Selective leaching of vanadium from vanadium slag using organic acids

Abstract: Large amounts of vanadium bearing slags are produced during steel making and discarded to the environment. Bioleaching has proved that it is an environmentally friendly route which has been lately used for recovery of metals. The leaching of vanadium from a roasted slag was studied using gluconic, citric and oxalic acids. The vanadium slag was roasted at 900oC in presence of Na2CO3 prior to leaching. The effect of acid concentration, solid/liquid ratio, particles size and temperature were investigated. It was observed that at a concentration of 150mM for gluconic acid and 100mM of citric and oxalic acid, 2% of S/L ratio, -38μm and temperature of 45oC, 91, 86 and 81% of vanadium were recovered from gluconic, citric and oxalic acid respectively. Recovery of vanadium using gluconic acid is affected more by the acid concentration compared to citric and oxalic acids. The solid/ liquid ratio as well as the particle size increase have a negative effect on the recovery of each acid and the temperature increase allows to enhance the recovery

Smoke-water effect on the germination of Amazonian tree species

Smoke stimulates seed germination of a range of species from ecosystems that may or may not be fire prone. We evaluated the effects of smoke-water on germination of ten tree species of economic value in the Amazon region. Two materials were burnt to produce smoke-water: germination paper and the wood of Cecropia palmata Willd. Seven dilutions of the solutions were tested. Seeds of nine forest trees were germinated under controlled laboratory conditions (25 °C. ± 2 °C) in the laboratory. Bertholletia excelsa Humb. & Bonpl., was tested in the nursery (approximately 25-36. °C) because of its large seeds. Irrespective of the material burned, smoke-water significantly increased seed germination of three species: Cordia goeldiana Hub., Ochroma pyramidale (Cav. ex Lam.) Urb. and Jacaranda copaia (Aubl.) D. Don. and there was a significant inhibitory effect on Swietenia macrophylla King. Germination was accelerated by smoke in J. copaia, B. excelsa and Bellucia grossularioides (L.) Triana. The most pronounced effect was observed in B. excelsa, as the mean germination time of 108. d (control) was reduced to 76. d with smoke-water made from germination paper (dilution of 1:25) and to 61. d with the one from Cecropia wood (dilution of 1:250). For five of the ten species studied, smoke-water either increased or accelerated seed germination, irrespective of the materials used for its production. Seeds with low vigour and prolonged germination time seemed to be more receptive to smoke. © 2013 South African Association of Botanists

A dual laser scanning confocal and transmission electron microscopy analysis of the intracellular localization, aggregation and particle formation of African horse sickness virus major core protein VP7

The bulk of African horse sickness virus (AHSV) major core protein VP7 self-assembles into flat, hexagonal crystalline particles in a process appearing unrelated to viral replication. Why this unique characteristic of AHSV VP7 is genetically conserved, and whether VP7 aggregation and particle formation have an effect on cellular biology or the viral life cycle, is unknown. Here we investigated how different small peptide and enhanced green fluorescent protein (eGFP) insertions into the VP7 top domain affected VP7 localisation, aggregation and particle formation. This was done using a dual laser scanning confocal and transmission electron microscopy approach in conjunction with analyses of the solubility, aggregation and fluorescence profiles of the proteins. VP7 top domain modifications did not prevent trimerisation, or intracellular trafficking to one or two discrete sites in the cell. However, modifications that resulted in a misfolded and insoluble VP7-eGFP component blocked trafficking, and precluded protein accumulation at a single cellular site, perhaps by interfering with normal trimer-trimer interactions. Furthermore, the modifications disrupted the stable layering of the trimers into characteristic AHSV VP7 crystalline particles. It was concluded that VP7 trafficking is driven by a balance between VP7 solubility, trimer forming ability and trimer-trimer interactions.http://journals.cambridge.org/action/displayJournal?jid=MAM2017-06-30hb2017Genetic

African horse sickness virus NS4 protein is an important virulence factor and interferes with JAK-STAT signaling during viral infection

African horse sickness virus (AHSV) non-structural protein NS4 is a nucleocytoplasmic protein that is expressed in the heart, lung, and spleen of infected horses, binds dsDNA, and colocalizes with promyelocytic leukemia nuclear bodies (PML-NBs). The aim of this study was to investigate the role of AHSV NS4 in viral replication, virulence and the host immune response. Using a reverse genetics-derived virulent strain of AHSV-5 and NS4 deletion mutants, we showed that knockdown of NS4 expression has no impact in cell culture, but results in virus attenuation in infected horses. RNA sequencing (RNA-seq) was used to investigate the transcriptional response in these horses, to see how the lack of NS4 mediates the transition of the virus from virulent to attenuated. The presence of NS4 was shown to result in a 24 hour (h) delay in the transcriptional activation of several immune system processes compared to when the protein was absent. Included in these processes were the RIG-I-like, Toll-like receptor, and JAK-STAT signaling pathways, which are key pathways involved in innate immunity and the antiviral response. Thus, it was shown that AHSV NS4 suppresses the host innate immune transcriptional response in the early stages of the infection cycle. We investigated whether AHSV NS4 affects the innate immune response by impacting the JAK-STAT signaling pathway specifically. Using confocal laser scanning microscopy (CLSM) we showed that AHSV NS4 disrupts JAK-STAT signaling by interfering with the phosphorylation and/or translocation of STAT1 and pSTAT1 into the nucleus. Overall, these results showed that AHSV NS4 is a key virulence factor in horses and allows AHSV to overcome host antiviral responses in order to promote viral replication and spread.SUPPLEMENTARY MATERIAL: Supplementary table 1: Full list of differentially expressed genes in the transcriptome analysis. The genes were sorted according to log2Fold change values and then grouped according to up- or down-regulated genes. Days 1, 2 and 4 are presented for the horse inoculated with rAHSV-5 (NS4) and days 1 and 2 for the horses inoculated with rAHSV-5minNS4 (minNS4). The log2FC is indicated in bold for genes differentially expressed on the same day in both NS4 and minNS4. aRanks of up- or down-regulated genes in each comparison. *Involved in innate immunity according to InnateDB.Supplementary table 2: Full list of KEGG pathways enriched by the differentially expressed genes in the transcriptome analysis. The data is displayed per day and includes the up- and down- regulated genes enriching each pathway. Pathways were sorted based on corrected P-value. Days 1, 2 and 4 are presented for the horse inoculated with rAHSV-5 (NS4) and days 1 and 2 for the horses inoculated with rAHSV-5minNS4 (minNS4).Supplementary Figure 1: Images obtained from post-mortem examination of horses inoculated with rAHSV-5. Classical lesions of disease such as frothing from the nostrils (a), interstitial and subpleural lung edema (b, e), alveolar edema (c, f) and hydropericardium (d, g) were observed.Deltamune (Pty) Ltd, the University of Pretoria Institutional Research Themes, the Poliomyelitis Research Foundation, South Africa and the Genomics Research Institute, University of Pretoria. Postgraduate support was received from the Poliomyelitis Research Foundation, South Africa, the National Research Foundation, South Africa and the University of Pretoria, South Africa.http://www.elsevier.com/locate/virusreshj2022BiochemistryGeneticsMicrobiology and Plant Patholog

Determination of the physicochemical and microbiological quality of carcass, bone and blood meal

The pH value and the moisture, fat and protein content of abattoir by products which are commercially available in the Republic of South Africa were examined, and the total bacterial count and the extent of Salmonella, Escherichia coli, Bacillus, yeast and fungus contamination were determined. The extremes and reasonably attainable quality standards were deduced from the highest frequency and mean values of these figures. The total bacterial count was not statistically predictable from variables such as pH, moisture, protein and fat, but was found to be related to the combined effect of all 4 independent variables.The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Hiding in Plain Sight-Ancient Chinese Anatomy

For thousands of years, scientists have studied human anatomy by dissecting bodies. Our knowledge of their findings is limited, however, both by the subsequent loss of many of the oldest texts, and by a tendency towards a Eurocentric perspective in medicine. As a discipline, anatomy tends to be much more familiar with ancient Greek texts than with those from India, China or Persia. Here we show that the Mawangdui medical texts, entombed in the Mawangdui burial site in Changsha, China 168BCE, are the oldest surviving anatomical atlas in the world. These medical texts both predate and inform the later acupuncture texts which have been the foundation for acupuncture practice in the subsequent two millennia. The skills necessary to interpret them are diverse, requiring the researcher firstly to read the original Chinese, and secondly to perform the anatomical investigations that allow a re-viewing of the structures that the texts refer to. Acupuncture meridians are considered to be esoteric in nature, but these texts are clearly descriptions of the physical body. As such, they represent a previously hidden chapter in the history of anatomy, and a new perspective on acupuncture

An exploration of ambigrammatic sequences in narnaviruses

Narnaviruses have been described as positive-sense RNA viruses with a remarkably simple genome of ~3 kb, encoding only a highly conserved RNA-dependent RNA polymerase (RdRp). Many narnaviruses, however, are 'ambigrammatic' and harbour an additional uninterrupted open reading frame (ORF) covering almost the entire length of the reverse complement strand. No function has been described for this ORF, yet the absence of stops is conserved across diverse narnaviruses, and in every case the codons in the reverse ORF and the RdRp are aligned. The >3 kb ORF overlap on opposite strands, unprecedented among RNA viruses, motivates an exploration of the constraints imposed or alleviated by the codon alignment. Here, we show that only when the codon frames are aligned can all stop codons be eliminated from the reverse strand by synonymous single-nucleotide substitutions in the RdRp gene, suggesting a mechanism for de novo gene creation within a strongly conserved amino-acid sequence. It will be fascinating to explore what implications this coding strategy has for other aspects of narnavirus biology. Beyond narnaviruses, our rapidly expanding catalogue of viral diversity may yet reveal additional examples of this broadly-extensible principle for ambigrammatic-sequence development