Podcasts about variscan

In this episode Barry chats to Stewart Dickson, Managing Director & CEO at Variscan Mines (ASX:VAR)

Today we speak to Stewart Dickson, CEO - Variscan Mines Limited, a natural resources company focused on the development of high-impact base-metal projects who currently have projects in Australia, Spain and Chile. Stewart’s journey into mining isn’t the norm as he started off in the military so I was curious to know and understand how he got into the mining industry and learn how someone with a non-technical mining background can develop a career in the mining industry.     In this episode, we chat about what qualities are needed from people that are not from a mining background. We talk about the skills and experience Stewart has bought to the mining industry and his emphasis on teams, trust and cooperation which are so important in management today. We also cover risk and opportunity working in developing countries.     KEY TAKEAWAYS  An unconventional pathway  My career in the military provided me with a great foundation for working in the mining industry.  There are some common traits between the oil and gas mining industries and the military that allowed me to empathise with management teams.  These traits include being able to face up to a challenge whether technical, physical, political, intellectual and a willingness and desire to go out and achieve an objective or corporate intent irrespective of the circumstances.    It’s the will to win mentality and the ability and desire to see a project through from inception to completion.  Being non-technical  The nature of the industry, it’s multidisciplinary and complex, requires a comprehensive approach to situations, projects and opportunities.  Non-technical people benefit from not thinking in a particular way or are rigid because of expertise in a particular area.  You need to have the right people with the right skills in the right role  The role of the senior leader is to bring people together effectively to win or lose together as a team.  Good teams  You use the enriched experiences of those around you and what binds it together is clarity of intent, the unifying purpose needs to come from the leadership. Without commitment from leadership, the team will struggle to operate.  The key is clarity of intent everybody in the organisation knows what they are trying to achieve.  They know that whatever actions they take they are directed towards achieving the plan or purpose.  Leadership style  There is no right way or right pathway you have to be comfortable of your own strengths and weaknesses  There is no right way and if you try to be someone you are not it will not stand up in a stressful or complex situation  We are in a  hyper-connected world there will be times where you are looking at a physical situation with virtual aspects as well.  Trust your team you’ve hired and nurtured them.  If you apply this most of the time people pay you back hugely.    BEST MOMENTS  ‘It’s looking at situations in a 360 way’  ‘You need to want to win with personal resilience and robustness along with the fortitude to deal with what comes in front of you’  ‘In mining it’s all about the prevent phase - your social licence and engagement’    VALUABLE RESOURCES  The Dig Deep Mining Podcast  Variscan Mining website      ABOUT THE HOST  Rob Tyson  Rob Tyson is an established recruiter in the mining and quarrying sector and decided to produce the “Dig Deep” The Mining Podcast to provide valuable and informative content around the mining industry. He has a passion and desire to promote the industry and the podcast aims to offer the mining community insight to people’s experiences and careers covering any mining discipline, giving the listeners helpful advice and guidance on industry topics.  Rob is the Founder and Director of Mining International Ltd, a leading global recruitment and headhunting consultancy based in the UK specialising in all areas of mining across the globe from the first world to third world countries from Africa, Europe, Middle East, Asia and Australia. We source, headhunt and discover new and top talent through a targeted approach and search methodology and have a proven track record in sourcing and positioning exceptional candidates into our clients’ organisation in any mining discipline or level. Mining International provides a transparent, informative and trusted consultancy service to our candidates and clients to help them develop their careers and business goals and objectives in this ever-changing marketplace.     CONTACT METHOD  Email Rob at rob@mining-international.org  Rob’s LinkedIn          Mining InternationalOfficial Website       Mining International’sTwitter       Mining International’sFacebook

This work is dedicated to studying natural variation in D. melanogaster at the DNA sequence and gene expression level. In addition I present a new version of the DNA polymorphism analysis program VariScan, which includes significant improvements. In CHAPTER 1 I describe a genome scan of single nucleotide polymorphism in two natural D. melanogaster populations (from Africa and Europe) on the third chromosome. Together with polymorphism data previously published for the X chromosome of the same populations, this allows a comparative study of the polymorphism patterns of the X chromosome and an autosome. The frequency spectrum of mutations and the patterns of linkage disequilibrium are investigated. The observed patterns indicate that there is a significant difference in the behavior of the two chromosomes, as has already been suggested by previous studies. To uncover the reasons for this a coalescent based maximum likelihood method is applied that incorporates the effects of demographic history and unequal sex ratios. For the African population the differential behavior of the chromosomes can be explained by its demographic history and an excess of females. In Europe, a population bottleneck and an excess of males alone cannot explain the patterns we observe. The additional action of positive selection in this population is proposed as a possible explanation. In CHAPTER 2 I investigate the variation in gene expression of the two aforementioned populations. Whole-genome microarrays are used to study levels of expression for 88% of all known genes in eight adult males from both populations. The observed levels of expression variation are equal in Africa and Europe, despite the fact that DNA sequence variation is much higher in Africa. This is evidence for the action of stabilizing selection governing levels of expression polymorphism. Supporting this view, genes involved in many different functions, and are therefore on strong selective constraint, show less variation than do genes with only few functions. The experimental design allows the search for genes which differ in their expression patterns between Europe and Africa and might therefore have undergone adaptive evolution. Detected candidates include genes putatively involved in insecticide resistance and food choice. Surprisingly, many genes over-expressed in Africa are involved in the formation and function of the flying apparatus. In CHAPTER 3 I present version 2 of the program VariScan. This program was designed to analyse patterns of DNA sequence polymorphism on a chromosomal scale. The functionality of the core analysis tool, the wavelet decomposition, is described. In addition, multiple improvements to the previous version are presented. The program now supports the “pairwise deletion” option. This is essential for analysing data at the chromosome scale, since such data often contains incomplete information. It is now possible to add outgroup information, which allows the calculation of additional statistics. Furthermore, the separate analysis of different predefined chromosomal regions is added as an option. To increase the user friendliness, a graphical user interface is now included as part of the software package. Finally, VariScan is applied to published and computer-generated data and the ability of the wavelet-based analysis to uncover chromosomal regions with interesting DNA polymorphism patterns is demonstrated.

Background: DNA sequence polymorphisms analysis can provide valuable information on the evolutionary forces shaping nucleotide variation, and provides an insight into the functional significance of genomic regions. The recent ongoing genome projects will radically improve our capabilities to detect specific genomic regions shaped by natural selection. Current available methods and software, however, are unsatisfactory for such genome-wide analysis. Results: We have developed methods for the analysis of DNA sequence polymorphisms at the genome-wide scale. These methods, which have been tested on a coalescent-simulated and actual data files from mouse and human, have been implemented in the VariScan software package version 2.0. Additionally, we have also incorporated a graphical-user interface. The main features of this software are: i) exhaustive population-genetic analyses including those based on the coalescent theory; ii) analysis adapted to the shallow data generated by the high-throughput genome projects; iii) use of genome annotations to conduct a comprehensive analyses separately for different functional regions; iv) identification of relevant genomic regions by the sliding-window and wavelet-multiresolution approaches; v) visualization of the results integrated with current genome annotations in commonly available genome browsers. Conclusion: VariScan is a powerful and flexible suite of software for the analysis of DNA polymorphisms. The current version implements new algorithms, methods, and capabilities, providing an important tool for an exhaustive exploratory analysis of genome-wide DNA polymorphism data.

Tue, 13 Jul 2004 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/2413/ https://edoc.ub.uni-muenchen.de/2413/1/Schaetz_Michael.pdf Schätz, Michael ddc:550, ddc:500, Fakultä

The present work combines palaeomagnetic and rock magnetic methods with clay mineralogy, isotope geochemistry of clay minerals and trace element geochemistry of Fe-oxide leachates to study remagnetised sedimentary rocks from Palaeozoic outcrops in Middle and Eastern Europe. Three areas were selected (NE Rhenish Massif, Barrandian and Holy Cross Mountains), where the causes of Late Palaeozoic remagnetisations are yet unclear. The results yield important implications for the processes and mechanisms responsible for the remagnetisations in the areas studied. NE Rhenish Massif: A Late Carboniferous remagnetisation (component B) is identified in Late Palaeozoic carbonate and clastic rocks from the NE Rhenish Massif. Three individual incremental regional fold tests across the area show a unique and distinctive variation in timing of remagnetisation relative to the age of folding. The remagnetisation is postfolding in the South and of synfolding origin in the North of the area. Consequently, the timing and the duration of the remagnetisation event is constrained by the age of folding, which varies throughout the area and reflects a northward migration of the deformation front during 325 Ma to 300 Ma. Comparison of the resulting palaeolatitude of the NE Rhenish Massif with the palaeolatitudinal drift history for the region yields an estimate for the age of remagnetisation of ca. 315 - 300 Ma, which is in good agreement with the age of deformation. The concordance of the magnetic palaeoinclinations obtained from the entire area indicates that the rocks were remagnetised during a relatively short period of only a few My. The thermal stability of the remanence up to 550°C the comparably low palaeotemperatures in the studied region and the short duration of the remagnetisation event favour a chemical remagnetisation process. Rock magnetic experiments reveal a complex magnetomineralogy of the remagnetised Palaeozoic sediments from the NE Rhenish Massif. The dominant carrier of the Carboniferous magnetisation component is magnetite, but pyrrhotite and hematite accompany magnetite as carrier of the NRM in some grey carbonates and red sandstones or red nodular limestones, respectively. The hysteresis ratios, magnetic viscosity and low temperature behaviour of the carbonate rocks give strong evidence for the presence of very fine grained (superparamagnetic) magnetic minerals. This material is also thought to be responsible for similar rock magnetic properties of siliciclastic rocks. This interpretation, however, is not unique for the siliciclastic rocks, due to the predominance of detrital MD magnetite and the high amount of paramagnetic material. The hysteresis ratios from medium to coarse grained rocks and reef carbonates fall in or close to the fields of MD magnetite and remagnetised carbonates, respectively. The fine grained clastic rocks (siltstones) and limestone turbidites have intermediate hysteresis properties. This implies the presence of very fine grained magnetic material in all lithologies of the NE Rhenish Massif, which is indicative for authigenic growth of magnetic minerals and formation of a CRM. However, the magnetic fingerprint of SP grains gets increasingly disguised with increasing amount of detrital MD magnetite in clastic rocks. K-Ar dating of

U-Pb-SHRIMP dating of zircons, zircon morphology, geochemistry and isotopic data of metamagmatites from the Bayerischer Wald (Germany) reveal a complex evolution of this section of the Moldanubian Zone exposed in the western Bohemian Massif of the central European Variscan belt. In the south-western part of the Bayerischer Wald Upper Vendian magmatism is constrained by SHRIMP ages of 555 ± 12, 549 ± 7 and 549 ± 6 Ma from metarhyolites and a metabasite. Inherited zircon cores were not observed. Zircon overgrowths yielding pooled ages of 316 ± 10 and 319 ± 5 Ma provide evidence for Variscan metamorphic zircon growth; cathodoluminescence imaging reveals a two-stage metamorphic overprint. In contrast, Lower Ordovician magmatism and anatexis are documented in the north-eastern parts of the Bayerischer Wald by metagranitoids (480 ± 6, 486 ± 7 Ma) and a leucosome (491 to 457 Ma). Inherited zircon cores are found in Lower Ordovician metamagmatites indicating a Palaeoproterozoic-Archaean (2.70, 2.02 Ga) source region, presumably of Gondwana affinity (West African craton), and documenting Cadomian magmatism (>615 to 560 Ma). Upper Vendian magmatism is assumed at an active continental margin with ensialic back-arc development (εNd(t) –4.58 to +1.22). An active continental margin setting, possibly with some lateral variation (accretion/collision) is envisaged for the Lower Ordovician producing granitoids, rhyolites, leucosomes (εNd(t) -0.5 to -6.27) and andesites. A tentative palaeogeographic reconstruction puts the "Bayerischer Wald" in a close relationship with the Habach terrane (proto-Alps), as the "eastern" extension of terranes of the northern Gondwana margin.