keyword
MENU ▼
Read by QxMD icon Read
search

multiphoton

keyword
https://www.readbyqxmd.com/read/29348200/active-learning-machine-learns-to-create-new-quantum-experiments
#1
Alexey A Melnikov, Hendrik Poulsen Nautrup, Mario Krenn, Vedran Dunjko, Markus Tiersch, Anton Zeilinger, Hans J Briegel
How useful can machine learning be in a quantum laboratory? Here we raise the question of the potential of intelligent machines in the context of scientific research. A major motivation for the present work is the unknown reachability of various entanglement classes in quantum experiments. We investigate this question by using the projective simulation model, a physics-oriented approach to artificial intelligence. In our approach, the projective simulation system is challenged to design complex photonic quantum experiments that produce high-dimensional entangled multiphoton states, which are of high interest in modern quantum experiments...
January 18, 2018: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/29345326/live-animal-imaging-of-renal-function-by-multiphoton-microscopy
#2
Kenneth W Dunn, Timothy A Sutton, Ruben M Sandoval
Intravital microscopy, microscopy of living animals, is a powerful research technique that combines the resolution and sensitivity found in microscopic studies of cultured cells with the relevance and systemic influences of cells in the context of the intact animal. The power of intravital microscopy has recently been extended with the development of multiphoton fluorescence microscopy systems capable of collecting optical sections from deep within the kidney at subcellular resolution, supporting high-resolution characterizations of the structure and function of glomeruli, tubules, and vasculature in the living kidney...
January 18, 2018: Current Protocols in Cytometry
https://www.readbyqxmd.com/read/29340409/dynamics-of-3d-carcinoma-cell-invasion-into-aligned-collagen
#3
Arja Ray, Rachel K Morford, Nima Ghaderi, David J Odde, Paolo P Provenzano
Carcinoma cells frequently expand and invade from a confined lesion, or multicellular clusters, into and through the stroma on the path to metastasis, often with an efficiency dictated by the architecture and composition of the microenvironment. Specifically, in desmoplastic carcinomas such as those of the breast, aligned collagen tracks provide contact guidance cues for directed cancer cell invasion. Yet, the evolving dynamics of this process of invasion remains poorly understood, in part due to difficulties in continuously capturing both spatial and temporal heterogeneity and progression to invasion in experimental systems...
January 17, 2018: Integrative Biology: Quantitative Biosciences From Nano to Macro
https://www.readbyqxmd.com/read/29337539/a-comparative-irmpd-and-dft-study-of-fe3-and-uo22-complexation-with-n-methylacetohydroxamic-acid
#4
Thibault Terencio, Jana Roithová, Stéphane Brandès, Yoann Rousselin, Marie-José Penouilh, Michel Meyer
Iron(III) and uranyl complexes of N-methylacetohydroxamic acid (NMAH) have been investigated by mass spectrometry, infrared multiphoton dissociation (IRMPD) spectroscopy, and density functional theory (DFT) calculations. A comparison between IRMPD and theoretical IR spectra enabled one to probe the structures for some selected complexes detected in the gas phase. The results show that coordination of Fe3+ and UO22+ by hydroxamic acid is of a very similar nature. Natural bond orbital analysis suggests that bonding in uranyl complexes possesses a slightly stronger ionic character than that in iron complexes...
January 16, 2018: Inorganic Chemistry
https://www.readbyqxmd.com/read/29335697/photodissociation-dynamics-of-bromoiodomethane-from-the-first-and-second-absorption-bands-a-combined-velocity-map-and-slice-imaging-study
#5
Sonia Marggi Poullain, David V Chicharro, Eduardo Navarro, Luis Rubio-Lago, Jesús González-Vázquez, Luis Bañares
The photodissociation dynamics of bromoiodomethane (CH2BrI) have been investigated at the maximum of the first A and second A' absorption bands, at 266 and 210 nm excitation wavelengths, respectively, using velocity map and slice imaging techniques in combination with a probe detection of both iodine and bromine fragments, I(2P3/2), I*(2P1/2), Br(2P3/2) and Br*(2P1/2) via (2 + 1) resonance enhanced multiphoton ionization. Experimental results, i.e. translational energy and angular distributions, are reported and discussed in conjunction with high level ab initio calculations of potential energy curves and absorption spectra...
January 16, 2018: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29335679/deep-tissue-imaging-with-multiphoton-fluorescence-microscopy
#6
David R Miller, Jeremy W Jarrett, Ahmed M Hassan, Andrew K Dunn
We present a review of imaging deep-tissue structures with multiphoton microscopy. We examine the effects of light scattering and absorption due to the optical properties of biological sample and identify 1,300 nm and 1,700 nm as ideal excitation wavelengths. We summarize the availability of fluorophores for multiphoton microscopy as well as ultrafast laser sources to excite available fluorophores. Lastly, we discuss the applications of multiphoton microscopy for neuroscience.
December 2017: Current Opinion in Biomedical Engineering
https://www.readbyqxmd.com/read/29333748/near-infrared-light-sensitive-polyvinyl-alcohol-hydrogel-photoresist-for-spatiotemporal-control-of-cell-instructive-3d-microenvironments
#7
Xiao-Hua Qin, Xiaopu Wang, Markus Rottmar, Bradley J Nelson, Katharina Maniura-Weber
Advanced hydrogel systems that allow precise control of cells and their 3D microenvironments are needed in tissue engineering, disease modeling, and drug screening. Multiphoton lithography (MPL) allows true 3D microfabrication of complex objects, but its biological application requires a cell-compatible hydrogel resist that is sufficiently photosensitive, cell-degradable, and permissive to support 3D cell growth. Here, an extremely photosensitive cell-responsive hydrogel composed of peptide-crosslinked polyvinyl alcohol (PVA) is designed to expand the biological applications of MPL...
January 15, 2018: Advanced Materials
https://www.readbyqxmd.com/read/29332391/interconversion-of-methyltropyl-and-xylyl-radicals-a-pathway-unavailable-to-the-benzyl-tropyl-rearrangement
#8
Neil James Reilly, Gabriel da Silva, Callan M Wilcox, Zijun Ge, Damian L Kokkin, Tyler P Troy, Klaas Nauta, Scott H Kable, Michael C McCarthy, Timothy W Schmidt
The products of an electrical discharge containing toluene are interrogated using resonance-enhanced multiphoton ionization and laser-induced fluorescence spectroscopies. A previously unreported electronic spectrum recorded at m/z = 105, with a putative origin band at 26053 cm-1, is assigned to methyltropyl radical, which appears to be a major product of the toluene discharge, plausibly arising from CH insertion. All three o-, m- and p-xylyl isomers are also identified. These isomers are detected in electrical discharges containing various xylenes, where it is also found that interconversion occurs: A discharge of o-xylene produces some m-xylyl; a discharge of m-xylene produces some o-xylyl; and a discharge of p-xylene produces all three isomers...
January 15, 2018: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/29332131/assessment-of-human-corneas-prior-to-transplantation-using-high-resolution-two-photon-imaging
#9
Ana Batista, Hans Georg Breunig, Aisada König, Andreas Schindele, Tobias Hager, Berthold Seitz, António Miguel Morgado, Karsten König
Purpose: The purpose of this study was to evaluate the feasibility of using two-photon imaging (TPI) to assess the condition of human corneas for transplantation. Methods: Human corneas were imaged after different storage times: short-term (STS), medium-term (MTS), and long-term (LTS) storage. A high-resolution, custom-built 5-dimensional multiphoton microscope with 12-fs pulsed laser excitation was used for image acquisition. Results: Optical discrimination between different corneal layers and sublayers based on their morphologic characteristics revealed by two-photon autofluorescence (AF) is possible...
January 1, 2018: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/29328723/second-order-temporal-interference-with-thermal-light-interference-beyond-the-coherence-time
#10
Yong Sup Ihn, Yosep Kim, Vincenzo Tamma, Yoon-Ho Kim
We report the observation of a counterintuitive phenomenon in multipath correlation interferometry with thermal light. The intensity correlation between the outputs of two unbalanced Mach-Zehnder interferometers (UMZIs) with two classically correlated beams of thermal light at the input exhibits genuine second-order interference with the visibility of 1/3. Surprisingly, the second-order interference does not degrade at all no matter how much the path length difference in each UMZI is increased beyond the coherence length of the thermal light...
December 29, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/29328248/filamentation-free-self-compression-of-mid-infrared-pulses-in-birefringent-crystals-with-second-order-cascading-enhanced-self-focusing-nonlinearity
#11
Rosvaldas Šuminas, Gintaras Tamošauskas, Audrius Dubietis
We experimentally demonstrate virtually lossless, filamentation-free and energy-scalable more than three-fold self-compression of mid-infrared laser pulses at 2.1 μm in a birefringent medium (β-BBO crystal), which stems from favorable interplay between the second-order cascading-enhanced self-phase modulation and anomalous group velocity dispersion. By choosing an appropriate input beam diameter and intensity, the self-compression down to sub-30 fs pulse widths with gigawatt peak power is achieved without the onset of beam filamentation and associated nonlinear losses due to the multiphoton absorption, yielding the energy throughput greater than 86%...
January 15, 2018: Optics Letters
https://www.readbyqxmd.com/read/29327927/atom-dependent-edge-enhanced-second-harmonic-generation-on-mos2-monolayers
#12
Kuang-I Lin, Yen-Hung Ho, Shu-Bai Liu, Jian-Jhih Ciou, Bo-Ting Huang, Christopher Chen, Han-Ching Chang, Chien-Liang Tu, Chang-Hsiao Chen
Edge morphology and lattice orientation of single-crystal molybdenum disulfide (MoS2) monolayers, a transition metal dichalcogenide (TMD), possessing a triangular shape with different edges grown by chemical vapor deposition are characterized by atomic force microscopy and transmission electron microscopy. Multiphoton laser scanning microscopy is utilized to study one-dimensional atomic edges of MoS2 monolayers with localized mid-gap electronic states, which result in greatly enhanced optical second-harmonic generation (SHG)...
January 12, 2018: Nano Letters
https://www.readbyqxmd.com/read/29319936/submucosal-gland-mucus-strand-velocity-is-decreased-in-chronic-rhinosinusitis
#13
Kiranya E Tipirneni, Shaoyan Zhang, Do-Yeon Cho, Jessica Grayson, Daniel F Skinner, Calvin Mackey, Lindsay Moore, Denzel Cole, Catherine G Banks, Bradford A Woodworth
BACKGROUND: Chronic rhinosinusitis (CRS) may be initiated by innately impaired host defense mechanisms that predispose the upper airways to infection. Recent evidence suggests tethering of submucosal gland mucus strands represents an inciting event within cystic fibrosis (CF) airways, occurring prior to onset of chronic infection. Submucosal gland hypertrophy and defective mucociliary clearance (MCC) are present in actively inflamed sinuses, but mucus strand velocity may also be affected as a secondary event, further contributing to chronic disease...
January 10, 2018: International Forum of Allergy & Rhinology
https://www.readbyqxmd.com/read/29314303/infrared-multiphoton-dissociation-spectroscopy-with-free-electron-lasers-on-the-road-from-small-molecules-to-biomolecules
#14
Lucie Jasikova, Jana Roithová
Infrared multiphoton dissociation (IRMPD) spectroscopy is commonly used to determine the structure of isolated, mass-selected ions in the gas phase. This method has been widely used since it became available at multi-user free-electron laser (FEL) facilities. Thus, in this minireview, we examine the use of IRMPD/FEL spectroscopy for investigating ions derived from small molecules, metal complexes and organometallic compounds and biorelevant ions. Furthermore, we outline new applications of IRMPD spectroscopy to the study of biomolecules...
January 3, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29311591/segmented-cell-analyses-to-measure-redox-states-of-autofluorescent-nad-p-h-fad-trp-in-cancer-cells-by-flim
#15
Horst Wallrabe, Zdenek Svindrych, Shagufta R Alam, Karsten H Siller, Tianxiong Wang, David Kashatus, Song Hu, Ammasi Periasamy
Multiphoton FLIM microscopy offers many opportunities to investigate processes in live cells, tissue and animal model systems. For redox measurements, FLIM data is mostly published by cell mean values and intensity-based redox ratios. Our method is based entirely on FLIM parameters generated by 3-detector time domain microscopy capturing autofluorescent signals of NAD(P)H, FAD and novel FLIM-FRET application of Tryptophan and NAD(P)H-a2%/FAD-a1% redox ratio. Furthermore, image data is analyzed in segmented cells thresholded by 2 × 2 pixel Regions of Interest (ROIs) to separate mitochondrial oxidative phosphorylation from cytosolic glycolysis in a prostate cancer cell line...
January 8, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29306282/imaging-spectroscopy-of-the-missing-rempi-bands-of-methyl-radicals-final-touches-on-all-vibrational-frequencies-of-the-3p-rydberg-states
#16
Huilin Pan, Kopin Liu
(2 + 1) resonance-enhanced multiphoton ionization (REMPI) detection of methyl radicals, in particular that via the intermediate 3p Rydberg states, has shown to be a powerful method and thus enjoyed a wide range of applications. Methyl has six vibrational modes. Among them-including partially and fully deuterated isotopologs-four out of twenty vibrational frequencies in the intermediate 3p states have so far eluded direct spectroscopic determination. Here, by exploiting the imaging spectroscopy approach to a few judiciously selected chemical reactions, the four long-sought REMPI bands-CHD2(611), CH2D(311), CH2D(511), and CH2D(611)-are discovered, which complete the REMPI identification for probing any vibrational mode of excitation of methyl radical and its isotopologs...
January 7, 2018: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29303582/spectroscopic-study-of-a-photoactive-antibacterial-agent-2-3-distyrylindole
#17
Ruwini Dinushika Rajapaksha, Matthias Banet, Cody Champion, Liliya V Frolova, Snezna Rogelj, Pabitra Choudhury, Mahinda Iroshana Ranasinghe
Optical properties and fluorescence decay dynamics of a photoactive indole based antibacterial chromophore system, 2, 3-distyrylindole (23DSI), was investigated using various spectroscopic characterization techniques. These studies were done by utilizing the steady state UV-Vis spectroscopy, the steady state fluorescence spectroscopy, the time-resolve fluorescence upconversion spectroscopy, and time correlated single photon counting spectroscopy as experiment techniques. Our studies show that the 23DSI molecule has a multiphoton absorbing property as indicated by two and three photon absorption in both solution and solid phases...
January 5, 2018: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/29300411/customizing-polyelectrolyte-complex-shapes-through-photolithographic-directed-assembly
#18
Udaka K de Silva, Kunal Choudhuri, Amanda C Bryant-Friedrich, Yakov Lapitsky
Polyelectrolyte complexes (PECs) form through the association of oppositely charged polymers and, due to their attractive properties, such as their mild/simple preparation and stimulus-sensitivity, attract widespread interest. The diverse applications of these materials often require control over PEC shapes. As a versatile approach to achieving such control, we report a new photolithographic directed assembly method for tailoring their structure. This method uses aqueous solutions of a polyelectrolyte, an oppositely charged monomer and a photoinitiator...
January 4, 2018: Soft Matter
https://www.readbyqxmd.com/read/29289926/the-use-of-suction-blisters-to-measure-sunscreen-protection-against-uvr-induced-dna-damage
#19
Gwendal Josse, Thierry Douki, Jimmy Le Digabel, Eleonore Gravier, Emmanuel Questel
The formation of DNA photoproducts caused by solar UVR exposure needs to be investigated in-vivo and in particular in order to assess sunscreens' level of protection against solar genotoxicity. The study's purposes were: i) to evaluate if the roof of suction blisters is an appropriate sampling method for measuring photoproducts, and ii) to measure in-vivo sunscreen protection against cyclobutane pyrimidine dimers. Skin areas on the interior forearms of eight healthy volunteers were exposed in-vivo to 2 MED of simulated solar radiation (SSR) and to 15 MED on a sunscreen protected area...
December 22, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/29287105/effect-of-intra-articular-administration-of-superparamagnetic-iron-oxide-nanoparticles-spions-for-mri-assessment-of-the-cartilage-barrier-in-a-large-animal-model
#20
Raphael Labens, Carola Daniel, Sarah Hall, Xin-Rui Xia, Tobias Schwarz
Early diagnosis of cartilage disease at a time when changes are limited to depletion of extracellular matrix components represents an important diagnostic target to reduce patient morbidity. This report is to present proof of concept for nanoparticle dependent cartilage barrier imaging in a large animal model including the use of clinical magnetic resonance imaging (MRI). Conditioned (following matrix depletion) and unconditioned porcine metacarpophalangeal cartilage was evaluated on the basis of fluorophore conjugated 30 nm and 80 nm spherical gold nanoparticle permeation and multiphoton laser scanning and bright field microscopy after autometallographic particle enhancement...
2017: PloS One
keyword
keyword
15078
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"