The range of the Amur leopard (Panthera pardus orientalis) has decreased dramatically over the last 100 years. This species is still under extreme risk of extinction and conservation efforts are rigorous. Understanding the long-term dynamics of the population decline would be helpful to offer insight into the mechanism behind the decline and endangerment and improve conservation perspectives an...

OBJECTIVES Research on age-related changes in personal networks has found compelling evidence for socioemotional selectivity theory and exchange theory holding that older adults experience a decline in less emotionally close nonkin relations as they age. However, recent societal developments are likely to have increased the salience of nonkin relations. We hypothesize that age-related decline i...

OBJECTIVE To compare trends in mortality rates from cardiovascular diseases (CVD), ischemic heart diseases (IHD) and cerebrovascular diseases (CBVD) in the States of Rio de Janeiro (RJ), São Paulo (SP) and Rio Grande do Sul (RS) and respective capitals from 1980 to 1999. METHODS Data regarding CVD deaths were obtained from Datasus, and those regarding populations were obtained from IBGE. Crud...

Populations are ageing, with changes in the living arrangements of the elderly occurring in most countries, as a result of lower fertility, higher mobility, changing attitudes about family structure and function, and increasing life expectancy, especially mortality declines in later life. The population of China, which consists of more than two fifths of the world total, is ageing at an extraor...

Following a predicted decline in water resources in the Mediterranean Basin, we used reaction-diffusion equations to gain a better understanding of expected changes in properties of vegetation patterns that evolve along the rainfall transition between semi-arid and arid rainfall regions. Two types of scenarios were investigated: the first, a discrete scenario, where the potential consequences o...

In the last decades, a number of studies based on historical records revealed the diversity loss in the oceans and human-induced changes to marine ecosystems. These studies have improved our understanding of the human impacts in the oceans. They also drew attention to the shifting baseline syndrome and the importance of assessing appropriate sources of data in order to build the most reliable e...

BACKGROUND Given previous findings of adverse health outcomes associated with the E4 allele, data from a biracial community sample of older adults were used to determine whether functional decline is associated with the apolipoprotein E (APOE) E4 allele. METHODS In 1986, a stratified random household sample of community residents 65 years of age and older (n = 4162) formed the Duke Establishe...

Edith Penrose was one of the first scholars to point out that firms may need to rely on research joint ventures (RJVs) to acquire access to resources that can help them achieve and sustain a competitive advantage. We estimate an econometric model of the propensity of firms to disclose their intension to engage in RJVs, in order to explain the recent precipitous decline in RJVs filed with the U....

Frontal contributions to cognitive decline in aging were explored using functional MRI. Frontal regions active in younger adults during self-initiated (intentional) memory encoding were under-recruited in older adults. Older adults showed less activity in anterior-ventral regions associated with controlled use of semantic information. Under-recruitment was reversed by requiring semantic elabora...