Surveyor v: lunar surface mechanical properties

The mechanical properties of the lunar soil at the Surveyor V landing site seem to be generally consistent with values determined for soils at the landing sites of Surveyor I and III. These three maria sites are hundreds of kilometers apart. However, the static bearing capability may be somewhat lower than that at the previous landing sites (2 x 10(5) to 6 x 10(5) dynes per square centimeter or 3 to 8 pounds per square inch). The results of the erosion experiment, the spacecraft landing effects, and other observations indicate that the soil has significant amounts of fine-grained material and a measurable cohesion.     

Suppression by actidione of development of rat liver L-tyrosine : 2-oxoglutarate aminotransferase activity

The development of L-tyrosine : 2-oxoglutarate aminotransferase in newborn rats is suppressed by actidione (cycloheximide), an inhibitor of protein biosynthesis, administered immediately after birth.     

Aneuploidy drives genomic instability in yeast

Aneuploidy decreases cellular fitness, yet it is also associated with cancer, a disease of enhanced proliferative capacity. To investigate one mechanism by which aneuploidy could contribute to tumorigenesis, we examined the effects of aneuploidy on genomic stability. We analyzed 13 budding yeast strains that carry extra copies of single chromosomes and found that all aneuploid strains exhibited one or more forms of genomic instability. Most strains displayed increased chromosome loss and mitotic recombination, as well as defective DNA damage repair. Aneuploid fission yeast strains also exhibited defects in mitotic recombination. Aneuploidy-induced genomic instability could facilitate the development of genetic alterations that drive malignant growth in cancer.     

Natural Selection for Miillerian Mimicry in Heliconius erato in Costa Rica

The natural color pattern of individuals of the unpalatable and mimetic butterfly Heliconius erato was altered to a unique nonmimetic pattern. When returned to natural populations, the nonmimetic individuals remained for shorter periods of time and received more wing damage indicative of predator attacks than did the controls. The results indicate that Müllerian mimicry was functioning to protect the butterflies from predation.