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Flavopiridol (L86-8275, HMR1275) is a cyclin-dependent kinase (Cdk) inhibitor that is in clinical trials as a cancer treatment because of its antiproliferative properties. We found that the flavonoid potently inhibited transcription by RNA polymerase II in vitro by blocking the transition into productive elongation, a step controlled by P-TEFb. The ability of P-TEFb to phosphorylate the carboxyl-terminal domain of the large subunit of RNA polymerase II was inhibited by flavopiridol with a K(i) of 3 nm. Interestingly, the drug was not competitive with ATP. P-TEFb composed of Cdk9 and cyclin T1 is a required cellular cofactor for the human immunodeficiency virus (HIV-1) transactivator, Tat. Consistent with its ability to inhibit P-TEFb, flavopiridol blocked Tat transactivation of the viral promoter in vitro. Furthermore, flavopiridol blocked HIV-1 replication in both single-round and viral spread assays with an IC(50) of less than 10 nm.

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Ethical issues are receiving considerable attention in the scientific community just as in other areas of society. Scientists who have in the past been accorded a select position in society are no longer guaranteed that status just by virtue of their occupation. Science, and scientists, may not yet be subject to the same intense scrutiny as some other professions, but the trend is evident. Scientists do have special obligations due to the nature of their profession, yet incidences of indiscretion are documented. Expectations of scientists in specific areas such as consulting, animal rights, and advocacy are discussed, and some thoughts on the scientist as an administrator are presented. A short summary of actions being taken in the field of ethics is included.

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Two experiments were conducted using 21-day-old, commercial-strain broilers to determine the effect of various commercial pigmentation products on pigmentation and bird performance. Birds received finisher/withdrawal diets that included 8% corn gluten meal or either a 2.5 or 5.0% substitution of gluten meal with Liquid OroGlo5, Dry Oroglo10, or Cromophyl-oro. When birds were slaughtered at either 48 or 51 days of age there were no differences in the birds' breast skin hue (dominant wavelength) or brightness (luminosity). Data indicated similar levels of pigmentation among birds in all treatments. Color intensity (excitation purity) values of shank and breast skin samples suggested that the liquid form of OroGlo was more effective than the dry form in pigmenting broiler skin when both forms were fed at equal calculated levels. Data indicated that actual xanthophyll intake was higher when the liquid source was fed. Body weight gain and feed efficiency among the treatments, in general, indicated that commercial pigment sources can be substituted for corn gluten meal without appreciably altering broiler performance.

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Two trials were conducted with broiler chicks from hatch to 21 days of age to study the effects of feeding high moisture corn diets with and without a mold inhibitor. Monoprop High moisture corn (HMC) diets supported growth rates and dry matter feed conversion ratios as well as dry corn diets when Monoprop was present in the feed even when the feed was seeded with moldy corn screenings. Without the mold inhibitor, body weight gains were depressed. This was not due to depressed feed intake as feed consumption for chicks on HMC diets without mold inhibitor was as high as other groups.

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Three experiments were conducted with broiler chicks from 1 to 21 days of age to evaluate Florida 301 variety of wheat and Beagle 82 variety of triticale. In Experiment 1, a completely randomized design (CRD) was used for five dietary treatments: yellow corn-soy (control), triticale-soy, yellow corn-triticale-soy, wheat-soy and yellow corn-wheat-soy. Diets were balanced to maintain equal levels of sulfur amino acids and lysine and were kept isocaloric (3,124 kcal/kg) using corn oil. In Experiment 2, a CRD was used for 10 dietary treatments. Each grain was substituted partially and totally for corn on both iso and nonisocaloric basis. Animal fat was the supplemental fat source. In Experiment 3, a CRD was used for 8 dietary treatments. Each grain was substituted for corn isocalorically using corn oil, animal fat, or both as supplemental fat sources. Results from these experiments showed that Florida 301 wheat is an excellent cereal grain for broiler chicks as measured by feed efficiency and growth response, which was numerically but not significantly greater than with a corn-soy control diet. Growth response was inconsistent with Beagle 82 triticale throughout the three experiments. However, feed efficiency was better with triticale diets than corn-based diets.

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Use of nondestructive quality evaluation techniques for agricultural products is steadily increasing. Reasons for increased application and refinements of techniques in processing of agricultural products are discussed, especially with regard to more automation and less labor in processing, increased processing rates, and demand for more quality and uniformity of product. Information is presented on a number of nondestructive techniques presently being used, and the need for additional development is covered. Special emphasis is given to the efficiency, practicality, and economic feasibility of various techniques. Agricultural products covered include peanuts, pecans, poultry, eggs, pork, and seeds. Nondestructive techniques discussed that are used for processing these commodities into uniform, high-quality products include visual examination, weighing, screening, gravity sorting, air classification, electronic sorting, and estimation of chemical composition. A more detailed discussion of electronic color sorting of peanuts, pecans and almonds is presented, particularly in relation to aflatoxin sampling and reduction, preparing for further processing, and evaluation of commercial sorters for speed and accuracy.

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