332 research outputs found

    Multiple-target CW FM radar

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    Development of a multiple-target CW FM radar is described. This type of radar has advantages over pulse radars particularly in portable, battery operated applications.http://archive.org/details/multipletargetcw00hoisN

    Propane Dehydrogenation Using Transition Metal Cluster Catalysts

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    Our research seeks to determine the propane dehydrogenation (PDH) reaction pathways using various transition-metal cluster catalysts. We are studying the first step of the reaction, in which a C-H bond is broken. This has been previously shown to be the rate-limiting step of the PDH reaction. We are calculating the PDH activation energy (Ea) using the Vienna Ab-Initio Simulation Package (VASP) in conjunction with the nudged elastic band algorithm. Thus far, we have studied Pt, Ta, and Ni clusters ranging in size from 2-10 atoms. Our goal is to better understand the dependence of Ea on metal type and cluster size

    The Center of Excellence in Genomics (CEG) for enhancing the utilization of molecular tools in breeding and research

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    ICRISAT has partnered with the Department of Biotechnology (DBT), Government of India, to establish the Center of Excellence in Genomics (CEG) at ICRISAT with financial support from the DBT. The CEG was launched through an exchange of a Memorandum of Agreement (MoA) signed by Dr William Dar, Director General of ICRISAT and Dr MK Bhan, Secretary of DBT on 13 December 2006 at a function organized at ICRISAT headquarters at Patancheru, India (see photo)

    Research and field monitoring on transgenic crops by the Centro Internacional de Mejoramiento de Maíz y Trigo (CIMMYT)

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    The International Maize and Wheat Improvement centre (CIMMYT) aims to genetically enhance both crops and generate public sector-provided products for the resource poor, e.g., drought tolerant wheat and insect resistant maize, and through international-national partnerships facilitate the acquisition of improved germplasm for non-mandate crops in the cropping systems where maize and wheat thrives; e.g., GM-papaya through a national food security undertaking in Bangladesh. The centre also engages in public awareness campaigns in projects such as Insect Resistance Maize for Africa (IRMA), which includes food, feed and environmental safety, monitoring of resistance and establishment of refugia, non-target effects and gene flow. Monitoring of genetic resources is a wide concern among the centres of the Consultative Group on International Agricultural Research (CGIAR), with an emphasis on the quality of gene banks. Decisions, policies and procedures about monitoring should be science-based, and this requires education, an area where CIMMYT and other CGIAR centres can play an important role. There will be a need to continue to evaluate the need for, and type of monitoring, as new (and unique) products are developed and released in the emergent economies of the world

    Bioinformatics tools for crop research and breeding

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    Crop improvement has always been, but will be even more so in the twenty-first century, an information intensive process. For effective and efficient improvement, a range of activities from molecular biology to genetics to indirect selection must now be involved. The rate of progress made by any breeding programme depends as much on the efficient integration of information from these activities as it does on the activities themselves. Plant breeders are now realizing the importance of innovative approaches that include the use of a range of molecular methods and their outputs, and the possibilities of transferring this information from model species to cultivated crops. The use of these high throughput methods in model crops has already generated a large amount of public resources such as databases containing genetic resource, genomic and genetic information; tools for the effective analysis, data mining and visualization of such information; and semantic web resources for data integration. In this chapter, we highlight the role and contributions of bioinformatics to crop research and breeding by focusing on the bioinformatics resources that are available for crop science research and breeding, and indicating gaps that need to be bridged that will allow scientists to access, transfer and integrate data with eas

    Peanut improvement: production of fertile hybrids and backcross progeny between Arachis hypogaea and A. kretschmeri

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    There are only a few reports of successful crosses between cultivated peanut (Arachis hypogaea L., section Arachis) and wild species from sections other than section Arachis. Many of the wild Arachis species harbor important traits necessary for the improvement of peanut. For example, Arachis kretschmeri Krapov., W.C. Gregory & C.E. Simpson (section Procumbentes) can grow under water-logged conditions and has been identified as one of the few wild species of Arachis with resistance to late leaf spot (LLS) and peanut rosette disease. Peanut rosette, caused by a combination of viruses, is an economically important disease only in Africa, while LLS, caused by Cercosporidium personatum, is an important fungal disease in Asia and the Americas as well as Africa. Interspecific hybrids between A. hypogaea and A. kretschmeri were produced by applying growth regulators to pollinated pistils and hybrid plants were obtained by germinating embryos in vitro. A total of seven hybrids were produced and confirmed by Simple Sequence Repeat (SSR) analysis. All hybrids were fertile, although initially slow growing. F1 hybrids were backcrossed to A. hypogaea and all plants in the F1BC1 generation were single-seeded with a prominent beak, characteristic of A. kretschmeri, but many of the F1BC2 pods were double-seeded resembling A. hypogaea. F1BC2 plants were moderately resistant to LLS. When a large number of seeds are obtained, the progeny will be screened for resistance to both LLS and rosette disease. Thus crosses with species outside the section Arachis may not only confer disease resistance but will also broaden the genetic base of cultivated peanut

    Genetic diversity in Indian isolates of Fusarium oxysporum f. sp. ciceris, chickpea wilt pathogen

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    Forty-eight isolates of FOC collected from different chickpea growing regions in India were evaluated for genetic variations using amplified fragment length polymorphism (AFLP). Out of 48 isolates, 41 werefound pathogenic and seven non-pathogenic. Pathogenic isolates differ in their virulence however; there was no apparent correlation between geographical origin and virulence of the isolates. The genetic variation was evaluated by the AFLP analysis. A total 339 fragments were scored following selective amplification with five EcoR1 and Mse1 primer combinations E-TC/M-CAT, E-TC/M-CAC, EAC/ M-CAG, E-TA/MCAG, E-TA/M-CAG, out of which 331 fragments were polymorphic. UPGMA cluster analysis and principle coordinate analysis distinctly classified 48 isolates into two major groups; pathogenic and non-pathogenic. The pathogenic isolates could be further clustered into six majorgroups at 0.77 genetic similarities. Region specific grouping was observed with in few isolates. The results of the present study provide evidence of the high discriminatory power of AFLP analysis,suggesting the applicability of this method to the molecular characterization of Fusarium oxysporum f.sp. ciceris

    Molecular markers for plant breeding: comparisons of RFLP and RAPD genotyping costs

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    Three molecular marker protocols, chemiluminescent restriction fragment length polymorphisms (c-RFLPs), radioactivity-based restriction fragment length polymorphisms (r-RFLPs), and randomly amplified DNA polymorphisms (RAPDs) were compared in terms of cost and time efficiency. Estimates of cost of supplies and time requirements were obtained from simulations of maize (Zea mays L.) genotyping experiments utilizing protocols currently in use. The increase in total cost with increasing numbers of individuals genotyped and markers analyzed is higher for RAPDs than for RFLPs. RAPDs were generally found to be more cost and time efficient for studies involving small sample sizes, while RFLPs have the advantage for larger sample sizes. Because of the shorter exposure times involved, c-RFLPs require less time than r-RFLPs to obtain a given amount of information. Variations in the protocols, such as number of re-uses of Southern blots or cost of Taq DNA polymerase per reaction of amplification, also affect the relative merits of RAPDs and RFLPs. Two examples were analyzed where molecular markers are used: a germ plasm survey and quantitative trait loci (QTL) mapping in a segregating population. No protocol was found to be the most cost and time efficient over the entire range of sample sizes and number of marker loci studied

    Optimizing the Environmental and Economic Sustainability of Remote Community Infrastructure

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    Remote communities such as rural villages, post-disaster housing camps, and military forward operating bases are often located in remote and hostile areas with limited or no access to established infrastructure grids. Operating these communities with conventional assets requires constant resupply, which yields a significant logistical burden, creates negative environmental impacts, and increases costs. For example, a 2000-member isolated village in northern Canada relying on diesel generators required 8.6 million USD of fuel per year and emitted 8500 tons of carbon dioxide. Remote community planners can mitigate these negative impacts by selecting sustainable technologies that minimize resource consumption and emissions. However, the alternatives often come at a higher procurement cost and mobilization requirement. To assist planners with this challenging task, this paper presents the development of a novel infrastructure sustainability assessment model capable of generating optimal tradeoffs between minimizing environmental impacts and minimizing life-cycle costs over the community’s anticipated lifespan. Model performance was evaluated using a case study of a hypothetical 500-person remote military base with 864 feasible infrastructure portfolios and 48 procedural portfolios. The case study results demonstrated the model’s novel capability to assist planners in identifying optimal combinations of infrastructure alternatives that minimize negative sustainability impacts, leading to remote communities that are more self-sufficient with reduced emissions and costs

    Propane Dehydrogenation Using Transition Metal Cluster Catalysts

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    Our research seeks to determine the propane dehydrogenation (PDH) reaction pathways using various transition-metal cluster catalysts. We are studying the first step of the reaction, in which a C-H bond is broken. This has been previously shown to be the rate-limiting step of the PDH reaction. We are calculating the PDH activation energy (Ea) using the Vienna Ab-Initio Simulation Package (VASP) in conjunction with the nudged elastic band algorithm. Thus far, we have studied Pt, Ta, and Ni clusters ranging in size from 2-10 atoms. Our goal is to better understand the dependence of Ea on metal type and cluster size
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