IS THE PROFIT MOTIVE AN IMPORTANT DETERMINANT OF GRAZING LAND USE AND RANCHER MOTIVE?

We build our economic models and estimate grazing policy impacts based on the standard economic model of profit maximization. Yet, over 30 years of research and observation has shown that, for many, consumptive and quality of life values are the most important reasons for the purchase of western ranches. Ranch buyers want an investment they can touch, feel and enjoy, and they have historically been willing to accept low returns from the livestock operation. Profit maximization appears to be an inadequate model for explaining rancher behavior; in estimating what impacts altered public land policies will have; and in de-scribing grazing land use and value. In this study, only 27% of the value of New Mexico ranches in the most productive rangeland areas was explained by livestock production potential. Economists and policy-makers must take the influences of both traditional livestock production and quality of life values into ac-count when determining appropriate policies for western rangelands.Land Economics/Use, Livestock Production/Industries,

Differential localization of glutamate receptor subunits at the drosophila neuromuscular junction

The subunit composition of postsynaptic neurotransmitter receptors is a key determinant of synaptic physiology. Two glutamate receptor subunits, Drosophila glutamate receptor IIA (DGluRIIA) and DGluRIIB, are expressed at the Drosophila neuromuscular junction and are redundant for viability, yet differ in their physiological properties. We now identify a third glutamate receptor subunit at the Drosophila neuromuscular junction, DGluRIII, which is essential for viability. DGluRIII is required for the synaptic localization of DGluRIIA and DGluRIIB and for synaptic transmission. Either DGluRIIA or DGluRIIB, but not both, is required for the synaptic localization of DGluRIII. DGluRIIA and DGluRIIB compete with each other for access to DGluRIII and subsequent localization to the synapse. These results are consistent with a model of a multimeric receptor in which DGluRIII is an essential component. At single postsynaptic cells that receive innervation from multiple motoneurons, DGluRIII is abundant at all synapses. However, DGluRIIA and DGluRIIB are differentially localized at the postsynaptic density opposite distinct motoneurons. Hence, innervating motoneurons may regulate the subunit composition of their receptor fields within a shared postsynaptic cell. The capacity of presynaptic inputs to shape the subunit composition of postsynaptic receptors could be an important mechanism for synapse-specific regulation of synaptic function and plasticity

Asymmetries in Simple Feature Searches for Color

AbstractObservers were required to search for and find a target stimulus that differed from distractor stimuli only in chromaticity. Pairs of target and distractor colors were chosen so that in some conditions the two members of a pair differed in hue, in saturation, or in both hue and saturation. For each type of condition, a number of pairs of colors representing varying degrees of perceptual difference were chosen. Each member of each pair of colors served as both the target and distractor color while the other member of the pair served in the remaining role. The largest asymmetries in search times occurred when the target and distractors differed in saturation. Somewhat smaller asymmetries occurred with differences in both saturation and hue, and no asymmetries occurred with hue differences. Results suggest that the asymmetries are related to the time required to encode and transmit the chromatic information centrally rather than the properties of the search process itself. Copyright © 1996 Elsevier Science Ltd

THE LACK OF A PROFIT MOTIVE FOR RANCHING: IMPLICATIONS FOR POLICY ANALYSIS

The economic impact of changing land-use policies has traditionally been estimated using the standard economic model of profit maximization. Ranchers are assumed to maximize profit and to adjust production strategies so as to continue maximizing profit with altered policies. Yet, nearly 30 years of research and observation have shown that family, tradition, and the desirable way of life are the most important factors in the ranch purchase decision - not profit. Ranch buyers want an investment they can touch, feel, and enjoy, and they historically have been willing to accept relatively low returns from the livestock production. Profit maximization appears to be an inadequate model for explaining rancher behavior, describing grazing land use, and estimating the impacts of altered public land policies. In this paper, we investigate the relative importance of livestock production income and desirable lifestyle attributes in determining the market value of western ranches, and we explore what this means for economic models and policy analysis.Agricultural and Food Policy, Land Economics/Use,

Teacher Conceptions, Curriculum Ideologies, and Adaptations to Linear Change in River School District: Implications for Gifted and Talented

Curriculum ideologies are educational theories applied in everyday pedagogical practice. In this study, to better meet the learning needs of their students, four middle school teachers used a variety of ideologies as a professional toolbox. When confronted with school district standardization, these teachers adapted; however, as predicted by earlier studies, adjustments required the loss of previously successful curriculum. As predicted by Feldhusen, these losses affected teachers of high-level students (honors and gifted and talented) the most. In this district, two such teachers opposed standardization; nevertheless, even with resistance, they lost ideological-based curriculum choices. What are teachers of high-level students to do? Any standardization program will threaten and/or change eclectic ideological praxes. With such a dichotomy, a split is revealed between teacher beliefs and practices. In this study, an honors teacher could not bear the split and decided to stop teaching rather than give up her curricular eclecticism

Spectral Line Removal in the LIGO Data Analysis System (LDAS)

High power in narrow frequency bands, spectral lines, are a feature of an interferometric gravitational wave detector's output. Some lines are coherent between interferometers, in particular, the 2 km and 4 km LIGO Hanford instruments. This is of concern to data analysis techniques, such as the stochastic background search, that use correlations between instruments to detect gravitational radiation. Several techniques of `line removal' have been proposed. Where a line is attributable to a measurable environmental disturbance, a simple linear model may be fitted to predict, and subsequently subtract away, that line. This technique has been implemented (as the command oelslr) in the LIGO Data Analysis System (LDAS). We demonstrate its application to LIGO S1 data.Comment: 11 pages, 5 figures, to be published in CQG GWDAW02 proceeding

A dedicated haem lyase is required for the maturation of a novel bacterial cytochrome c with unconventional covalent haem binding

In bacterial c-type cytochromes, the haem cofactor is covalently attached via two cysteine residues organized in a haem c-binding motif. Here, a novel octa-haem c protein, MccA, is described that contains only seven conventional haem c-binding motifs (CXXCH), in addition to several single cysteine residues and a conserved CH signature. Mass spectrometric analysis of purified MccA from Wolinella succinogenes suggests that two of the single cysteine residues are actually part of an unprecedented CX15CH sequence involved in haem c binding. Spectroscopic characterization of MccA identified an unusual high-potential haem c with a red-shifted absorption maximum, not unlike that of certain eukaryotic cytochromes c that exceptionally bind haem via only one thioether bridge. A haem lyase gene was found to be specifically required for the maturation of MccA in W. succinogenes. Equivalent haem lyase-encoding genes belonging to either the bacterial cytochrome c biogenesis system I or II are present in the vicinity of every known mccA gene suggesting a dedicated cytochrome c maturation pathway. The results necessitate reconsideration of computer-based prediction of putative haem c-binding motifs in bacterial proteomes

Sn-modification of Pt7/alumina model catalysts: Suppression of carbon deposition and enhanced thermal stability.

An atomic layer deposition process is used to modify size-selected Pt7/alumina model catalysts by Sn addition, both before and after Pt7 cluster deposition. Surface science methods are used to probe the effects of Sn-modification on the electronic properties, reactivity, and morphology of the clusters. Sn addition, either before or after cluster deposition, is found to strongly affect the binding properties of a model alkene, ethylene, changing the number and type of binding sites, and suppressing decomposition leading to carbon deposition and poisoning of the catalyst. Density functional theory on a model system, Pt4Sn3/alumina, shows that the Sn and Pt atoms are mixed, forming alloy clusters with substantial electron transfer from Sn to Pt. The presence of Sn also makes all the thermally accessible structures closed shell, such that ethylene binds only by π-bonding to a single Pt atom. The Sn-modified catalysts are quite stable in repeated ethylene temperature programmed reaction experiments, suggesting that the presence of Sn also reduces the tendency of the sub-nano-clusters to undergo thermal sintering

Observations of neck-collared Canada geese near John F. Kennedy International Airport, New York

Canada geese (Branta canadensis) often cause significant damage when they strike aircraft. They are responsible for a reported minimum of $2.6 million in damage per year to civil aviation in the United States. Knowledge of goose movements in relation to airports would allow wildlife managers to allocate time and funds to manage those populations that pose the greatest threat to aircraft. We placed alpha-numeric neck collars on 300 Canada geese within 8 km of both John F. Kennedy International Airport (JFKIA) and LaGuardia Airport in New York, New York. We conducted weekly observations for 2 years within a 12- km radius of JFKIA at locations used by the geese. At the conclusion of the study, 45% of the collared geese remained within an 8-km radius of JFKIA, and four were killed at JFKIA during wildlife control operations. We observed birds at their original banding sites 75% of the time, and within 5 km of the banding location 95% of the time. Geese that remained in the study area were re-sighted at a mean straight-line distance of 3.6 (±3.1) km from their original banding location. We note that 78% of the re-sighting locations used by geese were within 8 km of JFKIA and that movements of these geese could take them over or onto JFKIA. Oiling goose eggs to kill the embryos, rounding up of flightless birds within 8 km of the airport, and bird-control activities at JFKIA and nearby areas all should be continued to reduce the probability of a catastrophic bird strike between aircraft using JFKIA and local Canada geese