The purpose of this study was to determine if the complexity and surface area of a macrophyte’s structure has an influence on invertebrate colonization, and to determine the influence of two non-native species on invertebrate colonization. Three plant architectures were compared. Floating leaved plants were represented by the following species: Nuphar lutea, Nymphaea odorata, and Brasenia schreberi. Moderately dissected leaved plants were represented by Potamogeton natans, and highly dissected leaved plants were represented by two non-native species, Myriophyllum spicatum and Myriophyllum heterophyllum. The number of invertebrates/g dry biomass and the number of individuals/m², diversity, evenness, and richness were calculated for comparison. The density of invertebrates was significantly different among the different plant architecture types for both individuals per m² and individuals per/g dry biomass (ANOVA, F=33.53, p < 0.0001; ANOVA, F=194.41, p < 0.0001). The highly dissected milfoils had the greatest density of individuals per gram dry plant biomass compared to the moderately dissected plants, and the moderately dissected plants had a greater density of individuals per gram dry mass than floating leaved plant. There were also differences in terms of invertebrate community diversity (H'), (ANOVA, F=l7.08, p < 0.001), and richness (ANOVA, F= 35.52, p < 0.001), but not evenness (ANOVA, F = 1.83, p = .0961). When the number of invertebrates/g dry plant biomass was examined in lakes where the highly dissected plants were ”rare/not observed", there was a lower density of invertebrates per gram dry biomass. This was significantly lower than in lakes where the highly dissected plants were both ”common” and ”dominant” (ANOVA, F=3.31, p = 0.0393). Data analysis was strongly affected by the density of the oligochaete Sty/aria and the amphipod Hyallela azteca, as evident in the Principle Component Analysis. Parameters associated with the two axes, principle component 1 and principle component 2, explained 86% of the variation in epiphytic invertebrate density.

This study investigated relationships between blue grouse (Dendragapus obscurus) winter habitat and blue grouse adaptive strategies and overwinter survival. Blue grouse metabolism, physical characteristics of use-trees and roost sites , microclimatic parameters at roost sites, daily winter energy costs, and specific energy-saving behaviors were studied. Blue grouse have a relatively low standard metabolic rate (SMR; 0.835 ml o2 · g-1 · hr-1) and lower critical temperature in comparison to other northern tetraonids . Metabolic rate did not significantly increase from -5 to -20 C. Ambient temperature (Tal and the square root of wind speed were significantly correlated with metabolic rate. Blue grouse selectively roosted in the largest Douglas-firs (Pseudotsuga menziesii) and subalpine firs (~ lasiocaroa) during the day and night, respectively. All roost sites were typically adjacent to tree trunks in the lower 2/3 of trees . Nocturnal roosts provided greater canopy coverage and were located in continuous stands more often than diurnal roosts . Wind speeds were reduced by 63 and 85% at diurnal and nocturnal roosts, respectively. Douglas-firs provided exposure to solar radiation , protection from wind, and a food source during the day. Subalpine firs increased protection from the wind and provided near maximum canopy coverage at night. Nocturnal subalpine roost sites provided a 10% net energy savings in comparison to diurnal Douglas-fir roost sites. The average T a at the study area was with in the thermoneutral zone of blue grouse. The average field metabolic rate (FMR) of blue grouse measured with doubly-labeled water was about 1.4 times SMA, and was not influenced by weather. The proportion of FMR due to basal metabolism was twice that commonly assumed for other species, indicating the importance of microhabitat selection and relative inactivity by blue grouse in minimizing energy costs . Other energy saving behaviors included sunning , snow roosting, and walking uphill instead of flying. FMR measures (657 kJ·d-1) were within 12% of the energy costs estimated from average microclimatic values, and within 5% of the energy assimilation by captive blue grouse. Habitat selection by blue grouse, particularly microhabitat selection of roost sites , reflects active choices designed to minimize energy costs imposed by winter weather. This selection indicates the importance of Douglas-fir and subalpine fir for overwinter survival.

Measurements of energy expenditures for domestic animals are used as a basis to determine the total energy requirements for maintenance and for production. Most studies on energy metabolism have been conducted under controlled, confinement conditions, and the results extrapolated to free - ranging animals. Such approaches do not always represent the real energy costs of free existence in the range or pasture environment. This study compared energy expenditures of sheep and goats under free-grazing conditions and assessed the accuracy of the carbon dioxide entry rate technique (CERT) as compared to the oxygen consumption method. In addition, 24-hour activity budgets were used to construct energy budgets for both animal species. These estimates were compared to CERT measurements. Dietary organic matter, crude protein, gross energy, digestible protein, and digestible energy intakes, as well as the apparent digestibility coefficients for crude protein and gross energy were compared for both species in one of the grazing trials. The validation of CERT yielded the linear regression equation: Y = 0.878 + 5.333 ER where Y energy expenditure in Kcal·min-1, and ER is the C02 entry rate in grams of C02 carbon·min-1. The coefficient of determination (r2) was 0.979, and the residual standard deviation of ± 0.12 Kcal·min-1. Daily energy expenditure of goats was higher (P<.OS) than that of sheep in all grazing experiments. The overall means were 127.1 and 88.4 Kcal·Bw-.75.d-1 for goats and sheep, respectively. High ambient temperatures during one of the grazing trials apparently caused heat stress to the grazing animals. Both species responded to this situation by using behavioral adaptations and avoidance mechanisms. The energy budget method over-estimated energy expenditures of sheep by 9 percent, and grossly underestimated the energy expenditures of goats by 39 percent. The nutritive value of the diets selected by both species was similar . However, goats had higher (P< .OS) organic matter, crude protein, gross energy, digestible protein and digestible energy intakes. The apparent crude protein digestibility coefficient for goats was 20 percent higher (P<.OS) than that for sheep. On the other hand, gross energy digestibility coefficients were similar for both species. Goats appeared to have an edge in meeting their dietary protein requirements under free- ranging conditions. CERT can predict energy expenditures within ± 8 percent of the mean. It is a feasible technique for assessing energy expenditures of small ruminants under range conditions. The energy budget method was not reliable for estimating energy costs in small ruminants, especially goats.

Standard radio telemetry techniques via triangulation were used to determine coyote locations and to construct maps of coyote movement patterns in Curlew Valley (Utah and Idaho). Home range sizes were determined by establishing corresponding boundaries drawn on the basis of location, density and relative number of visitations (contour method), and then tracing the boundaries with a compensating polar planimeter. Mean home range sizes were determined directly for only those animals with home range values that reached an asymptote when plotted against corresponding time periods. This asymptotic value was considered the best estimate of the actual home range size. Four adult females and one adult male were in this category, with mean values of 18.3 km2 and 14.5 km2 respectively . The asymptote was estimated for home ranges which did not stabilize (mean values of 20.2 and 17.8 km for adult females and males respectively) using a home range estimator; validation of the estimator is discussed. Since no juvenile animal 's home range appeared to reach an asymptote, no asymptotic estimates were made . Various methods of constructing home range boundaries, their advantages and disadvantages, are listed. Standardization in the home range concept is necessary if meaningful comparisons are to be made between studies. Home ranges are dynamic, and must be considered in terms of specific time frames. Guidelines for adequate description of the home range are discussed with emphasis on quantity of data, time requirements and recognition of seasonal shifts in the home range. Map analysis suggested three general patterns with regard to home ranges; namely, animals with contiguous home range areas, those with disjunct home ranges, and wandering individuals. Fifty percent of the coyotes were trapped more than 0.5 km outside home range boundaries while an additional 42 percent were trapped on the periphery of the home range. Only 8 percent, all juveniles, were trapped within their home range. None of the 21 animals killed by hunters or trappers died well within their respective home ranges. Twenty-nine percent were killed on the periphery of their home ranges and 71 percent were killed an average of 11 km outside their home range ~n··~rl~Ties. Several movement patterns other than home range were discernible, including brief excursions away from the home range (sallies), dispersals, and total area utilized. Mean dispersal distances for adul t males, juvenile males and females respectively were 56, 9 and 54 km; no adult female was known to disperse. Juvenile females had the greatest tendency to disperse with 53 percent involved; juvenile males, 33 percent and adult males, 30 percent. Sallies were analyzed according to distance, duration and frequency, with adult females having the longest (4.9 km) and the greatest number of sallies (7.9 per month), and adult males spending the most time per sally (16.2 hours) as well as time per month (72.9 hours) in sally activity. The total area utilized by coyotes is discussed in terms of size and measurement. Mean values for total areas utilized are 138 km2 for adult females, 90 km 2 for adult males, 68 km2 for juvenile males and 46 km 2 for juvenile females. Home range configuration is discussed in terms of importance and variability in form, with the majority of shapes being ameboid in character. Linearity may be a function of the method used to establish home range boundaries and use of baseline data from fixed radio telemetry stations.

In May 1965, the first investigation and research in the native desert bighorn sheep in Utah was undertaken. The study was centered in the White Canyon area, San Juan County, in southeastern Utah. Seven other areas along the Colorado River were found to have smaller reminant populations of desert bighorns. The White Canyon population was determined to be between 124 and 144 desert bighorns (Ovis canadensis nelsoni), excluding lambs. The desert bighorns in southeastern Utah return from surrounding range lands each year to the same areas, known as lambing grounds, to give birth to their lambs. Ewes under one year of age were not known to breed. Rams over one year of age, although believed physiologically capable of breeding, were not observed doing so. The longevity of the bighorns was estimated at approximately 13 years. A relatively static population probably exists with a 50-5- ram-ewe ratio in the White Canyon area. Pneumonia, predators and lack of free water were believed to be responsible for the high lamb mortality found in the desert bighorn population. The lack of some nutrient in the diet is thought to be the reason for the high lamb susceptibility to pneumonia. Predators and the lack of the free water were believed to be major factors in lamb survival. The lack of available free water was found to be the greatest limiting factor to the bighorn population. Competition for forage and water by cattle and deer was found to be a major factor limiting bighorn populations. Internal parasites were found in numbers great enough to be detrimental to the sheep. All plant communities occupied by the sheep were found to be climax communities. On the south side of White Canyon the vegetation was in excellent condition and was in poor condition on the north side. Bighorns graze slightly more than they browse. Recommendations for the management of the desert bighorn sheep in southeastern Utah include continued studies, water developments, hunting rams over seven years of age, predator control and livestock reductions.

The tenacity with which water is held in the soil is an important factor in determining the availability of water to plants. It is this attraction for water by the soil particle which is the basic phenomenon of soil moisture tension. Soil moisture tension may be defined as the pressure difference that must be maintained across the wall of a porous cup in order to attain a zero transfer rate between water in the soil, which is subject to surface-force action, and water in the cup, which is not subject to surface force action.

Aminoglycoside-3′-Phosphotransferase IIIa is a widespread, promiscuous member of the phosphotransferase family of aminoglycoside modifying enzymes. This study provides results of combined calorimetry/NMR experiments to characterize and dissect the global thermodynamic properties of aminoglycoside–APH(3′)-IIIa complexes. Aminoglycoside binding to APH(3′)-IIIa is enthalpically driven with strong entropic penalty. 2′- and 6′-amino groups have significant contributions to the observed binding parameters. Formation of APH(3′)-IIIa complexes with substrate aminoglycosides shows a complex dependence on pH and is linked to protonation and deprotonation of both ligand and enzyme groups. We report pKa upshifts of ~1 unit for N2′ and N2′′′ groups of enzyme-bound neomycin B while the pKa of N6′ changes by 0.3 unit and N6′′′ experiences no shift. Isotopic solvent and heat capacity change studies strongly suggest differential effects and reorganization of solvent in kanamycin and neomycin class complexes of the enzyme. We also determined unusually high binding ΔCp values in the range of -0.7 to -3.8 kcal/mol·deg which were not explained by changes in the solvent accessible surface area. A break at 30°C was observed in the ΔCp plot and temperaturedependent backbone amide proton chemical shifts of four residues surrounding the binding site of kanamycin-APH(3′)-IIIa complex. These results may indicate specific solvent reorganization sites away from the binding site of the enzyme.

The mammalian Nell1 gene encodes a PKC-β1 binding protein that belongs to a new class of cell-signaling molecules controlling cell growth and differentiation. Overexpression of NELL1/Nell1 in the developing cranial sutures in both human and mouse induces craniosynostosis, the premature fusion of cranial sutures. This study describes the characterization of Nell16R (102DSJ), a recessive, neonatal-lethal point mutation in the mouse Nell1 gene, induced by N-ethyl-N-nitrosourea (ENU). The generation and sequencing of the mouse full-length cDNA (2862 bp) revealed that the Nell1 gene has an open reading frame of 2433 bp and encodes an 810 amino acid protein which is highly homologous to human and rat NELL1. Nell16R has a T→A base change that converts a codon for cysteine into a premature stop codon, resulting in severe truncation of the predicted protein product and marked reduction in steady state levels of the transcript. Immuno-histochemical analysis indicates that Nell1 is expressed in the vertebral column and is involved in osteoblast and chondrocyte differentiation. In addition to the expected alteration of cranial morphology, Nell16R mutants manifest skeletal defects in the vertebral column and ribcage, revealing a hitherto undefined role for Nell1 in signal transduction in endochondral ossification. Real-time quantitative RTPCR assays of 219 genes showed an association between the loss of Nell1 function and reduced expression of genes for extracellular matrix proteins critical for chondrogenesis and osteogenesis. Several affected genes are involved in the human cartilage disorder known as Ehlers-Danlos Syndrome (EDS) and other disorders associated with spinal curvature anomalies. Nell16R mutant mice are a new tool for elucidating basic mechanisms in osteoblast and chondrocyte differentiation in the developing skull and vertebral column and understanding how perturbations in the production of extracellular matrix proteins can lead to anomalies in these structures. The characterization of Nell1 functions using the Nell16R mouse model may further provide insights into the pathology of craniofacial defects like CS, cartilage diseases such as EDS as well as other bone and cartilage diseases.

The role of various polyglutamine (polyGln) aggregated states in the disease mechanism of expanded CAG repeat disorders continues to be a perplexing subject. We are interested in learning more about these species and the relationship between the aggregation pathways. We have developed an innovative staining technique that allows, for the first time, the visualization of small polyGln aggregates, which we refer to as aggregation foci (AF), that are functionally distinguished by their ability to serve as seeds for amyloid growth. The aggregation foci stain should prove useful in the Huntington’s disease research as a tool for the identification of a functional class of aggregates that was previously undescribed. The ability to account for different aggregates may provide a better correlation with neurodegeneration. Using this method we were able to detect at least four phenotypic classes of aggregates in stable PC12 cells engineered for inducible expression of different polyGln repeat length forms of a green fluorescent protein-fused huntingtin (htt) exon-1 fragment: 1) small, recruitment-competent, cytoplasmic AF, 2) large, cytoplasmic, perinuclear, green-fluorescent, recruitment-inert htt aggregates, 3) cytoplasmic, perinuclear, green-fluorescent, recruitment-competent aggregates, and 4) small, nuclear, recruitment-inert, green-fluorescent aggregates. Each species can be found either in isolation or co-existing within the same microscope field depending on the time post-induction and Gln repeat-length. In our studies, AF tend to be the earliest species that appear in the cells. The PC12 cells generally did not exhibit indications of toxicity due to the polyGln species, and thus provided a good model to study the aggregation pathway without the bias of cell death. Biochemical data were gathered to understand the properties of each distinct aggregate specie. We also examined the ability of two separate compounds (curcumin and demecolcine) to alter the aggregation pathway. Each experiment was designed to obtain knowledge about possible precursor/product relationships that exist among the species, with the ultimate goal of gaining insight into the aggregation pathways responsible for the formation of the amyloid-like AF and larger inert aggregates that arise in these the cell lines expressing various polyGln repeat-lengths. We interpret this data as indicating that the two species are on competing assembly pathways.

Atomic force microscopy (AFM) holds a unique position in microbiology because of its potential for nanometer (nm) scale imaging and piconewton (pN) force detection. These features can be exploited to characterize bacteria from the cellular down to the molecular level. In order to pursue such characterization studies, reliable sample preparation techniques must be developed. Spheroplasts are bacteria which have been treated with enzymes to remove cell wall components. Because the cytoplasmic membrane is exposed in spheroplasts, they are suitable for localizing transporters and other membrane proteins using AFM techniques. Constituents on the surface of intact bacteria are responsible for their adhesion to various substrates in vivo. The absence of these constituents in spheroplasts necessitates specialized immobilization strategies. This study presents a technique in which spheroplasts are immobilized by cross linking them with glutaraldehyde to mica surfaces pretreated with aminopropyltriethoxysilane. As suggested by the AFM images, this approach facilitates stable imaging in appropriate buffers. Because the sample preparation strategies presented are compatible with optical and atomic force microscopies, investigations in which molecular system components are monitored can be targeted. Evidence that the cells retain membrane integrity, continue glucose uptake, increase in diameter and initiate protein synthesis after immobilization is also presented. Based on this data, it is concluded that metabolic processes continue in immobilized spheroplasts. As a result of this finding, spheroplasts are proposed to be a platform for various imaging-based investigations. Elasticity and indentation measurements on intact bacteria and spheroplasts revealed significant differences between the two forms. They also provided the justification for using glutaraldehyde fixed spheroplasts for molecular recognition experiments designed to locate the glucose transporter on the surface of spheroplasts. An avidin-biotin system was used in which biotin was tethered to the AFM tip using a polyethylene glycol linker, When this functionalized tip probed spheroplast surfaces previously immunolabeled with a biotinylated antibody and avidin, molecular recognition was demonstrated. The fact that the biotin functionalized tips can be used in multiple applications is an attractive feature of this strategy. That results from AFM experiments can be validated with optical microscopy techniques is also an advantage.