Clonal expansion of sequence type (ST-)5 and emergence of ST-7 in serogroup A meningococci, Africa.

One hundred four serogroup A meningococci in our collection, isolated in Africa from 1988 to 1999, were characterized by multilocus sequence typing (MLST). Our results and data from the Internet indicate that sequence type 5 (ST-5) strains were responsible for most of African outbreaks and sporadic cases during this period. In 1995, a new clone, characterized by ST-7 sequence, emerged and was responsible for severe outbreaks in Chad (1998) and Sudan (1999). MLST and epidemiologic data indicate that ST-5 and ST-7 represent two virulent clones. These two STs, which belong to subgroup III, differ only in the pgm locus: allele pgm3 is characteristic for ST-5 and allele pgm19 for ST-7. Subgroup III strains were responsible for two pandemics in the 1960s and 1980s. Our data show that the third subgroup III pandemic has now reached Africa

Trading Efficiency of Fund Families: Impact on Fund Performance and Investment Behavior

Mutual funds are part of larger organizations, which make decisions with consequences for all their member funds. This study examines how the efficiency of trading desks operated by fund families affects the performance and trading of affiliated funds. We introduce a novel approach to measure the efficiency of trading desks, which allows for comparisons across families with different investable universes. By operating efficient trading desks, which reduce trading costs, fund families improve the performance of their funds significantly. Furthermore, the lower trading costs resulting from more efficient trading desks enable mutual funds to trade more and hold less liquid portfolios

Genome-wide association analysis of dementia and its clinical endophenotypes reveal novel loci associated with Alzheimer's disease and three causality networks: The GR@ACE project

INTRODUCTION: Large variability among Alzheimer's disease (AD) cases might impact genetic discoveries and complicate dissection of underlying biological pathways. METHODS: Genome Research at Fundacio ACE (GR@ACE) is a genome-wide study of dementia and its clinical endophenotypes, defined based on AD's clinical certainty and vascular burden. We assessed the impact of known AD loci across endophenotypes to generate loci categories. We incorporated gene coexpression data and conducted pathway analysis per category. Finally, to evaluate the effect of heterogeneity in genetic studies, GR@ACE series were meta-analyzed with additional genome-wide association study data sets. RESULTS: We classified known AD loci into three categories, which might reflect the disease clinical heterogeneity. Vascular processes were only detected as a causal mechanism in probable AD. The meta-analysis strategy revealed the ANKRD31-rs4704171 and NDUFAF6-rs10098778 and confirmed SCIMP-rs7225151 and CD33-rs3865444. DISCUSSION: The regulation of vasculature is a prominent causal component of probable AD. GR@ACE meta-analysis revealed novel AD genetic signals, strongly driven by the presence of clinical heterogeneity in the AD series

Forecasting Bond Risk Premia Using Technical Analysis

This paper is selected as one of the Top Ten Paper in Forecasting in SSRN

Returns to Investors in Stocks in New Industries

We examine the returns to investors in publicly traded stock in new industries. We examine data from the United States on sellers of own-brand personal computers, airlines and airplane manufacturers, automobile manufacturers, railroads, and telegraphs. We find that a relatively small number of companies generate outstanding returns and many firms fail. Firms in new industries typically have high volatility of individual stocks' returns. Compared with indexes for the same period, expected returns of firms are higher for two industries, lower for one industry and roughly the same for two industries. Portfolios of firms in new industries generally have lower Sharpe ratios than the overall market

Creative Destruction and Asset Prices

This paper introduces Schumpeter's idea of creative destruction into asset pricing. The key point of our model is that small and value firms are more likely destroyed during technological revolutions, resulting into higher expected returns for these stocks. A two-factor model including market return and patent activity growth - the proxy for creative destruction risk - accounts for a large portion of the cross-sectional variation of size and book-to-market sorted portfolios and prices HML and SMB. The expected return difference between assets with the highest and lowest exposure to creative destruction risk amounts to 8.6 percent annually