Scientific Opinion on the evaluation of the safety in use of Yohimbe (Pausinystalia yohimbe (K. Schum.) Pierre ex Beille)

The Panel on Food Additives and Nutrient Sources added to Food provides a scientific opinion evaluating the safety in use of yohimbe bark and its preparations originating from Yohimbe (Pausinystalia yohimbe (K. Schum.) Pierre ex Beille when used in food, e.g. in food supplements. The bark of the plant contains a number of indole alkaloids of biological relevance and preparations of yohimbe bark have been traditionally used as general tonic, performance enhancer and as an aphrodisiac. Food supplements containing yohimbe bark preparations are available nowadays, especially via internet retail. Yohimbine, the major alkaloid of yohimbe bark and raubasine, another alkaloid occurring in lower concentrations in the bark, are used as active ingredients in a number of medicinal products for which adverse effects are described. The Panel reviewed the available scientific data on a possible association between the intake of yohimbe bark and its preparations and potential harmful effects on health. When those data were not available, priority was given to yohimbine, as the only alkaloid for which occurrence had been shown and quantified in food supplements containing yohimbe bark. The Panel concluded that the chemical and toxicological characterisation of yohimbe bark and its preparations for use in food are not adequate to conclude on their safety as ingredients of food, e.g. in food supplements. Thus the Panel could not provide advice on a daily intake of yohimbe bark and its preparations that do not give rise to concerns about harmful effects to health. An estimation of exposure to yohimbine from food supplements was performed showing that theoretical maximum daily intake may exceed the maximum approved daily dose of yohimbine from use as a medicinal product

Optical Trapping with High Forces Reveals Unexpected Behaviors of Prion Fibrils

Amyloid fibrils are important in diverse cellular functions, feature in many human diseases and have potential applications in nanotechnology. Here we describe methods that combine optical trapping and fluorescent imaging to characterize the forces that govern the integrity of amyloid fibrils formed by a yeast prion protein. A crucial advance was to use the self-templating properties of amyloidogenic proteins to tether prion fibrils, enabling their manipulation in the optical trap. At normal pulling forces the fibrils were impervious to disruption. At much higher forces (up to 250 pN), discontinuities occurred in force-extension traces before fibril rupture. Experiments with selective amyloid-disrupting agents and mutations demonstrated that such discontinuities were caused by the unfolding of individual subdomains. Thus, our results reveal unusually strong noncovalent intermolecular contacts that maintain fibril integrity even when individual monomers partially unfold and extend fibril length.National Institutes of Health (U.S.) (Grant GM025874)National Science Foundation (U.S.). CAREER (Award 0643745

Applying Bayesian model averaging for uncertainty estimation of input data in energy modelling

Background Energy scenarios that are used for policy advice have ecological and social impact on society. Policy measures that are based on modelling exercises may lead to far reaching financial and ecological consequences. The purpose of this study is to raise awareness that energy modelling results are accompanied with uncertainties that should be addressed explicitly. Methods With view to existing approaches of uncertainty assessment in energy economics and climate science, relevant requirements for an uncertainty assessment are defined. An uncertainty assessment should be explicit, independent of the assessor’s expertise, applicable to different models, including subjective quantitative and statistical quantitative aspects, intuitively understandable and be reproducible. Bayesian model averaging for input variables of energy models is discussed as method that satisfies these requirements. A definition of uncertainty based on posterior model probabilities of input variables to energy models is presented. Results The main findings are that (1) expert elicitation as predominant assessment method does not satisfy all requirements, (2) Bayesian model averaging for input variable modelling meets the requirements and allows evaluating a vast amount of potentially relevant influences on input variables and (3) posterior model probabilities of input variable models can be translated in uncertainty associated with the input variable. Conclusions An uncertainty assessment of energy scenarios is relevant if policy measures are (partially) based on modelling exercises. Potential implications of these findings include that energy scenarios could be associated with uncertainty that is presently neither assessed explicitly nor communicated adequately

How does Brazil measure up? Comparing rankings through the lenses of nation brand indexes

A considerable amount of literature has been published on nation brand and yet not much regarding measurement. The purpose of this paper is to examine nation brand indexes and explore the unbalanced outcomes of a country’s position in these recognized instruments. Although research has been carried out on nation brand, no single study exists comparing a country in four diverse nation brand indexes, which are the reputable ones by Anholt (2007), Fetscherin (2010), Fombrun (2014) and Anholt and Govers (2014). This paper also reflects on the critical studies perspective of the place branding research domain, discussed by Lucarelli and Berg (2011). After a qualitative approach applied to Brazil, it is believed that these indexes mutually support and complement each other - even though they use different approaches, methodologies, samples, and data. Moreover, each of them has their own strengths and weaknesses in terms of accuracy and rationality. Findings from this paper’s evaluation may guide nation brand managers, governments, and researchers to recognize that indexes should be taken into account when analysing a nation brand and its complex image. Therefore, this paper contributes to existing knowledge on the critical studies perspective of the contemporary theoretical structure of the place branding research domain by providing a comparative study based on real data-based rankings of nation brand indexes

Conceiving “personality”: Psychologist’s challenges and basic fundamentals of the Transdisciplinary Philosophy-of-Science Paradigm for Research on Individuals

Scientists exploring individuals, as such scientists are individuals themselves and thus not independent from their objects of research, encounter profound challenges; in particular, high risks for anthropo-, ethno- and ego-centric biases and various fallacies in reasoning. The Transdisciplinary Philosophy-of-Science Paradigm for Research on Individuals (TPS-Paradigm) aims to tackle these challenges by exploring and making explicit the philosophical presuppositions that are being made and the metatheories and methodologies that are used in the field. This article introduces basic fundamentals of the TPS-Paradigm including the epistemological principle of complementarity and metatheoretical concepts for exploring individuals as living organisms. Centrally, the TPS-Paradigm considers three metatheoretical properties (spatial location in relation to individuals’ bodies, temporal extension, and physicality versus “non-physicality”) that can be conceived in different forms for various kinds of phenomena explored in individuals (morphology, physiology, behaviour, the psyche, semiotic representations, artificially modified outer appearances and contexts). These properties, as they determine the phenomena’s accessibility in everyday life and research, are used to elaborate philosophy-of-science foundations and to derive general methodological implications for the elementary problem of phenomenon-methodology matching and for scientific quantification of the various kinds of phenomena studied. On the basis of these foundations, the article explores the metatheories and methodologies that are used or needed to empirically study each given kind of phenomenon in individuals in general. Building on these general implications, the article derives special implications for exploring individuals’ “personality”, which the TPS-Paradigm conceives of as individual-specificity in all of the various kinds of phenomena studied in individuals

The interpretations and uses of fitness landscapes in the social sciences

__Abstract__ This working paper precedes our full article entitled “The evolution of Wright’s (1932) adaptive field to contemporary interpretations and uses of fitness landscapes in the social sciences” as published in the journal Biology & Philosophy (http://link.springer.com/article/10.1007/s10539-014-9450-2). The working paper features an extended literature overview of the ways in which fitness landscapes have been interpreted and used in the social sciences, for which there was not enough space in the full article. The article features an in-depth philosophical discussion about the added value of the various ways in which fitness landscapes are used in the social sciences. This discussion is absent in the current working paper. Th

The elementary events underlying force generation in neuronal lamellipodia

We have used optical tweezers to identify the elementary events underlying force generation in neuronal lamellipodia. When an optically trapped bead seals on the lamellipodium membrane, Brownian fluctuations decrease revealing the underlying elementary events. The distribution of bead velocities has long tails with frequent large positive and negative values associated to forward and backward jumps occurring in 0.1–0.2 ms with varying amplitudes up to 20 nm. Jump frequency and amplitude are reduced when actin turnover is slowed down by the addition of 25 nM Jasplakinolide. When myosin II is inhibited by the addition of 20 μM Blebbistatin, jump frequency is reduced but to a lesser extent than by Jasplainolide. These jumps constitute the elementary events underlying force generation

Age before beauty? Relationships between fertilization success and age-dependent ornaments in barn swallows

When males become more ornamented and reproduce more successfully as they grow older, phenotypic correlations between ornament exaggeration and reproductive success can be confounded with age effects in cross-sectional studies, and thus say relatively little about sexual selection on these traits. This is exemplified here in a correlative study of male fertilization success in a large colony of American barn swallows (Hirundo rustica erythrogaster). Previous studies of this species have indicated that two sexually dimorphic traits, tail length and ventral plumage coloration, are positively correlated with male fertilization success, and a mechanism of sexual selection by female choice has been invoked. However, these studies did not control for potential age-related variation in trait expression. Here, we show that male fertilization success was positively correlated with male tail length but not with plumage coloration. We also show that 1-year-old males had shorter tails and lower fertilization success than older males. This age effect accounted for much of the covariance between tail length and fertilization success. Still, there was a positive relationship between tail length and fertilization success among older males. But as this group consisted of males from different age classes, an age effect may be hidden in this relationship as well. Our data also revealed a longitudinal increase in both tail length and fertilization success for individual males. We argue that age-dependent ornament expression and reproductive performance in males complicate inferences about female preferences and sexual selection

The feasibility of introducing rapid diagnostic tests for malaria in drug shops in Uganda

BACKGROUND: National malaria control programmes and international agencies are keen to scale-up the use of effective rapid diagnostic tests (RDTs) for malaria. The high proportion of the Ugandan population seeking care at drug shops makes these outlets attractive as providers of malaria RDTs. However, there is no precedent for blood testing at drug shops and little is known about how such tests might be perceived and used. Understanding use of drug shops by communities in Uganda is essential to inform the design of interventions to introduce RDTs. METHODS: We conducted a qualitative study, with 10 community focus group discussions, and 18 in-depth interviews with drug shop attendants, health workers and district health officials. The formative study was carried out in Mukono district, central Uganda an area of high malaria endemicity from May-July 2009. RESULTS: Drug shops were perceived by the community as important in treating malaria and there was awareness among most drug sellers and the community that not all febrile illnesses were malaria. The idea of introducing RDTs for malaria diagnosis in drug shops was attractive to most respondents. It was anticipated that RDTs would improve access to effective treatment of malaria, offset high costs associated with poor treatment, and avoid irrational drug use. However, communities did express fear that drug shops would overprice RDTs, raising the overall treatment cost for malaria. Other fears included poor adherence to the RDT result, reuse of RDTs leading to infections and fear that RDTs would be used to test for human immune deficiency virus (HIV). All drug shops visited had no record on patient data and referral of cases to health units was noted to be poor. CONCLUSION: These results not only provide useful lessons for implementing the intervention study but have wide implications for scaling up malaria treatment in drug shops