Mineral Policy Issues in the Context of Export and Domestic Use of Iron Ore in India

This study examines the utilization of iron ore in India. It takes into account the significant reserves of iron ore in India and allays fears that the country's steel industry will run out of iron ore resources if exports continue at the current level. On the contrary, it says that exports are necessary to maintain a structural balance in the market between production and consumption of lumps and fines as nearly 80% of exported ores are fines which are not adequately used in India. This study also highlights the specific problems of the Goa/Radi region. It examines the bilateral agreements with countries like Japan and Korea as well. The study says that the size of mineral resources is a dynamic concept and depends on exploratory efforts, which have not been enough in India due to lack of investments. It recommends on the basis of international experience that increased investment in the mineral sector, especially in exploration, will lead to new reserves and resources.Export of Iron Ore, Mineral Policy, Domestic Consumption, Steel Industry

Magnetotransport properties of a magnetically modulated two-dimensional electron gas with the spin-orbit interaction

We study the electrical transport properties of a two-dimensional electron gas with the Rashba spin-orbit interaction in presence of a constant perpendicular magnetic field $(B_0 \hat z)$ which is weakly modulated by ${\bf B_1} = B_1 \cos (q x) \hat z$, where $B_1 \ll B_0$ and $q = 2 \pi/a$ with $a$ is the modulation period. We obtain the analytical expressions of the diffusive conductivities for spin-up and spin-down electrons. The conductivities for spin-up and spin-down electrons oscillate with different frequencies and produce beating patterns in the amplitude of the Weiss and Shubnikov-de Haas oscillations. We show that the Rashba strength can be determined by analyzing the beating pattern in the Weiss oscillation. We find a simple equation which determines the Rashba spin-orbit interaction strength if the number of Weiss oscillations between any two successive nodes is known from the experiment. We compare our results with the electrically modulated 2DEG with the Rashba interaction. For completeness, we also study the beating pattern formation in the collisional and the Hall conductivities.Comment: 11 pages, 5 figures, re-written with new result

Designing of highly effective complementary and mismatch siRNAs for silencing a gene

In past, numerous methods have been developed for predicting efficacy of short interfering RNA (siRNA). However these methods have been developed for predicting efficacy of fully complementary siRNA against a gene. Best of author's knowledge no method has been developed for predicting efficacy of mismatch siRNA against a gene. In this study, a systematic attempt has been made to identify highly effective complementary as well as mismatch siRNAs for silencing a gene. Support vector machine (SVM) based models have been developed for predicting efficacy of siRNAs using composition, binary and hybrid pattern siRNAs. We achieved maximum correlation 0.67 between predicted and actual efficacy of siRNAs using hybrid model. All models were trained and tested on a dataset of 2182 siRNAs and performance was evaluated using five-fold cross validation techniques. The performance of our method desiRm is comparable to other well-known methods. In this study, first time attempt has been made to design mutant siRNAs (mismatch siRNAs). In this approach we mutated a given siRNA on all possible sites/positions with all possible nucleotides. Efficacy of each mutated siRNA is predicted using our method desiRm. It is well known from literature that mismatches between siRNA and target affects the silencing efficacy. Thus we have incorporated the rules derived from base mismatches experimental data to find out over all efficacy of mutated or mismatch siRNAs. Finally we developed a webserver, desiRm (http://www.imtech.res.in/raghava/desirm/) for designing highly effective siRNA for silencing a gene. This tool will be helpful to design siRNA to degrade disease isoform of heterozygous single nucleotide polymorphism gene without depleting the wild type protein

IN VITRO ANTI-INFLAMMATORY AND HEPATOPROTECTIVE ACTIVITY OF TURMESAC®

Objective: In this study, we investigated the hepatoprotective activity of Turmesac® on Human liver cells (HepG2 cell line) and anti-inflammatory effect on Murine macrophages (Raw 264.7 cell line) by flow Cytometry. Methods: Cell viability of HepG2 and Raw 264.7 cells determined by the MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] assay to identify a non-cytotoxic concentration of Turmesac® for the respective cell lines after 24 h exposure period. Further hepatoprotective effect of Turmesac® was performed in H2O2 treated liver cells using H2DCF-DA staining by flow cytometry. The anti-inflammatory potency of Turmesac® was evaluated in Lipopolysaccharide (LPS 2µg/ml) stimulated Murine Raw 264.7 macrophages by measuring the relative fluorescence intensity of 2 cytokines, Interleukin-8(IL-8) and (Interleukin-12) IL-12 by flow cytometric analysis. Results: Turmesac® concentrations of less than 50μg/ml did not show significant cytotoxicity on both HepG2 and Raw 264.7, cell lines following the treatment period of 24 h and selected 50μg/ml as the optimum concentration for hepatoprotective and anti-inflammatory models. The reactive oxygen species (ROS) study revealed that Turmesac® (50μg/ml) effectively suppressed the H2DCF-DA expression in HepG2 cells. Secondly, Turmesac® significantly suppressed the anti-inflammatory cytokine expressions of IL-8 and IL-12 in LPS pre-stimulated cells categorising as a potentially potent anti-inflammatory drug. The mean fluorescence intensity percentage of IL-8 is control 8.86, LPS 50.49, Turmesac® 19.63 and IL12 is control 10.41, LPS 68.94, and Turmesac® 15.79 respectively. Conclusion: This study highlighted that Turmesac® could be considered as a promising hepatoprotective and anti-inflammatory compound and a therapeutic agent in curing liver-related and inflammation-related diseases

Prediction of polyadenylation signals in human DNA sequences using nucleotide frequencies

The polyadenylation signal plays a key role in determining the site for addition of a polyadenylated tail to nascent mRNA and its mutation(s) are reported in many diseases. Thus, identifying poly(A) sites is important for understanding the regulation and stability of mRNA. In this study, Support Vector Machine (SVM) models have been developed for predicting poly(A) signals in a DNA sequence using 100 nucleotides, each upstream and downstream of this signal. Here, we introduced a novel split nucleotide frequency technique, and the models thus developed achieved maximum Matthews correlation coefficients (MCC) of 0.58, 0.69, 0.70 and 0.69 using mononucleotide, dinucleotide, trinucleotide, and tetranucleotide frequencies, respectively. Finally, a hybrid model developed using a combination of dinucleotide, 2nd order dinucleotide and tetranucleotide frequencies, achieved a maximum MCC of 0.72. Moreover, for independent datasets this model achieved a precision ranging from 75.8-95.7% with a sensitivity of 57%, which is better than any other known methods

Corporate policy on HIV/AIDS intervention : a policy analysis.

Thesis (M.A.)-University of Natal, Pietermaritzburg, 2001.This study is concerned with corporate policy on IllV/AIDS. This was investigated by speaking to key-informants from fifteen enterprises in KwaZulu Natal. They were asked about their policies and programmes and what they had put in place to combat this epidemic. The rational choice model was used as a framework for analysis ofthe policies. This model is discussed in the first part ofthe study and was chosen as it seems to reflect the dominant policy outlook in South Africa and may shape the way that organisations .respond. The second part of the project is the report and discussion of the findings. It is a presentation ofthe responses given by the key informants regarding their perceptions and understanding of the problem of IllV/AIDS as well as the policies .of their companies regarding the same. Mostofthe companies in the study did not have policies specific to. IDV/AIDS. Some had general guidelines and treated HIV/AIDS as any major illness. There seemed to be denial, especially among the management, of the seriousness of the disease despite evidence ofits significant impact within the various organisations. There were few to no resources set aside formv/AIDS programmes and interventions and this seems important in defining the IllV/AIDS problem as one of the future rather than the present In the third part of this project, the theoretical framework and the findings were linked. There was an attempt to answer the question ofhow rational the policy process is within the companies in the study and .whether the responses of these organisations can be understood in the context ofthe rational choice model. It seems that this model does aid in understanding of the policy process when there is a realisation· that it interacts with other human mctors to create what we observe

Detection of crystal structure of chemically-deposited copper selenide thin films

A low cost Chemical Bath Deposition (CBD) system has been developed in our laboratory for the preparation of copper selenide thin film. Good quality thin films of smooth surface of copper selenide thin films of compositions Cu2-xSe (x = 0.1–0.5) and Cu3Se2 were deposited using sodium selenosulfate as a source of selenide ions. Crystal structure of copper selenide (Cu1.8Se and Cu3Se2) thin films has been identified by X-ray diffraction (XRD) method. When the film is annealed at 250ºC in air, the phases of Cu1.8Se and Cu3Se2 become crystalline, with structures of cubic (berzelianite) and tetragonal, respectively, whereas the as-deposited film was found to be disorder. The crystallinity is very low in as-deposited samples, which improves on annealing in air at 250ºC. The grain size of the as-deposited samples was very small, which was increased about 30% owing to annealing in air at 250ºC.Author Affiliation: Al-Mamun, S H Firoz and A B M O Islam 1.Department of Physics, University of Dhaka, Dhaka-1000, Bangladesh 2.Institute of Glass and Ceramic Research and Testing Bangladesh Council for Scientific and Industrial Research (BCSIR), Dhaka-1205, Bangladesh E-mail : [email protected] of Physics, University of Dhaka, Dhaka-1000, Bangladesh 2.Institute of Glass and Ceramic Research and Testing Bangladesh Council for Scientific and Industrial Research (BCSIR), Dhaka-1205, Banglades

Zero-field spin splitting in a two-dimensional electron gas with the spin-orbit interaction revisited

We consider a two-dimensional electron gas (2DEG) with the Rashba spin-orbit interaction (SOI) in presence of a perpendicular magnetic field. We derive analytical expressions of the density of states (DOS) of a 2DEG with the Rashba SOI in presence of magnetic field by using the Green's function technique. The DOS allows us to obtain the analytical expressions of the magnetoconductivities for spin-up and spin-down electrons. The conductivities for spin-up and spin-down electrons oscillate with different frequencies and gives rise to the beating patterns in the amplitude of the Shubnikov de Hass (SdH) oscillations. We find a simple equation which determines the zero-field spin splitting energy if the magnetic field corresponding to any beat node is known from the experiment. Our analytical results reproduce well the experimentally observed non-periodic beating patterns, number of oscillations between two successive nodes and the measured zero-field spin splitting energy.Comment: 5 pages, 2 figure

Correlation between reflectivity and photoluminescent properties of porous silicon films

Porous silicon (PS) layers were formed on p-type, oriented, 1–5 Ω cm resistivity Cz silicon wafers by electrochemical etching in an HF:C2H5OH (1:2 by volume) electrolyte at room temperature at a constant current density 20 mA/cm2. The etching duration was varied to achieve PS layers of different morphologies and thicknesses. Both the photoluminescence (PL) and the total diffused reflectivity spectra of the PS layers were measured. It was found that for the PS layers grown for etching durations of less than 90 s the PL emission is insignificant and reflectivity is quite low. Such PS layers can be used as antireflection coatings (ARC) on solar cells. The PS layers formed for etching durations greater than 90 s show a significant PL emission in 500–800 nm range with peak lying in 630–660 nm wavelength range. When etching duration increases from 90 s to 8 min the PL intensity increases and the PL peak shows a blue shift. With further increase in etching duration the PL intensity decreases and PL peak shows a red shift. The reflectivity of the photoluminescent layers increases with etching duration showing a highest value for a sample grown for 8 min. Further increase in etching duration up to 20 min the reflectivity decreases and then increases. Striking observation is that both the PL emission intensity and reflectivity in the wavelength range of 550–800 nm are maximum for the PS layer grown for the etching duration of 8 min