Detection and Understanding of Natural CO2 Releases in KwaZulu-Natal, South Africa

Natural carbon dioxide (CO2) emanates from a number of sites along a N-S trend that coincides with a mapped fault near the village of Bongwana in KwaZulu-Natal, South Africa. In addition to the natural CO2 seeps a groundwater well drilled on a farm in Bongwana encountered CO2 and now leaks. Thus the Bongwana sites provide excellent analogues for failed CO2 storage under the two primary leakage scenarios; 1) abrupt leakage through injection well failure or leakage up an abandoned well, and 2) gradual leakage, through undetected faults, fractures or wells. Here we present results from preliminary fieldwork undertaken in September 2015

Understanding microwave induced sorting of porphyry copper ores

Global demand for minerals and metals is increasing. It has been established that the impact of mining and mineral processing operations must be reduced to sustainably meet the demands of a low grade future. Successful incorporation of ore sorting in flow sheets has the potential to improve energy efficiency by rejecting non-economic material before grinding. Microwave heating combined with infra-red temperature measurement has been shown to distinguish low and high grade ore fragments from each other. In this work, experimentally validated 2-D finite difference models of a theoretical two phase ore, representing typical fragment textures and grades, are constructed. Microwave heating is applied at economically viable energy inputs and the resultant surface thermal profiles analysed up to 2 minutes after microwave heating. It is shown that the size and location of grains can dramatically alter surface temperature rise at short thermal measurement delay times and that the range of temperatures increases with increasing fragment grade. For the first time, it is suggested that increasing the delay time between microwave heating and thermal measurement can reduce the variation seen for fragments of the same grade but different textures, improving overall differentiation between high and low grade fragments

Functional diversity of chemokines and chemokine receptors in response to viral infection of the central nervous system.

Encounters with neurotropic viruses result in varied outcomes ranging from encephalitis, paralytic poliomyelitis or other serious consequences to relatively benign infection. One of the principal factors that control the outcome of infection is the localized tissue response and subsequent immune response directed against the invading toxic agent. It is the role of the immune system to contain and control the spread of virus infection in the central nervous system (CNS), and paradoxically, this response may also be pathologic. Chemokines are potent proinflammatory molecules whose expression within virally infected tissues is often associated with protection and/or pathology which correlates with migration and accumulation of immune cells. Indeed, studies with a neurotropic murine coronavirus, mouse hepatitis virus (MHV), have provided important insight into the functional roles of chemokines and chemokine receptors in participating in various aspects of host defense as well as disease development within the CNS. This chapter will highlight recent discoveries that have provided insight into the diverse biologic roles of chemokines and their receptors in coordinating immune responses following viral infection of the CNS

Le magmatisme de la région de Kwyjibo, Province\ud du Grenville (Canada) : intérêt pour les\ud minéralisations de type fer-oxydes associées

The granitic plutons located north of the Kwyjibo property in Quebec’s Grenville Province are of\ud Mesoproterozoic age and belong to the granitic Canatiche Complex . The rocks in these plutons are calc-alkalic, K-rich,\ud and meta- to peraluminous. They belong to the magnetite series and their trace element characteristics link them to\ud intraplate granites. They were emplaced in an anorogenic, subvolcanic environment, but they subsequently underwent\ud significant ductile deformation. The magnetite, copper, and fluorite showings on the Kwyjibo property are polyphased\ud and premetamorphic; their formation began with the emplacement of hydraulic, magnetite-bearing breccias, followed by\ud impregnations and veins of chalcopyrite, pyrite, and fluorite, and ended with a late phase of mineralization, during\ud which uraninite, rare earths, and hematite were emplaced along brittle structures. The plutons belong to two families:\ud biotite-amphibole granites and leucogranites. The biotite-amphibole granites are rich in iron and represent a potential\ud heat and metal source for the first, iron oxide phase of mineralization. The leucogranites show a primary enrichment in\ud REE (rare-earth elements), F, and U, carried mainly in Y-, U-, and REE-bearing niobotitanates. They are metamict and\ud underwent a postmagmatic alteration that remobilized the uranium and the rare earths. The leucogranites could also be\ud a source of rare earths and uranium for the latest mineralizing events

Vandetanib Blocks the Cytokine Storm in SARS-CoV-2-Infected Mice

The portfolio of SARS-CoV-2 small molecule drugs is currently limited to a handful that are either approved (remdesivir), emergency approved (dexamethasone, baricitinib, paxlovid, and molnupiravir), or in advanced clinical trials. Vandetanib is a kinase inhibitor which targets the vascular endothelial growth factor receptor (VEGFR), the epidermal growth factor receptor (EGFR), as well as the RET-tyrosine kinase. In the current study, it was tested in different cell lines and showed promising results on inhibition versus the toxic effect on A549-hACE2 cells (IC500.79 μM) while also showing a reduction of >3 log TCID50/mL for HCoV-229E. The in vivo efficacy of vandetanib was assessed in a mouse model of SARS-CoV-2 infection and statistically significantly reduced the levels of IL-6, IL-10, and TNF-α and mitigated inflammatory cell infiltrates in the lungs of infected animals but did not reduce viral load. Vandetanib also decreased CCL2, CCL3, and CCL4 compared to the infected animals. Vandetanib additionally rescued the decreased IFN-1β caused by SARS-CoV-2 infection in mice to levels similar to that in uninfected animals. Our results indicate that the FDA-approved anticancer drug vandetanib is worthy of further assessment as a potential therapeutic candidate to block the COVID-19 cytokine storm

Near-threshold ω\omega and ϕ\phi meson productions in pppp collisions

Using a relativistic effective Lagrangian at the hadronic level, near-threshold $\omega$ and $\phi$ meson productions in proton proton ($pp$) collisions, $p p \to p p \omega/\phi$, are studied within the distorted wave Born approximation. Both initial and final state $pp$ interactions are included. In addition to total cross section data, both $\omega$ and $\phi$ angular distribution data are used to constrain further the model parameters. For the $p p \to p p \omega$ reaction we consider two different possibilities: with and without the inclusion of nucleon resonances. The nucleon resonances are included in a way to be consistent with the $\pi^- p \to \omega n$ reaction. It is shown that the inclusion of nucleon resonances can describe the data better overall than without their inclusion. However, the SATURNE data in the range of excess energies $Q < 31$ MeV are still underestimated by about a factor of two. As for the $p p \to p p \phi$ reaction it is found that the presently limited available data from DISTO can be reproduced by four sets of values for the vector and tensor $\phi NN$ coupling constants. Further measurements of the energy dependence of the total cross section near threshold energies should help to constrain better the $\phi NN$ coupling constant.Comment: Latex, 37 pages, 13 figures (14 EPS-figure files), text modified, version to appear in Phys. ReV.

The Origin, Early Evolution and Predictability of Solar Eruptions

Coronal mass ejections (CMEs) were discovered in the early 1970s when space-borne coronagraphs revealed that eruptions of plasma are ejected from the Sun. Today, it is known that the Sun produces eruptive flares, filament eruptions, coronal mass ejections and failed eruptions; all thought to be due to a release of energy stored in the coronal magnetic field during its drastic reconfiguration. This review discusses the observations and physical mechanisms behind this eruptive activity, with a view to making an assessment of the current capability of forecasting these events for space weather risk and impact mitigation. Whilst a wealth of observations exist, and detailed models have been developed, there still exists a need to draw these approaches together. In particular more realistic models are encouraged in order to asses the full range of complexity of the solar atmosphere and the criteria for which an eruption is formed. From the observational side, a more detailed understanding of the role of photospheric flows and reconnection is needed in order to identify the evolutionary path that ultimately means a magnetic structure will erupt