Reviving Decommissioned Ventilators How a Circular Economy Approach Can Assist in Tackling the South African Shortage of Ventilators during Covid-19

Sub-Saharan Africa bears the highest disease burden in human and economic costs, but commands less than one percent of global health expenditure (Aikins et al., 2010)

The myth of livelihoods through urban mining: The case of e-waste pickers in Cape Town

Waste pickers are widely acknowledged as an integral part of the formal and informal economy, diverting waste into the secondary resource economy through urban mining. Urban mining in itself is considered to be a source of livelihoods. We investigated the livelihoods of e-waste pickers through 110 surveys in Cape Town, South Africa. Waste pickers often indicated that they were engaged in the sector not by choice but by necessity, expressing that earning money is the only enjoyable aspect of their job. The results from the study substantiate that it is unlikely that waste pickers could survive on e-waste picking alone as 83.3% of reported incomes were below minimum wage, with 22.9% below the food poverty line. Thus, the majority of waste pickers collected a wide array of recyclables. We also found that the waste pickers in Cape Town engage in multiple e-waste related activities, including collection, dismantling and processing to a lesser extent. They work long hours in arduous working conditions which present multiple hazards for their health and safety. Ultimately, e-waste pickers’ incomes cannot be considered commensurate with the nature of the work. Further, e-waste picking cannot be regarded to significantly contribute to livelihoods, but is rather a survivalist strategy. The survivalist nature of the work does not allow for waste pickers to move upwards in the waste value chain and benefit from greater income opportunities. Furthermore, their lack of skills prohibits waste pickers’ transition to formal employment. With a lack of options, it is necessary to ensure that the waste sector provides opportunities for decent work to enable workers to lift themselves out of poverty.Significance:• E-waste pickers participate in multiple activities across the e-waste value chain including collection, dismantling, processing, and repair and refurbishment.• E-waste pickers in Cape Town cannot make a living on e-waste alone, and supplement their income from collecting other recyclables.• E-waste pickers work long hours in difficult working conditions which pose a threat to their health and safety.• E-waste picking is a survivalist strategy

Rearing and foraging affects bumblebee (Bombus terrestris) gut microbiota

Bumblebees are ecologically and economically important as pollinators of crop and wild plants, especially in temperate systems. Species, such as the buff-tailed bumblebee (Bombus terrestris), are reared commercially to pollinate high value crops. Their highly specific gut microbiota, characterised by low diversity, may affect nutrition and immunity and are likely to be important for fitness and colony health. However, little is known about how environmental factors affect bacterial community structure. We analyzed the gut microbiota from three groups of worker bumblebees (B. terrestris) from distinct colonies that varied in rearing and foraging characteristics: commercially reared with restricted foraging (RR); commercially reared with outside foraging (RF); and wild-caught workers (W). Contrary to previous studies, which indicate that bacterial communities are highly conserved across workers, we found that RF individuals had an intermediate community structure compared to RR and W types. Further, this was shaped by differences in the abundances of common OTUs and the diversity of rare OTUs present which we propose results from an increase in the variety of carbohydrates obtained through foraging

Discharge of dissolved black carbon from a fire-affected intertidal system

We report substantial tidal fluxes of dissolved black carbon (DBC) in a fire‐affected marsh in the northern Gulf of Mexico. DBC was molecularly determined as benzenepolycarboxylic acids in a tidal creek, adjacent rivers, and the coastal ocean. Supported by stable carbon isotope and in situ fluorescence measurements, three sources of dissolved organic carbon (DOC) were identified that mixed conservatively in the coastal system: groundwater from salt marshes, river water, and seawater. Groundwater was the main source of DBC to the creek. The highest DBC concentrations of up to 41 µmol C L−1 (7.2% of DOC) were found in the creek at low tide, compared with < 18 µmol C L−1 in all other samples. Over the studied tidal cycle, we determined a runoff (load per drainage area) of 3700 moles DBC (44 kg C) km−2 of salt marsh. This is high compared with the Apalachicola River, where the annual DBC runoff is on the order of 104 mol (120 kg C) km−2 yr−1. In the marsh, it would require ∼ 20 tidal cycles similar to the one that we studied to remove all black carbon produced during one fire event. Because a spring tide was studied, our estimate is as an upper limit. DBC is ubiquitous in the global ocean, and dissolution and subsequent lateral transport appear to be important removal mechanisms for soil black carbon. Our study, which provides a snapshot in time and space, demonstrates that tidal fluxes may be primary carriers of DBC, and therefore tidal pumping and groundwater discharge cannot be ignored in assessing the continental runoff of DBC

Geochemical and microbial community determinants of reductive dechlorination at a site biostimulated with glycerol

Biostimulation is widely used to enhance reductive dechlorination of chlorinated ethenes in contaminated aquifers. However, the knowledge on corresponding biogeochemical responses is limited. In this study glycerol was injected in an aquifer contaminated with cis-dichloroethene (cDCE), and geochemical and microbial shifts were followed for 265 days. Consistent with anoxic conditions and sulfate reduction after biostimulation, MiSeq 16S rRNA gene sequencing revealed temporarily increased relative abundance of Firmicutes, Bacteriodetes and sulfate reducing Deltaproteobacteria. In line with 13C cDCE enrichment and increased Dehalococcoides mccartyi (Dcm) numbers, dechlorination was observed towards the end of the field experiment, albeit being incomplete with accumulation of vinyl chloride. This was concurrent with i) decreased concentrations of dissolved organic carbon (DOC), reduced relative abundances of fermenting and sulfate reducing bacteria that have been suggested to promote Dcm growth by providing electron donor (H2) and essential corrinoid cofactors, ii) increased sulfate concentration and increased relative abundance of Epsilonproteobacteria and Deferribacteres as putative oxidizers of reduced sulfur compounds. Strong correlations of DOC, relative abundance of fermenters and sulfate reducers, and dechlorination imply the importance of syntrophic interactions to sustain robust dechlorination. Tracking microbial and environmental parameters that promote/preclude enhanced reductive dechlorination should aid development of sustainable bioremediation strategies. This article is protected by copyright. All rights reserved.This study was supported by a VITO/KU Leuven PhD scholarship (EU FP7 project AQUAREHAB, grant 226565) to S Atashgahi. Furthermore, S Atashgahi and H Smidt received support bya grant ofBE-Basic-FES funds from theDutch Ministry of Economic Affairs and D Springael by the InterUniversity Attraction Pole (IUAP) “m-manager” of the Belgian Science Policy (BELSPO, P7/25). We thankRichard Lookman for his assistance in the field experiment and acknowledge the China Scholarship Council for the support to Y Lu and Y Zheng.info:eu-repo/semantics/publishedVersio

Assessing the Inhibitory Potential of Kinase Inhibitors In Vitro: Major Pitfalls and Suggestions for Improving Comparability of Data Using CK1 Inhibitors as an Example

Phosphorylation events catalyzed by protein kinases represent one of the most prevalent as well as important regulatory posttranslational modifications, and dysregulation of protein kinases is associated with the pathogenesis of different diseases. Therefore, interest in developing potent small molecule kinase inhibitors has increased enormously within the last two decades. A critical step in the development of new inhibitors is cell-free in vitro testing with the intention to determine comparable parameters like the commonly used IC50 value. However, values described in the literature are often biased as experimental setups used for determination of kinase activity lack comparability due to different readout parameters, insufficient normalization or the sheer number of experimental approaches. Here, we would like to hold a brief for highly sensitive, radioactive-based in vitro kinase assays especially suitable for kinases exhibiting autophosphorylation activity. Therefore, we demonstrate a systematic workflow for complementing and validating results from high-throughput screening as well as increasing the comparability of enzyme-specific inhibitor parameters for radiometric as well as non-radiometric assays. Using members of the CK1 family of serine/threonine-specific protein kinases and established CK1-specific inhibitors as examples, we clearly demonstrate the power of our proposed workflow, which has the potential to support the generation of more comparable data for biological characterization of kinase inhibitors

Acid mine drainage biogeochemistry at Iron Mountain, California

The Richmond Mine at Iron Mountain, Shasta County, California, USA provides an excellent opportunity to study the chemical and biological controls on acid mine drainage (AMD) generation in situ, and to identify key factors controlling solution chemistry. Here we integrate four years of field-based geochemical data with 16S rRNA gene clone libraries and rRNA probe-based studies of microbial population structure, cultivation-based metabolic experiments, arsenopyrite surface colonization experiments, and results of intermediate sulfur species kinetics experiments to describe the Richmond Mine AMD system. Extremely acidic effluent (pH between 0.5 and 0.9) resulting from oxidation of approximately 1 × 10(5 )to 2 × 10(5 )moles pyrite/day contains up to 24 g/1 Fe, several g/1 Zn and hundreds of mg/l Cu. Geochemical conditions change markedly over time, and are reflected in changes in microbial populations. Molecular analyses of 232 small subunit ribosomal RNA (16S rRNA) gene sequences from six sites during a sampling time when lower temperature (<32°C), higher pH (>0.8) conditions predominated show the dominance of Fe-oxidizing prokaryotes such as Ferroplasma and Leptospirillum in the primary drainage communities. Leptospirillum group III accounts for the majority of Leptospirillum sequences, which we attribute to anomalous physical and geochemical regimes at that time. A couple of sites peripheral to the main drainage, "Red Pool" and a pyrite "Slump," were even higher in pH (>1) and the community compositions reflected this change in geochemical conditions. Several novel lineages were identified within the archaeal Thermoplasmatales order associated with the pyrite slump, and the Red Pool (pH 1.4) contained the only population of Acidithiobacillus. Relatively small populations of Sulfobacillus spp. and Acidithiobacillus caldus may metabolize elemental sulfur as an intermediate species in the oxidation of pyritic sulfide to sulfate. Experiments show that elemental sulfur which forms on pyrite surfaces is resistant to most oxidants; its solublization by unattached cells may indicate involvement of a microbially derived electron shuttle. The detachment of thiosulfate ([Image: see text]) as a leaving group in pyrite oxidation should result in the formation and persistence of tetrathionate in low pH ferric iron-rich AMD solutions. However, tetrathionate is not observed. Although a [Image: see text]-like species may form as a surface-bound intermediate, data suggest that Fe(3+ )oxidizes the majority of sulfur to sulfate on the surface of pyrite. This may explain why microorganisms that can utilize intermediate sulfur species are scarce compared to Fe-oxidizing taxa at the Richmond Mine site

Invasion is a community affair: clandestine followers in the bacterial community associated to green algae, Caulerpa racemosa, track the invasion source

Biological invasions rank amongst the most deleterious components of global change inducing alterations from genes to ecosystems. The genetic characteristics of introduced pools of individuals greatly influence the capacity of introduced species to establish and expand. The recently demonstrated heritability of microbial communities associated to individual genotypes of primary producers makes them a potentially essential element of the evolution and adaptability of their hosts. Here, we characterized the bacterial communities associated to native and non-native populations of the marine green macroalga Caulerpa racemosa through pyrosequencing, and explored their potential role on the strikingly invasive trajectory of their host in the Mediterranean. The similarity of endophytic bacterial communities from the native Australian range and several Mediterranean locations confirmed the origin of invasion and revealed distinct communities associated to a second Mediterranean variety of C. racemosa long reported in the Mediterranean. Comparative analysis of these two groups demonstrated the stability of the composition of bacterial communities through the successive steps of introduction and invasion and suggested the vertical transmission of some major bacterial OTUs. Indirect inferences on the taxonomic identity and associated metabolism of bacterial lineages showed a striking consistency with sediment upheaval conditions associated to the expansion of their invasive host and to the decline of native species. These results demonstrate that bacterial communities can be an effective tracer of the origin of invasion and support their potential role in their eukaryotic host’s adaptation to new environments. They put forward the critical need to consider the 'meta-organism' encompassing both the host and associated micro-organisms, to unravel the origins, causes and mechanisms underlying biological invasions

The myth of livelihoods through urban mining: The case of e-waste pickers in Cape Town

Waste pickers are widely acknowledged as an integral part of the formal and informal economy, diverting waste into the secondary resource economy through urban mining. Urban mining in itself is considered to be a source of livelihoods. We investigated the livelihoods of e-waste pickers through 110 surveys in Cape Town, South Africa. Waste pickers often indicated that they were engaged in the sector not by choice but by necessity, expressing that earning money is the only enjoyable aspect of their job. The results from the study substantiate that it is unlikely that waste pickers could survive on e-waste picking alone as 83.3% of reported incomes were below minimum wage, with 22.9% below the food poverty line. Thus, the majority of waste pickers collected a wide array of recyclables. We also found that the waste pickers in Cape Town engage in multiple e-waste related activities, including collection, dismantling and processing to a lesser extent

Temperature response of denitrification and anammox reveals the adaptation of microbial communities to in situ temperatures in permeable marine sediments that span 50° in latitude

Despite decades of research on the physiology and biochemistry of nitrate/nitrite-respiring microorganisms, little is known regarding their metabolic response to temperature, especially under in situ conditions. The temperature regulation of microbial communities that mediate anammox and denitrification was investigated in near shore permeable sediments at polar, temperate, and subtropical sites with annual mean temperatures ranging from -5 to 23 degrees C. Total N-2 production rates were determined using the isotope pairing technique in intact core incubations under diffusive and simulated advection conditions and ranged from 2 to 359 mu mol N m(-2) d(-1). For the majority of sites studied, N-2 removal was 2-7 times more rapid under simulated advective flow conditions. Anammox comprised 6-14% of total N-2 production at temperate and polar sites and was not detected at the subtropical site. Potential rates of denitrification and anammox were determined in anaerobic slurries in a temperature gradient block incubator across a temperature range of -1 degrees C to 42 degrees C. The highest optimum temperature (T-opt) for denitrification was 36 degrees C and was observed in subtropical sediments, while the lowest T-opt of 21 degrees C was observed at the polar site. Seasonal variation in the T-opt was observed at the temperate site with values of 26 and 34 degrees C in winter and summer, respectively. The T-opt values for anammox were 9 and 26 degrees C at the polar and temperate sites, respectively. The results demonstrate adaptation of denitrifying communities to in situ temperatures in permeable marine sediments across a wide range of temperatures, whereas marine anammox bacteria may be predominately psychrophilic to psychrotolerant. The adaptation of microbial communities to in situ temperatures suggests that the relationship between temperature and rates of N removal is highly dependent on community structure