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Santanu K Datta1,2, Adam H Buchanan3, Gail P Hollowell4, Henry F Beresford5, Paul K Marcom1,3, Martha B Adams1,61Department of Medicine, Duke University; 2Center for Health Services Research in Primary Care, Durham VA Medical Center; 3Duke Cancer Institute, Duke University; 4Department of Biology, North Carolina Central University; 5School of Nursing, Duke University; 6Department of Community and Family Medicine, Duke University, Durham, NC, USAAbstract: Cancer genetic counseling (CGC) provides benefits and is the standard of care for individuals at increased risk of having a hereditary cancer syndrome. CGC services are typically centered in urban medical centers, leading to limited access to counseling in rural communities. Telemedicine has the potential to improve access to CGC, increase efficient use of genetic counselors, and improve patient care in rural communities. For telemedicine CGC to gain wide acceptance and implementation it needs to be shown that individuals who receive telemedicine CGC have high satisfaction levels and that CGC is cost-effective; however little research has been conducted to measure the impact of telemedicine CGC. This paper describes the design and methodology of a randomized controlled trial comparing telemedicine with in-person CGC. Measurement of patient satisfaction and effectiveness outcomes are described, as is measurement of costs that are included in an economic analysis. Study design and methodologies used are presented as a contribution to future comparative effectiveness investigations in the telemedicine genetic counseling field.Keywords: cancer genetics, genetic counseling, rural health services, telemedicine, satisfaction, cost

Discrimination of stable carbon isotopes in leaves is physiologically linked to water-use efficiency. Twenty-eight contrasting rice (Oryza sativa L.) cultivars were grown in the Philippines as upland rice under continuous, mild water stress. In situ measurements of leaf level water-use efficiency (WUE), net photosynthesis, conductance, water potential and leaf rolling were reported previously. The present study used leaf samples from the same experiment to determine, by means of a mass spectrometer, the carbon isotope discrimination (-) and total C and N content. Among rice cultivars, - ranged from 19.8 to 21.5960, with japonica types having the lowest mean -, aus types, the greatest, and indica types, intermediate-the opposite pattern to that observed for WUE. Carbon isotope discrimination was negatively correlated with WUE across all cultivars (P < 0.001) and within japonica (P < 0 -01) and aus (P < 0.05) groups, but not among indica rices. No correlation was observed between - and any other measured variable. Varietal differences in - and WUE were not related to leaf N content or stomata1 conductance. High WUE was associated with high leaf C content (P < 0.01), with aus cultivars having the lowest mean WUE and C content among the genetic groups. We conclude that even under variable field conditions, analysis of foliar - is a potential tool to identify water-use efficient rice genotypes.

Twenty-eight rice (Oryza sativa L.) genotypes of different origin and habitat were grown in upland culture during the dry season in the Philippines. Irrigation was supplied by overhead sprinklers at a level which kept the crop under continuous mild water stress. Leaf net CO2 assimilation, conductivity, intercellular CO2 concentration, water potential and leaf rolling status were determined on the same leaf of all varieties between 0900 and 1200 hours during the vegetative growth stage.Leaf water potential ranged from -0.8 and -1.3 MPa, with japonica types showing the highest values, AUS types from Bangladesh, the lowest, and indica types intermediate. Leaf conductivity and leaf rolling did not differ significantly among these groups. Most cultivars showed a logarithmic relationship between net CO2 assimilation and conductivity. AUS cultivars had the lowest rates of leaf CO2assimilation, but no differences were observed between japonica and indica varieties. At a given intcercellular CO2concentration, net CO2 assimilation was lowest in AUS varieties, resulting in low water use efficiency, and possibly indicating a higher CO2 compensation point for AUS than for other rice types.