On-Step Synthesis of a Bifunctional BINOL Ligand for the Highly Enantioselective Cyanation of Aliphatic Aldehydes

An efficient one-step synthesis of the optically active bifunctional BINOL ligand (S)-3 has been developed. It was found that (S)-3 in combination with Me2AlCl is a highly enantioselective catalyst for the addition of TMSCN to aliphatic aldehydes of diverse structures and is also among the most practical ones. A remarkable positive nonlinear effect was found for this chiral ligand

Congestion Pricing for Aircraft Pushback Slot Allocation

<div><p>In order to optimize aircraft pushback management during rush hour, aircraft pushback slot allocation based on congestion pricing is explored while considering monetary compensation based on the quality of the surface operations. First, the concept of the “external cost of surface congestion” is proposed, and a quantitative study on the external cost is performed. Then, an aircraft pushback slot allocation model for minimizing the total surface cost is established. An improved discrete differential evolution algorithm is also designed. Finally, a simulation is performed on Xinzheng International Airport using the proposed model. By comparing the pushback slot control strategy based on congestion pricing with other strategies, the advantages of the proposed model and algorithm are highlighted. In addition to reducing delays and optimizing the delay distribution, the model and algorithm are better suited for use for actual aircraft pushback management during rush hour. Further, it is also observed they do not result in significant increases in the surface cost. These results confirm the effectiveness and suitability of the proposed model and algorithm.</p></div

The survival cost <i>m</i>_<i>c</i> as a function of <i>r</i> on network of different average degree <i>k</i>.

Solid lines are line fitting curves.</p

Optimization process of IDDE algorithm as implemented in MATLAB.

Optimization process of IDDE algorithm as implemented in MATLAB.</p

Delay time for each aircraft.

<p>Delay time for each aircraft.</p

Nanoaggregation of Polyaromatic Compounds Probed by Electrospray Ionization Mass Spectrometry

This paper reports the results of the first detailed experimental study on probing nanoaggregation of a polyaromatic compound. Electrospray ionization mass spectrometry (ESI–MS) was used to monitor the self-association of a well-defined polyaromatic compound, <i>N</i>-(1-hexylhepyl)-<i>N</i>′-(5-carboxylicpentyl)-perylene-3,4,9,10-tetracarboxylicbisimide (C5Pe), under various solution conditions. Gaseous ions corresponding to nanoaggregates of C5Pe molecules were directly observed on ESI mass spectra. The dominant aggregation number (<i>n</i>) was found to be less than 10, although larger nanoaggregates with an aggregation number larger than 10 were also observed. The aggregation number of C5Pe decreased by replacing toluene with xylene, while it increased with the C5Pe concentration or upon the addition of heptane to toluene as the solvent. The consecutive aggregation number was found only for small C5Pe nanoaggregates (2 ≤ <i>n</i> ≤ 11), which suggests a stepwise self-association at <i>n</i> ≤ 11. The larger nanoaggregates (<i>n</i> > 11) were formed by interactions between small nanoaggregates. The presence of naphthenic acids (NAs) was observed to hinder C5Pe self-association. The dispersive effect of NAs was found to be in the order of 1-methyl-1-cyclohexanecarboxylic acid ∼ cyclohexanebutyric acid < stearic acid < 5β-cholanic acid < 1-naphthalene pentanoic acid. The nanoaggregation behavior of C5Pe was compared to that of two other polyaromatic compounds

An isogenic experimental model identifies b-catenin as a molecular target in ovarian cancer metastasis

Session - Tumor Biology: no. 650This journal suppl. entitled: Proceedings: AACR 107th Annual Meeting 2016; April 16-20, 2016; New Orleans, LAOvarian cancer metastasis is closely associated with unfavorable outcomes, yet the underlying mechanisms remain obscure. Here we establish an isogenic model that could mimic the spontaneous metastasis of human ovarian cancer. Given that tumor cells are heterogeneous in nature, an isogenic pair of highly metastatic (HM) and non-metastatic (NM) cell lines with opposite metastatic capabilities was derived using in vitro and in vivo selection. Incorporation of the luciferase gene into the cell pair allowed non-invasive monitoring of the metastatic events by bioluminescent imaging in vivo. Orthotopic implantation of HM into the ovarian bursa of NOD/SCID mice resulted in metastases within the peritoneum with ascites formation, thus representing the major dissemination pattern of human ovarian cancer cells. However, NM failed to form detectable metastases, although it was tumorigenic at the ovarian bursa. In comparison with NM, HM displayed higher spheroid-forming ability and had higher expression of stemness marker genes, which are characteristics of cancer stem-like population. By proteomic profiling and pathway analysis, HM is found to be enriched in the oncogenic β-catenin signaling, a pathway elevated in ovarian cancer metastases. Tumor initiation and metastasis of HM was dramatically impaired when β-catenin was specifically knocked down. We further demonstrated that β-catenin could down-regulate the expression of Dicer, a major component of the microRNA machinery. These results together suggest that this model could help to delineate the molecular mechanisms for ovarian cancer metastasis, and provide clinically relevant insights to target metastasizing ovarian cancer cells. ©2016 American Association for Cancer Research

Surface cost for each aircraft.

Surface cost for each aircraft.</p

Results of simulation performed using IDDE algorithm.

<p>Results of simulation performed using IDDE algorithm.</p

External cost resulting from congestion.

<p>External cost resulting from congestion.</p