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https://www.readbyqxmd.com/read/28454173/on-the-cancellation-of-oam-beams-propagating-through-convective-turbulence
#1
Gustavo Funes, Jaime Anguita
By means of an experimental setup, we study the time evolution of orbital angular momentum (OAM) crosstalk after a 5 m propagation path with a turbulence perturbation generated by a flat heater. This convective turbulence could simulate the beam passing over hot concrete or building roofs. We study the consequences of using a wide range of transmission OAM states. We also explore the effect of misalignment, and we propose two new different techniques for analyzing the vortex cancellation. Even though results are inconsistent with theoretical predictions, especially for low turbulence regimes, we state that signal-to-noise ratio is the key factor to understanding this discrepancy...
May 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28454163/image-recovery-from-defocused-2d-fluorescent-images-in-multimodal-digital-holographic-microscopy
#2
Xiangyu Quan, Osamu Matoba, Yasuhiro Awatsuji
A technique of three-dimensional (3D) intensity retrieval from defocused, two-dimensional (2D) fluorescent images in the multimodal digital holographic microscopy (DHM) is proposed. In the multimodal DHM, 3D phase and 2D fluorescence distributions are obtained simultaneously by an integrated system of an off-axis DHM and a conventional epifluorescence microscopy, respectively. This gives us more information of the target; however, defocused fluorescent images are observed due to the short depth of field. In this Letter, we propose a method to recover the defocused images based on the phase compensation and backpropagation from the defocused plane to the focused plane using the distance information that is obtained from a 3D phase distribution...
May 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28454161/correlation-and-squeezing-for-optical-transistor-and-intensity-router-applications-in-diamond-nv-center
#3
Noor Ahmed, Ghulam Abbas Khan, Ruimin Wang, Jingru Hou, Rui Gong, Lingmeng Yang, Yanpeng Zhang
We study an optical transistor (switch and amplifier) and router by spontaneous parametric four-wave mixing and fluorescence in diamond nitrogen-vacancy (NV) center. The routing results from three peaks of fluorescence signal in the time domain, while the switching and amplification are realized by correlation and squeezing. The intensity switching speed is about 17 ns. The optical transistor and router are controlled by the power of incident beams. Our experimental results provide that the advance technique of peak division and channel equalization ratio of about 90% are applicable to all optical switching and routing...
May 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28454144/automatic-focusing-for-multisectional-objects-in-digital-holography-using-the-structure-tensor
#4
Zhenbo Ren, Ni Chen, Edmund Y Lam
Determining the axial position of the recorded object in digital holography is a crucial step for image reconstruction. When multiple discrete sections of a three-dimensional object are overlapping each other, this issue becomes more challenging. In this Letter, an autofocusing algorithm using the structure tensor and its eigenvalues is proposed. This method can extract the focal distance of each section for a multi-sectional object irrespective of whether the sections are overlapping or not. We validate the applicability of the proposed technique with synthesized and experimental data using two types of holographic systems...
May 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28454142/in-situ-sers-monitoring-of-plasmonic-nano-dopants-during-photopolymerization
#5
Ruoping Li, Yanmeng Li, Junhe Han, Mingju Huang
The motion of the plasmonic nano-dopant in photopolymers was monitored in situ and in real time using the surface-enhanced Raman scattering (SERS) technique. Here an Au@MBA@Ag (core-molecule-shell) nanoparticle colloid was synthesized to act as the nano-dopant and adsorbed 4-mercaptobenzoic acid (MBA) between the Au cells and Ag shells as the internal standard. The changes of the MBA signal closely reflect the motion of nanoparticles, since the MBA signal itself has time stability. Experimental data indicate that the optimized concentration of the nano-dopant can be obtained based on the peak intensity change of MBA at 1583  cm<sup>-1</sup>...
May 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28454140/electro-optic-sampling-of-terahertz-waves-by-laser-pulses-with-an-edge-cut-spectrum-in-birefringent-crystal
#6
I E Ilyakov, G Kh Kitaeva, B V Shishkin, R A Akhmedzhanov
We demonstrate a terahertz detection technique based on variations of the energy of femtosecond laser pulses with an edge-cut spectrum in birefringent electro-optic crystal-periodically poled lithium niobate (PPLN). The method is compared with the standard electro-optic detection scheme utilizing GaP crystal. The experimental results show that the studied technique is suited for use with birefringent crystals and allows one to achieve a much better response to the terahertz wave radiation at quasi-phase-matching frequencies of PPLN...
May 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28454074/photocatalytic-degradation-of-dye-using-ceo2-scb-composite-catalysts
#7
Duangdao Channei, Auppatham Nakaruk, Sukon Phanichphant
The main task of the present work is to enhance the photocatalytic degradation efficiency of methylene blue (MB) by using CeO2/sugarcane bagasse (SCB) composite catalysts. Homogeneous precipitation method was used to synthesis CeO2-SCB composite catalysts by adding SCB powder to precursor solution of Ce base-metal. The structural analytical data indicated the pure cubic fluorite structure of CeO2. Morphological images revealed the coating of CeO2 layer on high surface area of SCB core-shell. The chemical analysis presented spectrum of the Ce 3d in CeO2/SCB sample existed in the form of the Ce(3+) and Ce(4+) mixed- valence states...
April 22, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28454034/immobilization-of-phenanthrene-onto-gemini-surfactant-modified-sepiolite-at-solid-aqueous-interface-equilibrium-thermodynamic-and-kinetic-studies
#8
Shan Zhao, Guohe Huang, Sen Mu, Chunjiang An, Xiujuan Chen
The immobilization of phenanthrene from aqueous phase onto natural and gemini surfactant modified sepiolite was investigated with respect to contact time, pH, ionic strength and temperature. The surface modification was examined through FT-IR characterization, SEM technique, and the thermogravimetric analysis. The maximum sorption capacity of phenanthrene on modified sepiolite was 95.15μgg(-1) with initial PHE concentration 1.0mgL(-1), temperature 293K, pH7, and ionic strength 1M. The corresponding PHE removal efficiency was higher than 95%...
April 25, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28453684/mappi-dat-data-management-and-analysis-for-protein-protein-interaction-data-from-the-high-throughput-mappit-cell-microarray-platform
#9
Surya Gupta, Veronic De Puysseleyr, José Van der Heyden, Davy Maddelein, Irma Lemmens, Sam Lievens, Sven Degroeve, Jan Tavernier, Lennart Martens
Summary: Protein-protein interaction (PPI) studies have dramatically expanded our knowledge about cellular behaviour and development in different conditions. A multitude of high-throughput PPI techniques have been developed to achieve proteome-scale coverage for PPI studies, including the microarray based Mammalian Protein-Protein Interaction Trap (MAPPIT) system. Because such high-throughput techniques typically report thousands of interactions, managing and analysing the large amounts of acquired data is a challenge...
May 1, 2017: Bioinformatics
https://www.readbyqxmd.com/read/28449483/epicardial-left-atrial-appendage-closure-comparison-of-surgical-techniques-in-an-ex-vivo-model
#10
Nikolas Mirow, Sebastian Vogt, Marc Irqsusi, Rainer Moosdorf, Andreas Kirschbaum
BACKGROUND: Formation of clots in the left atrial appendage (LAA) may lead to embolism and consecutive cerebral stroke. This risk is reduced by closure and resection. To address the efficacy of surgical LAA closure, resilience to pneumatic pressure was studied. Different surgical techniques were compared in an experimental model. METHODS: From freshly slaughtered pigs cardiopulmonary preparations were taken. The left atrium was clamped airtight and the LAA was cannulated...
March 2017: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/28449038/real-time-imaging-of-single-neuronal-cell-apoptosis-in-patients-with-glaucoma
#11
Maria F Cordeiro, Eduardo M Normando, M Jorge Cardoso, Serge Miodragovic, Seham Jeylani, Benjamin M Davis, Li Guo, Sebastien Ourselin, Roger A'Hern, Philip A Bloom
Retinal cell apoptosis occurs in many ocular neurodegenerative conditions including glaucoma-the major cause of irreversible blindness worldwide. Using a new imaging technique that we have called DARC (detection of apoptosing retinal cells), which until now has only been demonstrated in animal models, we assessed if annexin 5 labelled with fluorescent dye DY-776 (ANX776) could be used safely in humans to identify retinal cell apoptosis. Eight patients with glaucomatous neurodegeneration and evidence of progressive disease, and eight healthy subjects were randomly assigned to intravenous ANX776 doses of 0...
April 26, 2017: Brain: a Journal of Neurology
https://www.readbyqxmd.com/read/28448955/ionization-spectroscopies-and-theoretical-calculations-of-cis-and-trans-3-fluoro-n-methylaniline-arn-n-1-2-van-der-waals-clusters-structures-and-binding-energies
#12
Lijuan Zhang, Dazhi Li, Min Cheng, Yikui Du, Qihe Zhu
The ab initio and dispersion-corrected density functional theory (DFT) calculations of the van der Waals (vdW) clusters of cis and trans 3-fluoro-N-methylaniline-Arn (3FNMA-Arn) (n=1,2) predict that, for cis and trans 3FNMA-Ar1 clusters, the π-bound geometry with the Ar atom sitting over the ring is the global minimum in both neutral and cationic states, while for cis and trans 3FNMA-Ar2 clusters, the [π|π]-bound sandwich structure with two Ar ligands occupying nearly equivalent π-bound positions above and below the ring plane is the global minimum...
April 18, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28448937/assessment-of-n2o-emissions-from-a-fertilised-vegetable-cropping-soil-under-different-plant-residue-management-strategies-using-15-n-tracing-techniques
#13
M Rezaei Rashti, W J Wang, C R Chen, S H Reeves, C Scheer
Combined application of plant residues and N fertilisers strongly affect soil mineral N dynamics and N2O emissions depending on the quality of the plant residues, their application methods and other management strategies. We investigated the effect of combined application of two vegetable plant residues (cauliflower and sweet corn) and (15)N fertiliser on N dynamics and N2O emission in a glasshouse pot study. The experiment was conducted under two residue management practices (soil incorporation vs surface mulching) over 98days with growing basil (Ocimum basilicum) plants...
April 24, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28448887/macro-raman-spectroscopy-for-bulk-composition-and-homogeneity-analysis-of-multi-component-pharmaceutical-powders
#14
Hui Wang, David Barona, Sulayman Oladepo, Lisa Williams, Susan Hoe, David Lechuga-Ballesteros, Reinhard Vehring
A new macro-Raman system equipped with a motorized translational sample stage and low-frequency shift capabilities was developed for bulk composition and homogeneity analysis of multi-component pharmaceutical powders. Different sampling methods including single spot and scanning measurement were compared. It was found that increasing sample volumes significantly improved the precision of quantitative composition analysis, especially for poorly mixed powders. The multi-pass cavity of the macro-Raman system increased effective sample volumes by 20 times from the sample volume defined by the collection optics, i...
April 23, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28448472/vibro-shock-dynamics-analysis-of-a-tandem-low-frequency-resonator-high-frequency-piezoelectric-energy-harvester
#15
Darius Žižys, Rimvydas Gaidys, Vytautas Ostaševičius, Birutė Narijauskaitė
Frequency up-conversion is a promising technique for energy harvesting in low frequency environments. In this approach, abundantly available environmental motion energy is absorbed by a Low Frequency Resonator (LFR) which transfers it to a high frequency Piezoelectric Vibration Energy Harvester (PVEH) via impact or magnetic coupling. As a result, a decaying alternating output signal is produced, that can later be collected using a battery or be transferred directly to the electric load. The paper reports an impact-coupled frequency up-converting tandem setup with different LFR to PVEH natural frequency ratios and varying contact point location along the length of the harvester...
April 27, 2017: Sensors
https://www.readbyqxmd.com/read/28448464/bayesian-device-free-localization-and-tracking-in-a-binary-rf-sensor-network
#16
Zhenghuan Wang, Heng Liu, Shengxin Xu, Xiangyuan Bu, Jianping An
Received-signal-strength-based (RSS-based) device-free localization (DFL) is a promising technique since it is able to localize the person without attaching any electronic device. This technology requires measuring the RSS of all links in the network constituted by several radio frequency (RF) sensors. It is an energy-intensive task, especially when the RF sensors work in traditional work mode, in which the sensors directly send raw RSS measurements of all links to a base station (BS). The traditional work mode is unfavorable for the power constrained RF sensors because the amount of data delivery increases dramatically as the number of sensors grows...
April 27, 2017: Sensors
https://www.readbyqxmd.com/read/28448448/in-vitro-ex-vivo-and-in-vivo-techniques-to-study-neuronal-migration-in-the-developing-cerebral-cortex
#17
REVIEW
Roberta Azzarelli, Roberto Oleari, Antonella Lettieri, Valentina Andre', Anna Cariboni
Neuronal migration is a fundamental biological process that underlies proper brain development and neuronal circuit formation. In the developing cerebral cortex, distinct neuronal populations, producing excitatory, inhibitory and modulatory neurotransmitters, are generated in different germinative areas and migrate along various routes to reach their final positions within the cortex. Different technical approaches and experimental models have been adopted to study the mechanisms regulating neuronal migration in the cortex...
April 27, 2017: Brain Sciences
https://www.readbyqxmd.com/read/28448434/static-memory-deduplication-for-performance-optimization-in-cloud-computing
#18
Gangyong Jia, Guangjie Han, Hao Wang, Xuan Yang
In a cloud computing environment, the number of virtual machines (VMs) on a single physical server and the number of applications running on each VM are continuously growing. This has led to an enormous increase in the demand of memory capacity and subsequent increase in the energy consumption in the cloud. Lack of enough memory has become a major bottleneck for scalability and performance of virtualization interfaces in cloud computing. To address this problem, memory deduplication techniques which reduce memory demand through page sharing are being adopted...
April 27, 2017: Sensors
https://www.readbyqxmd.com/read/28448316/regenerative-medicine-and-stem-cells-in-dermatology
#19
Eduardo K Moioli, Diana Bolotin, Murad Alam
BACKGROUND: Clinically relevant regenerative medicine is still in its early stages of development. Difficulties in regenerating large-scale and complex structures, the lack of safety data, and the paucity of clinical trials have slowed the process of technological advance. OBJECTIVE: To familiarize the clinician with techniques available in the laboratory and experimental approaches being tested clinically. In addition, a layout is discussed for how dermatologists can lead the way in bringing regenerative medicine to clinical reality...
April 12, 2017: Dermatologic Surgery: Official Publication for American Society for Dermatologic Surgery [et Al.]
https://www.readbyqxmd.com/read/28448310/comparison-of-power-versus-manual-injection-in-bolus-shape-and-image-quality-on-contrast-enhanced-magnetic-resonance-angiography-an-experimental-study-in-a-swine-model
#20
Takahiro Tsuboyama, Gregor Jost, Hubertus Pietsch, Noriyuki Tomiyama
OBJECTIVE: The aim of this study was to compare power versus manual injection in bolus shape and image quality on contrast-enhanced magnetic resonance angiography (CE-MRA). MATERIALS AND METHODS: Three types of CE-MRA (head-neck 3-dimensional [3D] MRA with a test-bolus technique, thoracic-abdominal 3D MRA with a bolus-tracking technique, and thoracic-abdominal time-resolved 4-dimensional [4D] MRA) were performed after power and manual injection of gadobutrol (0...
April 26, 2017: Investigative Radiology
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