Design of super-strong and thermally stable nanotwinned Al alloys via solute synergy.

Al alloys have widespread industrial applications. However, their mechanical strength is often much lower than steels. Here, we investigate the influence of solutes on achieving ultrahigh strength and thermal stability of nanotwinned Al alloys. In situ micropillar compression tests show the addition of a small amount of Ti can significantly increase the mechanical strength of Al-Ni alloys to 2 GPa. Deformation induced detwinning, Ni segregation and grain coarsening as discovered in binary Al-Ni alloys are mostly absent in the ternary Al-Ni-Ti alloys. Moreover, the ternary Al-Ni-Ti alloys have outstanding thermal stability. Density function theory calculations reveal the synergetic pinning effect of Ni-Ti solute pairs on incoherent twin boundaries. This study demonstrates that the proper selection of synergistic solute pairs is critical to improve the thermal stability and mechanical properties of nanotwinned Al alloys.

Percentage of glycosylated hemoglobin and serum concentration of glucose in the blood of Japanese macaques and in three exotic ruminant species.

Serum glucose concentrations and percentages of glycosylated hemoglobin (GHb) were determined in 16 Japanese macaques and in 19 exotic ruminants (4 markhor, 5 mouflon, 10 aoudad). Mean (+/- SD) serum glucose concentration and GHb percentage in the Japanese macaques were 73 +/- 21.8 mg/dl and 4.7 +/- 0.82%, respectively. Serum glucose concentration was considered within the normal range for this species. The mean GHb percentage was within the normal range for man, indicating that GHb may be a valid indicator of long-term mean serum glucose concentration in the Japanese macaque. Mean serum glucose concentrations in the markhor, mouflon, and aoudad were 110 +/- 23.2, 111.4 +/- 37.1, and 132.5 +/- 38.5 mg/dl, respectively, and were considered within the normal ranges for these species. Mean GHb percentages for each of the 3 ruminant species were 0.425, 1.04, and 0.74%, respectively, which may have been below the range of accuracy for the testing procedure used, probably due to low erythrocyte permeability to glucose rather than to a shortened erythrocyte lifespan.

Disease patterns in the Detroit Zoo: a study of the avian population from 1973 through 1983.

A retrospective study was conducted to evaluate disease patterns in birds at the Detroit Zoo from 1973 through 1983. Data were derived from the zoo's medical and animal census records; the mean (+/- SD) population of birds during the study period was 469 +/- 42. Overall annual morbidity rates were 12.5% to 21.5%, with spring months having the highest morbidity rates. Annual mortality rates were 3.1% to 15.2%; 23.9% of the deaths were caused by microbial agents (particularly Erysipelothrix rhusiopathiae, hemolytic Escherichia coli, Salmonella spp, Aeromonas spp and Proteus spp), 15.4% by trauma, and 42.5% by nondetermined causes. The mute swan (Cygnus olor), mallard duck (Anas platyrhynchos), common gallinule (Gallinula chloropus), common rhea (Rhea americana), and red-billed hornbill (Tockus erythrorhynchus) were the 5 species most frequently affected of the 1,032 deaths from 1973 through 1983. The most frequently isolated parasites were Microtetramere spp, coccidian species, Diplotriaena spp, and Trichomonia spp.

Disease patterns in the Detroit Zoo: a study of reptilian and amphibian populations from 1973 through 1983.

A retrospective study was conducted to determine disease patterns in reptilian and amphibian populations at the Detroit Zoo from 1973 through 1983. In the reptilian population (mean +/- SD = 285.2 +/- 28), overall annual mortality rates were 1% to 40%. Mortality rates were highest in the fall months (20%) and lowest in the winter months (6%). The most frequently affected reptiles were iguana (Iguana iguana), reticulated python (Python reticulatus), rattlesnakes (Crotalus spp), common boa (Constrictor constrictor), and lizards (various genera of suborder Lacertilia). Of the 1,300 reptilian deaths from 1973 through 1983, 36.6% were caused by microbial agents, 12% by parasites, 11.6% by trauma, and 9.3% by nutritional deficiencies. The main microbial organisms that caused death were Aeromonas spp, Salmonella spp, Pseudomonas spp, Proteus spp, and Edwardsiella spp. The main parasites that caused death were Entamoeba spp and lungworms. Among amphibians, frogs and toads were the most frequently affected, and starvation and trauma were the most frequent causes of death.

Disease patterns in the Detroit Zoo: a study of the mammalian population from 1973 through 1983.

A retrospective study was conducted to evaluate disease patterns in the mammals at the Detroit Zoo from 1973 through 1983. The reindeer (Rangifer tarandus), common eland (Taurotragus oryx), rednecked Wallaby (Protemnodon rufogrisea), sitatunga (Tragelaphus spekii), and kangaroo (Macropus spp)- were the most frequently affected mammalian species. Parasitic agents (80% of which were internal parasites) caused morbidity in 60.2% of the mammals evaluated (n = 2,475) and microbial agents caused morbidity in 20.8% of the animals. Strongyloides spp, Trichostrongylus spp, coccidian species, Diphyllobothrium spp, and Trichuris spp were the internal parasites most frequently found. Overall annual mortality rate was 14% to 34%, with microbiological agents causing the highest mortality (26.5%). Pasteurella spp, beta-hemolytic Streptococcus spp, pathogenic Escherichia coli, Corynebacterium spp, and Klebsiella pneumoniae were the most frequent microbial causes of death. Cause of mortality could not be determined in 21.5% of the animals evaluated. The percentage of animals successfully treated increased from 1973 through 1983. Generally, however, the percentage of successfully treated animals was low (21% to 39%).

Studies on the effects of histaminergic agents on seizure susceptibility in mice.

The influence of pharmacological modifications of the functional activity of the central histaminergic system was studied on the susceptibility of mice to pentylenetetrazol-induced minimal (clonic) and maximal (tonic) seizures. Enhancement in the functional activity of the system by central administration of histamine or 4-methylhistamine of peripheral L-histidine loading failed to modify the risk of seizures. By contrast, reduction in histaminergic function was found to alter seizure susceptibility. Brocresine, an inhibitor of histamine synthesis, decreased and increased the risk of pentylenetetrazol-induced minimal and maximal seizures, respectively. Many, but not all, classical anti-histamines (H1 antagonist) and metiamide (H2 antagonist) and metiamide (H2 antagonist) increased minimal seizure susceptibility after periheral and intraventricular administration, respectively.