5,865 research outputs found
Cognitive pathways to belief in karma and belief in God
Supernatural beliefs are ubiquitous around the world, and mounting evidence indicates that these beliefs partly rely on intuitive, cross-culturally recurrent cognitive processes. Specifically, past research has focused on humans’ intuitive tendency to perceive minds as part of the cognitive foundations of belief in a personified God — an agentic, morally concerned supernatural entity. However, much less is known about belief in karma – another culturally widespread but ostensibly non-agentic supernatural entity reflecting ethical causation across reincarnations. In two studies and four high-powered samples, including mostly-Christian Canadians and mostly-Hindu Indians (Study 1, N = 2006) and mostly-Christian Americans and Singaporean Buddhists (Study 2, N = 1752), we provide the first systematic empirical investigation of the cognitive intuitions underlying various forms of belief in karma. We used path analyses to (1) replicate tests of the previously documented cognitive predictors of belief in God, (2) test whether this same network of variables predicts belief in karma, and (3) examine the relative contributions of cognitive and cultural variables to both sets of beliefs. We found that cognitive tendencies toward intuitive thinking, mentalizing, dualism, and teleological thinking predicted a variety of beliefs about karma—including morally-laden, non-agentic, and agentic conceptualizations—above and beyond the variability explained by cultural learning about karma across cultures. These results provide further evidence for an independent role for both culture and cognition in supporting diverse types of supernatural beliefs in distinct cultural contexts
Incorporation of feedback during beat synchronization is an index of neural maturation and reading skills
Speech communication involves integration and coordination of sensory perception and motor production, requiring precise temporal coupling. Beat synchronization, the coordination of movement with a pacing sound, can be used as an index of this sensorimotor timing. We assessed adolescents’ synchronization and capacity to correct asynchronies when given online visual feedback. Variability of synchronization while receiving feedback predicted phonological memory and reading sub-skills, as well as maturation of cortical auditory processing; less variable synchronization during the presence of feedback tracked with maturation of cortical processing of sound onsets and resting gamma activity. We suggest the ability to incorporate feedback during synchronization is an index of intentional, multimodal timing-based integration in the maturing adolescent brain. Precision of temporal coding across modalities is important for speech processing and literacy skills that rely on dynamic interactions with sound. Synchronization employing feedback may prove useful as a remedial strategy for individuals who struggle with timing-based language learning impairments
The identification of mitochondrial DNA variants in glioblastoma multiforme
Background:
Mitochondrial DNA (mtDNA) encodes key proteins of the electron transfer chain (ETC), which produces ATP through oxidative phosphorylation (OXPHOS) and is essential for cells to perform specialised functions. Tumor-initiating cells use aerobic glycolysis, a combination of glycolysis and low levels of OXPHOS, to promote rapid cell proliferation and tumor growth. Glioblastoma multiforme (GBM) is an aggressively malignant brain tumor and mitochondria have been proposed to play a vital role in GBM tumorigenesis.
Results:
Using next generation sequencing and high resolution melt analysis, we identified a large number of mtDNA variants within coding and non-coding regions of GBM cell lines and predicted their disease-causing potential through in silico modeling. The frequency of variants was greatest in the D-loop and origin of light strand replication in non-coding regions. ND6 was the most susceptible coding gene to mutation whilst ND4 had the highest frequency of mutation. Both genes encode subunits of complex I of the ETC. These variants were not detected in unaffected brain samples and many have not been previously reported. Depletion of HSR-GBM1 cells to varying degrees of their mtDNA followed by transplantation into immunedeficient mice resulted in the repopulation of the same variants during tumorigenesis. Likewise, de novo variants identified in other GBM cell lines were also incorporated. Nevertheless, ND4 and ND6 were still the most affected genes. We confirmed the presence of these variants in high grade gliomas.
Conclusions:
These novel variants contribute to GBM by rendering the ETC. partially dysfunctional. This restricts metabolism to anaerobic glycolysis and promotes cell proliferation
Diastereoselective Photoredox-Catalyzed [3 + 2] Cycloadditions of N-Sulfonyl Cyclopropylamines with Electron-Deficient Olefins
Association and liquid structure of pyridine-acetic acid mixtures determined from neutron scattering using a ‘free proton’ EPSR simulation model
Hydrogen-bonded molecular acetic acid chains are observed in acid–base mixtures from small angle neutron diffraction.</p
The clustering of intermediate redshift quasars as measured by the Baryon Oscillation Spectroscopic Survey
We measure the quasar two-point correlation function over the redshift range
2.2<z<2.8 using data from the Baryon Oscillation Spectroscopic Survey. We use a
homogeneous subset of the data consisting of 27,129 quasars with spectroscopic
redshifts---by far the largest such sample used for clustering measurements at
these redshifts to date. The sample covers 3,600 square degrees, corresponding
to a comoving volume of 9.7(Gpc/h)^3 assuming a fiducial LambdaCDM cosmology,
and it has a median absolute i-band magnitude of -26, k-corrected to z=2. After
accounting for redshift errors we find that the redshift space correlation
function is fit well by a power-law of slope -2 and amplitude s_0=(9.7\pm
0.5)Mpc/h over the range 3<s<25Mpc/h. The projected correlation function, which
integrates out the effects of peculiar velocities and redshift errors, is fit
well by a power-law of slope -1 and r_0=(8.4\pm 0.6)Mpc/h over the range
4<R<16Mpc/h. There is no evidence for strong luminosity or redshift dependence
to the clustering amplitude, in part because of the limited dynamic range in
our sample. Our results are consistent with, but more precise than, previous
measurements at similar redshifts. Our measurement of the quasar clustering
amplitude implies a bias factor of b~3.5 for our quasar sample. We compare the
data to models to constrain the manner in which quasars occupy dark matter
halos at z~2.4 and infer that such quasars inhabit halos with a characteristic
mass of ~10^{12}Msun/h with a duty cycle for the quasar activity of 1 per
cent.Comment: 20 pages, 18 figures. Minor modifications to match version accepted
by journa
A Widely-Separated, Highly-Occluded Companion to the Nearby Low-Mass T Tauri Star TWA 30
We report the discovery of TWA 30B, a wide (~3400 AU), co-moving M dwarf
companion to the nearby (~42 pc) young star TWA 30. Companionship is confirmed
from their statistically consistent proper motions and radial velocities, as
well as a chance alignment probability of only 0.08%. Like TWA 30A, the
spectrum of TWA 30B shows signatures of an actively accreting disk (H I and
alkali line emission) and forbidden emission lines tracing outflowing material
([O I], [O II], [O III], [S II], and [N II]). We have also detected [C I]
emission in the optical data, marking the first such detection of this line in
a pre-main sequence star. Negligible radial velocity shifts in the emission
lines relative to the stellar frame of rest (Delta V < 30 km/s) indicate that
the outflows are viewed in the plane of the sky and that the corresponding
circumstellar disk is viewed edge-on. Indeed, TWA 30B appears to be heavily
obscured by its disk, given that it is 5 magnitudes fainter than TWA 30A at
K-band despite having a slightly earlier spectral type (M4 versus M5). The
near-infrared spectrum of TWA 30B also evinces an excess that varies on day
timescales, with colors that follow classical T Tauri tracks as opposed to
variable reddening (as is the case for TWA 30A). Multi-epoch data show this
excess to be well-modeled by a blackbody component with temperatures ranging
from 630 to 880 K and emitting areas that scale inversely with the temperature.
The variable excess may arise from disk structure such as a rim or a warp at
the inner disk edge located at a radial distance of ~3-5 R_sun. As the second
and third closest actively accreting and outflowing stars to the Sun (after TWA
3), TWA 30AB presents an ideal system for detailed study of star and planetary
formation processes at the low-mass end of the hydrogen-burning spectrum.Comment: 34 pages, 6 figures, AJ in press; Replaced Figure 4 with a better
color version, added 3 references and slightly amended Section 3.2.
Factors Limiting the Spread of the Protective Symbiont \u3cem\u3eHamiltonella defensa\u3c/em\u3e in \u3cem\u3eAphis craccivora\u3c/em\u3e Aphids
Many insects are associated with heritable symbionts that mediate ecological interactions, including host protection against natural enemies. The cowpea aphid, Aphis craccivora, is a polyphagous pest that harbors Hamiltonella defensa, which defends against parasitic wasps. Despite this protective benefit, this symbiont occurs only at intermediate frequencies in field populations. To identify factors constraining H. defensa invasion in Ap. craccivora, we estimated symbiont transmission rates, performed fitness assays, and measured infection dynamics in population cages to evaluate effects of infection. Similar to results with the pea aphid, Acyrthosiphon pisum, we found no consistent costs to infection using component fitness assays, but we did identify clear costs to infection in population cages when no enemies were present. Maternal transmission rates of H. defensa in Ap. craccivora were high (ca. 99%) but not perfect. Transmission failures and infection costs likely limit the spread of protective H. defensa in Ap. craccivora. We also characterized several parameters of H. defensa infection potentially relevant to the protective phenotype. We confirmed the presence of H. defensa in aphid hemolymph, where it potentially interacts with endoparasites, and performed real-time quantitative PCR (qPCR) to estimate symbiont and phage abundance during aphid development. We also examined strain variation of H. defensa and its bacteriophage at multiple loci, and despite our lines being collected in different regions of North America, they were infected with a nearly identical strains of H. defensa and APSE4 phage. The limited strain diversity observed for these defensive elements may result in relatively static protection profile for this defensive symbiosis
Density Matrix Renormalisation Group Approach to the Massive Schwinger Model
The massive Schwinger model is studied, using a density matrix
renormalisation group approach to the staggered lattice Hamiltonian version of
the model. Lattice sizes up to 256 sites are calculated, and the estimates in
the continuum limit are almost two orders of magnitude more accurate than
previous calculations. Coleman's picture of `half-asymptotic' particles at
background field theta = pi is confirmed. The predicted phase transition at
finite fermion mass (m/g) is accurately located, and demonstrated to belong in
the 2D Ising universality class.Comment: 38 pages, 18 figures, submitted to PR
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