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https://www.readbyqxmd.com/read/29628527/high-abundances-of-presolar-grains-and-15-n-rich-organic-matter-in-co3-0-chondrite-dominion-range-08006
#1
Larry R Nittler, Conel M O'D Alexander, Jemma Davidson, My E I Riebe, Rhonda M Stroud, Jianhua Wang
NanoSIMS C-, N-, and O-isotopic mapping of matrix in CO3.0 chondrite Dominion Range (DOM) 08006 revealed it to have in its matrix the highest abundance of presolar O-rich grains (257 +76/-96 ppm, 2σ) of any meteorite. It also has a matrix abundance of presolar SiC of 35 (+25/-17, 2σ) ppm, similar to that seen across primitive chondrite classes. This provides additional support to bulk isotopic and petrologic evidence that DOM 08006 is the most primitive known CO meteorite. Transmission electron microscopy of five presolar silicate grains revealed one to have a composite mineralogy similar to larger amoeboid olivine aggregates and consistent with equilibrium condensation, two non-stoichiometric amorphous grains and two olivine grains, though one is identified as such solely based on its composition...
April 1, 2018: Geochimica et Cosmochimica Acta
https://www.readbyqxmd.com/read/29447065/born-criminal-differences-in-structural-functional-and-behavioural-lateralization-between-criminals-and-noncriminals
#2
Priscilla Savopoulos, Annukka K Lindell
Over 100 years ago Lombroso [(1876/2006). Criminal man. Durham: Duke University Press] proposed a biological basis for criminality. Based on inspection of criminals' skulls he theorized that an imbalance of the cerebral hemispheres was amongst 18 distinguishing features of the criminal brain. Specifically, criminals were less lateralized than noncriminals. As the advent of neuroscientific techniques makes more fine-grained inspection of differences in brain structure and function possible, we review criminals' and noncriminals' structural, functional, and behavioural lateralization to evaluate the merits of Lombroso's thesis and investigate the evidence for the biological underpinning of criminal behaviour...
February 15, 2018: Laterality
https://www.readbyqxmd.com/read/29347659/crystallization-of-finite-extensible-nonlinear-elastic-lennard-jones-coarse-grained-polymers
#3
Julien Morthomas, Claudio Fusco, Zengqiang Zhai, Olivier Lame, Michel Perez
The ability of a simple coarse-grained finite-extensible nonlinear elastic (FENE) Lennard-Jones (LJ) polymer model to be crystallized is investigated by molecular dynamics simulations. The optimal FENE Lennard-Jones parameter combinations (ratio between FENE and LJ equilibrium distances) and the optimal lattice parameters are calculated for five different perfect crystallite structures: simple tetragonal, body-centered tetragonal, body-centered orthorhombic, hexagonal primitive, and hexagonal close packed. It was found that the most energetically favorable structure is the body-centered orthorhombic...
November 2017: Physical Review. E
https://www.readbyqxmd.com/read/29300174/ionic-liquid-interface-at-an-electrode-simulations-of-electrochemical-properties-using-an-asymmetric-restricted-primitive-model
#4
Hongduo Lu, Sture Nordholm, Clifford E Woodward, Jan Forsman
We use Monte Carlo simulations of a coarse-grained model to investigate structure and electrochemical behaviours at an electrode immersed in room temperature ionic liquids (RTILs). The simple RTIL model, which we denote the asymmetric restricted primitive model (ARPM), is composed of monovalent hard-sphere ions, all of the same size, in which the charge is asymmetrically placed. Not only the hard-sphere size (d), but also the charge displacement (b), is identical for all species, i.e. the monovalent RTIL ions are fully described by only two parameters (d, b)...
February 21, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/29203657/percolative-core-formation-in-planetesimals-enabled-by-hysteresis-in-metal-connectivity
#5
Soheil Ghanbarzadeh, Marc A Hesse, Maša Prodanović
The segregation of dense core-forming melts by porous flow is a natural mechanism for core formation in early planetesimals. However, experimental observations show that texturally equilibrated metallic melt does not wet the silicate grain boundaries and tends to reside in isolated pockets that prevent percolation. Here we use pore-scale simulations to determine the minimum melt fraction required to induce porous flow, the percolation threshold. The composition of terrestrial planets suggests that typical planetesimals contain enough metal to overcome this threshold...
December 19, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28878980/the-origins-of-babytalk-smiling-teaching-or-social-convergence
#6
Marina Kalashnikova, Christopher Carignan, Denis Burnham
When addressing their young infants, parents systematically modify their speech. Such infant-directed speech (IDS) contains exaggerated vowel formants, which have been proposed to foster language development via articulation of more distinct speech sounds. Here, this assumption is rigorously tested using both acoustic and, for the first time, fine-grained articulatory measures. Mothers were recorded speaking to their infant and to another adult, and measures were taken of their acoustic vowel space, their tongue and lip movements and the length of their vocal tract...
August 2017: Royal Society Open Science
https://www.readbyqxmd.com/read/28740862/giant-convecting-mud-balls-of-the-early-solar-system
#7
Philip A Bland, Bryan J Travis
Carbonaceous asteroids may have been the precursors to the terrestrial planets, yet despite their importance, numerous attempts to model their early solar system geological history have not converged on a solution. The assumption has been that hydrothermal alteration was occurring in rocky asteroids with material properties similar to meteorites. However, these bodies would have accreted as a high-porosity aggregate of igneous clasts (chondrules) and fine-grained primordial dust, with ice filling much of the pore space...
July 2017: Science Advances
https://www.readbyqxmd.com/read/28629131/a-hybrid-scheme-for-fine-grained-search-and-access-authorization-in-fog-computing-environment
#8
Min Xiao, Jing Zhou, Xuejiao Liu, Mingda Jiang
In the fog computing environment, the encrypted sensitive data may be transferred to multiple fog nodes on the edge of a network for low latency; thus, fog nodes need to implement a search over encrypted data as a cloud server. Since the fog nodes tend to provide service for IoT applications often running on resource-constrained end devices, it is necessary to design lightweight solutions. At present, there is little research on this issue. In this paper, we propose a fine-grained owner-forced data search and access authorization scheme spanning user-fog-cloud for resource constrained end users...
June 17, 2017: Sensors
https://www.readbyqxmd.com/read/28626610/tiny-pollen-grains-first-evidence-of-saururaceae-from-the-late-cretaceous-of-western-north-america
#9
Friðgeir Grímsson, Guido W Grimm, Reinhard Zetter
BACKGROUND: The Saururaceae, a very small family of Piperales comprising only six species in four genera, have a relatively scanty fossil record outside of Europe. The phylogenetic relationships of the four genera to each other are resolved, with the type genus Saururus occurring in both eastern North America and East Asia. No extant species occurs in western Eurasia. The most exceptional find so far has been an inflorescence with in-situ pollen, Saururus tuckerae S.Y.Sm. & Stockey from Eocene of North America with strong affinities to extant species of Saururus...
2017: PeerJ
https://www.readbyqxmd.com/read/28599118/sensory-metrics-of-neuromechanical-trust
#10
William Softky, Criscillia Benford
Today digital sources supply a historically unprecedented component of human sensorimotor data, the consumption of which is correlated with poorly understood maladies such as Internet addiction disorder and Internet gaming disorder. Because both natural and digital sensorimotor data share common mathematical descriptions, one can quantify our informational sensorimotor needs using the signal processing metrics of entropy, noise, dimensionality, continuity, latency, and bandwidth. Such metrics describe in neutral terms the informational diet human brains require to self-calibrate, allowing individuals to maintain trusting relationships...
September 2017: Neural Computation
https://www.readbyqxmd.com/read/28554979/cometary-dust-the-diversity-of-primitive-refractory-grains
#11
REVIEW
D H Wooden, H A Ishii, M E Zolensky
Comet dust is primitive and shows significant diversity. Our knowledge of the properties of primitive cometary particles has expanded significantly through microscale investigations of cosmic dust samples (anhydrous interplanetary dust particles (IDPs), chondritic porous (CP) IDPs and UltraCarbonaceous Antarctic micrometeorites, Stardust and Rosetta), as well as through remote sensing (Spitzer IR spectroscopy). Comet dust are aggregate particles of materials unequilibrated at submicrometre scales. We discuss the properties and processes experienced by primitive matter in comets...
July 13, 2017: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/28319376/anomalous-protein-protein-interactions-in-multivalent-salt-solution
#12
Coralie Pasquier, Mario Vazdar, Jan Forsman, Pavel Jungwirth, Mikael Lund
The stability of aqueous protein solutions is strongly affected by multivalent ions, which induce ion-ion correlations beyond the scope of classical mean-field theory. Using all-atom molecular dynamics (MD) and coarse grained Monte Carlo (MC) simulations, we investigate the interaction between a pair of protein molecules in 3:1 electrolyte solution. In agreement with available experimental findings of "reentrant protein condensation", we observe an anomalous trend in the protein-protein potential of mean force with increasing electrolyte concentration in the order: (i) double-layer repulsion, (ii) ion-ion correlation attraction, (iii) overcharge repulsion, and in excess of 1:1 salt, (iv) non Coulombic attraction...
March 31, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/27696175/m-2-abks-attribute-based-multi-keyword-search-over-encrypted-personal-health-records-in-multi-owner-setting
#13
Yinbin Miao, Jianfeng Ma, Ximeng Liu, Fushan Wei, Zhiquan Liu, Xu An Wang
Online personal health record (PHR) is more inclined to shift data storage and search operations to cloud server so as to enjoy the elastic resources and lessen computational burden in cloud storage. As multiple patients' data is always stored in the cloud server simultaneously, it is a challenge to guarantee the confidentiality of PHR data and allow data users to search encrypted data in an efficient and privacy-preserving way. To this end, we design a secure cryptographic primitive called as attribute-based multi-keyword search over encrypted personal health records in multi-owner setting to support both fine-grained access control and multi-keyword search via Ciphertext-Policy Attribute-Based Encryption...
November 2016: Journal of Medical Systems
https://www.readbyqxmd.com/read/27629644/primitive-solar-system-materials-and-earth-share-a-common-initial-142-nd-abundance
#14
LETTER
A Bouvier, M Boyet
The early evolution of planetesimals and planets can be constrained using variations in the abundance of neodymium-142 ((142)Nd), which arise from the initial distribution of (142)Nd within the protoplanetary disk and the radioactive decay of the short-lived samarium-146 isotope ((146)Sm). The apparent offset in (142)Nd abundance found previously between chondritic meteorites and Earth has been interpreted either as a possible consequence of nucleosynthetic variations within the protoplanetary disk or as a function of the differentiation of Earth very early in its history...
September 15, 2016: Nature
https://www.readbyqxmd.com/read/27610313/alkali-basalts-and-enclosed-ultramafic-xenoliths-near-ushuaia-tierra-del-fuego-argentina
#15
Rogelio Daniel Acevedo
At the southernmost part of Tierra del Fuego a few outcrops and erratic boulders of alkali basaltic rocks with ultramafic enclaves have been studied. Alkali basalt plugs or pipes hitherto identified are scarce, and host rocks are constituted by slates that belong to Mesozoic deposition. The petrography, texture and composition of the basalt and xenoliths were investigated by petrographic microscope and electron microprobe analysis. Xenocrysts of amphibole and alkali feldspar, phenocrysts of nepheline, olivine, spinel, phlogopite and Fe-Ti minerals (10 %) and a diversity of xenoliths, mainly lherzolitic, pyroxenite and wehrlitic nodules (15 %), but also from metamorphic rocks provenance, are contained in the basalt groundmass (75 %)...
2016: SpringerPlus
https://www.readbyqxmd.com/read/27547207/patterns-of-ros-accumulation-in-the-stigmas-of-angiosperms-and-visions-into-their-multi-functionality-in-plant-reproduction
#16
Adoración Zafra, Juan D Rejón, Simon J Hiscock, Juan de Dios Alché
Accumulation of reactive oxygen species (ROS) in the stigma of several plant species has been investigated. Four developmental stages (unopened flower buds, recently opened flowers, dehiscent anthers, and flowers after fertilization) were analyzed by confocal laser scanning microscopy using the ROS-specific probe DCFH2-DA. In all plants scrutinized, the presence of ROS in the stigmas was detected at higher levels during those developmental phases considered "receptive" to pollen interaction. In addition, these molecules were also present at early (unopened flower) or later (post-fertilization) stages, by following differential patterns depending on the different species...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27544120/effect-of-intrinsic-curvature-and-edge-tension-on-the-stability-of-binary-mixed-membrane-three-junctions
#17
Jasmine M Gardner, Markus Deserno, Cameron F Abrams
We use a combination of coarse-grained molecular dynamics simulations and theoretical modeling to examine three-junctions in mixed lipid bilayer membranes. These junctions are localized defect lines in which three bilayers merge in such a way that each bilayer shares one monolayer with one of the other two bilayers. The resulting local morphology is non-lamellar, resembling the threefold symmetric defect lines in inverse hexagonal phases, but it regularly occurs during membrane fission and fusion events. We realize a system of junctions by setting up a honeycomb lattice, which in its primitive cell contains two hexagons and four three-line junctions, permitting us to study their stability as well as their line tension...
August 21, 2016: Journal of Chemical Physics
https://www.readbyqxmd.com/read/27390389/bigdebug-debugging-primitives-for-interactive-big-data-processing-in-spark
#18
Muhammad Ali Gulzar, Matteo Interlandi, Seunghyun Yoo, Sai Deep Tetali, Tyson Condie, Todd Millstein, Miryung Kim
Developers use cloud computing platforms to process a large quantity of data in parallel when developing big data analytics. Debugging the massive parallel computations that run in today's data-centers is time consuming and error-prone. To address this challenge, we design a set of interactive, real-time debugging primitives for big data processing in Apache Spark, the next generation data-intensive scalable cloud computing platform. This requires re-thinking the notion of step-through debugging in a traditional debugger such as gdb, because pausing the entire computation across distributed worker nodes causes significant delay and naively inspecting millions of records using a watchpoint is too time consuming for an end user...
May 2016: Proceedings of International Conference on Software Engineering. International Conference on Software Engineering
https://www.readbyqxmd.com/read/27378100/self-assembly-behaviours-of-primitive-and-modern-lipid-membrane-solutions-a-coarse-grained-molecular-simulation-study
#19
Noriyoshi Arai, Yuki Yoshimoto, Kenji Yasuoka, Toshikazu Ebisuzaki
Researchers have studied the origin of life and the process of evolution on early Earth for decades. However, we lack a comprehensive understanding of biogenesis, because there are many stages in the formation and growth of the first cell. We investigate the self-replication processes of coacervate protocells using computer simulations of single-chain lipid and phospholipid aqueous mixtures. Based on a morphological phase diagram, we develop a model of prebiotic self-replication driven by only environmental factors (i...
July 28, 2016: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/27147197/the-efficiency-of-driving-chemical-reactions-by-a-physical-non-equilibrium-is-kinetically-controlled
#20
Tobias Göppel, Vladimir V Palyulin, Ulrich Gerland
An out-of-equilibrium physical environment can drive chemical reactions into thermodynamically unfavorable regimes. Under prebiotic conditions such a coupling between physical and chemical non-equilibria may have enabled the spontaneous emergence of primitive evolutionary processes. Here, we study the coupling efficiency within a theoretical model that is inspired by recent laboratory experiments, but focuses on generic effects arising whenever reactant and product molecules have different transport coefficients in a flow-through system...
July 27, 2016: Physical Chemistry Chemical Physics: PCCP
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