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https://www.readbyqxmd.com/read/28934254/deep-reconstruction-model-for-dynamic-pet-images
#1
Jianan Cui, Xin Liu, Yile Wang, Huafeng Liu
Accurate and robust tomographic reconstruction from dynamic positron emission tomography (PET) acquired data is a difficult problem. Conventional methods, such as the maximum likelihood expectation maximization (MLEM) algorithm for reconstructing the activity distribution-based on individual frames, may lead to inaccurate results due to the checkerboard effect and limitation of photon counts. In this paper, we propose a stacked sparse auto-encoder based reconstruction framework for dynamic PET imaging. The dynamic reconstruction problem is formulated in a deep learning representation, where the encoding layers extract the prototype features, such as edges, so that, in the decoding layers, the reconstructed results are obtained through a combination of those features...
2017: PloS One
https://www.readbyqxmd.com/read/28934227/hemorrhage-enhances-cytokine-complement-component-3-and-caspase-3-and-regulates-micrornas-associated-with-intestinal-damage-after-whole-body-gamma-irradiation-in-combined-injury
#2
Juliann G Kiang, Joan T Smith, Marsha N Anderson, Thomas B Elliott, Paridhi Gupta, Nagaraja S Balakathiresan, Radha K Maheshwari, Barbara Knollmann-Ritschel
Hemorrhage following whole-body γ-irradiation in a combined injury (CI) model increases mortality compared to whole-body γ-irradiation alone (RI). The decreased survival in CI is accompanied by increased bone marrow injury, decreased hematocrit, and alterations of miRNA in the kidney. In this study, our aim was to examine cytokine homeostasis, susceptibility to systemic bacterial infection, and intestinal injury. More specifically, we evaluated the interleukin-6 (IL-6)-induced stress proteins including C-reactive protein (CRP), complement 3 (C3), Flt-3 ligand, and corticosterone...
2017: PloS One
https://www.readbyqxmd.com/read/28933857/giant-enhancement-of-cathodoluminescence-of-monolayer-transitional-metal-dichalcogenides-semiconductors
#3
Shoujun Zheng, Jinkyu So, Fucai Liu, Zheng Liu, Nikolay I Zheludev, Hong Jin Fan
Monolayer two-dimensional transitional metal dichalcogenides, such as MoS2, WS2 and WSe2, are direct band gap semiconductors with large exciton binding energy. They attract growing attentions for opto-electronic applications including solar cells, photo-detectors, light-emitting diodes and photo-transistors, capacitive energy storage, photodynamic cancer therapy and sensing on flexible platforms. While light-induced luminescence has been widely studied, luminescence induced by injection of free electrons could promise another important applications of these new materials...
September 21, 2017: Nano Letters
https://www.readbyqxmd.com/read/28933852/entangled-two-photon-absorption-cross-section-on-the-808-nm-region-for-the-common-dyes-zinc-tetraphenylporphyrin-and-rhodamine-b
#4
Juan Pablo Villabona-Monsalve, Omar Calderón-Losada, Mayerlin Nunez Portela, Alejandra Valencia
We report the measurement of the entangled two photon absorption (ETPA) cross section, σΕ , at 808 nm on organic chromophores in solution in a low photon flux regime. We performed measurements on Zinc tetraphenylporphyrin (ZnTPP) in Toluene and Rhodamine B (RhB) in Methanol. This is, to the best of our knowledge, the first time that σΕ is measured for RhB. Additionally, we report a study of the dependence of σΕ on the molecular concentration for both molecular systems. In contrast to previous experiments, our measurements are based on detecting the pairs of photons that are transmitted by the molecular system...
September 21, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28933480/two-photon-spectroscopy-of-tungsten-0-arylisocyanides-using-nanosecond-pulsed-excitation
#5
Kana Takematsu, Sara A M Wehlin, Wesley Sattler, Jay R Winkler, Harry B Gray
The two-photon absorption (TPA) cross sections (δ) for tungsten(0) arylisocyanides (W(CNAr)6) were determined in the 800-1000 nm region using two-photon luminescence (TPL) spectroscopy. The complexes have high TPA cross sections, in the range 1000-2000 GM at 811.8 nm. In comparison, the cross section at 811.8 nm for tris-(2,2'-bipyridine)ruthenium(ii), [Ru(bpy)3](2+), is 7 GM. All measurements were performed using a nanosecond-pulsed laser system.
September 21, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28933479/linking-classical-and-molecular-optomechanics-descriptions-of-sers
#6
Mikołaj K Schmidt, Ruben Esteban, Felix Benz, Jeremy J Baumberg, Javier Aizpurua
The surface-enhanced Raman scattering (SERS) of molecular species in plasmonic cavities can be described as an optomechanical process where plasmons constitute an optical cavity of reduced effective mode volume which effectively couples to the vibrations of the molecules. An optomechanical Hamiltonian can address the full quantum dynamics of the system, including the phonon population build-up, the vibrational pumping regime, and the Stokes-anti-Stokes correlations of the photons emitted. Here we describe in detail two different levels of approximation to the methodological solution of the optomechanical Hamiltonian of a generic SERS configuration, and compare the results of each model in light of recent experiments...
September 21, 2017: Faraday Discussions
https://www.readbyqxmd.com/read/28933460/tpz-a-bright-centrosymmetric-two-photon-scaffold-for-bioimaging
#7
Zuhai Lei, Ping Yue, Xueli Wang, Xinran Li, Yi Li, Haihong He, Xiao Luo, Xiangming Meng, Jinquan Chen, Xuhong Qian, Youjun Yang
The development of biocompatible two-photon fluorophores with a large absorption cross-section is challenging, despite the presence of theoretical guidelines. By rendering asymmetric PRODAN dye centrosymmetric, we designed and synthesized a novel class of two-photon fluorophores (TPZ). Their photophysical properties were investigated and their imaging potentials in cells, tissues and zebrafish were showcased.
September 21, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28933068/functional-neuroimaging-in-obesity-research
#8
Liliana Letra, Daniela Pereira, Miguel Castelo-Branco
Functional neuroimaging is beginning to yield valuable insights into the neurobiological underpinnings of the effects of obesity on neural circuits. Functional magnetic resonance imaging (fMRI), positron emission tomography (PET), and single-photon emission computed tomography (SPECT) studies have been used to identify aberrant activation patterns in regions implicated in reward (e.g., striatum, orbitofrontal cortex, insula), emotion and memory (e.g., amygdala, hippocampus), sensory and motor processing (e...
2017: Advances in Neurobiology
https://www.readbyqxmd.com/read/28932931/usefulness-of-zebrafish-larvae-to-evaluate-drug-induced-functional-and-morphological-renal-tubular-alterations
#9
Rita Gorgulho, Raquel Jacinto, Susana S Lopes, Sofia A Pereira, Erin M Tranfield, Gabriel G Martins, Emilio J Gualda, Rico J E Derks, Ana C Correia, Evelyne Steenvoorden, Petra Pintado, Oleg A Mayboroda, Emilia C Monteiro, Judit Morello
Prediction and management of drug-induced renal injury (DIRI) rely on the knowledge of the mechanisms of drug insult and on the availability of appropriate animal models to explore it. Zebrafish (Danio rerio) offers unique advantages for assessing DIRI because the larval pronephric kidney has a high homology with its human counterpart and it is fully mature at 3.5 days post-fertilization. Herein, we aimed to evaluate the usefulness of zebrafish larvae as a model of renal tubular toxicity through a comprehensive analysis of the renal alterations induced by the lethal concentrations for 10% of the larvae for gentamicin, paracetamol and tenofovir...
September 20, 2017: Archives of Toxicology
https://www.readbyqxmd.com/read/28932820/reduced-arterial-elasticity-due-to-surgical-skeletonization-is-ameliorated-by-abluminal-peg-hydrogel
#10
Karyn G Robinson, Rebecca A Scott, Anne M Hesek, Edward J Woodford, Wafa Amir, Thomas A Planchon, Kristi L Kiick, Robert E Akins
Arteries for bypass grafting are harvested either with neighboring tissue attached or as skeletonized vessels that are free of surrounding tissue. There are significant benefits to skeletonization, but reports suggest that skeletonized vessels may develop structural defects and are at risk for atherosclerosis. We investigated the specific short-term effects of skeletonization on carotid artery biomechanics and microanatomy in a rabbit model. Six carotid arteries were surgically skeletonized. To support healing, three of these received polyethylene glycol hydrogel injected along their exterior surfaces...
June 2017: Bioengineering & Translational Medicine
https://www.readbyqxmd.com/read/28932670/the-way-towards-ultrafast-growth-of-single-crystal-graphene-on-copper
#11
REVIEW
Zhihong Zhang, Xiaozhi Xu, Lu Qiu, Shaoxin Wang, Tianwei Wu, Feng Ding, Hailin Peng, Kaihui Liu
The exceptional properties of graphene make it a promising candidate in the development of next-generation electronic, optoelectronic, photonic and photovoltaic devices. A holy grail in graphene research is the synthesis of large-sized single-crystal graphene, in which the absence of grain boundaries guarantees its excellent intrinsic properties and high performance in the devices. Nowadays, most attention has been drawn to the suppression of nucleation density by using low feeding gas during the growth process to allow only one nucleus to grow with enough space...
September 2017: Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
https://www.readbyqxmd.com/read/28932168/the-structural-coloration-of-textile-materials-using-self-assembled-silica-nanoparticles
#12
Weihong Gao, Muriel Rigout, Huw Owens
The work presented investigates how to produce structural colours on textile materials by applying a surface coating of silica nanoparticles (SNPs). Uniform SNPs with particle diameters in a controlled micron size range (207-350 nm) were synthesized using a Stöber-based solvent varying (SV) method which has been reported previously. Photonic crystals (PCs) were formed on the surface of a piece of textile fabric through a process of natural sedimentation self-assembly of the colloidal suspension containing uniform SNPs...
2017: Journal of Nanoparticle Research: An Interdisciplinary Forum for Nanoscale Science and Technology
https://www.readbyqxmd.com/read/28931903/plasmonic-enhancement-of-selective-photonic-virus-inactivation
#13
Mina Nazari, Min Xi, Sarah Lerch, M H Alizadeh, Chelsea Ettinger, Hisashi Akiyama, Christopher Gillespie, Suryaram Gummuluru, Shyamsunder Erramilli, Björn M Reinhard
Femtosecond (fs) pulsed laser irradiation techniques have attracted interest as a photonic approach for the selective inactivation of virus contaminations in biological samples. Conventional pulsed laser approaches require, however, relatively long irradiation times to achieve a significant inactivation of virus. In this study, we investigate the enhancement of the photonic inactivation of Murine Leukemia Virus (MLV) via 805 nm femtosecond pulses through gold nanorods whose localized surface plasmon resonance overlaps with the excitation laser...
September 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28931854/robust-magnon-photon-coupling-in-a-planar-geometry-hybrid-of-inverted-split-ring-resonator-and-yig-film
#14
Biswanath Bhoi, Bosung Kim, Junhoe Kim, Young-Jun Cho, Sang-Koog Kim
We experimentally demonstrate strongly enhanced coupling between excited magnons in an Yttrium Iron Garnet (YIG) film and microwave photons in an inverted pattern of split-ring resonator (noted as ISRR). The anti-crossing effects of the ISRR's photon mode and the YIG's magnon modes were found from |S21|-versus-frequency measurements for different strengths and directions of externally applied magnetic fields. The spin-number-normalized coupling strength (i.e. single spin-photon coupling) [Formula: see text] was determined to 0...
September 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28931844/calibrated-link-budget-of-a-silicon-photonics-wdm-transceiver-with-soa-and-semiconductor-mode-locked-laser
#15
Alvaro Moscoso-Mártir, Juliana Müller, Elmira Islamova, Florian Merget, Jeremy Witzens
Based on the single channel characterization of a Silicon Photonics (SiP) transceiver with Semiconductor Optical Amplifier (SOA) and semiconductor Mode-Locked Laser (MLL), we evaluate the optical power budget of a corresponding Wavelength Division Multiplexed (WDM) link in which penalties associated to multi-channel operation and the management of polarization diversity are introduced. In particular, channel cross-talk as well as Cross Gain Modulation (XGM) and Four Wave Mixing (FWM) inside the SOA are taken into account...
September 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28931815/silicon-single-photon-avalanche-diodes-with-nano-structured-light-trapping
#16
Kai Zang, Xiao Jiang, Yijie Huo, Xun Ding, Matthew Morea, Xiaochi Chen, Ching-Ying Lu, Jian Ma, Ming Zhou, Zhenyang Xia, Zongfu Yu, Theodore I Kamins, Qiang Zhang, James S Harris
Silicon single-photon avalanche detectors are becoming increasingly significant in research and in practical applications due to their high signal-to-noise ratio, complementary metal oxide semiconductor compatibility, room temperature operation, and cost-effectiveness. However, there is a trade-off in current silicon single-photon avalanche detectors, especially in the near infrared regime. Thick-junction devices have decent photon detection efficiency but poor timing jitter, while thin-junction devices have good timing jitter but poor efficiency...
September 20, 2017: Nature Communications
https://www.readbyqxmd.com/read/28931769/evaluation-of-early-phase-biodistribution-in-123-i-ioflupane-spect
#17
Masaki Takahashi, Shoichi Toki, Yukitaka Yamashita, Akihiro Kaneko
It is reported that pharmacokinetics after intravenous injection of (123)I-ioflupane may reflect cerebral blood flow. In this study, the early-phase pharmacokinetics of (123)I-ioflupane in 10 healthy volunteers was analyzed over time using dynamic single-photon emission computed tomography (SPECT) immediately after intravenous injection. We also examined the correlation between the (123)I-IMP imaging and the (123)I-ioflupane early-phase image for 14 cases in which both dopamine transporter (DaT) imaging by (123)I-ioflupane and cerebral blood flow imaging by (123)I-IMP were performed on the same camera...
2017: Nihon Hoshasen Gijutsu Gakkai Zasshi
https://www.readbyqxmd.com/read/28931608/non-uniform-surround-suppression-of-visual-responses-in-mouse-v1
#18
Jason M Samonds, Berquin D Feese, Tai Sing Lee, Sandra Kuhlman
Complex receptive field characteristics, distributed across a population of neurons, are thought to be critical for solving perceptual inference problems that arise during motion and image segmentation. For example, in a class of neurons referred to as 'end-stopped', increasing the length of stimuli outside of the bar-responsive region into the surround suppresses responsiveness. It is unknown whether these properties exist for receptive field surrounds in the mouse. We examined surround modulation in layer 2/3 neurons of the primary visual cortex in mice using two-photon calcium imaging...
September 20, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28930618/enhancement-of-biomass-and-phycocyanin-content-of-spirulina-platensis
#19
Mahammed Ilyas Khazi, Zeliha Demirel, Meltem Conk Dalay
Response surface methodology (RSM) based on the 2(3) factorial central composite design (CCD) was employed to evaluate optimum culture conditions (temperature, light irradiance and agitation) to enhance biomass and phycocyanin content of Spirulina platensis. The predicted maximum biomass and phycocyanin content by RSM was 1.06 g L(-1) and 107 mg L(-1), respectively, whereas maximum biomass and phycocyanin content of 1.32 g L(-1) and 127 mg L(-1) was obtained in the validation experiments under optimized conditions after 10 days of cultivation...
January 1, 2018: Frontiers in Bioscience (Elite Edition)
https://www.readbyqxmd.com/read/28930582/hypothesis-on-interactions-of-macromolecules-based-on-molecular-vibration-patterns-in-cells-and-tissues
#20
Werner Jaross
The molecular vibration patterns of structure-forming macromolecules in the living cell create very specific electromagnetic frequency patterns which might be used for information on spatial position in the three-dimensional structure as well as the chemical characteristics. Chemical change of a molecule results in a change of the vibration pattern and thus in a change of the emitted electromagnetic frequency pattern. These patterns have to be received by proteins responsible for the necessary interactions and functions...
January 1, 2018: Frontiers in Bioscience (Landmark Edition)
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