julilili42/papers huggingface dataset:
Me or Not Me: Causal Inference of Agency in goal-directed actions
2011-09-23

The perception of own actions is affected by both visual information and predictions derived from internal forward models [1]. The integration of these information sources depends critically on whether visual consequences are associated with one's own action (sense of agency) or with changes in the external world unrelated to the action [2,3] and the accuracy of integrated signals [4,5]. The attribution of percepts to consequences of own actions should thus depend on the consistency between internally predicted and actual visual signals. METHODS. To test this idea, we used a virtual-reality setup to manipulate the consistency between pointing movements and their visual consequences and investigated the influence of this manipulation on self-action perception. We then asked whether a Bayesian causal inference model, which assumes a latent agency variable controlling the attributed influence of the own action on perceptual consequences [2,3], accounts for the empirical data: if the visual stimulus was attributed to the own action, visual and internal information should fuse in a Bayesian optimal manner, while this should not be the case if the percept was attributed to external influences. The model assumes that both the visual feedback and the internal estimate are directly caused by the (unobserved) real motor state. RESULTS AND CONCLUSION. The model correctly predicts the data, showing that small deviations between predicted and actual visual information were attributed to one's own action. This was not the case for large deviations, where subjects relied more on internal information. We discuss the performance of this causal inference model in comparison to alternative biologically feasible statistical models, applying methods for Bayesian model comparison. [1] Wolpert et al., Science, 269, 1995. [2] Körding et al., PLoS ONE, 2(9), 2007. [3] Shams & Beierholm, TiCS, 14, 2010. [4] Burge et al., JoVision, 8(4), 2008. [5] Alais & Burr, CurBio, 14, 2004.
Asymmetric attention foci during multiple object tracking: Evidence from distractor displacements
2011-09-23

Several activities such as driving or video-gaming require the ability to track several objects simultaneously. This ability is studied in the multiple object tracking paradigm (MOT). Observers track targets among identical distractors. Previous research suggests that distractors are inhibited during MOT by narrowing the attention foci on targets to compensate decreasing target-distractor distances. In four experiments, we tested whether the sizes of the attention foci are dependent solely on inter-object spacing and thus symmetrical around targets or whether they omit distractor locations. During brief flashes, we displaced each distractor on a circular path around its associated target object thus maintaining inter-object spacing. Distractor displacements would not impair tracking performance if the attention foci were symmetrical around targets whereas displacements would decrease performance if the attention foci were asymmetric around targets. In Experiment 1a, we observed impaired tracking performance when distractors were displaced during tracking. Changing movement directions of distractors improved performance. Experiment 1b revealed direction changes of distractors to increase performance only when they are unique for distractors, whereas target direction changes impaired tracking in general. Furthermore, we tested whether changes in the global (Experiment 2) or local configuration (Experiment 3) of objects can account for the effect of distractor displacements. In Experiment 2, we varied the number of displaced distractors. We observed tracking performance declining linearly. In Experiment 3, we controlled for local configuration changes. During each trial, three distractors were displaced by 50°, 100°, or 150° around their associated target. One distractor was not displaced. Tracking was less accurate with larger displacements. However, for 50° displacements performance was equal to no displacements. We conclude that the attention foci omit distractor positions and that attention is not symmetrically distributed around targets. We argue in favor of a flexible resource model deploying attention asymmetrically among and around tracked targets.
INFINITE DIMENSIONAL STATIONARY RANDOM FIELDS OVER A LOCALLY COMPACT ABELIAN GROUP
2011-09-23

In this paper we consider spectral representation of infinite dimensional stationary random fields over an abelian locally compact (or LCA) group, and then extend the results of earlier authors who consider wide sense Markov random fields over a Euclidean group R n to the general LCA group context and obtain minimality properties. We also indicate possibilities of some extensions of these results to certain nonstationary classes.
FraH Is Required for Reorganization of Intracellular Membranes during Heterocyst Differentiation in Anabaena sp. Strain PCC 7120
2011-09-24

ABSTRACT In the filamentous, heterocyst-forming cyanobacteria, two different cell types, the CO 2 -fixing vegetative cells and the N 2 -fixing heterocysts, exchange nutrients and regulators for diazotrophic growth. In the model organism Anabaena sp. strain PCC 7120, inactivation of fraH produces filament fragmentation under conditions of combined nitrogen deprivation, releasing numerous isolated heterocysts. Transmission electron microscopy of samples prepared by either high-pressure cryo-fixation or chemical fixation showed that the heterocysts of a Δ fraH mutant lack the intracellular membrane system structured close to the heterocyst poles, known as the honeycomb, that is characteristic of wild-type heterocysts. Using a green fluorescent protein translational fusion to the carboxyl terminus of FraH (FraH-C-GFP), confocal microscopy showed spots of fluorescence located at the periphery of the vegetative cells in filaments grown in the presence of nitrate. After incubation in the absence of combined nitrogen, localization of FraH-C-GFP changed substantially, and the GFP fluorescence was conspicuously located at the cell poles in the heterocysts. Fluorescence microscopy and deconvolution of images showed that GFP fluorescence originated mainly from the region next to the cyanophycin plug present at the heterocyst poles. Intercellular transfer of the fluorescent tracers calcein (622 Da) and 5-carboxyfluorescein (374 Da) was either not impaired or only partially impaired in the Δ fraH mutant, suggesting that FraH is not important for intercellular molecular exchange. Location of FraH close to the honeycomb membrane structure and lack of such structure in the Δ fraH mutant suggest a role of FraH in reorganization of intracellular membranes, which may involve generation of new membranes, during heterocyst differentiation.
Foundation characteristics of the soils of different parts of Nepal
2011-09-24

This paper deals with foundation characteristics of the soils of different parts of Nepal. In this paper, multiple approaches were adopted to explore foundation characteristic s of the soil. In this study 14 sites from different parts of the country were selected; 2 sites from the hilly region, 2 sites from the inner Terai and 10 sites from the Terai. In each site two test sites were selected. In each test site simplified penetration apparatus (SPA) tests were carried out and were accompanied by the auger tests. Soil samples from different depths in each site were collected for the direct shear test, soil classification, LL PL test, density and other tests and these tests were carried out in laboratory. Bearing capacity of the soils thus obtained from the laboratory was compared with the soil types of certain depth and the Nc value at that depth. From the study it was found that the Nc value depends upon the types of the soil and the compactness of the soils. This study showed that Nc value can be converted in to the ultimate bearing capacity by multiplying the obtained Nc value by the factor of 35 within 80% confidence. Resistivity measurements were carried out only to explore the suitability of the sites for the purposed construction of substations in terms of earthing. Resistivity measurement showed that the sites are suitable for the construction of purposed substations.
Neuropathology in Mice Expressing Mouse Alpha-Synuclein
2011-09-26

α-Synuclein (αSN) in human is tightly linked both neuropathologically and genetically to Parkinson's disease (PD) and related disorders. Disease-causing properties in vivo of the wildtype mouse ortholog (mαSN), which carries a threonine at position 53 like the A53T human mutant version that is genetically linked to PD, were never reported. To this end we generated mouse lines that express mαSN in central neurons at levels reaching up to six-fold compared to endogenous mαSN. Unlike transgenic mice expressing human wildtype or mutant forms of αSN, these mαSN transgenic mice showed pronounced ubiquitin immunopathology in spinal cord and brainstem. Isoelectric separation of mαSN species revealed multiple isoforms including two Ser129-phosphorylated species in the most severely affected brain regions. Neuronal Ser129-phosphorylated αSN occurred in granular and small fibrillar aggregates and pathological staining patterns in neurites occasionally revealed a striking ladder of small alternating segments staining either for Ser129-phosphorylated αSN or ubiquitin but not both. Axonal degeneration in long white matter tracts of the spinal cord, with breakdown of myelin sheaths and degeneration of neuromuscular junctions with loss of integrity of the presynaptic neurofilament network in mαSN transgenic mice, was similar to what we have reported for mice expressing human αSN wildtype or mutant forms. In hippocampal neurons, the mαSN protein accumulated and was phosphorylated but these neurons showed no ubiquitin immunopathology. In contrast to the early-onset motor abnormalities and muscle weakness observed in mice expressing human αSN, mαSN transgenic mice displayed only end-stage phenotypic alterations that manifested alongside with neuropathology. Altogether these findings show that increased levels of wildtype mαSN does not induce early-onset behavior changes, but drives end-stage pathophysiological changes in murine neurons that are strikingly similar to those evoked by expression of human wildtype or mutant forms.
The biological standard of living in early nineteenth‐century West Africa: new anthropometric evidence for northern Ghana and Burkina Faso1
2011-09-26

West Africans are on average shorter than Europeans today. Whether this was already the case at the end of the Atlantic slave trade is an important question for the history of nutrition and physical welfare. We present the first study of changing heights for people born mostly in what are now northern Ghana and Burkina Faso during the early nineteenth century. The dataset, not used before for anthropometry, documents men born between 1800 and 1849. Mostly purchased from slave owners, they were recruited into the Dutch army to serve in the Dutch East Indies. We find that height development was stagnant between 1800 and 1830 and deteriorated strongly during the 1840s. In international comparison and after taking selectivity issues into account, these Ghanaian and Burkinabe recruits were notably shorter than north‐western Europeans but not shorter than southern Europeans during this period.
Expression of stromal‐cell‐derived factor‐1 (SDF‐1): a predictor of ischaemic stroke?
2011-09-26

Background and purpose: Platelet stromal‐cell‐derived factor‐1 (SDF‐1) plays a pivotal role in angiogenesis and the regeneration of ischaemic tissue through the regulation of haematopoietic progenitor cells and is upregulated at the sites of vascular injury and platelet activation. Thus, SDF‐1 has recently been discussed as a predictor in ischaemic diseases such as acute myocardial infarction. However, no clinical data pertinent to the investigation of the platelet SDF‐1 expression in patients with stroke are available. Methods: We consecutively evaluated 196 patients who were admitted to the stroke unit with symptoms suspected for stroke. Surface expression of the platelet activation markers (P‐selectin and GPIb) and the expression of platelet‐bound SDF‐1 were determined by two‐colour whole blood flow cytometry. Results: Patients with transient ischaemic attack (TIA) as well as with ischaemic stroke showed similar levels of SDF‐1 expression on hospital admission compared with patients with non‐ischaemic (NI) events and with 30 healthy controls (TIA (mean fluorescence intensity ± SD): 31.5 ± 18.2 vs. NI: 26.4 ± 15.7; P = 0.361; stroke: 28.7 ± 19.8 vs. NI; P = 0.943; control: 26.1 ± 11.3; P &gt; 0.05 compared with all). Platelet SDF‐1 expression showed a trend with the severity of stroke according to National Institute of Health Stroke Scale score ( r = 0.125; P = 0.085), but significantly correlated with the peak levels of C‐reactive protein ( r = 0.218; P = 0.002) and with the levels of platelet activation (P‐selectin: r = 0.389; P = 0.001). Multifactorial analysis of covariance revealed a significant influence on platelet SDF‐1 expression by smoking ( P = 0.019). Conclusions: Platelet SDF‐1 surface expression did not show any significant difference in patients with TIA and ischaemic stroke compared with patients with NI events. Thus, single biomarker evaluation of platelet SDF‐1 surface expression is not helpful to predict ischaemic stroke.
Gαi2- and Gαi3-Specific Regulation of Voltage-Dependent L-Type Calcium Channels in Cardiomyocytes
2011-09-26

Our data provide novel evidence for an isoform-specific modulation of L-VDCC by Gα(i) proteins. In particular, loss of Gα(i2) is reflected by alterations in channel kinetics and likely involves an impairment of the ERK1/2 signalling pathway.
Magnetism and mineralogy of Almahata Sitta polymict ureilite (= asteroid 2008 TC3): Implications for the ureilite parent body magnetic field
2011-09-26

Abstract– The Almahata Sitta meteorite is the first case of recovered extraterrestrial material originating from an asteroid that was detected in near Earth space shortly before entering and exploding in the high atmosphere. The aims of our project within the 2008 TC 3 consortium were investigating Almahata Sitta’s (AS) magnetic signature, phase composition and mineralogy, focussing on the opaque minerals, and gaining new insights into the magnetism of the ureilite parent body (UPB). We report on the general magnetic properties and behavior of Almahata Sitta and try to place the results in context with the existing data set on ureilites and ureilite parent body models. The magnetic signature of AS is dominated by a set of low‐Ni kamacites with large grain sizes. Additional contributions come from micron‐sized kamacites, suessite, (Cr) troilite, and daubreelite, mainly found in the olivine grains adjacent to carbon‐rich veins. Our results show that the paleomagnetic signal is of extraterrestrial origin as can be seen by comparing with laboratory produced magnetic records (IRM). Four types of kamacite (I–IV) have been recognized in the sample. The elemental composition of the ureilite vein metal Kamacite I (particularly Co) clearly differs from the other kamacites (II‐IV), which are considered to be indigenous. Element ratios of kamacite I indicate that it was introduced into the UPB by an impactor, supporting the conclusions of Gabriel and Pack (2009) .
Remarks on Christopher Beeley,Gregory of Nazianzus on the Trinity and the Knowledge of God. In Your light we shall see light
2011-09-26

The trinitarian theology of Gregory of Nazianzus is an important topic in patristic studies which is too often ignored by modern scholars. The aim of Beeley's book (like that of John McGuckin) is to deepen the study of this theologian who became very important for the later Orthodox tradition. Beeley wants to view Gregory not simply as one of the three Cappadocians or to make a short systematisation of the Theological Orations ( or . 27–31), but rather to see his theology as a whole in its historical context. This makes the work an important contribution to historical studies in patristics, and I have learnt much from reading this book. The following remarks, even when critical, are intended to raise new topics for discussion, though controversial in some aspects.
Phenotypic spectrum associated with CASK loss-of-function mutations
2011-09-27

Background Heterozygous mutations in the CASK gene in Xp11.4 have been shown to be associated with a distinct brain malformation phenotype in females, including disproportionate pontine and cerebellar hypoplasia. Methods The study characterised the CASK alteration in 20 new female patients by molecular karyotyping, fluorescence in situ hybridisation, sequencing, reverse transcriptase (RT) and/or quantitative real-time PCR. Clinical and brain imaging data of a total of 25 patients were reviewed. Results 11 submicroscopic copy number alterations, including nine deletions of ∼11 kb to 4.5 Mb and two duplications, all covering (part of) CASK , four splice, four nonsense, and one 1 bp deletion are reported. These heterozygous CASK mutations most likely lead to a null allele. Brain imaging consistently showed diffuse brainstem and cerebellar hypoplasia with a dilated fourth ventricle, but of remarkably varying degrees. Analysis of 20 patients in this study, and five previously reported patients, revealed a core clinical phenotype comprising severe developmental delay/intellectual disability, severe postnatal microcephaly, often associated with growth retardation, (axial) hypotonia with or without hypertonia of extremities, optic nerve hypoplasia, and/or other eye abnormalities. A recognisable facial phenotype emerged, including prominent and broad nasal bridge and tip, small or short nose, long philtrum, small chin, and/or large ears. Conclusions These findings define the phenotypic spectrum associated with CASK loss-of-function mutations. The combination of developmental and brain imaging features together with mild facial dysmorphism is highly suggestive of this disorder and should prompt subsequent testing of the CASK gene.
Raman spectroscopy for the non‐contact and non‐destructive monitoring of collagen damage within tissues
2011-09-27

Abstract The non‐destructive and label‐free monitoring of extracellular matrix (ECM) remodeling and degradation processes is a great challenge. Raman spectroscopy is a non‐contact method that offers the possibility to analyze ECM in situ without the need for tissue processing. Here, we employed Raman spectroscopy for the detection of heart valve ECM, focusing on collagen fibers. We screened the leaflets of porcine aortic valves either directly after dissection or after treatment with collagenase. By comparing the fingerprint region of the Raman spectra of control and treated tissues (400–1800 cm –1 ), we detected no significant differences based on Raman shifts; however, we found that increasing collagen degradation translated into decreasing Raman signal intensities. After these proof‐of‐principal experiments, we compared Raman spectra of native and cryopreserved valve tissues and revealed that the signal intensities of the frozen samples were significantly lower compared to those of native tissues, similar to the data seen in the enzymatically‐degraded tissues. In conclusion, our data demonstrate that Raman microscopy is a promising, non‐destructive and non‐contact tool to probe ECM state in situ . (© 2012 WILEY‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)
Reversal of UVA Skin Photosensitivity and DNA Damage in Kidney Transplant Recipients by Replacing Azathioprine
2011-09-27

Azathioprine is associated with enhanced skin photosensitivity to ultraviolet A (UVA) and leads to incorporation of 6-thioguanine (6-TG) into DNA of dividing cells. Unlike canonical DNA, 6-TG DNA is damaged by UVA, which comprises more than 90% of the ultraviolet reaching earth. Skin photosensitivity to UVA and UVB was measured in 48 kidney transplant patients immunosuppressed either by azathioprine (n = 32) or mycophenolate (n = 16). In 23 patients, azathioprine was subsequently replaced by mycophenolate and skin photosensitivity, DNA 6-TG content in peripheral blood mononuclear cells, and susceptibility to UVA-induced DNA damage were monitored for up to 2 years. The mean minimal erythema dose to UVA on azathioprine was twofold lower than on mycophenolate. Three months after replacing azathioprine by mycophenolate mofetil, the minimal erythema dose to UVA had increased from 15 to 25 J/cm(2) (p < 0.001) accompanied by reduced DNA 6-TG content. P53 protein expression in irradiated skin indicated reduced susceptibility to UVA-induced DNA damage. 6-TG DNA in peripheral blood mononuclear cells remained measurable for over 2 years. Replacing azathioprine selectively reduced the skin photosensitivity to UVA, attenuated UVA-induced skin DNA damage, and is likely based on incorporated 6-TG in DNA.
Financial market spillovers around the globe
2011-09-27

This article investigates the transmission of return and volatility spillovers around the globe. It draws on index futures of three representative indices, namely the Dow Jones Euro Stoxx 50, the S&amp;P 500 and the Nikkei 225. Devolatized returns and realized volatilities are modelled separately using a Structural Vector Autoregressive (SVAR) model, thereby accounting for the particular sequential time structure of the trading venues. Within this framework, we test hypotheses in the spirit of Granger causality tests, investigate the short-run dynamics in the three markets using Impulse Response (IR) functions, and identify leadership effects through variance decomposition. Our key results are as follows. We find weak and short-lived return spillovers, in particular from the USA to Japan. Volatility spillovers are more pronounced and persistent. The information from the home market is most important for both returns and volatilities; the contribution from foreign markets is less pronounced in the case of returns than in the case of volatility. Possible gains in terms of forecasting precision when applying our modelling strategy are illustrated by a forecast evaluation.
The correspondence between proximal phalanx morphology and locomotion: Implications for inferring the locomotor behavior of fossil catarrhines
2011-09-27

Abstract Phalanges are considered to be highly informative in the reconstruction of extinct primate locomotor behavior since these skeletal elements directly interact with the substrate during locomotion. Variation in shaft curvature and relative phalangeal length has been linked to differences in the degree of suspension and overall arboreal locomotor activities. Building on previous work, this study investigated these two skeletal characters in a comparative context to analyze function, while taking evolutionary relationships into account. This study examined the correspondence between proportions of suspension and overall substrate usage observed in 17 extant taxa and included angle of curvature and relative phalangeal length. Predictive models based on these traits are reported. Published proportions of different locomotor behaviors were regressed against each phalangeal measurement and a size proxy. The relationship between each behavior and skeletal trait was investigated using ordinary least‐squares, phylogenetic generalized least‐squares (pGLS), and two pGLS transformation methods to determine the model of best‐fit. Phalangeal curvature and relative length had significant positive relationships with both suspension and overall arboreal locomotion. Cross‐validation analyses demonstrated that relative length and curvature provide accurate predictions of relative suspensory behavior and substrate usage in a range of extant species when used together in predictive models. These regression equations provide a refined method to assess the amount of suspensory and overall arboreal locomotion characterizing species in the catarrhine fossil record. Am J Phys Anthropol, 2011. © 2011 Wiley‐Liss, Inc.