No description available.

Tissues (liver, spleen, pancreas, and aorta) and hair taken at autopsy from diabetic and non-diabetic southwestern Indians (mainly Pima) were analyzed for chromium (Cr) using flameless atomic absorption spectrophotometry. The Cr levels in both tissues and hair from diabetic subjects were consistently lower than in those from non-diabetic individuals. There were so few individuals in each group that it was not possible to accurately correlate a given tissue either with any other tissues or hair.

No description available.

No description available.

No description available.

No description available.

Phenology of tetraploid Larrea tridentata was studied at four sites, one east and three west of Tucson, Pima County, Arizona in 1972-1974 and 1981. Leaf initiation, stem elongation, flower buds, flowers, maturing fruits and mature fruits were recorded at regular intervals on a sample of 10 tagged plants at each site. Quantitative production of maturing fruits on each sampled plant was estimated during the 1981 spring and summer seasons. The time required for individual new flowers to develop into mature fruits was determined for 1981. These phenological data were related to precipitation and temperature during 1972-1974 and 1981. Leaf initiation and stem elongation were continuously active on at least some parts of all sampled plants throughout the study, indicating year-round vegetative growth of Larrea in this part of the Sonoran Desert. One or more of the four reproductive phenophases were present throughout the 1972-1974 and 1981 periods. Flower buds were initiated during any time of the year. Spring flowering was the most dependable, summer flowering was frequent but less consistent and fall and winter flowerings were occasional, irregular and far more variable. Spring flowering persisted longer than summer flowering. Maturing fruit production was much greater in the spring than in the summer. Approximately 53 to 65 days were required in the spring and 42 to 47 days in the summer for new flowers to develop into mature fruits. Active vegetative growth invariably preceded the renewal of any reproductive activity. The emergence of flower buds appears to be triggered and sustained by the availability of sufficient soil moisture with minimal influence by temperature. However, higher temperatures tend to speed up the development of flower buds and flowers and fruit maturation. Differences in phenological responses among the four study sites appear to be caused mainly by local fluctuations in precipitation. The year-round vegetative growth activity and the frequent recurrence of reproductive activities observed in this study represent adaptive responses of Larrea to the biseasonal regime and the moderate winter temperatures characteristic of the northeastern portion of the Sonoran Desert.

Nocturnal rodents were censused every two weeks from January 1975 until September 1976 on two 1.69 ha (4.13 ac) live-trap grids. Grids were located about 48 kilometers (30 miles) south of Tucson AZ in a cresosote bush-cactus-mesquite-grassland ecotone. All nocturnal rodents, except Dipodomys merriami, were removed from one of the grids beginning in May 1975 and continuing biweekly until September 1976. Effects on the population biology of D. merriami were subsequently analyzed. Density, home range, weight changes, production of young, sex ratio and minimum residence (time between first and last capture) of D. merriami were analyzed on each grid. Effects of removal on D. merriami were minimal. Density on the removal grid increased immediately after removal began; however, this effect decreased with time, as numbers of d. merriami decreased on both grids. Total heteromyid density on the control grid also decreased during the experiment. Removal caused no significant effect on home range. A similar, consistently inverse relationship between home range and density occurred on both grids. Mean weight for both reproductively active and inactive males and females was not significantly different following removal. The number of juveniles increased slightly after removal began, but production of young on both grids was similar, and low. The two populations exhibited different sex ratios for four months after removal began, with males being caught more frequently on the removal grid. Minimum residence times were similar on both grids. It appears that the relatively increased availability of reources had only a temporary effect on D. merriami. In the longer perspective, D. merriami seems to have exhibited what is probably an evolved response to increased resources; i.e., long-term changes in population parameters occur slowly, and only when improved conditions persist for relatively long periods of time.

Golden Gate Mountain appears as a spur projecting westward from the Tucson Mountain range. It is made up of the capping Cat Mountain Rhyolite, the slope - forming Amole Formation, and a variety of intrusions of differing compositions. The emplacement of the andesitic portion of the intrusions occurred during, and probably lasted long after, the deposition of Amole Formation. The hot magma fluidized the wet sediments. Part of the fluidized materials formed pipes and dikes of tuffisites and part was brought up into the basin and contributed to the sedimentation of Amole Formation. During upper Amole time the intrusion of andesite increased in intensity. Part of the basin rapidly subsided and thick deltaic sediments and graywacke were formed. The development of a hinge line accompanied this subsidence. The hinge line controlled the occurrence of fluidization which undercut the Amole beds. The beds slumped into the fluidized parts. The process culminated in forming a large orifice through which the Cat Mountain Rhyolite welled up. The orifice is reflected in the sedimentary beds by the development of a funnel- shaped structure in the central part of which the capping of Cat Mountain Rhyolite is located. The bordering brecciated Amole beds represent the associated slump effects.

The Atlas Mine is located on the northwest flank of the Silver Bell mountains; Silver Bell mining district, Pima County, Arizona. The deposit is high grade (?) sine-copper mineralization in an altered sedimentary sequence. Rocks in the area include Precambrian (?) alaskite; Permian (?) limestone, quartzite and siltstone; Tertiary (?) monzonite, quartz monzonite, quarts latite porphyry and dacite porphyry; and Quaternary alluvium. The limestone has been largely metamorphosed to a mass of tactite, siltstone has been locally metamorphosed to hornfels, and the quartzite has been silicified, locally shattered and altered. Mineralization is related to NE and E-W trending fault systems, and similarly trending intrusive dikes. Predominate ore minerals are sphalerite and chalcopyrite, associated with pyrite, specular hematite and “high temperature" silicates. Copper mineralization is related to the silicified sediments. Zinc mineralization is present in silicates but is more predominate in areas of recrystallized calcite and extensive garnetization, suggesting incomplete replacement of the original sediments by the silicates. Further exploration and development should be undertaken in areas of favorable structural control, and adjacent to favored intrusives.