On the Complexity of Strong and Epistemic Credal Networks

Credal networks are graph-based statistical models whose parameters take values on a set, instead of being sharply specified as in traditional statistical models (e.g., Bayesian networks). The result of inferences with such models depends on the irrelevance/independence concept adopted. In this paper, we study the computational complexity of inferences under the concepts of epistemic irrelevance and strong independence. We strengthen complexity results by showing that inferences with strong independence are NP-hard even in credal trees with ternary variables, which indicates that tractable algorithms, including the existing one for epistemic trees, cannot be used for strong independence. We prove that the polynomial time of inferences in credal trees under epistemic irrelevance is not likely to extend to more general models, because the problem becomes NP-hard even in simple polytrees. These results draw a definite line between networks with efficient inferences and those where inferences are hard, and close several open questions regarding the computational complexity of such models.

Synthesis of visible-light-activated yellow amorphous TiO2 photocatalyst

Visible-light-activated yellow amorphous TiO₂ (yam- TiO ₂) was synthesised by a simple and organic-free precipitation method. TiN, an alternative precursor for TiO₂ preparation, was dissolved in hydrogen peroxide under acidic condition (pH∼1) adjusted by nitric acid. The yellow precipitate was obtained after adjusting pH of the resultant red brown solution to 2 with NH₄OH. The BET surface area of this sample was 261 m²/g. The visible light photoactivity was evaluated on the basis of the photobleaching of methylene blue (MB) in an aqueous solution by using a 250 W metal halide bulb equipped with UV cutoff filter (λ>420 nm) under aerobic conditions. Yam- TiO₂ exhibits an interesting property of being both surface adsorbent and photoactive under visible light. It was assigned to the η²-peroxide, an active intermediate form of the addition of H₂O₂ into crystallined TiO₂ photocatalyst. It can be concluded that an active intermediate form of titanium peroxo species in photocatalytic process can be synthesised and used as a visible-light-driven photocatalyst

Sins of the Flesh: Zola, Naturalism and the Madeleine Redemption Narrative in Nineteenth-Century France

Mary Magdalene has endured over the centuries as a powerful icon for the redemption of the so-called sins of the flesh. In arguing that her appeal to writers was experienced no more keenly than in nineteenth-century France, this article reflects on the political, ideological and gender assumptions that are woven into the Madeleine narrative of redemption. It goes on to propose that, with the rise of the naturalist novel, relying on pseudo-scientific theories of pre-determination, the Madeleine myth is radically rewritten in Zola’s Madeleine Férat, an often neglected novel in which the Calvinist doctrine of original sin and predestination not only challenges the very notion of redemption from sexual waywardness, but inflects some of the defining principles of naturalism.

Ecological dynamics of extinct species in empty habitat networks. 2. The role of host plant dynamics

This paper explores the relative effects of host plant dynamics and butterfly-related parameters on butterfly persistence. It considers an empty habitat network where a rare butterfly (Cupido minimus) became extinct in 1939 in part of its historical range in north Wales, UK. Surviving populations of the butterfly in southern Britain were visited to assess use of its host plant (Anthyllis vulneraria) in order to calibrate habitat suitability and carrying capacity in the empty network in north Wales. These data were used to deduce that only a portion ( similar to 19%) of the host plant network from north Wales was likely to be highly suitable for oviposition. Nonetheless, roughly 65,460 eggs (3273 adult equivalents) could be expected to be laid in north Wales, were the empty network to be populated at the same levels as observed on comparable plants in surviving populations elsewhere. Simulated metapopulations of C. minimus in the empty network revealed that time to extinction and patch occupancy were significantly influenced by carrying capacity, butterfly mean dispersal distance and environmental stochasticity, although for most reasonable parameter values, the model system persisted. Simulation outputs differed greatly when host plant dynamics was incorporated into the modelled butterfly dynamics. Cupido minimus usually went extinct when host plant were at low densities. In these simulations host plant dynamics appeared to be the most important determinant of the butterfly's regional extirpation. Modelling the outcome of a reintroduction programme to C. minimus variation at high quality locations, revealed that 65% of systems survived at least 100 years. Given the current amount of resources of the north Wales landscape, the persistence of C. minimus under a realistic reintroduction programme has a good chance of being successful, if carried out in conjunction with a host plant management programme.

“How Can a Woman Who Has Been Raped Be Believed?”: Andrea Dworkin, Sexual Violence and the Ethics of Belief

In June 2000, Andrea Dworkin, an American feminist activist and author, published an account of being raped in a Paris hotel room a year earlier. The story was met with widespread disbelief, including from feminist readers. This article explores the reasons for this disbelief, asking how and why narratives of rape are granted – or denied – truth status by their readers. The article argues for understanding the conferral of belief as a narrative transaction involving the actions of both narrator and reader. It posits that Dworkin was widely seen as an unreliable narrator but argues that for ideologically charged narratives such as rape narratives judgements of reliability and belief inevitably draw upon the normative standpoint of the reader. I suggest that there are opposing criteria for establishing the truth of rape narratives; a ‘factual’ or legal model, which sees rape narratives as requiring scrutiny, and an ‘experiential’ model, located within certain strands of feminist politics, which emphasises the ethical importance of believing women’s narratives. The article finishes with a consideration of the place of belief within an ethics of reading and reception of rape narratives.

Immune modulation in advanced radiotherapies: Targeting out-of-field effects

By virtue of being a localized treatment modality, radiotherapy is unable to deliver a tumoricidal radiation dose to tissues outside of the irradiated field. Nevertheless, ionizing radiation may result in radiation damage mediated by a bystander like effect away from the irradiated field, but this response is likely to be modest when radiotherapy is the sole treatment modality. Over the last decade there has been a re-emergence of immune modulating therapies as anti-cancer treatment modalities. Clinical trials on vaccines have on the whole been largely disappointing, but greater response rates have been observed from the immune checkpoint modulators. A clinical benefit of using such agents has been shown in disease sites such as melanoma and non-small cell lung cancer. There is growing pre-clinical data and a number of case reports which suggest the presence of abscopal effects when radiotherapy is co-administered with immune checkpoint inhibitors, suggesting that this combination may lead to an enhanced tumour response outside of the primary treatment field. In this review, the mechanisms of such an enhanced out-of-field tumour response, the potential clinical utilities, the optimal radiotherapy delivery and considerations for clinical follow-up following treatment are discussed.

Trends and Determinants of Work-Retirement Transitions under Changing Institutional Conditions: Germany, England and Japan compared

Many governments world-wide are promoting longer working life due to the social and economic repercussions of demographic change. However, not all workers are equally able to extend their employment careers. Thus, while national policies raise the overall level of labour market participation, they might create new social and labour market inequalities. This paper explores how institutional differences in the United Kingdom, Germany and Japan affect individual retirement decisions on the aggregate level, and variations in individuals’ degree of choice within and across countries. We investigate which groups of workers are disproportionately at risk of being ‘pushed’ out of employment, and how such inequalities have changed over time. We use comparable national longitudinal survey datasets focusing on the older population in England, Germany and Japan. Results point to cross-national differences in retirement transitions. Retirement transitions in Germany have occurred at an earlier age than in England and Japan. In Japan, the incidence of involuntary retirement is the lowest, reflecting an institutional context prescribing that employers provide employment until pension age, while Germany and England display substantial proportions of involuntary exits triggered by organisational-level redundancies, persistent early retirement plans or individual ill-health.

Turing’s Menagerie: Talking Lions, Virtual Bats, Electric Sheep and Analogical Peacocks: Common Ground and Common Interest are Necessary Components of Engagement

This theoretical paper attempts to define some of the key components and challenges required to create embodied conversational agents that can be genuinely interesting conversational partners. Wittgenstein’s argument concerning talking lions emphasizes the importance of having a shared common ground as a basis for conversational interactions. Virtual bats suggests that–for some people at least–it is important that there be a feeling of authenticity concerning a subjectively experiencing entity that can convey what it is like to be that entity. Electric sheep reminds us of the importance of empathy in human conversational interaction and that we should provide a full communicative repertoire of both verbal and non-verbal components if we are to create genuinely engaging interactions. Also we may be making the task more difficult rather than easy if we leave out non-verbal aspects of communication. Finally, analogical peacocks highlights the importance of between minds alignment and establishes a longer term goal of being interesting, creative, and humorous if an embodied conversational is to be truly an engaging conversational partner. Some potential directions and solutions to addressing these issues are suggested.

Increasing the TRL of an L band Retrodirective array for Type Approved SATCOM applications

Retrodirective, self-steering, antennas have the advantage of being able to automatically return a signal back in the direction along from which it originated. The tracking is real time and is carried out in the analogue domain which results in simple circuits which can be accommodated, planar-form, behind the antenna elements. The main objective of this paper is to detail the continuation of the work on L band retrodirective antennas which has the ambition of increasing the TRL such that a minimal viable product can be produced, suitable for type approval as an L band SATCOM user terminal. The focus will be the technical challenges that have arisen as the retrodirective antenna is moved up the TRL chain. Some of these aspects include the ability to track very weak modulated signals (S/N tending to 0dB), TX/RX filter and duplexer specifications, PA and LNA considerations. The resultant retrodirective architecture will be compared against typical specifications of L band satellite ground terminals, showing that the retrodirective antenna offers a simple and effective real time tracking antenna architecture.

‘The Problem of the Future in Nineteenth-Century Spain’

This article examines the problems and paradoxes in the representation of the future in three nineteenth-century Spanish works: El futuro Madrid (1868) by Fernández de los Ríos, ‘Madrid en el siglo xxi’ (1847) by Neira de Mosquera, and Ni en la vida ni en la muerte by Juan Bautista Amorós (Silverio Lanza). While these texts demonstrate Spain’s participation in the general movement towards using the future as a setting for literary works, they do not corroborate the theory that the nineteenth century was a time of optimism and belief in the doctrine of Progress. Concepts derived from discussions of the future in the history of ideas, such as historia magistra vitae, are shown to be relevant to discussion of these futuristic fictions, in sometimes unexpected ways.

Use of eye care services among diabetic patients in urban and rural China.

OBJECTIVE: To assess the use of eye care and its predictors among diabetic patients in China. DESIGN: Cross-sectional, clinic-based study. PARTICIPANTS: Diabetic patients 18 years of age or older were recruited consecutively from an urban tertiary and community hospitals and from a rural clinic in Guangdong, China. METHODS: Information obtained by questionnaire and chart review included: demographic and socioeconomic status, knowledge about diabetic retinopathy (DR), and ocular and medical history. MAIN OUTCOME MEASURES: Self-reported or chart history of an eye examination ever or within the preceding 12 months. RESULTS: The participation rate among 889 eligible subjects was 92.7%. Among 824 participants (mean age, 62.6+/-12.9 years; 58.8% female), 550 (66.7%) had not been examined in the last year as recommended by the American Academy of Ophthalmology, and 356 (43.2%) had never been examined. For the rural hospital, these figures were 81.1% and 68.7%, respectively. In regression analyses, factors associated with having an eye examination in the last year were: attendance at urban hospitals (odds ratio [OR], 3.46 [P<0.001] and 1.76 [P = 0.021] for the tertiary and community hospitals, respectively, compared with the rural clinic), higher DR knowledge score (OR, 1.24; P = 0.001), greater concern about vision loss (OR, 1.22; P = 0.007), and recommendation of regular eye examinations by the provider (OR, 2.36; P = 0.011). Predictors of ever having an eye examination were similar. Monthly income and health insurance status were not predictive of being examined. CONCLUSIONS: These results suggest that the low proportion of diabetic receiving recommended annual eye examinations in China may be improved through patient and physician education. Copyright © 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Contracts for the Sale of Land: Understanding the Impecuniosity Defence

Where either the seller or buyer of landed property fails to complete a contract to sell land the non-breaching party has a right to seek specific performance of the contract. This remedy would compel the party in default to perform the contract on pain of being held in contempt of court if the court's order is not obeyed. The defaulting party would not be able to satisfy its obligations under the law by paying a sum of money as damages for breach of contract. This paper considers the impecuniosity defence to specific performance as recognised by courts in Northern Ireland, the Republic of Ireland, Australia and New Zealand. Where the buyer demonstrates that he or she simply cannot raise the funds to buy the property specific performance will not be decreed and the court will make an award of damages for breach of contract measured by the difference between the contract price and the market price of the property at the time of default. The paper considers the nature and parameters of this defence and how it differs (if at all) from the alternative defence of extreme hardship. The paper addresses the question of whether it might be better to move to a position where sellers of land in all cases no longer enjoy a presumption of specific performance but have to demonstrate that the alternative remedy of damages is clearly inadequate. If this should be so the paper goes on to consider whether abolition of the presumption in favour of specific performance for sellers should lead to abolition of the presumption of specific performance for buyers, as is the position in Canada following the Supreme Court's decision in Semelhago v Paramadevan [1996] 2 SCR 415.