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https://www.readbyqxmd.com/read/28644991/glimpses-into-the-blind-spot-social-interaction-and-autism
#1
REVIEW
Kristen Bottema-Beutel
A primary feature of autism spectrum disorder (ASD) is marked difficulty in social interactions. Despite the centrality of social interaction differences to the clinical presentation of ASD, only a small portion of research in this field characterizes interaction in everyday social contexts. This theoretical paper reviews the growing corpus of interactional research on ASD, including discourse analysis (DA) and conversation analysis (CA) approaches. DA and CA are micro-analytic methods aimed at understanding the organizational structure of, and actions pursued within, social encounters...
June 16, 2017: Journal of Communication Disorders
https://www.readbyqxmd.com/read/28644874/position-and-orientation-inference-via-on-board-triangulation
#2
Madhu Advani, Daniel S Weile
This work proposes a new approach to determine the spatial location and orientation of an object using measurements performed on the object itself. The on-board triangulation algorithm we outline could be implemented in lieu of, or in addition to, well-known alternatives such as Global Positioning System (GPS) or standard triangulation, since both of these correspond to significantly different geometric pictures and necessitate different hardware and algorithms. We motivate the theory by describing situations in which on-board triangulation would be useful and even preferable to standard methods...
2017: PloS One
https://www.readbyqxmd.com/read/28644840/linking-structure-and-activity-in-nonlinear-spiking-networks
#3
Gabriel Koch Ocker, Krešimir Josić, Eric Shea-Brown, Michael A Buice
Recent experimental advances are producing an avalanche of data on both neural connectivity and neural activity. To take full advantage of these two emerging datasets we need a framework that links them, revealing how collective neural activity arises from the structure of neural connectivity and intrinsic neural dynamics. This problem of structure-driven activity has drawn major interest in computational neuroscience. Existing methods for relating activity and architecture in spiking networks rely on linearizing activity around a central operating point and thus fail to capture the nonlinear responses of individual neurons that are the hallmark of neural information processing...
June 23, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28644764/interventions-to-improve-breastfeeding-self-efficacy-and-resultant-breastfeeding-rates-a-systematic-review-and-meta-analysis
#4
Meredith Brockway, Karen Benzies, K Alix Hayden
BACKGROUND: Maternal breastfeeding self-efficacy (BSE) is reflective of a mother's confidence in breastfeeding and is a modifiable factor that may improve breastfeeding rates. Breastfeeding self-efficacy theory purports that women with higher BSE will have better breastfeeding outcomes. Research aim: The aim of this systematic review was to explore the theoretical link between BSE and breastfeeding outcomes by investigating (a) if interventions to improve BSE were successful and (b) if improvements in BSE resulted in improved breastfeeding rates...
June 1, 2017: Journal of Human Lactation: Official Journal of International Lactation Consultant Association
https://www.readbyqxmd.com/read/28644729/promoting-prenatal-exercise-from-a-sociocultural-and-life-course-perspective-an-embodied-conceptual-framework
#5
Shannon Jette, Julie Maier, Katelyn Esmonde, Cherise Davis
PURPOSE: Prenatal exercise is a health behavior that is receiving growing attention amid concern that women in Western societies are gaining excess weight during pregnancy and contributing to future obesity in both the mother and child. In this article, we draw on insights from the fields of social epidemiology and social theory of the body to examine existing prenatal exercise interventions and to propose a multidimensional framework intended to guide future theorizing and intervention design...
June 23, 2017: Research Quarterly for Exercise and Sport
https://www.readbyqxmd.com/read/28644676/is-a-trineutron-resonance-lower-in-energy-than-a-tetraneutron-resonance
#6
S Gandolfi, H-W Hammer, P Klos, J E Lynn, A Schwenk
We present quantum Monte Carlo calculations of few-neutron systems confined in external potentials based on local chiral interactions at next-to-next-to-leading order in chiral effective field theory. The energy and radial densities for these systems are calculated in different external Woods-Saxon potentials. We assume that their extrapolation to zero external-potential depth provides a quantitative estimate of three- and four-neutron resonances. The validity of this assumption is demonstrated by benchmarking with an exact diagonalization in the two-body case...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644673/limitations-of-particle-based-spasers
#7
Günter Kewes, Kathrin Herrmann, Rogelio Rodríguez-Oliveros, Alexander Kuhlicke, Oliver Benson, Kurt Busch
We present a semiclassical analytic model for spherical core-shell surface plasmon lasers. Within this model, we drop the widely used one-mode approximations in favor of fully electromagnetic Mie theory. This allows for incorporation of realistic gain relaxation rates that so far are massively underestimated. Especially, higher order modes can undermine and even reverse the beneficial effects of the strong Purcell effect in such systems. Our model gives a clear view on gain and resonator requirements, as well as on the output characteristics that will help experimenters to design more efficient particle-based spasers...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644661/soft-photon-and-graviton-theorems-in-effective-field-theory
#8
Henriette Elvang, Callum R T Jones, Stephen G Naculich
Extensions of the photon and graviton soft theorems are derived in 4D local effective field theories with massless particles of arbitrary spin. We prove that effective operators can result in new terms in the soft theorems at subleading order for photons and subsubleading order for gravitons. The new soft terms are unique, and we provide a complete classification of all local operators responsible for such modifications. We show that no local operators can modify the subleading soft graviton theorem. The soft limits are taken in a manifestly on-locus manner using a complex double deformation of the external momenta...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644655/formation-of-vacancies-in-si-and-ge-based-clathrates-role-of-electron-localization-and-symmetry-breaking
#9
Amrita Bhattacharya, Christian Carbogno, Bodo Böhme, Michael Baitinger, Yuri Grin, Matthias Scheffler
The formation of framework vacancies in Si- and Ge-based type-I clathrates is studied using density-functional theory as a function of filling the cages with K and Ba atoms. Our analysis reveals the relevance of structural disorder, geometric relaxation, and electronic saturation as well as vibrational and configurational entropy. In the Si clathrates, we find that vacancies are unstable, but very differently, in Ge clathrates, up to three vacancies per unit cell can be stabilized. This contrasting behavior is largely driven by the different energy gain on populating the electronic vacancy states, which originates from the different degree of localization of the valence orbitals of Si and Ge...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644653/dielectric-anisotropy-of-the-gap-si-001-interface-from-first-principles-theory
#10
Pankaj Kumar, Charles H Patterson
First-principles calculations of the dielectric anisotropy of the GaP/Si(001) interface are compared to the anisotropy extracted from reflectance measurements on GaP thin films on Si(001) [O. Supplie et al., Phys. Rev. B 86, 035308 (2012)PRBMDO1098-012110.1103/PhysRevB.86.035308]. Optical excitations from two states localized in several Si layers adjacent to the interface result in the observed anisotropy of the interface. The calculations show excellent agreement with experiment only for a gapped interface with a P layer in contact with Si and show that a combination of theory and experiment can reveal localized electronic states and the atomic structure at buried interfaces...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644652/topological-insulators-in-amorphous-systems
#11
Adhip Agarwala, Vijay B Shenoy
Much of the current understanding of topological insulators, which informs the experimental search for topological materials and systems, is based on crystalline band theory, where local electronic degrees of freedom at different crystal sites hybridize with each other in ways that produce nontrivial topology. Here we provide a novel theoretical demonstration of realizing topological phases in amorphous systems, as exemplified by a set of sites randomly located in space. We show this by constructing hopping models on such random lattices whose gapped ground states are shown to possess nontrivial topological nature (characterized by Bott indices) that manifests as quantized conductances in systems with a boundary...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644648/crossing-over-from-attractive-to-repulsive-interactions-in-a-tunneling-bosonic-josephson-junction
#12
G Spagnolli, G Semeghini, L Masi, G Ferioli, A Trenkwalder, S Coop, M Landini, L Pezzè, G Modugno, M Inguscio, A Smerzi, M Fattori
We explore the interplay between tunneling and interatomic interactions in the dynamics of a bosonic Josephson junction. We tune the scattering length of an atomic ^{39}K Bose-Einstein condensate confined in a double-well trap to investigate regimes inaccessible to other superconducting or superfluid systems. In the limit of small-amplitude oscillations, we study the transition from Rabi to plasma oscillations by crossing over from attractive to repulsive interatomic interactions. We observe a critical slowing down in the oscillation frequency by increasing the strength of an attractive interaction up to the point of a quantum phase transition...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644647/quasi-low-dimensional-electron-gas-with-one-populated-band-as-a-testing-ground-for-time-dependent-density-functional-theory-of-mesoscopic-systems
#13
Vladimir U Nazarov
We find an exact analytical solution to the exchange-only time-dependent density-functional theory (TDDFT) problem for a significant class of quasi-low-dimensional (QLD) materials: QLD electron gas with only one band filled in the direction perpendicular to the layer or wire. The theory yields the TD exchange potential as an explicit nonlocal operator of the TD spin density. The dressed interband (image states) excitation spectra of quasi-two-dimensional electron gas are obtained, while the comparison with the Kohn-Sham transitions provides insights into the qualitative and quantitative role of the many-body interactions...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644642/probing-electron-phonon-interaction-through-two-photon-interference-in-resonantly-driven-semiconductor-quantum-dots
#14
Antoine Reigue, Jake Iles-Smith, Fabian Lux, Léonard Monniello, Mathieu Bernard, Florent Margaillan, Aristide Lemaitre, Anthony Martinez, Dara P S McCutcheon, Jesper Mørk, Richard Hostein, Valia Voliotis
We investigate the temperature dependence of photon coherence properties through two-photon interference (TPI) measurements from a single quantum dot (QD) under resonant excitation. We show that the loss of indistinguishability is related only to the electron-phonon coupling and is not affected by spectral diffusion. Through these measurements and a complementary microscopic theory, we identify two independent separate decoherence processes, both of which are associated with phonons. Below 10 K, we find that the relaxation of the vibrational lattice is the dominant contribution to the loss of TPI visibility...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644633/role-of-preload-in-adhesion-of-rough-surfaces
#15
L Dorogin, A Tiwari, C Rotella, P Mangiagalli, B N J Persson
Adhesion between glass and bromobutyl and polydimethylsiloxane elastomers is investigated. We show that viscoelastic energy dissipation close to the opening (or closing) crack tip, and surface roughness, strongly affect the work of adhesion. We observe strong adhesion hysteresis and we show, in contrast to the Johnson-Kendall-Roberts theory prediction for elastic solids, that this results in a pull-off force, and effective work of adhesion to be dependent on the maximum loading force.
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644619/long-bonding-in-hngcn-nc-ng-noble-gas-molecules-an-nbo-nrt-investigation
#16
Guiqiu Zhang, Shengnan Zhang, De-Zhan Chen
Recently, Weinhold et al. put forward one new concept of σ̂-type long-bonding and applied it to the comprehension of halogen noble-gas hydrides HNgY (Ng = noble gas; Y = halogen) bonding. The present study extends this new concept into HNgX (X = CN, NC) pseudo-halogen molecules. At the B3LYP and CCSD(T) levels of theory, we perform Natural Bond Orbital (NBO) and Natural Resonance Theory (NRT) studies on the HNgX molecules and compare it with the previous results of HNgY molecules. The NBO/NRT results clearly reveal that each of the HNgX, but not the HHeCN, HNeCN and HNeNC molecules, is composed of three leading resonance structures: two ω-bonding structures H-Ng(+) :X(-), H:(-) Ng(+)-X and one long-bonded structure H^X...
June 23, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28644612/suppressing-isomerization-of-phosphine-protected-au9-cluster-by-bond-stiffening-induced-by-a-single-pd-atom-substitution
#17
Seiji Yamazoe, Shota Matsuo, Satoru Muramatsu, Shinjiro Takano, Kiyofumi Nitta, Tatsuya Tsukuda
The fluxional nature of small gold clusters has been exemplified by reversible isomerization between [Au9(PPh3)8](3+) with a crown motif (Au9(C)) and that with a butterfly motif (Au9(B)) induced by association and dissociation with compact counteranions (NO3(-), Cl(-)). However, structural isomerization was suppressed by substitution of the central Au atom of the Au9 core in [Au9(PPh3)8](3+) with a Pd atom: [PdAu8(PPh3)8](2+) with a crown motif (PdAu8(C)) did not isomerize to that with a butterfly motif (PdAu8(B)) upon association with the counteranions...
June 23, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28644583/a-slice-of-hospital-toast-a-day-keeps-the-doctors-at-bay
#18
S Martin, C Hill
Anecdotal evidence over the years has suggested that toast made in hospital, so called 'hospital toast' tastes better than toast made at home, or anywhere else for that matter. We carried out a prospective, multi-professional study to determine the views and the toast eating habits of NHS staff. Fifty members of NHS staff were surveyed across two hospital trusts. This included nursing staff, doctors from various specialties and allied health professionals. Results were overwhelming, a staggering 96% admitted to enjoying a slice of hospital toast while at work...
December 12, 2016: Irish Medical Journal
https://www.readbyqxmd.com/read/28644538/protective-factors-coping-appraisals-and-social-barriers-predict-mental-health-following-community-violence-a-prospective-test-of-social-cognitive-theory
#19
Andrew J Smith, Erika D Felix, Charles C Benight, Russell T Jones
This study tested social cognitive theory of posttraumatic adaptation in the context of mass violence, hypothesizing that pre-event protective factors (general self-efficacy and perceived social support) would reduce posttraumatic stress symptoms (PTSS) and depression severity through boosting post-event coping self-efficacy appraisals (mediator). We qualified hypotheses by predicting that post-event social support barriers would disrupt (moderate) the health-promoting indirect effects of pre-event protective factors...
June 2017: Journal of Traumatic Stress
https://www.readbyqxmd.com/read/28644492/electronic-properties-of-blue-phosphorene-graphene-and-blue-phosphorene-graphene-like-gallium-nitride-heterostructures
#20
Minglei Sun, Jyh-Pin Chou, Jin Yu, Wencheng Tang
Blue phosphorene (BlueP) is a graphene-like phosphorus nanosheet which was synthesized very recently for the first time [Nano Lett., 2016, 16, 4903-4908]. The combination of electronic properties of two different two-dimensional materials in an ultrathin van der Waals (vdW) vertical heterostructure has been proved to be an effective approach to the design of novel electronic and optoelectronic devices. Therefore, we used density functional theory to investigate the structural and electronic properties of two BlueP-based heterostructures - BlueP/graphene (BlueP/G) and BlueP/graphene-like gallium nitride (BlueP/g-GaN)...
June 23, 2017: Physical Chemistry Chemical Physics: PCCP
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