Confirmatory factor analysis of the Test of Performance Strategies (TOPS) among adolescent athletes

The aim of the present study was to examine the factorial validity of the Test of Performance Strategies (TOPS; Thomas et al., 1999) among adolescent athletes using confirmatory factor analysis. The TOPS was designed to assess eight psychological strategies used in competition (i.e. activation, automaticity, emotional control, goal-setting, imagery, negative thinking, relaxation and self-talk,) and eight used in practice (the same strategies except negative thinking is replaced by attentional control). National-level athletes (n = 584) completed the 64-item TOPS during training camps. Fit indices provided partial support for the overall measurement model for the competition items (robust comparative fit index = 0.92, Tucker-Lewis index = 0.88, root mean square error of approximation = 0.05) but minimal support for the training items (robust comparative fit index = 0.86, Tucker-Lewis index = 0.81, root mean square error of approximation = 0.06). For the competition items, the automaticity, goal-setting, relaxation and self-talk scales showed good fit, whereas the activation, emotional control, imagery and negative thinking scales did not. For the practice items, the attentional control, emotional control, goal-setting, imagery and self-talk scales showed good fit, whereas the activation, automaticity and relaxation scales did not. Overall, it appears that the factorial validity of the TOPS for use with adolescents is questionable at present and further development is required

Laser-induced fluorescence spectroscopy of the Ga-N[subscript 2] cluster

The first spectroscopic observation of the Ga–N[subscript 2] van der Waals cluster is reported. This was formed by laser ablation of a GaAs or GaP target followed by pulsed supersonic expansion in pure nitrogen. Laser-induced fluorescence spectra have revealed two strong band systems above 30000 cm[superscript -1]. The first, which has an onset at 33468 cm[superscript -1], is composed of eight observable members of a progression in the van der Waals stretching vibration. This has been assigned to the 2Δ–[X with combining tilde]2Π[subscript 3/2] transition correlating with the Ga 4s[superscript 2]4D[superscript 1] [superscript 2]D ← 4s[superscript 2]4p[superscript 1] [superscript 2]P[subscript 3/2] transition. A Birge–Sponer extrapolation gives a lower limit of 1270 cm[superscript -1] for the van der Waals binding energy in the excited state. At higher wavenumbers another prominent vibrational progression is observed which is attributed to a spin-forbidden transition correlating with the 4s[superscript 1]4p[superscript 2] [superscript 4]P ← 4s[superscript 2]4p[superscript 1] [superscript 2]P atomic asymptote, the cluster excited state most likely having [superscript 4]Σ[superscript -] symmetry. The excited state undergoes relatively slow spin–orbit-induced predissociation onto the repulsive [B with combining tilde][superscript 2]Σ[superscript +] potential surface followed by rapid emission from the Ga 4s[superscript 2]5s[superscript 1] [superscript 2]S dissociation product

Sc(iii) complexes with neutral N3- and SNS-donor ligands – a spectroscopic study of the activation of ethene polymerisation catalysts

Scandium trichloride complexes with tridentate N-3- and S2N-donor ligands (L-3) have been synthesised and characterised by IR, H-1, C-13{H-1} and Sc-45 NMR spectroscopy, microanalysis, and solid state and solution XAFS spectroscopy. Catalytic testing of a subset of these complexes with ethene has been undertaken in chlorobenzene with MMAO-3A and PMAO-IP at 60 degrees C and 40 bar ethene, giving low activity ethene polymerisation. The reactions of these complexes with MeLi and AlMe3 were studied by H-1, C-13{H-1}, Al-27 and Sc-45 NMR spectroscopy and in situ via Sc K-edge XAFS spectroscopy. Three or four mol. equivalents of MeLi react with [ScCl3(Me-3-tacn)] in THF solution to form [ScMe3(Me-3-tacn)] cleanly, while complexes of type [ScCl3(R-SNS)] {R-SNS = HN(CH2CH2SC10H21)(2)} form two different species proposed to be [ScMe3(R-SN(Li)S)] and [ScMe2(R-SN-S)]. In contrast, in situ Sc-45 NMR and Sc K-edge XAFS spectroscopic studies of the reaction of [ScCl3(Me-3-tacn)] with 10 mol. equivalents of AlMe3 strongly suggest that alkylation at the Sc(III) centre does not occur, instead retaining the Cl3N3 coordination environment and most likely forming Sc-Cl-AlMe3 bridging interactions. Similar studies on [ScCl3(decyl-SNS)] with 10 mol. equivalents of AlMe3 are also consistent with this, indicating that alkylation at the Sc centre does not occur except in the presence of co-catalyst [Ph3C][Al{OC(CF3)(3)}(4)] and the alpha-alkene, hex-1-ene

Confirmatory factor analysis of the thought occurrence questionnaire for sport (TOQS) among adolescent athletes

There is an inherent link between theory and measurement suggesting that validation of measures should be the first stage of theory testing. The aim of the present study was to cross-validate the factorial validity of the Thought Occurrence Questionnaire for Sport for use among adolescent athletes. National standard young athletes (Individual N_/204; Team N_/360) completed the TOQS questionnaire. Single-sample and multisample confirmatory factor analysis provided support for the psychometric integrity of the hypothesized three-factor correlated model. Multisample results demonstrated invariance for factor loadings and correlations between individual and team athletes. Internal consistency coefficients were over the .70 criterion for acceptability. Findings lend support to previous validation studies conducted on samples of adult athletes and suggest that the TOQS provides an equally valid measure for use among adolescent athletes. It is suggested that the TOQS can be used to investigate theoretical issues related to cognitive interference during competition

Formation of [Cr(CO)x(Ph2PN(iPr)PPh2)]+Structural Isomers by Reaction of Triethylaluminum with a ChromiumN,N-Bis(diarylphosphino)amine Complex [Cr(CO)4(Ph2PN(iPr)PPh2)]+: An EPR and DFT Investigation

The interaction of triethylaluminum (TEA) with a solution of the paramagnetic Cr(I) bis(phosphine) complex [Cr(CO)41][Al(OC(CF3)3)4] (1 = Ph2PN(iPr)PPh2) has been studied using EPR and DFT. It was found that the TEA is responsible for the complete removal of all CO groups from the [Cr(CO)41]+ complex, producing the [Cr(1-bis-η6-arene)]+, and this reaction occurs via a dominant pathway involving a series of [Cr(CO)x1]+ (x < 4) intermediates, consistently including the cis-[Cr(CO)31]+ complex (species A) and the “piano-stool”-type [Cr(CO)21]+ complex (species C). A further [Cr(CO)21]+ intermediate complex (labeled species D, which is a structural isomer of species C) was also identified experimentally, suggesting a second pathway for TEA activation may also be operative. All of these paramagnetic complexes have been characterized by CW EPR, and the spin Hamiltonian parameters were verified using DFT. The distribution and type of [Cr(CO)x1]+ intermediates formed were found to be very sensitive to the experimental conditions, including the quantity and manner of TEA addition, the temperature of activation, and the aging time of the solution