Microtubule function in immune and nonimmune lymphocyte-mediated cytotoxicity

Disaggregation of microtubular subunits in effector lymphocytes inhibits their ability to injure target cells. The inhibition is not reversed by denterium oxide, an agent known to stablize microtubular subunits.     

Long-range atmospheric transport of soil dust from Asia to the tropical north pacific: temporal variability

The concentration of airborne soil dust at Enewetak Atoll(11 degrees N, 162 degrees E) in April 1979 was 2.3 micrograms per cubic meter but decreased steadily to 0.02 microgram per cubic meter over the next 5 months. The spring dust is probably derived from China; its deposition rate ( approximately 0.3 millimeter per 1000 years) suggests that it may be a significant contributor to the deep-sea sediments of the North Pacific.     

Nickel-iron spherules from aouelioul glass

Nickel-iron spherules, ranging from less than 0.2 to 50 microns in diameter and containing 1.7 to 9.0 percent Ni by weight, occur in glass associated with the Aouelloul crater. They occur in discrete bands of siliceous glass enriched in dissolved iron. Their discovery is significant tangible evidence that both crater and glass originated from terrestrial impact.     

Volatile components of green walnut husks

Volatiles were isolated from whole green mature walnuts (Hartley variety) with husks still intact using dynamic headspace sweeping with trapping on Tenax. A total of 45 volatile compounds were identified by GC-MS. Major volatiles identified included (E)-4, 8-dimethyl-1,3,7-nonatriene, pinocarvone, pinocarveol, myrtenal, myrtenol, (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, caryophyllene epoxide, verbenol, verbenone, and terpinolene. Green walnuts that had been infested with codling moth showed appreciably higher amounts emitted for (E)-4,8-dimethyl-1,3,7-nonatriene, (E, E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, alpha- and beta-pinenes, sabinene, (E)-beta-ocimene, (E,E)-alpha-farnesene, and linalool. The infested nuts also emitted benzyl methyl ether, isobutyl cyanide, and 1-nitro-3-methylbutane, compounds not found with the healthy nuts. Volatiles from uninfested green walnuts at the maturity stage where the husk was just beginning to split were also analyzed and compared.     

Protein supplementation of ruminants consuming low-quality cool- or warm-season forage: differences in intake and digestibility

An in situ study (Exp. 1) using 4 ruminally cannulated steers (343 ± 11 kg of BW) in a completely randomized design was used to compare ruminal degradation characteristics of low-quality cool-season (C3; Kentucky bluegrass straw; Poa pratensis; 6.3% CP; DM basis) and warm-season (C4; tallgrass prairie; 5.7% CP; DM basis) forage. Four ruminally cannulated steers (252 ± 8 kg of BW; Exp. 2) and 4 wethers (38 ± 1 kg of BW; Exp. 3) were used in two 2 × 2 factorial arrangements of treatments to determine the influence of supplemental CP (CPSupp; soybean meal; 0.09 and 0.19% of BW, CP basis, for steers and lambs, respectively) on nutrient intake and digestion of C3 and C4 forages. Steers and wethers were allotted to separate 4 × 4 Latin squares that ran simultaneously with 20-d periods. In Exp. 1, C3 had a greater A fraction (fraction of total pool disappearing at a rate too rapid to measure) and effective degradability of DM and NDF compared with C4 (P < 0.01). In addition, C3 had a greater (P < 0.01) A fraction and effective degradability of N, whereas the C fraction (fraction of total pool unavailable in the rumen) was less (P < 0.01) than those for C4. Consequently, RDP accounted for 84.7% of total CP in C3 as compared with 66% for C4 (P < 0.01). In Exp. 2, a CPSupp × forage interaction (P < 0.01) was noted for forage and total DMI, with CPSupp increasing intake of C4 by 47% and intake of C3 forage by only 7%. Dry matter digestibility responded similarly, with a CPSupp × forage interaction (P = 0.05; CPSupp increased digestibility by 21% with C4 and by 9% with C3 forage). In addition, CPSupp × forage interactions were noted for ruminal liquid retention time (P = 0.02; CPSupp decreased retention by 3.6 h with C4 and by only 0.6 h with C3 forage) and particulate passage rate (P = 0.02; CPSupp increased passage by 46% with C4 and by 10% with C3 forage). As in Exp. 2, a CPSupp × forage interaction (P = 0.01; CPSupp increased digestibility by 18% with C4 and by 7% with C3 forage) was observed with DM digestibility in Exp. 3. In contrast, only N balance (P < 0.01) and N digestibility (P < 0.01) were affected by CPSupp. These data suggest that intake and digestion of low-quality C3 and C4 forages by ruminants are not similar and, more important, that the physiological response of ruminants to protein supplementation of low-quality forage is dependent on forage type.