491 research outputs found

    Satellite Radar Altimetry for Inland Hydrologic Studies

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    This research is conducted under the supervision of Dr. C.K. Shum, Professor of Geodetic Science, School of Earth Sciences, The Ohio State University. The research results documented in this report resulted in a PhD Dissertation. NASA and CNES provided the TOPEX/POSEIDON (Geophysical Data Record and Sensor Data Record, GDR and SDR) data products; LEGOS, USDA/NASA/GSFC provided high-level radar altimetry data products; ANA Brazil, and Environment Canada provided the stage gauge data used for this research. This research is supported by grants from NSF’s Hydrology Program (EAR-0440007) and NGA’s NURI Program (HM1582-07-1-2024), and the study was conducted with the objective to contribute to the Climate, Water, and Carbon Program at The Ohio State University.Satellite radar altimetry, which is originally designed to measure global ocean surface height, has been applied to inland surface water hydrologic studies. We have developed a water-detection algorithm based on statistical analysis of decadal TOPEX/POSEIDON height measurement time series, used the backscatter coefficient to classify the inland surface properties, and the 10-Hz (corresponding to an along track spatial resolution of 700m) radar waveform-retracked TOPEX data, to be able to observe small (<300Km2) inland bodies of water for hydrologic studies. We applied the algorithm to the selected study regions in Manitoba and northwestern (SW) Ontario, Canada, Amazon River Basin, and southwestern Taiwan. Finally we studied the application of TOPEX altimetry to the 1997 Red River flood monitoring. For the study regions in western Manitoba, the correlation coefficient between stage and TOPEX altimetry data in the large Lakes reaches 0.98 using the 10-Hz retracked data, thus verifying the validity and accuracy of the satellite measurement. The importance of the waveform retracking for the inland water applications is validated by the improvement of the correlation coefficients from 0.34 to 0.87 before and after retracking. We detected the bodies of water, which are otherwise missed by using the original 1-Hz data from the Geophysical Data Records, and illustrated that a higher spatial resolution could be achieved using the individual 10-Hz retracked data. In the Amazon River Basin, the capability of the water-detection algorithm is compared with the use of a high water level mask generated by SAR and other data with a spatial resolution of 100m. It is shown that the algorithm could detect the bodies of water, which are missed by the mask primarily because that the frequency of water fluctuation is more than twice a year at some locations. The bodies of water detected only by the algorithm are confirmed using the detailed local hydrological maps in 3 tested regions. The retrieved water height over the small (<300Km2) body of water was compared with the nearby stage measurement and showed good seasonal agreement. In the southwest Taiwan, the monthly variation of 10-Hz AGC from 1992 to 2002 were examined, it is found that the high AGC values could be used to indicate inundated area. We detected the annual and semi-annual variations from the 10-Hz AGC and 10-Hz retracked water height time series, which are attributable to two rainy seasons per year in the study region. For the study of the 1997 Red River flood, we compared the geographic distribution of 0 σ0 before, during and after the 1997 flood and found the high 0 σ0 values (>35dB) indicate the inundated regions. In addition, the comparison of the geographically distributed 0 σ0 during Winter, Spring, Summer and Autumn of 1997 showed that the low 0 σ values (<10dB) indicate snow coverage. The retrieved water height measurements in the flooded regions are compared with the nearby USGS stage measurements and showed good agreements. The comparison of 10-Hz individual retracked measurements with the 1-Hz nonretracked height measurements confirmed the importance of the retracked data (with higher spatial variations) in the flood monitoring. Using 0 σ0 and the retrieved water height measurements, we detected the 1997 flooded regions include the Red River Basin of the North in North Dakota and in western Minnesota, the upper Mississippi River Basin in Minnesota, the Missouri River Basin in southern North Dakota and in South Dakota. The observed flood extents from TOPEX agree well with and complement the USGS stage gauge records

    Satellite Radar Altimetry for Inland Hydrologic Studies

    Get PDF
    This research is conducted under the supervision of Dr. C.K. Shum, Professor of Geodetic Science, School of Earth Sciences, The Ohio State University. The research results documented in this report resulted in a PhD Dissertation. NASA and CNES provided the TOPEX/POSEIDON (Geophysical Data Record and Sensor Data Record, GDR and SDR) data products; LEGOS, USDA/NASA/GSFC provided high-level radar altimetry data products; ANA Brazil, and Environment Canada provided the stage gauge data used for this research. This research is supported by grants from NSF’s Hydrology Program (EAR-0440007) and NGA’s NURI Program (HM1582-07-1-2024), and the study was conducted with the objective to contribute to the Climate, Water, and Carbon Program at The Ohio State University.Satellite radar altimetry, which is originally designed to measure global ocean surface height, has been applied to inland surface water hydrologic studies. We have developed a water-detection algorithm based on statistical analysis of decadal TOPEX/POSEIDON height measurement time series, used the backscatter coefficient to classify the inland surface properties, and the 10-Hz (corresponding to an along track spatial resolution of 700m) radar waveform-retracked TOPEX data, to be able to observe small (<300Km2) inland bodies of water for hydrologic studies. We applied the algorithm to the selected study regions in Manitoba and northwestern (SW) Ontario, Canada, Amazon River Basin, and southwestern Taiwan. Finally we studied the application of TOPEX altimetry to the 1997 Red River flood monitoring. For the study regions in western Manitoba, the correlation coefficient between stage and TOPEX altimetry data in the large Lakes reaches 0.98 using the 10-Hz retracked data, thus verifying the validity and accuracy of the satellite measurement. The importance of the waveform retracking for the inland water applications is validated by the improvement of the correlation coefficients from 0.34 to 0.87 before and after retracking. We detected the bodies of water, which are otherwise missed by using the original 1-Hz data from the Geophysical Data Records, and illustrated that a higher spatial resolution could be achieved using the individual 10-Hz retracked data. In the Amazon River Basin, the capability of the water-detection algorithm is compared with the use of a high water level mask generated by SAR and other data with a spatial resolution of 100m. It is shown that the algorithm could detect the bodies of water, which are missed by the mask primarily because that the frequency of water fluctuation is more than twice a year at some locations. The bodies of water detected only by the algorithm are confirmed using the detailed local hydrological maps in 3 tested regions. The retrieved water height over the small (<300Km2) body of water was compared with the nearby stage measurement and showed good seasonal agreement. In the southwest Taiwan, the monthly variation of 10-Hz AGC from 1992 to 2002 were examined, it is found that the high AGC values could be used to indicate inundated area. We detected the annual and semi-annual variations from the 10-Hz AGC and 10-Hz retracked water height time series, which are attributable to two rainy seasons per year in the study region. For the study of the 1997 Red River flood, we compared the geographic distribution of 0 σ0 before, during and after the 1997 flood and found the high 0 σ0 values (>35dB) indicate the inundated regions. In addition, the comparison of the geographically distributed 0 σ0 during Winter, Spring, Summer and Autumn of 1997 showed that the low 0 σ values (<10dB) indicate snow coverage. The retrieved water height measurements in the flooded regions are compared with the nearby USGS stage measurements and showed good agreements. The comparison of 10-Hz individual retracked measurements with the 1-Hz nonretracked height measurements confirmed the importance of the retracked data (with higher spatial variations) in the flood monitoring. Using 0 σ0 and the retrieved water height measurements, we detected the 1997 flooded regions include the Red River Basin of the North in North Dakota and in western Minnesota, the upper Mississippi River Basin in Minnesota, the Missouri River Basin in southern North Dakota and in South Dakota. The observed flood extents from TOPEX agree well with and complement the USGS stage gauge records

    Effects of 1-methylcyclopropene on superficial scald and related metabolism in ‘Wujiuxiang’ pears during cold storage

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    ‘Wujiuxiang’ (Pyrus bretschneideri R. × Pyrus communis L.) pears often suffer from superficial scald after long-term cold storage. In this study, harvested ‘Wujiuxiang’ pear fruits were fumigated with 1-MCP at concentrations of 0.5 μL/L and 1.0 μL/L and subsequently stored at low temperature (0 °C). The superficial scald index; flesh firmness; total soluble solids (TSS) content; respiration and ethylene production rates; relative membrane permeability; concentrations of α-farnesene, conjugated trienols (CTols), and hydrogen peroxide (H2O2); and activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and lipoxygenase (LOX) of the peel were investigated. The results showed that compared with control, 1-MCP reduced the index of superficial scald; maintained a higher firmness and a lower TSS content; inhibited the accumulation of H2O2, α-farnesene and conjugated trienols and the increase in cell membrane permeability; and maintained a higher activity of APX, SOD and CAT and a lower activity of LOX. These findings indicate that 1-MCP regulates the activities of H2O2-scavenging enzymes to inhibit the accumulation of H2O2 and thereby reduces cell membrane damage and inhibits the accumulation of conjugated trienols. Thus, 1-MCP could decrease the incidence of superficial scald in ‘Wujiuxiang’ pears

    The effects of three different grinding methods in DNA extraction of cowpea (Vigna unguiculata L. Walp)

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    Rapid DNA extraction is a prerequisite for molecular studies. Generally, plant tissue is ground in liquid nitrogen to isolate DNA; but, liquid nitrogen is dangerous and volatile. Besides, liquid nitrogen is not always available in many developing countries. To investigate if high quality DNA could be obtained for downstream PCR analysis without liquid nitrogen, the cowpea DNA was extracted by Hexadecyl trimethyl ammonium bromide cetyl trimethylammonium bromide (CTAB) method and sodium dodecyl sulphate (SDS) method, respectively, each with three different grinding methods, including ground in liquid nitrogen, in preheated mortar and in non-preheated mortar. The DNA was compared according to their yield, purity, integrity and functionality. The results showed that high quality DNA could be obtained by three grinding methods both in CTAB method and SDS method. Without liquid nitrogen, grinding plant tissue in preheated or non-preheated mortar with extraction buffer to extract DNA is feasible.Keywords: Cowpea (Vigna unguiculata), grinding method, liquid nitrogen, DNA extractionAfrican Journal of Biotechnology Vol. 12(16), pp. 1946-195

    Study on Motivations and Cultivation of Cultural Industry Cluster in Jilin Province, China

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    Abstract Cultural industry is honored as one of the industries in the 21 st Century that has the greatest development prospect. With its innovativeness, competitiveness and value added, it has become the leading edge and high end among the emerging industries in the current world, and it has also become one of the characteristic industries that have the greatest development potential in transferring the economic growth mode, promoting swift and coordinated development of regional economy in the old industrial bases. Cultural industry is playing a more and more important role in development of regional economy. Cluster is an important feature of cultural industry and cluster development is an inexorable trend in development of cultural industry. Cultural industry in Jilin Province in recent years has been rapidly developed. Nevertheless, there still exist quite a lot of problems and drawbacks. Thus, Jilin Province should find out its own characteristic factors according to its local cultural characteristics and start out from improving cultural industry policy, constructing a cultural industry cluster pattern that has comparative advantages and local features, cultivating leading key cultural enterprises and balancing cultural industrial development of all cities so as to diminish gap between different areas and improving talent security system, do a good job in taking the path of cultural industry cluster development and form cluster scale effect

    The influence of foveal lexical processing load on parafoveal preview and saccadic targeting during Chinese reading

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    Whether increased foveal load causes a reduction of parafoveal processing remains equivocal. The present study examined foveal load effects on parafoveal processing in natural Chinese reading. Parafoveal preview of a single-character parafoveal target word was manipulated by using the boundary paradigm (Rayner, 1975; pseudocharacter or identity previews) under high foveal load (low-frequency pretarget word) compared with low foveal load (high-frequency pretarget word) conditions. Despite an effective manipulation of foveal processing load, we obtained no evidence of any modulatory influence on parafoveal processing in first-pass reading times. However, our results clearly showed that saccadic targeting, in relation to forward saccade length from the pretarget word and in relation to target word skipping, was influenced by foveal load and this influence occurred independent of parafoveal preview. Given the optimal experimental conditions, these results provide very strong evidence that preview benefit is not modulated by foveal lexical load during Chinese reading. (PsycINFO Database Record (c) 2019 APA, all rights reserved

    A Biodegradable Polyethylenimine-Based Vector Modified by Trifunctional Peptide R18 for Enhancing Gene Transfection Efficiency In Vivo

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    Lack of capacity to cross the nucleus membrane seems to be one of the main reasons for the lower transfection efficiency of gene vectors observed in vivo study than in vitro. To solve this problem, a new non-viral gene vector was designed. First, a degradable polyethylenimine (PEI) derivate was synthesized by crosslinking low-molecular-weight (LMW) PEI with N-octyl-N-quaternary chitosan (OTMCS), and then adopting a designed trifunctional peptide (RGDC- TAT-NLS) with good tumor targeting, cell uptake and nucleus transport capabilities to modify OTMCS-PEI. The new gene vector was termed as OTMCS- PEI-R18 and characterized in terms of its chemical structure and biophysical parameters. Gene transfection efficiency and nucleus transport mechanism of this vector were also evaluated. The polymer showed controlled degradation and remarkable buffer capabilities with the particle size around 100–300 nm and the zeta potential ranged from 5 mV to 40 mV. Agraose gel electrophoresis showed that OTMCS-PEI-R18 could effectively condensed plasmid DNA at a ratio of 1.0. Besides, the polymer was stable in the presence of sodium heparin and could resist digestion by DNase I at a concentration of 63U DNase I/DNA. OTMCS-PEI-R18 also showed much lower cytotoxicity and better transfection rates compared to polymers OTMCS-PEI-R13, OTMCS-PEI and PEI 25 KDa in vitro and in vivo. Furthermore, OTMCS-PEI-R18/DNA complexes could accumulate in the nucleus well soon and not rely on mitosis absolutely due to the newly incorporated ligand peptide NLS with the specific nuclear delivery pathway indicating that the gene delivery system OTMCS-PEI-R18 could reinforce gene transfection efficiency in vivo

    Parafoveal Previews and Lexical Frequency in Natural Reading: Evidence from Eye Movements and Fixation-Related Potentials

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    Participants’ eye movements and EEG signal were recorded as they read sentences displayed according to the gaze-contingent boundary paradigm. Two target words in each sentence were manipulated for lexical frequency (high vs. low frequency) and parafoveal preview of each target word (identical vs. string of random letters vs. string of Xs). Eye movement data revealed visual parafoveal-on-foveal effects (POF), as well as foveal visual and orthographic preview effects and word frequency effects. Fixation-related potentials (FRPs) showed visual and orthographic PoF effects as well as foveal visual and orthographic preview effects. Our results replicated the early preview positivity effect (Dimigen et al., 2012) in the X-string preview condition, and revealed different neural correlates associated with a preview comprised of a string of random letters relative to a string of Xs. The former effects seem likely to reflect difficulty associated with the integration of parafoveal and foveal information, as well as feature overlap, while the latter reflect inhibition, and potentially disruption, to processing underlying reading. Interestingly, and consistent with Kretzschmar, Schlesewsky and Staub (2015), no frequency effect was reflected in the FRP measures. The findings provide insight into the neural correlates of parafoveal processing and written word recognition in reading and demonstrate the value of utilising ecologically valid paradigms to study well established phenomena that occur as text is read naturally

    Efficient detoxication of hydroxylamine and nitrite through heterotrophic nitrification and aerobic denitrification by Acinetobacter johnsonii EN-J1

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    The co-existence of hydroxylamine (NH2OH) and nitrite (NO2–-N) can aggravate the difficulty of wastewater treatment. The roles of hydroxylamine (NH2OH) and nitrite (NO2–-N) in accelerating the elimination of multiple nitrogen sources by a novel isolated strain of Acinetobacter johnsonii EN-J1 were investigated in this study. The results demonstrated that strain EN-J1 could eliminate 100.00% of NH2OH (22.73 mg/L) and 90.09% of NO2–-N (55.32 mg/L), with maximum consumption rates of 1.22 and 6.75 mg/L/h, respectively. Prominently, the toxic substances NH2OH and NO2–-N could both facilitate nitrogen removal rates. Compared with the control treatment, the elimination rates of nitrate (NO3–-N) and NO2–-N were enhanced by 3.44 and 2.36 mg/L/h after supplementation with 10.00 mg/L NH2OH, and those of ammonium (NH4+-N) and NO3–-N were improved by 0.65 and 1.00 mg/L/h after the addition of 50.00 mg/L NO2–-N. Furthermore, the nitrogen balance results indicated that over 55.00% of the initial total nitrogen was transformed into gaseous nitrogen by heterotrophic nitrification and aerobic denitrification (HN-AD). Ammonia monooxygenase (AMO), hydroxylamine oxidoreductase (HAO), nitrate reductase (NR), and nitrite reductase (NIR), which are essential for HN-AD, were detected at levels of 0.54, 0.15, 0.14, and 0.01 U/mg protein, respectively. All findings confirmed that strain EN-J1 could efficiently execute HN-AD, detoxify NH2OH and NO2–-N, and ultimately promote nitrogen removal rates
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