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We agree that combining rational analysis with cognitive bounds, what we previously introduced as Cognitively Bounded Rational Analysis, is a promising and under-used methodology in psychology. We further situate the framework in the literature, and highlight the important issue of a theory of subjective utility, which is not addressed sufficiently clearly in the framework or related previous work.
Angiostrongylus cantonensis is a pathogenic nematode and the cause of neuroangiostrongyliasis, an eosinophilic meningitis more commonly known as rat lungworm disease. Transmission is thought to be primarily due to ingestion of infective third stage larvae (L3) in gastropods, on produce, or in contaminated water. The gold standard to determine the effects of physical and chemical treatments on the infectivity of A. cantonensis L3 larvae is to infect rodents with treated L3 larvae and monitor for infection, but animal studies are laborious and expensive and also raise ethical concerns. This study demonstrates propidium iodide (PI) to be a reliable marker of parasite death and loss of infective potential without adversely affecting the development and future reproduction of live A. cantonensis larvae. PI staining allows evaluation of the efficacy of test substances in vitro, an improvement upon the use of lack of motility as an indicator of death. Some potential applications of this assay include determining the effectiveness of various anthelmintics, vegetable washes, electromagnetic radiation and other treatments intended to kill larvae in the prevention and treatment of neuroangiostrongyliasis.
Children of parents with mood and psychotic disorders are at elevated risk for a range of behavioral and emotional problems. However, as the usual reporter of psychopathology in children is the parent, reports of early problems in children of parents with mood and psychotic disorders may be biased by the parents' own experience of mental illness and their mental state.
Independent observers rated psychopathology using the Test Observation Form in 378 children and youth between the ages of 4 and 24 (mean = 11.01, s.d. = 4.40) who had a parent with major depressive disorder, bipolar disorder, schizophrenia, or no history of mood and psychotic disorders.
Observed attentional problems were elevated in offspring of parents with major depressive disorder, bipolar disorder and schizophrenia (effect sizes ranging between 0.31 and 0.56). Oppositional behavior and language/thought problems showed variable degrees of elevation (effect sizes 0.17 to 0.57) across the three high-risk groups, with the greatest difficulties observed in offspring of parents with bipolar disorder. Observed anxiety was increased in offspring of parents with major depressive disorder and bipolar disorder (effect sizes 0.19 and 0.25 respectively) but not in offspring of parents with schizophrenia.
Our results suggest that externalizing problems and cognitive and language difficulties may represent a general manifestation of familial risk for mood and psychotic disorders, while anxiety may be a specific marker of liability for mood disorders. Observer assessment may improve early identification of risk and selection of youth who may benefit from targeted prevention.
The properties of the acoustic modes are sensitive to magnetic activity. The unprecedented long-term Kepler photometry, thus, allows stellar magnetic cycles to be studied through asteroseismology. We search for signatures of magnetic cycles in the seismic data of Kepler solar-type stars. We find evidence for periodic variations in the acoustic properties of about half of the 87 analysed stars. In these proceedings, we highlight the results obtained for two such stars, namely KIC 8006161 and KIC 5184732.
In space and astrophysical plasmas, violent events or instabilities inject energy into turbulent motions at large scales. Nonlinear interactions among the turbulent fluctuations drive a cascade of energy to small perpendicular scales at which the energy is ultimately converted into plasma heat. Previous work with the incompressible magnetohydrodynamic (MHD) equations has shown that this turbulent energy cascade is driven by the nonlinear interaction between counterpropagating Alfvén waves – also known as Alfvén wave collisions. Direct numerical simulations of weakly collisional plasma turbulence enables deeper insight into the nature of the nonlinear interactions underlying the turbulent cascade of energy. In this paper, we directly compare four cases: both periodic and localized Alfvén wave collisions in the weakly and strongly nonlinear limits. Our results reveal that in the more realistic case of localized Alfvén wave collisions (rather than the periodic case), all nonlinearly generated fluctuations are Alfvén waves, which mediates nonlinear energy transfer to smaller perpendicular scales.
In space and astrophysical plasmas, turbulence is responsible for transferring energy from large scales driven by violent events or instabilities, to smaller scales where turbulent energy is ultimately converted into plasma heat by dissipative mechanisms. The nonlinear interaction between counterpropagating Alfvén waves, denoted Alfvén wave collisions, drives this turbulent energy cascade, as recognized by early work with incompressible magnetohydrodynamic (MHD) equations. Recent work employing analytical calculations and nonlinear gyrokinetic simulations of Alfvén wave collisions in an idealized periodic initial state have demonstrated the key properties that strong Alfvén wave collisions mediate effectively the transfer of energy to smaller perpendicular scales and self-consistently generate current sheets. For the more realistic case of the collision between two initially separated Alfvén wavepackets, we use a nonlinear gyrokinetic simulation to show here that these key properties persist: strong Alfvén wavepacket collisions indeed facilitate the perpendicular cascade of energy and give rise to current sheets. Furthermore, the evolution shows that nonlinear interactions occur only while the wavepackets overlap, followed by a clean separation of the wavepackets with straight uniform magnetic fields and the cessation of nonlinear evolution in between collisions, even in the gyrokinetic simulation presented here which resolves dispersive and kinetic effects beyond the reach of the MHD theory.
We argue that a radically increased emphasis on (bounded) optimality can contribute to cognitive science by supporting prediction. Bounded optimality (computational rationality), an idea that borrowed from artificial intelligence, supports a priori behavioral prediction from constrained generative models of cognition. Bounded optimality thereby addresses serious failings with the logic and testing of descriptive models of perception and action.
Although Zwaan et al. (2018) have made a compelling case as to why direct replications should occur more frequently than they do, they do not address how such replications attempts can best be encouraged. We propose a novel method for incentivising replication attempts and discuss some issues surrounding its implementation.
Avian malaria, caused by Plasmodium spp., is an emerging disease in New Zealand (NZ). To detect Plasmodium spp. infection and quantify parasite load in NZ birds, a real-time polymerase chain reaction (PCR) (qPCR) protocol was used and compared with a nested PCR (nPCR) assay. A total of 202 blood samples from 14 bird species with known nPCR results were tested. The qPCR prevalences for introduced, native and endemic species groups were 70, 11 and 21%, respectively, with a sensitivity and specificity of 96·7 and 98%, respectively, for the qPCR, while a sensitivity and specificity of 80·9 and 85·4% were determined for the nPCR. The qPCR appeared to be more sensitive in detecting lower levels of parasitaemia. The mean parasite load was significantly higher in introduced bird species (2245 parasites per 10 000 erythrocytes) compared with endemic species (31·5 parasites per 10 000 erythrocytes). In NZ robins (Petroica longipes), a significantly lower packed cell volume was found in birds that were positive for Plasmodium spp. compared with birds that were negative. Our data suggest that introduced bird species, such as blackbirds (Turdus merula), have a higher tolerance for circulating parasite stages of Plasmodium spp., indicating that introduced species are an important reservoir of avian malaria due to a high infection prevalence and parasite load.
The four main findings about the age and abundance structure of the Milky Way bulge based on microlensed dwarf and subgiant stars are: (1) a wide metallicity distribution with distinct peaks at [Fe/H] = -1.09, -0.63, -0.20, +0.12, +0.41; (2) a high fraction of intermediate-age to young stars where at [Fe/H] > 0 more than 35 % are younger than 8 Gyr, (3) several episodes of significant star formation in the bulge 3, 6, 8, and 11 Gyr ago; (4) the ‘knee’ in the α-element abundance trends of the sub-solar metallicity bulge appears to be located at a slightly higher [Fe/H] (about 0.05 to 0.1 dex) than in the local thick disk.
In this commentary, we present two examples where perception is not only influenced by, but also in fact driven by, top-down effects: hallucinations and mental imagery. Crucially, both examples avoid all six of the potential confounds that Firestone & Scholl (F&S) raised as arguments against previous studies claiming to demonstrate the influence of top-down effects on perception.
Basic Self disturbances (BSD), including changes of the 'pre-reflexive' sense of self and the loss first-person perspective, are characteristic of the schizophrenic spectrum disorders and highly prevalent in subjects at 'ultra high risk' for psychosis (UHR). The current literature indicates that cortical midline structures (CMS) may be implicated in the neurobiological substrates of the 'basic self' in healthy controls.
Neuroanatomical investigation of BSD in a UHR sample
To test the hypotheses :(i) UHR subjects have higher 'Examination of Anomalous Self Experience, EASE' scores as compared to controls, (ii) UHR subjects have neuroanatomical alterations as compared to controls in CMS, (iii) within UHR subjects, EASE scores are directly related to structural CMS alterations.
32 HR subjects (27 antipsychotics-naïve) and 17 healthy controls (HC) were assessed with the 57-items semi-structured EASE interview. Voxel-Based Morphometry (VBM) was conducted in the same subjects, with a-priori Region of Interests (ROIs) defined in the CMS (anterior/posterior cingulate and medial-prefrontal cortex).
Despite high variability in the HR group, the overall EASE score was higher (t-test >0.01, Cohen's d =2.91) in HR (mean=30.15, SD=16.46) as compared to HC group (mean=1.79, SD=2.83). UHR subjects had gray matter reduction in CMS as compared to HC (p>0.05 FWE-corrected). Across the whole sample, lower gray matter volume in the anterior cingulate was correlated with higher EASE scores (p>0.05).
This study provides preliminary evidence that gray matter reductions in the CMS are correlated with BSD in UHR people.
Cannabis use is associated with an increased risk of developing a psychotic disorder but the temporal relationship between cannabis use and onset of illness is unclear. The objective of this study was to assess prospectively the influence of cannabis use on transition to psychosis in people at ultra-high risk (UHR) for the disorder.
Lifetime and continued cannabis use was assessed in a consecutively ascertained sample of 182 people (104 male, 78 female) at UHR for psychosis. Individuals were then followed clinically for 2 years to determine their clinical outcomes.
Lifetime cannabis use was reported by 134 individuals (73.6%). However, most of these individuals had stopped using cannabis before clinical presentation (n = 98, 73.1%), usually because of adverse effects. Among lifetime users, frequent use, early-onset use and continued use after presentation were all associated with an increase in transition to psychosis. Transition to psychosis was highest among those who started using cannabis before the age of 15 years and went on to use frequently (frequent early-onset use: 25%; infrequent or late-onset use: 5%; χ21 = 10.971, p = 0.001). However, within the whole sample, cannabis users were no more likely to develop psychosis than those who had never used cannabis (cannabis use: 12.7%; no use: 18.8%; χ21 = 1.061, p = 0.303).
In people at UHR for psychosis, lifetime cannabis use was common but not related to outcome. Among cannabis users, frequent use, early-onset use and continued use after clinical presentation were associated with transition to psychosis.
Hagiography is by definition about measuring the distance between the human and the sacred: the saint's own distance, but also the hagiographer's and ours. Reginald of Durham's late-twelfth-century life of Godric of Finchale, begun during the saint's lifetime and finished not long after his death, probes all sorts of distances. It is no accident that many of Godric's feats and miracles involve clairvoyance and its auditory equivalent: feats of overcoming spatial or temporal distances in one's seeing and one's hearing. The Vita has a precise sense of place, centered on Godric's cell in the forest, but within a concentric circle of larger and larger horizons: the region, the territory of Durham, the sea shore, the ocean, Jerusalem; for Godric was a seafaring merchant before he became a hermit, and also a Jerusalem pilgrim who lived in the Holy Land for several years.
There is not very much scholarly literature on Godric, but interest in him has been constant. There is even a modern novel about him. Historians have long recognized the Vita's value as testimony to many aspects of medieval culture that are rarely illuminated by the narrative sources of the period. It is a life of a man of the people. Pirenne drew attention to Godric's early life as a merchant, as an international trader, and as a man of relatively humble origins working his way up by engaging in trade. Tom Licence and Susan Ridyard have studied him as a lay religious figure, integrated – or perhaps coopted or even coerced – by the monks of Durham into their project of possessing, controlling, and shaping their surrounding territory both economically and spiritually. The monks gained in him a hermitage, a cell with adjacent lands – but they also acquired a revered lay saint who could help their outreach to the laity of the region by modeling a spiritual life appropriate to them. Michael Clanchy has discussed Godric as an interesting example of a layman living on the periphery of monastic and literate culture.
Violent disorder broke out in various parts of England during the political turmoil of 1326–7 and included particularly severe rioting in the monastic towns of Abingdon, St Albans, and Bury St Edmunds in Suffolk. In January 1327 agitators from London roused the townspeople at Bury to conspire to attack and destroy the abbey of St Edmund. An armed mob forced entrance through the gates of the abbey on 14 January and seized and imprisoned the officials of the convent and several monks. They carried away all the treasures of the abbey, including the charters, muniments, and papal bulls from the sacristy and the treasury. Accounts of the legal process that followed the riots show the magnitude of the abbey's losses: in one, the monks alleged that the rioters had carried off three copies of a charter of King Cnut in their favour and four copies of a charter in Harthacnut's name. So denuded were the archives that the abbot had to pay the king to stay a suit against him in the royal courts, since he claimed the deeds he would have used for the defence of his case had been stolen by the rioters.
Rebels targeted Bury's archives again during the Peasants' Revolt in 1381. This time, however, they sought not to destroy the deeds but rather to consult them for evidence to substantiate some of their own claims. Like the authors of cahiers de doléance produced by the third estate in France in 1789, the rebels believed that the burdens of taxation and obligation had fallen less heavily on earlier generations, and that the abbey’s earliest charters would confirm their view. They thus demanded that the monks produce, ‘in the sight of the commons’, the charters of liberty for ‘the vill which Cnut, the founder of the monastery had once granted’. The monks duly brought out before the guildhall all the charters they could find and showed them to the mayor, the aldermen, ‘and a whole crowd of villeins’. When the rebels declared themselves unhappy with the documents produced by the abbey, the monks agreed to search their charters again to find the evidence for the liberties which St Edmund’s claimed; further, they promised that if they found none, they would produce new ones to serve the purpose.
Contained in two manuscripts preserved in the Biblioteca Apostolica Vaticana is a little-known chronicle by an anonymous writer of the mid-twelfth century which may shed more light on an epoch-making event on the eve of the Crusades: the Norman conquest of Sicily. This source, collated into a single transcription by Giambattista Caruso in 1723 and reproduced in the Rerum Italicarum Scriptores by Ludovico Muratori in 1726, is called the Historia Sicula a Normannis ad Petrum Aragonensem by Anonymus Vaticanus. Despite the fact that it is one of a very few sources to describe a seminal episode in Mediterranean history, the Historia Sicula has not been discussed in any depth for over a century. This essay seeks to correct that oversight.
In his formative work, Mohammed and Charlemagne, the great Belgian historian Henri Pirenne contended that ‘the rapid and unexpected advance of Islam’ had precipitated ‘the end of Mediterranean unity’ by vanquishing the mare nostrum of ancient Rome. The resultant loss of Sicily to the Aghlabids of North Africa in the ninth century established what maritime historian A.R. Lewis termed ‘the Islamic Imperium’ and inspired the fourteenth-century Arab scholar Ibn Khaldūn to claim that ‘the Muslims had gained control over the whole of the Mediterranean’. At the beginning of the eleventh century, the Mediterranean was, in effect, a Muslim lake with most of its major islands, including Sicily, firmly ensconced in Dar al-Islam (the ‘House of Islam’).
A string of recent publications has sought to emphasize the relationship between the memorial and the material in the medieval period. Drawing on this body of work, this essay explores the dynamic relationship between physical objects and the memories associated with them in the Historia ecclesiastica of Orderic Vitalis. Written between c. 1114 and 1141 at the abbey of St Evroul, located in the pays d'Ouche on the southern frontier of Normandy, the massive thirteen-book Historia is widely recognized by scholars as being one of the most important sources for the history of the Anglo-Norman world and beyond, and it has been the subject of much study since the 1950s. Whilst it is a well known fact that Orderic drew on a large number of written and oral sources in the writing of the Historia, the exact role played by the material and the visual in this process has remained largely unexplored. The focus of this article is thus on the way in which these objects are described in Orderic's narrative and the implications of this for our understanding of the Historia as a whole.
Leonie Hicks has recently highlighted ‘the visibility of the past’ as an important theme in historical writing, observing that for the Anglo-Norman chroniclers, ‘monuments and places … were much more than just illustrations to or diversions from the main narrative: they were in fact integral to the message they were trying to convey'. Thus, while such descriptive passages are interesting in and of themselves, the purpose of examining this largely unexplored aspect of Orderic’s magnum opus here is to highlight the textual richness of the Historia and to demonstrate what these passages reveal about the purpose of its narrative. For the more one studies Orderic, the more one notices passages concerning objects that he claimed were still in existence at the time of his writing, such as a memorial roll, a Psalter, and a stone arch.