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Since the 1940s, anthropogenic nitrogen (N) inputs have grown to dominate global N cycles, particularly in fluvial systems. Negative impacts of this enrichment on downstream estuaries are well documented. Efforts at N reductions are increasingly successful but evaluating ecosystem response trajectories is difficult because of a lack of knowledge of historic conditions. To document continental-scale coastal food web N-dynamics prior to large increases in human N-loads, we sampled 208 fish from an archival collection, taken from coastal waters across the continental U.S., with a median collection year of 1904. The archival fish were compared with 526 samples collected in 2015 from 126 estuaries also along the U.S. coastline. We used stable isotopes of N (δ15N) and carbon (δ13C) as a proxy for human inputs and organic matter sources. Watershed attributes from 1910 and 2012, census data, fish life histories, and basic estuarine geography were used to develop random forest models that determined which variables were the best predictors of isotope values. State, latitude, and fish trophic level were consistently the most important predictors, while human impacts played a lesser role. When the fish were collected (~1914 vs 2015) was not an important predictor, rather where the fish was collected was the best predictor of N source. The model results illustrate the important role that geography plays in coastal food web dynamics and underscore the importance of offshore N-sources to coastal food webs.While fine particulate matters are decreasing in the Pearl River Delta (PRD) region, the regional ozone (O3) shows an increasing trend that affects human health, leading to an urgent need for scientific understanding of source-receptor relationship between O3 and its precursor emissions given the changing background composition. We advanced and applied an adjoint air quality model to map contributions of individual O3 precursor emission sources [nitrogen oxides (NOx) and volatile organic compound (VOC)] at each location to annual regional O3 concentrations and to identify the possible dominant influential pathways of emission sources to O3 at different spatiotemporal scales. Additionally, we introduced the novel adjoint sensitivity approach to assess the relationship between precursor emissions and O3-induced premature mortality. Adjoint results show that Shenzhen was a major source contributor to regional O3 throughout all seasons, of which 49.4% (3.8%) were from its NOx (VOC) emissions. Local emissions (within PRD) contributed to 83% of the regional O3 whereas only ~54% of the estimated ~4000 regional O3-induced premature mortalities. The discrepancy between these two contributions was because O3-induced mortalities are dependent on not only O3 concentration, but incident rate and population density. We also found that a city with low O3-induced mortalities could have significant emission contributions to health impact in the region since the transport pathways could be through transport of local O3 or through transport of O3 precursors that form regional O3 thereafter. It is therefore necessary to formulate emission control policies from both air quality and public health perspectives, and it is also critical to have better understanding of influential pathways of emission sources to O3.The United States (US) Environmental Protection Agency (EPA)'s SPECIATE database contains speciated particulate matter (PM) and volatile organic compound (VOC) emissions profiles. Emissions profiles from anthropogenic combustion, industry, wildfires, and agricultural sources among others are key inputs for creating chemically-resolved emissions inventories for air quality modeling. While the database and its use for air quality modeling are routinely updated and evaluated, this work sets out to systematically prioritize future improvements and communicate speciation data needs to the research community. We first identify the most prominent profiles (PM and VOC) used in the EPA's 2014 emissions modeling platform based on PM mass and VOC mass and reactivity. this website It is important to note that the on-road profiles were excluded from this analysis since speciation for these profiles is computed internally in the MOVES model. We then investigate these profiles further for quality and to determine whether they were being appropriate source categories. In addition, we conclude that new source emissions testing would be especially beneficial for residential wood combustion, nonroad gasoline exhaust and nonroad diesel equipment.A study was conducted to determine the effect of transportation distance and crating density on meat quality traits during winter. ROSS-308 broilers aged 35 days were divided into 10 treatment groups based on three transportation distances (80, 160, and 240 km) with three crating densities (10, 12, and 15 birds per crate) along with birds slaughtered on farm without crating as a control group. Each treatment was replicated 10 times and placed at various locations in the truck. The birds were transported in plastic crates of 0.91 m×0.55 m×0.30 m at ambient temperature and relative humidity of 3.6-9.5°C and 63.3-78.8%, respectively. The breast meat quality parameters including pH, color, drip loss, shear force, marinade uptake and retention, cooking losses, and yield were determined. The results showed significantly higher pH 15 min post-slaughter (PS), drip loss, lightness, marinade uptake, raw meat cooking yield, and shear force in birds slaughtered on farm without any transportation. The birds transported for 240 km had significantly higher pH at 2 hours (h) PS, marinade retention, and cooking yield. Whereas, pH at 24 h PS, meat redness, yellowness, chroma, and marinated meat cooking yield were significantly higher in all transported treatments compared to the control group. Among different crating densities, the birds transported with 10 birds per crate showed significantly higher meat redness, marinade retention, and cooking yield. The crating density of 15 birds per crate had significantly higher lightness, hue, cooking loss, and shear force. However, no effect of crating density was observed on meat pH, drip loss, and marinade uptake. It can be concluded that an increase in transportation distance and low crating density during winter can negatively affect physical quality of meat with significant improvement in marination and cooking characteristics.