2,188 research outputs found
Rhizosphere Ph and Phosphatase Activity in Orthic Allophanic Soil Under Pinus Radiata Seedlings Grown with Broom and Ryegrass
Under Pinus radiata plantations where the tree spacing is wider and most soils are phosphorus (P) deficient, the radiata tree response to P fertilizer is expected to be more influenced by the interaction between the applied P fertilizer, the tree and understorey vegetation. Therefore, a better understanding of the soil P chemistry under radiata pine trees in association with other plants is required. We investigated the effect of broom (Cytisus scoparius L.) and ryegrass (Lolium multiflorum) grown with radiata seedlings in Orthic Allophanic Soil treated with 0, 50, and 100 μg P g-1 soil of TSP on the pH and phosphatase activity in the rhizosphere soils under glasshouse condition. The pHs of radiata rhizosphere soils either grown with broom or grass were lower than those in the bulk soils and the bulk and rhizosphere soils of grass and broom, whether they were grown alone or grown with radiata at the applications of 50 and 100 μg P g-1 soil. These results suggest that P application enhanced root induced acidification in a P-deficient Allophanic Soil under radiata. The soils in the rhizosphere of grass and broom, grown in association with radiata, were also acidified by the effect of radiata roots. Acid phosphatase activity in soils under radiata, grass and broom decreased with an increased rate of P application. At all P rates, acid phosphatase activity was higher in the rhizosphere of radiata grown with broom than in the bulk soils. The phosphatase activity in the rhizosphere soil of radiata grown with broom was also higher than that of radiata grown with grass, but it was slightly lower than that in the rhizosphere of broom grown alone. These results suggest that broom may have also contributed to the higher phosphatase activity in the rhizosphere soils than in the bulk soils of broom and radiata when they were grown togethe
Effects of Co substitution on thermodynamic and transport properties and anisotropic in Ba(FeCo)As single crystals
Single crystalline samples of Ba(FeCo)As with
have been grown and characterized via microscopic, thermodynamic and transport
measurements. With increasing Co substitution, the thermodynamic and transport
signatures of the structural (high temperature tetragonal to low temperature
orthorhombic) and magnetic (high temperature non magnetic to low temperature
antiferromagnetic) transitions are suppressed at a rate of roughly 15 K per
percent Co. In addition, for superconductivity is stabilized,
rising to a maximum of approximately 23 K for and
decreasing for higher values. The phase diagram for
Ba(FeCo)As indicates that either superconductivity can
exist in both low temperature crystallographic phases or that there is a
structural phase separation. Anisotropic, superconducting, upper critical field
data () show a significant and clear change in anisotropy between
samples that have higher temperature structural phase transitions and those
that do not. These data show that the superconductivity is sensitive to the
suppression of the higher temperature phase transition
\u3ci\u3eGopherus polyphemus\u3c/i\u3e (Gopher Tortoise), \u3ci\u3eCtenosaura similis\u3c/i\u3e (Gray\u27s Spiny-Tailed Iguana) Predation
Gopherus polyphemus is currently listed as a threatened and protected species in the state of Florida (Mushinsky et al. 2006. In Meylan led.], Biology and Conservation of Florida Turtles, pp. 350-375. Chelonian Research Monographs 3). Documented natural predators of Gopherus polyphemus include the Raccoon (Procyon lotor), Gray Fox (Urocyon cinereoargenteris), Striped Skunk (Mephitus mephitis), Opposum (Didelphis virginianus), Armadillo (Dasypus novemcinctus),and crows (Corvus sp.) (Mushinsky et al., op. cit. ), and the introduced Savaunah Monitor (Varanus exanthematicus) (Owens et al. 2005. Herpetol. Rev. 3657-58). Herein, we augment this list to include the nonindigenous Gray\u27s Spiny-tailed Iguana (Ctenosaura similis)
Vulture-Cattle Interactions at a Central Florida Ranch
Black vulture depredations to newborn livestock, poultry, and other captive animals have been reported from at least 15 states, and during the 1990s, reports of depredations increased annually by an average of 18%. In response to this issue, we initiated a study at Buck Island Ranch of the MacArthur Agro-Ecology Research Center in central Florida to examine interactions between cattle and vultures. Based on previous reports, we hypothesized that vulture predation selectively targets calves of young, inexperienced cows. To document vulture activity, we conducted point counts of vultures in pastures throughout the ranch from January 2000 to March 2001. During point counts, turkey vultures accounted for 78% of the observations compared to 22% for black vultures. We noted that vultures used certain pastures preferentially, with over 70% of the vultures in 3 pastures where heifers were calving and the remainder spread among 7 pastures containing yearling heifers only or cows and calves. Turkey and black vultures were often present during the 19 calving events we observed, but usually neither species exhibited threatening behavior toward calves or calving heifers. Instead, the birds seemed intent on gaining access to the afterbirth. On one occasion, however, we observed an attempted depredation by black vultures on a calf as it was being born. The cow was able to chase the buds off, however, and the birth proceeded successfully. We conclude that predation by black vultures occurs when the buds identify and then exploit vulnerable animals, although there is still much to be learned regarding the circumstances that promote such activity. b e n t management recommendations include dispersing nearby black vulture roosts and providing careful oversight to protect inexperienced cows that are first-time breeders
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A Comparison of Drawings Between a Group of Dyslexic Adolescents and a Group of Non-Dyslexic Adolescents
The purpose of this paper is to compare a group of adolescents with the learning disorder of dyslexia and a group of adolescents without dyslexia in regard to their ability to make realistic drawings. Subjects selected for the study were from a suburban junior high school in which a random sample was taken of both dyslexic and non-dyslexic students. Each was given three standardized drawing tasks, including a still-life drawing, a contour drawing, and a perspective drawing. The drawings were judged by five evaluators on a continuum of realistic to non-realistic. The ratings were then analyzed by the application of the Mann-Whitney U-Test, which indicated that there are no significant differences in the abilities of the two groups to render drawings realistically
Momentum dependence of the superconducting gap in NdFeAsO1-xFx single crystals measured by angle resolved photoemission spectroscopy
We use angle resolved photoemission spectroscopy (ARPES) to study the
momentum dependence of the superconducting gap in NdFeAsO1-xFx single crystals.
We find that the Gamma hole pocket is fully gapped below the superconducting
transition temperature. The value of the superconducting gap is 15 +- 1.5 meV
and its anisotropy around the hole pocket is smaller than 20% of this value.
This is consistent with an isotropic or anisotropic s-wave symmetry of the
order parameter or exotic d-wave symmetry with nodes located off the Fermi
surface sheets. This is a significant departure from the situation in the
cuprates, pointing to possibility that the superconductivity in the iron
arsenic based system arises from a different mechanism.Comment: 4 pages, 3 figure
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Title IX and the Cleary Act: What Counselor Educators Must Know
Because of the far-reaching legal, monetary, academic, and public relations ramifications of the sex abuse scandal at Pennsylvania State University, campus administrators are reviewing and more strictly enforcing the mandatory reporting requirements of Title IX of the 1972 Education Amendments and the Clery Act related to sexual harassment and sexual violence. This creates challenges in didactic and clinical coursework for counselor educators who must balance adhering to university reporting guidelines with the ethical responsibilities to provide informed consent and maintain confidentially of information disclosed by students and their clients during training. Issues involved for counselor educators and student counselors-in-training, the process of securing appropriate exceptions to mandatory reporting, and a sample exception policy are presented
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