Status of tailings dumps : let D5s go working in the past?

It was decided in the De Beers v Ataqua Mining (Pty) Ltd that \u27\u27tailings dumps\u27\u27 created by mining companies before the Mineral and Petroleum Resources Development Act, 28 of 2002 (&quot;the MPRDA&quot;) came into operation are not governed by its provisions because such dumps are not &quot;residue stockpiles&quot; or &quot;residue deposits&quot; for purposes of the MPRDA. Ownership of tailings dumps is determined by the common law principles of accession. Ownership of a movable dump has to be transferred by one of the recognised forms of delivery of movables. Processing of these dumps will, however, still be subject to compliance with South African environmental, health and safety laws in general. It is submitted that mine dumps or tailings dumps created upon the exercise of &quot;old order mining rights&quot; before the commencement of the MPRDA and even after commencement of the MPRDA until eventual termination of the &quot;old order mining rights&quot; are not subject to the extensive, mining, environmental, empowerment provisions of the MPRDA. Termination of &quot;old order mining rights&quot; takes place upon: (i) refusal of an application for conversion of a mining right during (or even after) the period of transition, (ii) conversion into and registration of new order mining rights during (or even after) the period of transition or (iii) termination of unconverted &quot;old order mining rights&quot; on 30 April 2009. To the extent that this decision has made it possible to embark on a shorter and less cumbersome route in the reprocessing and eventual disappearance of most tailings dumps, it is to be welcomed from an economical, environmental, job creation and aesthetic perspective. Proposed amendments to the MPRDA to undo the impact of the De Beers decision should be carefully considered against these mentioned benefits and a possible finding that it may amount to an expropriation without compensation. <br /

A Novel Pzg-NURF Complex Regulates Notch Target Gene Activity

The Putzig (Pzg) protein is associated with the NURF nucleosome remodeling complex, thereby promoting Notch target gene expression. Our findings suggest a novel Pzg-NURF complex that is responsible for the epigenetic regulation of Notch target genes

Genetic and phenotypic consequences of early domestication in black soldier flies (Hermetia illucens)

CITATION: Rhode, C. et al. 2020. Genetic and phenotypic consequences of early domestication in black soldier flies (Hermetia illucens). Animal Genetics. 51:752-762. doi:10.1111/age.12961The original publication is available at https://onlinelibrary.wiley.com/journal/13652052The black soldier fly, Hermetia illucens, is an emerging biotechnological agent with its larvae being effective converters of organic waste into usable bio-products including protein and lipids. To date, most operations use unimproved commercial populations produced by mass rearing, without cognisance of specific breeding strategies. The genetic and phenotypic consequences of these commercial practices remain unknown and could have a significant impact on long-term population viability and productivity. The aim of this study was thus to assess the genetic and phenotypic changes during the early phases of colony establishment and domestication in the black soldier fly. An experimental colony was established from wild founder flies and a new microsatellite marker panel was developed to assess population genetic parameters along with the phenotypic characteristics of each generational cohort under captive breeding. The experimental colony was characterised by a small effective population size, subsequent loss of genetic diversity and rapid genetic and phenotypic differentiation between the generational cohorts. Ultimately, the population collapsed by the fifth generation, most likely owing to the adverse effect of inbreeding depression following the fixation of deleterious alleles. Species with r-selected life history characteristics (e.g. short life-span, high fecundity and low larval survival) are known to pose particular challenges for genetic management. The current study suggests that sufficient genetic and phenotypic variations exist in the wild population and that domestication and strain development could be achieved with careful population augmentation and selection during the early stages of colony establishment.https://onlinelibrary.wiley.com/doi/10.1111/age.12961Publishers versio

Developing a Complex Understanding of Physical Activity in Cardiometabolic Disease from Low-to-Middle-Income Countries—A Qualitative Systematic Review with Meta-Synthesis

Physical activity behaviour is complex, particularly in low-resource settings, while existing behavioural models of physical activity behaviour are often linear and deterministic. The objective of this review was to (i) synthesise the wide scope of factors that affect physical activity and thereby (ii) underpin the complexity of physical activity in low-resource settings through a qualitative meta-synthesis of studies conducted among patients with cardiometabolic disease living in low-to-middle income countries (LMIC). A total of 41 studies were included from 1200 unique citations (up to 15 March 2021). Using a hybrid form of content analysis, unique factors (n = 208) that inform physical activity were identified, and, through qualitative meta-synthesis, these codes were aggregated into categories (n = 61) and synthesised findings (n = 26). An additional five findings were added through deliberation within the review team. Collectively, the 31 synthesised findings highlight the complexity of physical activity behaviour, and the connectedness between person, social context, healthcare system, and built and natural environment. Existing behavioural and ecological models are inadequate in fully understanding physical activity participation in patients with cardiometabolic disease living in LMIC. Future research, building on complexity science and systems thinking, is needed to identify key mechanisms of action applicable to the local context

Nutrition Strategies for Triathlon

Contemporary sports nutrition guidelines recommend that each athlete develop a personalised, periodised and practical approach to eating that allows him or her to train hard, recover and adapt optimally, stay free of illness and injury and compete at their best at peak races. Competitive triathletes undertake a heavy training programme to prepare for three different sports while undertaking races varying in duration from 20 min to 10 h. The everyday diet should be adequate in energy availability, provide CHO in varying amounts and timing around workouts according to the benefits of training with low or high CHO availability and spread high-quality protein over the day to maximise the adaptive response to each session. Race nutrition requires a targeted and well-practised plan that maintains fuel and hydration goals over the duration of the specific event, according to the opportunities provided by the race and other challenges, such as a hot environment. Supplements and sports foods can make a small contribution to a sports nutrition plan, when medical supplements are used under supervision to prevent/treat nutrient deficiencies (e.g. iron or vitamin D) or when sports foods provide a convenient source of nutrients when it is impractical to eat whole foods. Finally, a few evidence-based performance supplements may contribute to optimal race performance when used according to best practice protocols to suit the triathlete’s goals and individual responsiveness

Tramtrack Is Genetically Upstream of Genes Controlling Tracheal Tube Size in Drosophila

The Drosophila transcription factor Tramtrack (Ttk) is involved in a wide range of developmental decisions, ranging from early embryonic patterning to differentiation processes in organogenesis. Given the wide spectrum of functions and pleiotropic effects that hinder a comprehensive characterisation, many of the tissue specific functions of this transcription factor are only poorly understood. We recently discovered multiple roles of Ttk in the development of the tracheal system on the morphogenetic level. Here, we sought to identify some of the underlying genetic components that are responsible for the tracheal phenotypes of Ttk mutants. We therefore profiled gene expression changes after Ttk loss- and gain-of-function in whole embryos and cell populations enriched for tracheal cells. The analysis of the transcriptomes revealed widespread changes in gene expression. Interestingly, one of the most prominent gene classes that showed significant opposing responses to loss- and gain-of-function was annotated with functions in chitin metabolism, along with additional genes that are linked to cellular responses, which are impaired in ttk mutants. The expression changes of these genes were validated by quantitative real-time PCR and further functional analysis of these candidate genes and other genes also expected to control tracheal tube size revealed at least a partial explanation of Ttk's role in tube size regulation. The computational analysis of our tissue-specific gene expression data highlighted the sensitivity of the approach and revealed an interesting set of novel putatively tracheal genes

Essential Role of Chromatin Remodeling Protein Bptf in Early Mouse Embryos and Embryonic Stem Cells

We have characterized the biological functions of the chromatin remodeling protein Bptf (Bromodomain PHD-finger Transcription Factor), the largest subunit of NURF (Nucleosome Remodeling Factor) in a mammal. Bptf mutants manifest growth defects at the post-implantation stage and are reabsorbed by E8.5. Histological analyses of lineage markers show that Bptf−/− embryos implant but fail to establish a functional distal visceral endoderm. Microarray analysis at early stages of differentiation has identified Bptf-dependent gene targets including homeobox transcriptions factors and genes essential for the development of ectoderm, mesoderm, and both definitive and visceral endoderm. Differentiation of Bptf−/− embryonic stem cell lines into embryoid bodies revealed its requirement for development of mesoderm, endoderm, and ectoderm tissue lineages, and uncovered many genes whose activation or repression are Bptf-dependent. We also provide functional and physical links between the Bptf-containing NURF complex and the Smad transcription factors. These results suggest that Bptf may co-regulate some gene targets of this pathway, which is essential for establishment of the visceral endoderm. We conclude that Bptf likely regulates genes and signaling pathways essential for the development of key tissues of the early mouse embryo

The MYST-Containing Protein Chameau Is Required for Proper Sensory Organ Specification during Drosophila Thorax Morphogenesis

The adult thorax of Drosophila melanogaster is covered by a stereotyped pattern of mechanosensory bristles called macrochaetes. Here, we report that the MYST containing protein Chameau (Chm) contributes to the establishment of this pattern in the most dorsal part of the thorax. Chm mutant pupae present extra-dorsocentral (DC) and scutellar (SC) macrochaetes, but a normal number of the other macrochaetes. We provide evidences that chm restricts the singling out of sensory organ precursors from proneural clusters and genetically interacts with transcriptional regulators involved in the regulation of achaete and scute in the DC and SC proneural cluster. This function of chm likely relies on chromatin structure regulation since a protein with a mutation in the conserved catalytic site fails to rescue the formation of supernumerary DC and SC bristles in chm mutant flies. This is further supported by the finding that mutations in genes encoding chromatin modifiers and remodeling factors, including Polycomb group (PcG) and Trithorax group (TrxG) members, dominantly modulate the penetrance of chm extra bristle phenotype. These data support a critical role for chromatin structure modulation in the establishment of the stereotyped sensory bristle pattern in the fly thorax

Whole-genome sequencing for an enhanced understanding of genetic variation among South Africans

The Southern African Human Genome Programme is a national initiative that aspires to unlock the unique genetic character of southern African populations for a better understanding of human genetic diversity. In this pilot study the Southern African Human Genome Programme characterizes the genomes of 24 individuals (8 Coloured and 16 black southeastern Bantu-speakers) using deep whole-genome sequencing. A total of ~16 million unique variants are identified. Despite the shallow time depth since divergence between the two main southeastern Bantu-speaking groups (Nguni and Sotho-Tswana), principal component analysis and structure analysis reveal significant (p < 10−6) differentiation, and FST analysis identifies regions with high divergence. The Coloured individuals show evidence of varying proportions of admixture with Khoesan, Bantu-speakers, Europeans, and populations from the Indian sub-continent. Whole-genome sequencing data reveal extensive genomic diversity, increasing our understanding of the complex and region-specific history of African populations and highlighting its potential impact on biomedical research and genetic susceptibility to disease