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https://www.readbyqxmd.com/read/28214736/breaking-the-population-barrier-by-single-cell-analysis-one-host-against-one-pathogen
#1
REVIEW
Erez Mills, Roi Avraham
Most of our understanding of the host-bacterium interaction has come from studies of bulk populations. In reality, highly adaptable and dynamic host cells and bacteria engage in complex, diverse interactions. This complexity necessarily limits the depth of understanding that can be gained with bulk population measurements. Here, we will review the merit of single cell analysis to characterize this diversity that can trigger heterogeneous outcomes. We will discuss heterogeneity of bacterial and host populations, differences in host microenvironments, technological advances that facilitate the analysis of rare subpopulations, and the potential relevance of these subpopulations to infection outcomes...
February 16, 2017: Current Opinion in Microbiology
https://www.readbyqxmd.com/read/28213112/laminar-imaging-of-positive-and-negative-bold-in-human-visual-cortex-at-7t
#2
Alessio Fracasso, Peter R Luijten, Serge O Dumoulin, Natalia Petridou
Deciphering the direction of information flow is critical to understand the brain. Data from non-human primate histology shows that connections between lower to higher areas (e.g. retina→V1), and between higher to lower areas (e.g. V1←V2) can be dissociated based upon the distribution of afferent synapses at the laminar level. Ultra-high field scanners opened up the possibility to image brain structure and function at an unprecedented level of detail. Taking advantage of the increased spatial resolution available, it could theoretically be possible to disentangle activity from different cortical depths from human cerebral cortex, separately studying different compartments across depth...
February 14, 2017: NeuroImage
https://www.readbyqxmd.com/read/28212083/aliasing-detection-and-reduction-scheme-on-angularly-undersampled-light-fields
#3
Zhaolin Xiao, Qing Wang, Guoqing Zhou, Jingyi Yu
When using plenoptic camera for digital refocusing, angular undersampling can cause severe (angular) aliasing artifacts. Previous approaches have focused on avoiding aliasing by pre-processing the acquired light field via prefiltering, demosaicing, reparameterization, etc. In this paper, we present a different solution that first detects and then removes angular aliasing at the light field refocusing stage. Different from previous frequency domain aliasing analysis, we carry out a spatial domain analysis to reveal whether the angular aliasing would occur and uncover where in the image it would occur...
February 13, 2017: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
https://www.readbyqxmd.com/read/28211796/fluence-correction-factor-for-graphite-calorimetry-in-a-clinical-high-energy-carbon-ion-beam
#4
Ana Lourenco, Russell Thomas, Michael Homer, Hugo Bouchard, Severine Rossomme, James Renaud, Tatsuaki Kanai, Gary Royle, Hugo Palmans
The aim of this work is to develop and adapt a formalism to determine absorbed dose to water from graphite calorimetry measurements in carbon-ion beams. Fluence correction factors, <i>k</i><sub>fl</sub>, needed when using a graphite calorimeter to derive dose to water, were determined in a clinical high-energy carbon-ion beam. Measurements were performed in a 290 MeV/n carbon-ion beam with a field size of 11 x 11 cm<sup>2</sup>, without modulation. In order to sample the beam, a plane-parallel Roos ionization chamber was chosen for its small collecting volume in comparison with the field size...
February 17, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28211471/phosphorene-quantum-dot-saturable-absorbers-for-ultrafast-fiber-lasers
#5
J Du, M Zhang, Z Guo, J Chen, X Zhu, G Hu, P Peng, Z Zheng, H Zhang
We fabricate ultrasmall phosphorene quantum dots (PQDs) with an average size of 2.6 ± 0.9 nm using a liquid exfoliation method involving ultrasound probe sonication followed by bath sonication. By coupling the as-prepared PQDs with microfiber evanescent light field, the PQD-based saturable absorber (SA) device exhibits ultrafast nonlinear saturable absorption property, with an optical modulation depth of 8.1% at the telecommunication band. With the integration of the all-fiber PQD-based SA, a continuous-wave passively mode-locked erbium-doped (Er-doped) laser cavity delivers stable, self-starting pulses with a pulse duration of 0...
February 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28211185/a-comparison-of-goldmann-iii-v-and-spatially-equated-test-stimuli-in-visual-field-testing-the-importance-of-complete-and-partial-spatial-summation
#6
Jack Phu, Sieu K Khuu, Barbara Zangerl, Michael Kalloniatis
PURPOSE: Goldmann size V (GV) test stimuli are less variable with a greater dynamic range and have been proposed for measuring contrast sensitivity instead of size III (GIII). Since GIII and GV operate within partial summation, we hypothesise that actual GV (aGV) thresholds could predict GIII (pGIII) thresholds, facilitating comparisons between actual GIII (aGIII) thresholds with pGIII thresholds derived from smaller GV variances. We test the suitability of GV for detecting visual field (VF) loss in patients with early glaucoma, and examine eccentricity-dependent effects of number and depth of defects...
March 2017: Ophthalmic & Physiological Optics: the Journal of the British College of Ophthalmic Opticians (Optometrists)
https://www.readbyqxmd.com/read/28210629/cellular-mechanisms-of-liver-regeneration-and-cell-based-therapies-of-liver-diseases
#7
REVIEW
Irina V Kholodenko, Konstantin N Yarygin
The emerging field of regenerative medicine offers innovative methods of cell therapy and tissue/organ engineering as a novel approach to liver disease treatment. The ultimate scientific foundation of both cell therapy of liver diseases and liver tissue and organ engineering is delivered by the in-depth studies of the cellular and molecular mechanisms of liver regeneration. The cellular mechanisms of the homeostatic and injury-induced liver regeneration are unique. Restoration of the mass of liver parenchyma is achieved by compensatory hypertrophy and hyperplasia of the differentiated parenchymal cells, hepatocytes, while expansion and differentiation of the resident stem/progenitor cells play a minor or negligible role...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28210001/visualization-of-au-nanoparticles-buried-in-a-polymer-matrix-by-scanning-thermal-noise-microscopy
#8
Atsushi Yao, Kei Kobayashi, Shunta Nosaka, Kuniko Kimura, Hirofumi Yamada
Several researchers have recently demonstrated visualization of subsurface features with a nanometer-scale resolution using various imaging schemes based on atomic force microscopy. Since all these subsurface imaging techniques require excitation of the oscillation of the cantilever and/or sample surface, it has been difficult to identify a key imaging mechanism. Here we demonstrate visualization of Au nanoparticles buried 300 nm into a polymer matrix by measurement of the thermal noise spectrum of a microcantilever with a tip in contact to the polymer surface...
February 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28208474/key-lock-colloids-in-a-nematic-liquid-crystal
#9
Nuno M Silvestre, M Tasinkevych
The Landau-de Gennes free energy is used to study theoretically the effective interaction of spherical "key" and anisotropic "lock" colloidal particles. We assume identical anchoring properties of the surfaces of the key and of the lock particles, and we consider planar degenerate and perpendicular anchoring conditions separately. The lock particle is modeled as a spherical particle with a spherical dimple. When such a particle is introduced into a nematic liquid crystal, it orients its dimple at an oblique angle θ_{eq} with respect to the far field director n_{∞}...
January 2017: Physical Review. E
https://www.readbyqxmd.com/read/28207242/surface-casing-pressure-as-an-indicator-of-well-integrity-loss-and-stray-gas-migration-in-the-wattenberg-field-colorado
#10
Greg Lackey, Harihar Rajaram, Owen A Sherwood, Troy L Burke, Joseph N Ryan
The risk of environmental contamination by oil and gas wells depends strongly on the frequency with which they lose integrity. Wells with compromised integrity typically exhibit pressure in their outermost annulus (surface casing pressure, SfCP) due to gas accumulation. SfCP is an easily measured but poorly documented gauge of well integrity. Here, we analyze SfCP data from the Colorado Oil and Gas Conservation Commission database to evaluate the frequency of well integrity loss in the Wattenberg Test Zone (WTZ), within the Wattenberg Field, Colorado...
February 16, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28199351/physiological-plasticity-related-to-zonation-affects-hsp70-expression-in-the-reef-building-coral-pocillopora-verrucosa
#11
Davide Poli, Elena Fabbri, Stefano Goffredo, Valentina Airi, Silvia Franzellitti
This study investigates for the first time the transcriptional regulation of a stress-inducible 70-kDa heat shock protein (hsp70) in the scleractinian coral Pocillopora verrucosa sampled at three locations and two depths (3 m and 12 m) in Bangka Island waters (North Sulawesi, Indonesia). Percentage of coral cover indicated reduced habitat suitability with depth and at the Tanjung Husi (TA) site, which also displayed relatively higher seawater temperatures. Expression of the P. verrucosa hsp70 transcript evaluated under field conditions followed a depth-related profile, with relatively higher expression levels in 3-m collected nubbins compared to the 12-m ones...
2017: PloS One
https://www.readbyqxmd.com/read/28199277/funding-accountable-care-in-oregon-financial-models-in-two-coordinated-care-organizations
#12
Lauren Broffman, Kristin Brown, Bruce K Bayley, Lucy Savitz, Jill Rissi
Oregon's coordinated care organizations (CCOs) are an integral part of a massive statewide reform that brings accountable care to Medicaid. CCOs are regional collaboratives among health plans, providers, county public health, and communitybased organizations that administer a single global budget covering physical, mental, and dental healthcare for low-income Oregonians. CCOs have been given freedom within the global budget to implement reforms that might capture efficiencies in cost and quality. For this study-fielded between 2012 and 2015-we traced the path of the global budget through the interior structures of two of Oregon's most promising CCOs...
July 2016: Journal of Healthcare Management / American College of Healthcare Executives
https://www.readbyqxmd.com/read/28198902/microvalve-based-bioprinting-process-bio-inks-and-applications
#13
REVIEW
Wei Long Ng, Jia Min Lee, Wai Yee Yeong, May Win Naing
Bioprinting is an emerging research field that has attracted tremendous attention for various applications; it offers a highly automated, advanced manufacturing platform for the fabrication of complex bioengineered constructs. Different bio-inks comprising multiple types of printable biomaterials and cells are utilized during the bioprinting process to improve the homology to native tissues and/or organs in a highly reproducible manner. This paper, presenting a first-time comprehensive yet succinct review of microvalve-based bioprinting, provides an in-depth analysis and comparison of different drop-on-demand bioprinting systems and highlights the important considerations for microvalve-based bioprinting systems...
February 15, 2017: Biomaterials Science
https://www.readbyqxmd.com/read/28198591/interpenetrating-conducting-hydrogel-materials-for-neural-interfacing-electrodes
#14
Josef Goding, Aaron Gilmour, Penny Martens, Laura Poole-Warren, Rylie Green
Conducting hydrogels (CHs) are an emerging technology in the field of medical electrodes and brain-machine interfaces. The greatest challenge to the fabrication of CH electrodes is the hybridization of dissimilar polymers (conductive polymer and hydrogel) to ensure the formation of interpenetrating polymer networks (IPN) required to achieve both soft and electroactive materials. A new hydrogel system is developed that enables tailored placement of covalently immobilized dopant groups within the hydrogel matrix...
February 15, 2017: Advanced Healthcare Materials
https://www.readbyqxmd.com/read/28197584/nanoscale-tailor-made-membranes-for-precise-and-rapid-molecular-sieve-separation
#15
Jing Wang, Junyong Zhu, Yatao Zhang, Jindun Liu, Bart Van der Bruggen
The precise and rapid separation of different molecules from aqueous, organic solutions and gas mixtures is critical to many technologies in the context of resource-saving and sustainable development. The strength of membrane-based technologies is well recognized and they are extensively applied as cost-effective, highly efficient separation techniques. Currently, empirical-based approaches, lacking an accurate nanoscale control, are used to prepare the most advanced membranes. In contrast, nanoscale control renders the membrane molecular specificity (sub-2 nm) necessary for efficient and rapid molecular separation...
February 15, 2017: Nanoscale
https://www.readbyqxmd.com/read/28196453/near-infrared-spectroscopy-in-gait-disorders
#16
Vera Gramigna, Giovanni Pellegrino, Antonio Cerasa, Simone Cutini, Roberta Vasta, Giuseppe Olivadese, Iolanda Martino, Aldo Quattrone
Walking is a complex motor behavior with a special relevance in clinical neurology. Many neurological diseases, such as Parkinson's disease and stroke, are characterized by gait disorders whose neurofunctional correlates are poorly investigated. Indeed, the analysis of real walking with the standard neuroimaging techniques poses strong challenges, and only a few studies on motor imagery or walking observation have been performed so far. Functional near-infrared spectroscopy (fNIRS) is becoming an important research tool to assess functional activity in neurological populations or for special tasks, such as walking, because it allows investigating brain hemodynamic activity in an ecological setting, without strong immobility constraints...
January 1, 2017: Neurorehabilitation and Neural Repair
https://www.readbyqxmd.com/read/28196095/depth-dependent-flow-and-pressure-characteristics-in-cortical-microvascular-networks
#17
Franca Schmid, Philbert S Tsai, David Kleinfeld, Patrick Jenny, Bruno Weber
A better knowledge of the flow and pressure distribution in realistic microvascular networks is needed for improving our understanding of neurovascular coupling mechanisms and the related measurement techniques. Here, numerical simulations with discrete tracking of red blood cells (RBCs) are performed in three realistic microvascular networks from the mouse cerebral cortex. Our analysis is based on trajectories of individual RBCs and focuses on layer-specific flow phenomena until a cortical depth of 1 mm. The individual RBC trajectories reveal that in the capillary bed RBCs preferentially move in plane...
February 14, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28195025/the-depth-of-fields-managing-focus-in-the-epistemic-subcultures-of-mind-and-brain-science
#18
David Peterson
The 'psy' sciences emerged from the tangled roots of philosophy, physiology, biology and medicine, and these origins have produced heterogeneous fields. Scientists in these areas work in a complex, overlapping ecology of fields that results in the constant co-presence of dissonant theories, methods and research objects. This raises questions regarding how conceptual clarity is maintained. Using the optical metaphor 'depth of field', I show how researchers in all fields marginalize potential threats to routine scientific work by framing them as either too broad and imprecise or too narrow and technical...
February 2017: Social Studies of Science
https://www.readbyqxmd.com/read/28194649/numerical-modeling-of-percutaneous-auricular-vagus-nerve-stimulation-a-realistic-3d-model-to-evaluate-sensitivity-of-neural-activation-to-electrode-position
#19
Amine M Samoudi, Stefan Kampusch, Emmeric Tanghe, Jozsef C Széles, Luc Martens, Eugenijus Kaniusas, Wout Joseph
OBJECTIVE: Percutaneous stimulation of the auricular branch of the vagus nerve (pVNS) by miniaturized needle electrodes in the auricle gained importance as a treatment for acute and chronic pain. The objective is to establish a realistic numerical model of pVNS and investigate the effects of stimulation waveform, electrodes' depth, and electrodes' position on nerve excitation threshold and the percentage of stimulated nerves. METHODS: Simulations were performed with Sim4Life...
February 13, 2017: Medical & Biological Engineering & Computing
https://www.readbyqxmd.com/read/28192950/large-o2-cluster-ions-as-sputter-beam-for-tof-sims-depth-profiling-of-alkali-metals-in-thin-sio2-films
#20
Sabine Holzer, Stefan Krivec, Sven Kayser, Julia Zakel, Herbert Hutter
A sputter beam, consisting of large O2 clusters, was used to record depth profiles of alkali metal ions (Me(+)) within thin SiO2 layers. The O2 gas cluster ion beam (O2-GCIB) exhibits an erosion rate comparable to the frequently used O2(+) projectiles. However, because of its high sputter yield the necessary beam current is considerably lower (factor 50), resulting in a decreased amount of excess charges at the SiO2 surface. Hence, a reduced electric field is obtained within the remaining dielectric layer. This drastically mitigates the Me(+) migration artifact, commonly observed in depth profiles of various dielectric materials, if analyzed by time-of-flight secondary ion mass spectrometry (ToF-SIMS) in dual beam mode...
February 9, 2017: Analytical Chemistry
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