Do the Largest Firms Grow and Diversify the Fastest? The Case of U.S. Dairies

We analyze growth and diversification of U.S. dairy farms by examining changes in ten size cohorts and new entrants through three successive censuses. We reject Gibrat’s law and the mean reversion hypothesis of growth. Growth rates appear bimodal where the smallest and largest farm cohorts grow fastest. All cohorts diversify but the largest farms do not diversify as rapidly as medium-sized farms. New entrants are generally large, and they diversify more rapidly than comparably-sized incumbents. These data suggest that scale economies persist even for the largest cohort of U.S. dairy farms and scale economies dominate scope economies for large farms.: census, dairy, diversification, growth, scale, scope

Do the Largest Firms Grow the Fastest? The Case of U.S. Dairies

Replaced with revised version of paper 06/29/07.Livestock Production/Industries, Productivity Analysis,

What Does Initial Farm Size Imply About Growth and Diversification?

Recent consolidation in agriculture has shifted production toward fewer but larger farms, reshaping business relationships between farmers, processors, input suppliers, and local communities. We analyze growth and diversification of U.S. corn, wheat, apple, and beef farms by examining longitudinal changes in 10 size cohorts through three successive censuses. We fail to reject Gibrat’s law in apple and wheat industries and the mean reversion hypothesis in beef and corn industries. Apple and wheat farms diversify over time. The findings suggest that scale economies diminish for large farms across all four industries and scope economies dominate scale economies for large apple and wheat farms.diversification, firm growth, Gibrat’s law, longitudinal data, scale economies, scope economies, Agribusiness, Farm Management, Production Economics, Q12,

What does Initial Farm Size Imply About Growth and Diversification?

Recent consolidation in agriculture has shifted production toward fewer but larger farms, reshaping business relationships between farmers, processors, input suppliers, and local communities. We analyze growth and diversification of U.S. corn, wheat, apple, and beef, farms by examining longitudinal changes in ten size cohorts through three successive censuses. We fail to reject Gibrat’s law in apple and wheat industries and the mean reversion hypothesis in beef and corn industries. Apple and wheat farms diversify over time. Findings suggest that scale economies diminish for large farms across all four industries and scope economies dominate scale economies for large apple and wheat farms.firm growth, diversification, scale economies, scope economies, Gibrat’s law, longitudinal data

Farm Growth, Consolidation, and Diversification: Washington Dairy Industry

Farm Management, Q12,

An optical coherence microscope for 3-dimensional imaging in developmental biology

An optical coherence microscope (OCM) has been designed and constructed to acquire 3-dimensional images of highly scattering biological tissue. Volume-rendering software is used to enhance 3-D visualization of the data sets. Lateral resolution of the OCM is 5 mm (FWHM), and the depth resolution is 10 mm (FWHM) in tissue. The design trade-offs for a 3-D OCM are discussed, and the fundamental photon noise limitation is measured and compared with theory. A rotating 3-D image of a frog embryo is presented to illustrate the capabilities of the instrument

From Animaculum to single-molecules : 300 years of the light microscope

Although not laying claim to being the inventor of the light microscope, Antonj van Leeuwenhoek (1632-1723) was arguably the first person to bring this new technological wonder of the age properly to the attention of natural scientists interested in the study of living things (people we might now term 'biologists'). He was a Dutch draper with no formal scientific training. From using magnifying glasses to observe threads in cloth, he went on to develop over 500 simple single lens microscopes (Baker & Leeuwenhoek 1739 Phil. Trans. 41, 503-519. (doi:10.1098/rstl.1739.0085)) which he used to observe many different biological samples. He communicated his finding to the Royal Society in a series of letters (Leeuwenhoek 1800 The select works of Antony Van Leeuwenhoek, containing his microscopical discoveries in many of the works of nature, vol. 1) including the one republished in this edition of Open Biology. Our review here begins with the work of van Leeuwenhoek before summarizing the key developments over the last ca 300 years, which has seen the light microscope evolve from a simple single lens device of van Leeuwenhoek's day into an instrument capable of observing the dynamics of single biological molecules inside living cells, and to tracking every cell nucleus in the development of whole embryos and plants