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https://www.readbyqxmd.com/read/27906381/video-stabilization-in-atmosphere-turbulent-conditions-based-on-the-laplacian-riesz-pyramid
#1
Bindang Xue, Yi Liu, Linyan Cui, Xiangzhi Bai, Xiaoguang Cao, Fugen Zhou
Video stabilization in atmosphere turbulent conditions is aimed at removing spatiotemporally varying distortions from video recordings. Conventional shaky video stabilization approaches do not perform effectively under turbulent circumstances due to the erratic motion common to those conditions. Using complex-valued image pyramids, we propose a method to mitigate this erratic motion in videos. First, each frame of a video is decomposed into different spatial frequencies using the Laplacian pyramid. Second, a Riesz transform is adopted to extract the local amplitude and the local phase of each sub-band...
November 28, 2016: Optics Express
https://www.readbyqxmd.com/read/27906335/multiple-spatial-modes-based-qkd-over-marine-free-space-optical-channels-in-the-presence-of-atmospheric-turbulence
#2
Xiaole Sun, Ivan B Djordjevic, Mark A Neifeld
We investigate a multiple spatial modes based quantum key distribution (QKD) scheme that employs multiple independent parallel beams through a marine free-space optical channel over open ocean. This approach provides the potential to increase secret key rate (SKR) linearly with the number of channels. To improve the SKR performance, we describe a back-propagation mode (BPM) method to mitigate the atmospheric turbulence effects. Our simulation results indicate that the secret key rate can be improved significantly by employing the proposed BPM-based multi-channel QKD scheme...
November 28, 2016: Optics Express
https://www.readbyqxmd.com/read/27906254/propagation-of-the-oam-mode-carried-by-partially-coherent-modified-bessel-gaussian-beams-in-an-anisotropic-non-kolmogorov-marine-atmosphere
#3
Yun Zhu, Minyu Chen, Yixin Zhang, Ye Li
This study investigates the effect of the anisotropic non-Kolmogorov turbulence of the marine atmosphere on propagation of orbital angular momentum (OAM) modes carried by partially coherent modified Bessel-Gaussian (PCMBG) beams. The analytic formula of the probability density of OAM modes is derived and used to explore the evolution of the received power of the OAM mode. PCMBG beams with long wavelength, low quantum number of the OAM mode, and a high spectral degree of coherence of the source are robust for the OAM mode propagation in turbulence...
December 1, 2016: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/27905827/modeling-pn2-through-geological-time-implications-for-planetary-climates-and-atmospheric-biosignatures
#4
E E Stüeken, M A Kipp, M C Koehler, E W Schwieterman, B Johnson, R Buick
Nitrogen is a major nutrient for all life on Earth and could plausibly play a similar role in extraterrestrial biospheres. The major reservoir of nitrogen at Earth's surface is atmospheric N2, but recent studies have proposed that the size of this reservoir may have fluctuated significantly over the course of Earth's history with particularly low levels in the Neoarchean-presumably as a result of biological activity. We used a biogeochemical box model to test which conditions are necessary to cause large swings in atmospheric N2 pressure...
December 1, 2016: Astrobiology
https://www.readbyqxmd.com/read/27905609/pursuing-reliable-thermal-analysis-techniques-for-energetic-materials-decomposition-kinetics-and-thermal-stability-of-dihydroxylammonium-5-5-bistetrazole-1-1-diolate-tkx-50
#5
Nikita V Muravyev, Konstantin A Monogarov, Andrey F Asachenko, Mikhail S Nechaev, Ivan V Ananyev, Igor V Fomenkov, Vitaly G Kiselev, Alla N Pivkina
Thermal decomposition of a novel promising high-performance explosive dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) was studied using a number of thermal analysis techniques (thermogravimetry, differential scanning calorimetry, and accelerating rate calorimetry, ARC). To obtain more comprehensive insight into the kinetics and mechanism of TKX-50 decomposition, a variety of complementary thermoanalytical experiments were performed under various conditions. Non-isothermal and isothermal kinetics were obtained at both atmospheric and low (up to 0...
December 1, 2016: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/27905552/protonation-enhancement-by-dichloromethane-doping-in-low-pressure-photoionization
#6
Jinian Shu, Yao Zou, Ce Xu, Zhen Li, Wanqi Sun, Bo Yang, Haixu Zhang, Peng Zhang, Pengkun Ma
Doping has been used to enhance the ionization efficiency of analytes in atmospheric pressure photoionization, which is based on charge exchange. Compounds with excellent ionization efficiencies are usually chosen as dopants. In this paper, we report a new phenomenon observed in low-pressure photoionization: Protonation enhancement by dichloromethane (CH2Cl2) doping. CH2Cl2 is not a common dopant due to its high ionization energy (11.33 eV). The low-pressure photoionization source was built using a krypton VUV lamp that emits photons with energies of 10...
December 1, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27905442/quantifying-global-soil-carbon-losses-in-response-to-warming
#7
T W Crowther, K E O Todd-Brown, C W Rowe, W R Wieder, J C Carey, M B Machmuller, B L Snoek, S Fang, G Zhou, S D Allison, J M Blair, S D Bridgham, A J Burton, Y Carrillo, P B Reich, J S Clark, A T Classen, F A Dijkstra, B Elberling, B A Emmett, M Estiarte, S D Frey, J Guo, J Harte, L Jiang, B R Johnson, G Kröel-Dulay, K S Larsen, H Laudon, J M Lavallee, Y Luo, M Lupascu, L N Ma, S Marhan, A Michelsen, J Mohan, S Niu, E Pendall, J Peñuelas, L Pfeifer-Meister, C Poll, S Reinsch, L L Reynolds, I K Schmidt, S Sistla, N W Sokol, P H Templer, K K Treseder, J M Welker, M A Bradford
The majority of the Earth's terrestrial carbon is stored in the soil. If anthropogenic warming stimulates the loss of this carbon to the atmosphere, it could drive further planetary warming. Despite evidence that warming enhances carbon fluxes to and from the soil, the net global balance between these responses remains uncertain. Here we present a comprehensive analysis of warming-induced changes in soil carbon stocks by assembling data from 49 field experiments located across North America, Europe and Asia...
November 30, 2016: Nature
https://www.readbyqxmd.com/read/27905399/cellular-reactions-to-long-term-volatile-organic-compound-voc-exposures
#8
Johanna M Gostner, Johannes Zeisler, Mohammad Tauqeer Alam, Peter Gruber, Dietmar Fuchs, Kathrin Becker, Kerstin Neubert, Markus Kleinhappl, Stefan Martini, Florian Überall
Investigations of cellular processes initiated by volatile organic compounds (VOCs) are limited when modelling realistic long-term exposure scenarios at low concentrations. Exposure to indoor VOCs is associated with a range of adverse effects, but data on molecular changes at regulatory threshold limits are lacking. Activity analysis of VOC in vitro can be a valuable complement to inhalation toxicological evaluations. We developed an exposure platform that generates a stable VOC atmosphere and allows the exposure of cells for longer periods...
December 1, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27903654/carbon-and-acyl-chain-flux-during-stress-induced-triglyceride-accumulation-by-stable-isotopic-labeling-of-the-polar-microalga-coccomyxa-subellipsoidea-c169
#9
James W Allen, Concetta C DiRusso, Paul N Black
Deriving biofuels and other lipoid products from algae is a promising future technology directly addressing global issues of atmospheric CO2 balance. To better understand the metabolism of triglyceride synthesis in algae, we examined their metabolic origins in the model species, Coccomyxa subellipsoidea C169, using stable isotopic labeling. Labeling patterns arising from (13)C-U-glucose, (13)CO2, or D2O supplementation were analyzed by GC-MS and/or LC-MS over time courses during nitrogen (N) starvation to address the roles of catabolic carbon (C) recycling, acyl chain redistribution, and de novo fatty acid (FA) synthesis during the expansion of the lipid bodies...
November 30, 2016: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/27902861/thioaldehydes-from-aldehyde-hydrogen-sulfide-interaction-under-organocatalysis
#10
Joseph S Francisco, Manoj Kumar
Thioaldehydes are an important class of sulfur compounds involved in atmospheric, synthetic organic and biological chemistry. Traditionally, they are believed to be formed by the nucleophilic attack of bisulfide anion on the carbonyl compounds. Herein we suggest a novel mechanism that does not require the formation of bisulfide anion, but rather involves an interaction between hydrogen sulfide and an aldehyde. Though the uncatalyzed or the water-catalyzed reactions involve high barriers, the formic acid-catalyzed reactions involve moderate barriers that should be accessible in planetary atmospheres...
November 30, 2016: Chemistry: a European Journal
https://www.readbyqxmd.com/read/27902716/large-scale-anthropogenic-reduction-of-forest-cover-in-last-glacial-maximum-europe
#11
Jed O Kaplan, Mirjam Pfeiffer, Jan C A Kolen, Basil A S Davis
Reconstructions of the vegetation of Europe during the Last Glacial Maximum (LGM) are an enigma. Pollen-based analyses have suggested that Europe was largely covered by steppe and tundra, and forests persisted only in small refugia. Climate-vegetation model simulations on the other hand have consistently suggested that broad areas of Europe would have been suitable for forest, even in the depths of the last glaciation. Here we reconcile models with data by demonstrating that the highly mobile groups of hunter-gatherers that inhabited Europe at the LGM could have substantially reduced forest cover through the ignition of wildfires...
2016: PloS One
https://www.readbyqxmd.com/read/27902294/actinocrinis-puniceicyclus-gen-nov-sp-nov-a-novel-actinobacterium-isolated-from-an-acidic-spring-in-kootenay-national-park-canada
#12
Joong-Jae Kim, Colbran E Marjerrison, Sabrina L Cornish Shartau, Allyson L Brady, Christine E Sharp, W Irene C Rijpstra, Jaap S Sinninghe Damsté, Peter Schumann, Stephen E Grasby, Peter F Dunfield
An aerobic, mildly acidophilic actinobacterium was isolated from the Ochre Beds bog in Kootenay National Park, Canada. Cells of isolate OB1T were Gram-positive, non-motile, pink-to purple-pigmented filaments. The pH range for growth was 3.5 - 6.5 (optimum 5.5), and the temperature range was 13-37 oC. The major cellular fatty acids were 16:0 iso (28.5 %), 15:0 iso (14.6 %) and 15:0 anteiso (14.3 %), and the major polar lipid was phosphohexose. The major quinone was menaquinone-11 (MK-11) and the peptidoglycan type was A1γ...
November 16, 2016: International Journal of Systematic and Evolutionary Microbiology
https://www.readbyqxmd.com/read/27902262/saccharedens-versatilis-gen-nov-sp-nov-a-sugar-degrading-member-of-the-burkholderiales-isolated-from-cephalotes-rohweri-ant-guts
#13
Jonathan Y Lin, William J Hobson, John T Wertz
Cephalotes "turtle" ants host a core group of gut-associated symbionts, but their potential contributions to ant nutrition and disease resistance remain uncharacterized in vitro. To gain a better understanding of the metabolic capability of core symbionts belonging to the Burkholderiales, we cultivated and characterized strain CAG32T, isolated from the guts of Cephalotes rohweri ants. Strain CAG32T was rod-shaped, Gram-negative, motile, and formed pale-white colonies on trypticase soy agar. Optimum growth occurred under an atmosphere of 20% O2 supplemented with 1% CO2...
November 9, 2016: International Journal of Systematic and Evolutionary Microbiology
https://www.readbyqxmd.com/read/27901306/plants-microorganisms-and-soil-temperatures-contribute-to-a-decrease-in-methane-fluxes-on-a-drained-arctic-floodplain
#14
Min Jung Kwon, Felix Beulig, Iulia Ilie, Marcus Wildner, Kirsten Küsel, Lutz Merbold, Miguel D Mahecha, Nikita Zimov, Sergey A Zimov, Martin Heimann, Edward A G Schuur, Joel E Kostka, Olaf Kolle, Ines Hilke, Mathias Göckede
As surface temperatures are expected to rise in the future, ice-rich permafrost may thaw, altering soil topography and hydrology and creating a mosaic of wet and dry soil surfaces in the Arctic. Arctic wetlands are large sources of CH4 , and investigating effects of soil hydrology on CH4 fluxes is of great importance for predicting ecosystem feedback in response to climate change. In this study, we investigate how a decade-long drying manipulation on an Arctic floodplain influences CH4 -associated microorganisms, soil thermal regimes, and plant communities...
November 7, 2016: Global Change Biology
https://www.readbyqxmd.com/read/27900861/thermal-desorption-combined-with-atmospheric-pressure-photo-ionization-for-the-analysis-of-volatile-compounds-and-its-possible-applications
#15
Yury Kostyukevich, Ludmila Borisova, Alexey Kononikhin, Igor Popov, Eugene Kukaev, Eugene Nikolaev
We report an approach to study volatile organic compounds based on thermal desorption combined with atmospheric pressure photo ionization. The approach allows the sequential evaporation of different fractions of the sample, which simplifies the mass spectrum. We have applied the developed method for the detection of petroleum in vegetable oil. We have shown that in the negative mode, ions of fatty acids corresponding to vegetable oil dominates, while in the positive mode under relatively low temperature the light fraction of petroleum rapidly evaporates making it easy detectable...
2016: European Journal of Mass Spectrometry
https://www.readbyqxmd.com/read/27900860/atmospheric-pressure-thermal-ionization-ion-source-for-peptide-analysis
#16
Eugenii N Kukaev, Alexey S Kononikhin, Natalia L Starodubtseva, Yury I Kostyukevich, Igor A Popova, Vitaliy Chagovets, Konstantin O Nagornov, Eugene N Nikolaev
A novel atmospheric pressure thermal ionization (APTI) ion source was developed for the analysis of liquid samples. The feasibility of the ion source was demonstrated on peptides using two configurations-assisted by hot wire or hot surface. Microalloyed molybdenum, used as a thermal ion- emitter, notably facilitated the formation of multiply-charged ions, but fragmentation products were still observed. Peptide fragmentation accompanying thermal ionization can be used for peptide identification. The described method is promising for studies of biological samples with minimal pre-treatment...
2016: European Journal of Mass Spectrometry
https://www.readbyqxmd.com/read/27900858/rapid-identification-of-triphenylmethane-dyes-by-ion-mobility-time-of-flight-mass-spectrometry
#17
Alexey A Sysoev, Sergey S Poteshin, Denis M Chernyshev, Alexander A Sysoev
An ion mobility time-of-flight mass spectrometry (IM-TOFMS)-based method has been preliminarily investigated for the identification of triphenylmethane ballpoint pen dyes on paper. The dyes were sampled from one-year-old ballpoint pen ink entries. The entries were written on paper documents stored in the dark in a bookcase. Sample solutions were prepared by extraction of dyes in a vial. Basic violet 2, Methyl violet 6B, Methyl violet 2B and Crystal violet were characterized by IM-TOFMS. Since the ballpoint ink dyes contain ionic compounds, the studied compounds were expected to form stable peaks in the atmospheric pressure drift tube ion mobility spectrometry, and this was experimentally verified...
2016: European Journal of Mass Spectrometry
https://www.readbyqxmd.com/read/27900722/atmospheric-deposition-of-pbdes-and-dps-in-dongjiang-river-basin-south-china
#18
Xiaowei Wu, Yan Wang, Minmin Hou, Chunling Luo, Hongxia Zhao, Gan Zhang
The atmospheric deposition fluxes of polybrominated diphenyl ethers (PBDEs) and Dechlorane Plus (DPs) in Dongjiang River Basin of the Pearl River Delta in South China were investigated during winter and summer, respectively. The total deposition fluxes varied from 4.74 to 27.0 ng/m(2)/day for PBDEs and 8.77 to 206 ng/m(2)/day for DPs, respectively. The fractions of anti-DP to the total DPs (f anti) varied from 0.28 to 0.63 (mean = 0.43 ± 0.06), i.e., generally lower than those in commercial products, which might be attributed to the different environmental fates of the two isomers...
November 30, 2016: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/27900624/the-sources-of-trace-element-pollution-of-dry-depositions-nearby-a-drinking-water-source
#19
Xinyue Guo, Hongbing Ji, Cai Li, Yang Gao, Huaijian Ding, Lei Tang, Jinguo Feng
Miyun Reservoir is one of the most important drinking water sources for Beijing. Thirteen atmospheric PM sampling sites were established around this reservoir to analyze the mineral composition, morphological characteristics, element concentration, and sources of atmospheric PM pollution, using transmission electron microscope, X-ray diffraction, and inductively coupled plasma mass spectrometry analyses. The average monthly dry deposition flux of aerosols was 15.18 g/m(2), with a range of 5.78-47.56 g/m(2)...
November 29, 2016: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/27900419/measurement-of-giardia-lamblia-adhesion-force-using-an-integrated-microfluidic-assay
#20
Ling Lu, Guo-Xia Zheng, Yu-Suo Yang, Cheng-Yu Feng, Fang-Fang Liu, Yun-Hua Wang
The mechanisms how Giardias attach to the intestinal epithelium remain unclear. None of the methods currently being used to measure the attachment force could provide a continuous nutrition supply and a micro-aerobic atmosphere to the Giardia. Besides, they are all labor-intensive. In the present research, a microfluidic method based on electric circuit analogy was developed. The input fluid flowed through the inlet channel with different lengths and was distributed in four assay chambers. Shear force gradients were generated in chambers, too...
November 30, 2016: Analytical and Bioanalytical Chemistry
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