6 research outputs found

    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

    Refractory petrochemical wastewater treatment by K2S2O8 assisted photocatalysis

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    The K2S2O8 assisted photocatalytic system was applied for treating refractory petrochemical wastewater. Co-TiO2/zeolite catalyst synthesized by sol-gel method was demonstrated to possess a good activity towards mineralization of the refractory petrochemical wastewater in the K2S2O8 assisted photocatalytic system. Orthogonal design was employed to optimize the reaction parameters, according to the results, K2S2O8 dosage was the most prominent impact factor. More experiments were conducted to further enhance the COD removal efficiency. In consideration of both efficiency and costs, the petrochemical wastewater was treated in the K2S2O8 assisted photocatalytic system at pH 4, K2S2O8 dosage 2.03 g/L, catalyst amount 250 g/L with irradiation by 1 lamp and aeration. The COD removal efficiency reached up to 93.4% with a rate constant of 1.14 × 10−2 per min, and Co-TiO2/zeolite showed a good stability towards the K2S2O8 assisted photocatalytic degradation of petrochemical wastewater. Keywords: Refractory petrochemical wastewater, K2S2O8 assisted photocatalysis, Co-TiO2/zeolite, Sulfate radica

    Variability of Sedimentary Phosphorus Fractions in the Western and Sandusky Basins of Lake Erie

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    Surface sediments and three sediment cores from the western basin and one sediment core from the Sandusky basin were analyzed to document spatial and temporal changes in five phosphorus fractions and total phosphorus (TP). The areal distributions of the bioavailable fractions NaCl-Pi, NaBD-Pi, and NaOH-Pi and the refractory organic fraction Res-P were broadly consistent and contrasted with those of the detrital fraction HCl-Pi which showed that high concentrations occurred mostly in high-energy littoral zones and low concentrations largely in profundal depositional areas. The contrasting distributions were induced by interactions among tributary inputs, wave action, circulation, and biogeochemical cycling and transfer in the basin. As revealed by the Sandusky basin sediment record, the detrital fraction HCl-Pi was dominant (70% of TP) during European settlement and decreased rapidly by 28.0% in the early 1910s due largely to impoundments of the Maumee and Sandusky Rivers. While HCl-Pi has ever since remained relatively constant, NaCl-Pi, NaBD-Pi, and NaOH-Pi increased significantly between 1950 and 1970 in the two basins. However, the post-regulation sediment records differed considerably among these coring sites. There was a marked increase of TP in two cores, corresponding to recent return of eutrophication and massive harmful algal blooms but contrasting with a relatively constant, low loading into the lake. This signified the role of internal loading as derived partialy from legacy pollution. Furthermore, NaCl-Pi has increased progressively throughout all the records. We conclude that the increased levels of NaCl-Pi in surface sediments may have altered the internal loading and contributed to the resurgences of harmful algal blooms in Lake Erie
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