The plausibility of a role for mercury in the etiology of autism : a cellular perspective

Autism is defined by a behavioral set of stereotypic and repetitious behavioral patterns in combination with social and communication deficits. There is emerging evidence supporting the hypothesis that autism may result from a combination of genetic susceptibility and exposure to environmental toxins at critical moments in development. Mercury (Hg) is recognized as a ubiquitous environmental neurotoxin and there is mounting evidence linking it to neurodevelopmental disorders, including autism. Of course, the evidence is not derived from experimental trials with humans but rather from methods focusing on biomarkers of Hg damage, measurements of Hg exposure, epidemiological data, and animal studies. For ethical reasons, controlled Hg exposure in humans will never be conducted. Therefore, to properly evaluate the Hg-autism etiological hypothesis, it is essential to first establish the biological plausibility of the hypothesis. This review examines the plausibility of Hg as the primary etiological agent driving the cellular mechanisms by which Hg-induced neurotoxicity may result in the physiological attributes of autism. Key areas of focus include: (1) route and cellular mechanisms of Hg exposure in autism; (2) current research and examples of possible genetic variables that are linked to both Hg sensitivity and autism; (3) the role Hg may play as an environmental toxin fueling the oxidative stress found in autism; (4) role of mitochondrial dysfunction; and (5) possible role of Hg in abnormal neuroexcitory and excitotoxity that may play a role in the immune dysregulation found in autism. Future research directions that would assist in addressing the gaps in our knowledge are proposed.

Characteristics of soy bread users and their beliefs about soy products

A two-stage random telephone/mail survey was conducted during the last quarter of 1998 among Adelaide residents to determine consumers' use of soy bread and other soy products and their health expectations of soy products. One in five (21%) of 1477 telephone subscribers usually consumed soy bread and related soy products. Comparisons of soy bread consumers and non-consumers, based on the mail survey sample, showed that more soy bread consumers used dietary supplements and ate low fat and vegetarian diets, though their experiences of ill health were similar. Soy bread consumers held stronger universalism (pro-nature) values than non-consumers. They also held more positive expectations about the benefits of soy consumption, including reductions in menstrual and menopausal symptoms, increased bowel regularity and reductions in the risk of heart disease and cancer. The findings are discussed in relation to the psychology of dietary supplementation, values orientations and physiological plausibility. Further investigations are suggested.

Alexander the Great, the dahlia, and the tortoise

Some of the problems of establishing the cause of the death of Alexander the Great are like the attempts to find causes other than hysteria for Anna O.'s symptoms. The more general problem of using plausibility as a criterion of the truth of such reconstructions are illustrated by the arguments embedded in Tom Stoppard's Arcadia.

The effect of events context on children's recall of non-experienced events across mutiple interviews

Purpose: The current study examined whether young children's willingness to assent to, and provide details about, a false (non-experienced) activity differs depending on whether the activity was allegedly embedded within (a) a specific event or (b) a broad (non-specified) time frame.
Method:  Ninety-nine children aged 4--5 years (from both low and high socioeconomic backgrounds) either (a) participated in a staged event that consisted of two activities or (b) did not participate in the staged event. One or two days later, all children were given false suggestions about a non-experienced (false) activity that had either high or low plausibility. Approximately 8, 15, and 22 days after the event, children were asked to recall the activities, and to answer a series of specific cued-recall questions.
Results: There was no effect of event context on assent rates, and the rate at which children reported interviewer suggestions. However, children who participated in the staged event provided fewer details about the false activity. Further, among those children who assented to the false activity, fewer subjects, objects, actions, temporal markers, locations, fantastic/improbable details, and confabulation errors were reported when the activity was embedded within the specific staged event.
Conclusion: The degree of error in children's accounts of a completely false activity is reduced when the activity is suggested to have occurred within a specified event as opposed to a broad (non-specified) time frame.

Dietary composition of pregnant women is related to size of the baby at birth

The fetal origins theory of adult disease suggests that term infants who are small for their gestational age have an increased susceptibility to chronic disease in adulthood as a consequence of physiologic adaptations to undernutrition during fetal life. Consistent evidence for an influence of women's dietary composition during pregnancy on growth of their babies is lacking, despite robust effects in animal experiments. We undertook a prospective observational study of 557 women aged 18-41 y, living in Adelaide, South Australia. Diet was assessed in early and late pregnancy using an FFQ. In early pregnancy, medians for energy intake, the proportion of energy derived from protein and from carbohydrate were 9.0 MJ, 17 and 48%, respectively. In late pregnancy the corresponding medians were 9.2 MJ, 16 and 49%. In early pregnancy, the percentage of energy derived from protein was positively associated with birth weight (P = 0.02) and placental weight (P = 0.07), independently of energy intake and weight gain during pregnancy, and after adjustment for potential confounders, including maternal age, parity, and smoking. Effects were stronger among women (n = 429) who had reliable data, based on prespecified criteria including the plausibility of dietary data when referenced against estimated energy expenditure. In addition, for this subgroup, the percentage of energy from carbohydrate in early and late pregnancy was negatively associated with ponderal index of the baby, and a specific effect of protein from dairy sources was identified. These data support the proposition that maternal dietary composition has an effect on fetal growth. Maternal diet in Western societies may therefore be important for the long-term health of the child.

Transnational citizenship: problems of definition, culture and democracy

There is widespread disagreement over whether transnational citizenship provides defensible extensions of, or meaningful complements to, national citizenship. A significant strand of criticism relies upon empirical arguments about political motivation and the consequences of transnationalism. This paper addresses two questions arising from empirical arguments relating to the nation state and democracy. Do the alleged cultural requirements for effective political action provide an insuperable barrier to transnational citizenship? Does transnational citizenship necessarily require a commitment to transnational democracy? I argue that these largely empirical criticisms do not succeed in casting doubt upon the normative plausibility or practical viability of transnational projects. On the first question, I point to a growing transnational political culture that serves to motivate transnational citizens. On the second question, I argue for a legitimate category of transnational citizenship that, although inspired by cosmopolitan morality, is different from it, and that does not require transnational democracy.

Ultraviolet vision in birds: what is its function?

Although UV vision was first demonstrated in birds in the early 1970s, its function is still unknown. Here we review the evidence for UV vision in birds, discuss the special properties of UV light, lay out in detail hypotheses for the function of UV vision in birds and discuss their plausibility. The main hypotheses are that UV vision functions: (i) in orientation, (ii) in foraging and (iii) in signalling. The first receives support from studies of homing pigeons, but it would be unwise to conclude that orientation is UV's primary function in all birds. It is especially important to test the signalling hypothesis because bird plumage often reflects UV and tests of theories of sexual selection have virtually always assumed that birds perceive plumage ''colours'' as humans do. A priori this assumption is unlikely to be correct, for unlike humans, birds see in the UV, have at least four types of cones and have a system of oil droplets which filters light entering individual cones.

Presbyterian ethos and environment in the novels of John Buchan : a religious and historical study

The aim of this thesis is to establish, from a historical and religious perspective, that the Presbyterian ethos and environment in which John Buchan was reared was the predominating influence in the writing of his novels. Presbyterianism was not the only influence on Buchan that determined the character of his stories. Buchan was by temperament a romantic, and this had considerable influence on his literature. His novels are romances, peopled by romantic figures who pursue romantic adventures. There are the signs of Buchan's romantic nature in the contents of the novels: creative imagination, sensitivity to nature, and expectations of the intrusion of other worlds, with destiny-determining events to follow. But Buchan had also an acquired classicism. His studies at Glasgow and Oxford Universities brought him in touch with a whole range of the master-pieces of classical literature, especially the works of Plato and Virgil. This discipline gave him clarity and conciseness in style, and balanced the romantic element in him, keeping his work within the bounds of reason. At the heart of Buchan's life and work, however, was his deeply religious nature and this, while influenced by romanticism and classicism, was the dominant force behind his work. Buchan did not accept in its entirety the Presbyterian doctrine conveyed to him by his father and his Church. He was moderate by temperament and shrank from excesses in religious matters, and, being a romantic, he shied away from any fixed creeds. He did embrace the fundamentals of Christianity, however, which he learned from his father and his Church, even if he did put aside the Rev. John's orthodox Calvinism. The basic Christianity which underlies all Buchan's novels has the stamp of Presbyterianism upon it, and that stamp is evident in his characters and their adventures. The expression of Christianity which Buchan embraced was the Christian Platonism of seventeenth century theologians, who taught and preached at Cambridge University, They gave prominence to the place of reason and conscience in man's search for God, They believed that reason and conscience were the ‘candle of the Lord’ which was existed every one. It was their conviction that, if that light was followed, it would lead men and women to God. They were against superstition and fanaticism in religion, against all forms of persecution for religious beliefs, and insisted that God could only be known by renouncing evil and setting oneself to live according to God’s will. This teaching Buchan received, but the stamp of his Presbyterianism was not obliterated. The basic doctrines which arose from his father's Presbyterianism and are to be found in Buchan's novels are as follows: a. the fear (or awe) of God, as life's basic religious attitude; b. the Providence of God as the ultimate determinative force in the outcome of events; c. the reality, malignity and universality of evil which must be forcefully and constantly resisted; d. the dignity of human beings in bearing God's image; e. the conviction that life has meaning and that its ultimate goal, therefore, is a spiritual one - as opposed to the accumulation of wealth, the achieving of recognition from society, and the gaining access to power; f. the necessity of challenge in life for growth and fulfilment, and the importance of fortitude in successfully meeting such challenge; g. the belief that, in the purpose of God, the weak confound the strong. These emphases of Presbyterianism are to be found in all Buchan's novels, to a greater or lesser degree. All his characters are serious people, with a moral purpose in life. Like the pilgrims of the Bible, they seek a country: true fulfilment. This quest becomes more spiritual and more dearly defined as Buchan grows in age and maturity. The progress is to be traced from his early novels, where fulfilment is sought in honour and self-approving competence, as advocated by classicism; to the novels of his middle years, where fulfilment is sought in adventures suggested by romanticism. In his final novel Sick Heart River. Buchan appears to have moved somewhat from his earlier classicism and his romanticism as the road to fulfilment. In this novel, Buchan expresses what, for him, is ultimate fulfilment: a conversion to God that produces self-sacrificing love for others. The terminally-ill Edward Leithen sets out on a romantic adventure that will enable him to die with dignity, and so, in classic style, justify his existence. He has a belief in God, but in a God who is almighty, distant and largely irrelevant to Leithen's life. In the frozen North of Canada, where he expects to find his meagre beliefs in God's absolute power confirmed by the icy majesty of mountain and plain, he finds instead God's mercy and it melts his heart. In a Christ-like way, he brings life to others through his death, believing that, through death, he will find life. There is sufficient evidence to give plausibility to the view that Buchan is describing in Leithen his own pilgrimage. If so, it means that Buchan found his way back to the fundamental experience of the Christian life, conversion, so strongly emphasised in his orthodox Presbyterianism home and Church. However, Buchan reaches this conclusion in a Christian Platonist way, through the natural world, rather than through the more orthodox pathway of Scripture.

Possible electrical double-layer contribution to the equilibrium thickness of intergranular Glass films in polycrystalline ceramics

The plausibility of the entropic repulsion of electrical double layers acting to stabilize an equilibrium thickness of intergranular glass films in polycrystalline ceramics is explored. Estimates of the screening length, surface potential, and surface charge required to provide a repulsive force sufficiently large to balance the attractive van der Waals and capillary forces for observable thicknesses of intergranular film are calculated and do not appear to be beyond possibility. However, it has yet to be established whether crystalline particles in a liquid-phase sintering medium possess an electrical double layer at high temperatures. If they do, such a surface charge layer may well have important consequences not only for liquid-phase sintering but also for high-frequency electrical properties and microwave sintering of ceramics containing a liquid phase.

Developing a presence in a mainstream market with a product perceived as offbeat

Generally when one thinks of Australian wine regions images of the Barossa Valley, the Hunter Valley or Margaret River may be conjured up as they have developed a presence in the mainstream market. Queensland, by contrast, may be perceived as offbeat, despite its similar quality and growing conditions. This study explores the plausibility of Queensland developing a presence in a mainstream market with findings from a survey completed by 347 people. The results indicate that when consumers choose their wine on the basis of terroir that personality, reputation and label design are the most important elements. Positioning wine from Queensland on its personality may hold the key to having an offbeat product compete in a mainstream market.

A new dempster-shafer theory-based method with fuzzy targets for fuzzy sets ranking

In this paper, a new Fuzzy Set (FS) ranking method (for type-1 and interval type-2 FSs), which is based on the Dempster-Shafer Theory (DST) of evidence with fuzzy targets, is investigated. Fuzzy targets are adopted to reflect human viewpoints on fuzzy ranking. Two important measures in DST, i.e., the belief and plausibility measures, are used to rank FSs. The proposed approach is evaluated with several benchmark examples. The use of the belief and plausibility measures in fuzzy ranking are discussed and compared. We further analyze the capability of the proposed approach in fulfilling six reasonable fuzzy ordering properties as discussed in [9]-[11].

A new online updating framework for constructing monotonicity-preserving fuzzy inference systems

In this paper, a new online updating framework for constructing monotonicity-preserving Fuzzy Inference Systems (FISs) is proposed. The framework encompasses an optimization-based Similarity Reasoning (SR) scheme and a new monotone fuzzy rule relabeling technique. A complete and monotonically-ordered fuzzy rule base is necessary to maintain the monotonicity property of an FIS model. The proposed framework attempts to allow a monotonicity-preserving FIS model to be constructed when the fuzzy rules are incomplete and not monotonically-ordered. An online feature is introduced to allow the FIS model to be updated from time to time. We further investigate three useful measures, i.e., the belief, plausibility, and evidential mass measures, which are inspired from the Dempster- Shafer theory of evidence, to analyze the proposed framework and to give an insight for the inferred outcomes from the FIS model.

Is low vitamin D status a risk factor for food allergy? Current evidence and future directions

Studies from several countries have reported an association between latitudes further from the equator and proxy markers of food allergy prevalence. As latitudes further from the equator are associated with lower sun exposure and vitamin D status (VDS), it has been proposed that low VDS may be a risk factor for food allergy. A range of basic science evidence supports the biological plausibility of this hypothesis; and recent work has identified a cross sectional association between low VDS and challenge proven food allergy in infants. Overall, however, the evidence regarding the relationship between VDS and food allergy remains controversial and the limited longitudinal data are discouraging. In this review we consider the evidence for and against low VDS as a risk factor for food allergy and discuss the possibility that other factors (including genetic variables) may contribute to the inconsistent nature of the available observational evidence. We then discuss whether genetic and/or environmental factors may modify the potential influence of VDS on food allergy risk. Finally, we argue that given the rising burden of food allergy, the balance of available evidence regarding the potential relevance of VDS to this phenomenon, and the inherent limitations of the existing observational data, there is a compelling case for conducting randomised clinical trials of vitamin D supplementation for the prevention of food allergy during early life.