Evaluating Confidence in the Impact of Regulatory Nutrient Reduction on Chesapeake Bay Water Quality

Excess nutrients derived from anthropogenic activity have resulted in the degradation of coastal water quality and an increase in low-oxygen and hypoxic events worldwide. In an effort to curb these impacts and restore water quality in the Chesapeake Bay, a maximum load of nutrients has been established based on a framework of regulatory standards and models. This research aims to evaluate the projected changes in water quality resulting from the implementation of these nutrient reductions by applying the regulatory methodology to two different models that have been previously shown to have similar model skill. Results demonstrate that although the two models differ structurally and produce a different degree of absolute change, they project a similar relative improvement in water quality along the main stem of the Chesapeake Bay and the lower reaches of the tributaries. Furthermore, the models largely agree on the attainment of regulatory water quality standards as a result of nutrient reduction, while also establishing that meeting water quality standards is relatively independent of hydrologic (wet/dry) conditions. By developing a Similarity Index that compares model results across habitat, time, and methodology, this research identifies the locations and causes of greatest uncertainty in modeled projections of water quality. Although there are specific locations and times where the models disagree, overall this research lends support and increased confidence to the appropriateness of the nutrient reduction levels and in the general impact of nutrient reduction on Chesapeake Bay water quality under current environmental conditions

Associated dataset: The competing impacts of climate change and nutrient reductions on dissolved oxygen in Chesapeake Bay

This research uses an estuarine-watershed hydrodynamic–biogeochemical modeling system along with projected mid-21st-century changes in temperature, freshwater flow, and sea level rise to explore the impact climate change may have on future Chesapeake Bay dissolved-oxygen (DO) concentrations and the potential success of nutrient reductions in attaining mandated estuarine water quality improvements

Novel molecularly imprinted impedimetric biosensor based on polypyrrole and decorated graphene oxide for the routine monitoring of Lysozyme

In this work, a novel molecularly imprinted polymer based on polypyrrole (PPy) and decorated graphene oxide (GO@Fe3O4) was developed for the sensitive detection of lysozyme (LYS). The synthesized material (MIPPy/GO@Fe3O4) was electrodeposited with LYS as a template on gold microelectrodes. Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) were used to confirm the adequate preparation of GO@Fe3O4, and the characterization of the resulting microsensors was carried out with the following analytical techniques: electrochemical impedance spectrometry (EIS), FT-IR analysis and scanning electron microscopy (SEM). An equivalent circuit was suggested to quantitatively analyse each component of the sensor system. EIS was also used for the determination of LYS in a wide linear range from 1 to 1 105 pg/mL, presenting good precision (RSD ≈ 10%, n = 5) and low limits of detection and quantification (LOD = 0.009 pg/mL and LOQ = 0.9 pg/mL, respectively). Meanwhile, the microsensor showed a high sensitivity, a good selectivity and reproducibility. The construction process was relatively simple, and provided a rapid and economical method for the routine monitoring of LYS. The microsensor was successfully applied for the detection of this protein in fresh chicken-egg white sample and commercial drug.Campus de Excelencia Internacional Andalucía Tech. Beca FPU18/05371 Proyecto de la Junta de Andalucía UMA18FEDERJA06

Analysis of Alternative Pure-breeding Structures for Sheep in Smallholder and Pastoral Production Circumstances in the Tropics

The key issue in this study was to technically compare, through stochastic simulation, different breeding programmes that vary in the level of interaction between breeders and producers. The breeding structures considered were: (i) a single closed nucleus providing seed-stock to village flocks, (ii) a group of commercial flocks running a co-operative (‘ram circle’) breeding programme with no nucleus, (iii) an interactive two-tier open nucleus breeding scheme, comprising a nucleus and a commercial tier - the best males are used within the nucleus while the remainder migrate to the commercial flocks, with no female migration, and (iv) as scheme iii but with female migration between tiers. For the latter two schemes, 100% of the nucleus animals are distributed over village flocks every 3 years. The nucleus is then replaced by a new batch of selected males and females from the village flocks obtained through ‘interactive cycling screening’, based on ‘picking the best phenotype’ in the commercial flocks. Single trait selection was considered, and based on estimated breeding value, using either best linear unbiased prediction (BLUP) or the individual’s phenotype as a deviation from contemporaries in the same flock, year and season. The results showed that genetic merit increased slightly and inbreeding decreased significantly with increase in nucleus size. For instance, with BLUP selection and trait measurement on both sexes, and first record established at year 2, a nucleus size of 100 dams with 50 dams mated to each sire resulted in genetic merit of 0.118 units and an average inbreeding coefficient of 0.119 while that with 500 dams gave a response of 0.134 with an average inbreeding coefficient of 0.037. Running one closed nucleus had a 6-24% advantage over a ‘ram circle’ in terms of genetic gain. Decreasing the dam to sire ratio was a simple way to avoid inbreeding in breeding schemes of small size, with very little compromise towards genetic gain or even an increase in the longer term. Relative to a two-tier nucleus (scheme i), cyclic screening of commercial animals for use in the nucleus gave an almost optimum genetic response, while the villagers acquired superior breeding stock in return as an incentive to participate in genetic improvement. Participation of farmers offers them a sense of ownership of the breeding programme, and is likely to make it more sustainable in the long-term. This study provides insight into the advantages and disadvantages of designed breeding structures, especially the ‘interactive cyclic’ breeding schemes, which should be useful in deciding breeding programmes to adopt for sheep in developing countries in the tropics. Keywords: Sheep, Breeding Structures, Selection, Tropic

Diversity, equity, and inclusion in engineering education: an exploration of European higher education institutions’ strategic frameworks, resources, and initiatives

Significant efforts have been made to promote gender equality in higher education (HE) in Europe. Examples include the establishment of the Athena Swan Charter in the UK in 2005 and the 2019 launch of the Irène Curie Fellowship scheme by Eindhoven University of Technology. But which initiatives address broader diversity, equity, and inclusion (DEI) challenges in HE? And which are specifically focused on engineering education? This exploratory study aims to improve our understanding of the ways in which a set of European HE Institutions engaged in engineering education address DEI at an organisation level, and how this is communicated within the public domain. The analysis of online data provided by a purposive sample of institutions is guided by the following research questions (RQ): 1. How is DEI addressed and defined in institution-wide strategic frameworks? 2. How many institutions describe having an institution-wide DEI organization? 3. What specific policies around DEI are being developed, and what areas are mentioned, defined, and prioritized? 4. What structures and resources noted as part of their DEI activities are specific to engineering faculties and departments? 5. What engineering-specific DEI initiatives exist that are not available in the public domain or are not written in English? Our sample is composed of the host institutions of the authors of the paper, and represent different European countries: Belgium, Denmark, France, Ireland, Portugal, Switzerland, and the UK. The findings of this exploratory study will be used to inform the design of a large-scale survey to identify DEI practices across the SEFI community

Utility of early circulating tumour DNA dynamics as a surrogate for progression free survival in the BEECH phase I/II trial in metastatic breast cancer

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A 3D unstructured-grid model for Chesapeake Bay: importance of bathymetry

We extend the 3D unstructured-grid model previously developed for the Upper Chesapeake Bay to cover the entire Bay and its adjacent shelf, and assess its skill in simulating saltwater intrusion and the coastal plume. Recently developed techniques, including a flexible vertical grid system and a 2nd-order, monotone and implicit transport solver are critical in successfully capturing the baroclinic responses. Most importantly, good accuracy is achieved through an accurate representation of the underlying bathymetry, without any smoothing. The model in general exhibits a good skill for all hydrodynamic variables: the averaged root-mean-square errors (RMSE‟s) in the Bay are 9 cm for sub-tidal frequency elevation, 17 cm/s for 3D velocity time series, 1.5 PSU and 1.9 PSU for surface and bottom salinity respectively, 1.1 °C and 1.6 °C for surface and bottom temperature respectively. On the shelf, the average RMSE for the surface temperature is 1.4 °C. We highlight, through results from sensitivity tests, the central role played by bathymetry in this estuarine system and the detrimental effects, from a common class of bathymetry smoothers, on volumetric and tracer fluxes as well as key processes such as the channel-shoal contrast in the estuary and plume propagation in the coast. Associated Data is available: https://doi.org/10.21220/V5HK5

Dynamical Mean-Field Theory of Electron-Phonon Interactions in Correlated Systems: Application to Isotope Effects on Electronic Properties

We use a recently developed formalism (combining an adiabatic expansion and dynamical mean-field theory) to obtain expressions for isotope effects on electronic properties in correlated systems. As an example we calculate the isotope effect on electron effective mass for the Holstein model as a function of electron-phonon interaction strength and doping. Our systematic expansion generates diagrams neglected in previous studies, which turn out to give the dominant contributions. The isotope effect is small unless the system is near a lattice instability. We compare this to experiment.Comment: 6 pages, 4 figures; added discussion of isotope effect away from half fillin