The Importance of Asset Allocation and Active Management for Canadian Mutual Funds

Several different factors, including asset allocation policy, active portfolio management and market movements affect the return of a mutual fund. Existing studies test the relative importance of asset allocation policy and active management in explaining the variability of performance. In this paper, we use data for the period 2000-2010 to test the factors\u27 role in determining performance of Canadian equity funds, balanced funds and international funds. The results show that asset allocation policy has the same level of explanatory power as that of active management, with slightly difference among funds of different investment styles

Probing the electroweak symmetry breaking history with Gravitational waves

We perform a three dimensional lattice simulation of the electroweak symmetry breaking process through a two-step phase transition, where one of the two steps is a first order phase transition. Our results show that: 1) when the electroweak symmetry breaking is driven by the beyond Standard Model sector around $\sim \mathcal{O}(10^{2-3})$ GeV, the gravitational wave spectra produced from the phase transitions are of broken power-law double-peak shapes; 2) when the electroweak symmetry breaking is induced by a first-order phase transition of a high-scale global U(1) theory, cosmic strings can form and then disappear through particle radiation, and the yielded gravitational wave spectra are of plateau shapes. The two scenarios can be distinguished through probing gravitational wave spectra. Our study suggests that the stochastic gravitational waves provide an alternative way to probe the beyond Standard Model sector relevant to the electroweak symmetry breaking pattern in the early Universe.Comment: 9 pages, 8 figures, comments welcome

Effect of Cl/S and Na interaction on ash deposition mechanism at the inlet of Shell gasifier syngas cooler

The Shell dry pulverized coal pressurized gasification is one of the important technologies for the clean and efficient utilization of coal. Ash deposition at the inlet of the syngas cooler caused by alkali metal compounds is the main reason for the unscheduled shutdown of the gasifier. The effect of Cl/S and Na interaction on ash deposition is studied by adding different contents of Na, Cl and S to the raw fly ash. The ash deposition experiment is conducted by using the deposition probe in the self-built high temperature vertical furnace. The ash deposition behavior is studied by separating it into inner layer and the outer layer. The mass changes of the inner and outer ash deposits are discussed. The physicochemical properties of the inner and outer ash deposits are compared and analyzed by means of ICP-MS, IC, SEM-EDS and XRD. The influence of the interaction among elements such as Cl, S and Fe on the ash deposition behavior is obtained. The results show that the mass of inner ash deposits increases with time. The addition of compounds containing S reduces the mass of both the inner and outer ash deposits. And the mass of outer ash deposits decreases with time. The Na in the form of aluminosilicate promotes the growth of ash deposit in the outer layer. The Cl is enriched in the initial viscous layer in the form of alkali metal chloride. The existence of S slows down the pipeline dust deposition. In the presence of Cl and S, the Fe reacts with Si, Al and Na and generates a variety of low temperature eutectic, promoting the melting of inner and outer ash deposition. The formation mechanism of ash deposit at the inlet of the Shell gasifier syngas cooler is as follows: firstly, under the interaction among the Na, Cl, Si and Al, the alkali metal chloride and aluminosilicate deposit in the inner layer. At the same time, the existence of Cl and S combine with Fe and Na to form Fe-O-Si, Fe-O-S and Fe-Na-O-Al-S eutectic. Then, the melting of aluminosilicate and various low temperature eutectic increase the size of ash particles and promote the further growth of ash deposition

Quantum chemical calculation study on the thermal decomposition of electrolyte during lithium-ion battery thermal runaway

Understanding the behavior of lithium-ion battery electrolytes during thermal runaway is essential for designing safer batteries. However, current reports on electrolyte decomposition behaviors often focus on reactions with electrode materials. Herein we use quantum chemical calculations to develop a model for the thermal decomposition mechanism of electrolytes under both electrolyte and ambient atmosphere conditions. The thermal stability is found to be associated with the dielectric constants of electrolyte constituents. Within the electrolyte, the solvation effects between molecules increase electrolyte stability, making thermal decomposition a more difficult process. Furthermore, Li+ is observed to facilitate electrolyte thermal decomposition, as the energy required for the thermal decomposition reactions of molecules decreases when they are bonded with Li+. It is hoped that this study will offer a theoretical basis for understanding the complex reactions occurring during thermal runaway events

Baiji genomes reveal low genetic variability and new insights into secondary aquatic adaptations

The baiji, or Yangtze River dolphin (Lipotes vexillifer), is a flagship species for the conservation of aquatic animals and ecosystems in the Yangtze River of China; however, this species has now been recognized as functionally extinct. Here we report a high-quality draft genome and three re-sequenced genomes of L. vexillifer using Illumina short-read sequencing technology. Comparative genomic analyses reveal that cetaceans have a slow molecular clock and molecular adaptations to their aquatic lifestyle. We also find a significantly lower number of heterozygous single nucleotide polymorphisms in the baiji compared to all other mammalian genomes reported thus far. A reconstruction of the demographic history of the baiji indicates that a bottleneck occurred near the end of the last deglaciation, a time coinciding with a rapid decrease in temperature and the rise of eustatic sea level

Finishing the euchromatic sequence of the human genome

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

A Novel Approach of Slope Detection Combined with Lv’s Distribution for Airborne SAR Imagery of Fast Moving Targets

This paper presents a fast SAR imagery algorithm for Ground Moving Target Imaging (GMTIm) based on the slope detection strategy combined with Time-Frequency Representation (TFR), which is known as Lv’s Distribution (LVD). This fast imagery algorithm focuses on the solution of the ambiguity problems and relevant heavy computing load in SAR imagery. Firstly, according to the relationship between the slope of the range walk trajectory and the cross-track velocity of moving target, a new high-efficiency slope detection strategy based on gradient and level-line angle is presented in the image domain. Then, the Doppler centroid shift induced by cross-track velocity can also be obtained. Secondly, owing to the cross-track velocity estimated before, the Range Walk Migration Correction (RWMC) can be performed to concentrate the echo response of the moving target into a single range cell. Finally, due to the superior performance in representing multi-component Linear Frequency Modulation (LFM) signal, LVD is adopted here to represent the Doppler chirp rate of multiple moving targets in a Doppler Centroid Frequency and Chirp Rate domain (CFCR). The performance of the proposed algorithm is evaluated in terms of superiority and effectiveness using simulations, and the comparison between the proposed algorithm and the other conventional algorithms is also presented