26 research outputs found
Synthesis of C(3) Benzofuran-Derived Bisaryl Quaternary Centers: Approaches to Diazonamide A
Two complementary strategies for the synthesis of the diazonamide A bisaryl quaternary center are described. The first strategy relies upon an extremely facile tandem cyclopropanation/ring-opening sequence, which has proven amenable to chiral catalysis to provide enantioenriched material. The second strategy relies upon a more concise alkylation route ideal for material advancement
Crisis and recovery in the wake of super-salient news: Who moves markets?
Abstract We compare reactions in the prices and trading patterns of common stocks and closed-end funds, which have substantially di¤erent investor clienteles, to the September 11, 2001 terrorist attacks. Even in assets with institutional buying, retail investor trading moved prices signi…cantly lower. Although greater salience has been shown to reduce underreaction to news, we conclude the extreme salience of this event resulted in overreaction. Subsequent reversals were substantially security-speci…c and therefore not due simply to improvement in general sentiment. Consistent with microstructure theory, the speed of reversals depended signi…cantly on the relative quality and availability of information about fundamental values. terrorist attacks. Even in assets with net institutional buying, retail investor trading moved prices signi…cantly lower. Although greater salience has been shown to reduce underreaction to news, we conclude the extreme salience of this event resulted in overreaction. Subsequent reversals were substantially security-speci…c and therefore not due simply to improvement in general sentiment. Consistent with microstructure theory, the speed of reversals depended signi…cantly on the relative quality and availability of information about fundamental values. JEL classi…cations: G12, G1
Synthesis of C(3) Benzofuran-Derived Bisaryl Quaternary Centers: Approaches to Diazonamide A
Neocortical Axon Arbors Trade-off Material and Conduction Delay Conservation
The brain contains a complex network of axons rapidly communicating information between billions of synaptically connected neurons. The morphology of individual axons, therefore, defines the course of information flow within the brain. More than a century ago, Ramón y Cajal proposed that conservation laws to save material (wire) length and limit conduction delay regulate the design of individual axon arbors in cerebral cortex. Yet the spatial and temporal communication costs of single neocortical axons remain undefined. Here, using reconstructions of in vivo labelled excitatory spiny cell and inhibitory basket cell intracortical axons combined with a variety of graph optimization algorithms, we empirically investigated Cajal's conservation laws in cerebral cortex for whole three-dimensional (3D) axon arbors, to our knowledge the first study of its kind. We found intracortical axons were significantly longer than optimal. The temporal cost of cortical axons was also suboptimal though far superior to wire-minimized arbors. We discovered that cortical axon branching appears to promote a low temporal dispersion of axonal latencies and a tight relationship between cortical distance and axonal latency. In addition, inhibitory basket cell axonal latencies may occur within a much narrower temporal window than excitatory spiny cell axons, which may help boost signal detection. Thus, to optimize neuronal network communication we find that a modest excess of axonal wire is traded-off to enhance arbor temporal economy and precision. Our results offer insight into the principles of brain organization and communication in and development of grey matter, where temporal precision is a crucial prerequisite for coincidence detection, synchronization and rapid network oscillations
Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease
BACKGROUND:
Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes.
METHODS:
We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization.
RESULTS:
During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events.
CONCLUSIONS:
Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)
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What Can “Nine‐Eleven” Tell Us about Closed‐end Fund Discounts and Investor Sentiment?
Who Moves Markets in a Sudden Marketwide Crisis? Evidence from 9/11
We compare reactions in the prices and trading patterns of common stocks and closed-end funds (CEFs), securities with substantially different investor clienteles, to the Sept. 11, 2001 terrorist attacks. When the market reopened 6 days later, retail investors sold and there were sharp price declines, even in assets with net institutional buying. In the subsequent 2 weeks, price reversals were substantially security specific and thus not simply due to improved systematic sentiment. Consistent with microstructure theory, comparisons between CEFs and common stocks show the speed of these reversals depended significantly on the relative quality and availability of information about fundamental values
Who moves markets in a sudden market-wide crisis? Evidence from nine-eleven
Abstract We compare reactions in the prices and trading patterns of common stocks and closed-end funds (CEFs), which have substantially di¤erent investor clienteles, to the September 11, 2001 terrorist attacks. When the market reopened six days later, retail investors sold and there were sharp price declines-even in assets with net institutional buying. In the subsequent two weeks, price reversals were substantially security-speci…c and thus not simply due to improved systematic sentiment. Consistent with microstructure theory, comparisons between CEFs and common stocks show the speed of these reversals depended signi…cantly on the relative quality and availability of information about fundamental values