15 research outputs found

    Detailed Analysis of a Contiguous 22-Mb Region of the Maize Genome

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    Most of our understanding of plant genome structure and evolution has come from the careful annotation of small (e.g., 100 kb) sequenced genomic regions or from automated annotation of complete genome sequences. Here, we sequenced and carefully annotated a contiguous 22 Mb region of maize chromosome 4 using an improved pseudomolecule for annotation. The sequence segment was comprehensively ordered, oriented, and confirmed using the maize optical map. Nearly 84% of the sequence is composed of transposable elements (TEs) that are mostly nested within each other, of which most families are low-copy. We identified 544 gene models using multiple levels of evidence, as well as five miRNA genes. Gene fragments, many captured by TEs, are prevalent within this region. Elimination of gene redundancy from a tetraploid maize ancestor that originated a few million years ago is responsible in this region for most disruptions of synteny with sorghum and rice. Consistent with other sub-genomic analyses in maize, small RNA mapping showed that many small RNAs match TEs and that most TEs match small RNAs. These results, performed on ∼1% of the maize genome, demonstrate the feasibility of refining the B73 RefGen_v1 genome assembly by incorporating optical map, high-resolution genetic map, and comparative genomic data sets. Such improvements, along with those of gene and repeat annotation, will serve to promote future functional genomic and phylogenomic research in maize and other grasses

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Paramter Form for Subsystem: Liquid Freeze-Thaw (Liquid Freeze Thaw)

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    5 pages Provider Notes:Subsystem parameters and graphs gathered from meeting with Jeff Schmid

    Urine Processing for Water Recovery via Freeze Concentration

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    Resource recovery, including that of urine water extraction, is one of the most crucial aspects of long-term life support in interplanetary space travel. This paper will consequently examine an innovative approach to processing raw, undiluted urine based on low-temperature freezing. This strategy is uniquely different from NASA\u27s current emphasis on either \u27integrated\u27 (co-treatment of mixed urine, grey, and condensate waters) or \u27high temperature\u27 (i.e., VCD [vapor compression distillation] or VPCAR [vapor phase catalytic ammonia removal]) processing strategies, whereby this liquid freeze-thaw (LiFT) procedure would avoid both chemical and microbial cross-contamination concerns while at the same time securing highly desirable reductions in likely ESM levels. The involved freeze concentration methodology is a low energy process that focuses on the nucleation of pure ice crystals followed by a ripening effect of those crystals and subsequent washing to achieve high extraction efficiencies. A theoretical water recovery value of approximately 88% has been determined based on the eutectic points of the expected urine constituents. Overall, this research paper will focus on several aspects of freeze concentration, including an overview of the basic technology and its various pragmatic applications, as well as a theoretical comparison of model percent recovery rates relative to observed experimental operational values. Detailed testing results will also be presented to confirm the observed low-level migration of inorganic, organic, and biological contaminants into the product water

    ALS-NSCORT Solid Waste Team: NSCORT Kick off Meeting, 5-8-03

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    16 slides Provider Notes:A variety of files used in the presentations for the kick off meeting. Also, Dr. Alleman\u27s notes on the review panel\u27s comments, and response to questions sent to Jitendra Joshi. Related Documents:WWAS7a, WWAS7b, WWAS7d, WWAS7

    Suppression of the Cu2−xS{\hbox{Cu}}_{2-x}{\hbox{S}} Secondary Phases in CZTS Films Through Controlling the Film Elemental Composition

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    Kesterite Cu2 ZnSnS4 (CZTS) thin films were grown by the sulfurization of stacked metal precursors deposited using radio-frequency magnetron sputtering on Mo-coated soda-lime glass substrates. In this paper, we report the role of the film chemical composition in the evolution of Cu 2-x S phases and how to avoid their development through controlling the film composition. Furthermore, the effect of the elemental concentration on the structural and morphological properties of the final CZTS films has been investigated. The prepared CZTS films have a composition ratio M = Cu/(Zn + Sn) varying from 0.81 (Cu-poor) to 1.05 (Cu-rich). X-ray diffraction and Raman scattering studies revealed the presence of Cu 2-x S phases in films with a Cu/(Zn + Sn) ratio higher than 1.00 and/or in films with a Sn/Cu ratio close to or less than the stoichiometric value of 0.50. However, Cu 2-x S-phases-free CZTS films were achieved with Sn/Cu ratios sufficiently above 50% without regard to the Cu/(Zn + Sn) ratio. Plan and cross-sectional scanning electron microscopy showed compact films, in general. Electron back-scattered diffraction revealed randomly oriented CZTS films

    No observed association for mitochondrial SNPs with preterm delivery and related outcomes

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    BACKGROUND: Preterm delivery (PTD) is the leading cause of neonatal morbidity and mortality. Epidemiologic studies indicate recurrence of PTD is maternally inherited creating a strong possibility that mitochondrial variants contribute to its etiology. This study examines the association between mitochondrial genotypes with PTD and related outcomes. METHODS: This study combined, through meta-analysis, two case-control, genome-wide association studies (GWAS); one from the Danish National Birth Cohort (DNBC) Study and one from the Norwegian Mother and Child Cohort Study (MoBa) conducted by the Norwegian Institute of Public Health. The outcomes of PTD (≤36 weeks), very PTD (≤32 weeks) and preterm prelabor rupture of membranes (PPROM) were examined. 135 individual SNP associations were tested using the combined genome from mothers and neonates (case vs. control) in each population and then pooled via meta-analysis. RESULTS: After meta-analysis there were four SNPs for the outcome of PTD below p≤0.10, and two below p≤0.05. For the additional outcomes of very PTD and PPROM there were three and four SNPs respectively below p≤0.10. CONCLUSION: Given the number of tests no single SNP reached study wide significance (p=0.0006). Our study does not support the hypothesis that mitochondrial genetics contributes to the maternal transmission of PTD and related outcomes
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