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https://www.readbyqxmd.com/read/28814017/assessment-of-lower-arm-movements-using-one-inertial-sensor
#1
Fokke B van Meulen, Bert-Jan F van Beijnum, Jaap H Buurke, Peter H Veltink
Reduction of the number of sensors needed to evaluate arm movements, makes a system for the assessment of human body movements more suitable for clinical practice and daily life assessments. In this study, we propose an algorithm to reconstruct lower arm orientation, velocity and position, based on a sensing system which consists of only one inertial measurement unit (IMU) to the forearm. Lower arm movements were reconstructed using a single IMU and assuming that within a measurement there are moments without arm movements...
July 2017: IEEE ... International Conference on Rehabilitation Robotics: [proceedings]
https://www.readbyqxmd.com/read/28813938/online-sparse-gaussian-process-based-human-motion-intent-learning-for-an-electrically-actuated-lower-extremity-exoskeleton
#2
Yi Long, Zhi-Jiang Du, Chao-Feng Chen, Wei Dong, Wei-Dong Wang
The most important step for lower extremity exoskeleton is to infer human motion intent (HMI), which contributes to achieve human exoskeleton collaboration. Since the user is in the control loop, the relationship between human robot interaction (HRI) information and HMI is nonlinear and complicated, which is difficult to be modeled by using mathematical approaches. The nonlinear approximation can be learned by using machine learning approaches. Gaussian Process (GP) regression is suitable for high-dimensional and small-sample nonlinear regression problems...
July 2017: IEEE ... International Conference on Rehabilitation Robotics: [proceedings]
https://www.readbyqxmd.com/read/28813902/hybrid-position-and-orientation-tracking-for-a-passive-rehabilitation-table-top-robot
#3
K K Wojewoda, P R Culmer, J F Gallagher, A E Jackson, M C Levesley
This paper presents a real time hybrid 2D position and orientation tracking system developed for an upper limb rehabilitation robot. Designed to work on a table-top, the robot is to enable home-based upper-limb rehabilitative exercise for stroke patients. Estimates of the robot's position are computed by fusing data from two tracking systems, each utilizing a different sensor type: laser optical sensors and a webcam. Two laser optical sensors are mounted on the underside of the robot and track the relative motion of the robot with respect to the surface on which it is placed...
July 2017: IEEE ... International Conference on Rehabilitation Robotics: [proceedings]
https://www.readbyqxmd.com/read/28813607/nonlinear-raman-effects-enhanced-by-surface-plasmon-excitation-in-planar-refractory-nano-antennas
#4
Sergey S Kharintsev, Anton Kharitonov, Semion Saikin, Alexander M Alekseev, Sergei G Kazarian
We consider a nonlinear mechanism of localized light inelastic scattering within nano-patterned plasmonic and Raman-active titanium nitride (TiN) thin films exposed to continuous-wave (cw) modest-power laser light. Owing to the strong third-order nonlinear interaction between optically excited broadband surface plasmons and localized Stokes and anti-Stokes waves, both stimulated and inverse Raman effects can be observed. We provide experimental evidences for coherent amplification of the localized Raman signals using a planar square shaped refractory antenna...
August 16, 2017: Nano Letters
https://www.readbyqxmd.com/read/28813603/modeling-optical-spectra-of-large-organic-systems-using-real-time-propagation-of-semiempirical-effective-hamiltonians
#5
Soumen Ghosh, Amity Andersen, Laura Gagliardi, Christopher J Cramer, Niranjan Govind
We present an implementation of a time-dependent semiempirical method (INDO/S) in NWChem using real-time (RT) propagation to address, in principle, the entire spectrum of valence electronic excitations. Adopting this model, we study the UV-visible spectra of medium-sized systems like P3B2, f-coronene, and in addition much larger systems like ubiquitin in the gas phase and the betanin chromophore in the presence of two explicit solvents (water and methanol). RT-INDO/S provides qualitatively and indeed often quantitatively accurate results when compared with RT- TDDFT or experimental spectra...
August 16, 2017: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/28813577/spatial-correspondence-between-intraretinal-fluid-subretinal-fluid-and-pigment-epithelial-detachment-in-neovascular-age-related-macular-degeneration
#6
Sophie Klimscha, Sebastian M Waldstein, Thomas Schlegl, Hrvoje Bogunovic, Amir Sadeghipour, Ana-Maria Philip, Dominika Podkowinski, Eleonore Pablik, Li Zhang, Michael D Abramoff, Milan Sonka, Bianca S Gerendas, Ursula Schmidt-Erfurth
Purpose: To identify the spatial distribution of exudative features of choroidal neovascularization in neovascular age-related macular degeneration (nAMD) based on the localization of intraretinal cystoid fluid (IRC), subretinal fluid (SRF), and pigment-epithelial detachment (PED). Methods: This retrospective cross-sectional study included spectral-domain optical coherence tomography volume scans (6 × 6 mm) of 1341 patients with treatment-naïve nAMD. IRC, SRF, and PED were detected on a per-voxel basis using fully automated segmentation algorithms...
August 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28813574/dynamic-imaging-of-the-eye-optic-nerve-and-extraocular-muscles-with-golden-angle-radial-mri
#7
Saikat Sengupta, David S Smith, Alex K Smith, E Brian Welch, Seth A Smith
Purpose: The eye and its accessory structures, the optic nerve and the extraocular muscles, form a complex dynamic system. In vivo magnetic resonance imaging (MRI) of this system in motion can have substantial benefits in understanding oculomotor functioning in health and disease, but has been restricted to date to imaging of static gazes only. The purpose of this work was to develop a technique to image the eye and its accessory visual structures in motion. Methods: Dynamic imaging of the eye was developed on a 3-Tesla MRI scanner, based on a golden angle radial sequence that allows freely selectable frame-rate and temporal-span image reconstructions from the same acquired data set...
August 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28813485/magnetic-lenz-lenses-improve-the-limit-of-detection-in-nuclear-magnetic-resonance
#8
Nils Spengler, Peter T While, Markus V Meissner, Ulrike Wallrabe, Jan G Korvink
A high NMR detection sensitivity is indispensable when dealing with mass and volume-limited samples, or whenever a high spatial resolution is required. The use of miniaturised RF coils is a proven way to increase sensitivity, but situations may arise where space restrictions could prevent the use of a small resonant coil, e.g., in the interior of the smallest practicable micro-coils. We present the use of magnetic lenses, denoted as Lenz lenses due to their working principle, to focus the magnetic flux of an RF coil into a smaller volume and thereby locally enhance the sensitivity of the NMR experiment-at the expense of the total sensitive volume...
2017: PloS One
https://www.readbyqxmd.com/read/28813435/chronic-imaging-through-transparent-skull-in-mice
#9
Anna Steinzeig, Dmitry Molotkov, Eero Castrén
Growing interest in long-term visualization of cortical structure and function requires methods that allow observation of an intact cortex in longitudinal imaging studies. Here we describe a detailed protocol for the "transparent skull" (TS) preparation based on skull clearing with cyanoacrylate, which is applicable for long-term imaging through the intact skull in mice. We characterized the properties of the TS in imaging of intrinsic optical signals and compared them with the more conventional cranial window preparation...
2017: PloS One
https://www.readbyqxmd.com/read/28813154/on-the-roles-of-free-electrons-and-h2o2-in-the-optical-breakdown-induced-photochemical-reduction-of-aqueous-aucl4
#10
Victoria Kathryn Meader, Mallory G John, Collin J Rodrigues, Katharine Moore Tibbetts
Free electrons and H2O2 formed in an optical breakdown plasma are found to di- rectly control the kinetics of [AuCl4]- reduction to form Au nanoparticles (AuNPs) during femtosecond laser-assisted synthesis of AuNPs. The formation rates of both free electrons and H2O2 strongly depend on the energy and duration of the 800 nm laser pulses over the ranges of 10 - 2400 μJ and 30 - 1500 fs. By monitoring the conversion of [AuCl4]- to AuNPs using in situ UV-vis spectroscopy during laser irradiation, the first- and second-order rate constants in the autocatalytic rate law, k1 and k2, were extracted and compared to the computed free electron densities and experimentally measured H2O2 formation rates...
August 16, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28813152/coherent-exciton-delocalization-in-a-two-state-dna-templated-dye-aggregate-system
#11
Brittany L Cannon, Donald L Kellis, Lance Kenneth Patten, Paul H Davis, Jeunghoon Lee, Elton Graugnard, Bernard Yurke, William B Knowlton
Coherent exciton delocalization in dye aggregate systems gives rise to a variety of intriguing optical phenomena, including J- and H-aggregate behavior and Davydov splitting. Systems that exhibit coherent exciton delocalization at room temperature are of interest for the development of artificial light-harvesting devices, colorimetric detection schemes, and quantum computers. Here, we report on a simple dye system templated by DNA that exhibits tunable optical properties. At low salt and DNA concentrations, a DNA duplex with two internally functionalized Cy5 dyes (i...
August 16, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28813142/atomic-force-microscopy-infrared-spectroscopy-of-individual-atmospheric-aerosol-particles-sub-diffraction-limit-vibrational-spectroscopy-and-morphological-analysis
#12
Amy Lynne Bondy, Rachel M Kirpes, Rachel Leah Merzel, Kerri A Pratt, Mark M Banaszak Holl, Andrew P Ault
Chemical analysis of atmospheric aerosols is an analytical challenge, as aerosol particles are complex chemical mixtures that can contain hundreds to thousands of species in attoliter volumes at the most abundant sizes in the atmosphere (~100 nm). These particles have global impacts on climate and health, but there are few methods available that combine imaging and the detailed molecular information from vibrational spectroscopy for individual particles <500 nm. Herein, we show the first application of atomic force microscopy with infrared spectroscopy (AFM-IR) to detect trace organic and inorganic species and probe intraparticle chemical variation in individual particles down to 150 nm...
August 16, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28813066/multivalent-mesoporous-silica-nanoparticles-photo-delivering-nitric-oxide-with-carbon-dots-as-fluorescence-reporters
#13
Damien Afonso, Sabrina Valetti, Aurore Fraix, Claudia Bascetta, Salvatore Petralia, Sabrina Conoci, Adam Feiler, Salvatore Sortino
Amino-terminated mesoporous silica nanoparticles embedding carbon dots (MSCD) formed by calcination were functionalized with a nitric oxide (NO) photodonor (1) to give a robust MSCD-1 conjugate. The intense fluorescence of MSCDs was strongly quenched in MSCD-1 by effective energy transfer. Visible light excitation of MSCD-1 liberates NO, suppresses the energy transfer mechanism and leads to concomitant fluorescence restoration of the MSCD scaffold, which acts as an optical reporter for the released NO. The MSCD-1 hybrid is also able to encapsulate the highly hydrophobic photosensitizer temoporfin, preserving the fluorescence reporting function...
August 16, 2017: Nanoscale
https://www.readbyqxmd.com/read/28813053/copper-ii-benzimidazole-complexes-as-efficient-fluorescent-probes-for-l-cysteine-in-water
#14
Duraiyarasu Maheshwaran, Selvarasu Priyanga, Ramasamy Mayilmurugan
Copper(ii) complexes [Cu(L1)(H2O)2](SO3CF3)21 and [Cu(L2)(H2O)2](SO3CF3)22 based on 2,6-bis(benzimidazolyl)pyridine were synthesized and are reported herein as highly selective "turn-on" optical probes for l-cysteine. The Cu(ii)/Cu(i) redox potential of probe 1 (0.14 V vs. NHE) was lower than that of 2 (0.233 V vs. NHE) in water. The molecular structure of 2 adopted a square pyramidal geometry (τ = 0.2545), with the Cu-Npy bond (1.958 Å) of its middle pyridine unit being shorter than the other two Cu-Nbenzim bonds (Cu-N, 1...
August 16, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28813044/short-bent-core-molecules-x-ray-polarization-dielectricity-texture-and-electro-optics-investigations
#15
S Torgova, S P Sreenilayam, Yu P Panarin, O Francescangeli, F Vita, J K Vij, E Pozhidaev, M Minchenko, C Ferrero, A Strigazzi
Bent-core liquid crystals based on 1,2,4-oxadiazole as a central unit have been the first mesogens to exhibit a ferroelectric response in the nematic phase. This behavior has been widely recognized as due to the presence of smectic-like polar cybotactic clusters permeating the nematic phase. Unfortunately, these compounds exhibited rather high melting points, about 120 °C, due to the presence of four benzene rings in the molecules. Here we describe the synthesis and physical characterization of a new series of BC mesogens, featuring the same bent core as the previous compounds but shorter outer substituents...
August 16, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28813006/samarium-monosulfide-sms-reviewing-properties-and-applications
#16
REVIEW
Andreas Sousanis, Philippe F Smet, Dirk Poelman
In this review, we give an overview of the properties and applications of samarium monosulfide, SmS, which has gained considerable interest as a switchable material. It shows a pressure-induced phase transition from the semiconducting to the metallic state by polishing, and it switches back to the semiconducting state by heating. The material also shows a magnetic transition, from the paramagnetic state to an antiferromagnetically ordered state. The switching behavior between the semiconducting and metallic states could be exploited in several applications, such as high density optical storage and memory materials, thermovoltaic devices, infrared sensors and more...
August 16, 2017: Materials
https://www.readbyqxmd.com/read/28812956/toxicity-identification-and-evaluation-for-the-effluent-from-a-nonmetallic-mineral-mining-facility-in-korea-using-d-magna
#17
Sungjong Lee, Hongjoo Ha, JinKyung Hong, Guyoung Kang, Chunsang Hong
Industrial wastewater has attracted increasing attention in recent years because of its impact on ecosystems and human health. Whole-effluent tests are generally used to monitor toxicities of unknown chemicals and conventional pollutants from industrial effluent discharges. This study described identification evaluation (TIE) procedures to determine the acute toxicity of a nonmetallic mineral mining facility effluent that was toxic to Daphnia magna. In the characterization step (TIE phase I), toxic effects of heavy metals, organic compounds, oxidants, volatile organic compounds, suspended solids, and ammonia were screened...
January 1, 2017: Toxicology and Industrial Health
https://www.readbyqxmd.com/read/28812938/unilateral-optic-perineuritis-due-to-nonspecific-orbital-inflammation-a-case-report
#18
Pinar Nalcacioglu, Golge Acaroglu
Nonspecific orbital inflammation is an idiopathic chronic tumor-like inflammation process that usually affects the orbital tissues of both eyes. Isolated optic nerve involvement by an idiopathic inflammatory process is a rare finding. Here, we report a patient with unilateral sudden onset severe orbital pain and headache with visual loss to no light perception that could only be attributed to perineuritis. Radiological findings enabled making the correct diagnosis. Various relevant diagnoses are also discussed...
August 16, 2017: Orbit
https://www.readbyqxmd.com/read/28812914/retrospective-chart-review-of-the-use-of-imaging-and-biopsy-in-the-diagnosis-of-optic-nerve-sheath-meningiomas-and-intra-conal-orbital-lymphomas-at-a-single-institution
#19
Anna Parlin, Alina Dumitrescu, William T Nunery, Peter J Timoney, Jason A Sokol
Optic nerve sheath meningiomas (ONSM) and intra-conal orbital lymphomas are common entities on the differential of a retrobulbar optic nerve involving space-occupying lesion. In this study, we compare the pre-surgical diagnosis, based on clinical presentation and neuroimaging, to the surgical pathology results of intra-conal orbital lymphomas and ONSM. This is an IRB approved retrospective chart review of orbital lymphomas and optic nerve sheath meningiomas biopsied by a single surgeon over a 4-year period at a single institution...
August 16, 2017: Orbit
https://www.readbyqxmd.com/read/28812909/chronic-orbital-inflammatory-disease-and-optic-neuropathy-associated-with-long-term-intranasal-cocaine-abuse-2-cases-and-literature-review
#20
Martin J Siemerink, Nicole J M Freling, Peerooz Saeed
Orbital inflammatory disease and secondary optic neuropathy is a rare but devastating complication of long-term intranasal cocaine abuse. We describe 2 patients with a history of intranasal cocaine consumption who presented with subacute onset of unilateral vision loss from optic neuropathy and limitation of abduction in the affected eye. Magnetic resonance imaging findings included an orbital mass in combination with absent nasal septum and partial destruction of the paranasal sinuses. Biopsies and histopathologic examination of the nasal cavity and the orbital mass revealed chronic inflammation...
August 16, 2017: Orbit
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