194 research outputs found

    Performance Evaluation and Experimental Studies on Metallised Gel Propellants

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    Metallised gel propellants offer higher specific impulse and volumetric loading, reduced vaporisation loss, spillage and slosh problems and easy storage in comparison to the conventional liquid propellants. Theoretical performance analysis of gel propellant containing Al in unsymmetrical dimethyl hydrazine-dinitrogen tetroxide (UDMH-N/sub 2/O/sub 4} system shows peak Isp (vacuum condition) of 316.7 s and 318.3 s at oxidiser/fuel (O/f) ratios of 1.5 and 1.0, respectively for 30 per cent and 40 per cent UDMH-Al gel propellants, under standard conditions. The effect of other parameters like area ratio and chamber pressure on performance has been brought out in view of mission oriented applications. Aluminium has been found to be a better choice over magnesium in metallised gel propellants. Experimental studies on UDMH gellation using propellant grade (15 micrometer)and pyrotechnic grade (1.5 micrometer)Al in 500g batch level show that gellant(methyl cellulose) concentration could be reduced by 50 percent using pyrotechnic grade Al. The pseudoplastic-thixotropic behaviour, flow rate through die holes, burst pressure tests and bulk density are studied. UDMH -25 to 30 per cent Al gels with both grades of Al are found to be stable, pseudoplastic (shear thinning) and thixotropic (time-dependent shear thinning), but their flow pattern through die holes differ in nature

    Diversity, Dynamics and Therapeutic Application of Clostridioides difficile Bacteriophages

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    Clostridioides difficile causes antibiotic-induced diarrhoea and pseudomembranous colitis in humans and animals. Current conventional treatment relies solely on antibiotics, but C. difficile infection (CDI) cases remain persistently high with concomitant increased recurrence often due to the emergence of antibiotic-resistant strains. Antibiotics used in treatment also induce gut microbial imbalance; therefore, novel therapeutics with improved target specificity are being investigated. Bacteriophages (phages) kill bacteria with precision, hence are alternative therapeutics for the targeted eradication of the pathogen. Here, we review current progress in C. difficile phage research. We discuss tested strategies of isolating C. difficile phages directly, and via enrichment methods from various sample types and through antibiotic induction to mediate prophage release. We also summarise phenotypic phage data that reveal their morphological, genetic diversity, and various ways they impact their host physiology and pathogenicity during infection and lysogeny. Furthermore, we describe the therapeutic development of phages through efficacy testing in different in vitro, ex vivo and in vivo infection models. We also discuss genetic modification of phages to prevent horizontal gene transfer and improve lysis efficacy and formulation to enhance stability and delivery of the phages. The goal of this review is to provide a more in-depth understanding of C. difficile phages and theoretical and practical knowledge on pre-clinical, therapeutic evaluation of the safety and effectiveness of phage therapy for CDI

    GGE biplot based assessment of yield stability, adaptability and mega-environment characterization for hybrid pigeonpea (Cajanus cajan)

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    GGE biplot methodology is a powerful tool to study relationship among test environments (E), genotypes (G) and genotype-by-environment interaction (GE). Present study was conducted on 10 short-duration genotypes in five test environments for two years, and 16 medium-duration genotypes in six test locations for three years in randomized complete block design with two replications. In short-maturity group three mega-environments (ME) were found—ME1 comprised of Phaltan, Patancheru and Hyderabad1; ME2 and 3 constituted Jalna and Aurangabad, respectively. In scenario of limited resources, Patancheru may be a good testing location for general adaptability of short-duration hybrids, while Aurangabad and Hyderabad1 may be right environments for testing specific adaptation of short-duration cultivars in pigeonpea. ICPH 2433 was a winning genotype in ME1 in terms of high yield and stability. In medium-maturity group, two MEs were observed. Jalna, Jalna 1, Parbhani and Hyderabad grouped together as ME1, while Patancheru and Phaltan formed the second mega-environment (ME2). Parbhani was found to be most representative of all the six test locations. Jalna (ME1) and Phaltan (ME2) produced longest environment vectors, and hence may be regarded as highly discriminating. In mediummaturity group ICPH 2673 was found to be stable and high-yielding genotype for ME

    GGE biplot based assessment of yield stability, adaptability and mega-environment characterization for hybrid pigeon pea (Cajanus cajan

    Get PDF
    ABSTRACT GGE biplot methodology is a powerful tool to study relationship among test environments (E), genotypes (G) and genotype-by-environment interaction (GE). Present study was conducted on 10 short-duration genotypes in five test environments for two years, and 16 medium-duration genotypes in six test locations for three years in randomized complete block design with two replications. In short-maturity group three mega-environments (ME) were found-ME1 comprised of Phaltan, Patancheru and Hyderabad1; ME2 and 3 constituted Jalna and Aurangabad, respectively. In scenario of limited resources, Patancheru may be a good testing location for general adaptability of short-duration hybrids, while Aurangabad and Hyderabad1 may be right environments for testing specific adaptation of short-duration cultivars in pigeonpea. ICPH 2433 was a winning genotype in ME1 in terms of high yield and stability. In medium-maturity group, two MEs were observed. Jalna, Jalna 1, Parbhani and Hyderabad grouped together as ME1, while Patancheru and Phaltan formed the second mega-environment (ME2). Parbhani was found to be most representative of all the six test locations. Jalna (ME1) and Phaltan (ME2) produced longest environment vectors, and hence may be regarded as highly discriminating. In mediummaturity group ICPH 2673 was found to be stable and high-yielding genotype for ME1

    Development of ‘super-early’ pigeonpeas with good yield potential from early × early crosses

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    To enhance the adaptability of pigeonpea at higher latitude and altitude, a breeding program was initiated at ICRISAT involving different sources of early-maturity. A full diallel mating design involving 11 early-maturing lines were used as parents. In F2–F5 generations, selection was followed for early flowering and maturity, grain yield and 100-seed weight by pedigree method. Four brown seeded (ICPX 060064-4-6-10, ICPX 060077-6-5-14, ICPX 060064-4-6-2 and ICPX 060063-11-8-4) and one cream seeded (ICPX 060036-13-4-8) F4/F5 indeterminate super-early progenies that matured, respectively 25 and 23 days earlier than the control cultivar ICPL 88039 were recovered. ICPX 060036-13-4-8 recorded 107% and 34% grain yield advantage over the checks ICPL 86022 and ICPL 88039, respectively. These super-early lines were derived from crosses involving AL 1518-2 × ICPL 85010, AL 1621 × MN 5, AL 1518-2 × MN 8 and MN 8 × AL 1518-2. Other super-early progenies [ICPX 060016-10-8-1 (from MN 1 × AL 1518-2 cross) and ICPX 060017-12-12-20 (from MN 1 × AL 1621 cross)] with greater 100-seed weight were also recovered. Besides serving as excellent donors for earliness, these lines may be photo/thermo insensitive. These super-early pigeonpea lines may open new niches for this crop and help in intensification of farming system

    The spatio-relational nature of urban innovation systems: Universities, knowledge intensive business service firms, and collaborative networks

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    The need to better identify the spatio-relational nature of urban innovation systems and spaces is increasingly acknowledged. The aim of this paper, therefore, is to provide an enhanced understanding of the knowledge networks existing between urban Knowledge Intensive Business Services firms (KIBS) and universities, which are often key components of such systems and spaces. Drawing on an analysis of urban KIBS firms and universities in the UK, it is found that the nature of firms, the location in which they are based, and the research intensity of their university partners are important determinants of the spatiality and localisation of the networks they form. The results show that the smallest urban KIBS firms have the highest propensity to engage in local links with universities, suggesting that they rely most significantly on their own urban innovation system for collaborative network ties. Keywords : innovation systems; urban innovation spaces; knowledge-based development; proximity; networks; KIBS; universities

    Genre, Gender and Television Screenwriting: The Problem of Pigeonholing

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    This article draws on the 2018 Writers Guild of Great Britain report ‘Gender Inequality and Screenwriters’, and original interviews with female screenwriters, to assess how the experience of genre plays out in the UK television industry. The report focuses on the experience of women, as a single category, but we aim to reveal a more intersectional understanding of their experiences. Our aim is to better understand the ways in which women are, according to the report, consistently ‘pigeonholed by genre and are unable to move from continuing drama or children’s programming to prime-time drama, comedy or light-entertainment’. Considering the cultural value of genre in relation to screenwriting labour and career progression, we analyse how genre shapes career trajectory, arguing that social mobility for female screenwriters is inherently different and unequal to that of their male counterparts
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