What makes you not a Sikh? : a preliminary mapping of values

This study sets out to establish which Sikh values contrasted with or were shared by non-Sikh adolescents. A survey of attitude toward a variety of Sikh values was fielded in a sample of 364 non-Sikh schoolchildren aged between 13 and 15 in London. Values where attitudes were least positive concerned Sikh duties/code of conduct, festivals, rituals, prayer Gurdwara attendance, listening to scripture recitation, the amrit initiation. Sikh values empathized with by non-Sikhs concerned family pride, charity, easy access to ordination and Gurdwaras, maintaining the five Ks, seeing God in all things, abstaining from meat and alcohol and belief in the stories of Guru Nanak. Further significant differences of attitude toward Sikhism were found in comparisons by sex, age and religious affiliation. Findings are applied to teaching Sikhism to pupils of no faith adherence. The study recommends the extension of values mapping to specifically Sikh populations

Logopenic and nonfluent variants of primary progressive aphasia are differentiated by acoustic measures of speech production

Differentiation of logopenic (lvPPA) and nonfluent/agrammatic (nfvPPA) variants of Primary Progressive Aphasia is important yet remains challenging since it hinges on expert based evaluation of speech and language production. In this study acoustic measures of speech in conjunction with voxel-based morphometry were used to determine the success of the measures as an adjunct to diagnosis and to explore the neural basis of apraxia of speech in nfvPPA. Forty-one patients (21 lvPPA, 20 nfvPPA) were recruited from a consecutive sample with suspected frontotemporal dementia. Patients were diagnosed using the current gold-standard of expert perceptual judgment, based on presence/absence of particular speech features during speaking tasks. Seventeen healthy age-matched adults served as controls. MRI scans were available for 11 control and 37 PPA cases; 23 of the PPA cases underwent amyloid ligand PET imaging. Measures, corresponding to perceptual features of apraxia of speech, were periods of silence during reading and relative vowel duration and intensity in polysyllable word repetition. Discriminant function analyses revealed that a measure of relative vowel duration differentiated nfvPPA cases from both control and lvPPA cases (r2 = 0.47) with 88% agreement with expert judgment of presence of apraxia of speech in nfvPPA cases. VBM analysis showed that relative vowel duration covaried with grey matter intensity in areas critical for speech motor planning and programming: precentral gyrus, supplementary motor area and inferior frontal gyrus bilaterally, only affected in the nfvPPA group. This bilateral involvement of frontal speech networks in nfvPPA potentially affects access to compensatory mechanisms involving right hemisphere homologues. Measures of silences during reading also discriminated the PPA and control groups, but did not increase predictive accuracy. Findings suggest that a measure of relative vowel duration from of a polysyllable word repetition task may be sufficient for detecting most cases of apraxia of speech and distinguishing between nfvPPA and lvPPA

Validation of Twelve Small Kepler Transiting Planets in the Habitable Zone

We present an investigation of twelve candidate transiting planets from Kepler with orbital periods ranging from 34 to 207 days, selected from initial indications that they are small and potentially in the habitable zone (HZ) of their parent stars. Few of these objects are known. The expected Doppler signals are too small to confirm them by demonstrating that their masses are in the planetary regime. Here we verify their planetary nature by validating them statistically using the BLENDER technique, which simulates large numbers of false positives and compares the resulting light curves with the Kepler photometry. This analysis was supplemented with new follow-up observations (high-resolution optical and near-infrared spectroscopy, adaptive optics imaging, and speckle interferometry), as well as an analysis of the flux centroids. For eleven of them (KOI-0571.05, 1422.04, 1422.05, 2529.02, 3255.01, 3284.01, 4005.01, 4087.01, 4622.01, 4742.01, and 4745.01) we show that the likelihood they are true planets is far greater than that of a false positive, to a confidence level of 99.73% (3 sigma) or higher. For KOI-4427.01 the confidence level is about 99.2% (2.6 sigma). With our accurate characterization of the GKM host stars, the derived planetary radii range from 1.1 to 2.7 R_Earth. All twelve objects are confirmed to be in the HZ, and nine are small enough to be rocky. Excluding three of them that have been previously validated by others, our study doubles the number of known rocky planets in the HZ. KOI-3284.01 (Kepler-438b) and KOI-4742.01 (Kepler-442b) are the planets most similar to the Earth discovered to date when considering their size and incident flux jointly.Comment: 27 pages in emulateapj format, including tables and figures. To appear in The Astrophysical Journa

Small vessel disease pathological changes in neurodegenerative and vascular dementias concomitant with autonomic dysfunction

We performed a clinicopathological study to assess the burden of small vessel disease (SVD) type of pathological changes in elderly demented subjects, who had clinical evidence of autonomic dysfunction, either carotid sinus hypersensitivity or orthostatic hypotension or both or had exhibited unexpected repeated falls. Clinical and neuropathological diagnoses in 112 demented subjects comprised dementia with Lewy bodies (DLB), Parkinson's disease with dementia (PDD), Alzheimer's disease (AD), Mixed dementia (mostly AD‐DLB) and vascular dementia (VaD). Of these, 12 DLB subjects had no recorded unexpected falls in life and therefore no evidence of concomitant autonomic dysfunction. A further 17 subjects were assessed as aging controls without significant pathology or signs of autonomic dysfunction. We quantified brain vascular pathological changes and determined severities of neurodegenerative lesions including α‐synuclein pathology. We found moderate‐severe vascular changes and high‐vascular pathology scores (P < 0.01) in all neurodegenerative dementias and as expected in VaD compared to similar age controls. Arteriolosclerosis, perivascular spacing and microinfarcts were frequent in the basal ganglia and frontal white matter (WM) across all dementias, whereas small infarcts (<5 mm) were restricted to VaD. In a sub‐set of demented subjects, we found that vascular pathology scores were correlated with WM hyperintensity volumes determined by MRI in life (P < 0.02). Sclerotic index values were increased by ~50% in both the WM and neocortex in all dementias compared to similar age controls. We found no evidence for increased α‐synuclein deposition in subjects with autonomic dysfunction. Our findings suggest greater SVD pathological changes occur in the elderly diagnosed with neurodegenerative dementias including DLB and who develop autonomic dysfunction. SVD changes may not necessarily manifest in clinically overt symptoms but they likely confound motor or cognitive dysfunction. We propose dysautonomia promotes chronic cerebral hypoperfusion to impact upon aging‐related neurodegenerative disorders and characterize their end‐stage clinical syndromes

Subthreshold depression as a risk indicator for major depressive disorder: a systematic review of prospective studies.

Objective: In order to examine whether the incidence of major depressive disorder (MDD) is increased in subjects with subthreshold depression, or sD (clinically relevant depressive symptoms, without meeting criteria for a full-blown MDD), we conducted a review of prospective studies examining the incidence of MDD in subjects with sD. Method: A systematic literature search was conducted. For all studies, the relative risk of developing MDD was calculated, based on person-years. Results: Twenty studies (23 comparisons) were found, based on community samples, general medical patients and high-risk subjects. Most comparisons showed that subjects with sD had a consistently larger chance of developing MDD. The studies differed considerably in the definition of sD, the recency (occurrence of the last sD) and the in-/ exclusion of lifetime MDD. Conclusion: The incidence of MDD in subjects with sD is larger than in subjects without sD. Otherwise, the concept of sD is too broad to be used. In future studies, some consensus should be reached regarding the definition of sD

Anomalous thermal maturities caused by carbonaceous sediments

Sedimentary rocks such as coal and carbonaceous mudstone which contain abundant carbonaceous matter are characterized by thermal conductivity much lower than that exhibited by other common rock types, by a factor of 5–10. As a result, temperature gradients in such sediments can range up to 0.25 °Cm -1 even under conditions of average heat flow. When such steep gradients extend over a significant sedimentary thickness, temperatures of underlying rock units are elevated, causing both organic and inorganic phases to record what seem to be anomalously high levels of thermal maturity. This carbonaceous blanket insulating effect may help to explain unusual levels of maturity observed at shallow depths in the Appalachian Basin, Michigan Basin and other regions of the world with significant carbonaceous strata.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73579/1/j.1365-2117.1994.tb00074.x.pd

Scalar extensions of triangulated categories

Given a triangulated category over a field $K$ and a field extension $L/K$, we investigate how one can construct a triangulated category over $L$. Our approach produces the derived category of the base change scheme $X_L$ if the category one starts with is the bounded derived category of a smooth projective variety $X$ over $K$ and the field extension is finite and Galois. We also investigate how the dimension of a triangulated category behaves under scalar extensions.Comment: 15 pages, comments welcom

Reinforcement learning or active inference?

This paper questions the need for reinforcement learning or control theory when optimising behaviour. We show that it is fairly simple to teach an agent complicated and adaptive behaviours using a free-energy formulation of perception. In this formulation, agents adjust their internal states and sampling of the environment to minimize their free-energy. Such agents learn causal structure in the environment and sample it in an adaptive and self-supervised fashion. This results in behavioural policies that reproduce those optimised by reinforcement learning and dynamic programming. Critically, we do not need to invoke the notion of reward, value or utility. We illustrate these points by solving a benchmark problem in dynamic programming; namely the mountain-car problem, using active perception or inference under the free-energy principle. The ensuing proof-of-concept may be important because the free-energy formulation furnishes a unified account of both action and perception and may speak to a reappraisal of the role of dopamine in the brain

Hyperbolic planforms in relation to visual edges and textures perception

We propose to use bifurcation theory and pattern formation as theoretical probes for various hypotheses about the neural organization of the brain. This allows us to make predictions about the kinds of patterns that should be observed in the activity of real brains through, e.g. optical imaging, and opens the door to the design of experiments to test these hypotheses. We study the specific problem of visual edges and textures perception and suggest that these features may be represented at the population level in the visual cortex as a specific second-order tensor, the structure tensor, perhaps within a hypercolumn. We then extend the classical ring model to this case and show that its natural framework is the non-Euclidean hyperbolic geometry. This brings in the beautiful structure of its group of isometries and certain of its subgroups which have a direct interpretation in terms of the organization of the neural populations that are assumed to encode the structure tensor. By studying the bifurcations of the solutions of the structure tensor equations, the analog of the classical Wilson and Cowan equations, under the assumption of invariance with respect to the action of these subgroups, we predict the appearance of characteristic patterns. These patterns can be described by what we call hyperbolic or H-planforms that are reminiscent of Euclidean planar waves and of the planforms that were used in [1, 2] to account for some visual hallucinations. If these patterns could be observed through brain imaging techniques they would reveal the built-in or acquired invariance of the neural organization to the action of the corresponding subgroups.Comment: 34 pages, 11 figures, 2 table