Ignition Method Development and First Field Demonstration of In Situ Smouldering Remediation

Self-sustaining Treatment for Active Remediation (STAR), a smouldering combustion-based technology for remediating sites contaminated by industrial liquids, has been extensively studied in the laboratory. The technology had not been demonstrated at a real site. Moreover, the ignition method (based on heat conduction) for the process used in the laboratory was not appropriate for field deployment and an alternative was required. This work first presents the development of a new ignition method for smouldering combustion. This ignition technique (based on heat convection) was proven effective via laboratory tests, and then applied and improved through two field tests. These field tests, conducted on coal tar-contaminated soils below the water table at a former industrial facility, represent the first in situ demonstrations of the STAR technology. Self-sustained smoldering was demonstrated within two soil layers at the site: a fill located 3 m below ground surface (bgs) (shallow test) and a sand located 8 m bgs (deep test). The shallow test destroyed 3,728 kg of coal tar over 10 days while the deep test destroyed 864 kg of coal tar over 10 days. Concentration reductions of 99.3% and 97.3% were achieved in soils within the treated areas of the shallow and deep tests, respectively. The performance of the technology in the field (rate the reaction travelled, peak temperatures, extent of cleanup, spread of drying zone) was found to be consistent with the previous laboratory studies. Overall, this work successfully transitions the smouldering remediation concept shown in the laboratory to a field-proven technology with a robust ignition technique that allows rapid, effective deployment at contaminated sites

Effect of temperature and litter quality on decomposition rate of Pinus patula needle litter

AbstractThis study examined the mass loss and CO2 production from Pinus patula (Schlecht et Cham) leaf litter collected from fertilized plots in the Mpumalanga Province. Litter decomposition increased with increasing temperature. Warming between 15 and 18°C significantly increased the amount of CO2 emissions from the litter. Mass loss positively correlated with temperature levels. Nitrogen fertilizer applications had significant effects on litter decomposition rate but a minor effect on litter nitrogen quality. Litter quality was not a strong predictor of decomposition rates implying temperature is the major factor influencing the decomposition rate of Pinus patula needle litter. Results of this study are consistent with the hypothesis that the rate of nutrient cycling in non-limiting environments will increase, due primarily to an increase in litter decomposition as a result of increased temperatures

Morphology of Three Imported Aphthona Flea Beetles Used as Biological Control Agents of Leafy Spurge

The following morphological study of the three imported Aphtona flea beetles supplies a detailed description of selected structures that will distinguish each of the three imported species and will separate them from a common native fle beetle (Glyptina atriventris) found at South Dakota release sites

Above ground woody community attributes, biomass and carbon stocks along a rainfall gradient in the savannas of the central lowveld, South Africa

Enumeration of carbon stocks at benchmark sites is a necessary activity in assessing the potential carbon sequestration and possible generation of credits through restoration of intensively impacted sites. However, there is a lack of empirical studies throughout much of the savannas of sub-Saharan Africa, including South Africa. We report an estimation of species specific and site biomass and carbon stocks, and general vegetation structural attributes from three protected areas along a rainfall gradient in the central lowveld, South Africa. Estimates of biomass and carbon stocks were effected through destructive sampling to establish locally derived allometric equations. There was a gradient of increasing woody density, height of the canopy, number of species, density of regenerative stems and a greater proportion of stems in small size classes from the arid locality to the mesic locality, with the semi-arid locality being intermediate. The proportion of spinescent species decreased with increasing rainfall. The mesic locality was significantly more woody than either the arid or semi-arid sites, having double the biomass, four times the density and 40% higher basal area. Above ground carbon pools were also higher; carbon stocks were approximately 9 t/ha for the arid and semi-arid sites and 18 t/ha for the mesic site

CATH functional families predict functional sites in proteins

MOTIVATION: Identification of functional sites in proteins is essential for functional characterization, variant interpretation and drug design. Several methods are available for predicting either a generic functional site, or specific types of functional site. Here, we present FunSite, a machine learning predictor that identifies catalytic, ligand-binding and protein-protein interaction functional sites using features derived from protein sequence and structure, and evolutionary data from CATH functional families (FunFams). RESULTS: FunSite's prediction performance was rigorously benchmarked using cross-validation and a holdout dataset. FunSite outperformed other publicly-available functional site prediction methods. We show that conserved residues in FunFams are enriched in functional sites. We found FunSite's performance depends greatly on the quality of functional site annotations and the information content of FunFams in the training data. Finally, we analyse which structural and evolutionary features are most predictive for functional sites. AVAILABILITY: https://github.com/UCL/cath-funsite-predictor. CONTACT: [email protected]. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online

Droughts and the ecological future of tropical savanna vegetation

1. Climate change is expected to lead to more frequent, intense and longer droughts in the future, with major implications for ecosystem processes and human livelihoods. The impacts of such droughts are already evident, with vegetation dieback reported from a range of ecosystems, including savannas, in recent years. 2. Most of our insights into the mechanisms governing vegetation drought responses have come from forests and temperate grasslands, while responses of savannas have received less attention. Because the two life forms that dominate savannas—C3 trees and C4 grasses—respond differently to the same environmental controls, savanna responses to droughts can differ from those of forests and grasslands. 3. Drought‐driven mortality of savanna vegetation is not readily predicted by just plant drought‐tolerance traits alone, but is the net outcome of multiple factors, including drought‐avoidance strategies, landscape and neighborhood context, and impacts of past and current stressors including fire, herbivory and inter‐life form competition. 4. Many savannas currently appear to have the capacity to recover from moderate to severe short‐term droughts, although recovery times can be substantial. Factors facilitating recovery include the resprouting ability of vegetation, enhanced flowering and seeding and post‐drought amelioration of herbivory and fire. Future increases in drought severity, length and frequency can interrupt recovery trajectories and lead to compositional shifts, and thus pose substantial threats, particularly to arid and semi‐arid savannas. 5. Synthesis. Our understanding of, and ability to predict, savanna drought responses is currently limited by availability of relevant data, and there is an urgent need for campaigns quantifying drought‐survival traits across diverse savannas. Importantly, these campaigns must move beyond reliance on a limited set of plant functional traits to identifying suites of physiological, morphological, anatomical and structural traits or “syndromes” that encapsulate both avoidance and tolerance strategies. There is also a critical need for a global network of long‐term savanna monitoring sites as these can provide key insights into factors influencing both resistance and resilience of different savannas to droughts. Such efforts, coupled with site‐specific rainfall manipulation experiments that characterize plant trait–drought response relationships, and modelling efforts, will enable a more comprehensive understanding of savanna drought responses

Ab-Initio Calculation of Molecular Aggregation Effects: a Coumarin-343 Case Study

We present time-dependent density functional theory (TDDFT) calculations for single and dimerized Coumarin-343 molecules in order to investigate the quantum mechanical effects of chromophore aggregation in extended systems designed to function as a new generation of sensors and light-harvesting devices. Using the single-chromophore results, we describe the construction of effective Hamiltonians to predict the excitonic properties of aggregate systems. We compare the electronic coupling properties predicted by such effective Hamiltonians to those obtained from TDDFT calculations of dimers, and to the coupling predicted by the transition density cube (TDC) method. We determine the accuracy of the dipole-dipole approximation and TDC with respect to the separation distance and orientation of the dimers. In particular, we investigate the effects of including Coulomb coupling terms ignored in the typical tight-binding effective Hamiltonian. We also examine effects of orbital relaxation which cannot be captured by either of these models

Where grief education goes to die? A response to making learning about grief, death, and loss mandatory in Scotland’s Curriculum for Excellence

Stephen C Scholes - ORCID: 0000-0002-5808-6121 https://orcid.org/0000-0002-5808-6121This rapid response raises challenges to Dawson et al’s (2023) recent proposals for mandatory grief education in schools; in particular, it considers curriculum crowding, the limitations of legal mandates and initial-teacher education. It proposes collaborative working between specialist groups as a way forward.N/Ahttps://www.bereavementjournal.org/index.php/bcj/article/view/1137/1142https://doi.org/10.54210/bj.2024.11373pubpub