Mixed ether bath for electrodeposition of aluminum

Anisole added to the bath mixture improves Brenner aluminum plating bath technique. Mixture has lower bath vapor-pressure and the electro-deposits obtained have greater physical strength than deposits from the Brenner bath

Research and development of electroformed aluminum solar cell contacts and interconnects Periodic progress report, 5 Jun. - 4 Oct. 1969

Development of electroformed aluminum solar cell contacts and interconnect

Cloning and expression of the Propionibacterium shermanii methylmalonyl-CoA epimerase gene in Escherichia coli : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry at Massey University

Genomic DNA was isolated from Propionibacterium shermanii (52W). A 454 bp DNA fragment coding for the methylmalonyl-CoA epimerase (EC 5.1.99.1, subsequently referred to as epimerase) was amplified from genomic DNA by the polymerase chain reaction using primers designed from the known DNA sequence of the gene. The P. shermanii epimerase gene was ligated into the 2.47 kbp expression vector pT7-7. The ligation reaction mixture was transformed into electroporation competent E.coli XL1-Blue cells. Plasmid DNA prepared from several transformants was analysed, by agarose gel electrophoresis of restriction enzyme digestions, and transformed into E.coli SRP84/pGP1-2 cells to identify potential epimerase expression constructs (pTEEX) by heat shock induction. The insert DNA of one of the putative pTEEX epimerase constructs was fully sequenced and shown to be identical to the known DNA sequence of the epimerase gene described by Davis (1987). Using the sequenced expression construct pTEEX, recombinant epimerase was expressed to 20-35% of the total cell protein in the protease deficient E.coli strain SRP84 using the dual plasmid expression system of Tabor and Richardson (1985). The recombinant epimerase was ~95-100% soluble in E.coli. The recombinant epimerase and the 'wild-type' epimerase produced by P. shermanii were purified using the procedures developed for the 'wild-type' epimerase. The addition of a heat-treatment step (70°C for 15 min) early in the purification of the recombinant enzyme successfully exploited the unusually high thermostability of the epimerase protein. The epimerase protein was found to have an anomalously low electrophoretic mobility in a modified Laemmli discontinuous Tris-glycine alkaline buffer system for SDS-PAGE gels compared to the Weber and Osborn continuous phosphate buffer system. Using the latter system, a subunit molecular weight of 16.6 kDa was obtained. This is consistent with the molecular weight of 16.72 kDa (methionine on) calculated from the inferred amino acid sequence. The N-terminal sequence of the purified 'wild-type' and recombinant epimerases were identical although only half of N-terminal methionine residues were removed from the recombinant protein. The subunit molecular weight, specific activity, activation by divalent metal ions and behaviour in crystallization trials of the 'wild-type' and recombinant epimerases were very similar. Recombinant epimerase crystals were grown in a buffer containing 0.2 M ammonium acetate and 0.1 M citrate, pH 5.6, containing 30% PEG 4000 as precipitant. These crystals were relatively poorly ordered and diffracted to only 4.5 Ǻ resolution, but crystals of the recombinant epimerase that diffract to 2.6Ǻ can be grown under appropriate conditions

An Empirical Study of Asian Stock Volatility Using Stochastic Volatility Factor Model: Factor Analysis and Forecasting

This paper is an empirical study of Asian stock volatility using stochastic volatility factor (SVF) model of Cipollini and Kapetanios (2005). We adopt their approach to carry out factor analysis and to forecast volatility. Our results show some Asian factors exhibit long memory that is in line with existing empirical findings in financial volatility. However, their local-factor SVF model is not powerful enough in forecasting Asian volatility. This has led us to propose an extension to a multi-factor SVF model. We also discuss how to produce forecast using this multi-factor model.Stochastic volatility, Local-factor model, Multi-factor model, Principal components, Forecasting

Geometric Registration of High-genus Surfaces

This paper presents a method to obtain geometric registrations between high-genus ($g\geq 1$) surfaces. Surface registration between simple surfaces, such as simply-connected open surfaces, has been well studied. However, very few works have been carried out for the registration of high-genus surfaces. The high-genus topology of the surface poses great challenge for surface registration. A possible approach is to partition surfaces into simply-connected patches and registration is done patch by patch. Consistent cuts are required, which are usually difficult to obtain and prone to error. In this work, we propose an effective way to obtain geometric registration between high-genus surfaces without introducing consistent cuts. The key idea is to conformally parameterize the surface into its universal covering space, which is either the Euclidean plane or the hyperbolic disk embedded in $\mathbb{R}^2$. Registration can then be done on the universal covering space by minimizing a shape mismatching energy measuring the geometric dissimilarity between the two surfaces. Our proposed algorithm effectively computes a smooth registration between high-genus surfaces that matches geometric information as much as possible. The algorithm can also be applied to find a smooth and bijective registration minimizing any general energy functionals. Numerical experiments on high-genus surface data show that our proposed method is effective for registering high-genus surfaces with geometric matching. We also applied the method to register anatomical structures for medical imaging, which demonstrates the usefulness of the proposed algorithm

A Genetic Algorithm Tool (splicer) for Complex Scheduling Problems and the Space Station Freedom Resupply Problem

The Space Station Freedom will require the supply of items in a regular fashion. A schedule for the delivery of these items is not easy to design due to the large span of time involved and the possibility of cancellations and changes in shuttle flights. This paper presents the basic concepts of a genetic algorithm model, and also presents the results of an effort to apply genetic algorithms to the design of propellant resupply schedules. As part of this effort, a simple simulator and an encoding by which a genetic algorithm can find near optimal schedules have been developed. Additionally, this paper proposes ways in which robust schedules, i.e., schedules that can tolerate small changes, can be found using genetic algorithms

Mobile transporter path planning

The use of a genetic algorithm (GA) for solving the mobile transporter path planning problem is investigated. The mobile transporter is a traveling robotic vehicle proposed for the space station which must be able to reach any point of the structure autonomously. Elements of the genetic algorithm are explored in both a theoretical and experimental sense. Specifically, double crossover, greedy crossover, and tournament selection techniques are examined. Additionally, the use of local optimization techniques working in concert with the GA are also explored. Recent developments in genetic algorithm theory are shown to be particularly effective in a path planning problem domain, though problem areas can be cited which require more research