How Nutrient Trading Could Help Restore the Chesapeake Bay

The largest estuary in the United States, the Chesapeake Bay is a vital economic, cultural, and ecological resource for the region and the nation. Excess runoff and discharges of nutrients -- particularly nitrogen and phosphorus -- from farms, pavement, wastewater treatment plants (WWTPs), and other sources have placed the bay on the Environmental Protection Agency's (EPA's) List of Impaired Waters. This nutrient pollution is responsible for creating large algal blooms that lead to "dead zones" in the bay (Chesapeake Bay Program, 2009b). Despite decades of restoration efforts, progress has been slow, and the rivers and streams that drain into the Bay remain polluted (Chesapeake Bay Program, 2009b)

How Baywide Nutrient Trading Could Benefit Maryland Farms

Outlines pending legislation to improve the health of the Chesapeake Bay watershed, including a nutrient trading program that allows farms that reduce runoff of nutrients to below target to sell "credits." Estimates costs, credits, and credit revenue

How Baywide Nutrient Trading Could Benefit Pennsylvania Farms

Outlines how legislation to make the Chesapeake Bay watershed healthier, including a program allowing farms that reduce runoff of nutrients to below target to sell "credits," would benefit Pennsylvania farms through cost-sharing funds and new revenues

Metacognition and Self-regulation Influence Academic Performance in Occupational and Physical Therapy Students

An understanding of student learning strategies is an important component of supporting academic success and avoiding difficulty. Prior inquiry has demonstrated certain learning strategies are more closely related to academic performance than others. The purpose of this study was to describe predictive relationships between the Metacognitive Awareness Inventory (MAI), Learning and Study Strategies Inventory (LASSI), and grade point average (GPA) in occupational therapy (OT) and physical therapy (PT) programs. A multi-center convenience sample of N=75(100%) entry-level students [OT: 34(45%); PT: 41(55%)] was included from Florida 32(42.7%), California 21(28%), and Texas 22(29.3%). A hierarchical linear regression analysis demonstrated the combination of predictors (MAI, Anxiety, Concentration, and Time Management [r=0.83; p2=0.35; p2=0.34; p2=0.31;

Challenges and progresses made on the microkinetic description of lignin liquefaction: Application of group contribution methods

In this presentation a comprehensive microkinetic modelling framework and experimental tools are used to describe product yield and composition of direct lignin liquefaction processes with and without solvents (See Figure 1). With the framework proposed we aim to develop a unified theory and models capable of describing both dry (pyrolysis) and wet (hydrothermal and solvolysis) lignin liquefaction processes. An important phenomenon that has been shown to occur during lignin pyrolysis (as well as cellulose) is the formation of a liquid intermediate phase, and subsequent ejection of heavy products (\u3e~250 Da) as aerosols from this intermediate. In our presentation we will focus on the nature of lignin pyrolysis liquid intermediate through analysis of phase change equilibria temperatures for relevant lignin fragments, using group contribution methods. Specifically, estimation of boiling (Tb) and melting (Tm) points of lignin fragments was done using ARTIST software (Dortmund Data Bank Software & Separation Technology, GmbH). In total, 50 different lignin fragments were drawn, and their boiling and melting temperatures were calculated. The 50 fragments include monomers, dimers, trimers and tetrameters, with a variety of H, G and S units and inter-unit linkages. Figure 2 shows the calculated phase-change equilibria temperatures plotted against the number of aromatic units in a given lignin fragment. The dotted line at 400 °C is included as the approximate temperature at which both rupture of aliphatic linkages and conversion of short aromatic ring substituents occurs, but is less than the temperature for rearrangement of polycyclic structures. The collection of lignin fragments, such that Tm \u3c 400 \u3c Tb, make up the set of molecules that can exist as a liquid intermediate during pyrolysis, and are therefore the ones that have potential to be ejected as aerosols. The average lignin fragment in this range has 2.50 (± 0.11, standard error) aromatic units, molecular weight of 414 (± 20) Da, melting point of 292 (± 13) °C, and boiling point of 573 (± 19) °C. Relying solely on this analysis, one would expect these to be characteristics of an average molecule ejected as a liquid-phase aerosol during pyrolysis of lignin. Based on the quantification of phase equilibria temperatures, this liquid state can contain dimers and trimers, but typically not tetrameters or larger (they will preferentially depolymerize), or monomers (they will vaporize). It is these dimer and trimer products that should make up the majority of the heavy liquid products collected as aerosols. In order to validate this model, comparison was made with previously published work from Pecha, et al. (Ind. Eng. Chem. Res., 56, 2017, 9079-9089) and Bai, et al. (Fuel, 128, 2014, 170-179), who analyzed lignin pyrolysis oil with FT-ICR-MS. There is good agreement between the weights of species detected experimentally in these studies and those determined in this work based on group contribution calculations. Please click Additional Files below to see the full abstract

Extreme weather events in Myanmar: data needs for more effective humanitarian action

Extreme weather events, such as floods and cyclones, have increased in number in recent years. At the same time, there is growing evidence that providing for anticipatory humanitarian action – rather than post-event action – can give the affected populations more dignity, security and time in dealing with the impact of these shocks. Such anticipatory action, however, requires accurate weather forecasts, as well as mechanisms to provide financial resources on an ongoing basis. David MacLeod, Evan Easton-Calabria, Erin Coughlan de Perez and Catalina Jaime present research findings that evaluate both these factors in the context of Myanmar, one of the countries most at risk in its region

Comparison among technical and milled wood lignins through principal component analysis of FTIR spectra

With the growth of biomass processing in biorefineries, there is an increasing need to develop rapid and simple methods for biomass characterization. One important component of biomass that is of signification interest in pyrolysis and liquefaction research is lignin, which is the world’s predominant source of renewable aromatic carbon. Due to its complex, heterogeneous nature and distinct variations among different biomass feedstocks, the characterization of lignins presents a unique challenge. In this study, we will show that clear divisions and comparisons can be made among a variety of lignins based on their FTIR spectra quantitatively assessed through principal component analysis (PCA). The eight lignins so far characterized are: two varieties of softwood kraft, one hardwood kraft, corn stover milled wood lignin (MWL), Douglas fir MWL, hybrid poplar MWL, wheat straw soda, and wheat straw organosolv. These samples were analyzed using a Bruker Alpha FTIR-ATR instrument (in addition to other characterization techniques). The spectra were baseline corrected and normalized, and the intensities of 15 peaks were recorded. The 15 spectral peaks were chosen based on previous work published by Li and McDonald (Industrial Crops and Products, 62, 2014, 67-76). PCA and data visualization was done using Python in the Jupyter Notebook environment. Fig. 1: Explained Variance of Each PC Principal component analysis revealed that among the eight lignins, they can be qualitatively grouped based on both their feedstock variety (e.g., hardwood, softwood) and isolation method (i.e., kraft, MWL, soda, organosolv). Quantification of the explained variances for each principal component (PC) suggests that three PC’s are necessary to capture over 90% of the variation among the samples (Figure 1). The principal component plots (Figure 2) show that softwood kraft lignins are clustered, corn stover and Douglas fir MWLs are clustered, and hardwood kraft and wheat straw soda are clustered. The two wheat straw and two hardwood samples tend to have positive values for PC1, while the softwoods and corn stover are negative. The MWLs are closely grouped along PC2, and the organosolv wheat straw is uniquely large along PC3. Depending on which of the three PC plots are assessed, other possible groupings can be reasonably drawn, suggesting that the FTIR spectral characteristics of lignins are distinctly affected by both their original biomass feedstock and isolation or extraction method. The analysis of FTIR spectra with PCA is a simple and efficient way to quickly assess the characteristics of an unknown or poorly-understood lignin sample, based on its comparison with other well-studied lignins. Previous work has shown that PCA is a robust technique for analyzing bio-oil MS data (Jia, et al., Energy & Fuels, 29, 2015, 7364-7374; Pattiya, et al., Fuel, 89(1), 2010, 244-253), and this work shows that such analysis can easily be extended to FTIR spectra of contrasting lignins. Continuing research will further assess the FTIR data for other important characteristics (both qualitative and quantitative), as well as to include additional technical lignins in the analyses. Please click Additional Files below to see the full abstract

Beyond the forecast: knowledge gaps to anticipate disasters in armed conflict areas with high forced displacement

Although conflict-affected populations are often exposed to and severely impacted by disasters, little is known about their perceptions and practices concerning early warning and early action (EWEA) or how EWEA strategies can protect communities affected by conflict- and climate-related disasters. This is particularly problematic as, due to the multiple challenges posed by conflict and compound crises in these contexts, early warnings of weather hazards do not often translate in early actions. This comprehensive literature review examined 384 peer reviewed papers produced between 2004 and 2022, focused on the 20 countries most affected by non-international armed conflict and exposed to climate hazards. This paper answers the question: what is the state of knowledge of EWEA for climate hazards in countries affected by armed conflict and high levels of forced displacement? Findings demonstrate that most research focuses on climate science rather than social science across six elements of the EWEA value chain: 1. hazards analysis, 2. understanding vulnerability and exposure, 3. warning communication and dissemination, 4. forecasting availability and monitoring, 5. early action planning, and 6. financing systems. In total, 75.65% of the research studies focused on hazard analysis, forecast availability, and monitoring. There has been a strong increase in academic research on EWEA in conflict-affected countries since 2004. However, we identify that most of this research has been in Ethiopia, Pakistan, and Nigeria which, although severely affected by conflict, also have a higher level of economic development and stability. In contrast, there is little research focused on EWEA in most of the remaining countries. Across all thematic areas, there is a lack of consideration of conflict dynamics in EWEA research. This paper contributes to evidence on the need to recognize people affected by conflict in disaster risk reduction, as called for in the Sendai Framework for Action midterm review, with the aim of enhancing EWEA investments to enable tailored approaches appropriate for conflict-affected states

Elucidating pyrolysis oil oligomeric chemical structures: Experimental studies and DFT calculations

Please click Additional Files below to see the full abstrac