25 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

    Evaluation of the Interfacial Interaction Ability between Basalt Fibers and the Asphalt Mastic

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    The interfacial properties between the asphalt mastic and fibers plays an essential role in the fiber-enhanced asphalt mixture properties. However, there is a lack of comprehensive studies on the indicators to evaluate the interfacial interaction ability of fibers with the asphalt mastic. Therefore, this paper selected three types of basalt fibers (denoted as A-BF, B-BF and C-BF) coated with different impregnating agents to prepare the fiber asphalt mastic. The Dynamic Shear Rheometer (DSR) test-based indicators, pull-out strength, and adhesion work were used to access the fiber asphalt mastic interfacial interaction ability. The differences between different indicators were compared and analyzed. The results show that all the selected indicators in this paper can effectively reflect the different fiber asphalt mastic interfacial properties. The evaluation results with different indicators are consistent. The interfacial interaction between fibers and the asphalt mastic increases with increasing temperature. The evaluation result with adhesion work is the most accurate. However, the pull-out strength test is simple, and the test result correlates well with adhesion work, which can be adopted daily to evaluate the fiber asphalt mastic interfacial properties

    Mixed Organizational Forms - A Generalization and Comparative Case Study on the ETRE Systems of China and the EU

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    There is a lack of applicable model for understanding stability affected by combination of incentive and direct control for an economic regulation within mixed-forms. The research on stability of an economic regulation has mostly been focused on incentive or direct control in a U-form or M-form dominated organization. Therefore, the purpose of this study has been to discover a universal model for explaining stability affected by combination theory, leading to high mixed-form organizations performance. This dissertation illustrates the relative theories bound to the research topic and moves one step forward into hierarchies, the U-form dominated and M-form dominated mixed forms. And this dissertation puts forward a hypothesis on how to lead an economic regulation to more stable. The suggested theory was empirically tested in a case study and received strong support. The conclusion of the conducted research is that an economic regulation governed by an M-form dominated organization with stronger incentive and less direct control is more stable than a U-form dominated organization with weaker incentive and more direct control

    Mixed Organizational Forms - A Generalization and Comparative Case Study on the ETRE Systems of China and the EU

    No full text
    There is a lack of applicable model for understanding stability affected by combination of incentive and direct control for an economic regulation within mixed-forms. The research on stability of an economic regulation has mostly been focused on incentive or direct control in a U-form or M-form dominated organization. Therefore, the purpose of this study has been to discover a universal model for explaining stability affected by combination theory, leading to high mixed-form organizations performance. This dissertation illustrates the relative theories bound to the research topic and moves one step forward into hierarchies, the U-form dominated and M-form dominated mixed forms. And this dissertation puts forward a hypothesis on how to lead an economic regulation to more stable. The suggested theory was empirically tested in a case study and received strong support. The conclusion of the conducted research is that an economic regulation governed by an M-form dominated organization with stronger incentive and less direct control is more stable than a U-form dominated organization with weaker incentive and more direct control

    Study on purification effect of infiltration materials to pavement runoff pollution

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    The concentrations of pollutants in pavement runoff are higher than those in other surface runoff normally, which causes serious problems in protecting the environment of receiving rivers and soils. According to the concept of low impact development (LID), a pavement runoff pollution control measure was developed by using infiltration structure. In order to infiltration structure play a superior role in the control of pavement runoff pollution, purification capacity of four typical infiltration materials was tested. Then, long-term purification efficiency of infiltration materials was explored to suspended solids. Besides, microscopic observation was performed on infiltration materials. Results indicated that purification effects of infiltration materials were significantly different. The purification process can be divided into three stages, which ware "rapid upgrading ", "slow upgrading " and "slow reduction ". Finally, Infiltration materials mainly have two modes to intercept runoff pollutants, which were pore adsorption and mechanical interception of the gap between materials

    Prediction of Crack Resistance of LFSMA-13 with and without Anti-Rut Agent Using Parameters of FTIR Spectrum under Different Aging Degrees

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    This paper aims to better analyze the crack resistance of lignin fiber reinforced SMA-13 (LFSMA-13) asphalt mixtures, with and without polymer anti-rut agent (ARA), under different aging degrees. IDEAL-CT test and Fourier transform infrared (FTIR) spectroscopy were utilized to analyze the relationships between the crack resistance of LFSMA-13, with and without ARA, and the parameters of the FTIR spectrum of the asphalt extracted from the test samples. A convenient testing method to predict the anti-crack ability of the mixtures in a road was also derived in this study. The test samples were prepared using the specifications listed by AASHTO. The fracture formation work (Winitial) and cracking index (CTIndex) in the IDEAL-CT test were adopted to reflect the cracking ability of the asphalt mixtures in both the crack formation stage and the crack propagation stage. The peak areas of the FTIR spectrum were utilized to reveal the chemical properties of the asphalt material inside the SMA-13 asphalt mixtures, with and without ARA under different aging degrees. Grey correlation analysis was adopted to choose the most suitable FTIR spectrum parameters to derive the prediction models of Winitial and CTIndex under different aging degrees. After conducting a series of tests, the results showed that the aging process could well affect the crack resistance of the test samples and the peak areas of the asphalt extracted from the mixtures. The FTIR parameters selected from the grey correlation analysis could be used to well predict the anti-crack ability of the asphalt mixtures

    Suitability of Fiber Lengths for Hot Mix Asphalt with Different Nominal Maximum Aggregate Size: A Pilot Experimental Investigation

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    Fiber length is a key parameter for the mixture design of basalt fiber-reinforced hot mix asphalt (HMA), which significantly affects the mix performance. To evaluate the suitability of fiber lengths for HMA with different nominal maximum aggregate size (NMAS), basalt fiber with the lengths of 3, 6, 9, 12, and 15 mm were selected for dense graded gradations with different NMASs (namely, SUP-13, SUP-20, and SUP-25), so as to prepare the fiber-reinforced HMA mixtures. Then, the mix performance was evaluated by an indirect tensile asphalt cracking test (IDEAL-CT), a four-point bending beam fatigue test, a wheel tracking test, a uniaxial penetration test, a low temperature bending beam test, and a freeze-thaw splitting test. Based on the performance results, the optimum fiber length for each mix gradation was proposed by the normalization method. The results showed that adding basalt fiber can enhance the comprehensive performance of all three types of HMA to a great extent. Furthermore, fiber length presented remarkable impact on the crack resistance, the fatigue resistance of the HMA, and the low temperature crack resistance, but it had limited influence on the high temperature deformation resistance, and water stability. The optimum fiber length for SUP-13, SUP-20, and SUP-25 was 6, 9, and 12 mm, respectively

    Study on purification effect of infiltration materials to pavement runoff pollution

    No full text
    The concentrations of pollutants in pavement runoff are higher than those in other surface runoff normally, which causes serious problems in protecting the environment of receiving rivers and soils. According to the concept of low impact development (LID), a pavement runoff pollution control measure was developed by using infiltration structure. In order to infiltration structure play a superior role in the control of pavement runoff pollution, purification capacity of four typical infiltration materials was tested. Then, long-term purification efficiency of infiltration materials was explored to suspended solids. Besides, microscopic observation was performed on infiltration materials. Results indicated that purification effects of infiltration materials were significantly different. The purification process can be divided into three stages, which ware "rapid upgrading ", "slow upgrading " and "slow reduction ". Finally, Infiltration materials mainly have two modes to intercept runoff pollutants, which were pore adsorption and mechanical interception of the gap between materials

    Evaluation of the Long-Term Performances of SMA-13 Containing Different Fibers

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    To clarify the influence of fiber type on the long-term performance of stone mastic asphalt (SMA), this paper used basalt fiber (BF) and lignin fiber (LF) to modify SMA-13 (SMA with aggregate nominal maximum particle size of 13.2 mm) asphalt mixture. The pavement performances (high-temperature performance, cracking resistance at low and medium temperature, and water stability) of the two kinds of fiber-reinforced SMA-13 were checked under different aging degrees (unaged, short-term aged and long-term aged), scanning electron microscope (SEM) test was conducted to explain the strengthening mechanism of the fibers. Fourier transform infrared spectrometry (FTIR) was used to analyze the changes in the chemical composition of asphalt after aging. The results of the wheel tracking test and uniaxial penetration test showed that the high-temperature performance of the BFSMA-13 (defined as the SMA-13 containing BF) is better than that of the LFSMA-13 (defined as the SMA-13 containing LF) at different aging degrees. The high-temperature performance of BFSMA-13 increases with the increase of the aging degree, while the aging process decreases the high-temperature property of LFSMA-13. The results of the three-point bending test and semi-circular bending (SCB) proved that BFSMA-13 is more capable of deformation and less prone to cracking at low and medium temperatures. The results of the immersion Marshal test indicated that BF can better improve the strength and the water stability of the SMA-13 mixture than LF. The SEM images showed that basalt fibers form a solid three-dimensional network structure in the mixture which could contribute to the strengthening of the mixture. The results of infrared spectroscopy analysis showed that styrene–butadiene–styrene (SBS) degrades during asphalt mixture aging, and that the chemical composition of asphalt changes more after aging in LFSMA-13 than in BFSMA-13. The conclusions of this study help toward further understanding of the performance changes of the SMA-13 mixture during its service life and to guide the selection of fiber additives for SMA-13 mixtures
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