COMPARISON OF FORCE CURVES BETWEEN ON-WATER SINGLE SCULL ROWING AND THE ROWPERFECT ERGOMETER

The purpose of this study was to compare the RowPerfect ergometer to single scull rowing in order to validate its use in rowing training and crew selection. Eight national-level rowers were tested over three sets of 500 m, at stroke rates of 24, 26 and 28, on both the RowPerfect ergometer and on-water in a single scull. Blade force and oar angle were measured on-water while force and stroke length were measured on the ergometer. Both force and angle/length were normalised for comparison between the two forms of rowing. Co-efficient of multiple determination revealed high consistency levels for the 5 representative normalised stokes of each subject. Cross-correlation demonstrated high correlations between the force curves of the ergometer and on-water sculling. Thus, the results indicate that the RowPerfect ergometer successfully simulates on-water sculling

Interval timing in children:effects of auditory and visual pacing stimuli and relationships with reading and attention variables

Motor timing tasks have been employed in studies of neurodevelopmental disorders such as developmental dyslexia and ADHD, where they provide an index of temporal processing ability. Investigations of these disorders have used different stimulus parameters within the motor timing tasks which are likely to affect performance measures. Here we assessed the effect of auditory and visual pacing stimuli on synchronised motor timing performance and its relationship with cognitive and behavioural predictors that are commonly used in the diagnosis of these highly prevalent developmental disorders. Twenty- one children (mean age 9.6 years) completed a finger tapping task in two stimulus conditions, together with additional psychometric measures. As anticipated, synchronisation to the beat (ISI 329 ms) was less accurate in the visually paced condition. Decomposition of timing variance indicated that this effect resulted from differences in the way that visual and auditory paced tasks are processed by central timekeeping and associated peripheral implementation systems. The ability to utilise an efficient processing strategy on the visual task correlated with both reading and sustained attention skills. Dissociations between these patterns of relationship across task modality suggest that not all timing tasks are equivalent

Clinical and service implications of a cognitive analytic therapy model of psychosis

Cognitive analytic therapy (CAT) is an integrative, interpersonal model of therapy predicated on a radically social concept of self, developed over recent years in the UK by Anthony Ryle. A CAT-based model of psychotic disorder has been developed much more recently based on encouraging early experience in this area. The model describes and accounts for many psychotic experiences and symptoms in terms of distorted, amplified or muddled enactments of normal or ‘neurotic’ reciprocal role procedures (RRPs) and of damage at a meta-procedural level to the structures of the self. Reciprocal role procedures are understood in CAT to represent the outcome of the process of internalization of early, sign-mediated, interpersonal experience and to constitute the basis for all mental activity, normal or otherwise. Enactments of maladaptive RRPs generated by early interpersonal stress are seen in this model to constitute a form of ‘internal expressed emotion’. Joint description of these RRPs and their enactments (both internally and externally) and their subsequent revision is central to the practice of CAT during which they are mapped out through written and diagrammatic reformulations. This model may usefully complement and extend existing approaches, notably recent CBT-based interventions, particularly with ‘difficult’ patients, and generate meaningful and helpful understandings of these disorders for both patients and their treating teams. We suggest that use of a coherent and robust model such as CAT could have important clinical and service implications in terms of developing and researching models of these disorders as well as for the training of multidisciplinary teams in their effective treatment

Disruption of host-seeking behaviour by the salmon louse,Lepeophtheirus salmonis,using botanically derived repellents

The potential for developing botanically derived natural products as novel feed-through repellents for disrupting settlement of the salmon louse, Lepeophtheirus salmonis (Caligidae) upon farmed Atlantic salmon, Salmo salar, was investigated using an established laboratory vertical Y-tube behavioural bioassay for assessing copepodid behaviour. Responses to artificial sea water conditioned with the odour of salmon, or to the known salmon-derived kairomone component, α-isophorone, in admixture with selected botanical materials previously known to interfere with invertebrate arthropod host location were recorded. Materials included oils extracted from garlic, Allium sativum (Amaryllidaceae), rosemary, Rosmarinus officinalis (Lamiaceae), lavender, Lavandula angustifolia (Lamiaceae), and bog myrtle, Myrica gale (Myricaceae), and individual components (diallyl sulphide and diallyl disulphide from garlic; allyl, propyl, butyl, 4-pentenyl and 2-phenylethyl isothiocyanate from plants in the Brassica genus). Removal of attraction to salmon-conditioned water (SCW) or α-isophorone was observed when listed materials were presented at extremely low parts per trillion (ppt), that is picograms per litre or 10−12 level. Significant masking of attraction to SCW was observed at a level of 10 ppt for diallyl disulphide and diallyl sulphide, and allyl isothiocyanate and butyl isothiocyanate. The potential of very low concentrations of masking compounds to disrupt Le. salmonis copepodid settlement on a host fish has been demonstrated in vitro

Sustainable risk management of emerging contaminants in municipal wastewaters

This article is available open access through the publisher’s website at the link below. Copyright @ 2009 The Royal Society.The presence of emerging contaminants in municipal wastewaters, particularly endocrine-disrupting compounds such as oestrogenic substances, has been the focus of much public concern and scientific attention in recent years. Due to the scientific uncertainty still surrounding their effects, the Precautionary Principle could be invoked for the interim management of potential risks. Therefore, precautionary prevention risk-management measures could be employed to reduce human exposure to the compounds of concern. Steroid oestrogens are generally recognized as the most significant oestrogenically active substances in domestic sewage effluent. As a result, the UK Environment Agency has championed a ‘Demonstration Programme’ to investigate the potential for removal of steroid oestrogens and alkylphenol ethoxylates during sewage treatment. Ecological and human health risks are interdependent, and ecological injuries may result in increased human exposures to contaminants or other stressors. In this context of limiting exposure to potential contaminants, examining the relative contribution of various compounds and pathways should be taken into account when identifying effective risk-management measures. In addition, the explicit use of ecological objectives within the scope of the implementation of the EU Water Framework Directive poses new challenges and necessitates the development of ecosystem-based decision tools. This paper addresses some of these issues and proposes a species sensitivity distribution approach to support the decision-making process related to the need and implications of sewage treatment work upgrade as risk-management measures to the presence of oestrogenic compounds in sewage effluent

Identification and application of bacterial volatiles to attract a generalist aphid parasitoid from laboratory to greenhouse assays

BACKGROUND: Recent studies have shown that microorganisms emit volatile compounds that affect insect behaviour. However, it remains largely unclear whether microbes can be exploited as a source of attractants to improve biological control of insect pests. In this study, we used a combination of coupled gas chromatography electroantennography (GC-EAG) and Y-tube olfactometer bioassays to identify attractive compounds in the volatile extracts of three bacterial strains that are associated with the habitat of the generalist aphid parasitoid Aphidius colemani, and to create mixtures of synthetic compounds to find attractive blends for A. colemani. Subsequently, the most promising blend was evaluated in two-choice cage experiments under greenhouse conditions. RESULTS: GC-EAG analysis revealed 20 compounds that were linked to behaviourally attractive bacterial strains. A mixture of two EAG-active compounds, styrene and benzaldehyde applied at a respective dose of 1 μg and 10 ng, was more attractive than the single compounds or the culture medium of the bacteria in Y-tube olfactometer bioassays. Application of this synthetic mixture under greenhouse conditions resulted in significant attraction of the parasitoids, and outperformed application of the bacterial culture medium. CONCLUSION: Compounds isolated from bacterial blends were capable of attracting parasitoids both in laboratory and greenhouse assays, indicating that microbial culture are an effective source of insect attractants. This opens new opportunities to attract and retain natural enemies of pest species and to enhance biological pest control

Changes in concentration of isoflavonoids after cis-jasmone spraying in the leaves of two soybean cultivars.

cis-jasmone is a naturally-occurring compound in plants that activates direct and indirect defence in model and crop plants'". Exogenous application of cis-jasmone increases flavonoid concentrations in soybean and affects negatively Anticarsia gemmatalis weight gain. Here, foliar isoflavonoid concentrations were evaluated after cis-jasmone spraying on soybean cultivars BRS l34 and lAC 100, grown at Embrapa Soybean greenhouse facilities. At V) development stage, plants were sprayed with water, Tween 20 + water or cis-jasmone + tween 20 + water. For flavonoid extraction, leaves were collected 12, 24, 48, 96, and 120h after spraying, and immediately frozen in liquid nitrogen, ground in a mortar and extracted in MeOH 90% or EtOH 80% + HCI (0.001 M). Isoflavonoid concentrations were estimated by HPLC analysis. The extracts obtained from leaves of both genotypes of 24 h cis-jasmone treated plants presented higher quantities of daidzin, malonyl-daidzin, glycitin, malonyl-glycitin, glycitein and genistin, when compared to water and Tween 20 + water treated plants. Daidzein was present in hígh concentration, in both cultivars, 24 h and 48 h after cis-jasmone spraying, but no longer detected in samples collected 120 h after treatment. Coumesterol was detected, but only from samples collected 48 h after spraying. It is possible that such increases may be related to the decrease in daidzein concentration, considering that this compound is involved in coumesterol synthesis. Comparing solvent efficiencies, EtOH 80% + HCI (0.001 M) presented higher extraction capacity than MeOH 90%; coumestrol concentration in ethanolic extracts was approximately twice as high as in methanolic extracts. Our results indicated that cis-jasmone induces the production of non-volatile compounds in soybean such as isoflavonoids, and that EtOH 80% + HCI (O.OOIM)extraction is more efficient when compared to MeOH 90%