Surgical Management of Posterior Circulation Aneurysms: Defining the Role of Microsurgery in Contemporary Endovascular Era

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Total Synthesis of vallartanone A

The research presented herein describes the first enantioselective total syntheses of vallartanone A and its (8R) epimer both starting with propanoic acid and isobutyraldehyde. The key steps involved a proline-catalyzed intermolecular aldol reaction and a second aldol reaction that proceeded with kinetic resolution. It is concluded that the absolute configuration of vallartanone A should be revised to (3S,4S,8S)

A defense of incorrigibility and self-intimation

Master'sMASTER OF ART

Dynamic portfolio rebalancing with lag-optimised trading indicators using SeroFAM and genetic algorithms

Some common technical indicators, such as moving average convergence divergence (MACD), relative strength index (RSI), and MACD histogram (MACDH) are used in technical analyses and stock trading. However, some of them are lagging indicators, affecting the effectiveness in the stock trading and portfolio management. A forecasted MACDH (fMACDH) indicator for predicting next day price by a neuro-fuzzy network, Self-reorganizing Fuzzy Associative Machine (SeroFAM) which has been reported in the prior research work. In order to further reduce the lagging effect, two trading indicators are proposed in this paper: the optimised fMACDH indicator and the fMACDH-fRSI indicator. The optimised fMACDH indicator is derived to extend price forecasting to 1-5 days ahead as the prediction depth, using 1-5 days of historical price data as the input depth. The fMACDH-fRSI indicator is derived by combining the optimized fMACDH indicator and the forecasted RSI (fRSI) indicator. A genetic algorithm (GA) and the fitness functions are designed with the SeroFAM in this paper, which are utilised for optimising parameters of these two proposed indicators. Experiments have been conducted to evaluate and benchmark of the proposed trading indicators optimised by the GA. Two rule-based portfolio rebalancing algorithms are then proposed using the optimised fMACDH trading indicator tuned by the GA: the Tactical Buy and Hold (TBH) and the Rule-Based Business Cycle (RBBC) portfolio rebalancing algorithms. The TBH algorithm takes advantage of relative differences in risk levels to perform rebalancing during trend reversals. The RBBC portfolio rebalancing algorithm takes advantage of the offsets between the business cycles of different market sectors. Experiments have been conducted to evaluate the performance of both algorithms using two sets of portfolios consisting of different assets. The TBH portfolio rebalancing algorithm outperforms the equally weighted portfolio strategy by about 26% - 27%; as well outperforms the Buy and Hold strategy by 5% - 40%. The RBBC portfolio rebalancing algorithm outperforms the equally weighted portfolio strategy by 54% - 55%; it also outperforms 12 out of the 13 assets with the Buy and Hold strategy, by an average performance of about 166%. The results are highly encouraging with consistent performances achieved in dynamic portfolio rebalancing

Arrestin-Mediated Endocytosis of Yeast Plasma Membrane Transporters

Many plasma membrane transporters in yeast are endocytosed in response to excess substrate or certain stresses and degraded in the vacuole. Endocytosis invariably requires ubiquitination by the HECT domain ligase Rsp5. In the cases of the manganese transporter Smf1 and the amino acid transporters Can1, Lyp1 and Mup1 it has been shown that ubiquitination is mediated by arrestin-like adaptor proteins that bind to Rsp5 and recognize specific transporters. As yeast contains a large family of arrestins, this has been suggested as a general model for transporter regulation; however, analysis is complicated by redundancy amongst the arrestins. We have tested this model by removing all the arrestins and examining the requirements for endocytosis of four more transporters, Itr1 (inositol), Hxt6 (glucose), Fur4 (uracil) and Tat2 (tryptophan). This reveals functions for the arrestins Art5/Ygr068c and Art4/Rod1, and additional roles for Art1/Ldb19, Art2/Ecm21 and Art8/Csr2. It also reveals functional redundancy between arrestins and the arrestin-like adaptors Bul1 and Bul2. In addition, we show that delivery to the vacuole often requires multiple additional ubiquitin ligases or adaptors, including the RING domain ligase Pib1, and the adaptors Bsd2, Ear1 and Ssh4, some acting redundantly. We discuss the similarities and differences in the requirements for regulation of different transporters