3,899 research outputs found

    On the Variation of Grain Density with Specific Energy Loss in Nuclear Emulsions

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    Receding the entrainment of concomitant Ultrafines by MGS in Lead Concentrate of Rajpura - Dariba Concentrator

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    Due to the fine dissemination and complex mineralogy the Rajpu ra-Dariba (RD) lead --inc ore poses special problems in concentration by corrventional froth flotation. In order to achieve the desired metallurgical results 'Multi Gravity Separator, a twin drum system, has recently been installed in the lead circuit of RD concentrator. Open and closed trial tests were conducted, without sacrificing the economic metal tt•ith substantial abatement of ultrafine card fine srliceuus and graphite matter in lead concentrate. The metallurgical alludes achieved are (i) over 85% -400 mesh fines are separated in the form of MGS tails whereas 53% -400 mesh are obtained in MGS concentrate from the feed(lead rougher concentrate) 77% -400 mesh with 52% Pb, I% Gr. C and 2.5% ISM in respective Wt. %distribution i.e., 47.3 and 3, (ii) tails are characterised br- >93% ultrafine of <20 microns particles encompass 21 % Pb, 8% Gr: C and 39% ISM with respective Wt. % distribution i.e., 32. 93, 83% in -400 mesh fr-action, resulting in effective rejection of Gr. C and ISM, (iii)conventional lead concentrate consists of 28% +400 mesh material only with all the assorted fines and ultrafines. Mine ralogically, it is established that composite bigger particles of sulphide gangue and graphite are the main contributor. for silica and graphite in MGS concentrate. Over 39% by vol. fines are alienated as MGS tails, in the form of free sulphide, gangue and graphite minerals. Installation of MGS in lead circuit, confirms the significant reduction of Gr:C and ISM in particular to high GMS_feed rnix in lead concentrate in comparison to lead concentrate by conventional route

    Analysis of Observed Grain Density in Nuclear Emulsions

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    Palliation of advanced/metastatic carcinoma esophagus with radiotherapy

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    Background: Esophageal carcinoma carries an overall poor prognosis. Most patients present with lo¬cally advanced, unresectable or metastatic disease. The main objective in advanced disease is the palliation of dysphagia. Treatment options include surgery (bypass, resection), laser, stent placement, external beam radiotherapy (EBRT), brachytherapy and systemic chemotherapy. We have focused on our experience with EBRT followed by brachytherapy.Methods: From January 2013 to December 2014, 29 patients of advanced/metastatic esophageal cancer were treated by HDR Brachytherapy following EBRT. All patients received 2# of 5Gy HDR brachytherapy. EBRT was 40Gy/20# (18 patients) and 36Gy/12# (11 patients). Disease remission and relief of dysphagia along with toxicity assessment were carried out at 1, 3 and 6 months after completion of treatment.Results: Evaluation at 1 month after brachytherapy showed complete remission (CR) of the disease in 6 patients, partial remission (PR) in 17 patients and no remission (NR) in 6. Overall improvement in swallowing status was seen in 22(75.86%) patients. 7 patients showed no improvement and 1 reported worsening of dysphagia score at 1 month after ILRT. The improvement in swallowing was maintained by 55.17% of patients at 6 months. Strictures had developed in 5 patients, ulceration in 3 patients and fistula in 1.Conclusions: A combination of EBRT and HDR brachytherapy affords effective palliation in advanced esophageal cancer with acceptable toxicity.

    Role Of Social & Psychological Factors In Drug Default In Patients Of Pulmonary Tuberculosis

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    Research Problem: What is the influence of social and psychological factors on drug default in patients of pul­monary tuberculosis? Objective: To assess the role of social and psychological factors in drug default in patients of pulmonary tubercu­losis. Study Design: Hospital - based study by questionnaire method Setting and Participants: Patients of pulmonary tubercu­losis attending Out Patient Department of Tuberculosis and Respiratory Diseases, J.N. Medical College Hospital, A.M.U., Aligarh. Sample Size: 136 defaulters and 86 treated cases of pulmonary tuberculosis. Study Variables: Social factors, psychological factors, drug default and pulmonary tuberculosis. Outcome Variables: Association of social and psycho­logical factors with drug default in pulmonary tuberculo­sis patients. Statistical Analysis: By chi - square test and significance at 5% level. Result: Important social factors influencing drug default were joint family (74.27%), lack of money (22.06%) and uncooperative family (11.7%). Psychiatric morbidity among defaulters was significantly high (68.39%). Conclusion: Patient compliance depends on many psy­chological (e.g. psychiatric morbidity, type of personal­ity), and sociological,factors (including economic status of patient, nature of family, its environment, interaction between patient and doctor and patient's own attitude and idea about his disease). Age, sex, residence, religion and education did not show any significant contribution towards drug default

    Double Perovskite Sr2FeMoO6: A Potential Candidate for Room Temperature Magnetoresistance Device Applications

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    The family of double perovskites first received attention in the 1960s, but the discovery of low field magnetoresistnace (LFMR) and half metallicity of the Sr2FeMoO6 (SFMO) compound was made by Kobayashi et al. in 1998. A fully spin polarized half-metal SFMO (Tc > 400) with excellent magnetoresistance response relatively at small applied fields and high temperatures makes SFMO an ideal candidate for room temperature spintronics applications. Primarily, most of the research work on double perovskites SFMO has been focused on bulk ceramic samples and aimed to understand their structural, magnetic, and magnetotransport properties, along with correlation among them. A material such as SFMO that exhibits a large decrease in resistivity and magnetically order well above room temperature is necessary for the advancement of spintronic devices. If the bulk properties observed could be reproduced in thin films, industrially produced SFMO-based spintronic devices could become a reality. Therefore, the purpose of this chapter is to present the detailed background and descriptions of the double perovskite Sr2FeMoO6 (SFMO) thin films and heterostructures with main emphasis to improve or achieve room temperature magnetoresistance properties especially for room temperature magnetoresistive device applications

    Mapping of Thar Desert Grasslands Using High Resolution Carto-Data (A Case Study of Jodhpur District)

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    The spatio-temporal condition and trend of grasslands in India at village-level is still not known completely. Historical and contemporary monitoring and assessment protocols are primarily based on the wisdom, knowledge and experience of village-level revenue officer (patwari) which is just significant from the statistical point of view. Contrastingly, such grassland areas are considered to be of high priority by government authorities for the long-term conservation of biodiversity. Protection, development and sustainable use of grasslands are very important for the rural economy and livestock. The major grasslands now survive west of isohyets 200 to 250 mm rainfall where livestock population is more than human beings. Animal husbandry plays such an important role in the lifestyle and economics of the inhabitants, scientific management of the grasslands, on which the animals depend for nourishment, is totally neglected. Pastoralism has coexisted within dry lands for decades. The constant pressure from an increasing human population and anthropogenic activities, particularly mining, has caused considerable damage to this unique desert grassland ecosystem. Several important grasslands have been converted to agricultural fields and the pressure to convert more grassland into such uses is mounting. Area under grasslands in the Jodhpur district has declined very sharply. It was 6.4% in 1976 (Sen, 1978) but has been reduced to \u3c 1.5% of the district area. Grasslands are one of the important classes of land use mapping exercise. The aim of the present project was to identify and map all grasslands and grazing areas in the Jodhpur district using spectral signatures of 2012-13 high resolution satellite data of Cartosat LISS-IV plus PAN merged and compare with 1976-77 and 2005-06 data. There is a need to sustain and conserve grasslands at grassroots level because these are the important life-supporting mechanism of the dry region. There is an immediate scope for the spatial and temporal scale dependence of assessment tools for grassland monitoring and undertaking research at village-to district-scales to incorporate geographic information systems and satellite remote sensing data, as well as new ecological concepts from landscape ecology and complex systems science

    Evolution of the redox function in mammalian Apurinic/ apyrimidinic endonuclease

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    Human apurinic/apyrimidinic endonuclease (hApe1) encodes two important functional activities: an essential base excision repair (BER) activity and a redox activity that regulates expression of a number of genes through reduction of their transcription factors, AP-1, NFκB, HIF-1α, CREB, p53 and others. The BER function is highly conserved from prokaryotes (E. coli exonuclease III) to humans (hApe1). Here, we provide evidence supporting a redox function unique to mammalian Apes. An evolutionary analysis of Ape sequences reveals that, of the 7 Cys residues, Cys 93, 99, 208, 296, and 310 are conserved in both mammalian and non-mammalian vertebrate Apes, while Cys 65 is unique to mammalian Apes. In the zebrafish Ape (zApe), selected as the vertebrate sequence most distant from human, the residue equivalent to Cys 65 is Thr 58. The wild-type zApe enzyme was tested for redox activity in both in vitro EMSA and transactivation assays and found to be inactive, similar to C65A hApe1. Substitution of Thr 58 with Cys in zApe, however, resulted in a redox active enzyme, suggesting that a Cys residue in this position is indeed critical for redox function. In order to further probe differences between redox active and inactive enzymes, we have determined the crystal structures of vertebrate redox inactive enzymes, the C65A human Ape1 enzyme and the zApe enzyme at 1.9 and 2.3 Å, respectively. Our results provide new insights on the redox function and highlight a dramatic gain-of-function activity for Ape1 in mammals not found in non-mammalian vertebrates or lower organisms

    Clockwise rotation of the Brahmaputra Valley relative to India: Tectonic convergence in the eastern Himalaya, Naga Hills, and Shillong Plateau

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    GPS data reveal that the Brahmaputra Valley has broken from the Indian Plate and rotates clockwise relative to India about a point a few hundred kilometers west of the Shillong Plateau. The GPS velocity vectors define two distinct blocks separated by the Kopili fault upon which 2–3 mm/yr of dextral slip is observed: the Shillong block between longitudes 89 and 93°E rotating clockwise at 1.15°/Myr and the Assam block from 93.5°E to 97°E rotating at ≈1.13°/Myr. These two blocks are more than 120 km wide in a north‐south sense, but they extend locally a similar distance beneath the Himalaya and Tibet. A result of these rotations is that convergence across the Himalaya east of Sikkim decreases in velocity eastward from 18 to ≈12 mm/yr and convergence between the Shillong Plateau and Bangladesh across the Dauki fault increases from 3 mm/yr in the west to \u3e8 mm/yr in the east. This fast convergence rate is inconsistent with inferred geological uplift rates on the plateau (if a 45°N dip is assumed for the Dauki fault) unless clockwise rotation of the Shillong block has increased substantially in the past 4–8 Myr. Such acceleration is consistent with the reported recent slowing in the convergence rate across the Bhutan Himalaya. The current slip potential near Bhutan, based on present‐day convergence rates and assuming no great earthquake since 1713 A.D., is now ~5.4 m, similar to the slip reported from alluvial terraces that offsets across the Main Himalayan Thrust and sufficient to sustain a Mw ≥ 8.0 earthquake in this area
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