Microcharcoal concentration and elongation, and age model of sediment core MD96-2098

Although grassland and savanna occupy only a quarter of the world's vegetation, burning in these ecosystems accounts for roughly half the global carbon emissions from fire. However, the processes that govern changes in grassland burning are poorly understood, particularly on time scales beyond satellite records. We analyzed microcharcoal, sediments, and geochemistry in a high-resolution marine sediment core off Namibia to identify the processes that have controlled biomass burning in southern African grassland ecosystems under large, multimillennial-scale climate changes. Six fire cycles occurred during the past 170,000 y in southern Africa that correspond both in timing and magnitude to the precessional forcing of north-south shifts in the Intertropical Convergence Zone. Contrary to the conventional expectation that fire increases with higher temperatures and increased drought, we found that wetter and cooler climates cause increased burning in the study region, owing to a shift in rainfall amount and seasonality (and thus vegetation flammability). We also show that charcoal morphology (i.e., the particle's length-to-width ratio) can be used to reconstruct changes in fire activity as well as biome shifts over time. Our results provide essential context for understanding current and future grassland-fire dynamics and their associated carbon emissions.

Distinct spectra of somatic mutations accumulated with age in mouse heart and small intestine

Somatic mutation accumulation has been implicated as a major cause of cancer and aging. By using a transgenic mouse model with a chromosomally integrated lacZ reporter gene, mutational spectra were characterized at young and old age in two organs greatly differing in proliferative activity, i.e., the heart and small intestine. At young age the spectra were nearly identical, mainly consisting of G·C to A·T transitions and 1-bp deletions. At old age, however, distinct patterns of mutations had developed. In small intestine, only point mutations were found to accumulate, including G·C to T·A, G·C to C·G, and A·T to C·G transversions and G·C to A·T transitions. In contrast, in heart about half of the accumulated mutations appeared to be large genome rearrangements, involving up to 34 centimorgans of chromosomal DNA. Virtually all other mutations accumulating in the heart appeared to be G·C to A·T transitions at CpG sites. These results suggest that distinct mechanisms lead to organ-specific genome deterioration and dysfunction at old age.

Measuring Dependency Ratios using National Transfer Accounts. CEPS Working Document No. 420/April 2016

It is now widely recognised that the socio-economic changes that ageing societies will bring about are poorly captured by the traditional demographic dependency ratios (DDRs), such as the old-age dependency ratio that relates the number of people aged 65+ to the working-age population. Future older generations will have increasingly better health and are likely to work longer. By combining population projections and National Transfer Accounts (NTA) data for seven European countries, we project the quantitative impact of ageing on public finances until 2040 and compare it to projected DDRs. We then simulate the public finance impact of changes in three key indicators related to the policy responses to population ageing: net immigration, healthy ageing and longer working lives. We do this by linking age-specific public health transfers and labour market participation rates to changes in mortality. Four main findings emerge: first, the simple old-age dependency ratio overestimates the future public finance challenges faced by the countries studied – significantly so for some countries, e.g. Austria, Finland and Hungary. Second, healthy ageing has a modest effect (on public finances) except in the case of Sweden, where it is substantial. Third, the long-run effect of immigration is well captured by the simple DDR measure if immigrants are similar to the native population. Finally, increasing the length of working lives is central to addressing the public finance challenge of ageing. Extending the length of working lives by three to four years over the next 25 years – equivalent to the increase in life expectancy – severely limits the impact of ageing on public transfers.

Early retirement provisions of pension plans, 1971 /

Cover title.

Health, welfare and pension programs under wage stabilization : report to the Wage Stabilization Board.

Mode of access: Internet.

The operation of the welfare and pension plans disclosure act, January 1, 1959-June 30, 1960.

Reproduced from typewritten copy.

Reporting under the Welfare and Pension Plans Disclosure Act, Public Law 85-836 : effective Jan. 1, 1959, 72 Stat. 997.

"Guide in using plan description and annual report forms prepared by the Secretary of Labor."

An international comparison of pension systems /

Bibliography: p. [41]-[46] (3d group)

[Aging; selected references. Seven pamphlets from the Library of The National Council on the Aging.

A general bibliography on aging, by the Library of the National Committee on the Aging. Recent publications on aging, 1962; a supplement to "A general bibliography on aging". Friendly visiting; selected references. Guardianship and protective services; selected references. Housing for the aged; selected references. Retirement planning; selected references. Rev. ed. The implications of automation and technological development for the employment of older workers: a preliminary selected bibliography, by Norman Sprague.

National Institute on Aging /

Mode of access: Internet.

Portability of pension benefits /

"January 1981."

Pension coverage and vesting among private wage and salary workers, 1979 : preliminary estimates from the 1979 survey of pension plan coverage /

Includes bibliographical references.