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Developmental divergence: motor trajectories in children with fragile X syndrome with and without co-occurring autism.
BackgroundAutism spectrum disorder (ASD) is highly prevalent in fragile X syndrome (FXS), affecting 50-70% of males. Motor impairments are a shared feature across autism and FXS that may help to better characterize autism in FXS. As motor skills provide a critical foundation for various language, cognitive, and social outcomes, they may serve an important mechanistic role for autism in FXS. As such, this study aimed to identify differences in motor trajectories across direct assessment and parent-report measures of fine and gross motor development between FXS with and without autism, and typical development, while controlling for cognitive functioning.MethodsThis prospective longitudinal study included 42 children with FXS, 24 of whom also had ASD (FXS + ASD), as well as 40 typically developing children. The Mullen Scales of Early Learning provided a direct measure of fine and gross motor skills, and the Vineland Adaptive Behavior Scales provided a measure of parent-reported fine and gross motor skills. Random slopes and random intercepts multilevel models were tested to determine divergence in developmental motor trajectories between groups when controlling for cognitive level.ResultsModel results indicated the children with FXS + ASD diverged from TD children by 9-months on all measures of gross and fine motor skills, even when controlling for cognitive level. Results also indicated an early divergence in motor trajectories of fine and gross motor skills between the FXS + ASD and FXS groups when controlling for cognitive level. This divergence was statistically significant by 18 months, with the FXS + ASD showing decelerated growth in motor skills across direct observation and parent-report measures.ConclusionsThis study is the first to examine longitudinal trends in motor development in children with FXS with and without comorbid ASD using both direct assessment and parent-report measures of fine and gross motor. Furthermore, it is among the first to account for nonverbal cognitive delays, a step towards elucidating the isolated role of motor impairments in FXS with and without ASD. Findings underscore the role of motor impairments as a possible signal representing greater underlying genetic liability, or as a potential catalyst or consequence, of co-occurring autism in FXS
Grasping Force Prediction for Underactuated Multi-Fingered Hand by Using Artificial Neural Network
In this paper, the feedforward neural network with Levenberg-Marquardt backpropagation training algorithm is used to predict the grasping forces according to the multisensory signals as training samples for specific design of underactuated multifingered hand to avoid the complexity of calculating the inverse kinematics which is appeared through the dynamic modeling of the robotic hand and preparing this network to be used as part of a control system.Keywords: Grasping force, underactuated, prediction, Neural networ
Defect-unbinding transitions and inherent structures in two dimensions
We present a large-scale (36000-particle) computational study of the
"inherent structures" (IS) associated with equilibrium, two-dimensional,
one-component Lennard-Jones systems. Our results provide strong support both
for the inherent-structures theory of classical fluids, and for the KTHNY
theory of two-stage melting in two dimensions. This support comes from the
observation of three qualitatively distinct "phases" of inherent structures: a
crystal, a "hexatic glass", and a "liquid glass". We also directly observe, in
the IS, analogs of the two defect-unbinding transitions (respectively, of
dislocations, and disclinations) believed to mediate the two equilibrium phase
transitions. Each transition shows up in the inherent structures---although the
free disclinations in the "liquid glass" are embedded in a percolating network
of grain boundaries. The bond-orientational correlation functions of the
inherent structures show the same progressive loss of order as do the three
equilibrium phases: long-range to quasi-long-range to short-range.Comment: RevTeX, 8 pages, 15 figure
Management of Impacts of Longwall Mining under Urban Areas
Current and proposed expansions to existing underground coal mines are occurring in closer proximity to and directly beneath urban areas. The density of built infrastructure potentially impacted by longwall mining is substantially increased in urban areas when compared with mining beneath rural areas. Management of the impacts of longwall mining in such areas requires extensive consultation with the affected community, including education and management of communities’ expectations regarding what could be expected during and after the mining period. Approaches undertaken by Tahmoor Colliery to manage the potential impacts of mining under the township of Tahmoor are discussed. A summary of impacts that have occurred as a result of mining the first two longwalls are outlined, which are part of a series of eight longwalls that the Colliery plans to mine beneath this town. The experience gained at Tahmoor illustrates that longwall mining beneath urban areas is sustainable and can be successfully managed to mitigate the impacts on surface developments
EFFECT OF STARVATION ON THERMOELASTOHYDRODYNAMIC LUBRICATION OF ROLLING / SLIDING CONTACT
A complete numerical solution of thermal compressible elastohydrodynamic lubrication of rolling /
sliding contact was achieved to determine the effect of inlet boundary condition on the film shape,
film pressure, and film temperature in an elastohydrodynamic line contact problem.
The direct iterative technique is used to solve the simultaneous system of Reynolds, ,elasticity , and
energy equations for different locations of inlet oil fed . The effect of various load, speed , and slip
conditions have been investigated . the results indicate that the effects of starvation are an increase
of oil film temperature and decrease in oil film thickness so that the temperature effect are
significant and can not be neglected
Intramolecular hydrogen bond activation for kinetic resolution of furanone derivatives by an organocatalyzed [3+2] asymmetric cycloaddition
Herein, a formal highly enantioselective organocatalyzed [3+2] cycloaddition of furanone derivatives and azomethine ylides is presented. The success of this reaction resides in an intramolecular hydrogen bond activation through an o-hydroxy group at aromatic ring of the imine, allowing the formation of highly multifunctional bicyclic adducts with five stereogenic centers in a stereocontrolled manner. Furthermore, the reaction is paired to a highly efficient kinetic resolution of butenolides, achieving selectivity factors above 200. Using this methodology, furan-2(5H)-ones as well as furo[3,4-c]pyrrolidinones were obtained with high enantioselectivities. Quantum chemistry calculations reveal the crucial role of hydrogen bond formed between the catalyst donor-units and the two reagents, which modify their arrangement and promote effective facial discrimination resulting in a highly selective kinetic resolution. In addition, further applicability of the kinetic resolution process is shownPID2019-110091GB-I00, PID2021-122299NB-I00, TED2021-130470B-I00, TED2021-129999B-C32, “Comunidad de Madrid” for European Structural Funds (S2018/NMT-4367) and (Y2020/NMT6469), CEX2018-000805-
Universality in the Screening Cloud of Dislocations Surrounding a Disclination
A detailed analytical and numerical analysis for the dislocation cloud
surrounding a disclination is presented. The analytical results show that the
combined system behaves as a single disclination with an effective fractional
charge which can be computed from the properties of the grain boundaries
forming the dislocation cloud. Expressions are also given when the crystal is
subjected to an external two-dimensional pressure. The analytical results are
generalized to a scaling form for the energy which up to core energies is given
by the Young modulus of the crystal times a universal function. The accuracy of
the universality hypothesis is numerically checked to high accuracy. The
numerical approach, based on a generalization from previous work by S. Seung
and D.R. Nelson ({\em Phys. Rev A 38:1005 (1988)}), is interesting on its own
and allows to compute the energy for an {\em arbitrary} distribution of
defects, on an {\em arbitrary geometry} with an arbitrary elastic {\em energy}
with very minor additional computational effort. Some implications for recent
experimental, computational and theoretical work are also discussed.Comment: 35 pages, 21 eps file
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