Ancient mtDNA analysis of early 16(th) century Caribbean cattle provides insight into founding populations of New World creole cattle breeds

The Columbian Exchange resulted in a widespread movement of humans, plants and animals between the Old and New Worlds. The late 15^th to early 16^th century transfer of cattle from the Iberian Peninsula and Canary Islands to the Caribbean laid the foundation for the development of American creole cattle (Bos taurus) breeds. Genetic analyses of modern cattle from the Americas reveal a mixed ancestry of European, African and Indian origins. Recent debate in the genetic literature centers on the ‘African’ haplogroup T1 and its subhaplogroups, alternatively tying their origins to the initial Spanish herds, and/or from subsequent movements of taurine cattle through the African slave trade. We examine this problem through ancient DNA analysis of early 16^th century cattle bone from Sevilla la Nueva, the first Spanish colony in Jamaica. In spite of poor DNA preservation, both T3 and T1 haplogroups were identified in the cattle remains, confirming the presence of T1 in the earliest Spanish herds. The absence, however, of “African-derived American” haplotypes (AA/T1c1a1) in the Sevilla la Nueva sample, leaves open the origins of this sub-haplogroup in contemporary Caribbean cattle.

Production of trichothecene mycotoxins by Fusarium graminearum and Fusarium culmorum on barley and wheat

Wheat cultivars (Stoa, MN87150, SuMai-3, YMI-6, Wheaton) and barley cultivars (Robust, Excel, Chevron, M69) were inoculated in the field with isolates of Fusarium graminearum and F. culmorum. The disease (Fusarium head blight) kernels were analyzed for deoxynivalenol (DON), 15-acetyldeoxynivalenol (15-ADON) and nivalenol (NIV). F. culmorum produced all three trichothecenes on all cultivars tested whereas F. graminearum only produced DON and 15-ADON. There was no well defined correlation between DON production in the host and resistance although the data tended to favor SuMai-3 as having definitive resistance to both F. graminearum and F. culmorum.

The residents' computer bulletin board system: results of a 23-month pilot study

The Residents' Computer Bulletin Board System (RBBS) originated as an offshoot of a research project designed at a 1988 meeting of Baltimore's chief medical residents. Beginning on March 1, 1989, RBBS offered electronic mail, bulletins, file transfers, newsletters, and data collections to physicians-in-training. It operated for 695 days before ResNet, sponsored by the American College of Physicians, superseded it. This report details how medical students, residents, and fellows used this electronic means of communication and offers some conclusions about the elements that future computerized bulletin board systems should have to succeed.