The influence of biological rhythms on host–parasite interactions

Biological rhythms, from circadian control of cellular processes to annual cycles in life history, are a main structural element of biology. Biological rhythms are considered adaptive because they enable organisms to partition activities to cope with, and take advantage of, predictable fluctuations in environmental conditions. A flourishing area of immunology is uncovering rhythms in the immune system of animals, including humans. Given the temporal structure of immunity, and rhythms in parasite activity and disease incidence, we propose that the intersection of chronobiology, disease ecology, and evolutionary biology holds the key to understanding host–parasite interactions. Here, we review host–parasite interactions while explicitly considering biological rhythms, and propose that rhythms: influence within-host infection dynamics and transmission between hosts, might account for diel and annual periodicity in host–parasite systems, and can lead to a host–parasite arms race in the temporal domain

Aerospace medicine and biology: A continuing bibliography with indexes, supplement 128, May 1974

This special bibliography lists 282 reports, articles, and other documents introduced into the NASA scientific and technical information system in April 1974

Observable Persistent Effects of Habitat Management Efforts in the Ozark Highlands After 10 Years

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were used to investigate the impact of each management action separately (Burn or Cut) and in combination (Burn and Cut) relative to unaltered control plots. Measurements were compared between pre-treatment, post-treatment, and 10-years post-treatment time points. I found that a 10-year lapse in management resulted in a complete return to pre-treatment values in overstory density. I also saw a decline below pre-treatment values in understory density and Peromyscus density. Analysis of light availability at the forest floor revealed a persistent effect of treatment. I conclude that while initial treatment was effective, 10 years between management events is too infrequent to achieve the desired long-term changes within my study system. More frequent management may be more effective in meeting the management goals for this Ozark system

Scientific publications of the Bioscience Program Division. Volume II - Environmental biology

Environmental biology bibliography, including citations on biochemistry, radiobiology, and bioinstrumentatio

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 192

This bibliography lists 247 reports, articles, and other documents introduced into the NASA scientific and technical information system in March 1979

Modelling the effects of ionising radiation on a vole population from the Chernobyl Red forest in an ecological context

A novel mathematical model was developed to study the historical effects of ionising radiation from the 1986 Chernobyl accident on a vole population. The model uses an ecosystem approach combining radiation damages and repair, life history and ecological interactions. The influence of reproduction, mortality and factors such as ecosystem resource, spatial heterogeneity and migration are included. Radiation-induced damages are represented by a radiosensitive ‘repairing pool’ mediating between healthy, damaged and radio-adapted animals. The endpoints of the model are repairable radiation damage (morbidity), impairment of reproductive ability and mortality. The focus of the model is the Red Forest, an area some 3 km west of the Chernobyl Nuclear Power Plant. We simulated ecosystem effects of both current exposures and historical doses, including transgenerational effects and adaptation. The results highlight the primary role of animal mobility in stabilising the vole population after the accident, the importance of ecosystem recovery, the time evolution of the repairing and fecundity pools and the impact of adaptation on population sustainability. Using this model, we found dose rate tipping points for mortality and morbidity, along with a limiting migration rate for population survival and the limiting size of the most contaminated region not entailing loss of survival. Our ecosystem approach to radioecological modelling enables an exploration of the impact of radiation in an ecological context, consistent with the available observations. Model predictions indicate that population sensitivity in our exposure scenario does not contradict the benchmarks currently considered in risk assessments for wildlife. The model can be used to support advice on the extent to which historical doses and other ecological factors may influence different exposure modelling scenarios. The approach could easily be adapted to accommodate other stressors, thereby contributing to the evaluation of the regulatory benchmarks used in non-radiological risk assessment

Proceedings: Abstracts of Papers, 83rd Annual Meeting of the Virginia Academy of Science

Abstracts of the papers presented at the 83rd Annual Meeting of the Virginia Academy of Science, May 17-20, 2005, James Madison University, Harrisonburg, Virginia

The Life Cycle of Toxoplasma gondii in the Natural Environment

Chapitre 1International audienc

Proceedings of the 95th Annual Virginia Academy of Science Meeting, 2017

Full proceedings of the 95th Annual Virginia Academy of Science Meeting, May 17-19, 2017, at Virginia Commonwealth University, Richmond, VA