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1. Several aspects of the behavioral ecology of feral horses (Equus caballus) were studied in Grand Canyon, Arizona, USA. Most bands contained three to five horses that included one stallion and his harem. Males that did not obtain a harem remained solitary. Throughout the study bands remained stable in composition. 2. Home ranges for all bands decreased in size in successive warm months, probably due to increased ambient temperature and drought. This resulted in greater utilization of spring areas that led to increased interband confrontation and agonistic display. 3. Territoriality was not observed in individual horses or bands, but bands hierarchial in both inter- and intraband structures. Interband stallion dominance was reinforced through posturing and fighting. Intraband hierarchies, as determined by dominance coefficients, were independent of individual size in three of four bands. 4. Indexes of nervousness (NER), calculated while horses were drinking, showed that stallions were less nervous than mares. A low NER was correlated with individuals leading toward drinking areas, whereas a high NER existed in individuals initiating flight although no single horse acted consistently as a leader. 5. Diurnal activity patterns were correlated with ambient temperatures. [ABSTRACT FROM AUTHOR]

The article presents a study which investigated the occurrence of dichloro-diphenyl-dichloroethylene (DDE) in dairy feeds found in milk shed in Arizona. The study monitored major feed commodities in six dairies in the Salt River Valley, Arizona from 1979-1985. It says that the source of DDE during the period was probably the acaracide dicofol.

Confusion about the role of residential satisfaction vis-à-vis structural factors in the mobility process stems from the failure to examine the determinants of mobility over varying time frames and housing tenures. Using survey data for a random sample of 580 Phoenix-area households, we test models of short-term (1 year) and long-term (5 years) mobility expectations for home owners and renters. The results show that residential satisfaction mediates the effects of structural variables on mobility expectations in the short term for home owners. In the long-term model for home owners and the short-term model for renters, the role of satisfaction as an intervening force declines in relative importance. Among renters, structural variables operate directly on long-term mobility expectations. [ABSTRACT FROM AUTHOR]

The article focuses on the educational objectives and goals of Michael Crow, president of Arizona State University in Phoenix, Arizona. Grow took the reigns of the university and gave it direction and energy beyond anyone could have imagined. He wanted to build a new American university for the twenty-first century. The key to his vision is to break away from the department-based model of most universities and build up excellence at problem-focused, interdisciplinary research centers.

Reports on the lawsuit filed by the Arizonian tribe, the Havasupai, against the geneticists researching the genetic cause of the high incidences of type 2 diabetes within the tribe. Worth of the lawsuit; Reasons behind the tribe's decision to file the lawsuit; Alleged reason behind the problem that spawned the legal action.

Once landfills are closed and maintained according to the US Environmental Protection Agency's standards and regulations, they are potential sites for revitalization efforts, particularly via agricultural activities. This project was commissioned by the City of Tucson Environmental Services Department as part of an effort to explore ways to reuse one or more of the 16 landfills the department manages in the Tucson metropolitan area. The objective of this project was to assess the feasibility of using a closed landfill to support safe goat browsing. A site history and investigation was conducted at the Harrison Landfill in Tucson, Arizona, to characterize the soil quality and uptake of deleterious metals by the following plants observed at the landfill: Pennisetum ciliare (buffel grass), Baccharis sarothroides (desert broom), Salsola tragus L. (Russian thistle), Larrea tridentata (creosote), Tamarix ramosissima (salt cedar), and Atriplex canescens (fourwing saltbush). Site characterization data were combined with known goat browsing and plant consumption patterns to determine exposure risks. It was observed that soil concentrations of metals (Al, Ag, As, Be, Ba, Fe, Co, Cu, Cr, Cd, Fe, Mn, Ni, V, Se, Mo, Sn, Sb, Pb) did not exceed Arizona Department of Environmental Quality's soil remediation levels. Tamarix ramosissima, Baccharis salicifolia (willow baccharis), Pennisetum ciliare, Salsola tragus L., Baccharis sarothroides, Larrea tridentata, and Atriplex canescens contained metal concentrations that fell well within maximum tolerable levels. In general, this project determined that after soil and plant assessment, urban, arid landfills may be used effectively for economic development through agricultural grazing ventures. [ABSTRACT FROM AUTHOR]

Round Butte is a small but complex Miocene diatreme that crops out ~ 190 m below the pre-eruptive surface, in the southeastern part of the Hopi Buttes volcanic field. Erosional remnants consist of a diatreme 170–190 m in diameter, of which the central 130–150 m is well-exposed in a massif featuring 20–30-m-high sub-vertical cliffs, and a 50-cm-thick basanite dike. Field mapping allowed us to define three main groups of pyroclastic rocks in the diatreme: undisturbed beds, disturbed beds, and non-bedded rocks. Pyroclastic rocks range in grain size from coarse tuff to tuff breccia and in componentry from juvenile-rich to lithic-rich, with a dominance of heterolithic lapilli tuffs. Rocks from the undisturbed bedded pyroclastic group are present above an unconformity found all around the massif, whereas the disturbed bedded and the non-bedded pyroclastic groups are always found below it. This unconformity was previously understood as the contact between the upper and the lower diatremes. The undisturbed beds above the unconformity indeed compose the upper diatreme, but the assemblage of non-bedded rocks (invasive columns) and disturbed beds (residual columns) below it is not typical of the lower diatreme. Instead, they represent a transition zone between the upper and lower diatremes. Such a transition zone also occurs in other diatremes, it is important genetically, and we propose to add it to the general model of maar-diatreme volcanoes. [ABSTRACT FROM AUTHOR]

The article discusses the highlights of the Winter Conference on Plasma Spectrochemistry which was held in Tucson, Arizona, on January 8 to 14, 2012. The event was attended by more than 500 researchers, manufacturers and users from more than 30 different countries. The poster and oral sessions focused on various topics like nanomaterials, laser and imaging techniques and new instrumentation and miniaturization.

The article discusses the author's experience as one of the founder of WYKO Corp. in Arizona. He said that WYKO was established in 1982 with the goal of providing a variety of metrology services. The company was developed with the help of his students at the Optical Sciences Center at the University of Arizona in Tucson. Various challenges he encountered in managing the company since 1982 are offered.

The article reports on the discovery of an ice-cemented soil and slabs of pure ice below the surface of the polar regions of Mars by the Phoenix, Arizona team of the National Aeronautics & Space Administration (NASA). It notes that the team found some cracking of the thermal contractions into polygons due to seasonal frost cycles. Moreover, researcher Joseph Levy and colleagues from the Portland State University conclude that the cracking is attributed to the sublimation of the deeper slab ice.

The article presents a study conducted by engineers at the University of Arizona in Tucson led by Marek Romanowski, which involves the development of an approach to make metal nanoparticles that human kidneys should be able to eliminate. The researchers have considered using liposomes as templates for the preparation of hollow, gold spheres 63 nanometers in diameter that can scatter light of preselected wavelengths. It is determined that optical resonances of gold and lipid differ from pure gold structures of the same size.

A letter to the editor is presented in response to the article "The Arizona Experiment," published in the previous issue.

We present observations on the frequency of large branchiopod associations found in north-central Mexico, and in Arizona, USA. Of a totalof 25 species involved in these assemblages, 12 were common in both areas. Fifty eight (43.3%) of the ponds in Mexico, and seventy-eight (47%) of those in Arizona had two or more species present. The combinations of species which occurred with highest frequency were Streptocephalus mackini with Thamnocephalus platyurus for Arizona, and T. platyurus, Triops sp., and Leptestheria compleximanus for Mexico. In Mexico, and Arizona, as in many parts of the world, multispecies assemblages of large branchiopods are a common phenomenon. Therefore, the 'Common rule' of 'one-phyllopod-per-habitat' advanced by Weise (1964) is inconsistent with field observations. Furthermore, since cases of co-occurrence of two or more congeneric species of Anostraca and Notostraca are not uncommon, generalizations about congeners not coexisting remain applicable only for the Spinicaudata. and Laevicaudata. On the basis of the literature, and of observations in the field and in the laboratory, we list potential factors contributing to the co-occurrence of several species within a pond. [ABSTRACT FROM AUTHOR]