In online social networks, the audience size commanded by an organization or an individual is a critical measure of that entity’s popularity and this measure has important economic and/or political implications. Such efforts to measure popularity of users or exploit knowledge about their audience are complicated by the presence of fake profiles on these networks. In this study, analysis of 62 million publicly available Twitter user profiles was conducted and a strategy to identify automatically generated fake profiles was established. Using (...) a combination of a pattern-matching algorithm on screen-names and an analysis of update times, a reasonable number of highly reliable fake user accounts were identified. Analysis of profile creation times and URLs of these fake accounts revealed their distinct behavior relative to a ground truth data set. The characteristics of friends and followers of users in the two data sets further revealed the very different nature of the two groups. The ratio of number of followers-to-friends for ground truth users was ∼1, consistent with past observations, while the fake profiles had a median ratio ∼30, indicating that the fake users we identified were primarily focused on gathering friends. An analysis of the temporal evolution of accounts over 2 years showed that the friends-to-followers ratio increased over time for fake profiles while they decreased for ground truth users. Our results, thus, suggest that a profile-based approach can be used for identifying a core set of fake online social network users in a time-efficient manner. (shrink)

It is argued that the characterization of the states of an infinite system of indistinguishable particles satisfying Bose-Einstein statistics which follows from the quantum-mechanical analog of de Finetti's theorem (2) can be used to interpret the nonuniqueness of the resolution into a convex combination of pure states of a quantum-mechanical mixed state.

Ship design needs to respond to and attract an ever more design conscious society. However, little research has been conducted into perceptions of beauty and pleasure and how such perceptions can be usefully absorbed into ship design. Aesthetic consideration, is seen as a distraction from the bespoke nature of the ship design process and is often avoided, second guessed or left for external consultancy. The ship design discipline requires the nurturing of its own aesthetic methods, for future development, and to (...) adapt some of the aesthetic ideals found in architecture, art and design. This paper argues that philosophy can be effective in interpreting what the passenger finds attractive and pleasurable. To illustrate the philosophical approach proposed, the `Elbe SWATH’ and the `Oasis of the Seas’ are investigated and compared using theoretical resources from the culturally focused philosophy of `Functional Beauty’. Conclusions suggest that the interpretation of the end users most valued appreciations can lead to design directives that deliver subjective qualities of beauty - beauty similar to those seen in the pure aims of the Elbe SWATH’s purposeful work craft, or comparable to nature’s beauty and purity in aim. (shrink)

We report the identification of a recurrent, 520-kb 16p12.1 microdeletion associated with childhood developmental delay. The microdeletion was detected in 20 of 11,873 cases compared with 2 of 8,540 controls and replicated in a second series of 22 of 9,254 cases compared with 6 of 6,299 controls. Most deletions were inherited, with carrier parents likely to manifest neuropsychiatric phenotypes compared to non-carrier parents. Probands were more likely to carry an additional large copy-number variant when compared to matched controls. The clinical (...) features of individuals with two mutations were distinct from and/or more severe than those of individuals carrying only the co-occurring mutation. Our data support a two-hit model in which the 16p12.1 microdeletion both predisposes to neuropsychiatric phenotypes as a single event and exacerbates neurodevelopmental phenotypes in association with other large deletions or duplications. Analysis of other microdeletions with variable expressivity indicates that this two-hit model might be more generally applicable to neuropsychiatric disease. © 2010 Nature America, Inc. All rights reserved. (shrink)

The rapid rise of international collaborative science has enabled access to genomic data. In this article, it is argued that to move beyond mapping genomic variation to understanding its role in complex disease aetiology and treatment will require extending data sharing for the purposes of clinical research translation and implementation.

BackgroundThe increased risk of developing attention-deficit hyperactivity disorder (ADHD) in extremely preterm infants is well-documented. Better understanding of perinatal risk factors, particularly those that are modifiable, can inform prevention efforts.MethodsWe examined data from the Extremely Low Gestational Age Newborns (ELGAN) Study. Participants were screened for ADHD at age 10 with the Child Symptom Inventory-4 (N = 734) and assessed at age 15 with a structured diagnostic interview (MINI-KID) to evaluate for the diagnosis of ADHD (N = 575). We studied associations (...) of pre-pregnancy maternal body mass index (BMI), pregestational and/or gestational diabetes, maternal smoking during pregnancy (MSDP), and hypertensive disorders of pregnancy (HDP) with 10-year and 15-year ADHD outcomes. Relative risks were calculated using Poisson regression models with robust error variance, adjusted for maternal age, maternal educational status, use of food stamps, public insurance status, marital status at birth, and family history of ADHD. We defined ADHD as a positive screen on the CSI-4 at age 10 and/or meeting DSM-5 criteria at age 15 on the MINI-KID. We evaluated the robustness of the associations to broadening or restricting the definition of ADHD. We limited the analysis to individuals with IQ ≥ 70 to decrease confounding by cognitive functioning. We evaluated interactions between maternal BMI and diabetes status. We assessed for mediation of risk increase by alterations in inflammatory or neurotrophic protein levels in the first week of life.ResultsElevated maternal BMI and maternal diabetes were each associated with a 55–65% increase in risk of ADHD, with evidence of both additive and multiplicative interactions between the two exposures. MSDP and HDP were not associated with the risk of ADHD outcomes. There was some evidence for association of ADHD outcomes with high levels of inflammatory proteins or moderate levels of neurotrophic proteins, but there was no evidence that these mediated the risk associated with maternal BMI or diabetes.ConclusionContrary to previous population-based studies, MSDP and HDP did not predict ADHD outcomes in this extremely preterm cohort, but elevated maternal pre-pregnancy BMI, maternal diabetes, and perinatal inflammatory markers were associated with increased risk of ADHD at age 10 and/or 15, with positive interaction between pre-pregnancy BMI and maternal diabetes. (shrink)

Kurt Gödel criticizes Rudolf Carnap's conventionalism on the grounds that it relies on an empiricist admissibility condition, which, if applied, runs afoul of his second incompleteness theorem. Thomas Ricketts and Michael Friedman respond to Gödel's critique by denying that Carnap is committed to Gödel's admissibility criterion; in effect, they are denying that Carnap is committed to any empirical constraint in the application of his principle of tolerance. I argue in response that Carnap is indeed committed to an empirical requirement vis‐à‐vis (...) tolerance, a fact that becomes clear upon closer scrutiny of Carnap's relevant writings. *Received July 2009; revised January 2010. †To contact the author, please write to: Department of Philosophy, University of Saskatchewan, 9 Campus Drive, Saskatoon, SK S7N 5A5, Canada; e‐mail: r.hudson@usask.ca. (shrink)

So a frenzied matron cries out to Phoebus as she rushes through an appalled Rome. In CQ 34 , 454f. I pointed out that the words primos in ortus could not here bear their normal sense ‘to the far east’ , which in view of the next line would be geographically absurd, and, distraught as the lady was, even so highly improbable. I did, however, then think R. J. Getty right in taking the expression primos ortus as simply = ‘the (...) east’, and adding ‘the epithet primos appears to be otiose’. But I now feel very doubtful about the epithet being viewed as otiose in order that the words may denote Egypt; quite different are the passages noted in OLD primus 6 ‘belonging to the rising sun, eastern’, as Stat. Silv. 1.4.73 ‘occidiias primasque domos’ in the cited Sen. Oed. 116 ‘miles… ausus Eois equitare campis / figere et mundo tua signa primo’ the literal meaning is no doubt ‘on the world's first edge’ , but its development into ‘eastern’ is readily seen. Egypt, however, as viewed by Rome, is but the bare beginning of the east, and that is what primos must indicate above : see OLD primus 10 b ‘the nearest part of, the entrance, threshold, or sim., of, noting e.g. Ov. Fast. 1.717 ‘horreat Aeneadas et primus et ultimus orbis’, Cic. Fam. 3.6.2. ‘te in prima prouincia uelle esse, ut quam primum decederes’. In a characteristic departure from their stock meaning Lucan's words primos in ortus must then mean ‘to the threshold of the east’, i.e. the delta of the Nile, as explained in the next line : contrast 7.360 primo gentes oriente = ‘the nations of the far east’ . For Egypt viewed as the beginning of the east, cf. Mela 1.9 ‘Asiae prima pars Aegyptus’, Plin. Nat. 5.47 ‘[Africae] adhaeret Asia, quam patere a Canopico ostio [Nili] ad Ponti ostium Timosthenes…tradidit’, Mart. Cap. 6.675 ‘Aegyptus… Asiae caput, 3 quae una ab ostio Canopi ad ostium Ponti habet… milia passuum’; cf. the close association of Egypt with the east in Virg. Aen. 8.687 ‘Aegyptum uiresque Orientis’. For the varied use of the word primus should be noted too Luc. 9.413f. ‘nee… plus litora Nili / quam Scythicus Tanais primis a Gadibus absunt’, ‘from Gades in the far west’ , ‘Gades the first place in the west’ , i.e. the threshold of the Mediterranean. (shrink)

The text of each passage commented on is that of Housman except where otherwise stated. The following editions of Lucan or other works concerned with him are indicated by the scholar's name only: Text: A. E. Housman . Text with commentary: F. Oudendorp ; P. Burman ; C. H. Weise ; C. E. Haskins ; R. J. Getty, Book 1.

The text quoted above each note is that of the edition of Seneca's tragedies by Otto Zwierlein , OCT 1986; numerous passages are discussed in his Kritischer Kommentar zu den Tragüdien Senecas , Stuttgart, 1986; various textual suggestions were made in a correspondence with Zw. by B. Axelson . Other works on Seneca's tragedies, referred to by the scholar's name only, are: Text and translation: F. J. Miller, Loeb, 1917; L. Herrmann, Budé, 1924–6. Text with commentary: R. J. Tarrant, Agamemnon (...) , and Thyestes ; J. G. Fitch, Hercules Furens . Text with commentary and translation: Elaine Fantham, Troades ; A. J.Boyle, Phaedra. (shrink)