Characterisation of the artist John Opie’s pigments, dated 1806

This paper discusses the contents of an artist’s paint box currently in the possession of St. Agnes Museum, Cornwall, UK, containing a selection of historic pigments. On its lid is a metal plaque that reads ‘John Opie 1806’. Very little is known about this paint box, so this piece of research aims to uncover some of the hidden information stored within it through identification of some of the pigments it contains. The main body of this research shows the first results obtained by the identification of a selection of the pigments from the paint box, using Fourier Transform Infra Red spectroscopy (FTIR) and optical microscopy techniques. These findings will be considered in relation to what this tells us about the artist John Opie, the authenticity of the pigments within the paint box, and the use of pigments in the early nineteenth century

Understanding the behaviour of graphene oxide in Portland cement paste

This study reports on the effect of graphene oxide (GO) on the hydration of Portland cement (PC) and industrial clinker. GO accelerates PC hydration, whereas it temporarily retards that of clinker. This difference reflects a twofold behaviour of GO in cement pastes. Retardation is due to the interaction of GO with the surface of hydrating grains, while acceleration results from a seeding effect. Gypsum causes this difference. GO is shown to have little effect on the strength of hardened pastes, and this merely relates to the change of hydration degree, as opposed to reinforcing effect formerly assumed. Overall, GO is not particularly active as a nucleation surface, as it aggregates and behaves in a similar way to inert fillers (e.g. quartz). Polycarboxylate-ether copolymer could make GO an active seed in cement pastes, as it prevents GO from aggregating. Nevertheless, this was found to occur only in alite pastes but not PC pastes

Exposed and At Risk: Opportunities to Strengthen Enforcement of Pesticide Regulations for Farmworker Safety

In May 2021, the Center for Agriculture and Food Systems published Essentially Unprotected: A Focus on Farmworker Health Laws and Policies Addressing Pesticide Exposure and Heat-Related Illness as a companion report to the Johns Hopkins Center for a Livable Future's report Essential and in Crisis: A Review of the Public Health Threats Facing Farmworkers in the US. Both reports focused on the public health threats facing farmworkers in the United States. Essentially Unprotected specifically addressed pesticide exposure and heat-related illness, highlighting the gaps in federal law in addition to state efforts to fill those gaps.This report was conceived by farmworker advocates to expand on the research and analysis contained in Essentially Unprotected. In continued partnership with Farmworker Justice, CAFS seeks to create resources to support the expansion of laws and policy that can improve conditions for workers throughout the food system. This report is part of a series that spotlights various issues affecting farmworkers where law and policy can play a role in offering protection.The direction of this report was influenced heavily by interviews with farmworker advocates in various states. Through these conversations, it became clear that the legal and regulatory landscape of pesticide law enforcement is complex given the cooperative relationship between federal and state governments and the myriad agencies involved at both levels. This resource is intended to provide clarity on pesticide regulation enforcement efforts to enable advocates and law and policymakers to identify opportunities for improvement. It concludes with a set of recommendations to better protect the health and safety of the farmworkers who comprise an integral part of our food syste

Superior multifunctional activity of nanoporous carbons with widely tuneable porosity: enhanced storage capacities for carbon-dioxide, hydrogen, water and electric charge

Nanoporous carbons (NPCs) with engineered specific pore sizes and sufficiently high porosities (both specific surface area and pore volume) are necessary for storing energy in the form of electric charges and molecules. Herein, NPCs, derived from biomass pine‐cones, coffee‐grounds, graphene‐oxide and metal‐organic frameworks, with systematically increased pore width (50 Wh kg−1 at high power density, 1000 W kg−1) are achieved to form the highest reported values among the range of carbons in the literature. The noteworthy energy storage performance of the NPCs for all five cases (CO2, H2, H2O, and capacitance in aqueous and organic electrolytes) is highlighted by direct comparison to numerous existing porous solids. A further analysis on the specific pore type governed physisorption capacities is presented

Monocyclic aromatic amines as potential human carcinogens: old is new again

Alkylanilines are a group of chemicals whose ubiquitous presence in the environment is a result of the multitude of sources from which they originate. Exposure assessments indicate that most individuals experience lifelong exposure to these compounds. Many alkylanilines have biological activity similar to that of the carcinogenic multi-ring aromatic amines. This review provides an overview of human exposure and biological effects. It also describes recent investigations into the biochemical mechanisms of action that lead to the assessment that they are most probably more complex than those of the more extensively investigated multi-ring aromatic amines. Not only is nitrenium ion chemistry implicated in DNA damage by alkylanilines but also reactions involving quinone imines and perhaps reactive oxygen species. Recent results described here indicate that alkylanilines can be potent genotoxins for cultured mammalian cells when activated by exogenous or endogenous phase I and phase II xenobiotic-metabolizing enzymes. The nature of specific DNA damage products responsible for mutagenicity remains to be identified but evidence to date supports mechanisms of activation through obligatory N-hydroxylation as well as subsequent conjugation by sulfation and/or acetylation. A fuller understanding of the mechanisms of alkylaniline genotoxicity is expected to provide important insights into the environmental and genetic origins of one or more human cancers and may reveal a substantial role for this group of compounds as potential human chemical carcinogens.National Institute of Environmental Health Sciences (PO1-ES006052)National Institute of Environmental Health Sciences (P30-ES002109

Associations between reliable changes in depression and changes in BMI, total body fatness and visceral adiposity during a 12-month weight loss trial.

We investigated associations between changes in depression and body composition over a 12-month weight loss trial. Of the 298 adults (BMI > 27 m/kg2), 219 with complete depression and body composition data were included. A 10-item Center for Epidemiologic Studies Depression Scale measured depression; dual-energy X-ray absorptiometry measured body composition. Multinomial logistic regression predicted reliable changes in depression by BMI, body fat (BF) and visceral adiposity (VAT). Multiplicative interaction terms tested modification by sex and ethnicity. Participants with increases in body composition were less likely to experience improvements in depression (BMI: RRR = 0.79 (0.68-0.91), p < 0.01; BF: RRR = 0.97 (0.94 - 0.99), p = 0.01; VAT: RRR = 0.99 (0.98-1.00), p = 0.02), but not worsening of depression (BMI: RRR = 1.29 (0.96-1.73), p = 0.10; BF: RRR = 1.04 (0.99-1.09), p = 0.15; VAT: RRR = 1.01 (1.00-1.03), p = 0.18). Sex and ethnicity interaction terms were not significant. However, the relationship was only significant among females, among non-Latinos for BMI and BF, and among Latinos for VAT. Our study supports the association between depression and obesity and highlights the need for longitudinal studies investigating VAT and depression in diverse ethnic groups

Divergent Human Cortical Regions for Processing Distinct Acoustic-Semantic Categories of Natural Sounds: Animal Action Sounds vs. Vocalizations

A major gap in our understanding of natural sound processing is knowledge of where or how in a cortical hierarchy differential processing leads to categorical perception at a semantic level. Here, using functional magnetic resonance imaging (fMRI) we sought to determine if and where cortical pathways in humans might diverge for processing action sounds vs. vocalizations as distinct acoustic-semantic categories of real-world sound when matched for duration and intensity. This was tested by using relatively less semantically complex natural sounds produced by non-conspecific animals rather than humans. Our results revealed a striking double-dissociation of activated networks bilaterally. This included a previously well described pathway preferential for processing vocalization signals directed laterally from functionally defined primary auditory cortices to the anterior superior temporal gyri, and a less well-described pathway preferential for processing animal action sounds directed medially to the posterior insulae. We additionally found that some of these regions and associated cortical networks showed parametric sensitivity to high-order quantifiable acoustic signal attributes and/or to perceptual features of the natural stimuli, such as the degree of perceived recognition or intentional understanding. Overall, these results supported a neurobiological theoretical framework for how the mammalian brain may be fundamentally organized to process acoustically and acoustic-semantically distinct categories of ethologically valid, real-world sounds

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)

Crystal Structure of the Sodium Cobaltate Deuterate Superconductor NaxCoO2o4xD2O (x=1/3)

Neutron and x-ray powder diffraction have been used to investigate the crystal structures of a sample of the newly-discovered superconducting sodium cobaltate deuterate compound with composition Na0.31(3)CoO2o1.25(2)D2O and its anhydrous parent compound Na0.61(1)CoO2. The deuterate superconducting compound is formed by coordinating four D2O molecules (two above and two below) to each Na ion in a way that gives Na-O distances nearly equal to those in the parent compound. One deuteron of the D2O molecule is hydrogen bonded to an oxygen atom in the CoO2 plane and the oxygen atom and the second deuteron of each D2O molecule lie approximately in a plane between the Na layer and the CoO2 layers. This coordination of Na by four D2O molecules leads to ordering of the Na ions and D2O molecules. The sample studied here, which has Tc=4.5 K, has a refined composition of Na0.31(3)CoO2o1.25(2)D2O, in agreement with the expected 1:4 ratio of Na to D2O. These results show that the optimal superconducting composition should be viewed as a specific hydrated compound, not a solid solution of Na and D2O (H2O) in NaxCoO2oyD2O. Studies of physical properties vs. Na or D2O composition should be viewed with caution until it is verified that the compound remains in the same phase over the composition range of the study.Comment: 22 pages, 8 figure