Comparative Effects of Propylene Oxide, Sodium and Autoclaving on Selected Soil Properties

Samples of soil (25 g) were treated with 1 or 2 ml of propylene oxide, 400 or 800 parts/10? of sodium azide, or autoclaved for 1.5 or 3.0 h. Soil sterilization was achieved by the propylene oxide and autoclaving treatments. Sodium azide inhibited the bacteria and actinomycetes and drastically reduced the fungal population. The autoclaving treatment decreased the soil pH 0.2 unit, while propylene oxide and sodium azide treatments increased it 0.5-1.1 units. Extractable manganous—Mn was increased 2- to 3-fold by all treatments except for a 90- to 120-fold increase in an autoclaved soil; extractable Ca was not affected; and the extractable K changes were slight. Total extractable N was increased 10-20 parts/10?, and available P was generally increased by the treatments. Propylene oxide induced the least chemical alterations upon sterilization and is considered an appropriate sterilant to study chemical transformations in soils; but, germination and growth of wheat and alfalfa were retarded in propylene oxide treated soil

Panel. Community Engagement and Interpreting Slavery in North Mississippi

The “Behind the Big House” Project / Jodi Skipper, University of Mississippi and Suzanne DavidsonBehind the Big House is a slave dwelling interpretation program in Holly Springs, Mississippi. The program offers a counter-narrative to the Holly Springs Annual Pilgrimage Tour of Historic Homes and Churches, the city’s main tourist attraction which has historically neglected the contributions of enslaved persons. Behind the Big House was initiated by several private property owners who understood that interpreting the structures which housed enslaved persons could help to remedy such omissions. In addition to discussing how historical memory impacts the functions of these sites in the present, Skipper will discuss her role as a Behind the Big House tour guide, and how she incorporates the tour as an applied component in her courses. Slavery and Its Descendants / W. Ralph Eubanks, University of MississippiThe legacy of slavery and its impact across generations of African Americans is often ignored or overlooked, particularly by institutions that benefited from enslaved labor. The University of Mississippi is no exception. Payment records from the 1840s in the archives of the University of Mississippi indicate that Robert Sheegog—who once owned Faulkner’s home Rowan Oak—along with other local slave owners, loaned slaves to the University. This connection between the slaves of Rowan Oak and the building of the University of Mississippi holds the potential to redefine the idea of legacy connections to the University, since inevitably the descendants of several of those slaves are among the university’s alumni. This paper will discuss the on-going work of the University of Mississippi’s slavery research group and the possible outcomes of planned genealogical research to find the descendants of the slaves from Faulkner’s Rowan Oak who built the university.The University of Mississippi Slavery Research Group / Jeffrey Jackson and Charles K. Ross, University of MississippiIn this presentation, we present the story of the University of Mississippi Slavery Research Group focusing on its origins and the various factors that led to its formation. We highlight some of the groups’ most significant recent efforts to better understand how antebellum slavery shaped the formation of the University of Mississippi and life in North Mississippi generally and we discuss some of our initial projects and initiatives that seek to remember, memorialize and interpret the lives of enslaved people for our students, our local community, and our nation.Interpreting Slavery at Burns Belfry and Rowan Oak / George McDaniel, Burns-Belfry African American History MuseumCaroline Barr was a foundational figure in the life of William Faulkner. As he called her, “Mammy Callie,” she had worked for the Falkner family since he was a young boy. Her house and her story demand a further interpretation beyond the gates of Rowan Oak. Using her as a point of departure, this talk will explore African American history within the larger context of the town of Oxford. It will also look at the ways in which that history is being interpreted today and how that interpretation can be improved through building connections between different historical sites. This connectivity allows for a deeper understanding of African American history in Oxford and the world in which Faulkner lived and wrote

Weak Interactions in Dimethyl Sulfoxide (DMSO)-Tertiary Amide Solutions: The Versatility of DMSO as a Solvent

The structures of equimolar mixtures of the commonly used polar aprotic solvents dimethylformamide (DMF) and dimethylacetamide (DMAc) in dimethyl sulfoxide (DMSO) have been investigated via neutron diffraction augmented by extensive hydrogen/deuterium isotopic substitution. Detailed 3-dimensional structural models of these solutions have been derived from the neutron data via Empirical Potential Structure Refinement (EPSR). The intermolecular center-of-mass (CoM) distributions show that the first coordination shell of the amides comprises ∼13-14 neighbors, of which approximately half are DMSO. In spite of this near ideal coordination shell mixing, the changes to the amide-amide structure are found to be relatively subtle when compared to the pure liquids. Analysis of specific intermolecular atom-atom correlations allows quantitative interpretation of the competition between weak interactions in the solution. We find a hierarchy of formic and methyl C-H···O hydrogen bonds forms the dominant local motifs, with peak positions in the range of 2.5-3.0 Å. We also observe a rich variety of steric and dispersion interactions, including those involving the O═C-N amide π-backbones. This detailed insight into the structural landscape of these important liquids demonstrates the versatility of DMSO as a solvent and the remarkable sensitivity of neutron diffraction, which is critical for understanding weak intermolecular interactions at the nanoscale and thereby tailoring solvent properties to specific applications

Strong structuring arising from weak cooperative O-H···π and C-H···O hydrogen bonding in benzene-methanol solution

Weak hydrogen bonds, such as O-H···π and C-H···O, are thought to direct biochemical assembly, molecular recognition, and chemical selectivity but are seldom observed in solution. We have used neutron diffraction combined with H/D isotopic substitution to obtain a detailed spatial and orientational picture of the structure of benzene-methanol mixtures. Our analysis reveals that methanol fully solvates and surrounds each benzene molecule. The expected O-H···π interaction is highly localised and directional, with the methanol hydroxyl bond aligned normal to the aromatic plane and the hydrogen at a distance of 2.30 Å from the ring centroid. Simultaneously, the tendency of methanol to form chain and cyclic motifs in the bulk liquid is manifest in a highly templated solvation structure in the plane of the ring. The methanol molecules surround the benzene so that the O-H bonds are coplanar with the aromatic ring while the oxygens interact with C-H groups through simultaneous bifurcated hydrogen bonds. This demonstrates that weak hydrogen bonding can modulate existing stronger interactions to give rise to highly ordered cooperative structural motifs that persist in the liquid phase

Design of hyperporous graphene networks and their application in solid-amine based carbon capture systems

We demonstrate a simple and fully scalable method for obtaining hierarchical hyperporous graphene networks of ultrahigh total pore volume by thermal-shock exfoliation of graphene-oxide (exfGO) at a relatively mild temperature of 300 °C. Such pore volume per unit mass has not previously been achieved in any type of porous solid. We find that the amount of oxidation of starting graphene-oxide is the key factor that determines the pore volume and surface area of the final material after thermal shock. Specifically, we emphasize that the development of the hyperporosity is directly proportional to the enhanced oxidation of sp2 C[double bond, length as m-dash]C to form C[double bond, length as m-dash]O/COO. Using our method, we reproducibly synthesized remarkable meso-/macro-porous graphene networks with exceptionally high total pore volumes, exceeding 6 cm3 g−1. This is a step change compared to ≤3 cm3 g−1 in conventional GO under similar synthetic conditions. Moreover, a record high amine impregnation of >6 g g−1 is readily attained in exfGO samples (solid-amine@exfGO), where amine loading is directly controlled by the pore-structure and volume of the host materials. Such solid-amine@exfGO samples exhibit an ultrahigh selective flue-gas CO2 capture of 30–40 wt% at 75 °C with a working capacity of ≈25 wt% and a very long cycling stability under simulated flue-gas stream conditions. To the best of our knowledge, this is the first report where a graphene-oxide based hyperporous carbon network is used to host amines for carbon capture application with exceptionally high storage capacity and stability

Quality improvement program decreases mortality after cardiac surgery

ObjectiveThis study investigated the effects of a quality improvement program and goal-oriented, multidisciplinary protocols on mortality after cardiac surgery.MethodsPatients were divided into two groups: those undergoing surgery (coronary artery bypass grafting, isolated valve surgery, or coronary artery bypass grafting and valve surgery) after establishment of the multidisciplinary quality improvement program (January 2005–December 2006, n = 922) and those undergoing surgery before institution of the program (January 2002–December 2003, n = 1289). Logistic regression and propensity score analysis were used to adjust for imbalances in patients' preoperative characteristics.ResultsOperative mortality was lower in the quality improvement group (2.6% vs 5.0%, P < .01). Unadjusted odds ratio was 0.5 (95% confidence interval 0.3–0.8, P < .01); propensity score–adjusted odds ratio was 0.6 (95% confidence interval 0.4–0.99, P = .04). In multivariable analysis, diabetes (P < .01), chronic renal insufficiency (P = .05), previous cardiovascular operation (P = .04), congestive heart failure (P < .01), unstable angina (P < .01), age older than 75 years (P < .01), prolonged pump time (P < .01), and prolonged operation (P = .05) emerged as independent predictors of higher mortality after cardiac surgery, whereas quality improvement program (P < .01) and male sex (P = .03) were associated with lower mortality. Mortality decline was less pronounced in patients with than without diabetes (P = .04).ConclusionApplication of goal-directed, multidisciplinary protocols and a quality improvement program were associated with lower mortality after cardiac surgery. This decline was less prominent in patients with diabetes, and focused quality improvement protocols may be required for this subset of patients

Buried (drift-filled) hollows in London – a review of their location and key characteristics

All data generated or analysed during this study are included in this published article (and its supplementary information files). For several features where the raw data are confidential contact the author, Amy Flynn, to seek permission.© 2020 The Author(s). This paper compiles new and existing information relating to features frequently referred to as drift-filled hollows located within London. The key aim of this paper is to update the article written by Berry (1979, ‘Late Quaternary scour-hollows and related features in central London’, QJEG, 12, 9–29, doi: 10.1144/GSL.QJEG.1979.012.01.03), producing a resource for both engineering projects and academic research. Fifty-four additional drift-filled hollows have been identified and their physical characteristics are tabulated where available information allows. A case study of the Nine Elms area is presented. The drift-filled hollows have been identified through examination and critical, quality assessment of historical borehole records, site investigation records, construction records and published articles. This enlarged dataset illustrates the high level of variability between features and, as a result, it is proposed that these features did not form due to a single process, but to differing processes.Engineering and Physical Sciences Research Council (EPSRC)