DNase concentration assay to obtain DNA-free RNA from sugarcane leaves.

The success of gene expression studies, protein synthesis, and construction of cDNA libraries directly depends on the purity and integrity of the RNA used in these tests, as even minor amounts of contaminant DNA (<1%) can produce a false positive amplification signal in quantitative real-time PCR. For RNA contaminated with genomic DNA, an essential step in the studies on gene expression is the treatment of the RNA samples with DNase. This study was conducted to test three different concentrations of DNase I (0.02, 0.04, and 0.06 µL/​​ng of RNA), which were chosen based on the results of the RNA sample quantifications and as indicated by the manufacturer, to digest genomic DNA present in the RNA samples extracted from sugarcane leaves with the Concert™ Plant RNA Reagent. The results showed that all three concentrations of DNase significantly reduced DNA concentrations. However, RNA was also degraded on DNase I treatment. In addition, the amount of DNA present in the RNA samples after purification with DNase I was sufficient for its amplification in the tests conducted with conventional PCR. Furthermore, the condition of RNA samples obtained after the treatments allowed for real-time PCR. Therefore, we concluded that 0.02 µL DNase I was the ideal concentration for sugarcane RNA purification, as higher concentrations do not increase the efficiency of the genomic DNA digestion in RNA samples and only make the purification process more expensive. This study provides important information on the effect of high concentrations of DNase I and complements previous studies that have so far tested only the DNase concentration recommended by the manufacturer.

Molecular characterization of accessions of Cratylia argentea (Camaratuba) using ISSR markers.

Cratylia argentea (Desv.) Kuntze (Fabaceae) is a drought-tolerant, perennial legume found primarily in Brazil, Bolivia, and Peru. The shrub is well adapted to acid soils and exhibits high productivity and nutritional value, characteristics that would favor its use as a dry season animal forage supplement in semiarid regions. In plant improvement programs, the production of elite hybrids with superior traits is generally achieved by crossing parents that exhibit the highest level of genetic divergence. Therefore, the aim of the present study was to assess genetic diversity among 13 accessions of C. argentea from the same population maintained in the active germplasm bank of Embrapa Meio-Norte using inter-simple sequence repeat (ISSR) markers. Genetic similarities between C. argentea accessions were estimated from Jaccard coefficients, and a dendrogram was constructed using the unweighted pair group method with arithmetic average (UPGMA). The set of 15 primers selected for ISSR analysis generated a total of 313 loci of which 79.23% were polymorphic. The mean number of bands per primer was 20.87, and the amplicons ranged from 280 to 3000 bp in size. Primers UBC834 and UBC827 generated the largest number of polymorphic loci and exhibited 90.91 and 100% polymorphism, respectively. The coefficients of genetic similarity among accessions varied between 0.49 and 0.73. UPGMA cluster analysis allowed the identification of four genotypic groups and demonstrated the existence of considerable variability within the collection. Potential progenitors were selected that would offer good possibilities of obtaining unusual and favorable combinations of genes in a plant breeding program.

Military participation in emergency humanitarian assistance.

Military forces of the United States and other countries possess training, equipment and capabilities that are suited for work in disaster preparedness and assistance. Information on the use of military units in domestic and foreign disaster-related efforts, particularly by United States forces in the medical area, was obtained by review of the literature and unpublished military reports, and from interviews with people who have been involved with disaster-related activities. The historical reasons for viewing United States forces as resources in disaster situations are identified. Additionally, issues and problems related to disaster preparedness and assistance in general, and more specifically, to the past and future use of military personnel for this mission are examined. The need for a defined military mission for emergency humanitarian assistance and the need for a military organizational structure to support this mission are identified. Once these two critical issues have been properly addressed, the United States military should participate in the establishment of a disaster institute for joint civilian-military disaster planning and training, in both domestic and foreign areas.

The role of military medicine in military civic action.

We are moving into an era when U.S. military forces will be called upon frequently to perform military civic action (MCA) projects. Such projects, have been used successfully and unsuccessfully, primarily in the areas of medicine and engineering, to enhance the standing of military forces with indigenous populations. However, the available criteria for planning and assessing MCA projects are not widely known. These related and overlapping criteria are supported by facts, interpretative data, anecdotes, and common sense, but none can be considered absolute. Selected criteria are defined, reviewed, and illustrated with examples of past successes and failures.

Donor and nondonor motivations.

In an attempt to gain insight into the motivations of blood donors and nondonors, two paper and pencil questionnaires were developed and mailed to approximately 7,000 individuals. In response, 1,429 nondonors and 200 donors completed and returned usable questionnaires. Among donors, awareness of the need for blood, altruism, and investment for the future (blood credit) were the chief motivating factors. Among nondonors the major deterrent was belief in medical disqualification. Of the 33 per cent who claimed medical disqualification, 40 per cent gave clearly invalid or questionable reasons. Fear, while a substantial factor among nondonors, was not as great a deterrent to blood donation as had been previously thought. A dimension focusing upon failure to confront the issue of donating was derived and found to equal or exceed fear in importance. The influence of such items as sex, age, number of donations, and number of children on reasons expressed was examined. The major results were compared with the findings of previous studies. An approach-avoidance model of blood donation was outlined, and implications for donor recruitment are discussed.