Possible Technical Upgradation Programme in CI Foundries

Indian Ferrous Foundry with Cupola as a melting unit dates back to the first decade of this century. The evolution of Indian Foundry and the distribution of organized and unorg-anized foundry units and their installed capacities are given in Fig. 1 and 2. Notice the following points : We may reach 4000 units by the turn of the century. With 15% of the total number of Foundries concentrated in West Bengal, the total share of installed capacity is around 40%

Treatment of Complex lead, Copper and Zinc sulfides

FOR the adoption of conventional methods for the recovery of lead , copper and zinc from the complex sulfide ores, it is essential that these be beneticiated to a high grade concentrate. The minerals present in such complex ores are often found in such close inter -growth that it is either difficult to obtain a suitable grade of the concentrate by physical methods or the recovery of metals in the respe-ctive concentrates is poor. For example, the zinc that finds its way to a copper concentrate is always discarded in the slag as a waste, while copper in a lead concentrate leads to serious smelting problems. In such cases the cost of production by conventional smelting process becomes unfavourable and new approaches to process the ores become more attractive

25 years of HIV-1 research – progress and perspectives

Twenty-five years after the discovery and isolation of the human immunodeficiency virus by French and American scientists, much progress has been made in basic research, clinical treatment, and public health prevention measures for acquired immunodeficiency syndrome. Here, we summarize, in brief, advances that have been achieved and provide some perspectives on future challenges

Thriving under Stress: Selective Translation of HIV-1 Structural Protein mRNA during Vpr-Mediated Impairment of eIF4E Translation Activity

Translation is a regulated process and is pivotal to proper cell growth and homeostasis. All retroviruses rely on the host translational machinery for viral protein synthesis and thus may be susceptible to its perturbation in response to stress, co-infection, and/or cell cycle arrest. HIV-1 infection arrests the cell cycle in the G2/M phase, potentially disrupting the regulation of host cell translation. In this study, we present evidence that HIV-1 infection downregulates translation in lymphocytes, attributable to the cell cycle arrest induced by the HIV-1 accessory protein Vpr. The molecular basis of the translation suppression is reduced accumulation of the active form of the translation initiation factor 4E (eIF4E). However, synthesis of viral structural proteins is sustained despite the general suppression of protein production. HIV-1 mRNA translation is sustained due to the distinct composition of the HIV-1 ribonucleoprotein complexes. RNA-coimmunoprecipitation assays determined that the HIV-1 unspliced and singly spliced transcripts are predominantly associated with nuclear cap binding protein 80 (CBP80) in contrast to completely-spliced viral and cellular mRNAs that are associated with eIF4E. The active translation of the nuclear cap binding complex (CBC)-bound viral mRNAs is demonstrated by ribosomal RNA profile analyses. Thus, our findings have uncovered that the maintenance of CBC association is a novel mechanism used by HIV-1 to bypass downregulation of eIF4E activity and sustain viral protein synthesis. We speculate that a subset of CBP80-bound cellular mRNAs contribute to recovery from significant cellular stress, including human retrovirus infection

Sexually dimorphic gene expression in the heart of mice and men

The prevalence and clinical manifestation of several cardiovascular diseases vary considerably with sex and age. Thus, a better understanding of the molecular basis of these differences may represent a starting point for an improved gender-specific medicine. Despite the fact that sex-specific differences have been observed in the cardiovascular system of humans and animal models, systematic analyses of sexual dimorphisms at the transcriptional level in the healthy heart are missing. Therefore we performed gene expression profiling on mouse and human cardiac samples of both sexes and young as well as aged individuals and verified our results for a subset of genes using real-time polymerase chain reaction in independent left ventricular samples. To tackle the question whether sex differences are evolutionarily conserved, we also compared sexually dimorphic genes between both species. We found that genes located on sex chromosomes were the most abundant ones among the sexually dimorphic genes. Male-specific expression of Y-linked genes was observed in mouse hearts as well as in the human myocardium (e.g. Ddx3y, Eif2s3y and Jarid1d). Higher expression levels of X-linked genes were detected in female mice for Xist, Timp1 and Car5b and XIST, EIF2S3X and GPM6B in women. Furthermore, genes on autosomal chromosomes encoding cytochromes of the monoxygenase family (e.g. Cyp2b10), carbonic anhydrases (e.g. Car2 and Car3) and natriuretic peptides (e.g. Nppb) were identified with sex- and/or age-specific expression levels. This study underlines the relevance of sex and age as modifiers of cardiac gene expression

HIV-1 Vpr Triggers Mitochondrial Destruction by Impairing Mfn2-Mediated ER-Mitochondria Interaction

Human immunodeficiency virus 1 (HIV-1) viral protein R (Vpr) has been shown to induce host cell death by increasing the permeability of mitochondrial outer membrane (MOM). The mechanism underlying the damage to the mitochondria by Vpr, however, is not clearly illustrated. In this study, Vpr that is introduced, via transient transfection or lentivirus infection, into the human embryonic kidney cell line HEK293, human CD4+ T lymphoblast cell line SupT1, or human primary CD4+ T cells serves as the model system to study the molecular mechanism of Vpr-mediated HIV-1 pathogenesis. The results show that Vpr injures MOM and causes a loss in membrane potential (MMP) by posttranscriptionally reducing the expression of mitofusin 2 (Mfn2) via VprBP-DDB1-CUL4A ubiquitin ligase complex, gradually weakening MOM, and increasing mitochondrial deformation. Vpr also markedly decreases cytoplasmic levels of dynamin-related protein 1 (DRP1) and increases bulging in mitochondria-associated membranes (MAM), the specific regions of endoplasmic reticulum (ER) which form physical contacts with the mitochondria. Overexpression of Mfn2 and DRP1 significantly decreased the loss of MMP and apoptotic cell death caused by Vpr. Furthermore, by employing time-lapse confocal fluorescence microscopy, we identify the transport of Vpr protein from the ER, via MAM to the mitochondria. Taken together, our results suggest that Vpr-mediated cellular damage may occur on an alternative protein transport pathway from the ER, via MAM to the mitochondria, which are modulated by Mfn2 and DRP1

Economic viability of bacterial leaching-A management research viewpoint

Bacterial leaching as an process to the other chemical leaching techniques in the extractive metallurgy of non-ferrous metals, particularly of copper, zinc and uranium, is under the development stage today. Data obtained by research institutes all over the world indicate a trend for its adoption in many instances because of its simplicity of operation, costs and its suitability in specific conditions. As an additional source of uranium from the earlier discarded dumps in Portugal as an alternative to the chemical leaching and technique for copper in Canada bacterial leaching has shown its value as a process in dealing with low grade ores as well as concentrates

Recovery of copper and zinc from scrap leaded brass

Pure electrolytic copper 99.98% has been recovered from leaded brass containing 60.02% copper, 39.30% zinc and 0.53% lead. Zinc is removed by distillation under vacuum at 1000°C and the residual metal cast into slabs to be used as anodes in electro-refining. The present investigation is confined to the recovery of copper and zinc of high purity from unserviceable leaded brass by partial removal of zinc by distillation under vacuum and subsequent electrolysis. Using the residual metal as anode, copper has first been deposited electrolytically at a current density of 2.16 amp/dm2 from an acid copper sulphate solution. From the acid solution electronegative metals like zinc and lead did not deposit. Lead remained in the anode slime as lead sulphate. After complete dissolution of the anode, copper was recovered from the bath using insoluble lead anodes. After complete removal of copper, zinc sulphate was left in the solution and it was purified and crystallised

Solvent extraction of gallium from Bayer Process liquor (Indal, Muri) using 7-alkyl-substituted-8-hydroxyquinoline (Kelex-100)

Abstract no availabl