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Pretoria, South Africa

Council of Scientific and Industrial Research established in 1942, is an autonomous body and India's largest research and development organisation, with 37 laboratories and 39 field stations or extension centres spread across the nation, with a collective staff of over 17,000. Although CSIR is mainly funded by the Ministry of Science and Technology, it operates as an autonomous body registered under the Registration of Societies Act of 1860.The research and development activities of CSIR includes various fields such as aerospace engineering, Structural engineering, ocean science, Life science, metallurgy, chemicals, mining, food, petroleum, leather, and environment. In December 2006, Director General Raghunath A. Mashelkar, retired following which M. K. Bhan took over the post, but he was relieved on 7 March 2007. After that T. Ramasami had the additional charge of Director General of CSIR until Samir K. Brahmachari was appointed as the Director General on 13 November 2007.In late 2007, the Minister of Science and Technology, Kapil Sibal admitted, in a Question Hour session of the Parliament, that CSIR has developed 1,376 technologies/knowledgebase during the last decade of 20th century. Wikipedia.

Ray S.S.,South African Council for Scientific and Industrial Research

This article describes the focused ion beam (FIB)-tomography as a high-resolution three-dimensional (3D) technique to study the morphology of polymer/clay nanocomposites. To establish the structure-property relationship of such composite material, it is very important to visualize the 3D-structure and distribution of clay particles in the polymer matrix. The sequential two-dimensional sectioning by FIB, followed by imaging of dispersed silicate layers using high-resolution scanning electron microscope, and computer reconstruction can show the degree of dispersion of silicate layers in 3D-space. © 2010 Elsevier Ltd. Source

Archibald S.,University of Witwatersrand | Archibald S.,South African Council for Scientific and Industrial Research
Philosophical Transactions of the Royal Society B: Biological Sciences

Human impacts on fire regimes accumulated slowly with the evolution of modern humans able to ignite fires and manipulate landscapes. Today, myriad voices aim to influence fire in grassy ecosystems to different ends, and this is complicated by a colonial past focused on suppressing fire and preventing human ignitions. Here, I reviewavailable evidence on the impacts of people on various fire characteristics such as the number and size of fires, fire intensity, fire frequency and seasonality of fire in African grassy ecosystems, with the intention of focusing the debate and identifying areas of uncertainty. Humans alter seasonal patterns of fire in grassy systems but tend to decrease total fire emissions: livestock have replaced fire as the dominant consumer in many parts of Africa, and fragmented landscapes reduce area burned. Humans alter the season and time of day when fires occur, with important implications for fire intensity, tree-grass dynamics and greenhouse gas (GHG) emissions. Late season fires are more common when fire is banned or illegal: these later fires are farmore intense butemit fewerGHGs. The types of fireswhich preserve human livelihoods and biodiversity are not always aligned with the goal of reducing GHG concentrations. Current fire management challenges therefore involve balancing the needs of a large rural population against national and global perspectives on the desirability of different types of fire, but this cannot happen unless the interests of all parties are equally represented. In the future, Africa is expected to urbanize and land use to intensify,whichwill imply different trajectories for the continent’s fire regimes. © 2016 The Author(s) Published by the Royal Society. All rights reserved. Source

Wellington K.W.,South African Council for Scientific and Industrial Research
RSC Advances

The non-communicable disease, cancer, is one of the major causes of death across the world and is forecast to increase by 75% to reach close to 25 million cases over the next two decades. Radiotherapy and surgical approaches have been unsuccessful in controlling the incidence of most cancers. The development of chemotherapeutic strategies involving novel small molecule antitumour agents has therefore been the focus area of cancer chemotherapy for several decades as another strategy to combat and control the incidence of cancer. Many natural products as well as several synthetic drugs have a naphthoquinone chromophore. The anticancer activities of naphthoquinones have been the focus of much research to discover novel anticancer agents. The naturally occurring 1,2-naphthoquinone-based compound, β-lapachone (ARQ 761), is currently being assessed for its anti-tumour activity against advanced solid tumours. This review describes the most recent applications of naphthoquinones and their derivatives in cancer drug discovery. The biology relevant to the design of novel naphthoquinone anticancer agents is also discussed. Furthermore, the discussion of the biology will contribute to understanding cancer as well as the applications of naphthoquinones as anticancer agents. This journal is © The Royal Society of Chemistry 2015. Source

Naidoo D.,South African Council for Scientific and Industrial Research
Nature Photonics

The angular momentum of light can be described by positions on a higher-order Poincaré sphere, where superpositions of spin and orbital angular momentum states give rise to laser beams that have many applications, from microscopy to materials processing. Many techniques exist to create such beams but none so far allow their creation at the source. Here we report on a new class of laser that is able to generate all states on the higher-order Poincaré sphere. We exploit geometric phase control inside a laser cavity to map polarization to orbital angular momentum, demonstrating that the orbital angular momentum degeneracy of a standard laser cavity may be broken, producing pure orbital angular momentum beams, and that generalized vector vortex beams may be created with high purity at the source. This work paves the way to new lasers for structured light based on intracavity geometric phase control. © 2016 Nature Publishing Group Source

Roux F.S.,South African Council for Scientific and Industrial Research
Optics Letters

Optical vortices are always created or annihilated as vortex dipoles-pairs with opposite topological charge. Here a quantity, consisting of the transverse first and second derivatives of the optical field, is derived with which one can distinguish between vortex dipole annihilation and creation events. Analytical and numerical examples are provided as a demonstration of the method. © 2013 Optical Society of America. Source

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