Two stylized facts about poverty in Africa motivate this article: female-headed households tend to be poorer, and poverty has been falling in the aggregate since the 1990s. These facts raise two questions. First, how have female-headed households fared? Second, what role have they played in Africa's impressive recent aggregate growth and poverty reduction? Using data covering the entire region,...

We make a correction to the calculation of mean seek time in a recent algorithm of intelligently positioned two headed disk systems. We also introduce a new two headed disk system with better mean seek time.

How do tariffs impact gender inequality? Using harmonized household survey and tariff data from 54 low- middle-income countries, this paper shows that protectionism has an anti-female bias. On average, repress the real incomes of female headed households by 0.6 percentage points relative to male ones. Female bear brunt because they derive a smaller share their income spend larger budget on agri...

The Red-headed Woodpecker (Melanerpes erythrocephalus) has experienced strong population declines during the past 3 decades. Using North American Breeding Bird Survey (BBS) and Audubon Christmas Bird Count (CBC) data, we investigated 4 hypotheses that may explain this decline, including: (1) interspecific competition with native Red-bellied Woodpeckers (Melanerpes carolinus) and nonnative Europ...

The bar-headed goose flies over the Himalayan mountains on its migratory route between South and Central Asia, reaching altitudes of up to 9,000 m. We compared control of breathing in this species with that of low-altitude waterfowl by exposing birds to step decreases in inspired O(2) under both poikilocapnic and isocapnic conditions. Bar-headed geese breathed substantially more than both greyl...

Most species of social insects have singly mated queens, but in some species each queen mates with numerous males to create a colony with a genetically diverse worker force. The adaptive significance of polyandry by social insect queens remains an evolutionary puzzle. Using the honeybee (Apis mellifera), we tested the hypothesis that polyandry improves a colony's resistance to disease. We estab...

A 50-year-old man was seen as an outpatient for isolated, minimal and intermittent lower gastrointestinal bleeding. He had a history of well-controlled hypertension and diabetes. During his colonoscopy, a polyp with two heads that shared a common long and large stalk was encountered in the sigmoid colon (Fig. 1A). The heads were approximately 2 cm and 3 cm in size. Because of their overall size...