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https://www.readbyqxmd.com/read/29028619/development-of-a-high-performance-liquid-chromatography-method-for-the-determination-of-florfenicol-in-animal-feedstuffs
#1
JinJing Yang, GuiZhi Sun, MingRong Qian, LingLi Huang, XianBing Ke, Bo Yang
An effective thin layer chromatography (TLC) purification procedure coupled to high-performance liquid chromatography (HPLC) method was developed for the determination of florfenicol (FF) in pig, chicken and fish feedstuffs. The feedstuff samples were extracted with ethyl acetate, defatted with n-hexane saturated with acetonitrile, and further purified by TLC. The chromatographic separation was performed on a Waters Symmetry C18 column using an isocratic procedure with acetonitrile-water (35:65, v/v) at 0.6mL/min...
September 29, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29028041/comparing-mode-crosstalk-and-mode-dependent-loss-of-laterally-displaced-orbital-angular-momentum-and-hermite-gaussian-modes-for-free-space-optical-communication
#2
Bienvenu Ndagano, Nokwazi Mphuthi, Giovanni Milione, Andrew Forbes
There is interest in using orbital angular momentum (OAM) modes to increase the data speed of free-space optical communication. A prevalent challenge is the mitigation of mode-crosstalk and mode-dependent loss that is caused by the modes' lateral displacement at the data receiver. Here, the mode-crosstalk and mode-dependent loss of laterally displaced OAM modes (LG0,+1, LG0,-1) are experimentally compared to that of a Hermite-Gaussian (HG) mode subset (HG0,1, HG1,0). It is shown, for an aperture larger than the modes' waist sizes, some of the HG modes can experience less mode-crosstalk and mode-dependent loss when laterally displaced along a symmetry axis...
October 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/29028016/measuring-the-electromagnetic-chirality-of-2d-arrays-under-normal-illumination
#3
X Garcia-Santiago, S Burger, C Rockstuhl, I Fernandez-Corbaton
We present an electromagnetic chirality measure for 2D arrays of subwavelength periodicities under normal illumination. The calculation of the measure uses only the complex reflection and transmission coefficients from the array. The measure allows the ordering of arrays according to their electromagnetic chirality, which further allows a quantitative comparison of different design strategies. The measure is upper bounded, and the extreme properties of objects with high values of electromagnetic chirality make them useful in both near- and far-field applications...
October 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/29028014/classes-of-non-parity-time-symmetric-optical-potentials-with-exceptional-point-free-phase-transitions
#4
Jianke Yang
Paraxial linear propagation of light in an optical waveguide with material gain and loss is governed by a Schrödinger equation with a complex potential. In this Letter, new classes of non-parity-time (PT)-symmetric complex potentials featuring conjugate-pair eigenvalue symmetry are constructed by operator symmetry methods. Due to this eigenvalue symmetry, it is shown that the spectrum of these complex potentials is often all-real. Under parameter tuning in these potentials, a phase transition can also occur, where pairs of complex eigenvalues appear in the spectrum...
October 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/29027549/lifetime-nanomanometry-high-pressure-luminescence-of-up-converting-lanthanide-nanocrystals-srf2-yb-3-er-3
#5
Marcin Runowski, Jędrzej Marciniak, Tomasz Grzyb, Dominika Przybylska, Andrii Shyichuk, Bolesław Barszcz, Andrzej Katrusiak, Stefan Lis
Anti-Stokes luminescence of up-converting nanocrystals SrF2:Yb(3+),Er(3+) can be used as a high pressure optical sensor alternative to the ruby fluorescence-scale. In nanocrystalline SrF2:Yb(3+),Er(3+), high pressure reversibly shortens the emission lifetimes nearly linearly up to 5.29 GPa at least. Its advantage is the use of NIR (≈980 nm) radiation, highly penetrable for many materials. The shortening of up-conversion lifetimes has been attributed mainly to the changes in energy transfer rates, caused by decreased interatomic distances and increased overlap integrals between 4f electrons and the valence shells of ligand ions...
October 13, 2017: Nanoscale
https://www.readbyqxmd.com/read/29026828/objective-outcomes-of-minimally-invasive-temporalis-tendon-transfer-for-prolonged-complete-facial-paralysis
#6
Michal Brichacek, Babar Sultan, Kofi D Boahene, Lisa Ishii, Patrick J Byrne
OBJECTIVES: We describe an approach to reanimation of complete, prolonged facial paralysis using minimally invasive temporalis tendon transfer (MIT3) by the melolabial or transoral approach. Objective outcome measures are evaluated based on symmetry, and grading of preoperative/post-operative results and the scar at the melolabial fold. STUDY DESIGN: Retrospective cohort study. METHODS: Twenty-five patients undergoing the MIT3 technique were studied...
August 2017: Plastic Surgery
https://www.readbyqxmd.com/read/29026827/evaluation-of-secondary-and-late-secondary-alveolar-bone-grafting-on-66-unilateral-cleft-lip-and-palate-patients
#7
Ravi Mahajan, Harish Ghildiyal, Ankit Khasgiwala, Gogulnathan Muthukrishnan, Sukhdeep Kahlon
OBJECTIVE: The aim of this retrospective study was to evaluate the outcomes of secondary alveolar bone grafting and late secondary alveolar bone grafting in 66 unilateral cleft lip and palate patients. MATERIALS AND METHODS: The total patients were 66 unilateral cleft lip and palate patients, out of which 19 patients underwent secondary alveolar bone grafting and 47 patients underwent late secondary alveolar bone grafting. Autogenous anterior iliac crest cancellous bone graft was harvested and used for grafting the alveolar clefts...
August 2017: Plastic Surgery
https://www.readbyqxmd.com/read/29023934/spontaneous-emergence-of-legibility-in-writing-systems-the-case-of-orientation-anisotropy
#8
Olivier Morin
Cultural forms are constrained by cognitive biases, and writing is thought to have evolved to fit basic visual preferences, but little is known about the history and mechanisms of that evolution. Cognitive constraints have been documented for the topology of script features, but not for their orientation. Orientation anisotropy in human vision, as revealed by the oblique effect, suggests that cardinal (vertical and horizontal) orientations, being easier to process, should be overrepresented in letters. As this study of 116 scripts shows, the orientation of strokes inside written characters massively favors cardinal directions, and it is organized in such a way as to make letter recognition easier: Cardinal and oblique strokes tend not to mix, and mirror symmetry is anisotropic, favoring vertical over horizontal symmetry...
October 10, 2017: Cognitive Science
https://www.readbyqxmd.com/read/29023694/adaptive-self-organization-in-the-embryo-its-importance-to-adult-anatomy-and-to-tissue-engineering
#9
REVIEW
Jamie A Davies
The anatomy of healthy humans shows much minor variation, and twin-studies reveal at least some of this variation cannot be explained genetically. A plausible explanation is that fine-scale anatomy is not specified directly in a genetic programme, but emerges from self-organizing behaviours of cells that, for example, place a new capillary where it happens to be needed to prevent local hypoxia. Self-organizing behaviour can be identified by manipulating growing tissues (e.g. putting them under a spatial constraint) and observing an adaptive change that conserves the character of the normal tissue while altering its precise anatomy...
October 10, 2017: Journal of Anatomy
https://www.readbyqxmd.com/read/29023579/role-of-the-n-terminus-for-the-stability-of-an-amyloid-%C3%AE-fibril-with-three-fold-symmetry
#10
Christian A Söldner, Heinrich Sticht, Anselm H C Horn
A key player in Alzheimer's disease is the peptide amyloid-beta (Aβ), whose aggregation into small soluble oligomers, protofilaments, and fibrils finally leads to plaque deposits in human brains. The aggregation behavior of Aβ is strongly modulated by the nature and composition of the peptide's environment and by its primary sequence properties. The N-terminal residues of Aβ play an important role, because they are known to change the peptide's aggregation propensity. Since these residues are for the first time completely resolved at the molecular level in a three-fold symmetric fibril structure derived from a patient, we chose that system as template for a systematic investigation of the influence of the N-terminus upon structural stability...
2017: PloS One
https://www.readbyqxmd.com/read/29023456/gait-parameters-are-differently-affected-by-concurrent-smartphone-based-activities-with-scaled-levels-of-cognitive-effort
#11
Carlotta Caramia, Ivan Bernabucci, Carmen D'Anna, Cristiano De Marchis, Maurizio Schmid
The widespread and pervasive use of smartphones for sending messages, calling, and entertainment purposes, mainly among young adults, is often accompanied by the concurrent execution of other tasks. Recent studies have analyzed how texting, reading or calling while walking-in some specific conditions-might significantly influence gait parameters. The aim of this study is to examine the effect of different smartphone activities on walking, evaluating the variations of several gait parameters. 10 young healthy students (all smartphone proficient users) were instructed to text chat (with two different levels of cognitive load), call, surf on a social network or play with a math game while walking in a real-life outdoor setting...
2017: PloS One
https://www.readbyqxmd.com/read/29023307/interrater-agreement-of-eeg-interpretation-after-pediatric-cardiac-arrest-using-standardized-critical-care-eeg-terminology
#12
Nicholas S Abend, Shavonne L Massey, Mark Fitzgerald, France Fung, Natalie J Atkin, Rui Xiao, Alexis A Topjian
PURPOSE: We evaluated interrater agreement of EEG interpretation in a cohort of critically ill children resuscitated after cardiac arrest using standardized EEG terminology. METHODS: Four pediatric electroencephalographers scored 10-minute EEG segments from 72 consecutive children obtained 24 hours after return of circulation using the American Clinical Neurophysiology Society's (ACNS) Standardized Critical Care EEG terminology. The percent of perfect agreement and the kappa coefficient were calculated for each of the standardized EEG variables and a predetermined composite EEG background category...
October 10, 2017: Journal of Clinical Neurophysiology: Official Publication of the American Electroencephalographic Society
https://www.readbyqxmd.com/read/29022971/elastic-moduli-of-biological-fibers-in-a-coarse-grained-model-crystalline-cellulose-and-%C3%AE-amyloids
#13
Adolfo B Poma, Mateusz Chwastyk, Marek Cieplak
We study the mechanical response of cellulose and β-amyloid microfibrils to three types of deformation: tensile, indentational, and shear. The cellulose microfibrils correspond to the allomorphs Iα or Iβ whereas the β-amyloid microfibrils correspond to the polymorphs of either two- or three-fold symmetry. This response can be characterized by three elastic moduli, namely, YL, YT, and S. We use a structure-based coarse-grained model to analyze the deformations in a unified manner. We find that each of the moduli is almost the same for the two allomorphs of cellulose but YL is about 20 times larger than YT (140 GPa vs...
October 12, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29022968/the-structure-of-coronene-cluster-ions-inferred-from-h2-uptake-in-the-gas-phase
#14
Marcelo Goulart, Martin Kuhn, Bilal Rasul, Johannes Postler, Michael Gatchell, Henning Zettergren, Paul Scheier, Olof Echt
Mass spectra of helium nanodroplets doped with H2 and coronene feature anomalies in the ion abundance that reveal anomalies in the energetics of adsorption sites. The coronene monomer ion strongly adsorbs up to n = 38 H2 molecules indicating a commensurate solvation shell that preserves the D6h symmetry of the substrate. No such feature is seen in the abundance of the coronene dimer through tetramer complexed with H2; this observation rules out a vertical columnar structure. Instead we see evidence for a columnar structure in which adjacent coronenes are displaced in parallel, forming terraces that offer additional strong adsorption sites...
October 12, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29022738/an-exploration-of-the-symmetry-between-crime-causing-and-crime-reducing-factors-implications-for-delivery-of-offender-services
#15
Daryl G Kroner, Devon L L Polaschek, Ralph C Serin, Jennifer L Skeem
Both the Risk-Needs-Responsivity (RNR) and Structured Professional Judgment (SPJ) risk assessment approaches assume that a strong relationship exists between crime-causing and crime reducing factors. Using a probation sample, the present article examines whether crime-causing and crime-reducing factors correspond. Probationers completed questionnaires where they were asked what factors were crime-causing and what factors were crime-reducing. Overall, the relationship between the crime-causing and crime-reducing factors was very weak-even after ruling out potential measurement and methodological artifacts (i...
October 12, 2017: Psychological Services
https://www.readbyqxmd.com/read/29022604/assembly-of-high-symmetry-silver-i-alkyl-1-3-diynyl-cluster-complexes-via-core-transformation
#16
Sam C K Hau, Thomas C W Mak
New tetranuclear supramolecular precursors [(R-C[triple bond, length as m-dash]C-C[triple bond, length as m-dash]C)Ag(PPh3)]4 (R = iPr and chx) are employed to construct three polynuclear silver(i) alkyl-1,3-diynyl cluster complexes (1-3) that bear the same novel trigonal bipyramidal Ag5 core consolidated by silver-ethynide and argentophilic interactions. The present results strongly suggest that the assembly of high-symmetry medium-nuclearity clusters 1-3 is initiated by the accretion of additional Ag(i) ions by the Ag4 template of the precursors through argentophilic (<3...
October 12, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/29021992/classifying-symmetrical-differences-and-temporal-change-for-the-detection-of-malignant-masses-in-mammography-using-deep-neural-networks
#17
Thijs Kooi, Nico Karssemeijer
We investigate the addition of symmetry and temporal context information to a deep convolutional neural network (CNN) with the purpose of detecting malignant soft tissue lesions in mammography. We employ a simple linear mapping that takes the location of a mass candidate and maps it to either the contralateral or prior mammogram, and regions of interest (ROIs) are extracted around each location. Two different architectures are subsequently explored: (1) a fusion model employing two datastreams where both ROIs are fed to the network during training and testing and (2) a stagewise approach where a single ROI CNN is trained on the primary image and subsequently used as a feature extractor for both primary and contralateral or prior ROIs...
October 2017: Journal of Medical Imaging
https://www.readbyqxmd.com/read/29021626/vector-form-of-symmetry-degree
#18
G H Dong, Z W Zhang, C P Sun, Z R Gong
Symmetry degree is utilized to characterize the asymmetry of a physical system with respect to a symmetry group. The scalar form of symmetry degree (SSD) based on Frobenius-norm has been introduced recently to present a quantitative description of symmetry. Here we present the vector form of the symmetry degree (VSD) which possesses more advantages than the SSD. Mathematically, the dimension of VSD is defined as the conjugacy class number of the symmetry group, the square length of the VSD gives rise to the SSD and the direction of VSD is determined by the orders of the conjugacy classes...
October 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29021618/superconductivity-in-empty-bands-and-multiple-order-parameter-chirality
#19
Robert Joynt, Wen-Chin Wu
Recent experiments have shown rotation of the plane of polarization of light reflected from the surface of some superconductors. The photon energy exceeds the electronic bandwidth, so that completely filled or completely empty bands must play a role. We show that in strong-coupling theory a Coulomb interaction can produce an order parameter in the unoccupied band that explains the observations. Thus the phenomenology puts tight constraints on the form of the order parameter in different bands. We propose that the experiments have detected, for the first time, the existence of a superconducting order parameter in a band far from the Fermi energy...
October 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29021491/effects-of-sterol-like-additives-on-phase-transition-behavior-of-ion-pair-amphiphile-bilayers
#20
Wei-Han Chang, Yun-Ting Chuang, Cheng-Yeh Yu, Chien-Hsiang Chang, Yu-Min Yang
The incorporation of additive in lipid bilayers is one of the ordinary approaches for modulating their properties. Additive effect on phase transition of ion-pair amphiphile (IPA) bilayers, however, is not known. In this work, four double-chained IPAs with different hydrocarbon chain lengths and symmetry were designed and synthesized from single-chained cationic and anionic surfactants by the precipitation method. By using differential scanning calorimetry (DSC), the thermotropic transition behavior from gel phase (Lβ) through rippled phase (Pβ') if any to liquid-crystalline phase (Lα) was studied for bilayers of these lipid-like IPAs in excess water...
October 11, 2017: Journal of Oleo Science
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