Terms Of Intrinsic Properties Research Articles

Local sleep spindles in the human thalamus.

Sleep spindles have recently been shown to occur not only across multiple neocortical regions but also locally in restricted cortical areas. Here we show that local spindles are indeed present in the human posterior thalamus. Thalamic local spindles had lower spectral power than non-local ones. While non-local thalamic spindles had equal local and non-local cortical counterparts, local thalamic spindles had significantly more local cortical counterparts (i.e. occurring in a single cortical site). The preferential association of local thalamic and cortical spindles supports the notion of thalamocortical loops functioning in a modular way. Sleep spindles are believed to subserve many sleep-related functions, from memory consolidation to cortical development. Recent data using intracerebral recordings in humans have shown that they occur across multiple neocortical regions but may also be spatially restricted to specific brain areas (local spindles). The aim of this study was to characterize spindles at the level of the human posterior thalamus, with the hypothesis that, besides the global thalamic spindling activity usually observed, local spindles could also be present in the thalamus. Using intracranial, time-frequency EEG recordings in 17 epileptic patients, we assessed the distribution of thalamic spindles during natural sleep stages N2 and N3 in six thalamic nuclei. Local spindles (i.e. spindles present in a single pair of recording contacts) were observed in all the thalamic regions explored, and compared with non-local spindles in terms of intrinsic properties and cortical counterparts. Thalamic local and non-local spindles did not differ in density, frequency or duration, but local spindles had lower spectral power than non-local ones. Each thalamic spindle had a cortical counterpart. While non-local thalamic spindles had equal cortical local and non-local counterparts, local thalamic spindles had significantly more local cortical counterparts (i.e. occurring in a single cortical site). The preferential association of local thalamic and cortical spindles supports the notion of thalamocortical loops functioning in a modular way.

PyFrag 2019-Automating the exploration and analysis of reaction mechanisms.

We present a substantial update to the PyFrag 2008 program, which was originally designed to perform a fragment‐based activation strain analysis along a provided potential energy surface. The original PyFrag 2008 workflow facilitated the characterization of reaction mechanisms in terms of the intrinsic properties, such as strain and interaction, of the reactants. The new PyFrag 2019 program has automated and reduced the time‐consuming and laborious task of setting up, running, analyzing, and visualizing computational data from reaction mechanism studies to a single job. PyFrag 2019 resolves three main challenges associated with the automated computational exploration of reaction mechanisms: it (1) computes the reaction path by carrying out multiple parallel calculations using initial coordinates provided by the user; (2) monitors the entire workflow process; and (3) tabulates and visualizes the final data in a clear way. The activation strain and canonical energy decomposition results that are generated relate the characteristics of the reaction profile in terms of intrinsic properties (strain, interaction, orbital overlaps, orbital energies, populations) of the reactant species. © 2019 The Authors. Journal of Computational Chemistry published by Wiley Periodicals, Inc.

On primeness of general skew inverse Laurent series ring

ABSTRACTEver since the introduction, skew inverse Laurent series rings have kept growing in importance, as researchers characterized their properties (such as Noetherianness, Armendarizness, McCoyness, etc.) in terms of intrinsic properties of the base ring and studied their relations with other fields of mathematics, as for example quantum mechanics theory. The goal of our paper is to study the primeness and semiprimeness of general skew inverse Laurent series rings R((x−1;σ,δ)), where R is an associative ring equipped with an automorphism σ and a σ-derivation δ.

The feasibility of incorporating cellulose micro/nanofibers in papermaking processes: the relevance of enzymatic hydrolysis

Cellulose nanofiber (CNF) is becoming a topic of great interest among the industrial and academic communities, mainly due to their potential applications in very well-differentiated industrial sectors. Among this wide range of applications, papermaking is one of the most accepted and studied. However, it is widely known that the papermaking sector is forced to compete in markets where products do not have huge added value and production margins are very low. Therefore, papermakers are constantly looking for new technologies that balance efficiency and production costs. In line with this, the present work attempts to assay the enzymatic hydrolysis of cellulose fibers to obtain CNFs. Accordingly, pH, pulp consistency, treatment time, enzyme dosage and temperature were varied to find a combination of parameters that could lead to highly efficient CNF in terms of the mechanical properties of paper enhancement and production costs. For this, CNFs were applied to unrefined and refined bleached kraft pulps and their properties were assessed. The obtained results demonstrated that it is possible to obtain highly efficient CNFs from bleached pulp at affordable costs for papermakers. Moreover, it was found that the treatment time has a key role during the production of this CNF but at low enzyme dosages since the obtained results, in terms of intrinsic properties and reinforcing potential, for high enzyme charges did not vary significantly as time was increased. In sum, the present work offers a cost-efficient solution for the application of CNF in the production of paper from bleached pulp as well as a promising alternative to those conventional processes from a technical point of view.

Preventing Electrical Shorts in Parallel-Plate Capacitors with Single-Printed Dielectric Layer

Double-printing of dielectric layers is commonly used to prevent electrical shorts in parallel-plate capacitors, but this increases the thickness of the dielectric layer and diminishes the corresponding capacitance. Double-printing also complicates the production process and increases production costs. In this paper, it is demonstrated that capacitors with single-printed dielectric layers are without shorts if the layer is completely polymerized. Therefore, electrical shorts could also be related to the state of polymerization in a defect-free dielectric layer. To demonstrate this, the electrical functionality of capacitors with single-printed dielectric layers was studied in terms of intrinsic properties of the ultraviolet (UV) curable dielectric layer, which were varied according to the curing energy. The chemical structure of the cured layer was analyzed with infrared spectroscopy to obtain the appearance of polymerizable groups and crosslinks within the polymer structure. Differential scanning calorimetry was used to measure the glass transition temperature of the dielectric material. It increases rapidly with UV curing until the polymerization is completed, whereas a small increase with further curing confirms crosslinking of the polymer. The influence of structuring effects within a dielectric layer in the presence of electrical shorts between electrodes is discussed. This research confirms that a completely polymerized layer forms a barrier to leakage and helps to prevent the formation of conductive paths between electrodes. Therefore, a connection between the structure of polymerized layer and its electrical properties is highly reasonable.

Reconstructing functions from random samples

From a sufficiently large point sample lying on a compact Riemannian submanifold of Euclidean space, one can construct a simplicial complex which is homotopy-equivalent to that manifold with high confidence. We describe a corresponding result for a Lipschitz-continuous function between two such manifolds. That is, we outline the construction of a simplicial map which recovers the induced maps on homotopy and homology groups with high confidence using only finite sampled data from the domain and range, as well as knowledge of the image of every point sampled from the domain. We provide explicit bounds on the size of the point samples required for such reconstruction in terms of intrinsic properties of the domain, the co-domain and the function. This reconstruction is robust to certain types of bounded sampling and evaluation noise.

CLASSICAL BEHAVIOR OF TWO-DIMENSIONAL LIQUID 3He NEAR A QUANTUM CRITICAL POINT

Non-Fermi-liquid (NFL) behavior of the specific heat C(T) of two-dimensional (2D) liquid 3 He , first uncovered in measurements almost 20 years ago, is explained in terms of intrinsic properties of this system that emerge when its density rises and the liquid becomes strongly correlated. The occurrence of a T-independent β term in C(T) is attributed to satisfaction of the conditions for Dulong–Petit behavior by the boson part of the free energy. This unexpected classicality stems from softening of the transverse zero-sound mode (TZSM) in the density region where the anomaly in C(T), associated with a quantum critical point (QCP), is observed.

Room temperature ferromagnetism in combustion reaction prepared iron-doped zinc oxide nanoparticles

We present a study of the structural and magnetic properties of Zn1−xFexO (0.00≤x≤0.09) nanoparticles prepared by a combustion reaction method. X-ray diffraction patterns of all samples showed sharp and intensive peaks of hexagonal wurtzite structure of ZnO without any evidence of spurious crystalline phases in all samples. The magnetic properties were measured by using a vibrating sample magnetometer. Hysteresis loop indicated that all samples are ferromagnetic at room temperature and the Curie temperature increased with increasing iron content. Room temperature ferromagnetism can be explained in terms of intrinsic properties and the presence of defects in Fe- doped ZnO nanoparticles.

Textons and the Propagation of Space in Acousmatic Music

The concepts introduced by Smalley in the context of space-form (2007) have firmly put acousmatic music on a discourse of spatial exploration, holding much potential for the developing of aesthetics in new directions. This article approaches space from the low level of musical structure, with a multi-dimensional attitude to space-form, exploring spatial texture, a concept introduced by Smalley to describe the temporal formations of space in spectromorphology (1997). Spatial articulation is investigated in the context of granular-oriented textures, proposing a micro-spatial, perceptual morphology – the texton – as an aesthetic approach to acousmatic music. This follows Albert Bregman's speculation regarding equivalents to visual perception in texture, where the theory of textons was first developed by the neuroscientist Béla Julesz.The article discusses acousmatic textons, in terms of intrinsic properties, the way they propagate in time, and how they organise in distributions to form spatial textures. The emergent macroscopic qualities of textonal formations are also reflected upon in the introduction of a group of textural states, where source-bonded spaces and abstract musical thinking coalesce.

Improving silica matrices for encapsulation of Escherichiacoli using osmoprotectors

The development of sol–gel based processes for the encapsulation of living cells is a challenging task where the host material must be optimized both in terms of intrinsic properties and impact on cell viability. Here, the mechanical stability of silica hosts obtained via a mixed aqueous route based on sodium silicate–silica nanoparticle mixtures could be improved by increasing the relative content of molecular precursors over colloidal silica. The specific surface area, pore volume and diffusion properties of the host were also modified. Moreover, this resulted in an increase in the ionic strength, inducing high osmolarity that is detrimental to encapsulated Escherichia coli bacteria. Glycine betaine, a well-known E. coli osmoprotector, could be successfully used as an additive to the sol–gel formulation to limit this osmotic stress. Compared to the previously studied glycerol additive, glycine betaine was found more efficient to preserve the bacterial viability. Moreover, this efficiency was obtained with much lower amounts of glycine betaine, whose addition has therefore no detrimental impact on the silica host structure. These data provide new information about the different cellular stresses resulting from the sol–gel encapsulation process and demonstrate the importance of combining chemical and biological approaches to design more robust functional “living” materials.

Pour une sémiogenèse du nom

P. Cadiot et F. Némo : Pour une sémiogenèse du nom Lexical signification is often conceived, at least partially, in terms of a description or, in our terminology, in terms of intrinsic properties (IP). In this article we explore an opposite hypothesis that words (most notably nouns) invoke directly those types of relations : 1 . which a given word allows the loculor to establish with various referents. 2 . which these referents have (or arc perceived as having) with their environment. The meaning itself of nouns must be identified with these relations or extrinsic properties (EP). In this way, polysemic, metonymic and metaphoric usages shed their marginal status, becoming the basis of a lexical signification which purely denominative usages conversely tend to obscure.

Box Splines with Rational Directions and Linear Diophantine Equations

A necessary and sufficient condition for the linear independence of integer translates of Box splines with rational directions is presented in terms of intrinsic properties of the defining matrices. We also give a necessary and sufficient condition for the space of linear dependence relations to be finite dimensional. A method to compute the approximation order of these Box spline spaces is obtained. All these conditions can be tested by finite steps of computations based on elementary properties of the matrices. The method of proofs is from linear diophantine equations.

Ab initio studies of hydrogen-bonded complexes between uracil and HCl

Ab initio SCF calculations were performed to investigate the hydrogen-bonding characteristics of the two carbonyl groups of the uracil molecule. The calculated interaction energy of the uracil-HCl complexes shows a strong basis-set dependence and provides no evidence for a significant difference between the two carbonyl groups in terms of intrinsic properties.

Novel type of emissive flat panel display: the matrixed cold-cathode microtip fluorescent display

A new principle applicable to the design of flat panel displays is proposed, which combines two techniques already developed independently: electronic field emission of microtips fabricated with advanced microelectronic technology, and low-voltage cathodoluminescent (front luminous) layers. The resulting structure, called the microtip fluorescent display (MFD), is briefly analysed in terms of intrinsic properties and main technological and operational characteristics.

Hydrogen bonding of the carbonyl groups of uridine nucleosides

AbstractMolecular‐orbital calculations are used to compare the hydrogen‐bonding characteristics of the two carbonyl groups of uridine nucleosides. Various numbers of water molecules are allowed to interact with uracil. The hydrogen‐bond energies and the effects of these bonds on the electronic structure of uracil provide no evidence of a significant difference between the two carbonyls in terms of intrinsic properties. Calculations are also performed upon MMU, a derivative of the uridine nucleoside and a close analog of a system studied previously by nmr measurements. Energy minima are located on the conformational energy surface. The calculated anti‐gg global minimum is quite similar to the x‐ray structure. Electronic parameters examined in the various minima, as well as in hydrated complexes of MMU, again indicate no significant chemical differences between the two carbonyls. The theoretical data offer an explanation of the observed differences in shift of the two carbonyl 17O resonance signals when an aprotic solvent is replaced by water. Whereas the two carbonyls are found to be chemically similar, the observed difference in behaviour is attributed to steric factors. The lesser accessibility of the C2 carbonyl to solvation allows a smaller number of hydrogen bonds with water and hence a reduced shift when the solvent is changed.