Construction of a genetic map for arabica coffee.

We have used AFLPs to construct a genetic linkage map on a pseudo-F(2) population of arabica coffee ( Coffea arabica L.) derived from a cross between the cultivars Mokka hybrid and Catimor. Sixty trees from this population were selected on the basis of plant height distribution to construct a linkage map. A total of 456 dominant markers and eight co-dominant markers were generated from 288 AFLP primer combinations. Of the total number of markers generated, 68% were from cv. Catimor, 30% from cv. Mokka hybrid, and 2% were co-dominant. This distribution suggests that the heterozygosity within the cv. Catimor sub-genomes was twice that within the cv. Mokka hybrid sub-genomes. Linkage groups were constructed using MAPMAKER version 3.0, resulting in 16 major linkage groups containing 4-21 markers, and 15 small linkage groups consisting of 2-3 linked markers each. The total length of the map was 1,802.8 cM, with an average distance of 10.2 cM between adjacent markers. This genetic map will serve as the framework for mapping QTL controlling source-sink traits in the same population.

Genetic diversity of Carica papaya as revealed by AFLP markers.

Genetic relationships among Carica papaya cultivars, breeding lines, unimproved germplasm, and related species were established using amplified fragment length polymorphism (AFLP) markers. Seventy-one papaya accessions and related species were analyzed with nine EcoRI-MseI primer combinations. A total of 186 informative AFLP markers was generated and analyzed. Cluster analysis suggested limited genetic variation in papaya, with an average genetic similarity among 63 papaya accessions of 0.880. Genetic diversity among cultivars derived from the same or similar gene pools was smaller, such as Hawaiian Solo hermaphrodite cultivars and Australian dioecious cultivars with genetic similarity at 0.921 and 0.912, respectively. The results indicated that self-pollinated hermaphrodite cultivars were as variable as open-pollinated dioecious cultivars. Genetic diversity between C. papaya and six other Carica species was also evaluated. Carica papaya shared the least genetic similarity with these species, with an average genetic similarity of 0.432; the average genetic similarity among the six other species was 0.729. The results from AFLP markers provided detailed estimates of the genetic variation within and among papaya cultivars, and supported the notion that C. papaya diverged from the rest of Carica species early in the evolution of this genus.

Correlation of tissue constituents with the acoustic properties of skin and wound.

The purpose of this study was to compare measurements of ultrasound properties of skin and wound tissue with measurements of material properties such as total collagen concentration, acetic acid soluble collagen concentration, water concentration, and morphologic properties. Using a scanning laser acoustic microscope (SLAM), both ultrasonic speed and attenuation coefficient values were obtained for control skin (2-3 cm from the wound), for skin immediately adjacent to wounds (within 0.3 mm), as well as for wound tissue itself. The attenuation coefficient and speed measurements were lowest for wound tissue followed by adjacent skin and then control skin. As the wounds healed there appeared to be an increase in both speed and attenuation coefficient although the wound age at which these increases started and the length of time for which they continued varied from one dog to the next. The precision of duplicate sample measurement of wave speed was +/- 1.7% for control skin, whereas that for attenuation coefficient it was +/- 16%. Both ultrasonic speed and attenuation coefficient were directly correlated with tissue collagen concentration and inversely correlated with tissue water concentration (p less than 0.001). Attenuation coefficient correlated best (r = 0.73) with acetic acid soluble collagen concentration which reflects the changes in collagen taking place during the repair process. These attenuation measurements made at 100 MHz using the SLAM were compared for control skin and wound samples with measurements made at 10-40 MHz using backscatter acoustic techniques (BAT). The tissue samples analyzed by each ultrasound technique were from adjacent locations on the animals.

Measurement uncertainty assessment of the scanning laser acoustic microscope and application to canine skin and wound.

Accuracy and precision were experimentally evaluated for the scanning laser acoustic microscope (SLAM) by measurements on homogeneous liquids of known ultrasonic properties. Using aqueous solutions of bovine serum albumin, the attenuation coefficient accuracy and precision are +/-12% and +/-15%, respectively. Using Dow Corning 710, a silicone oil, the speed accuracy and precision are +/-2.9% and +/-0.4%, respectively. Precision was assessed using duplicate samples of canine skin and wound tissue. The estimated precisions in the measurement of the attenuation coefficient and speed were +/-16% and +/-1.7%, respectively.

Sterol excretion and cholesterol absorption in diabetics and nondiabetics with and without hyperlipidemia.

Fecal neutral and acidic sterols and cholesterol absorption were measured in 12 normal control subjects, 40 diabetic subjects with and without hyperlipidemia, and 27 subjects with hyperlipidemia but without diabetes mellitus. All subjects were on a low-cholesterol diet (less than 300 mg cholesterol/day). Fecal excretion of neutral and acidic sterols was increased in patients with hypertriglyceridemia and was more marked in diabetic patients with hypertriglyceridemia. Cholesterol absorption was decreased in diabetic patients with hypertriglyceridemia. Otherwise, there were no significant differences in sterol excretion or cholesterol absorption in diabetic and nondiabetic subjects compared with control groups with similar lipid levels. The best predictors of fecal neutral- and acidic-sterol excretion and of estimated cholesterol synthesis were very low [corrected]-density lipoprotein triglycerides and high-density lipoprotein cholesterol. Correction of hyperlipidemia may be beneficial in decreasing cholesterol synthesis and, thereby, in decreasing the risk of atherogenesis.

Ratio of serum urea to serum creatinine in wild black bears.

In winter, the ratio of serum urea to serum creatinine is 10 or less in denning female and male bears. In midsummer it is 22 or more, similar to that of other mammals. However, in late summer and early fall, while food is available, the urea-to-creatinine ratio approaches or becomes 10 or less. The low value of this ratio appears to indicate the biochemical state of hibernation, and many bears are in this state weeks before they den.