Something Rotten! Poster Illustration

Providence College Department of Theatre, Dance & Film Something Rotten! poster illustration by Trevor Elliot, Technical Directorhttps://digitalcommons.providence.edu/something_rotten_pubs/1013/thumbnail.jp

Hydrogeochemical and isotopic indicators of vulnerability and sustainability in the GAS aquifer, São Paulo State, Brazil

Study region: The Guarani Aquifer System (GAS), São Paulo State, Brazil, an important freshwater resource regionally and part of a giant, transboundary system. Study focus: Groundwaters have been sampled along a transect. Based on environmental tracers (REEs, Br, B, δ11B, Sr, 87Sr/86Sr) aquifer vulnerability and sustainability issues are identified. New hydrological insights for the region: For sites near to aquifer outcrop, REE and Sr signatures (and relatively light δ13C) trace possible vertical recharge from flood basalts directly overlying the GAS. This highlights aquifer vulnerability where confined by fewer basalts and/or having cross-cutting fractures. 14C activities for these waters, however, suggest the impact of this recharge is significantly delayed in reaching the GAS. Anthropogenic sources for boron are not currently encountered; δ11B highlights feldspar dissolution, isotopically lighter signatures in the deepest sampled GAS waters resulting from pH/hydrochemical speciation changes downgradient. Br/Cl signatures (and heavier δ18O, δ2H) in these latter samples appear to reflect a past climatic signature emplaced under more arid conditions; carbon isotope systematics (δ13C, 14C) support that these represent fossil waters, and care must be taken in their water resources management in regard to sustainability of abstraction. δ18O, δ34S (sulfate) signatures confirm hydrological arguments that waters leak out of the base of the GAS aquifer in this locality rather than underlying formations with poorer water quality potentially mixing in, although other deep GAS waters in the region do show this inter-aquifer mixing. Keywords: Environmental Tracers (REEs, Br/Cl, B, δ11B, Sr, 87Sr/86Sr), Groundwater, Guarani Aquifer System (GAS), São Paulo State, Aquifer vulnerability, Aquifer sustainabilit

CCR5 HIV-1 receptor predominance in adult male prepuce; the major entry route for HIV-1 in indigenous black males in zambia?

HIV-1 entry requires not only CD4 molecule but also CCR5 (CD 195) and CXCR4 (CD 184) coreceptors. A number of randomised controlled trials in Africa have reported that male circumcision (MC) reduces the risk of HIV-1 acquisition by up to 60%. Other studies have reported that sexually transmitted infections (STIs) increase the risk of infection by HIV via an inflammatory  recruitment of more HIV target cells to the foreskin. Our aim was to compare the density of HIV-1 co-receptors (CCR5 and CXCR4) in naïve penile prepuce of neonates and penile prepuce of adults with and without history of ulcerative STIs at Male Circumcision Centres in Lusaka, Zambia. Twenty (20) fresh foreskin samples were included: five (5) from neonates, ten (10) from adult males without history of ulcerative STIs and five (5) from adult males with a history of ulcerative STIs. Immediately following MC, fresh foreskin specimens were fixed using 10% normal buffered formalin and transported to University Teaching Hospital (UTH) where tissues were processed and stained with anti-CD 195 and anti-CD 184 antibodies. Neonatal penile foreskin co-receptor mean density for CCR5 and CXCR4 was  13±5.148/mm2 and 7±1.581/mm2 respectively. CCR5 mean density of adults without past history of ulcerative STIs was 42.1±11.874/mm2 while those with history of ulcerative STIs was 78.6±13.520/mm2. Densities of CCR5 were all statistically  significant with both having Pvalue of 0.000. CXCR4 mean density was 18.6±4.812/mm2 in adults without past history ofulcerative STIs and 23.4±4.393/mm2 in those with history of ulcerative STIs giving an insignificant P-value of 0.084. It could be concluded that CCR5 co-receptors provide major entry route for HIV-1 in male adults and that CCR5 seemed to be mobilized more than CXCR4 to the prepuce during inflammation. This supports evidence that MC reduces CCR5 co-receptors for acquisition and transmission of R5 strains of HIV-1.Key words: HIV, CCR5, CD 195, CD 184

Comparison between the density of Langerhans’ cells in the prepuce of neonates and adult males

Langerhans cells (LCs) in epidermis function as sentinel antigen-presenting cells that can capture invading viruses like Herpes Simplex Virus, Varicella-zoster virus and Human  Immunodeficiency Virus (HIV). This interaction between  Langerhans cells and viruses is highly variable depending on the virus. Herpes Simplex induces apoptosis in LCs but HIV does not, instead it presents the HIV to T-cells in lymph nodes which in turn get infected. Langerhans cells in the prepuce are therefore, a portal of entry for HIV. Hence, world health organisation  recommends male circumcision to reduce the densities of  Langerhans cells. Fifteen fresh foreskins were obtained from adult males aged 18 years and above after circumcision, five had past history of ulcerative STI and five fresh foreskins were obtained from neonates. The specimens were fixed using 10% buffered formalin and transported to the histopathology laboratory where the tissues were grossed examined and embedded using paraffin wax. The formalin fixed paraffin blocks were then sectioned into 3-5um sections and then followed by immunohistochemistry staining. The primary monoclonal antibodies (anti-CD1a) targeting Langerhans cells were used and LCs counting was done. The mean Langerhans cells density in neonates was  36.6±5.273/mm2,while adults without past history of ulcerative STIs was 69.4±8.847/mm2 and those with history of ulcerative STIs was 88.4±7.273/mm2.Both age and past history of ulcerative STIs have an influence on the density of Langerhans cell on the prepuce. The neonates showed lower densities than adults. Adults with history of ulcerative STIs had higher densities than those without. Uncircumcised individuals with history of ulcerative STIs maybe more susceptible to acquisition and transmission of HIV through the prepuce than those without such history due to greater LCs densities.Key words: Human Immunodeficiency Virus (HIV), Acquired Immunodeficiency Syndrome (AIDS), Langerhans Cells (LC),Sexually Transmitted Infections (STI)

Facile Protocol for Water-Tolerant “Frustrated Lewis Pair”-Catalyzed Hydrogenation

Despite rapid advances in the field of metal-free, “frustrated Lewis pair” (FLP)-catalyzed hydrogenation, the need for strictly anhydrous reaction conditions has hampered wide-scale uptake of this methodology. Herein, we report that, despite the generally perceived moisture sensitivity of FLPs, 1,4-dioxane solutions of B(C6F5)3 actually show appreciable moisture tolerance and can catalyze hydrogenation of a range of weakly basic substrates without the need for rigorously inert conditions. In particular, reactions can be performed directly in commercially available nonanhydrous solvents without subsequent drying or use of internal desiccants

Novel B(Ar')2(Ar'') hetero-tri(aryl)boranes: a systematic study of Lewis acidity

A series of homo- and hetero-tri(aryl)boranes incorporating pentafluorophenyl, 3,5-bis(trifluoromethyl)phenyl, and pentachlorophenyl groups, four of which are novel species, have been studied as the acidic component of frustrated Lewis pairs for the heterolytic cleavage of H2. Under mild conditions eight of these will cleave H2; the rate of cleavage depending on both the electrophilicity of the borane and the steric bulk around the boron atom. Electrochemical studies allow comparisons of the electrophilicity with spectroscopic measurements of Lewis acidity for different series of boranes. Discrepancies in the correlation between these two types of measurements, combined with structural characterisation of each borane, reveal that the twist of the aryl rings with respect to the boron-centred trigonal plane is significant from both a steric and electronic perspective, and is an important consideration in the design of tri(aryl)boranes as Lewis acids

K2 Discovers a Busy Bee: An Unusual Transiting Neptune Found in the Beehive Cluster

Open clusters have been the focus of several exoplanet surveys but only a few planets have so far been discovered. The \emph{Kepler} spacecraft revealed an abundance of small planets around small, cool stars, therefore, such cluster members are prime targets for exoplanet transit searches. Kepler's new mission, K2, is targeting several open clusters and star-forming regions around the ecliptic to search for transiting planets around their low-mass constituents. Here, we report the discovery of the first transiting planet in the intermediate-age (800 Myr) Beehive cluster (Praesepe). K2-95 is a faint ($\mathrm{Kp = 15.5\,mag}$) $\mathrm{M3.0\pm0.5}$ dwarf from K2's Campaign 5 with an effective temperature of $\mathrm{3471 \pm 124\,K}$, approximately solar metallicity and a radius of $\mathrm{0.402 \pm 0.050 \,R_\odot}$. We detected a transiting planet with a radius of $\mathrm{3.47^{+0.78}_{-0.53} \, R_\oplus}$ and an orbital period of 10.134 days. We combined photometry, medium/high-resolution spectroscopy, adaptive optics/speckle imaging and archival survey images to rule out any false positive detection scenarios, validate the planet, and further characterize the system. The planet's radius is very unusual as M-dwarf field stars rarely have Neptune-sized transiting planets. The comparatively large radius of K2-95b is consistent with the other recently discovered cluster planets K2-25b (Hyades) and K2-33b (Upper Scorpius), indicating systematic differences in their evolutionary states or formation. These discoveries from K2 provide a snapshot of planet formation and evolution in cluster environments and thus make excellent laboratories to test differences between field-star and cluster planet populations.Comment: 14 pages, 8 figues. Accepted for publication in A

Guidance for the integrated use of hydrological, geochemical, and isotopic tools in mining operations

This paper summarizes international state-of-the-art applications and opportunities for employing and deploying hydrological, geochemical, and isotopic tools in an integrated manner for investigations of mining operations. It is intended to aid formulation of more integrated approaches for evaluating the overall sustainability of mining projects. The focus is particularly on mine waters, including: environmental water sources, mine water dynamics, and as a source and vector for pollution in the wider environment. The guidance is generic to mining projects and not just reflective of a particular extraction (e.g. coal, metalliferous, uranium) industry. A mine life cycle perspective has been adopted to highlight the potential for more integrated investigations at each stage of a mining operation. Three types of mines have been considered: new (i.e. those in the planning stage), active (i.e. working mines), and historical mines (i.e. inactive and abandoned mines). The practical usage of geochemical analyses and isotopic studies described here emphasise characterisation, dynamics, and process understanding for water quality considerations in tandem with water resource and environmental impact implications. Both environmental (i.e. ambient) and applied (i.e. injected) tracers are considered. This guide is written for scientists (including isotope specialists) who have limited or no mine water experience, environmental managers, planners, consultants, and regulators with key interests in planned, active, and legacy mining projects.The authors thank the IAEA for inviting us to collate an initial report on guidelines from 2018-06-25–28 in Vienna. We thank Chris Gammons for allowing us to use one of his fgures. We especially thank Umaya Doss Saravana Kumar, Lucia Ortega, and Araguás-Araguás from IAEA for assistance, and Andrea Nick for input during the meeting. Special thanks to our reviewers who substantially helped improve the structure and content of this guidance document

Deep Reinforcement Learning for Multi-Agent Interaction

The development of autonomous agents which can interact with other agents to accomplish a given task is a core area of research in artificial intelligence and machine learning. Towards this goal, the Autonomous Agents Research Group develops novel machine learning algorithms for autonomous systems control, with a specific focus on deep reinforcement learning and multi-agent reinforcement learning. Research problems include scalable learning of coordinated agent policies and inter-agent communication; reasoning about the behaviours, goals, and composition of other agents from limited observations; and sample-efficient learning based on intrinsic motivation, curriculum learning, causal inference, and representation learning. This article provides a broad overview of the ongoing research portfolio of the group and discusses open problems for future directions.Comment: Published in AI Communications Special Issue on Multi-Agent Systems Research in the U

Dietary Plant Sterol Esters Must Be Hydrolyzed to Reduce Intestinal Cholesterol Absorption in Hamsters

Background: Elevated concentrations of LDL cholesterol are associated with the development of atherosclerosis and therefore are considered an important target for intervention to prevent cardiovascular diseases. The inhibition of cholesterol absorption in the small intestine is an attractive approach to lowering plasma cholesterol, one that is addressed by drug therapy as well as dietary supplementation with plant sterols and plant sterol esters (PSEs). Objective: This study was conducted to test the hypothesis that the cholesterol-lowering effects of PSE require hydrolysis to free sterols (FSs). Methods: Male Syrian hamsters were fed atherogenic diets (AIN-93M purified diet containing 0.12% cholesterol and 8% coconut oil) to which one of the following was added: no PSEs or ethers (control), 5% sterol stearate esters, 5% sterol palmitate esters (PEs), 5% sterol oleate esters (OEs), 5% sterol stearate ethers (STs; to mimic nonhydrolyzable PSE), or 3% FSs plus 2% sunflower oil. The treatments effectively created a spectrum of PSE hydrolysis across which cholesterol metabolism could be compared. Metabolic measurements included cholesterol absorption, plasma and liver lipid concentration, and fecal neutral sterol and bile acid excretion. Results: The STs and the PEs and SEs were poorly hydrolyzed (1.69–4.12%). In contrast,OEs were 88.3% hydrolyzed. The percent hydrolysis was negatively correlated with cholesterol absorption (r=20.85; P \u3c 0.0001) and positively correlated with fecal cholesterol excretion (r = 0.92; P \u3c 0.0001), suggesting that PSE hydrolysis plays a central role in the cholesterol-lowering properties of PSE. Conclusions: Our data on hamsters suggest that PSE hydrolysis and the presence of FSs is necessary to induce an optimum cholesterol-lowering effect and that poorly hydrolyzed PSEs may lower cholesterol through an alternative mechanism than that of competition with cholesterol for micelle incorporation