We apply a new bootstrap statistical technique to examine the performance of the US. open-end, domestic equity mutual fund industry over the 1975 to 2002 period. A bootstrap approach is necessary because the cross sec...
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We apply a new bootstrap statistical technique to examine the performance of the US. open-end, domestic equity mutual fund industry over the 1975 to 2002 period. A bootstrap approach is necessary because the cross section of mutual fund alphas has a complex nonnormal distribution due to heterogeneous risk-taking by funds as well as nonnormalities in individual fund alpha distributions. Our bootstrap approach uncovers findings that differ from many past studies. Specifically, we find that a sizable minority of managers pick stocks well enough to more than cover their costs. Moreover, the superior alphas of these managers persist.
A crude mixture of thermostable peptides extracted from porcine duodenum was fractionated by electrofocusing. A neutral fraction, different from the basic fractions of GIP [gastric inhibitory peptide], VIP [vasoactive...
A crude mixture of thermostable peptides extracted from porcine duodenum was fractionated by electrofocusing. A neutral fraction, different from the basic fractions of GIP [gastric inhibitory peptide], VIP [vasoactive intestinal polypeptide], PHI [porcine intestinal peptide] and CCK [cholecystokinin] promoted insulin secretion when injected in vivo to normal rats. This neutral fraction, extracted from the crude mixture by chromatography, stimulated insulin output from an isolated rat pancreas and enhanced glucose-induced insulin release. The insulinotropic effect of this partially purified duodeno-jejunal material disappeared following purified duodeno-jejunal material disappeared following digestion with trypsin. The insulin-releasing activity corresponded to a compound of MW higher than that of insulin (i.e. higher than 6000). No GIP-like immunoreactivity was found in this neutral fraction indicating that the active peptide(s) are GIP-related compounds. Apparently porcine duodenum contains an incretin activity different from that of the insulinotropic factors already reported.
Infection of the aorta continues to be a clinical challenge with high morbidity and mortality. The incidence varies between 0.6 and 2.6%. There has been a steady increase in graft infections, especially endograft infe...
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Infection of the aorta continues to be a clinical challenge with high morbidity and mortality. The incidence varies between 0.6 and 2.6%. There has been a steady increase in graft infections, especially endograft infections, due to increased procedures (0.2 to 5%). Staphylococcus species remains the most common organism;however, gram-negative and rare causative agents are also reported. The clinical presentation can be very diverse and a high degree of suspicion is necessary to diagnose them. Sometimes, they may present as an emergency with rupture or fistulation. Diagnosis is based on a triad of clinical features, microbial cultures and imaging. Culture-specific antibiotics are mandatory during the entire course, but seldom cure alone. Surgical management remains the standard of care and involves an integrated approach involving debridement, reconstruction and use of adjuncts. Various aortic substitutes have been described with advantages and limitations. Pericardial tube grafts have emerged as a good option. Endo-vascular options are practiced mostly as a bridge to definitive surgery. A small role for conservative management is described. Aortic fistulation to the gut and airway carries a very high mortality. There are no large series in the literature to define guideline-directed treatment and most often it is a customized solution. The 30-day mortality remains close to 30%. Outcomes depend on multiple factors including patient's age, the timing of presentation, diagnosis, causative organism, host status and the treatment strategy adopted.
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