New and interesting Campylopus records from South Africa

New records are presented based on a collection of Campylopus specimens made by the second author in the Western Cape Province of South Africa. The austral species Campylopus clavatus (R. Brown) Wils. in Hook. and Campylopus vesticaulis Mitt. are reported for the first time for Africa, and Campylopus acuminatus Mitt. var. kirkii (Mitt.) J.-P. Frahm is recorded for the second time for Africa. Campylopus arctocarpus (Hornsch.) Mitt. ssp. madegassus (Besch.) J.-P. Frahm is reported for the first time for the Republic of South Africa, and this is the southernmost record of this species. Campylopus simii Schelpe is not synonymous with C. julaceus Jaeg. ssp. arbogastii (Ren. & Card.) J.-P. Frahm but combined here as new as a variety of C. pilifer Brid

Normative values for the profile of mood states for use with athletic samples

The Profile of Mood States (POMS) has been used extensively for the assessment of mood in the sport and exercise environments. The purpose of the study was to develop tables of normative values based on athletic samples. Participants (N = 2,086), comprising athletes at the international (n = 622), club (n = 628), and recreational (n = 836) levels, completed the POMS in one of three situations: pre-competition/exercise, post-competition/exercise, and away from the athletic environment. Differences between the athletic sample and existing norms were found for all mood subscales. Main effects of level of competition and situation were identified. The results support the proposition that the use of the original tables of normative values in sport and exercise environments is inappropriate

Frequency Space Correlation Between REITs and Capital Market Indices

Several studies have examined real estate investment trust (REIT) co-movement with stocks or bonds using traditional time domain based methods, such as linear regression or correlation. Results of these studies have produced inconsistent statistical model parameters. The erratic behavior of the models may have resulted from the different time periods in the studies, the REITs included in a study or the market indices. Another factor contributing to the variation of the models comes from the compression of cyclical information over a study?s time period by time domain based techniques. Cross-spectral analysis provides a frequency space method of examining the coherency (i.e., frequency space correlation) between two time series across all frequencies. This article contains an examination of the coherency between REITs and stock market indices and REITs and U.S. Treasury debt indices for the period 1989-95. Results of the coherency spectra show significant co-movement between REITs and stock market indices, while debt instruments show very few frequencies with significant coherency. Furthermore, phase spectra provide evidence of contemporaneous movement between REITs and stock indices at all frequencies.

Introduction to the Special Issue: The AgentLink III Technical Forums

This article introduces the special issue of ACM Transactions on Autonomous and Adaptive Systems devoted to research papers arising from the three Technical Forum Group meetings held in 2004 and 2005 that were organized and sponsored by the European FP6 Coordination Action AgentLink III

Re-evaluation of the factorial validity of the Revised Competitive State Anxiety Inventory-2

Anxiety is one of the most frequently researched constructs in the field of sport and exercise psychology. Although there are at least 22 published scales available to measure anxiety (see Ostrow, 1996), the Competitive State Anxiety Inventory-2 (CSAI-2: Martens, Burton, Vealey, Bump, & Smith, 1990) has generally been the scale of choice since its development. Given its prominence as a research tool, indeed it was described by Woodman and Hardy (2003, p.453) as having 'near sine qua non status', the CSAI-2 has naturally been the subject of considerable scrutiny of its psychometric characteristics. Several studies have now been published which have raised concerns about the factorial validity of the CSAI-2 in its English (Cox, Martens, & Russell, 2003; Lane, Sewell, Terry, Bartram, & Nesti, 1999), Greek (Tsorbatzoudis, Varkoukis, Kaissidis-Rodafinos, & Grouios, 1998), and Swedish (Lundqvist & Hassmen, in press) versions. Collectively, reevaluations of its psychometric properties have raised serious doubts about the validity of the CSAI-2 in its original form and by implication have cast a shadow over the findings of dozens of studies that have used it to measure anxiety. To address this situation, Cox et al. (2003) conducted a two-stage process using calibration and validation samples to arrive at an improved measure. Having deleted problematic items in the original CSAI-2 and having subsequently supported the factorial validity of a revised version of the measure, termed the CSAI-2R, they recommended that researchers and clinicians should in future use the revised measure in preference to the original. The purpose of the present study was to re-evaluate the factorial validity of the CSAI-2R, as recommended by Cox and colleagues. Considering the potential for the revised measure to become the new scale of choice for researchers in the sport and exercise domains, this is judged to be an important contribution to the anxiety literature

An Invariance Principle for Maintaining the Operating Point of a Neuron

Sensory neurons adapt to changes in the natural statistics of their environments through processes such as gain control and firing threshold adjustment. It has been argued that neurons early in sensory pathways adapt according to information-theoretic criteria, perhaps maximising their coding efficiency or information rate. Here, we draw a distinction between how a neuron’s preferred operating point is determined and how its preferred operating point is maintained through adaptation. We propose that a neuron’s preferred operating point can be characterised by the probability density function (PDF) of its output spike rate, and that adaptation maintains an invariant output PDF, regardless of how this output PDF is initially set. Considering a sigmoidal transfer function for simplicity, we derive simple adaptation rules for a neuron with one sensory input that permit adaptation to the lower-order statistics of the input, independent of how the preferred operating point of the neuron is set. Thus, if the preferred operating point is, in fact, set according to information-theoretic criteria, then these rules nonetheless maintain a neuron at that point. Our approach generalises from the unimodal case to the multimodal case, for a neuron with inputs from distinct sensory channels, and we briefly consider this case too