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Clinopyroxene–melt trace element partitioning experiments were carried out in the system Na 2 O–CaO–MgO–Al 2 O 3 –SiO 2 at pressures of 1, 2.3 and 3 GPa and temperatures of 1508 to 1811 K, to investigate the effects of temperature ( T ), pressure ( P ) and composition ( X ) on partition coefficients. Of particular interest were elements entering the octahedral M1-site. Ion probe analyses of run products produced crystal–melt partition coefficients ( D ) for 16 elements (Na, Ca, Al, Cl, Sc, Ti, Fe, Zr, In, La, Ce, Nd, Sm, Ho, Yb and Hf). With the exception of D Na , partition coefficients for all elements studied decrease with increased P and T , despite the concomitant increase in the Al content of the T-site. Fitting partition coefficients for isovalent series of cations to the elastic strain model of Blundy and Wood ( 1994 ) produced values for the site radius ( r 0 ), effective elastic modulus ( E ) and strain-free partition coefficient ( D 0 ). At each pressure, E values for the M1 and M2-sites increase with increasing Al concentration in the T-site . For a given bulk composition, E values decrease with increased T . The decrease in E with increasing T accounts for the remarkable constancy of the degree of fractionation between chemically similar elements, e.g. , over the range of pressures studied here. for our experiments is found to be higher than predicted by the Hazen and Finger ( 1979 ) relationship between elastic moduli and interatomic distance. This is explained by deformation of the M1-site polyhedron leading to relative displacement and kinking of the clinopyroxene T-site chains. We developed expressions for , , D Sc and D Ti as functions of P , T and composition. We show the feasibility of using calculated D Ti values in the prediction of D Zr and D Hf . Scandium and Ti partition coefficients were modelled based on the thermodynamic description for the crystal–melt exchange reaction and in terms of the energetics of the different charge-imbalanced configurations produced by insertion of a heterovalent trace cation. The resulting equations produce values of D Sc and D Ti that are within a factor of 2 of other experimentally determined values. Fits of the equations along the lherzolite solidus show that D Sc remains compatible in clinopyroxene at high pressure and that ratios of Zr/Hf and Ti/Eu should vary subtly with the pressure at which melting occurred.

Federal Communications Commission regulation of the satellite communications industry between 1965 and 1975 has been used in this paper to test the predictions of four theories of regulatory behavior--the interest group approach, the behavioral approach, the public interest approach, and the legislative control approach. A description of the institutional framework has been combined with statistical analysis of the 199 F.C.C. decisions that were made during this eleven year period. In the statistical analysis, the F.C.C. decisions were classified according to their impact on members of the communications industry, consumers, and other parties. Nonparametric statistical methods were then used to test the predictions of the four alternative theories. The analysis supports the legislative control theory of regulatory behavior. As a regulator of this industry in this period, the F.C.C. appears to have followed the wishes of the United States Congress as expressed in the Satellite Communications Act of 1962 and the Communications Act of 1934. Congress' desire for the expeditious creation of an international satellite communications system was supported by the F.C.C.'s favorable regulation of Comsat, while the instructions in the Communications Act of 1934 to serve the public interest, convenience, and necessity are reflected in the F.C.C.'s favorable regulation of consumers. The statistical analysis shows that the F.C.C. did not favor industry over consumers. Nor did it favor large firms over small ones, even large and allegedly influential firms such as AT&T. However, there appears to be a link between favorable regulation and firm size; favorable regulation seems to lead to growth in firm size rather than size leading to favorable regulation. The results of this analysis is significant for the design of public policy. In this case the behavior of the regulatory agency conformed to the desires of the legislature. The ability to control the agency reduces the uncertainty surrounding the implementation of public policy, making it less problematic. The mechanisms that permit Congressional control of the F.C.C.--tight control over the budget, the senior personnel, and the continued existence of the agency--could be applied in the implementation of other policies.

Fundamental Movement Skills (FMS) play a critical role in ontogenesis. Many children have insufficient FMS, highlighting the need for universal screening in schools. There are many observational FMS assessment tools, but their psychometric properties are not readily accessible. A systematic review was therefore undertaken to compile evidence of the validity and reliability of observational FMS assessments, to evaluate their suitability for screening. A pre-search of 'fundamental movement skills' OR 'fundamental motor skills' in seven online databases (PubMed, Ovid MEDLINE, Ovid Embase, EBSCO CINAHL, EBSCO SPORTDiscus, Ovid PsycINFO and Web of Science) identified 24 assessment tools for school-aged children that: (i) assess FMS; (ii) measure actual motor competence and (iii) evaluate performance on a standard battery of tasks. Studies were subsequently identified that: (a) used these tools; (b) quantified validity or reliability and (c) sampled school-aged children. Study quality was assessed using COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklists. Ninety studies were included following the screening of 1863 articles. Twenty-one assessment tools had limited or no evidence to support their psychometric properties. The Test of Gross Motor Development (TGMD, n = 34) and the Movement Assessment Battery for Children (MABC, n = 37) were the most researched tools. Studies consistently reported good evidence for validity, reliability for the TGMD, whilst only 64% of studies reported similarly promising results for the MABC. Twelve studies found good evidence for the reliability and validity of the Bruininks-Oseretsky Test of Motor Proficiency but poor study quality appeared to inflate results. Considering all assessment tools, those with promising psychometric properties often measured limited aspects of validity/reliability, and/or had limited feasibility for large scale deployment in a school-setting. There is insufficient evidence to justify the use of any observational FMS assessment tools for universal screening in schools, in their current form.