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Tuberculosis is a respiratory disease that is treatable with antibiotics. An increasing prevalence of resistance means that to ensure a good treatment outcome it is desirable to test the susceptibility of each infection to different antibiotics. Conventionally, this is done by culturing a clinical sample and then exposing aliquots to a panel of antibiotics, each being present at a pre-determined concentration, thereby determining if the sample isresistant or susceptible to each sample. The minimum inhibitory concentration (MIC) of a drug is the lowestconcentration that inhibits growth and is a more useful quantity but requires each sample to be tested at a range ofconcentrations for each drug. Using 96-well broth micro dilution plates with each well containing a lyophilised pre-determined amount of an antibiotic is a convenient and cost-effective way to measure the MICs of several drugs at once for a clinical sample. Although accurate, this is still an expensive and slow process that requires highly-skilled and experienced laboratory scientists. Here we show that, through the BashTheBug project hosted on the Zooniverse citizen science platform, a crowd of volunteers can reproducibly and accurately determine the MICs for 13 drugs and that simply taking the median or mode of 11-17 independent classifications is sufficient. There is therefore a potential role for crowds to support (but not supplant) the role of experts in antibiotic susceptibility testing.Tuberculosis is a bacterial respiratory infection that kills about 1.4 million people worldwide each year. While antibiotics can cure the condition, the bacterium responsible for this disease

The Lower and Middle Group (LG and MG) chromitites of the Bushveld Complex in South Africa are the source of a very large portion of the global chrome supply. The recovery of platinum group elements and base metals (Ni, Cu) as by-products has the potential to add value to these chrome resources. Yet, the effectiveness of chromite and platinum-group element beneficiation circuits is highly sensitive to variations in feed composition. Mineral assemblages have been noted to be affected by surficial weathering (down to 50 m) and hydrothermal alteration. Of particular relevance is the abundance of alteration silicates, the prevailing base metal sulphides (BMS) and platinum group mineral (PGM) assemblages and mineral association which have a significant impact on recoveries and concentrate grade. The goal of this particular case study was to evaluate the potential recoverability of platinum group elements (PGE) as a by-product during chromite production in the Thaba Mine. As shown by a lot of studies, only a very minor amount of the economically important 3E (Pt,Pd,Rh) is enclosed in chromite and will therefore report to the chromite concentrate. On the other hand, the 6E (Pt, Pd, Rh, Ru, Ir and Au) grades of the mined chromitites are usually below 2 g/t and the feasibility of an additional PGE processing plant will be challenging. Therefore, a versatile and flexible geometallurgical framework is needed to identify potential PGE targets within the mine and to predict the recoverability of PGE in the ore. To extract a maximum of information at a minimal cost and material use, the framework proposed iterates between analytical work and statistical/ mathematical modelling. Here, we focus on the metallurgical test work results of unweathered LG and MG chromitites. More than 100 different diamond drill core intersections of chromitite seams were used as sample material and analyzed by automated scanning electron-based image analysis. Several properties of each sample were fed into a statistical unsupervised classification scheme to create seven mineralogically distinct clusters for a subsequent metallurgical test work at Mintek. Composited batch samples were milled and fed to a shaking table to separate the chromite as efficiently as possible. Tailings were milled to 80 % < 75 µm, sampled and fed to flotation cells. The tailings of the rougher circuit were discharged and the rougher concentrate was subsequently fed to a cleaner flotation stage. Finally, the cleaner concentrate was sampled and chemically analyzed. Batch sample results display rather homogeneous shaking table feed 3E grades, ranging from 0.43 to 0.69 ppm, while Cr2O3 concentrations display a larger variability, ranging from 35 wt% to 42 wt%. Flotation feed grades range from 0.75 to 1.96 ppm. Cleaner flotation concentrates display grades between ca. 4 ppm and 16 ppm, resulting in upgrading factors between 2 and 11. Overall 3E recovery is between 25 and above 40 %. One reason for these PGE losses could be either large and liberated PGM grains or BMS agglomerates associated with PGM and/or PGE, which would go with the chromite concentrate. To reduce losses at the chromite concentration stage a possible PGM removal upfront with coarse flotation should be considered. Secondly, creating flotation reagent regimes and increasing residence time of the ore in the flotation cells to handle complex PGM assemblages (PGE-alloys and –sulpharsenides) will increase the flotation performance. To further increase the recovery, new flotation technology for better mineral surface cleaning may promote flotation of liberated PGM, as well as increasing liberation (e.g. Mach reactor).

This study focuses on the LG-6 and LG-6A chromitite seams at the Thaba mine located on the western limb of the Bushveld Complex. Platinum group minerals and base-metal sulfides are studied by mineral liberation analysis and electron microprobe analysis to define distinct assemblages and to evaluate the potential for beneficiation. Two distinct major mineral assemblages are defined: The first assemblage is rich in PGE-sulfides and alloys of Fe and Sn as well as chalcopyrite, pentlandite while second assemblage is rich in PGE-sulfarsenides and -arsenides and -alloys of Sb and Bi, pentlandite and Co-rich pentlandite.

The rare earth elements (REE) are significant in the context of world economic growth and modern technology. This research is aimed at investigating an alternative source of REE by exploring cost-effective ways of processing REE minerals from an existing beach placer deposit operation, currently mined for titanium. In order to recover REE through economically optimum means, upfront mineralogical investigations are a necessity to reduce the ore processing costs. An approach involving mineralogical characterization and hydrometallurgical test work was therefore chosen. The sample for the study - a tailings fraction from a heavy mineral concentration plant in the titanium industry - was screened into four size classes, and each size class was mineralogically characterized. The minerals present in the sample were monazite, zircon, epidote, pyroxene, amphibole, rutile, quartz, leucoxene, titanite, and almandine. The main REE-bearing minerals, monazite and zircon, were preferentially concentrated in the finer (-150 μm) fractions, which constituted about 50 mass % of the sample and which would be amenable to direct leaching without prior upgrading to a concentrate. Leaching test work was carried out on the combined fractions passing 150 μmι. Mineralogical examination of the residues from different leach stages showed that monazite was cracked and the REE released to solution in the final leach stage. Zircon was not as reactive under the conditions used, and REE release was not expected from this mineral. The mineralogical findings were correlated against bulk chemical analyses of the leach products to establish whether a good reconciliation was achieved

The common fibular nerve (CFN), is a branch of the sciatic nerve (SN) that exits the popliteal fossa and is located at the tuberculum of the fibula. At the tuberculum of the fibula, the CFN bifurcates into deep (DFN) and superficial (SFN) fibular nerves. Forty fetuses were micro-dissected to (i) describe the course of the CFN in relation to the tuberculum and neck of the fibula in fetuses; (ii) describe the branches, distribution and relation of the DFN and SFN to muscles within the anterolateral compartment of the leg. The CFN, DFN and SFN were present in all specimens dissected; the CFN measured a mean length (mm) of 16.03 and 16.69 on the right and left sides respectively. Bifurcation of the CFN related to the tuberculum of fibula (right; left) - above 20/80 (25%); 14/80 (17.5%); below 6/80 (7.5%); 10/80 (12.5%) and at the tuberculum 54/80 (67.5%); 56/80 (70%). The DFN bifurcated into medial and lateral branches in 68/80 (85%) and 54/80 (67.5%) on the right and left sides, respectively. The SFN bifurcated into a medial branch in 78/80 (97.5%) and 76/80 (95%) on right and left sides, respectively and a lateral branch in 78/80 (97.5%) and 76/80 (95%) on right and left sides, respectively. The course and distribution of the CFN, DFN and SFN were consistent with the literature reviewed and descriptions found in standard anatomical textbooks. However, our findings show that the DFN has a variable number of branching patterns, which is unique to this fetal study and an intermediate branch of the SFN which was recorded in 3/80 cases. El nervio fibular común (NFC), es un ramo del nervio isquiático (NI) que sale de la fosa poplítea y se ubica a nivel de la cabeza de la fíbula. A ese nivel, el NFC se bifurca en los nervios fibular profundo (NFP) y superficial (NFS). Cuarenta fetos fueron micro disecados para (i) describir el curso del NFC en relación con la cabeza y cuello de la fíbula en fetos; (ii) describir los ramos, distribución y relación del NFP y NFS con los músculos dentro del compartimento anterolateral de la pierna. El NFC, NFP y NFS estuvieron presentes en todos los especímenes disecados; el NFC presentó una longitud promedio de 16,03 y 16,69 (mm) en el lado derecho e izquierdo, respectivamente. La bifurcación del NFC se relacionó con la cabeza de la fíbula del lado derecho e izquierdo: por encima en 25% y 17,5%; por debajo 7,5% y 12,5 % y a nivel de la cabeza en 67,5 % y 70%. El NFP se bifurcó en ramos medial y lateral en un 85% en el lado derecho y 67,5% en el izquierdo. El NFS se bifurcó en una ramo medial en el 97,5% y 95% en los lados derecho e izquierdo, respectivamente, y un ramo lateral en el 97,5% y 95% del lados derecho e izquierdo, respectivamente. El curso y distribución del NFC, NFP y NFS coincidieron con la literatura revisada y textos de anatómia normal. Sin embargo, observamos que el NFP tiene un número variable de patrones de ramificación, único para este estudio fetal y un ramo intermedio del NFS que fue visto en 3/80 casos.

The purpose of this study was to determine the effectiveness of a volunteer led crafts group intervention (VLCG) as an adjunct to antidepressant medication on mild to moderately depressed women. A quasi-experimental, non-equivalent, control group study was conducted in an urban, psychiatric clinic. Depression was measured using the Beck Depression Inventory (BDI) scale. At baseline, the mean BDI scores were similar between the VLCG and the Control group (CG). There were no significant differences with the BDI‘s score after six weeks of VLCG intervention (p=0.291). After 12 weeks of interventions, the BDI scores for the VLCG was reduced, whilst the CG participants had an increase in their levels of depression. VLCG intervention as an adjunct to antidepressant medication was effective in reducing the levels of depression. Keywords: Depressed women, volunteer-led crafts group intervention, Beck Depression Inventory scale, effectivenessGender & Behaviour, 10(2), December 2012

The Kalahari Manganese Deposit (KMD) is the largest land-based manganese deposit, hosting approximately 80% of the world's known, mineable manganese resources. The deposit, located near Kuruman in the Northern Cape Province of South Africa, is one of five erosional relics of the Paleoproterozoic (ca. 2.2 Ga) Hotazel Formation, with sedimentary manganese ores occurring as up to 50 m thick beds interbedded with banded iron-formation (BIF) and hematite lutite. The study focuses on the manganese ores of the Nchwaning–Gloria mining area of the northern KMD. In this area, pronounced mineralogical and major element alteration was imparted on the sedimentary manganese ores by a structurally-controlled hydrothermal fluid flow event. Most notable effects of hydrothermal alteration are the decomposition and leaching of Ca- and Mg-carbonate, and marked residual enrichment of manganese. On the basis of mineral assemblage, grade, texture and geochemical characteristics, three ore types were distinguished in the studied sample set, classified into least altered (LA), partially altered (PA) and advanced altered (AA) types. Advanced altered ores may be further classified into five different types, based on mineral assemblages that contain hausmannite and/or braunite as significant minerals. The rare earth element (REE) geochemistry of these fundamental ore types was studied in detail, to document REE mobility during hydrothermal alteration. Total REE concentrations in LA ores were found to be very low (14–22 ppm) and remarkably uniform, within the range typically observed for BIF. Hydrothermal alteration results in residual enrichment and a much larger scatter in REE contents. A small Ce anomaly observed in the protolith remains similar in magnitude when observed in PAAS-normalised REE plots. The data define, however, a power trend in the (Ce/Ce*) vs (Pr/Pr*) diagram. Such behaviour is interpreted in terms of a conservative system that was predominantly protolith-buffered. Local remobilisation of REE during hydrothermal alteration is attributed to the dissolution of diagenetic apatite and redistribution of hydrothermal trace minerals, including neoformed apatite, monazite and cerianite.

SYNOPSIS The characterization of platinum group minerals (PGMs) from concentrator flotation circuits provides valuable information towards understanding PGM recovery under given milling and flotation conditions. Additional mineralogical characterization also provides information on ore variability, which may affect recovery. Considering the low grades involved, automated scanning electron microscopy (SEM) characterization of PGMs has enabled relatively quick analyses, compared with older, time consuming and less accurate optical microscopy methods. Over the years, parameters, such as species, size distribution, liberation, gangue and base metal sulfide (BMS) associations, have been used to characterize the PGMs in a process mineralogical context, to aid metallurgical interpretation. This paper considers whether flotation indices determined for PGMs can be empirically validated, using initial results from analysis of PGMs in a concentrate bank from a South African concentrator treating UG2 ore from the western limb of the Bushveld Complex. The aim is to determine whether floatability is adequately described by these parameters, or whether other mineralogical factors must be considered when assessing PGM floatability, and hence accounting for recovery vs. losses to tails. The data obtained to date, show that flotation parameters (including liberation index, BMS/gangue relationships and size distribution) have merits where large changes in PGM concentration occur, as observed in the first four cells of the concentrate bank. Larger data sets, however, are required to assess floatability, particularly where concentrate cell grades are similar, as observed in the last six cells of the concentrate bank. Furthermore, the floatability indices could be enhanced by the incorporation of selected associated gangue mineral information, chief amongst these being the content and mode of occurrence of naturally floatable talc and associated orthopyroxene.