Ovarian volume throughout life : a validated normative model

The measurement of ovarian volume has been shown to be a useful indirect indicator of the ovarian reserve in women of reproductive age, in the diagnosis and management of a number of disorders of puberty and adult reproductive function, and is under investigation as a screening tool for ovarian cancer. To date there is no normative model of ovarian volume throughout life. By searching the published literature for ovarian volume in healthy females, and using our own data from multiple sources (combined n = 59,994) we have generated and robustly validated the first model of ovarian volume from conception to 82 years of age. This model shows that 69% of the variation in ovarian volume is due to age alone. We have shown that in the average case ovarian volume rises from 0.7 mL (95% CI 0.4–1.1 mL) at 2 years of age to a peak of 7.7 mL (95% CI 6.5–9.2 mL) at 20 years of age with a subsequent decline to about 2.8 mL (95% CI 2.7–2.9 mL) at the menopause and smaller volumes thereafter. Our model allows us to generate normal values and ranges for ovarian volume throughout life. This is the first validated normative model of ovarian volume from conception to old age; it will be of use in the diagnosis and management of a number of diverse gynaecological and reproductive conditions in females from birth to menopause and beyond.Publisher PDFPeer reviewe

Evolution of Soil, Ecosystem, and Critical Zone Research at the USDA FS Calhoun Experimental Forest

The US Department of Agriculture (USDA) Forest Service Calhoun Experimental Forest was organized in 1947 on the southern Piedmont to engage in research that today is called restoration ecology, to improve soils, forests, and watersheds in a region that had been severely degraded by nearly 150 years farming. Today, this 2,050-ha research forest is managed by the Sumter National Forest and Southern Research Station. In the early 1960s, the Calhoun Experimental Forest was closed as a base of scientific operations making way for a new laboratory in Research Triangle Park, NC. Many papers were written during the Calhoun’s 15 years of existence, papers that document how land-use history creates a complex of environmental forcings that are hard to unwind. One Calhoun field experiment remains active, however, and over nearly six decades has become a model for the study of soil and ecosystem change on timescales of decades. The experiment contributes greatly to our understanding of the effects of acid atmospheric deposition on soils, forests, and waters and of decadel changes in carbon and nutrient cycling in soils and forests. Perhaps the long-term experiment’s major contribution is its clear demonstration that soils are highly dynamic systems on timescales of decades and that this dynamism involves both surface and deep subsoils. The on-going experiment’s success is attributed to relatively simple experimental design, ample plot replication, rigorous (but not too arduous) protocol for resampling and archiving, and to its ability to address changing scientific and management priorities that are important to society and the environment. In the last decade, the experiment has become a platform for research and education that explore basic and applied science. As this manuscript goes to press, the Calhoun Experimental Forest has been designated to become one of the National Science Foundation’s national Critical Zone (CZ) Observatories, a development that will allow researchers to, return to the questions that originated the Calhoun Experimental Forest in the first place: how and why severely disturbed landscapes evolve through time