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https://www.readbyqxmd.com/read/27933283/neonatal-diagnostics-toward-dynamic-growth-charts-of-neuromotor-control
#1
Elizabeth B Torres, Beth Smith, Sejal Mistry, Maria Brincker, Caroline Whyatt
The current rise of neurodevelopmental disorders poses a critical need to detect risk early in order to rapidly intervene. One of the tools pediatricians use to track development is the standard growth chart. The growth charts are somewhat limited in predicting possible neurodevelopmental issues. They rely on linear models and assumptions of normality for physical growth data - obscuring key statistical information about possible neurodevelopmental risk in growth data that actually has accelerated, non-linear rates-of-change and variability encompassing skewed distributions...
2016: Frontiers in Pediatrics
https://www.readbyqxmd.com/read/27925728/traveling-majorana-solitons-in-a-low-dimensional-spin-orbit-coupled-fermi-superfluid
#2
Peng Zou, Joachim Brand, Xia-Ji Liu, Hui Hu
We investigate traveling solitons of a one- or two-dimensional spin-orbit-coupled Fermi superfluid in both topologically trivial and nontrivial regimes by solving the static and time-dependent Bogoliubov-de Gennes equations. We find a critical velocity v_{h} for traveling solitons that is much smaller than the value predicted using the Landau criterion due to spin-orbit coupling. Above v_{h}, our time-dependent simulations in harmonic traps indicate that traveling solitons decay by radiating sound waves. In the topological phase, we predict the existence of peculiar Majorana solitons, which host two Majorana fermions and feature a phase jump of π across the soliton, irrespective of the velocity of travel...
November 25, 2016: Physical Review Letters
https://www.readbyqxmd.com/read/27922660/combined-vision-and-wearable-sensors-based-system-for-movement-analysis-in-rehabilitation
#3
Sofija Spasojević, Tihomir V Ilić, Slađan Milanović, Veljko Potkonjak, Aleksandar Rodić, José Santos-Victor
BACKGROUND: Traditional rehabilitation sessions are often a slow, tedious, disempowering and non-motivational process, supported by clinical assessment tools, i.e. evaluation scales that are prone to subjective rating and imprecise interpretation of patient's performance. Poor patient motivation and insufficient accuracy are thus critical factors that can be improved by new sensing / processing technologies. OBJECTIVES: We aim to develop a portable and affordable system, suitable for home rehabilitation, which combines vision-based and wearable sensors...
December 6, 2016: Methods of Information in Medicine
https://www.readbyqxmd.com/read/27919485/the-required-coefficient-of-friction-for-evaluating-gait-alterations-in-people-with-multiple-sclerosis-during-gait
#4
Ilaria Pacifici, Manuela Galli, Ana Francisca Rozin Kleiner, Federica Corona, Giancarlo Coghe, Elisabetta Marongiu, Andrea Loi, Antonio Crisafulli, Eleonora Cocco, Maria Giovanna Marrosu, Massimiliano Pau
BACKGROUND: Required Coefficient of Friction (RCOF) is one of the most critical gait parameters associated to the occurrence of slipping in individuals affected by neurological disorders characterized by balance impairments. This study aims to calculate RCOF in people with Multiple Sclerosis (MS) on the basis of three-dimensional Gait Analysis (GA) data. METHODS: This study enrolls 22 people with MS (pwMS) who were characterized by an Expanded Disability Status Score in the range 1...
November 2016: Multiple Sclerosis and related Disorders
https://www.readbyqxmd.com/read/27915224/the-relative-and-absolute-reliability-of-center-of-pressure-trajectory-during-gait-initiation-in-older-adults
#5
Roya Khanmohammadi, Saeed Talebian, Mohammad Reza Hadian, Gholamreza Olyaei, Hossein Bagheri
It has been thought that for scientific acceptance of a parameter, its psychometric properties such as reliability, validity and responsiveness have critical roles. Therefore, this study was conducted to estimate how many trials are required to obtain a reliable center of pressure (COP) parameter during gait initiation (GI) and to investigate the effect of number of trials on the relative and absolute reliability. Twenty older adults participated in the study. Subjects began stepping over the force platform in response to an auditory stimulus...
November 28, 2016: Gait & Posture
https://www.readbyqxmd.com/read/27909001/synaptic-phospholipid-signaling-modulates-axon-outgrowth-via-glutamate-dependent-ca2-mediated-molecular-pathways
#6
Johannes Vogt, Sergei Kirischuk, Petr Unichenko, Leslie Schlüter, Assunta Pelosi, Heiko Endle, Jenq-Wei Yang, Nikolai Schmarowski, Jin Cheng, Carine Thalman, Ulf Strauss, Alexey Prokudin, B Suman Bharati, Junken Aoki, Jerold Chun, Beat Lutz, Heiko J Luhmann, Robert Nitsch
Altered synaptic bioactive lipid signaling has been recently shown to augment neuronal excitation in the hippocampus of adult animals by activation of presynaptic LPA2-receptors leading to increased presynaptic glutamate release. Here, we show that this results in higher postsynaptic Ca(2+) levels and in premature onset of spontaneous neuronal activity in the developing entorhinal cortex. Interestingly, increased synchronized neuronal activity led to reduced axon growth velocity of entorhinal neurons which project via the perforant path to the hippocampus...
November 30, 2016: Cerebral Cortex
https://www.readbyqxmd.com/read/27898419/high-pulse-wave-velocity-defines-a-very-high-cardiovascular-risk-cohort-of-dialysis-patients-under-age-60
#7
João Pedro Ferreira, Nicolas Girerd, Bruno Pannier, Patrick Rossignol, Gerard M London
BACKGROUND: Patients with end-stage renal disease (ESRD) are at a high risk of cardiovascular mortality (CVM). In patients with ESRD, arterial stiffness increases at an earlier age when compared to the general population and this contributes to the overall risk of cardiovascular mortality. The main objective of this study was to clarify the interplay between age and cardiovascular alterations in ESRD. METHODS: Prospective, observational cohort study initiated in April 1987 until the end of 1998 with events recorded until the end of the year 2000 at the F...
November 30, 2016: American Journal of Nephrology
https://www.readbyqxmd.com/read/27895596/reciprocal-modulation-of-ik1-ina-extends-excitability-in-cardiac-ventricular-cells
#8
Anthony Varghese
The inwardly rectifying potassium current (IK1) and the fast inward sodium current (INa) are reciprocally modulated in mammalian ventricular myocytes. An increase in the expression of channels responsible for one of these two currents results in a corresponding increase in expression of the other. These currents are critical in the propagation of action potentials (AP) during the normal functioning of the heart. This study identifies a physiological role for IK1-INa reciprocal modulation in ventricular fiber activation thresholds and conduction...
2016: Frontiers in Physiology
https://www.readbyqxmd.com/read/27890536/estimation-of-the-center-of-rotation-using-wearable-magneto-inertial-sensors
#9
M Crabolu, D Pani, L Raffo, A Cereatti
Determining the center of rotation (CoR) of joints is fundamental to the field of human movement analysis. CoR can be determined using a magneto-inertial measurement unit (MIMU) using a functional approach requiring a calibration exercise. We systematically investigated the influence of different experimental conditions that can affect precision and accuracy while estimating the CoR, such as (a) angular joint velocity, (b) distance between the MIMU and the CoR, (c) type of the joint motion implemented, (d) amplitude of the angular range of motion, (e) model of the MIMU used for data recording, (f) amplitude of additive noise on inertial signals, and (g) amplitude of the errors in the MIMU orientation...
November 16, 2016: Journal of Biomechanics
https://www.readbyqxmd.com/read/27886327/in-situ-tem-observation-on-the-interface-type-resistive-switching-by-electrochemical-redox-reactions-at-a-tin-pcmo-interface
#10
Kyungjoon Baek, Sangsu Park, Jucheol Park, Young-Min Kim, Hyunsang Hwang, Sang Ho Oh
The interface-type resistive switching devices exhibiting bipolar and multi-level resistive switching have been considered as the key component for neuromorphic device applications. To directly observe the microscopic details of underlying electrochemical redox reactions occuring at a metal/oxide interface, we implemented in situ resistive switching of TiN/Pr0.7Ca0.3MnO3 (PCMO)/Pt junction devices in a transmission electron microscope (TEM). The in situ TEM observations directly show that an intermediate reaction layer (TiOxNy), growing and shrinking in the thickness range of a few nanometers at the TiN/PCMO interface in response to the applied voltage, mainly determines the device resistance by limiting the transport of charge carriers via the Poole-Frenkel conduction mechanism...
November 25, 2016: Nanoscale
https://www.readbyqxmd.com/read/27882264/observation-of-strong-reflection-of-electron-waves-exiting-a-ballistic-channel-at-low-energy
#11
Canute I Vaz, Changze Liu, Jason P Campbell, Jason T Ryan, Richard G Southwick, David Gundlach, Anthony S Oates, Ru Huang, Kin P Cheung
Wave scattering by a potential step is a ubiquitous concept. Thus, it is surprising that theoretical treatments of ballistic transport in nanoscale devices, from quantum point contacts to ballistic transistors, assume no reflection even when the potential step is encountered upon exiting the device. Experiments so far seem to support this even if it is not clear why. Here we report clear evidence of coherent reflection when electron wave exits the channel of a nanoscale transistor and when the electron energy is low...
June 2016: AIP Advances
https://www.readbyqxmd.com/read/27878881/beneficial-effect-of-extracellular-adenosine-5-triphosphate-treatment-on-the-indochinese-leopard-panthera-pardus-delacouri-sperm-quality-after-cryopreservation
#12
P Thuwanut, W Tipkantha, B Siriaroonrat, P Comizzoli, K Chatdarong
The Indochinese leopard (Panthera pardus delacouri) population, included in CITES Appendix I, has been declining for decades. Proper gamete preservation condition is critical for breeding programme management using artificial insemination or in vitro fertilization (IVF). The present study aimed at investigating the impact of post-thawing treatment of leopard semen with extracellular adenosine 5'-triphosphate (ATPe) on sperm quality (including morphological traits and ability to fertilize an oocyte). Semen from six adult male leopards was collected by electroejaculation (one ejaculation per cat)...
November 22, 2016: Reproduction in Domestic Animals, Zuchthygiene
https://www.readbyqxmd.com/read/27876513/are-high-lags-of-accommodation-in-myopic-children-due-to-motor-deficits
#13
Vivek Labhishetty, William R Bobier
Children with a progressing myopia exhibit an abnormal pattern of high accommodative lags coupled with high accommodative convergence (AC/A) and high accommodative adaptation. This is not predicted by the current models of accommodation and vergence. Reduced accommodative plant gain and reduced sensitivity to blur have been suggested as potential causes for this abnormal behavior. These etiologies were tested by altering parameters (sensory, controller and plant gains) in the Simulink model of accommodation...
November 25, 2016: Vision Research
https://www.readbyqxmd.com/read/27875283/does-persistent-inflammatory-catabolic-syndrome-exist-in-critically-ill-neonates
#14
Nicole Ellis, Caitlin Hughes, Vera Mazurak, Chloe Joynt, Bodil Larsen
BACKGROUND: Persistent inflammatory catabolic syndrome (PICS) has not been described in the infant population. This study proposes a definition of PICS in critically ill infants. METHODS: A published adult criterion of PICS was modified using anthropometric and biochemical reference ranges for infants. A prospective chart review of admissions to a tertiary surgical neonatal intensive care unit (NICU) was performed over 65 days. Demographic, anthropometric, biochemical, and other clinical variables such as length of stay and medication use were collected daily throughout admission...
October 10, 2016: JPEN. Journal of Parenteral and Enteral Nutrition
https://www.readbyqxmd.com/read/27872491/solid-liquid-density-and-spin-crossovers-in-mg-fe-o-system-at-deep-mantle-conditions
#15
Dipta B Ghosh, Bijaya B Karki
The low/ultralow-velocity zones in the Earth's mantle can be explained by the presence of partial melting, critically depending on density contrast between the melt and surrounding solid mantle. Here, first-principles molecular dynamics simulations of (Mg, Fe) O ferropericlase in the solid and liquid states show that their densities increasingly approach each other as pressure increases. The isochemical density difference between them diminishes from 0.78 (±0.7) g/cm(3) at zero pressure (3000 K) to 0.16 (±0...
November 22, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27870120/continuous-attractor-network-models-of-grid-cell-firing-based-on-excitatory-inhibitory-interactions
#16
Oliver Shipston-Sharman, Lukas Solanka, Matthew F Nolan
Neurons in the medial entorhinal cortex encode location through spatial firing fields that have a grid-like organisation. The challenge of identifying mechanisms for grid firing has been addressed through experimental and theoretical investigations of medial entorhinal circuits. Here, we discuss evidence for continuous attractor network models that account for grid firing by synaptic interactions between excitatory and inhibitory cells. These models assume that grid-like firing patterns are the result of computation of location from velocity inputs, with additional spatial input required to oppose drift in the attractor state...
November 15, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27865773/particulate-suspension-effect-on-peristaltically-induced-unsteady-pulsatile-flow-in-a-narrow-artery-blood-flow-model
#17
Sara I Abdelsalam, Kambiz Vafai
This work is concerned with theoretically investigating the pulsatile flow of a fluid with suspended particles in a flow driven by peristaltic waves that deform the wall of a small blood artery in the shape of traveling sinusoidal waves with constant velocity. The problem formulation in the wave frame of reference is presented and the governing equations are developed up to the second-order in terms of the asymptotic expansion of Womersley number which characterizes the unsteady effect in the wave frame. We suppose that the flow rate imposed, in this frame, is a function versus time...
November 16, 2016: Mathematical Biosciences
https://www.readbyqxmd.com/read/27863131/conditions-of-microvessel-occlusion-for-blood-coagulation-in-flow
#18
A Bouchnita, T Galochkina, P Kurbatova, P Nony, V Volpert
Vessel occlusion is a perturbation of blood flow inside a blood vessel because of the fibrin clot formation. As a result, blood circulation in the vessel can be slowed down or even stopped. This can provoke the risk of cardiovascular events. In order to explore this phenomenon, we used a previously developed mathematical model of blood clotting to describe the concentrations of blood factors with a reaction-diffusion system of equations. The Navier-Stokes equations were used to model blood flow and we treated the clot as a porous medium...
November 10, 2016: International Journal for Numerical Methods in Biomedical Engineering
https://www.readbyqxmd.com/read/27861125/4-aminopyridine-promotes-functional-recovery-and-remyelination-in-acute-peripheral-nerve-injury
#19
Kuang-Ching Tseng, Haiyan Li, Andrew Clark, Leigh Sundem, Michael Zuscik, Mark Noble, John Elfar
Traumatic peripheral nerve damage is a major medical problem without effective treatment options. In repurposing studies on 4-aminopyridine (4-AP), a potassium channel blocker that provides symptomatic relief in some chronic neurological afflictions, we discovered this agent offers significant promise as a small molecule regenerative agent for acute traumatic nerve injury. We found, in a mouse model of sciatic crush injury, that sustained early 4-AP administration increased the speed and extent of behavioral recovery too rapidly to be explained by axonal regeneration...
December 1, 2016: EMBO Molecular Medicine
https://www.readbyqxmd.com/read/27856098/gastric-perforation-and-critical-illness-polyneuropathy-after-steroid-treatment-in-a-patient-with-encephalitis-encephalopathy-with-transient-splenial-lesion
#20
Mitsuru Ikeno, Shinpei Abe, Hirokazu Kurahashi, Michihiko Takasu, Toshiaki Shimizu, Akihisa Okumura
The outcome of mild encephalitis/encephalopathy with reversible splenial lesion (MERS) is favorable whether or not specific treatment is performed. We report a patient with MERS treated with methylprednisolone, complicated by gastric perforation followed by critical illness polyneuropathy. The patient was a 14-year-old male with mildly impaired consciousness and hyponatremia who was treated with methylprednisolone pulse therapy. High fever appeared after methylprednisolone pulse therapy and free air was recognized on an abdomen roentgenogram...
November 14, 2016: Brain & Development
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