Associations between coronal mass ejections and interplanetary shocks

Nearly continuous complementary coronal observations and interplanetary plasma measurements for the years 1979-1982 are compared. It is shown that almost all low latitude high speed coronal mass ejections (CME's) were associated with shocks at HELIOS 1. Some suitably directed low speed CME's were clearly associated with shocks while others may have been associated with disturbed plasma (such as NCDE's) without shocks. A few opposite hemisphere CME's associated with great flares seem to be associated with shocks at HELIOS

Caveolin contributes to the modulation of basal and β-adrenoceptor stimulated function of the adult rat ventricular myocyte by simvastatin: A novel pleiotropic effect

The number of people taking statins is increasing across the globe, highlighting the Importance of fully understanding statins effects on the cardiovascular system. The beneficial impact of statins extends well beyond regression of atherosclerosis to include direct effects on tissues of the cardiovascular system (pleiotropic effects). Pleiotropic effects on the cardiac myocyte are often overlooked. Here we consider the contribution of the caveolin protein, whose expression and cellular distribution is dependent on cholesterol, to statin effects on the cardiac myocyte. Caveolin is a structural and regulatory component of caveolae, and is a key regulator of cardiac contractile function and adrenergic responsiveness. We employed an experimental model in which inhibition of myocyte HMG CoA reductase could be studied in the absence of paracrine influences from non-myocyte cells. Adult rat ventricular myocytes were treated with 10 μM simvastatin for 2 days. Simvastatin treatment reduced myocyte cholesterol, caveolin 3 and caveolar density. Negative inotropic and positive lusitropic effects (with corresponding changes in [Ca2]¡) were seen in statin-treated cells. Simvastatin significantly potentiated the inotropic response to β2-, but not β1-, adrenoceptor stimulation. Under conditions of β2-adrenoceptor stimulation, phosphorylation of phospholamban at Ser16and troponin I at Ser23/24was enhanced with statin treatment. Simvastatin increased NO production without significant effects on eNOS expression or phosphorylation (Ser1177), consistent with the reduced expression of caveolin 3, its constitutive Inhibitor. In conclusion, statin treatment can reduce caveolin 3 expression, with functional consequences consistent with the known role of caveolae in the cardiac cell. These data are likely to be of significance, particularly during the early phases of statin treatment, and in patients with heart failure who have altered ß-adrenoceptor signalling. In addition, as caveolin is ubiquitously expressed and has myriad tissue-specific functions, the impact of statin-dependent changes in caveolin is likely to have many other functional sequelae

How is female mate choice affected by male competition?

Author Posting. © Cambridge Philosophical Society, 2005. This article is posted here by permission of Cambridge Philosophical Society for personal use, not for redistribution. The definitive version was published in Biological Reviews 80: (2005) 559-571, doi:10.1017/S1464793105006809.The plethora of studies devoted to the topics of male competition and female mate choice belie the fact that their interaction remains poorly understood. Indeed, on the question of whether competition should help or hinder the choice process, opinions scattered throughout the sexual selection literature seem unnecessarily polarised. We argue, in the light of recent theoretical and empirical advances, that the effect of competition on mate choice depends on whether it results in the choosy sex attaining high breeding value for total fitness, considering both direct and indirect fitness benefits. Specifically, trade-offs may occur between different fitness benefits if some are correlated with male competitive ability whilst others are not. Moreover, the costs and benefits of mating with competitive males may vary in time and/or space. These considerations highlight the importance of injecting a life-history perspective into sexual selection studies. Within this context, we turn to the sexual selection literature to try to offer insights into the circumstances when competition might be expected to have positive or negative implications for pre-copulatory female choice. In this regard, we elaborate on three stages where competition might impact upon the choice process: (i) during mate detection, (ii) mate evaluation, and (iii) in dictating actual mating outcomes. We conclude by offering researchers several potentially rewarding avenues for future research.This study was supported by an Australian Postgraduate Award, a Sir Keith Murdoch Fellowship, and a Centre for International Mobility Fellowship (to B.B.M.W) and the Academy of Finland (to U.C.)

The heritability of mating behaviour in a fly and its plasticity in response to the threat of sperm competition.

Phenotypic plasticity is a key mechanism by which animals can cope with rapidly changeable environments, but the evolutionary lability of such plasticity remains unclear. The socio-sexual environment can fluctuate very rapidly, affecting both the frequency of mating opportunities and the level of competition males may face. Males of many species show plastic behavioural responses to changes in social environment, in particular the presence of rival males. For example, Drosophila pseudoobscura males respond to rivals by extending mating duration and increasing ejaculate size. Whilst such responses are predicted to be adaptive, the extent to which the magnitude of response is heritable, and hence selectable, is unknown. We investigated this using isofemale lines of the fruit fly D. pseudoobscura, estimating heritability of mating duration in males exposed or not to a rival, and any genetic basis to the change in this trait between these environments (i.e. degree of plasticity). The two populations differed in population sex ratio, and the presence of a sex ratio distorting selfish chromosome. We find that mating duration is heritable, but no evidence of population differences. We find no significant heritability of plasticity in mating duration in one population, but borderline significant heritability of plasticity in the second. This difference between populations might be related to the presence of the sex ratio distorting selfish gene in the latter population, but this will require investigation in additional populations to draw any conclusions. We suggest that there is scope for selection to produce an evolutionary response in the plasticity of mating duration in response to rivals in D. pseudoobscura, at least in some populations

The 5x1 DAFNE Study Protocol: A cluster randomised trial comparing a standard 5 day DAFNE course delivered over 1 week against DAFNE training delivered over 1 day a week for 5 consecutive weeks.

Background Structured education programmes are now established as an essential component to assist effective self-management of diabetes. In the case of Type 1 diabetes, the Dose Adjustment For Normal Eating (DAFNE) programme improves both glycaemic control and quality of life. Traditionally delivered over five consecutive days, this format has been cited as a barrier to participation by some patients, such as those who work full-time. Some centres in the UK have organised structured education programmes to be delivered one day a week over several consecutive weeks. This type of format may add benefit by allowing more time in which to practice skills between sessions, but may suffer as a result of weaker peer support being generated compared to that formed over five consecutive days. Methods/design We aim to compare DAFNE delivered over five consecutive days (1 week course) with DAFNE delivered one day a week over five weeks (5 week course) in a randomised controlled trial. A total of 213 patients were randomised to attend either a 1 week or a 5 week course delivered in seven participating centres. Study outcomes (measured at baseline, 6 and 12 months post-course) include HbA1c, weight, self-reported rates of severe hypoglycaemia, psychosocial measures of quality of life, and cost-effectiveness. Generalisability was optimised by recruiting patients from DAFNE waiting lists at each centre, and by mailing eligible patients from hospital clinic lists. The inclusion and exclusion criteria were identical to those used to recruit to a standard DAFNE course (e.g., HbA1c <12%, with no lower limit). Qualitative interviews were undertaken with a sub-sample of n=30 patients and their course educators (n=11) to help understand and interpret differences and similarities in outcomes between the two arms, and to identify logistical problems and unanticipated issues arising from the adaptation and delivery of a 5 week course. Discussion This trial has been designed to test the hypothesis that the benefits of delivering a structured education programme over 5 weeks are comparable to those observed after a 1 week course. The results of the trial and the qualitative sub-study will both inform the design and delivery of future DAFNE courses, and the development of structured education programmes in other fields of medicine

A female-emitted pheromone component is associated with reduced male courtship in the parasitoid wasp Spalangia endius

During courtship interactions, the courted individual may not always be prepared to mate. For example, mating or courtship may be detrimental to its fitness and resistance is expected under these circumstances. As such, various resistance strategies have evolved, from physically fending off courting individuals to producing behavioural signals of unreceptivity. In the parasitoid wasp Spalangia endius, females rarely re-mate and mated females are avoided by males in favour of virgin females. Further, mated females appear to advertise their mating status by the release of a pheromone component (methyl 6-methylsalicylate), but direct evidence of the nature of this release is lacking. Here we used real-time chemical analysis to track the emission of the pheromone component during courtship interactions between virgin males and either virgin or mated females. We found that females actively release methyl 6-methylsalicylate when courted and that significantly greater concentrations are released by previously mated females. Further, high concentrations of this component are associated with both the prevention and termination of courtship