BACKGROUND Stresses like dietary restriction or various toxins increase lifespan in taxa as diverse as yeast, Caenorhabditis elegans, Drosophila and rats, by triggering physiological responses that also tend to delay reproduction. Food odors can reverse the effects of dietary restriction, showing that key mechanisms respond to information, not just resources. Such environmental cues can predict...

BACKGROUND Cardiovascular diseases (CVD) are the leading causes of death in our population. There was a progressive decrease in mortality due to CVD up to 2005. OBJECTIVE To update the trends in mortality from cardiovascular diseases in Brazil and in the metropolitan region of São Paulo (MRSP) from 1990 to 2009. METHODS Mortality and population data were obtained from the Brazilian Institut...

in order to study the effects of planting date and sugar beet cultivars on infection to curly top virus, vector population, damping off, root rot, and sugar yield, an experiment was conducted in mobarakeh region during 1999-2000 in a split plot design. the main factor was three planting dates and sub factor was six sugar beet cultivars: ic1 as a susceptible cultivar to beet curly top, t41r, 723...

Determining which demographic and ecological parameters contribute to variation in population growth rate is crucial to understanding the dynamics of declining populations. This study aimed to evaluate the magnitude and mechanisms of an apparent major decline in an Atlantic Puffin Fratercula arctica population. This was achieved using a 27-year dataset to estimate changes in population size and...

We explore the minimal conditions for sustainable cooperation on a spatially distributed population of memoryless, unconditional strategies (cooperators and defectors) in presence of unbiased, non-contingent mobility in the context of the Prisoner's Dilemma game. We find that cooperative behavior is not only possible but may even be enhanced by such an "always-move" rule, when compared with the...

background: natural killer (nk) cells are the effector cells of innate immunity that respond to infection and tumor. interactions between killer cell immunoglobulin like receptors (kir) and human leukocyte antigen (hla) class i molecules regulate nk cells responses to eliminate infected and transformed cells. objective: to investigate the impact of kir genes, hla ligand genes, and kir-hla combi...

over the past two decades, shanghai, the largest megacity in china, has been coping with unprecedented growth of its economy and population while overcoming previous underinvestment in the health system by the central and local governments. we study the evolution of shanghai’s healthcare system by analyzing “avoidable mortality” (am) – deaths amenable to public health and healthcare interventio...