To predict the structures, properties, and chemistry of materials involving silicon and silicon oxides; interfaces between these materials; and hydrolysis of such systems, we have developed the ReaxFF SiO , reactive force field. The parameters for this force field were obtained from fitting to the results of quantum chemical (QC) calculations on the structures and energy barriers for a number of silicon oxide clusters and on the equations of state for condensed phases of Si and SiO 2 from QC. We expect that ReaxFF SiO will allow accurate dynamical simulations of bond breaking processes in large silicon and silicon oxide systems. ReaxFF SiO is based closely on the potential functions of the ReaxFF CH reactive force field for hydrocarbons, so that it should also be useful for describing reactions of organics with Si and SiO 2 systems.
Sustainably feeding a growing population is a grand challenge, and one that is particularly difficult in regions that are dominated by smallholder farming. Despite local successes, mobilizing vast smallholder communities with science- and evidence-based management practices to simultaneously address production and pollution problems has been infeasible. Here we report the outcome of concerted efforts in engaging millions of Chinese smallholder farmers to adopt enhanced management practices for greater yield and environmental performance. First, we conducted field trials across China's major agroecological zones to develop locally applicable recommendations using a comprehensive decision-support program. Engaging farmers to adopt those recommendations involved the collaboration of a core network of 1,152 researchers with numerous extension agents and agribusiness personnel. From 2005 to 2015, about 20.9 million farmers in 452 counties adopted enhanced management practices in fields with a total of 37.7 million cumulative hectares over the years. Average yields (maize, rice and wheat) increased by 10.8-11.5%, generating a net grain output of 33 million tonnes (Mt). At the same time, application of nitrogen decreased by 14.7-18.1%, saving 1.2 Mt of nitrogen fertilizers. The increased grain output and decreased nitrogen fertilizer use were equivalent to US$12.2 billion. Estimated reactive nitrogen losses averaged 4.5-4.7 kg nitrogen per Megagram (Mg) with the intervention compared to 6.0-6.4 kg nitrogen per Mg without. Greenhouse gas emissions were 328 kg, 812 kg and 434 kg CO equivalent per Mg of maize, rice and wheat produced, respectively, compared to 422 kg, 941 kg and 549 kg CO equivalent per Mg without the intervention. On the basis of a large-scale survey (8.6 million farmer participants) and scenario analyses, we further demonstrate the potential impacts of implementing the enhanced management practices on China's food security and sustainability outlook.
The association of alcohol consumption and breast cancer is more pronounced in cases that are positive for estrogen receptor (ER+) than in cases that are negative (ER-). Its mechanism remains to be determined. Deregulation of RNA polymerase III (Pol III) transcription enhances cellular tRNAs and 5S rRNA production, increasing translational capacity to promote cell transformation and tumor formation. Here, we report that alcohol increases Pol III gene transcription in both normal and cancer breast cell lines. The induction in ER+ breast cancer cells (MCF-7) is significantly higher than in ER- normal breast cells (MCF-10A, MCF-10F and MCF-12A) and is correlated with ER expression. E2 causes <2-fold increase in Pol III gene transcription. The addition of ethanol to this system now produces a 10-15-fold increase. Ethanol increases ERα expression, resulting in an increase in Brf1 protein and mRNA levels. In addition, ethanol markedly stimulates phosphorylation of JNK1, but not JNK2. Inhibition of JNK1 decreases ERE-Luc reporter activity and represses expression of ERα, Brf1 and Pol III genes. Reduction of ERα by its small interfering RNA represses Brf1 and Pol III gene transcription. Ethanol with E2 produces larger and more numerous colonies. Repression of ERα or Brf1 inhibits alcohol-induced cell transformation. Together, these results support the idea that alcohol increases ERα expression through JNK1 to elevate Brf1 expression and Pol III gene transcription to bring about greater phenotypic changes. These studies demonstrate that ERα mediates Pol III gene transcription through Brf1, suggesting that ERα may play a critical role in alcohol-induced deregulation of Pol III genes in ER+ breast cancer development.
We derive here the form for the exact exchange energy density for a density that decays with Gaussian-type behavior at long range. This functional is intermediate between the B88 and the PW91 exchange functionals. Using this modified functional to match the form expected for Gaussian densities, we propose the X3LYP extended functional. We find that X3LYP significantly outperforms Becke three parameter Lee-Yang-Parr ͑B3LYP͒ for describing van der Waals and hydrogen bond interactions, while performing slightly better than B3LYP for predicting heats of formation, ionization potentials, electron affinities, proton affinities, and total atomic energies as validated with the extended G2 set of atoms and molecules. Thus X3LYP greatly enlarges the field of applications for density functional theory. In particular the success of X3LYP in describing the water dimer ͑with R e and D e within the error bars of the most accurate determinations͒ makes it an excellent candidate for predicting accurate ligand-protein and ligand-DNA interactions.
The contributions of interleukin (IL)-17 to cancer remain unclear and somewhat controversial. We took a genetic approach to explore its role in prostate cancers by interbreeding IL-17 receptor C (IL-17RC)-deficient mice with mice that are conditionally mutant for PTEN, one established preclinical model for prostate cancer. Mice that were IL-17RC-deficient (IL-17RC À ) displayed prostates that were smaller than mice that. In addition, IL-17RC À mice developed a reduced number of invasive prostate adenocarcinomas with lower rates of cellular proliferation and higher apoptosis than IL-17RC þ mice. Moreover, the fibromuscular stroma surrounding prostatic glands was relatively thicker in IL-17RC À mice and was associated with decreased matrix metalloproteinase (Mmp)7 expression and increased Timp1, 2, and 4 expression, whereas administration of recombinant mouse IL-17 induced prostatic expression of Mmp7. Taken together, our results suggested that IL-17 promotes the formation and growth of prostate adenocarcinoma, and that an IL-17-MMP7 signaling axis is required for the transition of prostatic intraepithelial neoplasia to frank adenocarcinoma. Cancer Res; 72(10); 2589-99. Ó2012 AACR.
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