6,603 research outputs found

    San Jacinto Intrusive Complex: 2. Geochemistry

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    Rocks from three large (>100^2 km) tonalitic intrusions exposed in the San Jacinto Mountains of southern California show a restricted compositional range of between 63 and 68 wt % SiO_2 for all but volumetrically minor felsic differentiates (with Si0_2≈70 wt %). All rocks with less than 65.5 wt % SiO_2 show linear element-element covariation. Felsic differentiates have characteristics (higher SiO_2, K_2O, Rb, Ba, U; higher and variable rare earth elements) consistent with derivation by in situ fractionation; rocks with between 65.5 and 70 wt % SiO_2 have intermediate characteristics and are interpreted as derived from liquids formed by mixing “primitive” liquids with fractionated liquids within an intermittently recharged, continuously solidifying magma chamber. Mafic inclusions extend the compositional trends of the mafic tonalites to 55 wt % SiO_2. The chemical variations of both inclusions and more mafic tonalites are interpreted as resulting from processes acting before injection of their parental liquids into the observed crustal magma chambers. Effects of chamber processes are minor for all but the most felsic rocks. The major effect of recharge is to buffer the thermal and chemical properties of liquids within the magma chambers, yielding large volumes of relatively homogeneous tonalite. For those elements where the bulk distribution coefficient is between about 0.5 and 2, concurrent recharge and solidification produces rocks that closely approximate the composition of the added liquids. Estimated Rayleigh numbers for these liquids are high (>10^(10)), implying convection throughout much of the solidification history of each chamber. Existence of trace element variations within analyzed rocks imply that convection was not totally efficient at homogenizing the various batches of liquid added to each chamber

    Many-body theory interpretation of deep inelastic scattering

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    We analyze data on deep inelastic scattering of electrons from the proton using ideas from standard many-body theory involving {\em bound} constituents subject to {\em interactions}. This leads us to expect, at large three-momentum transfer q{\bf{q}}, scaling in terms of the variable y~=νq\tilde{y}=\nu-{\bf |q|}. The response at constant q{\bf |q|} scales well in this variable. Interaction effects are manifestly displayed in this approach. They are illustrated in two examples.Comment: 10 pages, 4 figure

    The Effects of Absent Father Figures on the Social Functioning of Teens

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    Problem: In America, children under the age of 18 are being negatively affected by the absence of a father in the home. This is important because fatherlessness is on the rise (Census Bureau, 2016) and can harm a child’s future opportunities (Snyder, McLaughlin, & Findeis, 2006). Specifically, depressive symptoms and delinquent behavior have been recognized as two tangible outcomes of growing up without a father. Trending research suggests that delinquency and depressive symptoms are linked to a lack of parental monitoring (Markowitz & Ryan, 2016), yet the aspects of socialization (early father departure) and emotional distress (late father departure) should be further researched. Research Question: How does the level of social functioning in teens without father figures compare to teens with father figures? Design/sample: We will use a cross-sectional descriptive research design. Teens between the ages of 13-19 in enrolled in education, juvenile court/detention center, and local service agencies located in Miami Valley, Ohio will be studied using multistage cluster random sample. Collection/Analysis: A voluntary mobile-online survey will be sent out to the teachers, social workers in the court system and social workers at the social service agencies to distribute to their teenage students and clients. Three statistical tests will be run using SPSS software. Frequency distribution and Chi-square will compare teens living with a biological father, a father figure, or no father figure. One-way ANOVA will examine the differences in social functioning among teens with a biological father, father figure, or no father figure. Expected Findings: We expect to find higher social function in teens with an involved biological father who lives in the home. We also expect to find teens with father figures to have lower social functioning than those with biological fathers living in the home, while having higher social functioning than those with no biological father or father figure. Keywords: Father-figure, social functioning, teens, fatherless, biological fathe

    Yvan Lamonde — Histoire sociale des idées au Québec (1760-1896)

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    Parkinson\u27s Disease, Amantadine Hydrochloride Therapy and Dopa Metabolites

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    In an attempt to clarify the effect of amantadine hydrochloride therapy in Parkinson\u27s disease, dopa metabolites were measured in the urine of 15 patients who were taking this medication. The results indicated that patients on amantadine therapy had lower urinary levels of epinephrine plus norepinephrine than either normal individuals or parkinsonian patients not receiving amantadine. Patients who developed livedo reticularis during amantadine therapy showed a small but significant increase in urinary dopamine levels and a similar decrease in dopac levels, when compared to other patients on amantadine who did not develop livedo reticularis

    Calculation of Densities of States and Spectral Functions by Chebyshev Recursion and Maximum Entropy

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    We present an efficient algorithm for calculating spectral properties of large sparse Hamiltonian matrices such as densities of states and spectral functions. The combination of Chebyshev recursion and maximum entropy achieves high energy resolution without significant roundoff error, machine precision or numerical instability limitations. If controlled statistical or systematic errors are acceptable, cpu and memory requirements scale linearly in the number of states. The inference of spectral properties from moments is much better conditioned for Chebyshev moments than for power moments. We adapt concepts from the kernel polynomial approximation, a linear Chebyshev approximation with optimized Gibbs damping, to control the accuracy of Fourier integrals of positive non-analytic functions. We compare the performance of kernel polynomial and maximum entropy algorithms for an electronic structure example.Comment: 8 pages RevTex, 3 postscript figure
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