of exposure. Calcium and DOM were greatly protective against both acute and chronic Cu toxicity, but Mg seemed to only protect against chronic toxicity. Additional protection by pH 5.0 in acute exposure and by pH 8.5 in chronic exposure occurred. In the range of conditions tested, the observed 96-h LC50 and 30-d LC20 values varied by a factor of 39 and 27 respectively. The newly developed acute and chronic BLMs explained these variations reasonably well (i.e. within a 2-fold error), except at pH≥8 where the high observed acute toxicity could not be explained, even by considering an equal contribution of CuOH+ and Cu2+ to the overall Cu toxicity. The 96-h LC50 values of 59% of 90 toxicity tests from 19 independent studies in the literature were reasonably well predicted by the new acute BLM. The LC20 predictions from the new chronic BLM were reasonable for 7 out of 14 toxicity tests from 6 independent chronic studies (with variable exposure durations). The observed deviations from BLM predictions may be due to uncertainties in the water chemistry in these literature studies and/or to differences in fish sensitivity. A residual pH effect was also observed for both the acute and the chronic data-sets, as the ratio of predicted vs. observed LC values generally increased with the pH. Additional mechanistic studies are required to understand the influence of pH, Na, and Mg on Cu toxicity to trout. The present study presents the first experimentally developed chronic Cu BLM for the rainbow trout. To the best of our knowledge, it also presents the first acute Cu BLM that is based on a published data-set for trout. These newly developed BLMs should contribute to improving the risk assessment of Cu to fish in freshwater.

This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21–23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9–10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). The white paper is furthermore informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12–13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. With the developments outlined in this white paper, answers to long standing key questions are well within reach in the coming decade.

Advanced glycation endproducts (AGEs) are formed in cooked meat products via Maillard reactions, which are seen as a contributor to chronic diseases such as diabetes and heart diseases. A number of reports have shown that natural antioxidants such as phenolic acids in grains, herbs, and spices can inhibit their formation. The objective of the study was to determine the inhibitory effects of selected wheat (Jagger, JA), triticale (Spring Triticale, ST; Thundercale, TH), and Rye (RY) bran on AGEs levels in cooked beef patties, as measured by Ne-carboxymethyl lysine (CML) contents. The CML was detected in all the cooked samples, whereas the patties to which RY (42.0% inhibition), ST (27.5% inhibition), and TH (21.4% inhibition) brans were added significantly decreased CML formation. RY and ST, were more abundant in total phenolics content (TPC) and exhibit higher properties as free radical scavengers. Using Pearson's correlation and multiple linear regression analysis, the inhibition of CML in patties was correlated to the water-holding activity (WHC) of the samples, and the radical scavenging activity of the brans as measured by the 2,2-diphenylpicrylhydrazyl (DPPH) assay. These results suggest that addition of bran may be a potential method of decreasing the formation of AGE in cooked patties.

Background/Purpose As interprofessional education in clinical teaching settings continues to develop and workplace learning becomes more ubiquitous, early adopters will need to disseminate training innovations to diverse sites and programs. It is important for these sites to have a framework to understand and organize dissemination. Methods This study evaluated the dissemination process of a case conference across four geographically diverse sites. The dissemination process was evaluated using the RE-AIM framework with a multi-method evaluation that included trainee-level surveys, patient-level data, and semi-structured interviews with faculty members at all sites. Results The conference was disseminated effectively and with similar patient and trainee-level outcomes. Conclusion Suggestions for future dissemination projects include providing basic process and structural guidelines, allowing site-specific flexibly of implementation, providing a process for site-based evaluation (trainee, patient, and system level), and scheduling a check in call to discuss successes and troubleshoot challenges.

GODDESS is a coupling of the charged-particle detection system ORRUBA to the gamma-ray detector array Gammasphere. This coupling has been developed in order to facilitate the high-resolution measurement of direct reactions in normal and inverse kinematics with stable and radioactive beams. GODDESS has been commissioned using a beam of 134 Xe at 10 MeV/A, in a campaign of stable beam measurements. The measurement demonstrates the capabilities of GODDESS under radioactive beam conditions, and provides the first data on the single-neutron states in 135 Xe, including previously unobserved states based on the orbitals above the N=82 shell closure.

The performance of the maximum likelihood expectation maximization method for unfolding neutron energy spectra using deuterated liquid scintillator is evaluated for future utilization with rare isotope beams. High-resolution neutron energy spectra as well as the detector response matrix were measured at the Edwards Accelerator Laboratory at Ohio University. Maximum-likelihood expectation maximization (MLEM) unfolded neutron spectra are compared with spectra from neutron time-of-flight. The effects of the MLEM stopping criteria and spectrum statistics are also investigated.

Copper at high concentrations is an ionoregulatory toxicant in fish and its toxicity is known to be strongly modulated by the water chemistry. The toxicity of Cu to the tropical fish cardinal tetra (Paracheirodon axelrodi) was investigated in waters from two major rivers of the Amazon watershed: the Rio Negro (filtered0.45μm, pH 5.6, DOC=8.4 mgL

Here, the crystallization kinetics of nanoscale amorphous solid water (ASW) films are investigated using temperature-programmed desorption (TPD) and reflection absorption infrared spectroscopy (RAIRS). TPD measurements are used to probe surface crystallization and RAIRS measurements are used to probe bulk crystallization. Isothermal TPD results show that surface crystallization is independent of the film thickness (from 100 to 1000 ML). Conversely, the RAIRS measurements show that the bulk crystallization time increases linearly with increasing film thickness. These results suggest that nucleation and crystallization begin at the ASW/vacuum interface and then the crystallization growth front propagates linearly into the bulk. This mechanism was confirmed by selective placement of an isotopic layer (5% D2O in H2O) at various positions in an ASW (H2O) film. In this case, the closer the isotopic layer was to the vacuum interface, the earlier the isotopic layer crystallized. These experiments provide direct evidence to confirm that ASW crystallization in vacuum proceeds by a “top-down” crystallization mechanism.

Temperature programmed desorption and molecular beam scattering were used to study the adsorption and desorption of small hydrocarbons (n-alkanes, 1-alkenes and 1-alkynes of C1–C4) on rutile TiO2(110). We show that the sticking coefficients for all the hydrocarbons are close to unity (> 0.95) at an adsorption temperature of 60 K. The desorption energies for hydrocarbons of the same chain length increase from n-alkanes to 1-alkenes and to 1-alkynes. This trend is likely a consequence of additional dative bonding of the alkene and alkyne π system to the coordinatively unsaturated Ti5c sites. Similar to previous studies on the adsorption of n-alkanes on metal and metal oxide surfaces, we find that the desorption energies within each group (n-alkanes vs. 1-alkenes vs. 1-alkynes) from Ti5c sites increase linearly with the chain length. The absolute saturation coverages of each hydrocarbon on Ti5c sites were also determined. The saturation coverage of CH4, is found to be ~ 2/3 monolayer (ML). The saturation coverages of C2–C4 hydrocarbons are found nearly independent of the chain length with values of ~ 1/2 ML for n-alkanes and 1-alkenes and 2/3 ML for 1-alkynes. This result is surprising considering their similar sizes.

Agricultural land use disturbs soil microbial communities, which can reduce crop production and impair ecosystem functioning. We investigated the effects of viticulture on the diversity and composition of three soil microbial communities: bacteria, fungi and arbuscular mycorrhizal fungi, by comparing communities in vineyards and nearby unmanaged areas. All three communities were influenced by land use. Bacteria had higher species richness in vineyards whereas arbuscular mycorrhizal fungi had higher richness in unmanaged areas. Differences between vineyards and unmanaged sites in community composition for the three microbial groups were related to both abiotic and biotic factors. In particular, bacterial communities were most sensitive to soil pH, whereas fungal (including AM fungi) communities responded more to changes in plant diversity. Other abiotic factors (cation exchange, temperature and soil texture) were correlated with community compositional changes, regardless of land use. These results indicate that viticulture practices influence key factors controlling soil microbial communities and possibly affect nutrient availability and other services provided by natural soil communities.

This paper tests the robustness of key elements of the Smith and Weiher (2012) countercyclical capital regime. Such tests are now possible given that the recent house price cycle is nearing its end. The recent house price cycle allows for rigorous out-of-sample testing because it encompassed state-level house price cycles of significantly greater magnitude than those observable by Smith and Weiher during the design period of their stress test. The tests of robustness presented herein support the conclusion that the Smith and Weiher countercyclical capital regime should produce capital requirements sufficient to ensure an entity would remain solvent during severe house price cycles. This conclusion is strongly supported by a back-test of the countercyclical framework using Fannie Mae’s historical book of business. If the countercyclical capital requirement had been in place during the run-up to the recent house price bubble, Fannie Mae would have been sufficiently capitalized to withstand losses it sustained in the subsequent housing crisis. This result is particularly noteworthy given that key components of the Smith and Weiher stress test were designed based upon pre-2002 data. Individual examinations of the trend line, trough, and time path components of the Smith and Weiher countercyclical capital regime all indicate that the underlying methodology is stable and robust. We also find that the countercyclical-related patterns in capital requirements will not vary when the stress test is applied to different credit models, but the level of capital required may vary appreciably. This suggests that over-reliance on any one credit model may not be prudent.?

The astrophysical F 18 ( p , α ) O 15 rate determines, in large part, the extent to which the observable radioisotope 18 F is produced in novae. This rate, however, has been extremely uncertain owing to the unknown properties of a strong subthreshold resonance and its possible interference with higher-lying resonances. The new Jet Experiments in Nuclear Structure and Astrophysics (JENSA) gas-jet target has been used for the first time to determine the spin of this important resonance and significantly reduce uncertainties in the F 18 ( p , α ) O 15 rate.

We use an Observing System Simulation Experiment (OSSE) to quantify improvements in ocean state estimation due to the assimilation of simulated Surface Water Ocean Topography (SWOT) observations using a multi-scale 3DVAR approach. The sequential multi-scale assimilation first generates a large-scale analysis and then updates that analysis with smaller scale corrections. Since we use temperature and salinity depth profiles as proxies for sea surface height (SSH) observations, the results are idealized. Skill metrics consistently show that the multi-scale analysis is superior to the single-scale analysis, specifically because it improves small-scale skill without sacrificing skill at larger scales. The analysis skill over a range of spatial scales is determined using wavenumber spectral analysis of 100 m temperature, SSH, and mixed layer depth (MLD). For MLD, the multi-scale assimilation of SWOT data reduces the minimum constrained wavelength from 158 km to 122 km, a 36 km reduction, compared to a single-scale assimilation of the same data. For SSH, the multi-scale approach only reduces constrained scales from 73 km to 72 km, a 1 km reduction. This small increase in skill is caused by the steep wavenumber spectral slope associated with SSH, which suggests that SSH variability is concentrated at long wavelengths. Ultimately, the small-scale update in the multi-scale assimilation has less to correct for SSH. In contrast, MLD has a relatively flat spectral slope. The multi-scale solution can make a more substantial update to the MLD field because it has more small-scale variability. Thus, our results suggest that the magnitude of the skill improvement provided by the multi-scale solution is negatively correlated with the spectral slope of the ocean variable.

Non-reactive phosphorus (nRP) contains condensed phosphates and organic phosphorus (OP) species that are recalcitrant in secondary wastewater treatment and tend to remain in final effluents. To meet ultra-low effluent P discharge limits, persistent nRP must be removed. The objective of this study was to evaluate the use of an advanced oxidation process (AOP) which couples TiO2/UV photolysis with ultrafiltration to oxidize and remove nRP species. Initial tests utilized OP model compounds, adenosine triphosphate (ATP) and aminoethylphosphonate (AEP), in a binary mixture to evaluate AOP treatment and to elucidate possible mechanisms of phosphorus removal. The results were consistent with a model of preferential ATP binding to the TiO2 surface compared to AEP. On UV light exposure, AEP was removed from solution due to the photooxidation of ATP freeing up binding sites for AEP adsorption and subsequent oxidation. Orthophosphate released during AOP treatment was retained on the TiO2 solids. The AOP was applied to three municipal wastewaters and one automotive industry effluent for P removal. In all cases, phosphorus removal was found to occur through filtration, surface complexation and UV oxidation. Total phosphorus removal efficiencies between 90 and 97% were observed for the municipal wastewater effluents and 44% removal was observed in the industrial effluent after treatment using AOP.

Systems rich in terrigenous dissolved organic carbon (DOC), like the Rio Negro, can contribute significant amounts of carbon dioxide back to the atmosphere and support important microbial communities. We investigated photo-oxidation in the Rio Negro: (1) the depth to which light causes complete photo-oxidation to CO2 and changes in DOC structure, (2) the daily rate of change of absorbance indices, (3) the relationship between sub-surface rates of photo-oxidation to CO2 and light exposure, (4) the areal rates of photo-oxidation, and (5) the stability of fluorophore signals. Experiments were run in an outdoor pool of Rio Negro water, under natural sunlight during the dry seasons of 2015 and 2018. In 2018, rates of complete photo-oxidation and changes in absorbance indices decayed exponentially, approaching their asymptotes between 9 and 15 cm depth. In 2015, direct absorbance indices ceased changing at 14 cm depth. Fluorescence of humic acid-like moieties continued to decrease, sometimes to 35–43 cm depth. This indicates that partial photo-oxidation of DOC, and thus interaction with the microbial community, occurs to greater depths than previously expected. Areal rates of CO2 production were 28.8 and 39.3 mg C m−2 d−1 (two experiments, October 2018). Sub-surface (1.1 cm) rates were strongly related to light levels, reaching a maximum of 0.68 mg C l−1 d−1 in September. Complete photo-oxidation ceased below 29.6 mW cm−2 d−1 UV radiation, providing a daily baseline for observable production of CO2. Absorbance indices changed by 9 to 14% d−1 at high light levels, except for R254/365 (4.4% d−1). Fluorophore emission ranges were stable between 2014 and 2018, indicating that emissions can be compared across time and space. This study contributes to better estimates and understanding of photo-oxidation in tropical, black-water rivers, which will be useful for carbon modelling. © 2020 Elsevier B.V.

In this study, sludge generated from chemically enhanced treatment of primary influent was treated to recover the ferric coagulant, which was reused to coagulate fresh primary influent. The treatment process used to recover the ferric coagulant consisted of acidification and mixing of the chemically – enhanced primary sludge, followed by final separation using centrifugation to recover the coagulant. Although, they performed equally well, sulphuric acid was chosen over hydrochloric acid for the maximum recovery of the coagulant occurring at an optimal pH 1.5. A chemical equilibrium model describing iron-SO4-2 and iron-Cl- chemistry at various pH predicted the formation of complexes like jarosite, which reduced the recovery of iron. With fresh ferric chloride, 90% total suspended solids (TSS), 77% total phosphorous (TP), 70% soluble phosphorous (sP), 62% chemical oxygen demand (COD), and 18% total nitrogen (TN) were removed from primary effluent. With the recovered coagulant, there was a decrease in the TSS, COD and TN removal efficiencies and a corresponding approximately 10% increase in their concentration in the primary effluent. A significant increase in phosphorous concentration occurred due to recycling of the coagulant, which was precipitated as struvite at the end of the second cycle. A preliminary operational cost analysis conducted on the recovery process shows the increased cost of acidification can be offset by the reduction in costs of fresh coagulant, dewatering and sludge disposal.

Redox flow batteries (RFB) provide efficient storage of renewable energy facilitating sustainable energy supply. Among various RFB, the vanadium cerium battery is distinguished with large storage potential and without phase transition during the redox reactions. Herein, a two-dimensional model of a slice of the cell in a vanadium cerium redox flow battery is developed for the first time. Electrochemical characterization of both the V(II)/V(III) and Ce(III)/Ce(IV) electrochemical systems in mixed acid media is conducted to obtain the key parameters of the model. The data obtained from the simulations is then validated against the results of real flow battery experiments exhibiting a good agreement. With the perspective of state-of-the-art design in RFB system management for future large-scale systems, state of charge deviation and flow efficiency, are introduced as innovative measures of lifetime and energy density of the battery. The illustrated effect of several parameters involved in the proposed model provides direction toward optimum design of RFB systems.

An array consisting of 12 deuterated organic liquid scintillator detectors for fast-neutron spectroscopy was designed and built at Oak Ridge National Laboratory (ORNL). This versatile array is designed for measurements with low reaction yields, such as those performed with rare isotope beams, as well as at high current DC facilities used for underground nuclear astrophysics research. Because some measurements also offer limited, or no, additional timing information, the ORNL Deuterated Spectroscopic Array (ODeSA) was optimized to utilize spectrum unfolding to extract neutron energy spectra . This array was characterized for n/ γ pulse shape discrimination, light response, resolution, and intrinsic efficiency by using the neutron time-of-flight tunnel at the Edwards Accelerator Laboratory at Ohio University. Results and future plans are discussed.