100 research outputs found

    イソニトリルの重合と金属錯体との反応に関する研究

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    Trace amounts of Pt- and Ru-doped Ni/Mg(Al)O catalysts were prepared by a citrate method and tested in the oxidative reforming of C3H8 under daily start-up and shut-down (DSS) operation. The activity and the sustainability of the catalysts were compared with those of the Pt- and Ru-doped Ni/Mg(Al)O catalysts derived from hydrotalcite (HT) precursor. The DSS operation of C3H8 reforming was carried Out with O-2 gas or O-2/H2O mixed gas between 200 degrees C and 600 degrees C or 700 degrees C under air purging conditions. The catalysts underwent steaming treatment with H-2/H2O mixed gas at 900 degrees C for 10 h. This allowed us to test the effect of Ni sintering on the catalyst deactivation. Coking was significantly suppressed on both HT- and citrate-derived Ni catalysts. Although both preparations produced highly dispersed Ni particles on the catalysts, the HT-derived catalysts exhibited more finely dispersed Ni particles, resulting in higher activity values than those of the citrate-derived catalysts, The regenerative activity due to redispersion of sintered Ni particles was enhanced over the HT-derived catalysts compared with the activity over citrate-derived catalysts. Although a clear redispersion of Ni particles was not observed in the oxidative reforming, i.e., in the absence of steam, the size decrease in Ni particles was more significant over the HT-derived catalysts than over the citrate-derived catalysts. The Mg(Al)O periclase structure derived from Mg-Al HT likely plays an important role in the regenerative activity of Pt- and Ru-Ni/Mg(Al)O catalysts. Pt-doping was more effective than Ru for the catalyst sustainability in the oxidative reforming of C3H8

    Perbandingan Harga Energi dari Sumber Energi Baru Terbarukan dan Fosil

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    PERBANDINGAN HARGA ENERGI DARI SUMBER ENERGI BARU TERBARUKAN DAN FOSIL. Transportasi biaya rendah untuk orang dan barang sangat penting untuk kesejahteraan ekonomi bangsa. Hingga kini jika harga minyak naik, biaya transportasi otomatis akan mengikuti dan sebagian rakyat menderita akibat melambungnya harga makanan dan barang-barang lainnya. Hampir 100 persen kebutuhan energi transportasi negara Indonesia didukung oleh minyak. Sementara biaya di sektor energi terutama listrik, di negara maju yang juga berperan signifikan untuk mendukung transportasi, jauh lebih stabil dan dapat diprediksi. Kebutuhan energi yang begitu tinggi di sektor transportasi cenderung memaksa manusia untuk mengupayakan sumber dan sarana energi dalam bentuk lain seperti listrik atau hydrogen yang dapat menyamai atau melebihi kinerja bahan bakar minyak. Makalah ini bertujuan untuk menganalisis perbandingan keekonomian harga energi dari sumber EBT dan fosil untuk melihat sejauh mana peluang keekonomian beberapa jenis energi dapat memainkan peran signifikan di sektor transportasi dan dampak selanjutnya di dalam sistem energi. Metodologi yang digunakan adalah penelusuran pustaka dan perhitungan langsung pada bahan atau sumber energi terkait. Dari hasil analisis diperoleh bahwa akan semakin dibutuhkan peran energi nuklir dan energi tertentu lainnya sebagai sumber energi listrik menimbang aspek keekonomiannya yang relatif lebih baik

    The Impact of Chronic Heat Stress on the Growth, Survival, Feeding, and Differential Gene Expression in the Sea Urchin Strongylocentrotus intermedius

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    To explore the impact of chronic heat stress on commercial echinoderms, the present study assessed the effects of chronic high temperature on the growth, survival, feeding, and differential gene expression in the sea urchin Strongylocentrotus intermedius cultured in northern Yellow Sea in China. One suitable seawater condition (20°C) and one laboratory-controlled high temperature condition (25°C) were set up. After 28 days incubation, our results showed that: (1) The specific growth, survival, and ingestion rates of S. intermedius reared under high temperature (25°C) decreased compared to those reared under optimal temperature (20°C) conditions; (2) comparative transcriptome analysis identified 2,125 differentially expressed genes (DEGs) in S. intermedius reared under high temperature (25°C) compared to those subjected to optimal temperature condition (20°C), which included 1,015 upregulated and 1,100 downregulated genes. The accuracy of the transcriptome profiles was verified by quantitative real-time PCR (qRT-PCR). Further Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analyses revealed that these DEGs mainly enriched the functional categories of ribosome, protein processing in endoplasmic reticulum, and prion diseases. A total of 732 temperature-induced expressed genes, such as ATP5, heat shock protein 70, and heat shock protein 90, were identified as candidates that were closely correlated with heat resistance in S. intermedius. Differentially expressed transcription factors (TFs), such as AP-1, Fos, CREB, and ZNF, were also identified as potential regulators that regulate the molecular network that was associated with responses to heat stress in sea urchins. Observations in the present study provide additional information that improves our understanding of the molecular mechanism of temperate echinoid species in response to heat stress, as well as theoretical basis for the molecular-assisted breeding of heat-resistant sea urchins

    Genomic analysis of oesophageal squamous-cell carcinoma identifies alcohol drinking-related mutation signature and genomic alterations

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    Approximately half of the world's 500,000 new oesophageal squamous-cell carcinoma (ESCC) cases each year occur in China. Here, we show whole-genome sequencing of DNA and RNA in 94 Chinese individuals with ESCC. We identify six mutational signatures (E1–E6), and Signature E4 is unique in ESCC linked to alcohol intake and genetic variants in alcohol-metabolizing enzymes. We discover significantly recurrent mutations in 20 protein-coding genes, 4 long non-coding RNAs and 10 untranslational regions. Functional analyses show six genes that have recurrent copy-number variants in three squamous-cell carcinomas (oesophageal, head and neck and lung) significantly promote cancer cell proliferation, migration and invasion. The most frequently affected genes by structural variation are LRP1B and TTC28. The aberrant cell cycle and PI3K-AKT pathways seem critical in ESCC. These results establish a comprehensive genomic landscape of ESCC and provide potential targets for precision treatment and prevention of the cancer

    Robust estimation of bacterial cell count from optical density

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    Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

    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

    Effect of lobaplatin on proliferation and apoptosis of hepatocellular carcinoma HepG2 cells and related mechanism of action

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    ObjectiveTo investigate the effect of lobaplatin on the proliferation and apoptosis of hepatocellular carcinoma (HCC) HepG2 cells in vitro and related mechanism of action. MethodsHepG2 cells were divided into lobaplatin group (proliferation assay: 5 μmol/L, 10 μmol/L, and 15 μmol/L; apoptosis assay: 10 μmol/L; invasion assay: 4 μg/ml) and control group (no drug was added). CCK-8 assay and flow cytometry were used to measure the proliferation and apoptosis of HepG2 cells. Western Blot was used to measure the change in the expression of NF-κB, Bcl-2, Bax, Bid, Puma, and caspase-3 proteins involved in proliferation and apoptosis. A two-way analysis of variance was used for proliferation assay, the chi-square test was used for apoptosis assay, and the t-test was used for invasion assay. ResultsAfter intervention for 24, 48, and 72 hours, there was a significant difference in proliferation inhibition rate between the two groups (F=273.5, P<0.01); there was also a significant difference between different concentration groups at the same time point (F=1857, P<0.01), and all the concentration groups showed a significant change over time (F=1365, P<0.01). As for apoptosis, there was a significant difference in apoptosis rate between the two groups (χ2=1821, P<0.001). As for invasion ability, compared with the control group, the lobaplatin group had a significantly lower number of cells passing through the Transwell chamber (2130±2.74 vs 45.00±4.26, t=11.89, P<0.001). As for proteins, the lobaplatin group had a significant reduction in the expression of Bcl-2 and significant increases in the expression of NF-κB, Bax, Puma, and caspase-3. ConclusionLobaplatin exerts a certain effect on the proliferation and apoptosis of HCC HepG2 cells by affecting the proteins involved in proliferation and apoptosis, but further studies are needed due to complex signaling pathways in cells
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