WorldWideScience

Sample records for oxidants potentiate yield

  1. Improving carbon dioxide yields and cell efficiencies for ethanol oxidation by potential scanning

    Science.gov (United States)

    Majidi, Pasha; Pickup, Peter G.

    2014-12-01

    An ethanol electrolysis cell with aqueous ethanol supplied to the anode and nitrogen at the cathode has been operated under potential cycling conditions in order to increase the yield of carbon dioxide and thereby increase cell efficiency relative to operation at a fixed potential. At ambient temperature, faradaic yields of CO2 as high as 26% have been achieved, while only transient CO2 production was observed at constant potential. Yields increased substantially at higher temperatures, with maximum values at Pt anodes reaching 45% at constant potential and 65% under potential cycling conditions. Use of a PtRu anode increased the cell efficiency by decreasing the anode potential, but this was offset by decreased CO2 yields. Nonetheless, cycling increased the efficiency relative to constant potential. The maximum yields at PtRu and 80 °C were 13% at constant potential and 32% under potential cycling. The increased yields under cycling conditions have been attributed to periodic oxidative stripping of adsorbed CO, which occurs at lower potentials on PtRu than on Pt. These results will be important in the optimization of operating conditions for direct ethanol fuel cells and for the electrolysis of ethanol to produce clean hydrogen.

  2. Potential nitrous oxide yield of AOA vs. AOB and utilization of carbon and nitrogen in the ammonia oxidizing process in the Pearl River Estuary

    Science.gov (United States)

    Ma, L.; Dai, M.; Tan, S.; Xia, X.; Liu, H.

    2016-12-01

    Nitrous oxide (N2O), a greenhouse gas, is a by-product during ammonia oxidation process, the production of which is often stimulated under low dissolved oxygen (DO) in the estuarine environment. The potential yield of N2O has been considered to be driven by ammonia-oxidizing bacteria (AOB) of Betaproteobacteria & Gammaproteobacteria and/or ammonia-oxidizing archaea (AOA) of Thaumarchaeota. In order to examine the relative importance of AOA and AOB in producing N2O and in modulating the potential N2O yield, arch-amoA, beta-amoA, gamma-amoA encoding for the alpha subunit of the ammonia monooxygenase (AMO) are used as biomarkers to identify the distributions and bioactivities of AOA and AOB in the Pearl River Estuary (PRE). Size fractionation experiments were conducted to distinguish AOA and AOB on particles in different size-fractions of > 3 μm, 0.45-3 μm, and 0.22-0.45 μm. Pure culture of N. maritimusSCM1 was studied as a model organism to identify the organic carbon production during ammonia oxidation by SCM1 strains. Our results show that AOA distributes largely in the free-living state and could adapt to very limited ammonia substrate and low saturation of DO; AOB mainly distributes at the particle-attached state under relative richer ammonia and high DO conditions; however, the RNA/DNA ratio of AOB was higher than that of AOA under the same conditions suggesting AOB is relatively more actively expressed. In the upper reach of PRE, the dominant microorganism in the water column was AOB and the in situ N2O/NH3 therein ranged 0.73-3.74 ‰. In the lower PRE, AOA was dominated, and the in situ N2O/NH3 was of 1.17- 7.32‰. At selected sites, we estimated isotope effect (e) of AOA (eDIC/bulk) as -23.94‰ and AOB (eDIC/bulk) as -56.6‰ to -44.8‰, which is consistent with the studies of pure cultures. The coefficient of C sequestration "k", defined as (C biomass / DIC in situ) / (N biomass / ammonia in situ) to differ the utilization of carbon and nitrogen, of

  3. Potential oil yield, fatty acid composition, and oxidation stability of the hempseed oil from four Cannabis sativa L. cultivars.

    Science.gov (United States)

    Da Porto, Carla; Decorti, Deborah; Natolino, Andrea

    2015-03-01

    The cultivation of four industrial hemp cultivars (Felina 32, Chamaeleon, Uso31, and Finola) was investigated for oil production in the north-east of Italy along two years. The oils of all cultivars resulted in rich amount of linoleic acid (ω-6) and α-linolenic acid (ω-3). Felina 32 and Chamaeleon oils exhibited the highest amount of linoleic acid (59%) and α-linolenic acid (18%). Finola and Uso31 oils resulted in the richest of γ-linolenic acid (5-6%). All hempseed oils presented high oxidation stability and an acceptable initial quality. It is suggested that these oils can be used to produce EFA dietary supplements high in ω-6 and ω-3 of vegetal origin.

  4. Assessing potential sustainable wood yield

    Science.gov (United States)

    Robert F. Powers

    2001-01-01

    Society is making unprecedented demands on world forests to produce and sustain many values. Chief among them is wood supply, and concerns are rising globally about the ability of forests to meet increasing needs. Assessing this is not easy. It requires a basic understanding of the principles governing forest productivity: how wood yield varies with tree and stand...

  5. Yield Potential of Hemp (Cannabis sativa L.) Cultivars in Denmark

    DEFF Research Database (Denmark)

    Deleuran, Lise Christina; Flengmark, Poul Kristiansen

    2005-01-01

    In order to determine the yield potential of fibre hemp in Denmark, defined as seed yield, biomass, stem and fibre production, five cultivars were evaluated in field trials at two sites during 1998-2000. The total dry matter yield, stem yield, fibre yield, fibre percent, plant height, and seed...

  6. Oxygen potentials of transuranium oxides

    International Nuclear Information System (INIS)

    Haruyoshi Otobe; Mituso Akabori; Arai Yasuo; Kazuo Minato

    2008-01-01

    The oxygen potentials of pyrochlore-type Pu 2 Zr 2 O 7+y , fluorite-type (Pu 0.5 Zr 0.5 )O 2-x and AmO 2-x have been measured by the electromotive force (EMF) method with a zirconia solid-electrolyte. The oxygen potentials of these oxides were reviewed. The phase relations, microstructure, equilibrium state of these oxides were discussed, referring to the isothermal curve of the oxygen potentials. (authors)

  7. Simulating potential growth and yield of oil palm with PALMSIM

    NARCIS (Netherlands)

    Hoffmann, M.P.; Vera, A.C.; Wijk, van M.T.; Giller, K.E.; Oberthur, R.; Donough, C.; Whitbread, A.M.; Fisher, M.J.

    2014-01-01

    The growing demand for palm oil can be met by reducing the gap between potential yield and actual yield. Simulation models can quantify potential yield, and therefore indicate the scope for intensification. A relatively simple physiological approach was used to develop PALMSIM, which is a model that

  8. Effect of Oxidation Time on Humic Acid Yields

    International Nuclear Information System (INIS)

    Khin Thidar Cho; May Zin Lwin

    2010-12-01

    In this study,humic acids were produced from coal under controlled conditions by using different oxidation time. This research studies on the behaviour of coal during oxidation process. The coal used as raw material in this research was obtained from Ka Lay Wa, Sagaing Division . The coals were oxidized at the different oxidation times from 76 hr to 380 hr at the temperature 150 5C. The yields of humic acid, the ultimate analysis (percentage of carbon, hydrogen, nitrogen and oxygen) and the proximate analysis (percentage of volatile, ash and moisture) were done in this study. The functional groups and structural entities of the obtained humic acids were identified by using Fourier Transform Infrared Spectrophotometer (FTIR). The yield percentage of prepared humic acid in Ka Lay Wa coal was found to be 3%.

  9. Optimizing rice yields while minimizing yield-scaled global warming potential.

    Science.gov (United States)

    Pittelkow, Cameron M; Adviento-Borbe, Maria A; van Kessel, Chris; Hill, James E; Linquist, Bruce A

    2014-05-01

    To meet growing global food demand with limited land and reduced environmental impact, agricultural greenhouse gas (GHG) emissions are increasingly evaluated with respect to crop productivity, i.e., on a yield-scaled as opposed to area basis. Here, we compiled available field data on CH4 and N2 O emissions from rice production systems to test the hypothesis that in response to fertilizer nitrogen (N) addition, yield-scaled global warming potential (GWP) will be minimized at N rates that maximize yields. Within each study, yield N surplus was calculated to estimate deficit or excess N application rates with respect to the optimal N rate (defined as the N rate at which maximum yield was achieved). Relationships between yield N surplus and GHG emissions were assessed using linear and nonlinear mixed-effects models. Results indicate that yields increased in response to increasing N surplus when moving from deficit to optimal N rates. At N rates contributing to a yield N surplus, N2 O and yield-scaled N2 O emissions increased exponentially. In contrast, CH4 emissions were not impacted by N inputs. Accordingly, yield-scaled CH4 emissions decreased with N addition. Overall, yield-scaled GWP was minimized at optimal N rates, decreasing by 21% compared to treatments without N addition. These results are unique compared to aerobic cropping systems in which N2 O emissions are the primary contributor to GWP, meaning yield-scaled GWP may not necessarily decrease for aerobic crops when yields are optimized by N fertilizer addition. Balancing gains in agricultural productivity with climate change concerns, this work supports the concept that high rice yields can be achieved with minimal yield-scaled GWP through optimal N application rates. Moreover, additional improvements in N use efficiency may further reduce yield-scaled GWP, thereby strengthening the economic and environmental sustainability of rice systems. © 2013 John Wiley & Sons Ltd.

  10. Distribution of genes associated with yield potential and water ...

    Indian Academy of Sciences (India)

    Supplementary data: Distribution of genes associated with yield potential and water-saving in. Chinese Zone II wheat detected by developed functional markers. Zhenxian Gao, Zhanliang Shi, Aimin Zhang and Jinkao Guo. J. Genet. 94, 35–42. Table 1. Functional markers for high-yield or water-saving genes in wheat and ...

  11. Quantifying potential yield and water-limited yield of summer maize in the North China Plain

    Science.gov (United States)

    Jiang, Mingnuo; Liu, Chaoshun; Chen, Maosi

    2017-09-01

    The North China Plain is a major food producing region in China, and climate change could pose a threat to food production in the region. Based on China Meteorological Forcing Dataset, simulating the growth of summer maize in North China Plain from 1979 to 2015 with the regional implementation of crop growth model WOFOST. The results showed that the model can reflect the potential yield and water-limited yield of Summer Maize in North China Plain through the calibration and validation of WOFOST model. After the regional implementation of model, combined with the reanalysis data, the model can better reproduce the regional history of summer maize yield in the North China Plain. The yield gap in Southeastern Beijing, southern Tianjin, southern Hebei province, Northwestern Shandong province is significant, these means the water condition is the main factor to summer maize yield in these regions.

  12. Economics and yields of energy plantations: Status and potential

    International Nuclear Information System (INIS)

    Kenney, W.A.; Gambles, R.L.; Zsuffa, L.

    1992-01-01

    A study was carried out to: determine the factors affecting the cost of energy conversion feedstocks in short rotation intensive culture plantations of trees; determine the factors influencing biomass yield; identify interrelationships between the previous two objectives; present estimates of potential biomass yields and associated economics; and to identify gaps in the knowledge of the economics and yields of biomass production and their interrelationships. Reported costs for most aspects had a wide range. Currently, yields of 10-15 dry Mg/hectare/y are readily achievable. Using the cost and yield data, and assuming a biomass price of $40/dry Mg, a series of cash flow analyses were performed. For the low cost inputs, all scenarios were marginally profitable. For the high cost inputs, none of the scenarios were profitable. A current scenario, using figures for contract farming, was not profitable, however this system would break even with a yield of 23.3 dry Mg/hectare/y, within the range of some production clones. A future scenario using farm labour with increased productivity, product values, and machinery efficiencies yielded a profit-making situation. The addition of incentives increased profitability. There is great potential for the production of woody biomass in Canada as a feedstock for energy and other products. Continued and more intensive breeding and selection to develop high yielding stress tolerant clones, cost efficient harvesting systems, continued research into optimization of planting density, rotation length and cultural techniques, and characterization of promising clones with respect to nutrient-use efficiency, site requirements and pest/disease resistance are important areas for further work. 81 refs., 3 figs., 13 tabs

  13. Evaluation of polycross sweetpotato seedlings for root yield potential ...

    African Journals Online (AJOL)

    The study aimed at determining the root yield potential of the sweetpotato seedlings, the variation in storage root flesh colour and response of the storage roots to major pests and diseases attacking sweetpotato in the field .The experiment was carried out in the screen house and at the Eastern experimental field of National ...

  14. Sinusoidal potential cycling operation of a direct ethanol fuel cell to improving carbon dioxide yields

    Science.gov (United States)

    Majidi, Pasha; Pickup, Peter G.

    2014-12-01

    A direct ethanol fuel cell has been operated under sinusoidal (AC) potential cycling conditions in order to increase the yield of carbon dioxide and thereby increase cell efficiency relative to operation at a fixed potential. At 80 °C, faradaic yields of CO2 as high as 25% have been achieved with a PtRu anode catalyst, while the maximum CO2 production at constant potential was 13%. The increased yields under cycling conditions have been attributed to periodic oxidative stripping of adsorbed CO. These results will be important in the optimization of operating conditions for direct ethanol fuel cells, where the benefits of potential cycling are projected to increase as catalysts that produce CO2 more efficiently are implemented.

  15. Potential for yield in red clover (Trifolium pratense L. varieties

    Directory of Open Access Journals (Sweden)

    Vasiljević Sanja

    2010-01-01

    Full Text Available Red clover (Trifolium pratense L. is botanically a perennial, although it often behaves as a biennial. The crop usually lives 2 to 3 seasons in most clover-growing regions of the world and is generally conceded to be lacking in persistence. The objective of this investigation was to analyze the production potential and persistence of domestic and imported red clover varieties. Experiments were conducted at Rimski Šančevi Experiment Field during the period 2004-2006. The experimental materials were six varieties (K-17, Kolubara, Una, Viola, Start, Nike which were analyzed for the most important production characteristics: yield of green mass, dry matter yield and persistence. .

  16. Zero tillage: A potential technology to improve cotton yield

    Directory of Open Access Journals (Sweden)

    Abbas Hafiz Ghazanfar

    2016-01-01

    Full Text Available Zero tillage technology revealed with no use of any soil inverting technique to grow crops. The crop plant seed is planted in the soil directly after irrigation to make the soil soft without any replenishing in soil layers. A study was conducted to evaluate cotton genotypes FH-114 and FH-142 for the consecutive three years of growing seasons from 2013-15. The seed of both genotypes was sown with two date of sowing, 1 March and 1 May of each three years of sowing under three tillage treatments (zero tillage, minimum tillage and conventional tillage in triplicate completely randomized split-split plot design. It was found from results that significant differences were recorded for tillage treatments, date of sowing, genotypes and their interactions. Multivariate analysis was performed to evaluate the yield and it attributed traits for potential of FH-114 and FH-142 cotton genotypes. The genotype FH-142 was found with higher and batter performance as compared to FH-114 under zero tillage, minimum tillage and conventional tillage techniques. The traits bolls per plant, boll weight, fibre fineness, fibre strength, plant height, cotton yield per plant and sympodial branches per plant were found as most contributing traits towards cotton yield and production. It was also found that FH-142 gives higher output in terms of economic gain under zero tillage with 54% increase as compared to conventional tillage technique. It was suggested that zero tillage technology should be adopted to improve cotton yield and quality. It was also recommended that further study to evaluate zero tillage as potential technology should be performed with different regions, climate and timing throughout the world.

  17. Archaea produce lower yields of N2 O than bacteria during aerobic ammonia oxidation in soil.

    Science.gov (United States)

    Hink, Linda; Nicol, Graeme W; Prosser, James I

    2017-12-01

    Nitrogen fertilisation of agricultural soil contributes significantly to emissions of the potent greenhouse gas nitrous oxide (N 2 O), which is generated during denitrification and, in oxic soils, mainly by ammonia oxidisers. Although laboratory cultures of ammonia oxidising bacteria (AOB) and archaea (AOA) produce N 2 O, their relative activities in soil are unknown. This work tested the hypothesis that AOB dominate ammonia oxidation and N 2 O production under conditions of high inorganic ammonia (NH 3 ) input, but result mainly from the activity of AOA when NH 3 is derived from mineralisation. 1-octyne, a recently discovered inhibitor of AOB, was used to distinguish N 2 O production resulting from archaeal and bacterial ammonia oxidation in soil microcosms, and specifically inhibited AOB growth, activity and N 2 O production. In unamended soils, ammonia oxidation and N 2 O production were lower and resulted mainly from ammonia oxidation by AOA. The AOA N 2 O yield relative to nitrite produced was half that of AOB, likely due to additional enzymatic mechanisms in the latter, but ammonia oxidation and N 2 O production were directly linked in all treatments. Relative contributions of AOA and AOB to N 2 O production, therefore, reflect their respective contributions to ammonia oxidation. These results suggest potential mitigation strategies for N 2 O emissions from fertilised agricultural soils. © 2016 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  18. Effect of nitrogen and water deficit type on the yield gap between the potential and attainable wheat yield

    Directory of Open Access Journals (Sweden)

    Jiangang Liu

    2015-12-01

    Full Text Available Water deficit and N fertilizer are the two primary limiting factors for wheat yield in the North China plain, the most important winter wheat (Triticum aestivum L. production area in China. Analyzing the yield gap between the potential yield and the attainable yield can quantify the potential for increasing wheat production and exploring the limiting factors to yield gap in the high-yielding farming region of North China Plain. The Decision Support System for Agrotechnology Transfer (DSSAT model was used to identify methods to increase the grain yield and decrease the gap. In order to explore the impact of N and cultivars on wheat yield in the different drought types, the climate conditions during 1981 to 2011 growing seasons was categorized into low, moderate, and severe water deficit classes according to the anomaly percentage of the water deficit rate during the entire wheat growing season. There are differences (P < 0.0001 in the variations of the potential yields among three cultivars over 30 yr. For all three water deficit types, the more recent cultivars Jimai22 and Shijiazhuang8 had higher yields compared to the older 'Jinan17'. As the N fertilizer rate increased, the yield gap decreased more substantially during the low water deficit years because of the significant increase in attainable yield. Overall, the yield gaps were smaller with less water stress. Replacement of cultivars and appropriate N fertilizer application based on the forecasted drought types can narrow the yield gap effectively.

  19. Bird communities and biomass yields in potential bioenergy grasslands.

    Directory of Open Access Journals (Sweden)

    Peter J Blank

    Full Text Available Demand for bioenergy is increasing, but the ecological consequences of bioenergy crop production on working lands remain unresolved. Corn is currently a dominant bioenergy crop, but perennial grasslands could produce renewable bioenergy resources and enhance biodiversity. Grassland bird populations have declined in recent decades and may particularly benefit from perennial grasslands grown for bioenergy. We asked how breeding bird community assemblages, vegetation characteristics, and biomass yields varied among three types of potential bioenergy grassland fields (grass monocultures, grass-dominated fields, and forb-dominated fields, and assessed tradeoffs between grassland biomass production and bird habitat. We also compared the bird communities in grassland fields to nearby cornfields. Cornfields had few birds compared to perennial grassland fields. Ten bird Species of Greatest Conservation Need (SGCN were observed in perennial grassland fields. Bird species richness and total bird density increased with forb cover and were greater in forb-dominated fields than grass monocultures. SGCN density declined with increasing vertical vegetation density, indicating that tall, dense grassland fields managed for maximum biomass yield would be of lesser value to imperiled grassland bird species. The proportion of grassland habitat within 1 km of study sites was positively associated with bird species richness and the density of total birds and SGCNs, suggesting that grassland bioenergy fields may be more beneficial for grassland birds if they are established near other grassland parcels. Predicted total bird density peaked below maximum biomass yields and predicted SGCN density was negatively related to biomass yields. Our results indicate that perennial grassland fields could produce bioenergy feedstocks while providing bird habitat. Bioenergy grasslands promote agricultural multifunctionality and conservation of biodiversity in working landscapes.

  20. Studies on seed yield potential of some selected kenaf (Hibiscus ...

    African Journals Online (AJOL)

    SAM

    2014-06-11

    Jun 11, 2014 ... Kenaf seed yield depends on morpho-physiological traits between varieties, .... separated using Duncan's Multiple Range Test (DMRT) at 5% ... Mean squares derived from combined analysis of variance for seed yield and yield components in 20 .... environment interaction and yield stability in winter wheat.

  1. Seed yield components and their potential interaction in grasses - to what extend does seed weigth influence yield?

    DEFF Research Database (Denmark)

    Boelt, B; Gislum, R

    2010-01-01

     In a first-year seed crop of red fescue (Festuca rubra L.) the degree of lodging was controlled by the use of Moddus (Trinexapac-ethyl). Seed weight was found to increase by the decreasing degree of lodging prior to harvest. The higher seed weights were accompanied by higher yields even though...... the number of reproductive tillers and floret site utilization (FSU) were unaffected by the treatments. Seed yield is affected by several yield components and reflects the interaction between the seed yield potential (e.g. number of reproductive tillers, number of spikelets and florets/spikelet per...... reproductive tiller), the utilization of the potential (e.g. seed set, seed weight) and the realization of the seed yield potential, defined as the number of florets forming a saleable seed. The realization of the seed yield potential is affected by seed retention, seed weight and other traits associated...

  2. Oil palm natural diversity and the potential for yield improvement

    Science.gov (United States)

    Barcelos, Edson; Rios, Sara de Almeida; Cunha, Raimundo N. V.; Lopes, Ricardo; Motoike, Sérgio Y.; Babiychuk, Elena; Skirycz, Aleksandra; Kushnir, Sergei

    2015-01-01

    African oil palm has the highest productivity amongst cultivated oleaginous crops. Species can constitute a single crop capable to fulfill the growing global demand for vegetable oils, which is estimated to reach 240 million tons by 2050. Two types of vegetable oil are extracted from the palm fruit on commercial scale. The crude palm oil and kernel palm oil have different fatty acid profiles, which increases versatility of the crop in industrial applications. Plantations of the current varieties have economic life-span around 25–30 years and produce fruits around the year. Thus, predictable annual palm oil supply enables marketing plans and adjustments in line with the economic forecasts. Oil palm cultivation is one of the most profitable land uses in the humid tropics. Oil palm fruits are the richest plant source of pro-vitamin A and vitamin E. Hence, crop both alleviates poverty, and could provide a simple practical solution to eliminate global pro-vitamin A deficiency. Oil palm is a perennial, evergreen tree adapted to cultivation in biodiversity rich equatorial land areas. The growing demand for the palm oil threatens the future of the rain forests and has a large negative impact on biodiversity. Plant science faces three major challenges to make oil palm the key element of building the future sustainable world. The global average yield of 3.5 tons of oil per hectare (t) should be raised to the full yield potential estimated at 11–18t. The tree architecture must be changed to lower labor intensity and improve mechanization of the harvest. Oil composition should be tailored to the evolving needs of the food, oleochemical and fuel industries. The release of the oil palm reference genome sequence in 2013 was the key step toward this goal. The molecular bases of agronomically important traits can be and are beginning to be understood at the single base pair resolution, enabling gene-centered breeding and engineering of this remarkable crop. PMID:25870604

  3. Oil palm natural diversity and the potential for yield improvement.

    Science.gov (United States)

    Barcelos, Edson; Rios, Sara de Almeida; Cunha, Raimundo N V; Lopes, Ricardo; Motoike, Sérgio Y; Babiychuk, Elena; Skirycz, Aleksandra; Kushnir, Sergei

    2015-01-01

    African oil palm has the highest productivity amongst cultivated oleaginous crops. Species can constitute a single crop capable to fulfill the growing global demand for vegetable oils, which is estimated to reach 240 million tons by 2050. Two types of vegetable oil are extracted from the palm fruit on commercial scale. The crude palm oil and kernel palm oil have different fatty acid profiles, which increases versatility of the crop in industrial applications. Plantations of the current varieties have economic life-span around 25-30 years and produce fruits around the year. Thus, predictable annual palm oil supply enables marketing plans and adjustments in line with the economic forecasts. Oil palm cultivation is one of the most profitable land uses in the humid tropics. Oil palm fruits are the richest plant source of pro-vitamin A and vitamin E. Hence, crop both alleviates poverty, and could provide a simple practical solution to eliminate global pro-vitamin A deficiency. Oil palm is a perennial, evergreen tree adapted to cultivation in biodiversity rich equatorial land areas. The growing demand for the palm oil threatens the future of the rain forests and has a large negative impact on biodiversity. Plant science faces three major challenges to make oil palm the key element of building the future sustainable world. The global average yield of 3.5 tons of oil per hectare (t) should be raised to the full yield potential estimated at 11-18t. The tree architecture must be changed to lower labor intensity and improve mechanization of the harvest. Oil composition should be tailored to the evolving needs of the food, oleochemical and fuel industries. The release of the oil palm reference genome sequence in 2013 was the key step toward this goal. The molecular bases of agronomically important traits can be and are beginning to be understood at the single base pair resolution, enabling gene-centered breeding and engineering of this remarkable crop.

  4. Oil palm natural diversity and the potential for yield improvement

    Directory of Open Access Journals (Sweden)

    Edson eBarcelos

    2015-03-01

    Full Text Available African oil palm has the highest productivity amongst cultivated oleaginous crops. Species can constitute a single crop capable to fulfil the growing global demand for vegetable oils, which is estimated to reach 240 million tons by 2050. Two types of vegetable oil are extracted from the palm fruit on commercial scale. The crude palm oil and kernel palm oil have different fatty acid profiles, which increases versatility of the crop in industrial applications. Plantations of the current varieties have economic life-span around 25-30 years and produce fruits around the year. Thus, predictable annual palm oil supply enables marketing plans and adjustments in line with the economic forecasts. Oil palm cultivation is one of the most profitable land uses in the humid tropics. Oil palm fruits are the richest plant source of pro-vitamin A and vitamin E. Hence, crop both alleviates poverty, and could provide a simple practical solution to eliminate global pro-vitamin A deficiency. Oil palm is a perennial, evergreen tree adapted to cultivation in biodiversity rich equatorial land areas. The growing demand for the palm oil threatens the future of the rain forests and has a large negative impact on biodiversity. Plant science faces three major challenges to make oil palm the key element of building the future sustainable world. The global average yield of 3.5 tons of oil per hectare (t should be raised to the full yield potential estimated at 11-18t. The tree architecture must be changed to lower labor intensity and improve mechanization of the harvest. Oil composition should be tailored to the evolving needs of the food, oleochemical and fuel industries. The release of the oil palm reference genome sequence in 2013 was the key step towards this goal. The molecular bases of agronomically important traits can be and are beginning to be understood at the single base pair resolution, enabling gene-centered breeding and engineering of this remarkable crop.

  5. Nitrate radical oxidation of γ-terpinene: hydroxy nitrate, total organic nitrate, and secondary organic aerosol yields

    Science.gov (United States)

    Slade, Jonathan H.; de Perre, Chloé; Lee, Linda; Shepson, Paul B.

    2017-07-01

    Polyolefinic monoterpenes represent a potentially important but understudied source of organic nitrates (ONs) and secondary organic aerosol (SOA) following oxidation due to their high reactivity and propensity for multi-stage chemistry. Recent modeling work suggests that the oxidation of polyolefinic γ-terpinene can be the dominant source of nighttime ON in a mixed forest environment. However, the ON yields, aerosol partitioning behavior, and SOA yields from γ-terpinene oxidation by the nitrate radical (NO3), an important nighttime oxidant, have not been determined experimentally. In this work, we present a comprehensive experimental investigation of the total (gas + particle) ON, hydroxy nitrate, and SOA yields following γ-terpinene oxidation by NO3. Under dry conditions, the hydroxy nitrate yield = 4(+1/-3) %, total ON yield = 14(+3/-2) %, and SOA yield ≤ 10 % under atmospherically relevant particle mass loadings, similar to those for α-pinene + NO3. Using a chemical box model, we show that the measured concentrations of NO2 and γ-terpinene hydroxy nitrates can be reliably simulated from α-pinene + NO3 chemistry. This suggests that NO3 addition to either of the two internal double bonds of γ-terpinene primarily decomposes forming a relatively volatile keto-aldehyde, reconciling the small SOA yield observed here and for other internal olefinic terpenes. Based on aerosol partitioning analysis and identification of speciated particle-phase ON applying high-resolution liquid chromatography-mass spectrometry, we estimate that a significant fraction of the particle-phase ON has the hydroxy nitrate moiety. This work greatly contributes to our understanding of ON and SOA formation from polyolefin monoterpene oxidation, which could be important in the northern continental US and the Midwest, where polyolefinic monoterpene emissions are greatest.

  6. Studies on seed yield potential of some selected kenaf ( Hibiscus ...

    African Journals Online (AJOL)

    Kenaf seed yield depends on morpho-physiological traits between varieties, and the interaction between genotype and the environment. Studies were conducted in Ibadan, Ilora and Kisi stations of the Institute of Agricultural Research and Training (IAR&T), Obafemi Awolowo University, Moor Plantation, Ibadan, Oyo State, ...

  7. Potential of multiseeded mutant (msd) to boost sorghum grain yield

    Science.gov (United States)

    Seed number per plant is an important determinant of the grain yield in cereal and other crops. We have isolated a class of multiseeded (msd) sorghum (Sorghum bicolor L. Moench) mutants that are capable of producing three times the seed number and twice the seed weight per panicle as compared with t...

  8. Distribution of genes associated with yield potential and water ...

    Indian Academy of Sciences (India)

    on the FMs related to yield and water saving in wheat. Till date, six loci ..... Hu Y., Moiwo J. P., Yang Y., Han S. and Yang Y. 2010 Agricul- tural water-saving ... Lyu L., Hu Y., Li Y. and Wang P. 2007 Effect of irrigation treatment on water use ... Zhang Y. J., Fan P. S., Zhang X., Chen C. J. and Zhou M. G. 2009. Quantification of ...

  9. Optimization of the size and yield of graphene oxide sheets in the exfoliation step

    OpenAIRE

    Botas, Cristina; Pérez, A.M. (Ana); Álvarez, Patricia; Santamaría, Ricardo; Granda, Marcos; Blanco, Clara; Menéndez, Rosa

    2017-01-01

    In this paper we demonstrate that the yield and size of the graphene oxide sheets (GO) obtained by sonication of graphite oxide (GrO) can be optimized not only by selecting the appropriate exfoliation conditions but also as a function of the crystalline structure of the parent graphite. A larger crystal size in the parent graphite favors GrO exfoliation and yields larger sheets in shorter sonication times, independently of the oxygen content of the GrO. A maximum yield of GO is obtained in al...

  10. Myeloperoxidase potentiates nitric oxide-mediated nitrosation.

    Science.gov (United States)

    Lakshmi, Vijaya M; Nauseef, William M; Zenser, Terry V

    2005-01-21

    Nitrosation is an important reaction elicited by nitric oxide (NO). To better understand how nitrosation occurs in biological systems, we assessed the effect of myeloperoxidase (MPO), a mediator of inflammation, on nitrosation observed during NO autoxidation. Nitrosation of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ; 10 mum) to 2-nitrosoamino-3-methylimidazo[4,5-f]quinoline (N-NO-IQ) was monitored by HPLC. Using the NO donor spermine NONOate at pH 7.4, MPO potentiated N-NO-IQ formation. The minimum effective quantity of necessary components was 8.5 nm MPO, 0.25 mum H(2)O(2)/min, and 0.024 mum NO/min. Autoxidation was only detected at >/=1.2 mum NO/min. MPO potentiation was not affected by a 40-fold excess flux of H(2)O(2) over NO or less than a 2.4-fold excess flux of NO over H(2)O(2). Potentiation was due to an 8.8-fold increased affinity of MPO-derived nitrosating species for IQ. Autoxidation was inhibited by azide, suggesting involvement of the nitrosonium ion, NO(+). MPO potentiation was inhibited by NADH, but not azide, suggesting oxidative nitrosylation with NO(2)(.) or an NO(2)(.)-like species. MPO nonnitrosative oxidation of IQ with 0.3 mm NO(2)(-) at pH 5.5 was inhibited by azide, but not NADH, demonstrating differences between MPO oxidation of IQ with NO compared with NO(2)(-). Using phorbol ester-stimulated human neutrophils, N-NO-IQ formation was increased with superoxide dismutase and inhibited by catalase and NADH, but not NaN(3). This is consistent with nitrosation potentiation by MPO, not peroxynitrite. Increased N-NO-IQ formation was not detected with polymorphonuclear neutrophils from two unrelated MPO-deficient patients. Results suggest that the highly diffusible stable gas NO could initiate nitrosation at sites of neutrophil infiltration.

  11. Effects of Nano-Zinc oxide and Seed Inoculation by Plant Growth Promoting Rhizobacteria (PGPR on Yield, Yield Components and Grain Filling Period of Soybean (Glycine max L.

    Directory of Open Access Journals (Sweden)

    R. Seyed Sharifi

    2016-02-01

    Full Text Available Introduction Utilizing biological fertilizer is a proper and cheap method for crop production. Potentially, soybean can be used as biological fertilizers and seed inoculation. Zinc is an essential element that have positive effects on plant growth and its development. Canola, sunflower, soybean and safflower are the main cultivated oilseeds in Iran. Soybean production in Iran is very low as compared to other countries. One of the most effective factor in increasing the soybean yield is seed inoculation with plant growth promoting rhizobacteria (PGPR and application of Zinc fertilizer. Some of the benefits provided by PGPR are the ability to produce gibberellic acid, cytokinins and ethylene, N2 fixation, solubilization of mineral phosphates and other nutrients (56. Numerous studies have shown a substantial increase in dry matter accumulation and seed yield following inoculation with PGPR. Seyed Sharifi (45 reported that seed inoculation with Azotobacter chroococcum strain 5 increased all of the growth indices such as total dry matter, crop growth rate and relative growth rate. Increasing and extending the role of biofertilizers such as Rhizobium can reduce the need for chemical fertilizers and decrease adverse environmental effects. Therefore, in the development and implementation of sustainable agricultural techniques, biofertilization has great importance in alleviating environmental pollution and deterioration of the nature. As a legume, soybean can obtain a significant portion (4-85% of its nitrogen requirement through symbiotic N2 fixation when grown in association with effective and compatible Rhizobium strains. Since there is little available information on nano-zinc oxide and seed inoculation by plant growth promoting rhizobacteria (PGPR on yield in the agro-ecological growing zones of Ardabil province of Iran. Therefore, this research was conducted to investigate the effects of nano-zinc oxide and seed inoculation with plant growth

  12. Potential well yields from unconsolidated deposits in the lower Hudson and Delaware River basins, New York

    Science.gov (United States)

    Wolcott, Stephen W.

    1987-01-01

    A comprehensive groundwater protection plan, developed by the New York State Department of Environmental Conservation in 1985, identified the need to delineate significant aquifers within the state. A map of the unconsolidated aquifers in the lower Hudson and Delaware River basins was compiled from available data on the surficial geology and well yields. It delineates the significant unconsolidated aquifers and indicates the potential yield of wells that tap these aquifers. The potential well yield is categorized into three ranges: 100 gal/min. No yield range is given for till, but some large diameter or dug wells in till may yield up 10 gal/min. (Lantz-PTT)

  13. Isoprene oxidation by nitrate radical: alkyl nitrate and secondary organic aerosol yields

    Directory of Open Access Journals (Sweden)

    A. W. Rollins

    2009-09-01

    Full Text Available Alkyl nitrates and secondary organic aerosol (SOA produced during the oxidation of isoprene by nitrate radicals has been observed in the SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber chamber. A 16 h dark experiment was conducted with temperatures at 289–301 K, and maximum concentrations of 11 ppb isoprene, 62.4 ppb O3 and 31.1 ppb NOx. We find the yield of nitrates is 70±8% from the isoprene + NO3 reaction, and the yield for secondary dinitrates produced in the reaction of primary isoprene nitrates with NO3 is 40±20%. We find an effective rate constant for reaction of NO3 with the group of first generation oxidation products to be 7×10−14 molecule−1 cm3 s−1. At the low total organic aerosol concentration in the chamber (max=0.52 μg m−3 we observed a mass yield (ΔSOA mass/Δisoprene mass of 2% for the entire 16 h experiment. However a comparison of the timing of the observed SOA production to a box model simulation of first and second generation oxidation products shows that the yield from the first generation products was <0.7% while the further oxidation of the initial products leads to a yield of 14% (defined as ΔSOA/Δisoprene2x where Δisoprene2x is the mass of isoprene which reacted twice with NO3. The SOA yield of 14% is consistent with equilibrium partitioning of highly functionalized C5 products of isoprene oxidation.

  14. Photo-oxidation of histidine peptides yields high concentrations of unstable peroxides

    International Nuclear Information System (INIS)

    Policarpio, V.V.; Hawkins, C.L.; Davies, M.J.

    2003-01-01

    Oxidation of proteins by UV, and visible light in the presence of sensitizers, results in side chain modification as well as aggregation and fragmentation. In particular, singlet oxygen has been reported to oxidize Met, Trp, Tyr, Cys and His side chains in a selective manner. In this study the oxidation of histidine and its derivatives, and His-containing peptides is examined using a range of sensitizers, to determine whether peroxides are major intermediates, and the mechanism of formation of these species. Visible light-sensitised oxidation of Gly-His-Gly in the presence of oxygen and rose bengal gives unstable substrate-derived peroxides with the peroxide yield increasing with increasing photolysis time. Similar behaviour was detected with other photosensitizers, though the peroxide yields varied with the sensitizer at identical concentrations with rose bengal > aluminium phthalocyanine > hematoporphyrin IX > zinc phthalocyanine > tetrakisporphine. The peroxide yield was decreased in the presence of azide and enhanced when deuterium oxide was employed as the solvent, consistent with peroxide formation being singlet oxygen mediated. Experiments using anoxic conditions gave low yields of peroxides confirming the oxygen-dependence of these reactions. HPLC analysis showed rapid loss of the parent peptide, with subsequent formation of both stable and unstable products; these are currently being characterized by MS and NMR. Similar behavior has been observed with other His derivatives. The yield of singlet oxygen formed in these reactions has been estimated using a bleaching assay (N, N-dimethyl-4-nitrosoaniline). Quantification of singlet oxygen formation and Gly-His-Gly derived peroxide during rose bengal-mediated photooxidation indicated a conversion efficiency of the initial singlet oxygen into substrate-derived peroxides of ca. 75% indicating that peroxide formation is a highly efficient and major reaction pathway

  15. Do soil organic carbon levels affect potential yields and nitrogen use efficiency?

    DEFF Research Database (Denmark)

    Oelofse, Myles; Markussen, Bo; Knudsen, Leif

    2015-01-01

    Soil organic carbon (SOC) is broadly recognised as an important parameter affecting soil quality, and can therefore contribute to improving a number of soil properties that influence crop yield. Previous research generally indicates that soil organic carbon has positive effects on crop yields......, the yield with no fertiliser N application and the N use efficiency would be positively affected by SOC level. A statistical model was developed to explore relationships between SOC and potential yield, yields at zero N application and N use efficiency (NUE). The model included a variety of variables...

  16. A potential biomarker for fatigue: Oxidative stress and anti-oxidative activity.

    Science.gov (United States)

    Fukuda, Sanae; Nojima, Junzo; Motoki, Yukari; Yamaguti, Kouzi; Nakatomi, Yasuhito; Okawa, Naoko; Fujiwara, Kazumi; Watanabe, Yasuyoshi; Kuratsune, Hirohiko

    2016-07-01

    We sought to determine whether oxidative stress and anti-oxidative activity could act as biomarkers that discriminate patients with chronic fatigue syndrome (CFS) from healthy volunteers at acute and sub-acute fatigue and resting conditions. We calculated the oxidative stress index (OSI) from reactive oxygen metabolites-derived compounds (d-ROMs) and the biological antioxidant potential (BAP). We determined changes in d-ROMs, BAP, and OSI in acute and sub-acute fatigue in two healthy groups, and compared their values at rest between patients with CFS (diagnosed by Fukuda 1994 criteria) and another group of healthy controls. Following acute fatigue in healthy controls, d-ROMs and OSI increased, and BAP decreased. Although d-ROMs and OSI were significantly higher after sub-acute fatigue, BAP did not decrease. Resting condition yielded higher d-ROMs, higher OSI, and lower BAP in patients with CFS than in healthy volunteers, but lower d-ROMs and OSI when compared with sub-acute controls. BAP values did not significantly differ between patients with CFS and controls in the sub-acute condition. However, values were significantly higher than in the resting condition for controls. Thus, measured of oxidative stress (d-ROMS) and anti-oxidative activity (BAP) might be useful for discriminating acute, sub-acute, and resting fatigue in healthy people from patients with CFS, or for evaluating fatigue levels in healthy people. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. [Spatial-temporal variations of spring maize potential yields in a changing climate in Northeast China.

    Science.gov (United States)

    Liu, Zhi Juan; Yang, Xiao Guang; Lyu, Shuo; Wang, Jing; Lin, Xiao Mao

    2018-01-01

    Based on meteorological data, agro-meteorological observations, and agricultural statistical data in Northeast China (NEC), by using the validated Agricultural Production System sIMulator (APSIM-maize), the potential, attainable, potential farmers' and actual farmers' yields of spring maize during the period 1961 to 2015 were analyzed, and the effects of climate variation on maize potential yield in NEC were quantified. Results indicated that the potential yield of spring maize was 12.2 t·hm -2 during the period 1961 to 2015, with those in northeast being lower than southwest within the study region. The attainable yield of spring maize was 11.3 t·hm -2 , and showed a similar spatial distribution with potential yield. Under the current farmers' management practices, mean simulated potential and actual farmers' yields were 6.5 and 4.5 t·hm -2 , respectively. Assuming there were no changes in cultivars and management practices in NEC, the mean potential, attainable, and potential farmers' yields of spring maize would decrease by 0.34, 0.25 and 0.10 t·hm -2 per decade in NEC. However, the actual farmers' yields increased with the value of 1.27 t·hm -2 per decade averaged over NEC. Due to climate variation, year-to-year variations of spring maize potential, attainable, and potential farmers' yields were significant, ranging from 10.0 to 14.4, 9.8 to 13.3, 4.4 to 8.5 t·hm -2 , respectively.

  18. Mass yields of secondary organic aerosols from the oxidation of α-pinene and real plant emissions

    Directory of Open Access Journals (Sweden)

    J. N. Smith

    2011-02-01

    Full Text Available Biogenic volatile organic compounds (VOCs are a significant source of global secondary organic aerosol (SOA; however, quantifying their aerosol forming potential remains a challenge. This study presents smog chamber laboratory work, focusing on SOA formation via oxidation of the emissions of two dominant tree species from boreal forest area, Scots pine (Pinus sylvestris L. and Norway spruce (Picea abies, by hydroxyl radical (OH and ozone (O3. Oxidation of α-pinene was also studied as a reference system. Tetramethylethylene (TME and 2-butanol were added to control OH and O3 levels, thereby allowing SOA formation events to be categorized as resulting from either OH-dominated or O3-initiated chemistry. SOA mass yields from α-pinene are consistent with previous studies while the yields from the real plant emissions are generally lower than that from α-pinene, varying from 1.9% at an aerosol mass loading of 0.69 μg m−3 to 17.7% at 26.0 μg m−3. Mass yields from oxidation of real plant emissions are subject to the interactive effects of the molecular structures of plant emissions and their reaction chemistry with OH and O3, which lead to variations in condensable product volatility. SOA formation can be reproduced with a two-product gas-phase partitioning absorption model in spite of differences in the source of oxidant species and product volatility in the real plant emission experiments. Condensable products from OH-dominated chemistry showed a higher volatility than those from O3-initiated systems during aerosol growth stage. Particulate phase products became less volatile via aging process which continued after input gas-phase oxidants had been completely consumed.

  19. High-Yield Synthesis of Zinc Oxide Nanoparticles from Bicontinuous Microemulsions

    Directory of Open Access Journals (Sweden)

    S. López-Cuenca

    2011-01-01

    Full Text Available The high-yield synthesis of zinc oxide (ZnO primary nanoparticles with high purity and with diameters between 6 and 22 nm using bicontinuous microemulsions is reported in this work. The ZnO nanoparticles were made by hydrolysis of Zn(NO32 with NaOH aqueous solution and precipitation, followed by calcination of the precipitate. Higher yields and productivities of ZnO nanoparticles were obtained compared to values produced with w/o micremulsions reported in the literature. Particles were characterized by transmission electronic microscopy (TEM, X-ray diffraction, and atomic absorption spectroscopy.

  20. A short proof that the Coulomb-gauge potentials yield the retarded fields

    Energy Technology Data Exchange (ETDEWEB)

    Heras, Jose A, E-mail: herasgomez@gmail.co [Universidad Autonoma Metropolitana, Unidad Azcapotzalco, Av. San Pablo No. 180, Col. Reynosa, Mexico D. F. 02200 (Mexico)

    2011-01-15

    A short demonstration that the potentials in the Coulomb gauge yield the retarded electric and magnetic fields is presented. This demonstration is relatively simple and can be presented in an advanced undergraduate course of electromagnetic theory.

  1. A short proof that the Coulomb-gauge potentials yield the retarded fields

    International Nuclear Information System (INIS)

    Heras, Jose A

    2011-01-01

    A short demonstration that the potentials in the Coulomb gauge yield the retarded electric and magnetic fields is presented. This demonstration is relatively simple and can be presented in an advanced undergraduate course of electromagnetic theory.

  2. HIGH YIELD GENETICALLY MODIFIED WHEAT IN GERMANY: SOCIO ECONOMIC ASSESSMENT OF ITS POTENTIAL

    OpenAIRE

    Wree, Philipp; Sauer, Johannes

    2015-01-01

    High Yield Genetically Modified Wheat (HOSUT) HOSUT lines are an innovation in wheat breeding based on biotechnology with an incremental yield potential of ca. 28% compared to conventional wheat varieties. We apply the real option concept of Maximum Incremental Social Tolerable Irreversible Costs (MISTICs) to do an ex-ante assessment of the socioeconomic potential of HOSUT lines for Germany. We analyze the cost and benefits to farmer and society within two scenarios. Our results of our scenar...

  3. Yield-scaled global warming potential of two irrigation management systems in a highly productive rice system

    Directory of Open Access Journals (Sweden)

    Silvana Tarlera

    2016-02-01

    Full Text Available ABSTRACT Water management impacts both methane (CH4 and nitrous oxide (N2O emissions from rice paddy fields. Although controlled irrigation is one of the most important tools for reducing CH4emission in rice production systems it can also increase N2O emissions and reduce crop yields. Over three years, CH4 and N2O emissions were measured in a rice field in Uruguay under two different irrigation management systems, using static closed chambers: conventional water management (continuous flooding after 30 days of emergence, CF30; and an alternative system (controlled deficit irrigation allowing for wetting and drying, AWDI. AWDI showed mean cumulative CH4 emission values of 98.4 kg CH4 ha−1, 55 % lower compared to CF30, while no differences in nitrous oxide emissions were observed between treatments ( p > 0.05. No yield differences between irrigation systems were observed in two of the rice seasons ( p > 0.05 while AWDI promoted yield reduction in one of the seasons ( p< 0.05. When rice yield and greenhouse gases (GHG emissions were considered together, the AWDI irrigation system allowed for lower yield-scaled total global warming potential (GWP. Higher irrigation water productivity was achieved under AWDI in two of the three rice seasons. These findings suggest that AWDI could be an option for reducing GHG emissions and increasing irrigation water productivity. However, AWDI may compromise grain yield in certain years, reflecting the importance of the need for fine tuning of this irrigation strategy and an assessment of the overall tradeoff between relationships in order to promote its adoption by farmers.

  4. Kinetics, Mechanism, and Secondary Organic Aerosol Yield of Aqueous Phase Photo-oxidation of α-Pinene Oxidation Products.

    Science.gov (United States)

    Aljawhary, Dana; Zhao, Ran; Lee, Alex K Y; Wang, Chen; Abbatt, Jonathan P D

    2016-03-10

    Formation of secondary organic aerosol (SOA) involves atmospheric oxidation of volatile organic compounds (VOCs), the majority of which are emitted from biogenic sources. Oxidation can occur not only in the gas-phase but also in atmospheric aqueous phases such as cloudwater and aerosol liquid water. This study explores for the first time the aqueous-phase OH oxidation chemistry of oxidation products of α-pinene, a major biogenic VOC species emitted to the atmosphere. The kinetics, reaction mechanisms, and formation of SOA compounds in the aqueous phase of two model compounds, cis-pinonic acid (PIN) and tricarballylic acid (TCA), were investigated in the laboratory; TCA was used as a surrogate for 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA), a known α-pinene oxidation product. Aerosol time-of-flight chemical ionization mass spectrometry (Aerosol-ToF-CIMS) was used to follow the kinetics and reaction mechanisms at the molecular level. Room-temperature second-order rate constants of PIN and TCA were determined to be 3.3 (± 0.5) × 10(9) and 3.1 (± 0.2) × 10(8) M(-1) s(-1), respectively, from which were estimated their condensed-phase atmospheric lifetimes. Aerosol-ToF-CIMS detected a large number of products leading to detailed reaction mechanisms for PIN and MBTCA. By monitoring the particle size distribution after drying, the amount of SOA material remaining in the particle phase was determined. An aqueous SOA yield of 40 to 60% was determined for PIN OH oxidation. Although recent laboratory studies have focused primarily on aqueous-phase processing of isoprene-related compounds, we demonstrate that aqueous formation of SOA materials also occurs from monoterpene oxidation products, thus representing an additional source of biogenically driven aerosol formation.

  5. Calculation of total free energy yield as an alternative approach for predicting the importance of potential chemolithotrophic reactions in geothermal springs.

    Science.gov (United States)

    Dodsworth, Jeremy A; McDonald, Austin I; Hedlund, Brian P

    2012-08-01

    To inform hypotheses regarding the relative importance of chemolithotrophic metabolisms in geothermal environments, we calculated free energy yields of 26 chemical reactions potentially supporting chemolithotrophy in two US Great Basin hot springs, taking into account the effects of changing reactant and product activities on the Gibbs free energy as each reaction progressed. Results ranged from 1.2 × 10(-5) to 3.6 J kg(-1) spring water, or 3.7 × 10(-5) to 11.5 J s(-1) based on measured flow rates, with aerobic oxidation of CH(4) or NH4 + giving the highest average yields. Energy yields calculated without constraining pH were similar to those at constant pH except for reactions where H(+) was consumed, which often had significantly lower yields when pH was unconstrained. In contrast to the commonly used normalization of reaction chemical affinities per mole of electrons transferred, reaction energy yields for a given oxidant varied by several orders of magnitude and were more sensitive to differences in the activities of products and reactants. The high energy yield of aerobic ammonia oxidation is consistent with previous observations of significant ammonia oxidation rates and abundant ammonia-oxidizing archaea in sediments of these springs. This approach offers an additional lens through which to view the thermodynamic landscape of geothermal springs. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  6. Limonene ozonolysis in the presence of nitric oxide: Gas-phase reaction products and yields

    Science.gov (United States)

    Ham, Jason E.; Harrison, Joel C.; Jackson, Stephen R.; Wells, J. R.

    2016-05-01

    The reaction products from limonene ozonolysis were investigated using the new carbonyl derivatization agent, O-tert-butylhydroxylamine hydrochloride (TBOX). With ozone (O3) as the limiting reagent, five carbonyl compounds were detected. The yields of the carbonyl compounds are discussed with and without the presence of a hydroxyl radical (OHrad) scavenger, giving insight into the influence secondary OH radicals have on limonene ozonolysis products. The observed reaction product yields for limonaketone (LimaKet), 7-hydroxyl-6-oxo-3-(prop-1-en-2-yl)heptanal (7H6O), and 2-acetyl-5-oxohexanal (2A5O) were unchanged suggesting OHrad generated by the limonene + O3 reaction does not contribute to their formation. The molar yields of 3-isopropenyl-6-oxo-heptanal (IPOH) and 3-acetyl-6-oxoheptanal (3A6O) decreased by 68% and >95%; respectively, when OHrad was removed. This suggests that OHrad radicals significantly impact the formation of these products. Nitric oxide (NO) did not significantly affect the molar yields of limonaketone or IPOH. However, NO (20 ppb) considerably decreased the molar reaction product yields of 7H6O (62%), 2A5O (63%), and 3A6O (47%), suggesting NO reacted with peroxyl intermediates, generated during limonene ozonolysis, to form other carbonyls (not detected) or organic nitrates. These studies give insight into the transformation of limonene and its reaction products that can lead to indoor exposures.

  7. Potential yields of wells in unconsolidated aquifers in upstate New York-- Niagara sheet

    Science.gov (United States)

    Miller, Todd S.

    1988-01-01

    This map depicts the locations and potential well yields of unconsolidated aquifers in western New York at a scale of 1:250 ,000. It also delineates segments of aquifers that are used for public water supplies and designated by the New York State Department of Environmental Conservation as ' Primary Water Supply Aquifers. ' The map also lists published reports that give detailed information on each area. Most aquifers were deposited in low areas, such as valleys and plains, during deglaciation of the region. Thick, permeable, well-sorted sand and gravel units yield large quantities of water - more than 100 gal/min - to properly constructed wells. Thin sand units and sand and gravel units and thicker gravel units that have a large content of silt and fine sand yield moderate amounts of water, 10 to 100 gal/min. Dug wells that tap till or lacustrine deposits yield less than 5 gal/min. Well yields from bedrock are not indicated. (USGS)

  8. Nitrogen rate strategies for reducing yield-scaled nitrous oxide emissions in maize

    Science.gov (United States)

    Zhao, Xu; Nafziger, Emerson D.; Pittelkow, Cameron M.

    2017-12-01

    Mitigating nitrogen (N) losses from agriculture without negatively impacting crop productivity is a pressing environmental and economic challenge. Reductions in N fertilizer rate are often highlighted as a solution, yet the degree to which crop yields and economic returns may be impacted at the field-level remains unclear, in part due to limited data availability. Farmers are risk averse and potential yield losses may limit the success of voluntary N loss mitigation protocols, thus understanding field-level yield tradeoffs is critical to inform policy development. Using a case study of soil N2O mitigation in the US Midwest, we conducted an ex-post assessment of two economic and two environmental N rate reduction strategies to identify promising practices for maintaining maize yields and economic returns while reducing N2O emissions per unit yield (i.e. yield-scaled emissions) compared to an assumed baseline N input level. Maize yield response data from 201 on-farm N rate experiments were combined with an empirical equation predicting N2O emissions as a function of N rate. Results indicate that the economic strategy aimed at maximizing returns to N (MRTN) led to moderate but consistent reductions in yield-scaled N2O emissions with small negative impacts on yield and slight increases in median returns. The economic optimum N rate strategy reduced yield-scaled N2O emissions in 75% of cases but increased them otherwise, challenging the assumption that this strategy will automatically reduce environmental impacts per unit production. Both environmental strategies, one designed to increase N recovery efficiency and one to balance N inputs with grain N removal, further reduced yield-scaled N2O emissions but were also associated with negative yield penalties and decreased returns. These results highlight the inherent tension between achieving agronomic and economic goals while reducing environmental impacts which is often overlooked in policy discussions. To enable the

  9. Ecological intensification of cereal production systems: yield potential, soil quality, and precision agriculture.

    Science.gov (United States)

    Cassman, K G

    1999-05-25

    Wheat (Triticum aestivum L.), rice (Oryza sativa L.), and maize (Zea mays L.) provide about two-thirds of all energy in human diets, and four major cropping systems in which these cereals are grown represent the foundation of human food supply. Yield per unit time and land has increased markedly during the past 30 years in these systems, a result of intensified crop management involving improved germplasm, greater inputs of fertilizer, production of two or more crops per year on the same piece of land, and irrigation. Meeting future food demand while minimizing expansion of cultivated area primarily will depend on continued intensification of these same four systems. The manner in which further intensification is achieved, however, will differ markedly from the past because the exploitable gap between average farm yields and genetic yield potential is closing. At present, the rate of increase in yield potential is much less than the expected increase in demand. Hence, average farm yields must reach 70-80% of the yield potential ceiling within 30 years in each of these major cereal systems. Achieving consistent production at these high levels without causing environmental damage requires improvements in soil quality and precise management of all production factors in time and space. The scope of the scientific challenge related to these objectives is discussed. It is concluded that major scientific breakthroughs must occur in basic plant physiology, ecophysiology, agroecology, and soil science to achieve the ecological intensification that is needed to meet the expected increase in food demand.

  10. High yield fabrication of chemically reduced graphene oxide field effect transistors by dielectrophoresis

    International Nuclear Information System (INIS)

    Joung, Daeha; Chunder, A; Zhai, Lei; Khondaker, Saiful I

    2010-01-01

    We demonstrate high yield fabrication of field effect transistors (FET) using chemically reduced graphene oxide (RGO) sheets. The RGO sheets suspended in water were assembled between prefabricated gold source and drain electrodes using ac dielectrophoresis. With the application of a backgate voltage, 60% of the devices showed p-type FET behavior, while the remaining 40% showed ambipolar behavior. After mild thermal annealing at 200 deg. C, all ambipolar RGO FET remained ambipolar with increased hole and electron mobility, while 60% of the p-type RGO devices were transformed to ambipolar. The maximum hole and electron mobilities of the devices were 4.0 and 1.5 cm 2 V -1 s -1 respectively. High yield assembly of chemically derived RGO FET will have significant impact in scaled up fabrication of graphene based nanoelectronic devices.

  11. Meeting the global food demand of the future by engineering crop photosynthesis and yield potential.

    Science.gov (United States)

    Long, Stephen P; Marshall-Colon, Amy; Zhu, Xin-Guang

    2015-03-26

    Increase in demand for our primary foodstuffs is outstripping increase in yields, an expanding gap that indicates large potential food shortages by mid-century. This comes at a time when yield improvements are slowing or stagnating as the approaches of the Green Revolution reach their biological limits. Photosynthesis, which has been improved little in crops and falls far short of its biological limit, emerges as the key remaining route to increase the genetic yield potential of our major crops. Thus, there is a timely need to accelerate our understanding of the photosynthetic process in crops to allow informed and guided improvements via in-silico-assisted genetic engineering. Potential and emerging approaches to improving crop photosynthetic efficiency are discussed, and the new tools needed to realize these changes are presented. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. An investigation of oxidation products and SOA yields from OH + pesticide reactions

    Science.gov (United States)

    Murschell, T.; Friedman, B.; Link, M.; Farmer, D.

    2016-12-01

    Pesticides are used globally in agricultural and residential areas. After application and/or volatilization from a surface, these compounds can be transported over long distances in the atmosphere. However, their chemical fate, including oxidation and gas-particle partitioning in the atmosphere, is not well understood. We present gas and particle measurements of oxidation products from pesticide + OH reactions using a dynamic solution injection system coupled to an Oxidative Flow Reactor. Products were detected with a High Resolution Time of Flight Iodide Chemical Mass Spectrometer (HR-ToF-CIMS) and a Size Mobility Particle Scanner (SMPS). The OFR allows pesticides to react with variable OH radical exposures, ranging from the equivalent of one day to a full week of atmospheric oxidative aging. In this work, we explore pesticide oxidation products from reaction with OH and ozone, and compare those products to photolysis reactions. Pesticides of similar chemical structures were explored, including acetochlor / metolachlor and permethrin / cypermethrin, to explore mechanistic differences. We present chemical parameters including average product oxidation state, average oxygen to carbon ratio, and potential secondary organic aerosol formation for each of these compounds.

  13. Potential yields of wells in unconsolidated aquifers in upstate New York--Hudson-Mohawk sheet

    Science.gov (United States)

    Bugliosi, Edward F.; Trudell, Ruth A.; Casey, George D.

    1988-01-01

    This map shows the location and potential well yields of unconsolidated aquifers in the Hudson-Mohawk region at a scale of 1:250,000. It also delineates segments of aquifers that are heavily used by community water systems and designated by the New York State Department of Environmental Conservation as ' Primary Water Supply ' aquifers, and cites published reports that give detailed information on each area. Most aquifers were deposited in low-lying areas such as valleys or plains during deglaciations of the region. Thick, permeable, well-sorted sand and gravel deposits generally yield large quantities of water, greater than 100 gal/min. Thin sand, sand and gravel deposits, or thicker gravel units that have a large content of silt and fine sand, yield moderate amounts of water, 10 to 100 gal/min. Wells dug in till and those drilled in bedrock commonly yield less than 10 gal/min. (USGS)

  14. Potential yields of wells in unconsolidated aquifers in upstate New York--lower Hudson sheet

    Science.gov (United States)

    Bugliosi, Edward F.; Trudell, Ruth A.

    1988-01-01

    This map shows the location and potential well yields from unconsolidated aquifers in the lower-Hudson region at a 1:250 ,000 scale. It also delineates segments of aquifers that are heavily used by community water systems and designated by the New York State Department of Environmental Conservation as ' Primary water supply ' aquifers and cites published reports that give detailed information on each area. Most aquifers were deposited in low-lying areas such as valleys or plains during deglaciation of the region. Thick, permeable, well-sorted sand and gravel deposits generally yield large quantities of water, more than 100 gal/min. Thin sand, sand and gravel deposits, or thicker gravel units that have a large content of silt and fine sand, yield moderate amounts of water, 10 to 100 gal/min. Wells dug in till and those drilled in bedrock commonly yield less than 10 gal/min. (USGS)

  15. Potential yields of wells in unconsolidated aquifers in upstate New York-- Adirondack sheet

    Science.gov (United States)

    Bugliosi, Edward F.; Trudell, Ruth A.; Casey, George D.

    1988-01-01

    This map shows the location and potential well yield from unconsolidated aquifers in the Adirondack region at a 1:250,000 scale. It also delineates segments of aquifers that are heavily used by community water systems and designated by the New York State Department of Environmental Conservation as ' Primary Water Supply ' aquifers and cites published reports that give detailed information on each area. Most aquifers were deposited in low-lying areas such as valleys or plains during deglaciation of the region. Thick, permeable, well-sorted sand and gravel deposits generally yield large quantities of water, greater than 100 gal/min. Thin sand, sand and gravel deposits, or thicker gravel units have a large content of silt and fine sand, yield moderate amounts of water, 10 to 100 gal/min. Wells dug in till and those drilled in bedrock commonly yield less than 10 gal/min. (USGS)

  16. Stability of rust resistance and yield potential of some icarda bread wheat lines in Pakistan

    International Nuclear Information System (INIS)

    Shah, S.J.A.; Khan, A.J.; Azam, F.; Mirza, J.I.; Atiq-ur-Rehman

    2003-01-01

    Thirty bread wheat lines resistant to Yellow rust (Yr) were selected after careful screening from two ICARDA nurseries during 1998 - 1999, Rabi season at Nuclear Institute for Food and Agriculture (NIFA), Tarnab, Peshawar under severe disease pressure. In the following crop cycle, these selections were again field evaluated for stability and effectiveness of Yr resistance at multilocations while their yield potential was ascertained at Tarnab in two different trials with Tatara as commercial check. Results revealed that uniformity was found in the potential behavior of 23 lines (77%) in both the cropping seasons against Yr. This included some high yielding (up to 7067 kg/ ha) and low yielding lines (up to 4333 kg / ha) when compared with the check (6089 kg / ha). Yield potential of some high yielding lines with stable Yr resistance should be further evaluated over sites and seasons for wide adaptability, under national uniform testing in order to select and deploy future varieties to combat Yr for acquiring food security in Pakistan.(author)

  17. Predicting spring barley yield from variety-specific yield potential, disease resistance and straw length, and from environment-specific disease loads and weed pressure

    DEFF Research Database (Denmark)

    Østergård, Hanne; Kristensen, Kristian; Pinnschmidt, Hans O.

    2008-01-01

    For low-input crop production, well-characterised varieties increase the possibilities of managing diseases and weeds. This analysis aims at developing a framework for analyzing grain yield using external varietal information about disease resistance, weed competitiveness and yield potential and ...... growth habit. Higher grain yield was thus predicted for taller plants under weed pressure. The results are discussed in relation to the model framework, impact of the considered traits and use of information from conventional variety testing in organic cropping systems....

  18. Potentials of flora species on the yield of honey in Dakka Forest ...

    African Journals Online (AJOL)

    The study assessed the potentials of flora on the yield of honey in Bali Local Government Area of Taraba State. Floral resources that could accommodate possible apicultural industry have not been examined in the study area. Data on plant species (trees, shrubs and herbaceous plants) utilized by honeybees were obtained ...

  19. Triplet-State Dissolved Organic Matter Quantum Yields and Lifetimes from Direct Observation of Aromatic Amine Oxidation.

    Science.gov (United States)

    Schmitt, Markus; Erickson, Paul R; McNeill, Kristopher

    2017-11-21

    Excited triplet state chromophoric dissolved organic matter ( 3 CDOM*) is a short-lived mixture of excited-state species that plays important roles in aquatic photochemical processes. Unlike the study of the triplet states of well-defined molecules, which are amenable to transient absorbance spectroscopy, the study of 3 CDOM* is hampered by it being a complex mixture and its low average intersystem crossing quantum yield (Φ ISC ). This study is an alternative approach to investigating 3 CDOM* using transient absorption laser spectroscopy. The radical cation of N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD), formed through oxidation by 3 CDOM*, was directly observable by transient absorption spectroscopy and was used to probe basic photophysical properties of 3 CDOM*. Quenching and control experiments verified that TMPD •+ was formed from 3 CDOM* under anoxic conditions. Model triplet sensitizers with a wide range of excited triplet state reduction potentials and CDOM oxidized TMPD at near diffusion-controlled rates. This gives support to the idea that a large cross-section of 3 CDOM* moieties are able to oxidize TMPD and that the complex mixture of 3 CDOM* can be simplified to a single signal. Using the TMPD •+ transient, the natural triplet lifetime and Φ ISC for different DOM isolates and natural waters were quantified; values ranged from 12 to 26 μs and 4.1-7.8%, respectively.

  20. Influence of oxidative stress and grains on sclerotial biomass and carotenoid yield of Penicillium sp. PT95.

    Science.gov (United States)

    Chen, Shu-Jun; Wang, Qi; Han, Jian-Rong

    2010-08-01

    Oxidative stress and grains were evaluated for carotenoid production by solid-state fermentation using Penicillium sp. PT95. When the fungus was grown at high oxidative stress, its sclerotial biomass and carotenoid content in sclerotia increased significantly with respect to low oxidative stress (P < 0.01). High oxidative stress also caused a statistically significant increase in carotenoid yield as compared with low oxidative stress (P < 0.01). Both the sclerotial biomass and the amount of carotenoid accumulated in sclerotia of strain PT95 were strongly dependent on the grain medium used. Among the grain media tested under high oxidative stress, buckwheat medium gave the highest content of carotenoid in sclerotia (828 microg/g dry sclerotia), millet medium gave respectively the highest sclerotial biomass (12.69 g/100 g grain) and carotenoid yield (10.152 mg/100 g grain). Copyright 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

  1. Electrochemical Oxidation by Square-Wave Potential Pulses in the Imitation of Oxidative Drug Metabolism

    NARCIS (Netherlands)

    Nouri-Nigjeh, Eslam; Permentier, Hjalmar P.; Bischoff, Rainer; Bruins, Andries P.

    2011-01-01

    Electrochemistry combined with mass spectrometry (EC-MS) is an emerging analytical technique in the imitation of oxidative drug metabolism at the early stages of new drug development. Here, we present the benefits of electrochemical oxidation by square-wave potential pulses for the oxidation of

  2. Economics and yields of energy plantations: Status and potential, 1992-1993 update

    International Nuclear Information System (INIS)

    Gambles, R.L.; Kenney, W.A.

    1994-01-01

    An update is presented of a study carried out to: determine the factors affecting the cost of energy conversion feedstocks in short rotation intensive culture plantations of trees; determine the factors influencing biomass yield; identify interrelationships between the previous two objectives; present estimates of potential biomass yields and associated economics; and to identify gaps in the knowledge of the economics and yields of biomass production and their interrelationships. Developments in economics and yields in short rotation intensive silviculture for the production of biomass energy since 1991 are documented. The most substantial changes have been: the introduction of new clones in Sweden with a 20% increase in yield; illustrating the potential genetic gains achievable through selection and breeding; and halving of harvesting costs with new machinery. Harvesting costs with chipping incorporated have fallen to $51.21/dry tonne. The twin row ESM and Frobbester harvesters have lower estimated costs of $36.62 and $ 33.69 respectively. Agricultural based machines have further reduced costs to $19.42 and $26.12/dry tonne. Using these new data, three new scenarios were developed for cost of production analysis, using contract labour, farm labour or farm labour plus a subsidy. A contracted operation is now viable with an annual equivalent net value (AENV) of $35/ha. With the use of farm labour for most operations and omitting land rent, profitability increased to $127/ha. With a subsidy of $75/ha, the AENV increases to $205/ha. 25 refs., 1 fig., 3 tabs

  3. The potential of satellite-observed crop phenology to enhance yield gap assessments in smallholder landscapes

    Directory of Open Access Journals (Sweden)

    John M A Duncan

    2015-08-01

    Full Text Available Many of the undernourished people on the planet obtain their entitlements to food via agricultural-based livelihood strategies, often on underperforming croplands and smallholdings. In this context, expanding cropland extent is not a viable strategy for smallholders to meet their food needs. Therefore, attention must shift to increasing productivity on existing plots and ensuring yield gaps do not widen. Thus, supporting smallholder farmers to sustainably increase the productivity of their lands is one part of a complex solution to realising universal food security. However, the information (e.g. location and causes of cropland underperformance required to support measures to close yield gaps in smallholder landscapes are often not available. This paper reviews the potential of crop phenology, observed from satellites carrying remote sensing sensors, to fill this information gap. It is suggested that on a theoretical level phenological approaches can reveal greater intra-cropland thematic detail, and increase the accuracy of crop extent maps and crop yield estimates. However, on a practical level the spatial mismatch between the resolution at which crop phenology can be estimated from satellite remote sensing data and the scale of yield variability in smallholder croplands inhibits its use in this context. Similarly, the spatial coverage of remote sensing-derived phenology offers potential for integration with ancillary spatial datasets to identify causes of yield gaps. To reflect the complexity of smallholder cropping systems requires ancillary datasets at fine spatial resolutions which, often, are not available. This further precludes the use of crop phenology in attempts to unpick the causes of yield gaps. Research agendas should focus on generating fine spatial resolution crop phenology, either via data fusion or through new sensors (e.g. Sentinel-2 in smallholder croplands. This has potential to transform the applied use of remote sensing

  4. Simulating potential growth and yield of oil palm (Elaeis guineensis) with PALMSIM: Model description, evaluation and application

    NARCIS (Netherlands)

    Hoffmann, M.; Castaneda Vera, A.; Wijk, van M.T.; Giller, K.E.; Oberthür, T.; Donough, C.; Whitbread, A.M.

    2014-01-01

    Reducing the gap between water-limited potential yield and actual yield in oil palm production systems through intensification is seen as an important option for sustainably increasing palm oil production. Simulation models can play an important role in quantifying water-limited potential yield, and

  5. Study on uranium metallization yield of spent Pressurized Water Reactor fuels and oxidation behavior of fission products in uranium metals

    International Nuclear Information System (INIS)

    Choi, Ke Chon; Lee, Chang Heon; Kim, Won Ho

    2003-01-01

    Metallization yield of uranium oxide to uranium metal from lithium reduction process of spent Pressurized Water Reactor (PWR) fuels was measured using thermogravimetric analyzer. A reduced metal produced in the process was divided into a solid and a powder part, and each metallization yield was measured. Metallization yield of the solid part was 90.7∼95.9 wt%, and the powder being 77.8∼71.5 wt% individually. Oxidation behaviour of the quarternary alloy was investigated to take data on the thermal oxidation stability necessary for the study on dry storage of the reduced metal. At 600∼700 .deg. C, weight increments of allow of No, Ru, Rh and Pd was 0.40∼0.55 wt%. Phase change on the surface of the allow was started at 750 .deg. C. In particular, Mo was rapidly oxidized and then the alloy lost 0.76∼25.22 wt% in weight

  6. Simulating the potential yield and yield gaps of sugar beet due to water and nitrogen limitations in Khorasan province using SUCROS model

    Directory of Open Access Journals (Sweden)

    R Deihimfard

    2015-12-01

    Full Text Available Introduction Crop productivity is highly constrained by water and nitrogen limitations in many areas of the world (Kalra et al., 2007. Therefore, there is a need to investigate more on nitrogen and water management to achieve higher production as well as quality. Irrigated sugar beet in the cropping systems of Khorasan province in northeastern of Iran accounts for about 34% of the land area under sugar beet production (~115,000 ha with an average yield of around 36 t.ha-1 (Anonymous, 2009. However, there is a huge yield gap (the difference between potential and water and nitrogen-limited yield mainly due to biotic and abiotic factors causing major reduction in farmers’ yield. Accordingly, yield gap analysis should be carried out to reduce the yield reduction and reach the farmer’s yield to the potential yield. The current study aimed to simulate potential yield as well as yield gap related to water and nitrogen shortage in the major sugar beet-growing areas of Khorasan province of Iran. Materials and methods This study was carried out in 6 locations across Khorasan province, which is located in the northeast of Iran. Long term weather data for 1986 to 2009 were obtained from Iran Meteorological Organization for 6 selected locations. The weather data included daily sunshine hours (h, daily maximum and minimum temperatures (◦C, and daily rainfall (mm. Daily solar radiation was estimated using the Goudriaan (1993 method. The validated SUCROSBEET model (Deihimfard, 2011; Deihimfard et al., 2011 was then used to estimate potential, water and nitrogen-limited yield and yield gap of sugar beet for 6 selected locations across the Khorasan province in the northeast of Iran. This model simulates the impacts of weather, genotype and management factors on crop growth and development, soil water and nitrogen balance on a daily basis and finally it predicts crop yield. The model requires input data, including local weather and soil conditions, cultivar

  7. Estimating national crop yield potential and the relevance of weather data sources

    Science.gov (United States)

    Van Wart, Justin

    2011-12-01

    To determine where, when, and how to increase yields, researchers often analyze the yield gap (Yg), the difference between actual current farm yields and crop yield potential. Crop yield potential (Yp) is the yield of a crop cultivar grown under specific management limited only by temperature and solar radiation and also by precipitation for water limited yield potential (Yw). Yp and Yw are critical components of Yg estimations, but are very difficult to quantify, especially at larger scales because management data and especially daily weather data are scarce. A protocol was developed to estimate Yp and Yw at national scales using site-specific weather, soils and management data. Protocol procedures and inputs were evaluated to determine how to improve accuracy of Yp, Yw and Yg estimates. The protocol was also used to evaluate raw, site-specific and gridded weather database sources for use in simulations of Yp or Yw. The protocol was applied to estimate crop Yp in US irrigated maize and Chinese irrigated rice and Yw in US rainfed maize and German rainfed wheat. These crops and countries account for >20% of global cereal production. The results have significant implications for past and future studies of Yp, Yw and Yg. Accuracy of national long-term average Yp and Yw estimates was significantly improved if (i) > 7 years of simulations were performed for irrigated and > 15 years for rainfed sites, (ii) > 40% of nationally harvested area was within 100 km of all simulation sites, (iii) observed weather data coupled with satellite derived solar radiation data were used in simulations, and (iv) planting and harvesting dates were specified within +/- 7 days of farmers actual practices. These are much higher standards than have been applied in national estimates of Yp and Yw and this protocol is a substantial step in making such estimates more transparent, robust, and straightforward. Finally, this protocol may be a useful tool for understanding yield trends and directing

  8. Potential limitations for potato yields in raised soil field systems near Lake Titicaca

    Directory of Open Access Journals (Sweden)

    Lozada Diego Sánchez de

    2006-01-01

    Full Text Available During the last two decades, various non-governmental organizations have strongly encouraged Bolivian farmers in the Altiplano region near Lake Titicaca to resume the ancestral agricultural practice of constructing raised fields. In addition to improved drainage and possibilities this practice affords for sub-irrigation, advocated benefits of this system traditionally include frost mitigation and high crop yields. Until recently, reliable data to assess the extent of these benefits were unfortunately lacking. In this context, field experiments on raised fields were designed and carried out at two locations in the Bolivian Altiplano to obtain reliable potato yield and temperature data. Observed yields ranged from 2.73 to 10.80 t ha-1 at the first site, where salinity caused significant yield variability (R² = 0.79. At the second site, yields per raised platform varied between 8.25 and 33.45 t ha-1. However, comparable yields were obtained in flat control plots in spite of a mid-season frost, and the minimum temperatures differed only by 1ºC in the conventional plots relative to the raised fields. These results suggest that, under the experimental conditions, the potential benefits of raised fields in terms of frost mitigation or increased yields might only be observable in exceptionally bad years, when extreme frosts wipe out entire potato crops on conventional fields. Nevertheless, it is argued that in spite of these marginally supportive observations, raised-field agriculture may still be a viable option for farmers to consider if the water-filled channels between the raised fields are managed for fish and fertilizer production.

  9. Yield optimization in a cycled trickle-bed reactor: ethanol catalytic oxidation as a case study

    Energy Technology Data Exchange (ETDEWEB)

    Ayude, A.; Haure, P. [INTEMA, CONICET, Mar del Plata (Argentina); Cassanello, M. [Universidad de Buenos Aires, PINMATE, Departamento de Industrias, FCEyN, Buenos Aires (Argentina); Martinez, O. [Departamento de Ingenieria Quimica, FI-UNLP-CINDECA, La Plata (Argentina)

    2012-05-15

    The effect of slow ON-OFF liquid flow modulation on the yield of consecutive reactions is investigated for oxidation of aqueous ethanol solutions using a 0.5 % Pd/Al{sub 2}O{sub 3} commercial catalyst in a laboratory trickle-bed reactor. Experiments with modulated liquid flow rate (MLFR) were performed under the same hydrodynamic conditions (degree of wetting, liquid holdup) as experiments with constant liquid flow rate (CLFR). Thus, the impact of the duration of wet and dry cycles as well as the period can be independently investigated. Depending on cycling conditions, acetaldehyde or acetic acid production is favored with MLFR compared to CLFR. Results suggest both the opportunity and challenge of finding a way to tune the cycling parameters for producing the most appropriate product. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Improving yield potential in crops under elevated CO(2): Integrating the photosynthetic and nitrogen utilization efficiencies.

    Science.gov (United States)

    Kant, Surya; Seneweera, Saman; Rodin, Joakim; Materne, Michael; Burch, David; Rothstein, Steven J; Spangenberg, German

    2012-01-01

    Increasing crop productivity to meet burgeoning human food demand is challenging under changing environmental conditions. Since industrial revolution atmospheric CO(2) levels have linearly increased. Developing crop varieties with increased utilization of CO(2) for photosynthesis is an urgent requirement to cope with the irreversible rise of atmospheric CO(2) and achieve higher food production. The primary effects of elevated CO(2) levels in most crop plants, particularly C(3) plants, include increased biomass accumulation, although initial stimulation of net photosynthesis rate is only temporal and plants fail to sustain the maximal stimulation, a phenomenon known as photosynthesis acclimation. Despite this acclimation, grain yield is known to marginally increase under elevated CO(2). The yield potential of C(3) crops is limited by their capacity to exploit sufficient carbon. The "C fertilization" through elevated CO(2) levels could potentially be used for substantial yield increase. Rubisco is the rate-limiting enzyme in photosynthesis and its activity is largely affected by atmospheric CO(2) and nitrogen availability. In addition, maintenance of the C/N ratio is pivotal for various growth and development processes in plants governing yield and seed quality. For maximizing the benefits of elevated CO(2), raising plant nitrogen pools will be necessary as part of maintaining an optimal C/N balance. In this review, we discuss potential causes for the stagnation in yield increases under elevated CO(2) levels and explore possibilities to overcome this limitation by improved photosynthetic capacity and enhanced nitrogen use efficiency. Opportunities of engineering nitrogen uptake, assimilatory, and responsive genes are also discussed that could ensure optimal nitrogen allocation toward expanding source and sink tissues. This might avert photosynthetic acclimation partially or completely and drive for improved crop production under elevated CO(2) levels.

  11. Improving yield potential in crops under elevated CO2: Integrating the photosynthetic and nitrogen utilization efficiencies

    Science.gov (United States)

    Kant, Surya; Seneweera, Saman; Rodin, Joakim; Materne, Michael; Burch, David; Rothstein, Steven J.; Spangenberg, German

    2012-01-01

    Increasing crop productivity to meet burgeoning human food demand is challenging under changing environmental conditions. Since industrial revolution atmospheric CO2 levels have linearly increased. Developing crop varieties with increased utilization of CO2 for photosynthesis is an urgent requirement to cope with the irreversible rise of atmospheric CO2 and achieve higher food production. The primary effects of elevated CO2 levels in most crop plants, particularly C3 plants, include increased biomass accumulation, although initial stimulation of net photosynthesis rate is only temporal and plants fail to sustain the maximal stimulation, a phenomenon known as photosynthesis acclimation. Despite this acclimation, grain yield is known to marginally increase under elevated CO2. The yield potential of C3 crops is limited by their capacity to exploit sufficient carbon. The “C fertilization” through elevated CO2 levels could potentially be used for substantial yield increase. Rubisco is the rate-limiting enzyme in photosynthesis and its activity is largely affected by atmospheric CO2 and nitrogen availability. In addition, maintenance of the C/N ratio is pivotal for various growth and development processes in plants governing yield and seed quality. For maximizing the benefits of elevated CO2, raising plant nitrogen pools will be necessary as part of maintaining an optimal C/N balance. In this review, we discuss potential causes for the stagnation in yield increases under elevated CO2 levels and explore possibilities to overcome this limitation by improved photosynthetic capacity and enhanced nitrogen use efficiency. Opportunities of engineering nitrogen uptake, assimilatory, and responsive genes are also discussed that could ensure optimal nitrogen allocation toward expanding source and sink tissues. This might avert photosynthetic acclimation partially or completely and drive for improved crop production under elevated CO2 levels. PMID:22833749

  12. Ethanol yield and energy potential of stems from a spectrum of sorghum biomass types

    Energy Technology Data Exchange (ETDEWEB)

    McBee, G.G.; Creelman, R.A.; Miller, F.R.

    1988-01-01

    Sorghum biomass is a renewable resource that offers significant potential for energy utilization. Six sorghum cultivars, representing an array of stem types, were evaluated for ethanol yield. Ethanol production was individually obtained for both the total stem and the pith of each type by anaerobic yeast fermentation. Value of the energy contained in the rind was determined by calorimetry. The highest yield of ethanol from total stem fermentation was 3418.3 liters ha/sup -1/ produced from Rio. Fermentation of Rio pith to ethanol and combustion of the rind resulted in the highest total energy value of the cultivars. The least and greatest energy values were 6.3 and 44.3 x 10/sup 6/ kcal ha/sup -1/ for SC0056-14 and Rio, respectively. Conversion ratios of potentially fermentable carbohydrates (within the vegetative biomass) to ethanol produced, averaged 0.438 for the pith and 0.406 for total stems.

  13. Rosemary Aromatization of Extra Virgin Olive Oil and Process Optimization Including Antioxidant Potential and Yield

    Directory of Open Access Journals (Sweden)

    Erkan Karacabey

    2016-08-01

    Full Text Available Aromatization of olive oil especially by spices and herbs has been widely used technique throughout the ages in Mediterranean diets. The present study was focused on aromatization of olive oil by rosemary (Rosmarinus officinalis L.. Aromatization process was optimized by response surface methodology as a function of malaxation’s conditions (temperature and time. According to authors’ best knowledge it was first time for examination of oil yield performance with antioxidant potential and pigments under effect of aromatization parameters. For all oil samples, values of the free acidity, peroxide, K232 and K270 as quality parameters fell within the ranges established for the highest quality category “extra virgin oil”. Oil yield (mL oil/kg olive paste changed from 158 to 208 with respect to design parameters. Total phenolic content and free radical scavenging activity as antioxidant potential of olive oil samples were varied in the range of 182.44 – 348.65 mg gallic acid equivalent/kg oil and 28.91 – 88.75 % inhibition of 2,2-Diphenyl-1-picrylhydrazyl-(DPPH•, respectively. Total contents of carotenoid, chlorophyll and pheophytin a as pigments in oil samples were found to be in between 0.09 – 0.48 mg carotenoid/kg oil, 0.11 – 0.96 mg chlorophyll/kg oil, 0.15 – 4.44 mg pheo α/kg oil, respectively. The proposed models for yield, pigments and antioxidant potential responses were found to be good enough for successful prediction of experimental results. Total phenolics, carotenoids and free radical scavenging activity of aromatized olive oil and oil yield were maximized to gather and optimal conditions were determined as 25°C, 84 min, and 2 % (Rosemary/olive paste; w/w.

  14. Yield potential of a radiation induced early-dwarf mutant in linseed

    International Nuclear Information System (INIS)

    Nayar, G.G.

    1975-01-01

    An early maturing dwarf mutant, TL-1 was isolated in the high yielding linseed (Linum usitatissimum L.) wariety Neelum following seed irradiation with 50 kR gamma rays. The yield components of the mutant have been evaluated for its productivity in the M 7 generation. TL-1 is compact and significantly short in height (41.8 +- 2.71 cm) as compared to Neelum (79.2 +- 3.08 cm). In flowering the mutant is 30 days earlier than the parent under Trombay conditions. TL-1 and Neelum did not differ significantly in their mean number of primary branches. Although the mean seed yield per plant is lower, in 1000 seed weight the mutant is markedly superior to the parent. The oil content in TL-1 is significantly higher by 3.5 percent points than Neelum and its oil is lighter in colour. By growing more plants per unit area with reduced spacing, the yield potential of TL-1 was considerably increased. The productivity of oil per hectare per day of TL-1 was higher than Neelum. (author)

  15. Potential impacts of agricultural drought on crop yield variability under a changing climate in Texas

    Science.gov (United States)

    Lee, K.; Leng, G.; Huang, M.; Sheffield, J.; Zhao, G.; Gao, H.

    2017-12-01

    Texas has the largest farm area in the U.S, and its revenue from crop production ranks third overall. With the changing climate, hydrological extremes such as droughts are becoming more frequent and intensified, causing significant yield reduction in rainfed agricultural systems. The objective of this study is to investigate the potential impacts of agricultural drought on crop yields (corn, sorghum, and wheat) under a changing climate in Texas. The Variable Infiltration Capacity (VIC) model, which is calibrated and validated over 10 major Texas river basins during the historical period, is employed in this study.The model is forced by a set of statistically downscaled climate projections from Coupled Model Intercomparison Project Phase 5 (CMIP5) model ensembles at a spatial resolution of 1/8°. The CMIP5 projections contain four Representative Concentration Pathways (RCP) that represent different greenhouse gas concentration (4.5 and 8.5 w/m2 are selected in this study). To carry out the analysis, VIC simulations from 1950 to 2099 are first analyzed to investigate how the frequency and severity of agricultural droughts will be altered in Texas (under a changing climate). Second, future crop yields are projected using a statistical crop model. Third, the effects of agricultural drought on crop yields are quantitatively analyzed. The results are expected to contribute to future water resources planning, with a goal of mitigating the negative impacts of future droughts on agricultural production in Texas.

  16. Monoterpene oxidation in an oxidative flow reactor: SOA yields and the relationship between bulk gas-phase properties and organic aerosol growth

    Science.gov (United States)

    Friedman, B.; Link, M.; Farmer, D.

    2016-12-01

    We use an oxidative flow reactor (OFR) to determine the secondary organic aerosol (SOA) yields of five monoterpenes (alpha-pinene, beta-pinene, limonene, sabinene, and terpinolene) at a range of OH exposures. These OH exposures correspond to aging timescales of a few hours to seven days. We further determine how SOA yields of beta-pinene and alpha-pinene vary as a function of seed particle type (organic vs. inorganic) and seed particle mass concentration. We hypothesize that the monoterpene structure largely accounts for the observed variance in SOA yields for the different monoterpenes. We also use high-resolution time-of-flight chemical ionization mass spectrometry to calculate the bulk gas-phase properties (O:C and H:C) of the monoterpene oxidation systems as a function of oxidant concentrations. Bulk gas-phase properties can be compared to the SOA yields to assess the capability of the precursor gas-phase species to inform the SOA yields of each monoterpene oxidation system. We find that the extent of oxygenated precursor gas-phase species corresponds to SOA yield.

  17. The Effects of Drought Stress on Yield, Yield Components and Anti-oxidant of Two Garlic (Allium sativum L. Ecotypes with Different Planting Densities

    Directory of Open Access Journals (Sweden)

    shiva akbari

    2016-07-01

    Full Text Available Introduction Drought stress reduces plant growth by affecting various physiological and biochemical processes, such as photosynthesis, respiration, translocation, ion uptake, carbohydrates, nutrient metabolism and growth promoters. Garlic (Allium sativum L. is an annual bulb crop that has been cultivated since ancient times and was used as a spice and condiment for many centuries. Garlic is an important plant because of its pharmaceutical properties. The optimum yield of this bulb crop depends on well-managed irrigation, fertilization and cultivation practices. In the final and middle stages of growth, garlic is sensitive to water stress and low irrigation is unsuitable in these stages. This experiment was established to study the influence of drought stress and planting density on yield and its components and the non-enzymatic anti-oxidant content of two different garlic ecotypes. Materials and methods This study was conducted in 2011-2012 in a farmland at the south east of Semnan city. The experimental layout was a split-plot factorial with a randomized complete block design with three replications. The treatments were comprised of three factors: irrigation rates (60%, 80% and 100% of estimated crop evapotranspiration (ETC as the main plot and the factorial combination of three levels of planting density (30, 40 and 50 plants.m-2 and two ecotypes (Tabas and Toroud as the sub-plots. To estimate the crop water requirement, different meteorological parameters were collected from Semnan weather station and were used based on FAO-56 water irrigation calculation instructions. After harvesting, ten garlic plants were sampled randomly in each plot and bulb yield components were measured. To calculate the leaves anti-oxidant content, DPPH method was used. The statistical significances of mean values were assessed by analysis of variance and LSD tests at p≤0.05. All calculations were performed using SAS and Mstat-C softwares. Results and discussion

  18. Yield Potential of Ten Peanut Introgression Lines derived from Crosses between Arachis cardenassii and A. hypogaea

    Directory of Open Access Journals (Sweden)

    AHMAD RIDUAN

    2005-09-01

    Full Text Available Diploid species of peanut (Arachis cardenasii showed no symptoms of PStV infection when mechanically inoculated with PStV. Some introgression lines derived from A. cardenasii and A. hypogaea hybridization have been introduced to Indonesia. Evaluation of their adaptability and yield potential were necessary before pursuing further utilization of these introgression lines. The objectives of this research were to determine yield potential of the introgression lines of peanut in green house and field conditions and to evaluate incidence of PStV infection in the field. Peanut plants were grown in the green house and in the field according to standard procedures for raising peanut. Results of the experiments showed that growth and developmental characters of the tested lines were similar between field and green house grown plants. The introgression lines generally exhibited higher secondary branches and longer to flower and harvest as compared to peanut cv. Gajah and Kelinci. The NC-CS30 line was identfied as having higher yield and bigger seed size as compared to standard peanut cultivars (Gajah and Kelinci. Therefore, NC-CS30 germplasm may be further developed as commercial peanut cultivar or be used as donor for peanut breeding in Indonesia.

  19. Effect of oxidant concentration, exposure time, and seed particles on secondary organic aerosol chemical composition and yield

    Directory of Open Access Journals (Sweden)

    A. T. Lambe

    2015-03-01

    This similarity in turn suggests that both in the flow reactor and in chambers, SOA chemical composition at low OH exposure is governed primarily by gas-phase OH oxidation of the precursors rather than heterogeneous oxidation of the condensed particles. In general, SOA yields measured in the flow reactor are lower than measured in chambers for the range of equivalent OH exposures that can be measured in both the flow reactor and chambers. The influence of sulfate seed particles on isoprene SOA yield measurements was examined in the flow reactor. The studies show that seed particles increase the yield of SOA produced in flow reactors by a factor of 3 to 5 and may also account in part for higher SOA yields obtained in the chambers, where seed particles are routinely used.

  20. Modeling the yield potential of dryland canola under current and future climates in California

    Science.gov (United States)

    George, N.; Kaffka, S.; Beeck, C.; Bucaram, S.; Zhang, J.

    2012-12-01

    Models predict that the climate of California will become hotter, drier and more variable under future climate change scenarios. This will lead to both increased irrigation demand and reduced irrigation water availability. In addition, it is predicted that most common Californian crops will suffer a concomitant decline in productivity. To remain productive and economically viable, future agricultural systems will need to have greater water use efficiency, tolerance of high temperatures, and tolerance of more erratic temperature and rainfall patterns. Canola (Brassica napus) is the third most important oilseed globally, supporting large and well-established agricultural industries in Canada, Europe and Australia. It is an agronomically useful and economically valuable crop, with multiple end markets, that can be grown in California as a dryland winter rotation with little to no irrigation demand. This gives canola great potential as a new crop for Californian farmers both now and as the climate changes. Given practical and financial limitations it is not always possible to immediately or widely evaluate a crop in a new region. Crop production models are therefore valuable tools for assessing the potential of new crops, better targeting further field research, and refining research questions. APSIM is a modular modeling framework developed by the Agricultural Production Systems Research Unit in Australia, it combines biophysical and management modules to simulate cropping systems. This study was undertaken to examine the yield potential of Australian canola varieties having different water requirements and maturity classes in California using APSIM. The objective of the work was to identify the agricultural regions of California most ideally suited to the production of Australian cultivars of canola and to simulate the production of canola in these regions to estimate yield-potential. This will establish whether the introduction and in-field evaluation of better

  1. Lipids of Rhodotorula mucilaginosa IIPL32 with biodiesel potential: Oil yield, fatty acid profile, fuel properties.

    Science.gov (United States)

    Khot, Mahesh; Ghosh, Debashish

    2017-04-01

    This study analyzes the single cell oil (SCO), fatty acid profile, and biodiesel fuel properties of the yeast Rhodotorula mucilaginosa IIPL32 grown on the pentose fraction of acid pre-treated sugarcane bagasse as a carbon source. The yeast biomass from nitrogen limiting culture conditions (15.3 g L -1 ) was able to give the SCO yield of 0.17 g g -1 of xylose consumed. Acid digestion, cryo-pulverization, direct in situ transesterification, and microwave assisted techniques were evaluated in comparison to the Soxhlet extraction for the total intracellular yeast lipid recovery. The significant differences were observed among the SCO yield of different methods and the in situ transesterification stood out most for effective yeast lipid recovery generating 97.23 mg lipid as FAME per gram dry biomass. The method was fast and consumed lesser solvent with greater FAME yield while accessing most cellular fatty acids present. The yeast lipids showed the major presence of monounsaturated fatty esters (35-55%; 18:1, 16:1) suitable for better ignition quality, oxidative stability, and cold-flow properties of the biodiesel. Analyzed fuel properties (density, kinematic viscosity, cetane number) of the yeast oil were in good agreement with international biodiesel standards. The sugarcane bagasse-derived xylose and the consolidated comparative assessment of lab scale SCO recovery methods highlight the necessity for careful substrate choice and validation of analytical method in yeast oil research. The use of less toxic co-solvents together with solvent recovery and recycling would help improve process economics for sustainable production of biodiesel from the hemicellulosic fraction of cheap renewable sources. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Estimating the potential intensification of global grazing systems based on climate adjusted yield gap analysis

    Science.gov (United States)

    Sheehan, J. J.

    2016-12-01

    We report here a first-of-its-kind analysis of the potential for intensification of global grazing systems. Intensification is calculated using the statistical yield gap methodology developed previously by others (Mueller et al 2012 and Licker et al 2010) for global crop systems. Yield gaps are estimated by binning global pasture land area into 100 equal area sized bins of similar climate (defined by ranges of rainfall and growing degree days). Within each bin, grid cells of pastureland are ranked from lowest to highest productivity. The global intensification potential is defined as the sum of global production across all bins at a given percentile ranking (e.g. performance at the 90th percentile) divided by the total current global production. The previous yield gap studies focused on crop systems because productivity data on these systems is readily available. Nevertheless, global crop land represents only one-third of total global agricultural land, while pasture systems account for the remaining two-thirds. Thus, it is critical to conduct the same kind of analysis on what is the largest human use of land on the planet—pasture systems. In 2013, Herrero et al announced the completion of a geospatial data set that augmented the animal census data with data and modeling about production systems and overall food productivity (Herrero et al, PNAS 2013). With this data set, it is now possible to apply yield gap analysis to global pasture systems. We used the Herrero et al data set to evaluate yield gaps for meat and milk production from pasture based systems for cattle, sheep and goats. The figure included with this abstract shows the intensification potential for kcal per hectare per year of meat and milk from global cattle, sheep and goats as a function of increasing levels of performance. Performance is measured as the productivity achieved at a given ranked percentile within each bin.We find that if all pasture land were raised to their 90th percentile of

  3. Potential rates of ammonium oxidation, nitrite oxidation, nitrate reduction and denitrification in the young barley rhizosphere

    DEFF Research Database (Denmark)

    Højberg, Ole; Binnerup, S. J.; Sørensen, Jan

    1996-01-01

    Potential activities (enzyme contents) of ammonium (NH4+) oxidizing, nitrite (NO2-) oxidizing, nitrate (NO3-) reducing and denitrifying bacteria were measured in bulk and rhizosphere soil obtained from young barley plants in the field. The activities as well as pools of inorganic N (NH4+, NO2...

  4. Biomass yield potential of short-rotation hardwoods in the Great Plains

    Energy Technology Data Exchange (ETDEWEB)

    Geyer, W A [Kansas State Univ., Manhattan, KS (USA). Dept. of Forestry

    1989-01-01

    Wood for fuel has increased in importance. Its primary use in the world is for energy, increasingly coming from wood wastes and new biomass sources. One solution to the potential problem of using high-quality trees for fuel could be woody biomass grown under a short-rotation intensive culture system. Species, size, age and spacing are factors that affect biomass production of broadleafed trees. Trials of several species grown at close spacing (0.3 m x 0.3 m) and cut at various ages are described and related to the growth and yield of more conventionally spaced plantings on an alluvial site in eastern Kansas. (author).

  5. Disease Impact on Wheat Yield Potential and Prospects of Genetic Control

    DEFF Research Database (Denmark)

    Singh, Ravi P.; Singh, Pawan K.; Rutkoski, Jessica

    2016-01-01

    Wheat is grown worldwide in diverse geographical regions, environments, and production systems. Although many diseases and pests are known to reduce grain yield potential and quality, the three rusts and powdery mildew fungi have historically caused major crop losses and continue to remain...... economically important despite the widespread use of host resistance and fungicides. The evolution and fast spread of virulent and more aggressive race lineages of rust fungi have only worsened the situation. Fusarium head blight, leaf spotting diseases, and, more recently, wheat blast (in South America...... for most diseases; their selection through phenotyping reinforced with molecular strategies offers great promise in achieving more durable resistance and enhancing global wheat productivity....

  6. An analysis of the impact of native oxide, surface contamination and material density on total electron yield in the absence of surface charging effects

    Energy Technology Data Exchange (ETDEWEB)

    Iida, Susumu, E-mail: susumu.iida@toshiba.co.jp [EUVL Infrastructure Development Center, Inc., 16-1 Onogawa, Tsukuba-shi, Ibaraki-ken, 305-8569 (Japan); Ohya, Kaoru [Institute of Technology and Science, The University of Tokushima, 2-1 Minamijyousanjima-cho,Tokushima, 770-8506 (Japan); Hirano, Ryoichi; Watanabe, Hidehiro [EUVL Infrastructure Development Center, Inc., 16-1 Onogawa, Tsukuba-shi, Ibaraki-ken, 305-8569 (Japan)

    2016-10-30

    Highlights: • Total electron yields were assessed in the absence of any surface charging effect. • Experimental and simulation results showed a low native oxide energy barrier. • The yield enhancement effect of a native oxide layer was confirmed. • The yield enhancement effect of a thin surface contamination layer was confirmed. • Deviations in the material density from the theoretical values were evaluated. - Abstract: The effects of the presence of a native oxide film or surface contamination as well as variations in material density on the total electron yield (TEY) of Ru and B{sub 4}C were assessed in the absence of any surface charging effect. The experimental results were analyzed using semi-empirical Monte Carlo simulations and demonstrated that a native oxide film increased the TEY, and that this effect varied with film thickness. These phenomena were explained based on the effect of the backscattered electrons (BSEs) at the interface between Ru and RuO{sub 2}, as well as the lower potential barrier of RuO{sub 2}. Deviations in the material density from the theoretical values were attributed to the film deposition procedure based on fitting simulated TEY curves to experimental results. In the case of B{sub 4}C, the TEY was enhanced by the presence of a 0.8-nm-thick surface contamination film consisting of oxygenated hydrocarbons. The effect of the low potential barrier of the contamination film was found to be significant, as the density of the B{sub 4}C was much lower than that of the Ru. Comparing the simulation parameters generated in the present work with Joy’s database, it was found that the model and the input parameters used in the simulations were sufficiently accurate.

  7. Raising yield potential of wheat. III. Optimizing partitioning to grain while maintaining lodging resistance.

    Science.gov (United States)

    Foulkes, M John; Slafer, Gustavo A; Davies, William J; Berry, Pete M; Sylvester-Bradley, Roger; Martre, Pierre; Calderini, Daniel F; Griffiths, Simon; Reynolds, Matthew P

    2011-01-01

    A substantial increase in grain yield potential is required, along with better use of water and fertilizer, to ensure food security and environmental protection in future decades. For improvements in photosynthetic capacity to result in additional wheat yield, extra assimilates must be partitioned to developing spikes and grains and/or potential grain weight increased to accommodate the extra assimilates. At the same time, improvement in dry matter partitioning to spikes should ensure that it does not increase stem or root lodging. It is therefore crucial that improvements in structural and reproductive aspects of growth accompany increases in photosynthesis to enhance the net agronomic benefits of genetic modifications. In this article, six complementary approaches are proposed, namely: (i) optimizing developmental pattern to maximize spike fertility and grain number, (ii) optimizing spike growth to maximize grain number and dry matter harvest index, (iii) improving spike fertility through desensitizing floret abortion to environmental cues, (iv) improving potential grain size and grain filling, and (v) improving lodging resistance. Since many of the traits tackled in these approaches interact strongly, an integrative modelling approach is also proposed, to (vi) identify any trade-offs between key traits, hence to define target ideotypes in quantitative terms. The potential for genetic dissection of key traits via quantitative trait loci analysis is discussed for the efficient deployment of existing variation in breeding programmes. These proposals should maximize returns in food production from investments in increased crop biomass by increasing spike fertility, grain number per unit area and harvest index whilst optimizing the trade-offs with potential grain weight and lodging resistance.

  8. Global warming potential and greenhouse gas intensity in rice agriculture driven by high yields and nitrogen use efficiency

    Science.gov (United States)

    Zhang, Xiaoxu; Xu, Xin; Liu, Yinglie; Wang, Jinyang; Xiong, Zhengqin

    2016-05-01

    Our understanding of how global warming potential (GWP) and greenhouse gas intensity (GHGI) is affected by management practices aimed at food security with respect to rice agriculture remains limited. In the present study, a field experiment was conducted in China to evaluate the effects of integrated soil-crop system management (ISSM) on GWP and GHGI after accounting for carbon dioxide (CO2) equivalent emissions from all sources, including methane (CH4) and nitrous oxide (N2O) emissions, agrochemical inputs and farm operations and sinks (i.e., soil organic carbon sequestration). The ISSM mainly consisted of different nitrogen (N) fertilization rates and split, manure, Zn and Na2SiO3 fertilization and planting density for the improvement of rice yield and agronomic nitrogen use efficiency (NUE). Four ISSM scenarios consisting of different chemical N rates relative to the local farmers' practice (FP) rate were carried out, namely, ISSM-N1 (25 % reduction), ISSM-N2 (10 % reduction), ISSM-N3 (FP rate) and ISSM-N4 (25 % increase). The results showed that compared with the FP, the four ISSM scenarios significantly increased the rice yields by 10, 16, 28 and 41 % and the agronomic NUE by 75, 67, 35 and 40 %, respectively. In addition, compared with the FP, the ISSM-N1 and ISSM-N2 scenarios significantly reduced the GHGI by 14 and 18 %, respectively, despite similar GWPs. The ISSM-N3 and ISSM-N4 scenarios remarkably increased the GWP and GHGI by an average of 69 and 39 %, respectively. In conclusion, the ISSM strategies are promising for both food security and environmental protection, and the ISSM scenario of ISSM-N2 is the optimal strategy to realize high yields and high NUE together with low environmental impacts for this agricultural rice field.

  9. Enzyme oxidation of plant galactomannans yielding biomaterials with novel properties and applications, including as delivery systems.

    Science.gov (United States)

    Galante, Yves M; Merlini, Luca; Silvetti, Tiziana; Campia, Paola; Rossi, Bianca; Viani, Fiorenza; Brasca, Milena

    2018-06-01

    New biomaterials from renewable sources and the development of "functionalized biopolymers" are fields of growing industrial interest. Plant polysaccharides represent a valid alternative to traditional synthetic polymers, which are obtained from monomers of fossil, non-renewable origin. Several polysaccharides, either in their natural or chemically/biochemically modified forms, are currently employed in the biomedical, food and feed, and industrial fields, including packaging. Sustainable biochemical reactions, such as enzyme modifications of polysaccharides, open further possibilities for new product and process innovation. In the present review, we summarize the recent progress on enzyme oxidation of galactomannans (GM) from few leguminous plants (performed either with galactose oxidase or laccase) and we focus on the versatile and easily accessible laccase/TEMPO oxidative reaction. The latter causes a steep viscosity increase of GM water solutions and a transition of the gels from a viscous to an elastic form, due to formation of emiacetalic bonds and thus of internal cross-linking of the polymers. Following lyophilization of these hydrogels, stable aerogels can be obtained, which were shown to have good potential as delivery systems (DS) of actives. The active molecules tested and herewith described are polymyxin B, an antibiotic; nisin, an antimicrobial peptide; the enzymes lysozyme, protease and lipase; the mixture of the industrial microbiocides 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) and 2-methyl-4-isothiazolin-3-one (MIT). The advantages of such aerogel systems and the possibilities they open for future developments, including as DS, are described.

  10. Transesterification Of Kapok Oil Using Calcium Oxide Catalyst Methyl Esters Yield With Catalyst Loading

    Directory of Open Access Journals (Sweden)

    Yunusa Tukur

    2015-08-01

    Full Text Available Abstract This investigation was necessitated to find other feedstocks for biodiesel production that would not compete with food. Kapok oil with 0.8 FFA was transesterified with methanol using a heterogeneous catalyst CaO to determine its potential for biodiesel production. Methyl esters yields of 70.4 65.6 78.2 71.9 and 72.5 were obtained with catalyst loading of 0.8 1.2 1.6 2.0 and 2.4 wt. of oil. The products had high compositions of FFA and alcohols which indicates that the oil require more esterification to reduce the feedstock FFA far below 0.8. Some unsaturated hydrocarbons such as alkenes and alkynes were also formed which could make the products unstable.

  11. Simulation of nitrous oxide effluxes, crop yields and soil physical properties using the LandscapeDNDC model in managed ecosystem

    Science.gov (United States)

    Nyckowiak, Jedrzej; Lesny, Jacek; Haas, Edwin; Juszczak, Radoslaw; Kiese, Ralf; Butterbach-Bahl, Klaus; Olejnik, Janusz

    2014-05-01

    Modeling of nitrous oxide emissions from soil is very complex. Many different biological and chemical processes take place in soils which determine the amount of emitted nitrous oxide. Additionaly, biogeochemical models contain many detailed factors which may determine fluxes and other simulated variables. We used the LandscapeDNDC model in order to simulate N2O emissions, crop yields and soil physical properties from mineral cultivated soils in Poland. Nitrous oxide emissions from soils were modeled for fields with winter wheat, winter rye, spring barley, triticale, potatoes and alfalfa crops. Simulations were carried out for the plots of the Brody arable experimental station of Poznan University of Life Science in western Poland and covered the period 2003 - 2012. The model accuracy and its efficiency was determined by comparing simulations result with measurements of nitrous oxide emissions (measured with static chambers) from about 40 field campaigns. N2O emissions are strongly dependent on temperature and soil water content, hence we compared also simulated soil temperature at 10cm depth and soil water content at the same depth with the daily measured values of these driving variables. We compared also simulated yield quantities for each individual experimental plots with yield quantities which were measured in the period 2003-2012. We conclude that the LandscapeDNDC model is capable to simulate soil N2O emissions, crop yields and physical properties of soil with satisfactorily good accuracy and efficiency.

  12. On possibilities to decrease influence of oxidation processes on oil yield at oil shale retorting

    International Nuclear Information System (INIS)

    Yefimov, V.; Loeoeper, R.; Doilov, S.; Kundel, H.

    1993-01-01

    At the present technical level retorting is carried out so that an increase in specific air consumption results in an increase of oxygen ingress into the semi coking shaft. At the same time a direct relationship between the degree of volatiles pyrolysis and specific air consumption was observed. This regularity enables to assume that within the reaction volume there occurs most likely the thermo oxidative pyrolysis of volatile products, not the oxidation of oil shale as it is considered traditionally. The main source of oxygen ingress ed into the semi coking shaft at processing oil shale in retorts is the process of spent shale. This process is not fully elaborated for utilization in commercial scale and can not be arranged so that the ingress of oxygen into the smacking chamber could be eliminated. In case of a slower semi coke gasification process and reduced specific air consumption for gasification the absolute amount of oxygen ingress ed into the semi coking shaft also decreases. One of the efficient methods to decrease specific air consumption is to build furnaces into the semi coking chamber to obtain additional amount of heat carrier by combusting generator gas. The maximum effect is reached when steam-and-air blow is completely replaced by recycle gas: specific air consumption is reduced whereas recycle gas is deoxygenated in the cooling zone while passing through spent shale bed which has the temperature of about 500 deg C. Another possible source of oxygen to the semi coking shaft with heat carrier is production of flue gases by combusting recycle gas in burners built in retorts. We consider the recycle gas employed upon processing oil shale in retorts hardly to be an appreciable source of the oxygen ingress into the semi coking shaft. Additional amounts of residual oxygen containing in recycle gas fed into both cooling zone and furnaces are practically totally consumed at gas combusting and passing across the bed of semi coke heated up to approximately

  13. Evaluation of the development and yielding potential of Chenopodium quinoa Willd. under the climatic conditions of Europe. Part Two: Yielding potential of Chenopodium quinoa under different conditions

    Directory of Open Access Journals (Sweden)

    Krzysztof Gęsiński

    2012-12-01

    Full Text Available The evaluation of Chenopodium quinoa cultivation effects in Poland has been compared with European research results. It was found that the conditions in Europe are favorable to Chenopodium quinoa cultivation. Poland has the mean length of the vegetation period. The maximum value of this trait was found in Sweden. The conditions in Bydgoszcz (Poland are very favorable to the cultivation for green matter and favorable as far as the seed yield is concerned. The most favorable seed yield was recorded in Greece.

  14. The influence of zeta potential and yield stress on the filtration characteristics of a magnesium hydroxide simulant

    International Nuclear Information System (INIS)

    Biggs, Simon; Nabi, Rafiq; Poole, Colin; Patel, Ashok

    2007-01-01

    In the UK, irradiated fuels from Magnox reactors are often stored in water-filled ponds under alkaline conditions, so as to minimise corrosion of fuel cladding. This is important to prevent or reduce leakage of soluble fission products and actinides to the pond water. A variety of intermediate level wastes derived from Magnox materials are stored at power stations. Under these alkaline conditions, various species of magnesium are formed, of which magnesium hydroxide is the dominant material. The particle-fluid interactions are significant for the design and operation of facilities for hydraulic retrieval, filtration, dewatering and ion exchange treatment of fuel storage pond water and stored wet Magnox wastes. Here we describe a study of particulate properties and filtration characteristics of oxide particle simulants under laboratory conditions. Cake and medium resistance data were correlated across a range of pH conditions with electro-acoustic zeta potential and shear yield stress measurements, as a function of particle volume fractions. The influence of zeta potential on filtration properties arises directly from the interaction of particles within the sediment cake. (authors)

  15. Imbalance of heterologous protein folding and disulfide bond formation rates yields runaway oxidative stress

    Directory of Open Access Journals (Sweden)

    Tyo Keith EJ

    2012-03-01

    Full Text Available Abstract Background The protein secretory pathway must process a wide assortment of native proteins for eukaryotic cells to function. As well, recombinant protein secretion is used extensively to produce many biologics and industrial enzymes. Therefore, secretory pathway dysfunction can be highly detrimental to the cell and can drastically inhibit product titers in biochemical production. Because the secretory pathway is a highly-integrated, multi-organelle system, dysfunction can happen at many levels and dissecting the root cause can be challenging. In this study, we apply a systems biology approach to analyze secretory pathway dysfunctions resulting from heterologous production of a small protein (insulin precursor or a larger protein (α-amylase. Results HAC1-dependent and independent dysfunctions and cellular responses were apparent across multiple datasets. In particular, processes involving (a degradation of protein/recycling amino acids, (b overall transcription/translation repression, and (c oxidative stress were broadly associated with secretory stress. Conclusions Apparent runaway oxidative stress due to radical production observed here and elsewhere can be explained by a futile cycle of disulfide formation and breaking that consumes reduced glutathione and produces reactive oxygen species. The futile cycle is dominating when protein folding rates are low relative to disulfide bond formation rates. While not strictly conclusive with the present data, this insight does provide a molecular interpretation to an, until now, largely empirical understanding of optimizing heterologous protein secretion. This molecular insight has direct implications on engineering a broad range of recombinant proteins for secretion and provides potential hypotheses for the root causes of several secretory-associated diseases.

  16. Predictive tests to evaluate oxidative potential of engineered nanomaterials

    Science.gov (United States)

    Ghiazza, Mara; Carella, Emanuele; Oliaro-Bosso, Simonetta; Corazzari, Ingrid; Viola, Franca; Fenoglio, Ivana

    2013-04-01

    Oxidative stress constitutes one of the principal injury mechanisms through which particulate toxicants (asbestos, crystalline silica, hard metals) and engineered nanomaterials can induce adverse health effects. ROS may be generated indirectly by activated cells and/or directly at the surface of the material. The occurrence of these processes depends upon the type of material. Many authors have recently demonstrated that metal oxides and carbon-based nanoparticles may influence (increasing or decreasing) the generation of oxygen radicals in a cell environment. Metal oxide, such as iron oxides, crystalline silica, and titanium dioxide are able to generate free radicals via different mechanisms causing an imbalance within oxidant species. The increase of ROS species may lead to inflammatory responses and in some cases to the development of cancer. On the other hand carbon-based nanomaterials, such as fullerene, carbon nanotubes, carbon black as well as cerium dioxide are able to scavenge the free radicals generated acting as antioxidant. The high numbers of new-engineered nanomaterials, which are introduced in the market, are exponentially increasing. Therefore the definition of toxicological strategies is urgently needed. The development of acellular screening tests will make possible the reduction of the number of in vitro and in vivo tests to be performed. An integrated protocol that may be used to predict the oxidant/antioxidant potential of engineered nanoparticles will be here presented.

  17. Predictive tests to evaluate oxidative potential of engineered nanomaterials

    International Nuclear Information System (INIS)

    Ghiazza, Mara; Carella, Emanuele; Corazzari, Ingrid; Fenoglio, Ivana; Oliaro-Bosso, Simonetta; Viola, Franca

    2013-01-01

    Oxidative stress constitutes one of the principal injury mechanisms through which particulate toxicants (asbestos, crystalline silica, hard metals) and engineered nanomaterials can induce adverse health effects. ROS may be generated indirectly by activated cells and/or directly at the surface of the material. The occurrence of these processes depends upon the type of material. Many authors have recently demonstrated that metal oxides and carbon-based nanoparticles may influence (increasing or decreasing) the generation of oxygen radicals in a cell environment. Metal oxide, such as iron oxides, crystalline silica, and titanium dioxide are able to generate free radicals via different mechanisms causing an imbalance within oxidant species. The increase of ROS species may lead to inflammatory responses and in some cases to the development of cancer. On the other hand carbon-based nanomaterials, such as fullerene, carbon nanotubes, carbon black as well as cerium dioxide are able to scavenge the free radicals generated acting as antioxidant. The high numbers of new-engineered nanomaterials, which are introduced in the market, are exponentially increasing. Therefore the definition of toxicological strategies is urgently needed. The development of acellular screening tests will make possible the reduction of the number of in vitro and in vivo tests to be performed. An integrated protocol that may be used to predict the oxidant/antioxidant potential of engineered nanoparticles will be here presented.

  18. Potential for microbial oxidation of ferrous iron in basaltic glass.

    Science.gov (United States)

    Xiong, Mai Yia; Shelobolina, Evgenya S; Roden, Eric E

    2015-05-01

    Basaltic glass (BG) is an amorphous ferrous iron [Fe(II)]-containing material present in basaltic rocks, which are abundant on rocky planets such as Earth and Mars. Previous research has suggested that Fe(II) in BG can serve as an energy source for chemolithotrophic microbial metabolism, which has important ramifications for potential past and present microbial life on Mars. However, to date there has been no direct demonstration of microbially catalyzed oxidation of Fe(II) in BG. In this study, three different culture systems were used to investigate the potential for microbial oxidation of Fe(II) in BG, including (1) the chemolithoautotrophic Fe(II)-oxidizing, nitrate-reducing "Straub culture"; (2) the mixotrophic Fe(II)-oxidizing, nitrate-reducing organism Desulfitobacterium frappieri strain G2; and (3) indigenous microorganisms from a streambed Fe seep in Wisconsin. The BG employed consisted of clay and silt-sized particles of freshly quenched lava from the TEB flow in Kilauea, Hawaii. Soluble Fe(II) or chemically reduced NAu-2 smectite (RS) were employed as positive controls to verify Fe(II) oxidation activity in the culture systems. All three systems demonstrated oxidation of soluble Fe(II) and/or structural Fe(II) in RS, whereas no oxidation of Fe(II) in BG material was observed. The inability of the Straub culture to oxidize Fe(II) in BG was particularly surprising, as this culture can oxidize other insoluble Fe(II)-bearing minerals such as biotite, magnetite, and siderite. Although the reason for the resistance of the BG toward enzymatic oxidation remains unknown, it seems possible that the absence of distinct crystal faces or edge sites in the amorphous glass renders the material resistant to such attack. These findings have implications with regard to the idea that Fe(II)-Si-rich phases in basalt rocks could provide a basis for chemolithotrophic microbial life on Mars, specifically in neutral-pH environments where acid-promoted mineral dissolution and

  19. Safe handling of potential peroxide forming compounds and their corresponding peroxide yielded derivatives.

    Energy Technology Data Exchange (ETDEWEB)

    Sears, Jeremiah Matthew; Boyle, Timothy J.; Dean, Christopher J.

    2013-06-01

    This report addresses recent developments concerning the identification and handling of potential peroxide forming (PPF) and peroxide yielded derivative (PYD) chemicals. PPF chemicals are described in terms of labeling, shelf lives, and safe handling requirements as required at SNL. The general peroxide chemistry concerning formation, prevention, and identification is cursorily presented to give some perspective to the generation of peroxides. The procedure for determining peroxide concentrations and the proper disposal methods established by the Hazardous Waste Handling Facility are also provided. Techniques such as neutralization and dilution are provided for the safe handling of any PYD chemicals to allow for safe handling. The appendices are a collection of all available SNL documentation pertaining to PPF/PYD chemicals to serve as a single reference.

  20. Effect of Climate and Management Factors on Potential and Gap of Wheat Yield in Iran with Using WOFOST Model

    Directory of Open Access Journals (Sweden)

    A Koocheki

    2017-10-01

    Full Text Available Introduction Human diets strongly rely on wheat (Triticum aestivum L.. Its production has increased dramatically during the past 50 years, partly due to area extension and new varieties but mainly as a consequence of intensified land management and introduction of new technologies. For the future, a continuous strong increase in the demand for agricultural products is expected. It is highly unlikely that this increasing demand will be satisfied by area expansion because productive land is scarce and also increasingly demanded by non-agricultural uses. The role of agricultural intensification as key to increasing actual crop yields and food supply has been discussed in several studies. However, in many regions, increases in grain yields have been declining Inefficient management of agricultural land may cause deviations of actual from potential crop yields: the yield gap. At the global scale little information is available on the spatial distribution of agricultural yield gaps and the potential for agricultural intensification. Actual yield is mostly lower than potential yield due to inefficient management and technological that difference between these yields is considered as yield gap. Understanding of relative share of every management factors in yield gap could be as one of the important keys to reduce gap and close actual yield to potential yield. Materials and Methods In order to evaluate the amount of wheat yield gap and also relative share of management and technological variables in yield gap, frontier production function was used which is a multi-variable regression. The frontier production function to be estimated is a Cobb-Douglas function as proposed by Coelli et al. (2005. Cobb-Douglas functions are extensively used in agricultural production studies to explain returns to scale. We propose a methodology to explain the spatial variation of the potential for intensification and identifying the nature of the constraints for further

  1. Simulated potential and water-limited yields of cocoa under different agro-ecological zones in Peninsular Malaysia

    NARCIS (Netherlands)

    Zabawi, A.G.M.; Gerritsma, W.

    2009-01-01

    The yield of cocoa under potential and water-limited production levels in different agro-ecological zones was simulated using cocoa model CASE2. For both production levels, the yield was simulated using five years of elirnatic data (1991-1995) and plant data of three-year-old plant. The results

  2. Diversity of cacao trees in Waslala, Nicaragua: associations between genotype spectra, product quality and yield potential.

    Science.gov (United States)

    Trognitz, Bodo; Cros, Emile; Assemat, Sophie; Davrieux, Fabrice; Forestier-Chiron, Nelly; Ayestas, Eusebio; Kuant, Aldo; Scheldeman, Xavier; Hermann, Michael

    2013-01-01

    The sensory quality and the contents of quality-determining chemical compounds in unfermented and fermented cocoa from 100 cacao trees (individual genotypes) representing groups of nine genotype spectra (GG), grown at smallholder plantings in the municipality of Waslala, Nicaragua, were evaluated for two successive harvest periods. Cocoa samples were fermented using a technique mimicking recommended on-farm practices. The sensory cocoa quality was assessed by experienced tasters, and seven major chemical taste compounds were quantified by near infrared spectrometry (NIRS). The association of the nine, partially admixed, genotype spectra with the analytical and sensory quality parameters was tested. The individual parameters were analyzed as a function of the factors GG and harvest (including the date of fermentation), individual trees within a single GG were used as replications. In fermented cocoa, significant GG-specific differences were observed for methylxanthines, theobromine-to-caffeine (T/C) ratio, total fat, procyanidin B5 and epicatechin, as well as the sensory attributes global score, astringency, and dry fruit aroma, but differences related to harvest were also apparent. The potential cocoa yield was also highly determined by the individual GG, although there was significant tree-to-tree variation within every single GG. Non-fermented samples showed large harvest-to-harvest variation of their chemical composition, while differences between GG were insignificant. These results suggest that selection by the genetic background, represented here by groups of partially admixed genotype spectra, would be a useful strategy toward enhancing quality and yield of cocoa in Nicaragua. Selection by the GG within the local, genetically segregating populations of seed-propagated cacao, followed by clonal propagation of best-performing individuals of the selected GG could be a viable alternative to traditional propagation of cacao by seed from open pollination. Fast and

  3. Diversity of cacao trees in Waslala, Nicaragua: associations between genotype spectra, product quality and yield potential.

    Directory of Open Access Journals (Sweden)

    Bodo Trognitz

    Full Text Available The sensory quality and the contents of quality-determining chemical compounds in unfermented and fermented cocoa from 100 cacao trees (individual genotypes representing groups of nine genotype spectra (GG, grown at smallholder plantings in the municipality of Waslala, Nicaragua, were evaluated for two successive harvest periods. Cocoa samples were fermented using a technique mimicking recommended on-farm practices. The sensory cocoa quality was assessed by experienced tasters, and seven major chemical taste compounds were quantified by near infrared spectrometry (NIRS. The association of the nine, partially admixed, genotype spectra with the analytical and sensory quality parameters was tested. The individual parameters were analyzed as a function of the factors GG and harvest (including the date of fermentation, individual trees within a single GG were used as replications. In fermented cocoa, significant GG-specific differences were observed for methylxanthines, theobromine-to-caffeine (T/C ratio, total fat, procyanidin B5 and epicatechin, as well as the sensory attributes global score, astringency, and dry fruit aroma, but differences related to harvest were also apparent. The potential cocoa yield was also highly determined by the individual GG, although there was significant tree-to-tree variation within every single GG. Non-fermented samples showed large harvest-to-harvest variation of their chemical composition, while differences between GG were insignificant. These results suggest that selection by the genetic background, represented here by groups of partially admixed genotype spectra, would be a useful strategy toward enhancing quality and yield of cocoa in Nicaragua. Selection by the GG within the local, genetically segregating populations of seed-propagated cacao, followed by clonal propagation of best-performing individuals of the selected GG could be a viable alternative to traditional propagation of cacao by seed from open

  4. Diversity of Cacao Trees in Waslala, Nicaragua: Associations between Genotype Spectra, Product Quality and Yield Potential

    Science.gov (United States)

    Trognitz, Bodo; Cros, Emile; Assemat, Sophie; Davrieux, Fabrice; Forestier-Chiron, Nelly; Ayestas, Eusebio; Kuant, Aldo; Scheldeman, Xavier; Hermann, Michael

    2013-01-01

    The sensory quality and the contents of quality-determining chemical compounds in unfermented and fermented cocoa from 100 cacao trees (individual genotypes) representing groups of nine genotype spectra (GG), grown at smallholder plantings in the municipality of Waslala, Nicaragua, were evaluated for two successive harvest periods. Cocoa samples were fermented using a technique mimicking recommended on-farm practices. The sensory cocoa quality was assessed by experienced tasters, and seven major chemical taste compounds were quantified by near infrared spectrometry (NIRS). The association of the nine, partially admixed, genotype spectra with the analytical and sensory quality parameters was tested. The individual parameters were analyzed as a function of the factors GG and harvest (including the date of fermentation), individual trees within a single GG were used as replications. In fermented cocoa, significant GG-specific differences were observed for methylxanthines, theobromine-to-caffeine (T/C) ratio, total fat, procyanidin B5 and epicatechin, as well as the sensory attributes global score, astringency, and dry fruit aroma, but differences related to harvest were also apparent. The potential cocoa yield was also highly determined by the individual GG, although there was significant tree-to-tree variation within every single GG. Non-fermented samples showed large harvest-to-harvest variation of their chemical composition, while differences between GG were insignificant. These results suggest that selection by the genetic background, represented here by groups of partially admixed genotype spectra, would be a useful strategy toward enhancing quality and yield of cocoa in Nicaragua. Selection by the GG within the local, genetically segregating populations of seed-propagated cacao, followed by clonal propagation of best-performing individuals of the selected GG could be a viable alternative to traditional propagation of cacao by seed from open pollination. Fast and

  5. Impact of NDF degradability of corn silage on the milk yield potential of dairy cows

    Directory of Open Access Journals (Sweden)

    Mauro Spanghero

    2010-01-01

    Full Text Available The neutral detergent fibre (NDF degradability of corn silage samples, measured in vitro (ivNDFd by a filter bag system, was used to examine (i the relationship between the ivNDFd and that calculated from acid detergent lignin (L content (NDFd and (ii the impact of ivNDFd variations on the predicted milk yield (MY of dairy cows fed corn silage based diets. A total of 173 samples of corn silage were collected during a period of three years (2001-03 in different dairy farms of the Po Valley (Northern Italy. Each sample was analysed for chemical composition and was also tested in triplicate for the ivNDFd using the DaisyII incubator (Ankom, Tech. Co., Fairport, NY, USA with incubation time of 48hs. Moreover, the NDFd of samples was calculated from the L contents, while the measured ivNDFd values were used to estimate the NEl, the potential dry matter intakes (DMI and to predict the MY of cows. Corn silage samples of the three years were similar for NDF and starch contents (44.2 and 30.7% DM, on average, respectively while samples from 2003, in comparison with 2001 and 2002, had lower crude protein (6.9 vs 8.3-8.4% DM, P<0.01 and L contents (3.3 vs 3.6-3.9% DM, P<0.01 and higher ivNDFd values (53.3 vs 45.6-47.8%, P<0.01. The relationship between ivNDFd and NDFd was weak (R2=0.09, not significant. The MY predicted from the NEl content and DMI of corn silage (5.5 MJ/kg DM and 8.9 kg/d minus the maintenance energy costs, was 11.5 kg/d on average (coefficient of variation 20%. Our simulations indicate that a variation of ivNDFd by +1.0% changes the NEl of corn silage to have an expected variation in milk yield of +0.15 kg/d. If the ivNDFd is also used to predict the corn silage DMI then a +1.0% variation in ivNDFd of corn silage produces an overall +0.23 kg/d MY variation. The present results indicate that ivNDFd is highly variable in corn silage populations and differences in this nutritional parameter have an appreciable impact on the predicted milk

  6. Using Satellite Data to Identify the Causes of and Potential Solutions for Yield Gaps in India's Wheat Belt

    Science.gov (United States)

    Jain, M.; Singh, B.; Srivastava, A.; Malik, R. K.; McDonald, A.; Lobell, D. B.

    2017-12-01

    Food security will be increasingly challenged by climate change, natural resource degradation, and population growth. Wheat yields, in particular, have already stagnated in many regions and will be further affected by warming temperatures. Despite these challenges, wheat yields can be increased by improving management practices in regions with existing yield gaps. We present two studies that are using satellite data to better understand the factors contributing to yield gaps and potential interventions to close yield gaps in India's main wheat belt, the Indo-Gangetic Plains (IGP). To identify the magnitude and causes of current yield gaps, we produced 30 meter resolution yield maps from 2001 to 2015 using Landsat sallite data and a new method that translates satellite vegetation indices to yield estimates using crop model simulations, bypassing the need for ground calibration data. This is one of the first attempts to apply this method to a smallholder agriculture system, where ground calibration data are rarely available. We find that yields can be increased by 11% on average and up to 32% in the eastern IGP by improving management to current best practices within a given district. Additionally, if current best practices from the highest-yielding state of Punjab are implemented in the eastern IGP, yields could increase by almost 110%. Considering the factors that most influence yields, later sow dates and warmer temperatures are most associated with low yields across the IGP. This suggests that strategies to reduce the negative effects of heat stress, like earlier sowing and planting heat-tolerant wheat varieties, are critical to increasing wheat yields in this globally-important agricultural region. We also apply this method to high-resolution micro-satellite data (impacts of a new fertilizer spreader technology and identify whether satellite data can be used to appropriately target this intervention.

  7. Nature of the concentration thresholds of europium atom yield from the oxidized tungsten surface under electron stimulated desorption

    CERN Document Server

    Davydov, S Y

    2002-01-01

    The nature of the electron-stimulated desorption (ESD) of the europium atoms by the E sub e irradiating electrons energies, equal to 50 and 80 eV, as well as peculiarities of the Eu atoms yield dependence on their concentration on the oxidized tungsten surface are discussed. It is shown, that the ESD originates by the electron transition from the interval 5p- or 5s shell of the tungsten surface atom onto the oxygen external unfilled 2p-level

  8. Heterogeneous oxidation of SO2 by O3-aged black carbon and its dithiothreitol oxidative potential.

    Science.gov (United States)

    Xu, Weiwei; Li, Qian; Shang, Jing; Liu, Jia; Feng, Xiang; Zhu, Tong

    2015-10-01

    Ozone (O3) is an important atmospheric oxidant. Black carbon (BC) particles released into the atmosphere undergo an aging process via O3 oxidation. O3-aged BC particles may change their uptake ability toward trace reducing gases such as SO2 in the atmosphere, leading to different environmental and health effects. In this paper, the heterogeneous reaction process between O3-aged BC and SO2 was explored via in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Combined with ion chromatography (IC), DRIFTS was used to qualitatively and quantitatively analyze the sulfate product. The results showed that O3-aged BC had stronger SO2 oxidation ability than fresh BC, and the reactive species/sites generated on the surface had an important role in the oxidation of SO2. Relative humidity or 254nm UV (ultraviolet) light illumination enhanced the oxidation uptake of SO2 on O3-aged BC. The oxidation potentials of the BC particles were detected via dithiothreitol (DTT) assay. The DTT activity over BC was decreased in the process of SO2 reduction, with the consumption of oxidative active sites. Copyright © 2015. Published by Elsevier B.V.

  9. Potential toxicity of superparamagnetic iron oxide nanoparticles (SPION

    Directory of Open Access Journals (Sweden)

    Neenu Singh

    2010-09-01

    Full Text Available Superparamagnetic iron oxide nanoparticles (SPION are being widely used for various biomedical applications, for example, magnetic resonance imaging, targeted delivery of drugs or genes, and in hyperthermia. Although, the potential benefits of SPION are considerable, there is a distinct need to identify any potential cellular damage associated with these nanoparticles. Besides focussing on cytotoxicity, the most commonly used determinant of toxicity as a result of exposure to SPION, this review also mentions the importance of studying the subtle cellular alterations in the form of DNA damage and oxidative stress. We review current studies and discuss how SPION, with or without different surface coating, may cause cellular perturbations including modulation of actin cytoskeleton, alteration in gene expression profiles, disturbance in iron homeostasis and altered cellular responses such as activation of signalling pathways and impairment of cell cycle regulation. The importance of protein–SPION interaction and various safety considerations relating to SPION exposure are also addressed.

  10. Winter sowing of adapted lines as a potential yield increase strategy in lentil (Lens culinaris Medik.

    Directory of Open Access Journals (Sweden)

    Abel Barrios

    2016-06-01

    Full Text Available Lentil (Lens culinaris Medik. subsp. culinaris is a traditional crop in Spain although current grain yield in Spain is relatively low and unstable. The effect of an early sowing date (winter sowing on yield in the Spanish Central Plateau (meseta was analyzed comparing it to the traditional spring sowing. Yield from eleven cultivars currently available for sowing in Spain and two F6:7  populations of recombinant inbred lines (RIL, ´Precoz´ × ´WA8649041´ (89 lines and ´BGE016365´ × ´ILL1918´ (118 lines, was evaluated in winter and spring sowing dates for three seasons (2005/06, 2006/07 and 2007/08 and two localities. Yield and stability were assessed by the method of consistency of performance with some modifications. When comparing with the best currently available cultivars sown in the traditional spring sowing date, (with an estimated average yield of 43.9 g/m in our experimental conditions, winter sowing using adapted breeding lines proved to be a suitable strategy for increasing lentil yield and yield stability in the Spanish meseta, with an average yield increase of 111% (reaching an estimated yield of 92.8 g/m. Results point to that lentil production can greatly increase in the Spanish meseta if adequate plant materials, such as some of the lines analyzed, are sown at late fall.

  11. Winter sowing of adapted lines as a potential yield increase strategy in lentil (Lens culinaris Medik.)

    Energy Technology Data Exchange (ETDEWEB)

    Barrios, A.; Aparicio, T.; Rodríguez, M.J.; Pérez de la Vega, M.; Caminero, C.

    2016-11-01

    Lentil (Lens culinaris Medik. subsp. culinaris) is a traditional crop in Spain although current grain yield in Spain is relatively low and unstable. The effect of an early sowing date (winter sowing) on yield in the Spanish Central Plateau (meseta) was analyzed comparing it to the traditional spring sowing. Yield from eleven cultivars currently available for sowing in Spain and two F6:7 populations of recombinant inbred lines (RIL), ´Precoz´ × ´WA8649041´ (89 lines) and ´BGE016365´ × ´ILL1918´ (118 lines), was evaluated in winter and spring sowing dates for three seasons (2005/06, 2006/07 and 2007/08) and two localities. Yield and stability were assessed by the method of consistency of performance with some modifications. When comparing with the best currently available cultivars sown in the traditional spring sowing date, (with an estimated average yield of 43.9 g/m in our experimental conditions), winter sowing using adapted breeding lines proved to be a suitable strategy for increasing lentil yield and yield stability in the Spanish meseta, with an average yield increase of 111% (reaching an estimated yield of 92.8 g/m). Results point to that lentil production can greatly increase in the Spanish meseta if adequate plant materials, such as some of the lines analyzed, are sown at late fall. (Author)

  12. Oxidative potential of subway PM2.5

    Science.gov (United States)

    Moreno, Teresa; Kelly, Frank J.; Dunster, Chrissi; Oliete, Ana; Martins, Vânia; Reche, Cristina; Minguillón, Maria Cruz; Amato, Fulvio; Capdevila, Marta; de Miguel, Eladio; Querol, Xavier

    2017-01-01

    Air quality in subway systems is of interest not only because particulate matter (PM) concentrations can be high, but also because of the peculiarly metalliferous chemical character of the particles, most of which differ radically from those of outdoor ambient air. We report on the oxidative potential (OP) of PM2.5 samples collected in the Barcelona subway system in different types of stations. The PM chemical composition of these samples showed typically high concentrations of Fe, Total Carbon, Ba, Cu, Mn, Zn and Cr sourced from rail tracks, wheels, catenaries, brake pads and pantographs. Two toxicological indicators of oxidative activity, ascorbic acid (AA) oxidation (expressed as OPAA μg-1 or OPAA m-3) and glutathione (GSH) oxidation (expressed as OPGSH μg-1 or OPGSH m-3), showed low OP for all samples (compared with outdoor air) but considerable variation between stations (0.9-2.4 OPAA μg-1; 0.4-1.9 OPGSH μg-1). Results indicate that subway PM toxicity is not related to variations in PM2.5 concentrations produced by ventilation changes, tunnel works, or station design, but may be affected more by the presence of metallic trace elements such as Cu and Sb sourced from brakes and pantographs. The OP assays employed do not reveal toxic effects from the highly ferruginous component present in subway dust.

  13. Assessments of Future Maize Yield Potential Changes in the Korean Peninsula Using Multiple Crop Models

    Science.gov (United States)

    Kim, S. H.; Lim, C. H.; Kim, J.; Lee, W. K.; Kafatos, M.

    2016-12-01

    The Korean Peninsula has unique agricultural environment due to the differences of political and socio-economical system between Republic of Korea (SK, hereafter) and Democratic Peoples' Republic of Korea (NK, hereafter). NK has been suffering lack of food supplies caused by natural disasters, land degradation and political failure. The neighboring developed country SK has better agricultural system but very low food self-sufficiency rate. Maize is an important crop in both countries since it is staple food for NK and SK is No. 2 maize importing country in the world after Japan. Therefore, evaluating maize yield potential (Yp) in the two distinct regions is essential to assess food security under climate change and variability. In this study, we utilized multiple process-based crop models, having ability of regional scale assessment, to evaluate maize Yp and assess the model uncertainties -EPIC, GEPIC, DSSAT, and APSIM model that has capability of regional scale expansion (apsimRegions). First we evaluated each crop model for 3 years from 2012 to 2014 using reanalysis data (RDAPS; Regional Data Assimilation and Prediction System produced by Korea Meteorological Agency) and observed yield data. Each model performances were compared over the different regions in the Korean Peninsula having different local climate characteristics. To quantify of the major influence of at each climate variables, we also conducted sensitivity test using 20 years of climatology in historical period from 1981 to 2000. Lastly, the multi-crop model ensemble analysis was performed for future period from 2031 to 2050. The required weather variables projected for mid-century were employed from COordinated Regional climate Downscaling EXperiment (CORDEX) East Asia. The high-resolution climate data were obtained from multiple regional climate models (RCM) driven by multiple climate scenarios projected from multiple global climate models (GCMs) in conjunction with multiple greenhouse gas

  14. Intermolecular potential energy surface and thermophysical properties of ethylene oxide.

    Science.gov (United States)

    Crusius, Johann-Philipp; Hellmann, Robert; Hassel, Egon; Bich, Eckard

    2014-10-28

    A six-dimensional potential energy hypersurface (PES) for two interacting rigid ethylene oxide (C2H4O) molecules was determined from high-level quantum-chemical ab initio calculations. The counterpoise-corrected supermolecular approach at the MP2 and CCSD(T) levels of theory was utilized to determine interaction energies for 10178 configurations of two molecules. An analytical site-site potential function with 19 sites per ethylene oxide molecule was fitted to the interaction energies and fine tuned to agree with data for the second acoustic virial coefficient from accurate speed of sound measurements. The PES was validated by computing the second virial coefficient, shear viscosity, and thermal conductivity. The values of these properties are substantiated by the best experimental data as they tend to fall within the uncertainty intervals and also obey the experimental temperature functions, except for viscosity, where experimental data are insufficient. Due to the lack of reliable data, especially for the transport properties, our calculated values are currently the most accurate estimates for these properties of ethylene oxide.

  15. Sputtering yields and surface chemical modification of tin-doped indium oxide in hydrocarbon-based plasma etching

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hu; Karahashi, Kazuhiro; Hamaguchi, Satoshi, E-mail: hamaguch@ppl.eng.osaka-u.ac.jp [Center for Atomic and Molecular Technologies, Osaka University, Yamadaoka 2-1, Suita 565-0871 (Japan); Fukasawa, Masanaga; Nagahata, Kazunori; Tatsumi, Tetsuya [Device and Material R& D Group, RDS Platform, Sony Corporation, Kanagawa 243-0014 (Japan)

    2015-11-15

    Sputtering yields and surface chemical compositions of tin-doped indium oxide (or indium tin oxide, ITO) by CH{sup +}, CH{sub 3}{sup +}, and inert-gas ion (He{sup +}, Ne{sup +}, and Ar{sup +}) incidence have been obtained experimentally with the use of a mass-selected ion beam system and in-situ x-ray photoelectron spectroscopy. It has been found that etching of ITO is chemically enhanced by energetic incidence of hydrocarbon (CH{sub x}{sup +}) ions. At high incident energy incidence, it appears that carbon of incident ions predominantly reduce indium (In) of ITO and the ITO sputtering yields by CH{sup +} and CH{sub 3}{sup +} ions are found to be essentially equal. At lower incident energy (less than 500 eV or so), however, a hydrogen effect on ITO reduction is more pronounced and the ITO surface is more reduced by CH{sub 3}{sup +} ions than CH{sup +} ions. Although the surface is covered more with metallic In by low-energy incident CH{sub 3}{sup +} ions than CH{sup +} ions and metallic In is in general less resistant against physical sputtering than its oxide, the ITO sputtering yield by incident CH{sub 3}{sup +} ions is found to be lower than that by incident CH{sup +} ions in this energy range. A postulation to account for the relation between the observed sputtering yield and reduction of the ITO surface is also presented. The results presented here offer a better understanding of elementary surface reactions observed in reactive ion etching processes of ITO by hydrocarbon plasmas.

  16. Oxidized zirconium: a potentially longer lasting hip implant

    International Nuclear Information System (INIS)

    Good, V.; Widding, K.; Hunter, G.; Heuer, D.

    2005-01-01

    Because younger, more active patients are receiving total hip replacements, it is necessary to develop materials, which would increase the life span of the implants and challenge their wear potential under adverse conditions. Oxidized zirconium (OxZr) is a metal with the surface transformed to ceramic by oxidation that offers low fracture risk and excellent abrasion resistance. This study compared wear of polyethylene (non-irradiated and highly crosslinked) with OxZr and CoCr heads under smooth and rough (clinically relevant) conditions. Wear was up to 15-fold less and up to 4-fold fewer particles were produced when coupled with OxZr than with CoCr, demonstrating that OxZr heads should increase clinical implant longevity

  17. Topotactic reduction yielding black titanium oxide nanostructures as metallic electronic conductors.

    Science.gov (United States)

    Tominaka, Satoshi

    2012-10-01

    Detailed analyses of reduced, single crystal, rutile-type TiO(2) via high-resolution transmission electron microscopy (TEM) are reported which reveal that the reduction proceeds topotactically via interstitial diffusion of Ti ions at low temperature, around 350 °C. This important finding encouraged the production of various nanostructured reduced titanium oxides from TiO(2) precursors with morphology retention, and in the process, the synthesis of black titanium oxide nanorods using TiO(2) nanorods was demonstrated. Interestingly, as opposed to the semiconductive behavior of Ti(2)O(3) synthesized at high temperature, topotactically synthesized Ti(2)O(3) exhibits metallic electrical resistance, and the value at room temperature is quite low (topotactically synthesized Ti(2)O(3). This work shows that topotactically reduced titanium oxides can have fascinating properties as well as nanostructures.

  18. Variation of Potential Yield of Hybrid Population of Robusta coffee (Coffea canepor

    Directory of Open Access Journals (Sweden)

    Novie Pranata Erdiansyah

    2014-08-01

    Full Text Available The low yield of Robusta coffee in Indonesia may be due to the use of planting materials derived from seeds. The research objective was to determine the variation of Robusta coffee yield wich local propagated by using seeds. The study was conducted in Kaliwining experimental Station of ICCRI (Indonesian Coffee andCocoa Research Institute. There were two populations observed. Number of progeny used in this study were 186 genotypes consisting of two groups from crossesBP 409 x Q 121 with 89 progenies and BP 961 x BP 409 with 81 progenies. The results showed that planting materials from seeds exhibit properties mixed results.Progeny that have the best results (yield more than 2 ton/ha not more than 5% of the total population. In both populations there is a big difference between the progenythat has high and low yield. Highest yield B population could reach 2,500 kg/ha and the C population reached 2,200 kg/ha. The lowest yield can only produce coffee270 kg/ha in populations B and 120 kg/ha in population C.Key words: Coffea canephora, hybrid, variation, yield

  19. Assessments of Maize Yield Potential in the Korean Peninsula Using Multiple Crop Models

    Science.gov (United States)

    Kim, S. H.; Myoung, B.; Lim, C. H.; Lee, S. G.; Lee, W. K.; Kafatos, M.

    2015-12-01

    The Korean Peninsular has unique agricultural environments due to the differences in the political and socio-economical systems between the Republic of Korea (SK, hereafter) and the Democratic Peoples' Republic of Korea (NK, hereafter). NK has been suffering from the lack of food supplies caused by natural disasters, land degradation and failed political system. The neighboring developed country SK has a better agricultural system but very low food self-sufficiency rate (around 1% of maize). Maize is an important crop in both countries since it is staple food for NK and SK is No. 2 maize importing country in the world after Japan. Therefore evaluating maize yield potential (Yp) in the two distinct regions is essential to assess food security under climate change and variability. In this study, we have utilized multiple process-based crop models capable of regional-scale assessments to evaluate maize Yp over the Korean Peninsula - the GIS version of EPIC model (GEPIC) and APSIM model that can be expanded to regional scales (APSIM regions). First we evaluated model performance and skill for 20 years from 1991 to 2010 using reanalysis data (Local Data Assimilation and Prediction System (LDAPS); 1.5km resolution) and observed data. Each model's performances were compared over different regions within the Korean Peninsula of different regional climate characteristics. To quantify the major influence of individual climate variables, we also conducted a sensitivity test using 20 years of climatology. Lastly, a multi-model ensemble analysis was performed to reduce crop model uncertainties. The results will provide valuable information for estimating the climate change or variability impacts on Yp over the Korean Peninsula.

  20. Role of nitric oxide in cadmium-induced stress on growth, photosynthetic components and yield of Brassica napus L.

    Science.gov (United States)

    Jhanji, Shalini; Setia, R C; Kaur, Navjyot; Kaur, Parminder; Setia, Neelam

    2012-11-01

    Experiments were carried out to study the effect of cadmium (Cd) and exogenous nitric oxide (NO) on growth, photosynthetic attributes, yield components and structural features of Brassica napus L. (cv. GSL 1). Cadmium in the growth medium at different levels (1, 2 and 4 Mm) retarded plant growth viz. shoot (27%) and root (51%) length as compared to control. The accumulation of total dry matter and its partitioning to different plant parts was also reduced by 31% due to Cd toxicity. Photosynthetic parameters viz., leaf area plant(-1) (51%), total Chl (27%), Chl a / Chl b ratio (22%) and Hill reaction activity of chloroplasts (42%) were greatly reduced in Cd-treated plants. Cd treatments adversely affected various yield parameters viz., number of branches (23) and siliquae plant(-1) (246), seed number siliqua(-1) (10.3), 1000-seed weight (2.30g) and seed yield plant(-1) (7.09g). Different Cd treatments also suppressed the differentiation of various tissues like vessels in the root with a maximum inhibition caused by 4mM Cd. Exogenous application of nitric oxide (NO) improved the various morpho-physiological and photosynthetic parameters in control as well as Cd-treated plants.

  1. Potential disruption of protein-protein interactions by graphene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Mei [Department of Physics, Institute of Quantitative Biology, Zhejiang University, Hangzhou 310027 (China); Kang, Hongsuk; Luan, Binquan [Computational Biological Center, IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Yang, Zaixing [Institute of Quantitative Biology and Medicine, SRMP and RAD-X, and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123 (China); Zhou, Ruhong, E-mail: ruhong@us.ibm.com [Department of Physics, Institute of Quantitative Biology, Zhejiang University, Hangzhou 310027 (China); Computational Biological Center, IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Department of Chemistry, Columbia University, New York, New York 10027 (United States)

    2016-06-14

    Graphene oxide (GO) is a promising novel nanomaterial with a wide range of potential biomedical applications due to its many intriguing properties. However, very little research has been conducted to study its possible adverse effects on protein-protein interactions (and thus subsequent toxicity to human). Here, the potential cytotoxicity of GO is investigated at molecular level using large-scale, all-atom molecular dynamics simulations to explore the interaction mechanism between a protein dimer and a GO nanosheet oxidized at different levels. Our theoretical results reveal that GO nanosheet could intercalate between the two monomers of HIV-1 integrase dimer, disrupting the protein-protein interactions and eventually lead to dimer disassociation as graphene does [B. Luan et al., ACS Nano 9(1), 663 (2015)], albeit its insertion process is slower when compared with graphene due to the additional steric and attractive interactions. This study helps to better understand the toxicity of GO to cell functions which could shed light on how to improve its biocompatibility and biosafety for its wide potential biomedical applications.

  2. Potential disruption of protein-protein interactions by graphene oxide

    International Nuclear Information System (INIS)

    Feng, Mei; Kang, Hongsuk; Luan, Binquan; Yang, Zaixing; Zhou, Ruhong

    2016-01-01

    Graphene oxide (GO) is a promising novel nanomaterial with a wide range of potential biomedical applications due to its many intriguing properties. However, very little research has been conducted to study its possible adverse effects on protein-protein interactions (and thus subsequent toxicity to human). Here, the potential cytotoxicity of GO is investigated at molecular level using large-scale, all-atom molecular dynamics simulations to explore the interaction mechanism between a protein dimer and a GO nanosheet oxidized at different levels. Our theoretical results reveal that GO nanosheet could intercalate between the two monomers of HIV-1 integrase dimer, disrupting the protein-protein interactions and eventually lead to dimer disassociation as graphene does [B. Luan et al., ACS Nano 9(1), 663 (2015)], albeit its insertion process is slower when compared with graphene due to the additional steric and attractive interactions. This study helps to better understand the toxicity of GO to cell functions which could shed light on how to improve its biocompatibility and biosafety for its wide potential biomedical applications.

  3. Effects of land cover change on moisture availability and potential crop yield in the world’s breadbaskets

    International Nuclear Information System (INIS)

    Bagley, Justin E; Desai, Ankur R; Dirmeyer, Paul A; Foley, Jonathan A

    2012-01-01

    The majority of the world’s food production capability is inextricably tied to global precipitation patterns. Changes in moisture availability—whether from changes in climate from anthropogenic greenhouse gas emissions or those induced by land cover change (LCC)—can have profound impacts on food production. In this study, we examined the patterns of evaporative sources that contribute to moisture availability over five major global food producing regions (breadbaskets), and the potential for land cover change to influence these moisture sources by altering surface evapotranspiration. For a range of LCC scenarios we estimated the impact of altered surface fluxes on crop moisture availability and potential yield using a simplified linear hydrologic model and a state-of-the-art ecosystem and crop model. All the breadbasket regions were found to be susceptible to reductions in moisture owing to perturbations in evaporative source (ES) from LCC, with reductions in moisture availability ranging from 7 to 17% leading to potential crop yield reductions of 1–17%, which are magnitudes comparable to the changes anticipated with greenhouse warming. The sensitivity of these reductions in potential crop yield to varying magnitudes of LCC was not consistent among regions. Two variables explained most of these differences: the first was the magnitude of the potential moisture availability change, with regions exhibiting greater reductions in moisture availability also tending to exhibit greater changes in potential yield; the second was the soil moisture within crop root zones. Regions with mean growing season soil moisture fractions of saturation >0.5 typically had reduced impacts on potential crop yield. Our results indicate the existence of LCC thresholds that have the capability to create moisture shortages adversely affecting crop yields in major food producing regions, which could lead to future food supply disruptions in the absence of increased irrigation or other

  4. Sensitivity of commercial pumpkin yield to potential decline among different groups of pollinating bees

    Science.gov (United States)

    Eckerter, Philipp W.; Schirmel, Jens; Cresswell, James E.; Entling, Martin H.

    2017-01-01

    The yield of animal-pollinated crops is threatened by bee declines, but its precise sensitivity is poorly known. We therefore determined the yield dependence of Hokkaido pumpkin in Germany on insect pollination by quantifying: (i) the relationship between pollen receipt and fruit set and (ii) the cumulative pollen deposition of each pollinator group. We found that approximately 2500 pollen grains per flower were needed to maximize fruit set. At the measured rates of flower visitation, we estimated that bumblebees (21 visits/flower lifetime, 864 grains/visit) or honeybees (123 visits, 260 grains) could individually achieve maximum crop yield, whereas halictid bees are ineffective (11 visits, 16 grains). The pollinator fauna was capable of delivering 20 times the necessary amount of pollen. We therefore estimate that pumpkin yield was not pollination-limited in our study region and that it is currently fairly resilient to single declines of honeybees or wild bumblebees. PMID:28573019

  5. Sensitivity of commercial pumpkin yield to potential decline among different groups of pollinating bees.

    Science.gov (United States)

    Pfister, Sonja C; Eckerter, Philipp W; Schirmel, Jens; Cresswell, James E; Entling, Martin H

    2017-05-01

    The yield of animal-pollinated crops is threatened by bee declines, but its precise sensitivity is poorly known. We therefore determined the yield dependence of Hokkaido pumpkin in Germany on insect pollination by quantifying: (i) the relationship between pollen receipt and fruit set and (ii) the cumulative pollen deposition of each pollinator group. We found that approximately 2500 pollen grains per flower were needed to maximize fruit set. At the measured rates of flower visitation, we estimated that bumblebees (21 visits/flower lifetime, 864 grains/visit) or honeybees (123 visits, 260 grains) could individually achieve maximum crop yield, whereas halictid bees are ineffective (11 visits, 16 grains). The pollinator fauna was capable of delivering 20 times the necessary amount of pollen. We therefore estimate that pumpkin yield was not pollination-limited in our study region and that it is currently fairly resilient to single declines of honeybees or wild bumblebees.

  6. Limitations in Using Chemical Oxidative Potential to Understand Oxidative Stress from Particulate Matter

    Science.gov (United States)

    Chan, A. W. H.; Wang, S.; Wang, X.; Kohl, L.; Chow, C. W.

    2017-12-01

    Particulate matter (PM) in the atmosphere is known to cause adverse cardiorespiratory health effects. It has been suggested that the ability of PM to generate oxidative stress leads to a proinflammatory response. In this work, we study the biological relevance of using a chemical oxidative potential (OP) assay to evaluate proinflammatory response in airway epithelial cells. Here we study the OPs of laboratory secondary organic aerosol (SOA) and metal mixtures, ambient PM from India, ash from the 2016 Alberta wildfires, and diesel exhaust particles. We use SOA derived from naphthalene and from monoterpenes as model systems for SOA. We measure OP using the dithiothreitol (DTT) assay, and cytosolic reactive oxygen species (ROS) production in BEAS-2B cell culture was measured using CellROX assay. We found that both SOA and copper show high OPs individually, but the OP of the combined SOA/copper mixture, which is more atmospherically relevant, was lower than either of the individual OPs. The reduced activity is attributed to chelation between metals and organic compounds using proton nuclear magnetic resonance. There is reasonable association between DTT activity and cellular ROS production within each particle type, but weak association across different particle types, suggesting that particle composition plays an important role in distinguishing between antioxidant consumption and ROS production. Our results highlight that while oxidative potential is a useful metric of PM's ability to generate oxidative stress, the chemical composition and cellular environment should be considered in understanding health impacts of PM.

  7. Nitrate-Dependent Iron Oxidation: A Potential Mars Metabolism

    Science.gov (United States)

    Price, Alex; Pearson, Victoria K.; Schwenzer, Susanne P.; Miot, Jennyfer; Olsson-Francis, Karen

    2018-01-01

    This work considers the hypothetical viability of microbial nitrate-dependent Fe2+ oxidation (NDFO) for supporting simple life in the context of the early Mars environment. This draws on knowledge built up over several decades of remote and in situ observation, as well as recent discoveries that have shaped current understanding of early Mars. Our current understanding is that certain early martian environments fulfill several of the key requirements for microbes with NDFO metabolism. First, abundant Fe2+ has been identified on Mars and provides evidence of an accessible electron donor; evidence of anoxia suggests that abiotic Fe2+ oxidation by molecular oxygen would not have interfered and competed with microbial iron metabolism in these environments. Second, nitrate, which can be used by some iron oxidizing microorganisms as an electron acceptor, has also been confirmed in modern aeolian and ancient sediment deposits on Mars. In addition to redox substrates, reservoirs of both organic and inorganic carbon are available for biosynthesis, and geochemical evidence suggests that lacustrine systems during the hydrologically active Noachian period (4.1–3.7 Ga) match the circumneutral pH requirements of nitrate-dependent iron-oxidizing microorganisms. As well as potentially acting as a primary producer in early martian lakes and fluvial systems, the light-independent nature of NDFO suggests that such microbes could have persisted in sub-surface aquifers long after the desiccation of the surface, provided that adequate carbon and nitrates sources were prevalent. Traces of NDFO microorganisms may be preserved in the rock record by biomineralization and cellular encrustation in zones of high Fe2+ concentrations. These processes could produce morphological biosignatures, preserve distinctive Fe-isotope variation patterns, and enhance preservation of biological organic compounds. Such biosignatures could be detectable by future missions to Mars with appropriate

  8. Nitrate-Dependent Iron Oxidation: A Potential Mars Metabolism

    Directory of Open Access Journals (Sweden)

    Alex Price

    2018-03-01

    Full Text Available This work considers the hypothetical viability of microbial nitrate-dependent Fe2+ oxidation (NDFO for supporting simple life in the context of the early Mars environment. This draws on knowledge built up over several decades of remote and in situ observation, as well as recent discoveries that have shaped current understanding of early Mars. Our current understanding is that certain early martian environments fulfill several of the key requirements for microbes with NDFO metabolism. First, abundant Fe2+ has been identified on Mars and provides evidence of an accessible electron donor; evidence of anoxia suggests that abiotic Fe2+ oxidation by molecular oxygen would not have interfered and competed with microbial iron metabolism in these environments. Second, nitrate, which can be used by some iron oxidizing microorganisms as an electron acceptor, has also been confirmed in modern aeolian and ancient sediment deposits on Mars. In addition to redox substrates, reservoirs of both organic and inorganic carbon are available for biosynthesis, and geochemical evidence suggests that lacustrine systems during the hydrologically active Noachian period (4.1–3.7 Ga match the circumneutral pH requirements of nitrate-dependent iron-oxidizing microorganisms. As well as potentially acting as a primary producer in early martian lakes and fluvial systems, the light-independent nature of NDFO suggests that such microbes could have persisted in sub-surface aquifers long after the desiccation of the surface, provided that adequate carbon and nitrates sources were prevalent. Traces of NDFO microorganisms may be preserved in the rock record by biomineralization and cellular encrustation in zones of high Fe2+ concentrations. These processes could produce morphological biosignatures, preserve distinctive Fe-isotope variation patterns, and enhance preservation of biological organic compounds. Such biosignatures could be detectable by future missions to Mars with

  9. Nitrate-Dependent Iron Oxidation: A Potential Mars Metabolism.

    Science.gov (United States)

    Price, Alex; Pearson, Victoria K; Schwenzer, Susanne P; Miot, Jennyfer; Olsson-Francis, Karen

    2018-01-01

    This work considers the hypothetical viability of microbial nitrate-dependent Fe 2+ oxidation (NDFO) for supporting simple life in the context of the early Mars environment. This draws on knowledge built up over several decades of remote and in situ observation, as well as recent discoveries that have shaped current understanding of early Mars. Our current understanding is that certain early martian environments fulfill several of the key requirements for microbes with NDFO metabolism. First, abundant Fe 2+ has been identified on Mars and provides evidence of an accessible electron donor; evidence of anoxia suggests that abiotic Fe 2+ oxidation by molecular oxygen would not have interfered and competed with microbial iron metabolism in these environments. Second, nitrate, which can be used by some iron oxidizing microorganisms as an electron acceptor, has also been confirmed in modern aeolian and ancient sediment deposits on Mars. In addition to redox substrates, reservoirs of both organic and inorganic carbon are available for biosynthesis, and geochemical evidence suggests that lacustrine systems during the hydrologically active Noachian period (4.1-3.7 Ga) match the circumneutral pH requirements of nitrate-dependent iron-oxidizing microorganisms. As well as potentially acting as a primary producer in early martian lakes and fluvial systems, the light-independent nature of NDFO suggests that such microbes could have persisted in sub-surface aquifers long after the desiccation of the surface, provided that adequate carbon and nitrates sources were prevalent. Traces of NDFO microorganisms may be preserved in the rock record by biomineralization and cellular encrustation in zones of high Fe 2+ concentrations. These processes could produce morphological biosignatures, preserve distinctive Fe-isotope variation patterns, and enhance preservation of biological organic compounds. Such biosignatures could be detectable by future missions to Mars with appropriate

  10. An assessment of irrigation needs and crop yield for the United States under potential climate changes

    Science.gov (United States)

    Brumbelow, Kelly; Georgakakos, Aris P.

    2000-01-01

    Past assessments of climate change on U.S. agriculture have mostly focused on changes in crop yield. Few studies have included the entire conterminous U.S., and few studies have assessed changing irrigation requirements. None have included the effects of changing soil moisture characteristics as determined by changing climatic forcing. This study assesses changes in irrigation requirements and crop yields for five crops in the areas of the U.S. where they have traditionally been grown. Physiologically-based crop models are used to incorporate inputs of climate, soils, agricultural management, and drought stress tolerance. Soil moisture values from a macroscale hydrologic model run under a future climate scenario are used to initialize soil moisture content at the beginning of each growing season. Historical crop yield data is used to calibrate model parameters and determine locally acceptable drought stress as a management parameter. Changes in irrigation demand and crop yield are assessed for both means and extremes by comparing results for atmospheric forcing close to the present climate with those for a future climate scenario. Assessments using the Canadian Center for Climate Modeling and Analysis General Circulation Model (CGCM1) indicate greater irrigation demands in the southern U.S. and decreased irrigation demands in the northern and western U.S. Crop yields typically increase except for winter wheat in the southern U.S. and corn. Variability in both irrigation demands and crop yields increases in most cases. Assessment results for the CGCM1 climate scenario are compared to those for the Hadley Centre for Climate Prediction and Research GCM (HadCM2) scenario for southwestern Georgia. The comparison shows significant differences in irrigation and yield trends, both in magnitude and direction. The differences reflect the high forecast uncertainty of current GCMs. Nonetheless, both GCMs indicate higher variability in future climatic forcing and, consequently

  11. Diagnostic yield of hair and urine toxicology testing in potential child abuse cases.

    Science.gov (United States)

    Stauffer, Stephanie L; Wood, Stephanie M; Krasowski, Matthew D

    2015-07-01

    Detection of drugs in a child may be the first objective finding that can be reported in cases of suspected child abuse. Hair and urine toxicology testing, when performed as part of the initial clinical evaluation for suspected child abuse or maltreatment, may serve to facilitate the identification of at-risk children. Furthermore, significant environmental exposure to a drug (considered by law to constitute child abuse in some states) may be identified by toxicology testing of unwashed hair specimens. In order to determine the clinical utility of hair and urine toxicology testing in this population we performed a retrospective chart review on all children for whom hair toxicology testing was ordered at our academic medical center between January 2004 and April 2014. The medical records of 616 children aged 0-17.5 years were reviewed for injury history, previous medication and illicit drug use by caregiver(s), urine drug screen result (if performed), hair toxicology result, medication list, and outcome of any child abuse evaluation. Hair toxicology testing was positive for at least one compound in 106 cases (17.2%), with unexplained drugs in 82 cases (13.3%). Of these, there were 48 cases in which multiple compounds (including combination of parent drugs and/or metabolites within the same drug class) were identified in the sample of one patient. The compounds most frequently identified in the hair of our study population included cocaine, benzoylecgonine, native (unmetabolized) tetrahydrocannabinol, and methamphetamine. There were 68 instances in which a parent drug was identified in the hair without any of its potential metabolites, suggesting environmental exposure. Among the 82 cases in which hair toxicology testing was positive for unexplained drugs, a change in clinical outcome was noted in 71 cases (86.5%). Urine drug screens (UDS) were performed in 457 of the 616 reviewed cases. Of these, over 95% of positive UDS results could be explained by iatrogenic drug

  12. Reversible Compositional Control of Oxide Surfaces by Electrochemical Potentials

    KAUST Repository

    Mutoro, Eva

    2012-01-05

    Perovskite oxides can exhibit a wide range of interesting characteristics such as being catalytically active and electronically/ionically conducting, and thus, they have been used in a number of solid-state devices such as solid oxide fuel cells (SOFCs) and sensors. As the surface compositions of perovskites can greatly influence the catalytic properties, knowing and controlling their surface compositions is crucial to enhance device performance. In this study, we demonstrate that the surface strontium (Sr) and cobalt (Co) concentrations of perovskite-based thin films can be controlled reversibly at elevated temperatures by applying small electrical potential biases. The surface compositional changes of La 0.8Sr 0.2CoO 3-δ (LSC 113), (La 0.5Sr 0.5) 2CoO 4±δ (LSC 214), and LSC 214-decorated LSC 113 films (LSC 113/214) were investigated in situ by utilizing synchrotron-based X-ray photoelectron spectroscopy (XPS), where the largest changes of surface Sr were found for the LSC 113/214 surface. These findings offer the potential of reversibly controlling the surface functionality of perovskites. © 2011 American Chemical Society.

  13. Dependency of global primary bioenergy crop potentials in 2050 on food systems, yields, biodiversity conservation and political stability

    International Nuclear Information System (INIS)

    Erb, Karl-Heinz; Haberl, Helmut; Plutzar, Christoph

    2012-01-01

    The future bioenergy crop potential depends on (1) changes in the food system (food demand, agricultural technology), (2) political stability and investment security, (3) biodiversity conservation, (4) avoidance of long carbon payback times from deforestation, and (5) energy crop yields. Using a biophysical biomass-balance model, we analyze how these factors affect global primary bioenergy potentials in 2050. The model calculates biomass supply and demand balances for eleven world regions, eleven food categories, seven food crop types and two livestock categories, integrating agricultural forecasts and scenarios with a consistent global land use and NPP database. The TREND scenario results in a global primary bioenergy potential of 77 EJ/yr, alternative assumptions on food-system changes result in a range of 26–141 EJ/yr. Exclusion of areas for biodiversity conservation and inaccessible land in failed states reduces the bioenergy potential by up to 45%. Optimistic assumptions on future energy crop yields increase the potential by up to 48%, while pessimistic assumptions lower the potential by 26%. We conclude that the design of sustainable bioenergy crop production policies needs to resolve difficult trade-offs such as food vs. energy supply, renewable energy vs. biodiversity conservation or yield growth vs. reduction of environmental problems of intensive agriculture. - Highlights: ► Global energy crop potentials in 2050 are calculated with a biophysical biomass-balance model. ► The study is focused on dedicated energy crops, forestry and residues are excluded. ► Depending on food-system change, global energy crop potentials range from 26–141 EJ/yr. ► Exclusion of protected areas and failed states may reduce the potential up to 45%. ► The bioenergy potential may be 26% lower or 45% higher, depending on energy crop yields.

  14. Seed yield response to N fertilization and potential of proximal sensing in Italian ryegrass seed crops

    DEFF Research Database (Denmark)

    Vleugels, Tim; Rijckaert, Georges; Gislum, René

    2017-01-01

    Italian ryegrass (Lolium multiflorum L.) seed crops are often routinely fertilized with a predetermined amount of nitrogen (N) fertilizer in spring. However, nitrate leaching and increasing N fertilizer prices require rationalized fertilizer applications without compromises in seed yield....... The objectives of this study were (1) to determine the seed yield response to N fertilization, and (2) to evaluate if NDVI values can reliably predict the N status in Italian ryegrass seed crops. During eight years, field trials were conducted with two cultivars ‘Melclips’ and ‘Melquatro’, and seven N strategies...... applied after the forage cut as single or split application: 0, 60, 60 + 30, 90, 90 + 30, 120 and 150 kg N ha−1. NDVI values were obtained with a ‘GreenSeeker’ optical sensor. Maximum seed yield was attained at 141 kg N ha−1 total available N (92 kg N ha−1 fertilized). Higher fertilizations only increased...

  15. Modern maize hybrids in Northeast China exhibit increased yield potential and resource use efficiency despite adverse climate change.

    Science.gov (United States)

    Chen, Xiaochao; Chen, Fanjun; Chen, Yanling; Gao, Qiang; Yang, Xiaoli; Yuan, Lixing; Zhang, Fusuo; Mi, Guohua

    2013-03-01

    The impact of global changes on food security is of serious concern. Breeding novel crop cultivars adaptable to climate change is one potential solution, but this approach requires an understanding of complex adaptive traits for climate-change conditions. In this study, plant growth, nitrogen (N) uptake, and yield in relation to climatic resource use efficiency of nine representative maize cultivars released between 1973 and 2000 in China were investigated in a 2-year field experiment under three N applications. The Hybrid-Maize model was used to simulate maize yield potential in the period from 1973 to 2011. During the past four decades, the total thermal time (growing degree days) increased whereas the total precipitation and sunshine hours decreased. This climate change led to a reduction of maize potential yield by an average of 12.9% across different hybrids. However, the potential yield of individual hybrids increased by 118.5 kg ha(-1)  yr(-1) with increasing year of release. From 1973 to 2000, the use efficiency of sunshine hours, thermal time, and precipitation resources increased by 37%, 40%, and 41%, respectively. The late developed hybrids showed less reduction in yield potential in current climate conditions than old cultivars, indicating some adaptation to new conditions. Since the mid-1990s, however, the yield impact of climate change exhibited little change, and even a slight worsening for new cultivars. Modern breeding increased ear fertility and grain-filling rate, and delayed leaf senescence without modification in net photosynthetic rate. The trade-off associated with delayed leaf senescence was decreased grain N concentration rather than increased plant N uptake, therefore N agronomic efficiency increased simultaneously. It is concluded that modern maize hybrids tolerate the climatic changes mainly by constitutively optimizing plant productivity. Maize breeding programs in the future should pay more attention to cope with the limiting

  16. Quantifying the potential for reservoirs to secure future surface water yields in the world’s largest river basins

    Science.gov (United States)

    Liu, Lu; Parkinson, Simon; Gidden, Matthew; Byers, Edward; Satoh, Yusuke; Riahi, Keywan; Forman, Barton

    2018-04-01

    Surface water reservoirs provide us with reliable water supply, hydropower generation, flood control and recreation services. Yet reservoirs also cause flow fragmentation in rivers and lead to flooding of upstream areas, thereby displacing existing land-use activities and ecosystems. Anticipated population growth and development coupled with climate change in many regions of the globe suggests a critical need to assess the potential for future reservoir capacity to help balance rising water demands with long-term water availability. Here, we assess the potential of large-scale reservoirs to provide reliable surface water yields while also considering environmental flows within 235 of the world’s largest river basins. Maps of existing cropland and habitat conservation zones are integrated with spatially-explicit population and urbanization projections from the Shared Socioeconomic Pathways to identify regions unsuitable for increasing water supply by exploiting new reservoir storage. Results show that even when maximizing the global reservoir storage to its potential limit (∼4.3–4.8 times the current capacity), firm yields would only increase by about 50% over current levels. However, there exist large disparities across different basins. The majority of river basins in North America are found to gain relatively little firm yield by increasing storage capacity, whereas basins in Southeast Asia display greater potential for expansion as well as proportional gains in firm yield under multiple uncertainties. Parts of Europe, the United States and South America show relatively low reliability of maintaining current firm yields under future climate change, whereas most of Asia and higher latitude regions display comparatively high reliability. Findings from this study highlight the importance of incorporating different factors, including human development, land-use activities, and climate change, over a time span of multiple decades and across a range of different

  17. Oxidative shift in tissue redox potential increases beat-to-beat variability of action potential duration.

    Science.gov (United States)

    Kistamás, Kornél; Hegyi, Bence; Váczi, Krisztina; Horváth, Balázs; Bányász, Tamás; Magyar, János; Szentandrássy, Norbert; Nánási, Péter P

    2015-07-01

    Profound changes in tissue redox potential occur in the heart under conditions of oxidative stress frequently associated with cardiac arrhythmias. Since beat-to-beat variability (short term variability, SV) of action potential duration (APD) is a good indicator of arrhythmia incidence, the aim of this work was to study the influence of redox changes on SV in isolated canine ventricular cardiomyocytes using a conventional microelectrode technique. The redox potential was shifted toward a reduced state using a reductive cocktail (containing dithiothreitol, glutathione, and ascorbic acid) while oxidative changes were initiated by superfusion with H2O2. Redox effects were evaluated as changes in "relative SV" determined by comparing SV changes with the concomitant APD changes. Exposure of myocytes to the reductive cocktail decreased SV significantly without any detectable effect on APD. Application of H2O2 increased both SV and APD, but the enhancement of SV was the greater, so relative SV increased. Longer exposure to H2O2 resulted in the development of early afterdepolarizations accompanied by tremendously increased SV. Pretreatment with the reductive cocktail prevented both elevation in relative SV and the development of afterdepolarizations. The results suggest that the increased beat-to-beat variability during an oxidative stress contributes to the generation of cardiac arrhythmias.

  18. Effects of climate change on yield potential of wheat and maize crops in the European Union

    NARCIS (Netherlands)

    Wolf, J.; Diepen, van C.A.

    1995-01-01

    Yields of winter wheat, silage maize and grain maize in the main arable areas of the European Union (EU) were calculated with a simulation model, WOFOST, using historical weather data and average soil characteristics. The sensitivity of the model to individual weather variables was determined.

  19. Potential of commodity chemicals to become bio-based according to maximum yields and petrochemical prices

    NARCIS (Netherlands)

    Straathof, Adrie J.J.; Bampouli, A.

    2017-01-01

    Carbohydrates are the prevailing biomass components available for bio-based production. The most direct way to convert carbohydrates into commodity chemicals is by one-step conversion at maximum theoretical yield, such as by anaerobic fermentation without side product formation. Considering these

  20. Calculated ionisation potentials determine the oxidation of vanillin precursors by lignin peroxidase.

    Science.gov (United States)

    ten Have, R; Rietjens, I M; Hartmans, S; Swarts, H J; Field, J A

    1998-07-03

    In view of the biocatalytic production of vanillin, this research focused on the lignin peroxidase (LiP) catalysed oxidation of naturally occurring phenolic derivatives: O-methyl ethers, O-acetyl esters, and O-glucosyl ethers. The ionisation potential (IP) of a series of model compounds was calculated and compared to their experimental conversion by LiP, defining a relative IP threshold of approximately 9.0 eV. Based on this threshold value only the O-acetyl esters and glucosides of isoeugenol and coniferyl alcohol would be potential LiP substrates. Both O-acetyl esters were tested and were shown to be converted to O-acetyl vanillin in molar yields of 51.8 and 2.3%, respectively.

  1. Oxidative Damage and Mutagenic Potency of Fast Neutron and UV-B Radiation in Pollen Mother Cells and Seed Yield of Vicia faba L.

    Directory of Open Access Journals (Sweden)

    Ekram Abdel Haliem

    2013-01-01

    Full Text Available In recent years, there has been a great deal of attention toward free radicals, reactive oxygen species (ROS generated by exposure of crop plant cells to physical radiations. Henceforth, the current study was planned to compare oxidative stress and mutagenic potential of different irradiation doses of fast neutron (FN and UV-B on meiotic-pollen mother cells (PMCs, pollen grains (PGs and seeds yielded from irradiated faba beans seedlings. On the cytogenetic level, each irradiation type had special interference with DNA of PMC and exhibited wide range of mutagenic action on the frequency and type of chromosomal anomalies, fertility of PGs and seed yield productivity based on the irradiation exposure dose and radiation sensitivity of faba bean plants compared with un-irradiated ones. On the molecular level, SDS-PAGE and RPAD-PCR analyses of seeds yielded from irradiated seedlings exhibited distinctive polymorphisms based on size, intensity, appearance, and disappearance of polypeptides bands compared with un-irradiated ones. The total values of protein and DNA polymorphisms reached 88% and 90.80% respectively. The neutron fluency (2.3 × 106 n/cm2 and UV-B dose for 1 hr were recorded as bio-positive effects. The present study proved that genetic variations revealed by cytogenetic test could be supported by gene expression (alterations in RAPD and protein profiles.

  2. Genetic potential and heritability estimates of yield traits in F3 segregating populations of bread wheat

    Directory of Open Access Journals (Sweden)

    Soshma Jan

    2015-06-01

    Full Text Available An experiment comprising of 24 wheat genotypes was undertaken during 2011-12, at New Developmental Research Farm, The University of Agriculture Peshawar, to elucidate information on the nature and magnitude of genetic variability, index of transmissibility and assessing the level of genetic improvement of the quantitative characters. The experimental material comprising 19 F3 populations along with their 5 parents of bread wheat were evaluated in randomized complete block design (RCBD with three replications. Analysis of variance exhibited highly significant (P ≤ 0.01 differences among genotypes for all the traits studied. F3 population Ghaznavi-98 x Pirsabak-05 showed maximum mean value for 1000-grain weight (47.3 g and biological yield (11474.9 kg ha-1, whereas, maximum values for grain yield (4027.3 kg ha-1, and harvest index (48.1% were observed for Pirsabak-05 x AUP-4006. Moreover, maximum spike length (11 cm was recorded for cross combination Pirsabak-05 x Pirsabak-04 and Janbaz x Pirsabak-05, respectively. In addition, Pirsabak-04 showed maximum value for number of grains spike-1 (55.0. Genetic variances were of greater magnitude than environmental variances for all the traits except for spike length and 1000-grain weight. Heritability estimates were of higher magnitude ranged from 0.64 to 0.92 for harvest index, biological yield, grain yield, and grains spike-1. Moderate to low heritability (0.40-0.46 was observed for 1000-grain weight, and spike length, respectively. Genetic gain was for spike length (0.48 cm, grains spike-1 (8.57, 1000-grain weight (2.93 g, grain yield (639.87 kg ha-1, biological yield (1790.03 kg ha-1, and harvest index (5.32 %. From high values of heritability and genetic advance, it could be concluded that selection for traits like grains spike-1 suggested good selection criteria and could be effective for future breeding programs. DOI: http://dx.doi.org/10.3126/ije.v4i2.12630 International Journal of Environment

  3. Oxidative Stress in COPD: Sources, Markers, and Potential Mechanisms

    Directory of Open Access Journals (Sweden)

    Adam John Anthony McGuinness

    2017-02-01

    Full Text Available Markers of oxidative stress are increased in chronic obstructive pulmonary disease (COPD and reactive oxygen species (ROS are able to alter biological molecules, signaling pathways and antioxidant molecule function, many of which have been implicated in the pathogenesis of COPD. However, the involvement of ROS in the development and progression of COPD is not proven. Here, we discuss the sources of ROS, and the defences that have evolved to protect against their harmful effects. We address the role that ROS may have in the development and progression of COPD, as well as current therapeutic attempts at limiting the damage they cause. Evidence has indicated that the function of several key cells appears altered in COPD patients, and expression levels of important oxidant and antioxidant molecules may be abnormal. Therapeutic trials attempting to restore equilibrium to these molecules have not impacted upon all facets of disease and whilst the theory behind ROS influence in COPD appears sound, current models testing relevant pathways to tissue damage are limited. The heterogeneity seen in COPD patients presents a challenge to our understanding, and further research is essential to identify potential targets and stratified COPD patient populations where ROS therapies may be maximally efficacious.

  4. Dependency of global primary bioenergy crop potentials in 2050 on food systems, yields, biodiversity conservation and political stability.

    Science.gov (United States)

    Erb, Karl-Heinz; Haberl, Helmut; Plutzar, Christoph

    2012-08-01

    The future bioenergy crop potential depends on (1) changes in the food system (food demand, agricultural technology), (2) political stability and investment security, (3) biodiversity conservation, (4) avoidance of long carbon payback times from deforestation, and (5) energy crop yields. Using a biophysical biomass-balance model, we analyze how these factors affect global primary bioenergy potentials in 2050. The model calculates biomass supply and demand balances for eleven world regions, eleven food categories, seven food crop types and two livestock categories, integrating agricultural forecasts and scenarios with a consistent global land use and NPP database. The TREND scenario results in a global primary bioenergy potential of 77 EJ/yr, alternative assumptions on food-system changes result in a range of 26-141 EJ/yr. Exclusion of areas for biodiversity conservation and inaccessible land in failed states reduces the bioenergy potential by up to 45%. Optimistic assumptions on future energy crop yields increase the potential by up to 48%, while pessimistic assumptions lower the potential by 26%. We conclude that the design of sustainable bioenergy crop production policies needs to resolve difficult trade-offs such as food vs. energy supply, renewable energy vs. biodiversity conservation or yield growth vs. reduction of environmental problems of intensive agriculture.

  5. Biomass and biomass and biogas yielding potential of sorghum as affected by planting density, sowing time and cultivar

    International Nuclear Information System (INIS)

    Mahmood, A.; Hussain, A.; Shahzad, A. N.; Honermeier, B.

    2015-01-01

    Biogas from biomass is a promising renewable energy source whose importance is increasing in European as well as in other countries. A field experiment at one location (Experimental Station Giessen, Justus Liebig University of Giessen, Germany) over two years was designed to study the effect of altering sowing time (ST), planting density and cultivar on the biomass yield and chemical composition of biomass sorghum, and its potential for methane production. Of the two cultivars tested, cv. Goliath (intraspecific hybrid) was more productive with respect to biomass yield than cv. Bovital (S. bicolor x S. sudanense hybrid). ST also influenced biomass yield and most of the quality parameters measured. Delayed sowing was in general advantageous. The choice of cultivar had a marked effect on biogas and methane yield. The highest biogas and methane yields were produced by late sown cv. Bovital. Sub-optimal planting densities limited biomass accumulation of the crop, however neither the chemical composition nor the methane yield was affected by planting density. (author)

  6. Catalytic oxidative conversion of cellulosic biomass to formic acid and acetic acid with exceptionally high yields

    KAUST Repository

    Zhang, Jizhe

    2014-09-01

    Direct conversion of raw biomass materials to fine chemicals is of great significance from both economic and ecological perspectives. In this paper, we report that a Keggin-type vanadium-substituted phosphomolybdic acid catalyst, namely H4PVMo11O40, is capable of converting various biomass-derived substrates to formic acid and acetic acid with high selectivity in a water medium and oxygen atmosphere. Under optimized reaction conditions, H4PVMo11O40 gave an exceptionally high yield of formic acid (67.8%) from cellulose, far exceeding the values achieved in previous catalytic systems. Our study demonstrates that heteropoly acids are generally effective catalysts for biomass conversion due to their strong acidities, whereas the composition of metal addenda atoms in the catalysts has crucial influence on the reaction pathway and the product selectivity. © 2013 Elsevier B.V.

  7. Biochar potential in intensive cultivation of Capsicum annuum L. (sweet pepper): crop yield and plant protection.

    Science.gov (United States)

    Kumar, Abhay; Elad, Yigal; Tsechansky, Ludmila; Abrol, Vikas; Lew, Beni; Offenbach, Rivka; Graber, Ellen R

    2018-01-01

    The influence of various biochars on crop yield and disease resistance of Capsicum annuum L. (sweet pepper) under modern, high input, intensive net house cultivation was tested over the course of 2011-2014 in the Arava desert region of Israel. A pot experiment with Lactuca sativa L. (lettuce) grown in the absence of fertilizer employed the 3-year-old field trial soils to determine if biochar treatments contributed to soil intrinsic fertility. Biochar amendments resulted in a significant increase in the number and weight of pepper fruits over 3 years. Concomitant with the increased yield, biochar significantly decreased the severity of powdery mildew (Leveillula taurica) disease and broad mite (Polyphagotarsonemus latus) pest infestation. Biochar additions resulted in increased soil organic matter but did not influence the pH, electrical conductivity or soil or plant mineral nutrients. Intrinsic fertility experiments with lettuce showed that two of the four biochar-treated field soils had significant positive impacts on lettuce fresh weight and total chlorophyll, carotenoid and anthocyanin contents. Biochar-based soil management can enhance the functioning of intensive, commercial, net house production of peppers under the tested conditions, resulting in increased crop yield and plant resistance to disease over several years. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  8. Land Use, Yield and Quality Changes of Minor Field Crops: Is There Superseded Potential to Be Reinvented in Northern Europe?

    Science.gov (United States)

    Peltonen-Sainio, Pirjo; Jauhiainen, Lauri; Lehtonen, Heikki

    2016-01-01

    Diversification of agriculture was one of the strengthened aims of the greening payment of European Agricultural Policy (CAP) as diversification provides numerous ecosystems services compared to cereal-intensive crop rotations. This study focuses on current minor crops in Finland that have potential for expanded production and considers changes in their cropping areas, yield trends, breeding gains, roles in crop rotations and potential for improving resilience. Long-term datasets of Natural Resources Institute Finland and farmers' land use data from the Agency of Rural Affairs were used to analyze the above-mentioned trends and changes. The role of minor crops in rotations declined when early and late CAP periods were compared and that of cereal monocultures strengthened. Genetic yield potentials of minor crops have increased as also genetic improvements in quality traits, although some typical trade-offs with improved yields have also appeared. However, the gap between potential and attained yields has expanded, depending on the minor crop, as national yield trends have either stagnated or declined. When comparing genetic improvements of minor crops to those of the emerging major crop, spring wheat, breeding achievements in minor crops were lower. It was evident that the current agricultural policies in the prevailing market and the price environment have not encouraged cultivation of minor crops but further strengthened the role of cereal monocultures. We suggest optimization of agricultural land use, which is a core element of sustainable intensification, as a future means to couple long-term environmental sustainability with better success in economic profitability and social acceptability. This calls for development of effective policy instruments to support farmer's diversification actions.

  9. Biochemical methane potential, biodegradability, alkali treatment and influence of chemical composition on methane yield of yard wastes.

    Science.gov (United States)

    Gunaseelan, Victor Nallathambi

    2016-03-01

    In this study, the biochemical CH4 potential, rate, biodegradability, NaOH treatment and the influence of chemical composition on CH4 yield of yard wastes generated from seven trees were examined. All the plant parts were sampled for their chemical composition and subjected to the biochemical CH4 potential assay. The component parts exhibited significant variation in biochemical CH4 potential, which was reflected in their ultimate CH4 yields that ranged from 109 to 382 ml g(-1) volatile solids added and their rate constants that ranged from 0.042 to 0.173 d(-1). The biodegradability of the yard wastes ranged from 0.26 to 0.86. Variation in the biochemical CH4 potential of the yard wastes could be attributed to variation in the chemical composition of the different fractions. In the Thespesia yellow withered leaf, Tamarindus fruit pericarp and Albizia pod husk, NaOH treatment enhanced the ultimate CH4 yields by 17%, 77% and 63%, respectively, and biodegradability by 15%, 77% and 61%, respectively, compared with the untreated samples. The effectiveness of NaOH treatment varied for different yard wastes, depending on the amounts of acid detergent fibre content. Gliricidia petals, Prosopis leaf, inflorescence and immature pod, Tamarindus seeds, Albizia seeds, Cassia seeds and Delonix seeds exhibited CH4 yields higher than 300 ml g(-1) volatile solids added. Multiple linear regression models for predicting the ultimate CH4 yield and biodegradability of yard wastes were designed from the results of this work. © The Author(s) 2016.

  10. Expressão do potencial de rendimento de cultivares de soja Yield potential expression of soybean genotypes

    Directory of Open Access Journals (Sweden)

    Hugo Motta Navarro Júnior

    2002-03-01

    Full Text Available A soja possui alto potencial de rendimento de grãos, mas em virtude da interação genótipo vs. ambiente esse potencial não é verificado em sua totalidade. Utilizando-se seis genótipos de soja de diferentes ciclos, objetivou-se estudar a expressão do potencial de rendimento de grãos e quantificá-lo durante a ontogenia. O experimento foi conduzido no ano agrícola 1996/97 na Estação Experimental Agronômica da Universidade Federal do Rio Grande do Sul, Eldorado do Sul, RS. As avaliações foram realizadas em plantas individuais e se estenderam desde o estádio de floração até o de maturação. Os resultados obtidos indicam que alto potencial de rendimento não necessariamente identifica uma planta eficiente na retenção das estruturas reprodutivas. Os potenciais de rendimento estimados na floração e no início do enchimento de grãos não se mantêm até a maturação. Genótipos com alto potencial de rendimento de grãos em R8 não apresentam os maiores potenciais de rendimento de grãos em R2 e em R5, porém, são os que apresentam as menores diferenças entre o potencial estimado em R5 e o estimado em R2.Soybean has high yield potential, which is not totally expressed due to genotype vs. environment interaction. Six soybean genotypes of different maturity groups were used with the objective of studying their yield potential expression and quantifying it during ontogeny. The experiment was conducted during the 1996/97 growing season in the Agronomic Experimental Station of the Universidade Federal do Rio Grande do Sul, Eldorado do Sul, RS, Brazil. Plants were evaluated individually from flowering until maturity. Results obtained indicate that high yield potential does not necessarily mean an efficient plant in reproductive structure retention. Yield potential estimated in the flowering and beginning of grain filling stages are not maintained until maturity. Genotypes with high yield potential in the R8 stage do not present the

  11. Potential design modifications for the High Yield Lithium Injection Fusion Energy (HYLIFE) reaction chamber

    International Nuclear Information System (INIS)

    Pitts, J.H.; Hovingh, J.; Meier, W.R.; Monsler, M.J.; Powell, E.G.; Walker, P.E.

    1979-01-01

    Generation of electric power from inertial confinement fusion requires a reaction chamber. One promising type, the High Yield Lithium Injection Fusion Energy (HYLIFE) chamber, includes a falling array of liquid lithium jets. These jets act as: (1) a renewable first wall and blanket to shield metal components from x-ray and neutron exposure, (2) a tritium breeder to replace tritium burned during the fusion process, and (3) an absorber and transfer medium for fusion energy. Over 90% of the energy produced in the reaction chamber is absorbed in the lithium jet fall. Design aspects are included

  12. Nasogastric feeding tubes from a neonatal department yield high concentrations of potentially pathogenic bacteria- even 1 d after insertion

    DEFF Research Database (Denmark)

    Meinich Petersen, Sandra; Greisen, Gorm; Krogfelt, Karen Angeliki

    2016-01-01

    probiotic administration through the tube. RESULTS: Out of the 94 NG-tubes, 89% yielded more than 1,000 colony-forming units (CFU)/ml bacteria, and 55% yielded the potentially pathogenic Enterobacteriaceae and/or Staphylococcus aureus. The mean concentration in the yield was 5.3 (SD: 2.1, maximum 9.4) log10......BACKGROUND: Preterm infants are vulnerable to pathogens and at risk of developing necrotizing enterocolitis (NEC) or sepsis. Nasogastric feeding tubes (NG-tubes) might contaminate feeds given through them due to biofilm formation. We wanted to determine if there is a rationale in replacing NG......-tubes more often to reduce contamination. METHODS: We conducted an observational study of used NG-tubes from a tertiary neonatal department. After removal, we flushed a 1-ml saline solution through the tube, determined the density of bacteria by culture, and related it to the duration of use and any...

  13. 1,4-Diamino-2-butanone, a wide-spectrum microbicide, yields reactive species by metal-catalyzed oxidation.

    Science.gov (United States)

    Soares, Chrislaine O; Alves, Maria Julia M; Bechara, Etelvino J H

    2011-06-15

    The α-aminoketone 1,4-diamino-2-butanone (DAB), a putrescine analogue, is highly toxic to various microorganisms, including Trypanosoma cruzi. However, little is known about the molecular mechanisms underlying DAB's cytotoxic properties. We report here that DAB (pK(a) 7.5 and 9.5) undergoes aerobic oxidation in phosphate buffer, pH 7.4, at 37°C, catalyzed by Fe(II) and Cu(II) ions yielding NH(4)(+) ion, H(2)O(2), and 4-amino-2-oxobutanal (oxoDAB). OxoDAB, like methylglyoxal and other α-oxoaldehydes, is expected to cause protein aggregation and nucleobase lesions. Propagation of DAB oxidation by superoxide radical was confirmed by the inhibitory effect of added SOD (50 U ml-1) and stimulatory effect of xanthine/xanthine oxidase, a source of superoxide radical. EPR spin trapping studies with 5,5-dimethyl-1-pyrroline-1-oxide (DMPO) revealed an adduct attributable to DMPO-HO(•), and those with α-(4-pyridyl-1-oxide)-N-tert-butylnitrone or 3,5-dibromo-4-nitrosobenzenesulfonic acid, a six-line adduct assignable to a DAB(•) resonant enoyl radical adduct. Added horse spleen ferritin (HoSF) and bovine apo-transferrin underwent oxidative changes in tryptophan residues in the presence of 1.0-10 mM DAB. Iron release from HoSF was observed as well. Assays performed with fluorescein-encapsulated liposomes of cardiolipin and phosphatidylcholine (20:80) incubated with DAB resulted in extensive lipid peroxidation and consequent vesicle permeabilization. DAB (0-10 mM) administration to cultured LLC-MK2 epithelial cells caused a decline in cell viability, which was inhibited by preaddition of either catalase (4.5 μM) or aminoguanidine (25 mM). Our findings support the hypothesis that DAB toxicity to several pathogenic microorganisms previously described may involve not only reported inhibition of polyamine metabolism but also DAB pro-oxidant activity. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Sclerotial biomass and carotenoid yield of Penicillium sp. PT95 under oxidative growth conditions and in the presence of antioxidant ascorbic acid.

    Science.gov (United States)

    Li, X L; Cui, X H; Han, J R

    2006-09-01

    To determine the effect of oxidative stress and exogenous ascorbic acid on sclerotial biomass and carotenoid yield of Penicillium sp. PT95. In this experiment, high oxidative stress was applied by the inclusion of FeSO(4) in the growth medium and exposure to light. Low oxidative stress was applied by omitting iron from the growth medium and by incubation in the dark. Supplementation of exogenous ascorbic acid (as antioxidant) to the basal medium caused a concentration-dependent delay of sclerotial differentiation (up to 48 h), decrease of sclerotial biomass (up to 40%) and reduction of carotenoid yield (up to 91%). On the contrary, the exogenous ascorbic acid also caused a concentration-dependent decrease of lipid peroxidation in colonies of this fungus. Under high oxidative stress growth condition, the sclerotial biomass and carotenoid yield of PT95 strain in each plate culture reached 305 mg and 32.94 microg, which were 1.23 and 3.71 times higher, respectively, than those at low oxidative stress growth condition. These data prompted us to consider that in order to attain higher sclerotial biomass and pigment yield, the strain PT95 should be grown under high oxidative stress and in the absence of antioxidants. These results suggest that strain PT95 may be used for solid-state fermentation of carotenoid production under high oxidative stress growth conditions.

  15. Nitric oxide as a potential biomarker in inflammatory bowel disease

    Directory of Open Access Journals (Sweden)

    Nesina Avdagić

    2013-02-01

    Full Text Available The aim of this study was to investigate changes in serum nitric oxide (NO concentration in inflammatory bowel diseases (IBD patients and its use as potential biomarker in differential diagnosis of ulcerative colitis (UC and Crohn's disease (CD and in disease activity assessment. In 60 patients of both genders - 30 with ulcerative colitis and 30 with Crohn's disease - and 30 controls serum nitric oxide concentration was determined by measuring nitrite concentration, a stable metabolic product of NO with oxygen. Conversion of nitrates (NO3- to nitrites (NO2- was done with elementary zinc. The nitrite concentration was determined by classic colorimetrical Griess reaction. Median serum NO concentration was statistically different (p=0,0005 between UC patients (15.25 µmol/L; 13.47 - 19.88 µmol/L, CD patients (14.54 µmol/L; 13.03 -16.32 µmol/L and healthy controls (13.29 µmol/L; 12.40 - 13.92 µmol/L. When active UC and CD patients were compared with inactive UC and CD patients respectively a significant difference in serum NO level was found (p=0.0005. With a cut-off level of 17.39 µmol/L NO had a sensitivity of 100% and a specificity of 100% in discriminating between active and inactive UC patients. With cut-off value of 14.01 µmol/L serum NO level had a sensitivity of 88% and a specificity of 69% in distinguishing between patients with active CD and inactive CD. Serum NO concentration is a minimally invasive and rapid tool for discriminating between active and inactive IBD patients and could be used as useful biomarker in monitoring of disease activity in IBD patients.

  16. Measurements of acetone yields from the OH-initiated oxidation of terpenes by proton-transfer-reaction mass spectrometry

    International Nuclear Information System (INIS)

    Wisthaler, A.; Lindinger, W.; Jensen, N.R.; Winterhalter, R.; Hjorth, J.

    2002-01-01

    Biogenic VOCs (Volatile Organic Compounds) are known to be emitted in large quantities from vegetation exceeding largely global emissions of anthropogenic VOCs. Monoterpenes (C 10 H 16 ) are important constituents of biogenic VOC emissions. The atmospheric oxidation of Monoterpenes appears to be a potentially relevant source of acetone in the atmosphere. Acetone is present as a significant trace gas in the whole troposphere and influences in particular the atmospheric chemistry in the upper troposphere by substantially contributing to the formation of HO x radicals and peroxyacetyl nitrate (PAN). Acetone is formed promptly, following attack by the OH-radical on the terpene, via a series of highly unstable radical intermediates, but it is also formed slowly via the degradation of stable non-radical intermediates such as pinonaldehyde and nopinone. In order to investigate the relative importance of these processes, the OH-initiated oxidation of α-pinene and β-pinene was investigated in a chamber study, where the concentrations of monoterpenes, acetone, pinonaldehyde and nopinone were monitored by proton-transfer-reaction mass spectrometry (PTR-MS). It was found that significant amounts of acetone are formed directly, whenα-pinene and β-pinene are oxidized by the OH radical, but also secondary chemistry (degradation of primary reaction products) gives a significant contribution to the formation of acetone from monoterpenes. It can be concluded that atmospheric oxidation of monoterpenes contributes a significant fraction to the global acetone source strength. (nevyjel)

  17. Energy Yield Potential Estimation Using Marine Current Turbine Simulations for the Bosphorus

    DEFF Research Database (Denmark)

    Yazicioglu, Hasan; Tunc, K. M. Murat; Ozbek, Muammer

    2017-01-01

    . The differences in elevation and salinity ratios between these two seas cause strong underwater currents. Depending on the morphology of the canal the speed of the flow varies and at some specific locations the energy intensity reaches to sufficient levels where electricity generation by marine current turbines...... becomes economically feasible. In this study, several simulations are performed for a 10 MW marine turbine farm/ cluster whose location is selected by taking into account several factors such as the canal morphology, current speed and passage of vessels. 360 different simulations are performed for 15...... within the selected region, the analyses are performed for three different flow speeds corresponding to 10 % increase and decrease in the average value. For each simulation the annual energy yield and cluster efficiency are calculated....

  18. A Piston-Rotaxane with Two Potential Stripes: Force Transitions and Yield Stresses

    Directory of Open Access Journals (Sweden)

    Edith M. Sevick

    2013-10-01

    Full Text Available We examine a rod piston-rotaxane system, where the positions of several mobile rings on the axle are controlled by an external force acting on one of the rings. This allows us to access the translational entropy of the rings. For a simple rotaxane molecule with an axle that has uniform ring-axle interactions along its length, the molecule behaves like a miniature piston filled with a one-dimensional ideal gas. We then examine the effect of two stripes on the axle, having different ring-axle interactions with the mobile rings, so that one section is of high energy (repulsive for the rings and another section is of lower energy (or attractive. This kind of rotaxane can exhibit rapid changes in displacement or force, and in particular, this molecule can exhibit a yield stress in which the piston suddenly compresses under a small increase in the applied force.

  19. Shifts in North Sea forage fish productivity and potential fisheries yield

    DEFF Research Database (Denmark)

    Worsøe Clausen, Lotte; Rindorf, Anna; van Deurs, Mikael

    2018-01-01

    productivity. Furthermore, from an ecosystem-based fisheries management perspective, a link between functional complementarity and productivity, indicates that ecosystem resilience may decline with productivity. Based on this, we advise that system productivity, perhaps monitored as forage fish growth, becomes......1. Forage fish populations support large scale fisheries and are key components of marine ecosystems across the world, linking secondary production to higher trophic levels. While climate-induced changes in the North Sea zooplankton community are described and documented in literature......, the associated bottom-up effects and consequences for fisheries remain largely unidentified. 2. We investigated the temporal development in forage fish productivity and the associated influence on fisheries yield of herring, sprat, Norway pout and sandeel in the North Sea. Using principal component analysis, we...

  20. Oxidative Potential of ambient particulate matter in Athens, Greece.

    Science.gov (United States)

    Paraskevopoulou, Despina; Bougiatioti, Aikaterini; Fang, Ting; Liakakou, Eleni; Weber, Rodney; Nenes, Athanasios; Mihalopoulos, Nikolaos

    2017-04-01

    Exposure of populations to airborne particulate matter (PM) is a leading cause of premature death worldwide. Oxidative stress resulting from exposure of chemical species present in PM is a mechanism thought to cause adverse health effects. Apart from radicals present in aerosol, species that can catalytically deplete the antioxidant buffering capacity of cells, called Oxidative Potential (OP), are thought to be particularly toxic. The variability of OP over location, particle age, source and environmental conditions is virtually unknown for most populated regions of the world. Motivated by this, we have built and deployed one of the first operational measurements of OP in Europe at the National Observatory of Athens site in downtown Athens, Greece. OP for fine and coarse mode is measured using a semi-automated dithiothreitol (DTT) assay developed at the Georgia Institute of Technology; the assay measures the oxidation rate of DTT by water-soluble aerosol constituents, and simulates the rate at which the same compounds would deplete antioxidants in-vivo. The DTT oxidation rate per unit volume of air (water-soluble "DTT activity") and aerosol size class (fine, coarse) are used as a measure of aerosol toxicity. We present continuous (24hr average) OP measurements in downtown Athens from July 2016 to January 2017, conducted through quartz fiber filter analysis. The dataset covers a broad range of aerosol sources (pollution from Europe, regional and local biomass burning, dust, marine aerosol, biogenic aerosol) and meteorological conditions. The daily water-soluble DTT activity ranges between 0.02-0.81 nmolmin-1 m-3 (averaging at 0.24 nmolmin-1 m-3) for fine aerosol and between 0.01-0.52 nmolmin-1 m-3 (averaging at 0.08 nmolmin-1 m-3) for coarse particulate matter, indicating that water-soluble fine mode aerosol components possess a significant fraction of the OP. The seasonal variability demonstrates a higher DTT activity during the coldest period of the year for both

  1. A GIS-based model of potential groundwater yield zonation for a sandstone aquifer in the Juye Coalfield, Shangdong, China

    Science.gov (United States)

    Yin, Huiyong; Shi, Yongli; Niu, Huigong; Xie, Daolei; Wei, Jiuchuan; Lefticariu, Liliana; Xu, Shuanxiang

    2018-02-01

    Resolving the potential groundwater yield zonation of sandstone aquifers occurring at depths of several hundred meters has been an important and challenging objective of the hydrogeological research focused on preventing flood hazards in coal mines. Using accessible geological exploration data we put forward a method of predicting the spatial distribution of groundwater storage potential in sandstone aquifers from Permian-age coal deposits in Juye Coalfield, Shangdong, China. A Geological, Tectonic and Lithological Composition Index (GTLCI) model was created using the following parameters: sandstone depth and thickness, faults length density (FaLD), faults density (FaD), fault frequency density (FaFD), fault scale density (FaSD), variation coefficient of the slope (VCS) of the coal seam, intensity index of folds in horizontal direction (IIFoH), and lithological composition index (LCI). Each of these factors was subsequently divided into 5 classes. The analytic hierarchy process (AHP) and trapezoidal fuzzy number (TFN) method was applied to calculate the weight of the conditioning factor and their respective sub-classes. Groundwater yield potential contour map, which was initially constructed using the GTLCI values revealed four groundwater abundance zones. The map was further refined by taking into account hydrogeologic data collected during mining activities. The GTLCI model predictive success rate of 80% was explained by the limited number of boreholes available for validation. It is considered that the GTLCI model is effective at predicting zonation of groundwater yield in the sandstone aquifers from Permian- age coal deposits in Juye Coalfield, China.

  2. The indirect global warming potential and global temperature change potential due to methane oxidation

    International Nuclear Information System (INIS)

    Boucher, Olivier; Collins, Bill; Friedlingstein, Pierre; Shine, Keith P

    2009-01-01

    Methane is the second most important anthropogenic greenhouse gas in the atmosphere next to carbon dioxide. Its global warming potential (GWP) for a time horizon of 100 years is 25, which makes it an attractive target for climate mitigation policies. Although the methane GWP traditionally includes the methane indirect effects on the concentrations of ozone and stratospheric water vapour, it does not take into account the production of carbon dioxide from methane oxidation. We argue here that this CO 2 -induced effect should be included for fossil sources of methane, which results in slightly larger GWP values for all time horizons. If the global temperature change potential is used as an alternative climate metric, then the impact of the CO 2 -induced effect is proportionally much larger. We also discuss what the correction term should be for methane from anthropogenic biogenic sources.

  3. Zeta potentials in the flotation of oxide and silicate minerals.

    Science.gov (United States)

    Fuerstenau, D W; Pradip

    2005-06-30

    Adsorption of collectors and modifying reagents in the flotation of oxide and silicate minerals is controlled by the electrical double layer at the mineral-water interface. In systems where the collector is physically adsorbed, flotation with anionic or cationic collectors depends on the mineral surface being charged oppositely. Adjusting the pH of the system can enhance or prevent the flotation of a mineral. Thus, the point of zero charge (PZC) of the mineral is the most important property of a mineral in such systems. The length of the hydrocarbon chain of the collector is important because of chain-chain association enhances the adsorption once the surfactant ions aggregate to form hemimicelles at the surface. Strongly chemisorbing collectors are able to induce flotation even when collector and the mineral surface are charged similarly, but raising the pH sufficiently above the PZC can repel chemisorbing collectors from the mineral surface. Zeta potentials can be used to delineate interfacial phenomena in these various systems.

  4. Determination of Dacarbazine Φ-Order Photokinetics, Quantum Yields, and Potential for Actinometry.

    Science.gov (United States)

    Maafi, Mounir; Lee, Lok-Yan

    2015-10-01

    The characterization of drugs' photodegradation kinetics is more accurately achieved by means of the recently developed Φ-order kinetics than by the zero-, first-, and/or second-order classical treatments. The photodegradation of anti-cancer dacarbazine (DBZ) in ethanol has been investigated and found to obey Φ-order kinetics when subjected to continuous and monochromatic irradiation of various wavelengths. Its photochemical efficiency was proven to be wavelength dependent in the 220-350 nm range, undergoing a 50-fold increase. Albeit this variation was well defined by a sigmoid pattern, the overall photoreactivity of DBZ was proven to depend also on the contributions of reactants and experimental attributes. The usefulness of DBZ to serve as a drug-actinometer has been investigated using the mathematical framework of Φ-order kinetics. It has been shown that DBZ in ethanol can represent a good candidate for reliable actinometry in the range 270-350 nm. A detailed and easy-to-implement procedure has been proposed for DBZ actinometry. This procedure could advantageously be implemented prior to the determination of the photodegradation quantum yields. This approach might be found useful for the development of many drug actinometers as alternatives to quinine hydrochloride. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  5. The potential of medium-pore zeolites for improved propene yields from catalytic cracking

    Energy Technology Data Exchange (ETDEWEB)

    Bager, F.; Salas, N.; Ernst, S. [Technische Univ. Kaiserslautern (Germany). Dept. of Chemistry, Chemical Technology

    2011-07-01

    The medium-pore zeolites ZSM-5 (MFI), ZSM-22 (TON), ZSM-23 (MTT), and EU-1 (EUO) were synthesized under hydrothermal conditions and modified by ion exchange to obtain the Broensted-acid forms. The activity and selectivity of these catalysts in catalytic cracking of a model compound, viz. n-octane, was studied in a fixed-bed flow-type reactor. The catalytic results clearly reflect the differences in the pore architectures of the tested zeolites on n-octane conversion and on the product selectivities. Over the zeolites with one-dimensional pore systems and without large intracrystalline cavities, a remarkable increase of the contribution of the monomolecular cracking mechanism could be observed as compared to the standard catalyst zeolite ZSM-5. This is indicated by a high selectivity for unsaturated products and, hence, increasing yields of propene. Large cavities in the pore system, viz. in the case of zeolite EU-1, increase the conversion in particular at lower temperatures. However, the large cavities also favor the formation of large transition states required for the classical bimolecular cracking mechanism, resulting in decreased selectivities for unsaturated products, increased selectivities for aromatics formation and faster deactivation. (orig.)

  6. Kinetic determinations of accurate relative oxidation potentials of amines with reactive radical cations.

    Science.gov (United States)

    Gould, Ian R; Wosinska, Zofia M; Farid, Samir

    2006-01-01

    Accurate oxidation potentials for organic compounds are critical for the evaluation of thermodynamic and kinetic properties of their radical cations. Except when using a specialized apparatus, electrochemical oxidation of molecules with reactive radical cations is usually an irreversible process, providing peak potentials, E(p), rather than thermodynamically meaningful oxidation potentials, E(ox). In a previous study on amines with radical cations that underwent rapid decarboxylation, we estimated E(ox) by correcting the E(p) from cyclic voltammetry with rate constants for decarboxylation obtained using laser flash photolysis. Here we use redox equilibration experiments to determine accurate relative oxidation potentials for the same amines. We also describe an extension of these experiments to show how relative oxidation potentials can be obtained in the absence of equilibrium, from a complete kinetic analysis of the reversible redox kinetics. The results provide support for the previous cyclic voltammetry/laser flash photolysis method for determining oxidation potentials.

  7. Analysis of Wind Data, Calculation of Energy Yield Potential, and Micrositing Application with WAsP

    Directory of Open Access Journals (Sweden)

    Fatih Topaloğlu

    2018-01-01

    Full Text Available The parameters required for building a wind power plant have been calculated using the fuzzy logic method by means of Wind Atlas Analysis and Application Program (WAsP in this study. Overall objectives of the program include analysis of raw data, evaluation of wind and climate, construction of a wind atlas, and estimation of wind power potential. With the analysis performed in the application, the average wind velocity, average power density, energy potential from micrositing, capacity factor, unit cost price, and period of redemption have been calculated, which are needed by the project developer during the decision-making stage and intended to be used as the input unit in the fuzzy logic-based system designed. It is aimed at processing the parameters calculated by the designed fuzzy logic-based decision-making system at the rule base and generating a compatibility factor that will allow for making the final decision in building wind power plants.

  8. Bioenergy potential of Ulva lactuca: Biomass yield, methane production and combustion

    DEFF Research Database (Denmark)

    Bruhn, Annette; Dahl, Jonas; Bangsø Nielsen, Henrik

    2011-01-01

    The biomass production potential at temperate latitudes (56°N), and the quality of the biomass for energy production (anaerobic digestion to methane and direct combustion) were investigated for the green macroalgae, Ulva lactuca. The algae were cultivated in a land based facility demonstrating...... in weight specific methane production compared to wet biomass. Ash and alkali contents are the main challenges in the use of U. lactuca for direct combustion. Application of a bio-refinery concept could increase the economical value of the U. lactuca biomass as well as improve its suitability for production...

  9. Expansion of Adult Human Pancreatic Tissue Yields Organoids Harboring Progenitor Cells with Endocrine Differentiation Potential

    Directory of Open Access Journals (Sweden)

    Cindy J.M. Loomans

    2018-03-01

    Full Text Available Summary: Generating an unlimited source of human insulin-producing cells is a prerequisite to advance β cell replacement therapy for diabetes. Here, we describe a 3D culture system that supports the expansion of adult human pancreatic tissue and the generation of a cell subpopulation with progenitor characteristics. These cells display high aldehyde dehydrogenase activity (ALDHhi, express pancreatic progenitors markers (PDX1, PTF1A, CPA1, and MYC, and can form new organoids in contrast to ALDHlo cells. Interestingly, gene expression profiling revealed that ALDHhi cells are closer to human fetal pancreatic tissue compared with adult pancreatic tissue. Endocrine lineage markers were detected upon in vitro differentiation. Engrafted organoids differentiated toward insulin-positive (INS+ cells, and circulating human C-peptide was detected upon glucose challenge 1 month after transplantation. Engrafted ALDHhi cells formed INS+ cells. We conclude that adult human pancreatic tissue has potential for expansion into 3D structures harboring progenitor cells with endocrine differentiation potential. : In the context of β cell replacement therapy for diabetes, de Koning and colleagues describe a 3D culture platform that supports ex vivo expansion of human pancreatic tissue as organoids. These organoids harbor a subpopulation of ALDHhi cells that display proliferative capacity and can differentiate to an endocrine fate. Keywords: pancreas, organoid, human, ALDH, endocrine differentiation, beta cells, insulin, progenitor, fetal, diabetes

  10. Corn Yield and Soil Nitrous Oxide Emission under Different Fertilizer and Soil Management: A Three-Year Field Experiment in Middle Tennessee.

    Science.gov (United States)

    Deng, Qi; Hui, Dafeng; Wang, Junming; Iwuozo, Stephen; Yu, Chih-Li; Jima, Tigist; Smart, David; Reddy, Chandra; Dennis, Sam

    2015-01-01

    A three-year field experiment was conducted to examine the responses of corn yield and soil nitrous oxide (N2O) emission to various management practices in middle Tennessee. The management practices include no-tillage + regular applications of urea ammonium nitrate (NT-URAN); no-tillage + regular applications of URAN + denitrification inhibitor (NT-inhibitor); no-tillage + regular applications of URAN + biochar (NT-biochar); no-tillage + 20% applications of URAN + chicken litter (NT-litter), no-tillage + split applications of URAN (NT-split); and conventional tillage + regular applications of URAN as a control (CT-URAN). Fertilizer equivalent to 217 kg N ha(-1) was applied to each of the experimental plots. Results showed that no-tillage (NT-URAN) significantly increased corn yield by 28% over the conventional tillage (CT-URAN) due to soil water conservation. The management practices significantly altered soil N2O emission, with the highest in the CT-URAN (0.48 mg N2O m(-2) h(-1)) and the lowest in the NT-inhibitor (0.20 mg N2O m(-2) h(-1)) and NT-biochar (0.16 mg N2O m(-2) h(-1)) treatments. Significant exponential relationships between soil N2O emission and water filled pore space were revealed in all treatments. However, variations in soil N2O emission among the treatments were positively correlated with the moisture sensitivity of soil N2O emission that likely reflects an interactive effect between soil properties and WFPS. Our results indicated that improved fertilizer and soil management have the potential to maintain highly productive corn yield while reducing greenhouse gas emissions.

  11. Energy Balance for a Sonoluminescence Bubble Yields a Measure of Ionization Potential Lowering

    Science.gov (United States)

    Kappus, B.; Bataller, A.; Putterman, S. J.

    2013-12-01

    Application of energy conservation between input sound and the microplasma which forms at the moment of sonoluminescence places bounds on the process, whereby the gas is ionized. Detailed pulsed Mie scattering measurements of the radius versus time for a xenon bubble in sulfuric acid provide a complete characterization of the hydrodynamics and minimum radius. For a range of emission intensities, the blackbody spectrum emitted during collapse matches the minimum bubble radius, implying opaque conditions are attained. This requires a degree of ionization >36%. Analysis reveals only 2.1±0.6eV/atom of energy available during light emission. In order to unbind enough charge, collective processes must therefore reduce the ionization potential by at least 75%. We interpret this as evidence that a phase transition to a highly ionized plasma is occurring during sonoluminescence.

  12. Genomics approaches to unlock the high yield potential of cassava, a tropical model plant

    Directory of Open Access Journals (Sweden)

    Shengkui ZHANG,Ping'an MA,Haiyan WANG,Cheng LU,Xin CHEN,Zhiqiang XIA,Meiling ZOU,Xinchen ZHOU,Wenquan WANG

    2014-12-01

    Full Text Available Cassava, a tropical food, feed and biofuel crop, has great capacity for biomass accumulation and an extraordinary efficiency in water use and mineral nutrition, which makes it highly suitable as a model plant for tropical crops. However, the understanding of the metabolism and genomics of this important crop is limited. The recent breakthroughs in the genomics of cassava, including whole-genome sequencing and transcriptome analysis, as well as advances in the biology of photosynthesis, starch biosynthesis, adaptation to drought and high temperature, and resistance to virus and bacterial diseases, are reviewed here. Many of the new developments have come from comparative analyses between a wild ancestor and existing cultivars. Finally, the current challenges and future potential of cassava as a model plant are discussed.

  13. Local conditions for the Pauli potential in order to yield self-consistent electron densities exhibiting proper atomic shell structure

    Energy Technology Data Exchange (ETDEWEB)

    Finzel, Kati, E-mail: kati.finzel@liu.se [Linköpings University, IFM Department of Physics, 58183 Linköping (Sweden)

    2016-01-21

    The local conditions for the Pauli potential that are necessary in order to yield self-consistent electron densities from orbital-free calculations are investigated for approximations that are expressed with the help of a local position variable. It is shown that those local conditions also apply when the Pauli potential is given in terms of the electron density. An explicit formula for the Ne atom is given, preserving the local conditions during the iterative procedure. The resulting orbital-free electron density exhibits proper shell structure behavior and is in close agreement with the Kohn-Sham electron density. This study demonstrates that it is possible to obtain self-consistent orbital-free electron densities with proper atomic shell structure from simple one-point approximations for the Pauli potential at local density level.

  14. Maximizing Amazonia's Ecosystem Services: Juggling the potential for carbon storage, agricultural yield and biodiversity in the Amazon

    Science.gov (United States)

    O'Connell, C. S.; Foley, J. A.; Gerber, J. S.; Polasky, S.

    2011-12-01

    The Amazon is not only an exceptionally biodiverse and carbon-rich tract of tropical forest, it is also a case study in land use change. Over the next forty years it will continue to experience pressure from an urbanizing and increasingly affluent populace: under a business-as-usual scenario, global cropland, pasture and biofuels systems will carry on expanding, while the Amazon's carbon storage potential will likely become another viable revenue source under REDD+. Balancing those competing land use pressures ought also take into account Amazonia's high - but heterogeneous - biodiversity. Knowing where Amazonia has opportunities to make efficient or optimal trade offs between carbon storage, agricultural production and biodiversity can allow policymakers to direct or influence LUC drivers. This analysis uses a spatially-explicit model that takes climate and management into account to quantify the potential agricultural yield of both the Amazon's most important agricultural commodities - sugar, soy and maize - as well as several that are going to come into increasing prominence, including palm oil. In addition, it maps the potential for carbon to be stored in forest biomass and relative species richness across Amazonia. We then compare carbon storage, agricultural yield and species richness and identify areas where efficient trade offs occur between food, carbon, and biodiversity - three critical ecosystem goods and services provided by the world's largest tropical forest.

  15. The dependence of maize (Zea mays hybrids yielding potential on the water amounts reaching the soil surface

    Directory of Open Access Journals (Sweden)

    Kresović Branka

    2013-01-01

    Full Text Available The aim of the present study was to observe the response of maize hybrids under rainfed and irrigation conditions of the soil in order to establish the dependence of yielding potential on the water amounts reaching the soil surface during the growing season. The four-replicate trail was set up according to the randomised complete-block design on chernozem. Pre-watering soil moisture was approximately 70% of field water capacity, and soil moisture was established thermogravimetrically. During the five-year studies, the following differences in yields could be as follows: 12.68 t ha-1 (ZP 341; 12.76 t ha-1 (ZP 434; 13.17 t ha-1 (ZP 578; 14.03 t ha-1 (ZP 684 and 13.75 t ha-1 (ZP 704 under conditions of 440 mm, 440 mm, 424 mm, 457 mm and 466 mm of water, respectively. The hybrid ZP 341, i.e. ZP 578 expressed the highest, i.e. the lowest tolerance in dry relative seasons, respectively. The reduction of the water amount for every 10 mm decreased the yield by 119.4 kg ha-1 (ZP 341, 156.7 kg ha-1 (ZP 434, 172.3 kg ha-1 (ZP 578, 148.9 kg ha-1 (ZP 684 and 151.1 kg ha-1 (ZP 704. [Projekat Ministarstva nauke Republike Srbije, br. TR 31037

  16. Soil salinity and matric potential interaction on water use, water use efficiency and yield response factor of bean and wheat.

    Science.gov (United States)

    Khataar, Mahnaz; Mohhamadi, Mohammad Hossien; Shabani, Farzin

    2018-02-08

    We studied the effects of soil matric potential and salinity on the water use (WU), water use efficiency (WUE) and yield response factor (Ky), for wheat (Triticum aestivum cv. Mahdavi) and bean (Phaseoulus vulgaris cv. COS16) in sandy loam and clay loam soils under greenhouse conditions. Results showed that aeration porosity is the predominant factor controlling WU, WUE, Ky and shoot biomass (Bs) at high soil water potentials. As matric potential was decreased, soil aeration improved, with Bs, WU and Ky reaching maximum value at -6 to -10 kPa, under all salinities. Wheat WUE remained almost unchanged by reduction of matric potential under low salinities (EC ≤ 8 dSm -1 ), but increased under higher salinities (EC ≥ 8 dSm -1 ), as did bean WUE at all salinities, as matric potential decreased to -33 kPa. Wheat WUE exceeds that of bean in both sandy loam and clay loam soils. WUE of both plants increased with higher shoot/root ratio and a high correlation coefficient exists between them. Results showed that salinity decreases all parameters, particularly at high potentials (h = -2 kPa), and amplifies the effects of waterlogging. Further, we observed a strong relationship between transpiration (T) and root respiration (Rr) for all experiments.

  17. Effects of ecological and conventional agricultural intensification practices on maize yields in sub-Saharan Africa under potential climate change

    International Nuclear Information System (INIS)

    Folberth, Christian; Yang, Hong; Gaiser, Thomas; Liu, Junguo; Wang, Xiuying; Williams, Jimmy; Schulin, Rainer

    2014-01-01

    Much of Africa is among the world’s regions with lowest yields in staple food crops, and climate change is expected to make it more difficult to catch up in crop production in particular in the long run. Various agronomic measures have been proposed for lifting agricultural production in Africa and to adapt it to climate change. Here, we present a projection of potential climate change impacts on maize yields under different intensification options in Sub-Saharan Africa (SSA) using an agronomic model, GIS-based EPIC (GEPIC). Fallow and nutrient management options taken into account are (a) conventional intensification with high mineral N supply and a bare fallow, (b) moderate mineral N supply and cowpea rotation, and (c) moderate mineral N supply and rotation with a fast growing N fixing tree Sesbania sesban. The simulations suggest that until the 2040s rotation with Sesbania will lead to an increase in yields due to increasing N supply besides improving water infiltration and soils’ water holding capacity. Intensive cultivation with a bare fallow or an herbaceous crop like cowpea in the rotation is predicted to result in lower yields and increased soil erosion during the same time span. However, yields are projected to decrease in all management scenarios towards the end of the century, should temperature increase beyond critical thresholds. The results suggest that the effect of eco-intensification as a sole means of adapting agriculture to climate change is limited in Sub-Saharan Africa. Highly adverse temperatures would rather have to be faced by improved heat tolerant cultivars, while strongly adverse decreases in precipitation would have to be faced by expanding irrigation where feasible. While the evaluation of changes in agro-environmental variables like soil organic carbon, erosion, and soil humidity hints that these are major factors influencing climate change resilience of the field crop, no direct relationship between these factors, crop yields

  18. Oxygen potential of uranium--plutonium oxide as determined by controlled-atmosphere thermogravimetry

    International Nuclear Information System (INIS)

    Swanson, G.C.

    1975-10-01

    The oxygen-to-metal atom ratio, or O/M, of solid solution uranium-plutonium oxide reactor fuel is a measure of the concentration of crystal defects in the oxide which affect many fuel properties, particularly, fuel oxygen potential. Fabrication of a high-temperature oxygen electrode, employing an electro-active tip of oxygen-deficient solid-state electrolyte, intended to confirm gaseous oxygen potentials is described. Uranium oxide and plutonium oxide O/M reference materials were prepared by in situ oxidation of high purity metals in the thermobalance. A solid solution uranium-plutonium oxide O/M reference material was prepared by alloying the uranium and plutonium metals in a yttrium oxide crucible at 1200 0 C and oxidizing with moist He at 250 0 C. The individual and solid solution oxides were isothermally equilibrated with controlled oxygen potentials between 800 and 1300 0 C and the equilibrated O/M ratios calculated with corrections for impurities and buoyancy effects. Use of a reference oxygen potential of -100 kcal/mol to produce an O/M of 2.000 is confirmed by these results. However, because of the lengthy equilibration times required for all oxides, use of the O/M reference materials rather than a reference oxygen potential is recommended for O/M analysis methods calibrations. (auth)

  19. Oxidative Stress and Antioxidant Potential of One Hundred Medicinal Plants.

    Science.gov (United States)

    Hassan, Waseem; Noreen, Hamsa; Rehman, Shakila; Gul, Shehnaz; Kamal, Mohammad Amjad; Kamdem, Jean Paul; Zaman, Bakht; da Rocha, Joao B T

    2017-01-01

    Reactive species are produced in biological system because of redox reactions. The imbalance in pro-oxidant and antioxidant homeostasis leads to the production of toxic reactive oxygen and nitrogen species like hydrogen peroxide, organic peroxides, hydroxyl radicals, superoxide anion and nitric oxide. Inactivation of metabolic enzymes, oxidation of biomolecules and cellular damage are some of the prominent characteristics of reactive species. Similarly, oxidative stress has been associated with more than one hundred (100) pathologies such as atherosclerosis, diabetes, cardiovascular diseases, pancreatic and liver diseases, joint disorders, cardiac fibrosis, acute respiratory distress syndrome, neurological diseases (amyotrophic lateral sclerosis, Huntington's disorder, Parkinson's disease and Alzheimer's disease), ageing and cancer etc. The toxicity of reactive species is balanced by the integrated antioxidant systems, which include enzymatic and non-enzymatic antioxidants. Antioxidant therapies or defenses protect the biological sites by removing or quenching the free radicals (prooxidants). Medicinal plants can not only protect the oxidative damage, but also play a vital role in health maintenance and prevention of chronic degenerative diseases. This review will provide a valuable discussion of one hundred (100) well known medicinal plants, which may add to the optimization of antioxidants rank. Besides, some of the antioxidant evaluation techniques or mechanisms via which medicinal plants act as antioxidants are also described. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  20. Characterization of the thrombogenic potential of surface oxides on stainless steel for implant purposes

    International Nuclear Information System (INIS)

    Shih, C.-C.; Shih, C.-M.; Su, Y.-Y.; Chang, M.-S.; Lin, S.-J.

    2003-01-01

    Marketed stents are manufactured from various metals and passivated with different degrees of surface oxidation. The functional surface oxides on the degree of antithrombotic potential were explored through a canine femoral extracorporeal circuit model. Related properties of these oxide films were studied by open-circuit potential, current density detected at open-circuit potential, the electrochemical impedance spectroscopy, transmission electron microscopy, Auger spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. Experimental evidences showed that blood clot weight after a 30-min follow-up was significantly lower for the stainless steel wire passivated with amorphous oxide (AO) compared to the wire passivated with polycrystalline oxide (PO) or commercial as-received wire coils (AS). Surface characterizations showed that a stable negative current density at open-circuit potential and a significant lower potential were found for the wire surface passivated with AO than for the surface passivated with PO. Time constant of AO is about 25 times larger than that of polycrystalline oxide. Significant difference in oxide grain sizes was found between PO and AO. Surface chemistries revealed by the AES and XPS spectra indicated the presence of a Cr- and oxygen-rich surface oxide for AO, and a Fe-rich and oxygen-lean surface oxide for PO. These remarkable characteristics of AO surface film might have a potential to provide for excellent antithrombotic characteristics for the 316L stainless steel stents

  1. Monoterpenol Oxidative Metabolism: Role in Plant Adaptation and Potential Applications

    Science.gov (United States)

    Ilc, Tina; Parage, Claire; Boachon, Benoît; Navrot, Nicolas; Werck-Reichhart, Danièle

    2016-01-01

    Plants use monoterpenols as precursors for the production of functionally and structurally diverse molecules, which are key players in interactions with other organisms such as pollinators, flower visitors, herbivores, fungal, or microbial pathogens. For humans, many of these monoterpenol derivatives are economically important because of their pharmaceutical, nutraceutical, flavor, or fragrance applications. The biosynthesis of these derivatives is to a large extent catalyzed by enzymes from the cytochrome P450 superfamily. Here we review the knowledge on monoterpenol oxidative metabolism in plants with special focus on recent elucidations of oxidation steps leading to diverse linalool and geraniol derivatives. We evaluate the common features between oxidation pathways of these two monoterpenols, such as involvement of the CYP76 family, and highlight the differences. Finally, we discuss the missing steps and other open questions in the biosynthesis of oxygenated monoterpenol derivatives. PMID:27200002

  2. Potential electrode materials for symmetrical Solid Oxide Fuel Cells

    Directory of Open Access Journals (Sweden)

    Ruiz Morales, J. C.

    2008-08-01

    Full Text Available Chromites, titanates and Pt-YSZ-CeO2 cermets have been investigated as potential electrode materials for an alternative concept of Solid Oxide Fuel Cell (SOFC, the symmetrical SOFCs (SFC. In this configuration, the same electrode material is used simultaneously as anode and cathode. Interconnector materials, such as chromites, could be considered as potential SFC electrodes, at least under pure hydrogen-fed at relatively high temperatures, as they do not exhibit significant catalytic activity towards hydrocarbon oxidation. This may be overcome by partially substituting Cr in the perovskite B-sites by other transition metal cations such as Mn. La0.75Sr0.25Cr0.5Mn0.5O3-δ (LSCM is a good candidate for such SFCs, rendering fuel cell performances in excess of 500 and 300mW/cm2 using pure H2 and CH4 as fuel, at 950 oC. Similarly, typical n-type electronic conductors traditionally regarded as anode materials, such as strontium titanates, may also operate under oxidising conditions as cathodes by substituting some Ti content for Fe to introduce p-type conductivity. Preliminary electrochemical experiments on La4Sr8Ti12-xFexO38-δ-based SFCs show that they perform reasonably well under humidified H2, at high temperatures. A third group of materials is the support material of any typical cermet anode, i.e. YSZ, CeO2 plus a current collector. It has been found that this combination could be optimised to operate as SFC electrodes, rendering performances of 400mW/cm2 under humidified pure H2 at 950oC.

    Cromitas, titanatos y cermets de Pt-YSZ-CeO2 han sido investigados como potenciales materiales de electrodo para un concepto alternativo de Pilas de Combustible de Óxidos Sólidos (SOFC, las pilas SOFC simétricas (SFC. En

  3. Nitric oxide radical scavenging potential of some Elburz medicinal ...

    African Journals Online (AJOL)

    Some plants scavenge nitric oxide (NO) with high affinity. For this purpose, forty extracts from 26 medicinal plants, growing extensively in Elburz mountains, were evaluated for their NO scavenging activity. Total phenolic and flavonoid contents of these extracts were also measured by Folin Ciocalteu and AlCl3 colorimetric ...

  4. In vitro potential cytogenetic and oxidative stress effects of roxithromycin.

    Science.gov (United States)

    Arslan, Mehmet; Timocin, Taygun; Ila, Hasan B

    2017-10-01

    Macrolide antibiotic roxithromycin was evaluated in terms of its genotoxic, cytotoxic and oxidative stress effects. For this purpose; 25, 50, 100 and 200 μg/mL concentrations of roxithromycin were dissolved in dimethyl sulfoxide and treated to human peripheral blood lymphocytes for two different treatment periods (24 and 48 h). In chromosome aberration (CA) and micronucleus (MN) tests, roxithromycin did not show genotoxic effect. But it induced sister chromatid exchange (SCE) at the highest concentration (200 μg/mL) for the 24-h treatment period and at all concentrations (except 25 μg/mL) for the 48-h treatment period. Looking at cytotoxic effect of roxithromycin, statistically insignificant decreases on mitotic index and proliferation index were observed. Roxithromycin decreased nuclear division index (NDI) at highest two concentrations (100 and 200 μg/mL) for the 24-h treatment period and at all concentrations (expect 25 μg/mL) for the 48-h treatment period. Total oxidant values, total antioxidant values and oxidative stress index did not change with roxithromycin treatment. Eventually, roxithromycin did not have genotoxic and oxidative stress effects in human-cultured lymphocytes.

  5. Assessment of Potential Climate Change Effects on the Rice Yield and Water Footprint in the Nanliujiang Catchment, China

    Directory of Open Access Journals (Sweden)

    Mingzhi Yang

    2018-01-01

    Full Text Available The Nanliujiang catchment is one of major rice production bases of South China. Irrigation districts play an important role in rice production which requires a large quantity of water. There are potential risks on future climate change in response to rice production, agricultural irrigation water use and pollution control locally. The SWAT model was used to quantify the yield and water footprint (WF of rice in this catchment. A combined method of automatic and manual sub-basin delineation was used for the model setup in this work to reflect the differences between irrigation districts in yield and water use of rice. We validated our simulations against observed leaf area index, biomass and yield of rice, evapotranspiration and runoff. The outputs of three GCMs (GFDL-ESM2M, IPSL-CM5A-LR and HadGEM2-ES under three RCPs (RCP2.6, 4.5, 8.5 were fed to the SWAT model. The results showed that: (a the SWAT model is an ideal tool to simulate rice development as well as hydrology; (b there would be increases in rice yield ranged from +1.4 to +10.6% under climate projections of GFDL-ESM2M and IPSL-CM5A-LR but slight decreases ranged from −3.5 to −0.8% under that of HadGEM2-ES; (c the yield and WFs of rice displayed clear differences in the catchment, with a characteristic that high in the south and low in the north, mainly due to the differences in climatic conditions, soil quality and fertilization amount; (d there would be a decrease by 45.5% in blue WF with an increase by 88.1% in green WF, which could provide favorable conditions to enlarge irrigated areas and take technical measures for improving green water use efficiency of irrigation districts; (e a clear rise in future grey WF would present enormous challenges for the protection of water resources and environmental pollution control in this catchment. So it should be to improved nutrient management strategies for the agricultural non-point source pollution control in irrigation districts

  6. Establishment, Growth, and Yield Potential of the Perennial Grass Miscanthus × Giganteus on Degraded Coal Mine Soils

    Directory of Open Access Journals (Sweden)

    Stanisław Jeżowski

    2017-06-01

    Full Text Available Miscanthus × giganteus is a giant C4 grass native to Asia. Unlike most C4 species, it is relatively cold tolerant due to adaptations across a wide range of altitudes. These grasses are characterized by high productivity and low input requirements, making them excellent candidates for bioenergy feedstock production. The aim of this study was to investigate the potential for growing Miscanthus on extremely marginal soils, degraded by open lignite (brown coal mining. Field experiments were established within three blocks situated on waste heaps originating from the lignite mine. Analyses were conducted over the first 3 years following Miscanthus cultivation, focusing on the effect of organic and mineral fertilization on crop growth, development and yield in this extreme environment. The following levels of fertilization were implemented between the blocks: the control plot with no fertilization (D0, a plot with sewage sludge (D1, a plot with an identical amount of sewage sludge plus one dose of mineral fertilizer (D2 and a plot with an identical amount of sewage sludge plus a double dose of mineral fertilizer (D3. Crop development and characteristics (plant height, tillering, and biomass yield [dry matter] were measured throughout the study period and analyzed using Analysis of Variance (ANOVA. Significant differences were apparent between plant development and 3rd year biomass production over the course of the study (0.964 kg plant-1 for DO compared to 1.503 kg plant-1 for D1. Soil analyses conducted over the course of the experiment showed that organic carbon levels within the soil increased significantly following the cultivation of Miscanthus, and overall, pH decreased. With the exception of iron, macronutrient concentrations remained stable throughout. The promising yields and positive effects of Miscanthus on the degraded soil suggests that long term plantations on land otherwise unsuitable for agriculture may prove to be of great

  7. Reduction of oxidative cellular damage by overexpression of the thioredoxin TRX2 gene improves yield and quality of wine yeast dry active biomass

    Directory of Open Access Journals (Sweden)

    Ros Joaquim

    2010-02-01

    Full Text Available Abstract Background Wine Saccharomyces cerevisiae strains, adapted to anaerobic must fermentations, suffer oxidative stress when they are grown under aerobic conditions for biomass propagation in the industrial process of active dry yeast production. Oxidative metabolism of sugars favors high biomass yields but also causes increased oxidation damage of cell components. The overexpression of the TRX2 gene, coding for a thioredoxin, enhances oxidative stress resistance in a wine yeast strain model. The thioredoxin and also the glutathione/glutaredoxin system constitute the most important defense against oxidation. Trx2p is also involved in the regulation of Yap1p-driven transcriptional response against some reactive oxygen species. Results Laboratory scale simulations of the industrial active dry biomass production process demonstrate that TRX2 overexpression increases the wine yeast final biomass yield and also its fermentative capacity both after the batch and fed-batch phases. Microvinifications carried out with the modified strain show a fast start phenotype derived from its enhanced fermentative capacity and also increased content of beneficial aroma compounds. The modified strain displays an increased transcriptional response of Yap1p regulated genes and other oxidative stress related genes. Activities of antioxidant enzymes like Sod1p, Sod2p and catalase are also enhanced. Consequently, diminished oxidation of lipids and proteins is observed in the modified strain, which can explain the improved performance of the thioredoxin overexpressing strain. Conclusions We report several beneficial effects of overexpressing the thioredoxin gene TRX2 in a wine yeast strain. We show that this strain presents an enhanced redox defense. Increased yield of biomass production process in TRX2 overexpressing strain can be of special interest for several industrial applications.

  8. Polyol synthesis, functionalisation, and biocompatibility studies of superparamagnetic iron oxide nanoparticles as potential MRI contrast agents

    Science.gov (United States)

    Hachani, Roxanne; Lowdell, Mark; Birchall, Martin; Hervault, Aziliz; Mertz, Damien; Begin-Colin, Sylvie; Thanh, Nguy&Ecirtil; N. Thi&Cmb. B. Dot; Kim

    2016-02-01

    Iron oxide nanoparticles (IONPs) of low polydispersity were obtained through a simple polyol synthesis in high pressure and high temperature conditions. The control of the size and morphology of the nanoparticles was studied by varying the solvent used, the amount of iron precursor and the reaction time. Compared with conventional synthesis methods such as thermal decomposition or co-precipitation, this process yields nanoparticles with a narrow particle size distribution in a simple, reproducible and cost effective manner without the need for an inert atmosphere. For example, IONPs with a diameter of ca. 8 nm could be made in a reproducible manner and with good crystallinity as evidenced by X-ray diffraction analysis and high saturation magnetization value (84.5 emu g-1). The surface of the IONPs could be tailored post synthesis with two different ligands which provided functionality and stability in water and phosphate buffer saline (PBS). Their potential as a magnetic resonance imaging (MRI) contrast agent was confirmed as they exhibited high r1 and r2 relaxivities of 7.95 mM-1 s-1 and 185.58 mM-1 s-1 respectively at 1.4 T. Biocompatibility and viability of IONPs in primary human mesenchymal stem cells (hMSCs) was studied and confirmed.Iron oxide nanoparticles (IONPs) of low polydispersity were obtained through a simple polyol synthesis in high pressure and high temperature conditions. The control of the size and morphology of the nanoparticles was studied by varying the solvent used, the amount of iron precursor and the reaction time. Compared with conventional synthesis methods such as thermal decomposition or co-precipitation, this process yields nanoparticles with a narrow particle size distribution in a simple, reproducible and cost effective manner without the need for an inert atmosphere. For example, IONPs with a diameter of ca. 8 nm could be made in a reproducible manner and with good crystallinity as evidenced by X-ray diffraction analysis and high

  9. Role of nitric oxide in long-term potentiation of the rat medial vestibular nuclei.

    Science.gov (United States)

    Grassi, S; Pettorossi, V E

    2000-01-01

    In rat brainstem slices, we investigated the role of nitric oxide in long-term potentiation induced in the ventral portion of the medial vestibular nuclei by high-frequency stimulation of the primary vestibular afferents. The nitric oxide scavenger [2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide ] and the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester were administered before and after induction of potentiation. Both drugs completely prevented long-term potentiation, whereas they did not impede the potentiation build-up, or affect the already established potentiation. These results demonstrate that the induction, but not the maintenance of vestibular long-term potentiation, depends on the synthesis and release into the extracellular medium of nitric oxide. In addition, we analysed the effect of the nitric oxide donor sodium nitroprusside on vestibular responses. Sodium nitroprusside induced long-term potentiation, as evidenced through the field potential enhancement and unit peak latency decrease. This potentiation was impeded by D, L-2-amino-5-phosphonopentanoic acid, and was reduced under blockade of synaptosomal platelet-activating factor receptors by ginkgolide B and group I metabotropic glutamate receptors by (R,S)-1-aminoindan-1, 5-dicarboxylic acid. When reduced, potentiation fully developed following the washout of antagonist, demonstrating an involvement of platelet-activating factor and group I metabotropic glutamate receptors in its full development. Potentiation induced by sodium nitroprusside was also associated with a decrease in the paired-pulse facilitation ratio, which persisted under ginkgolide B, indicating that nitric oxide increases glutamate release independently of platelet-activating factor-mediated presynaptic events. We suggest that nitric oxide, released after the activation of N-methyl-D-aspartate receptors, acts as a retrograde messenger leading to an enhancement of glutamate release to a

  10. Potential of reversible solid oxide cells as electricity storage system

    OpenAIRE

    Di Giorgio, Paolo; Desideri, Umberto

    2016-01-01

    Electrical energy storage (EES) systems allow shifting the time of electric power generation from that of consumption, and they are expected to play a major role in future electric grids where the share of intermittent renewable energy systems (RES), and especially solar and wind power plants, is planned to increase. No commercially available technology complies with all the required specifications for an efficient and reliable EES system. Reversible solid oxide cells (ReSOC) working in both ...

  11. Phenotyping Drought Tolerance and Yield Potential of Warm-Season Legumes Through Field- and Airborne-Based Hyperspectral VSWIR Sensing

    Science.gov (United States)

    Drewry, D.; Berny-Mier y Teran, J. C.; Dutta, D.; Gepts, P.

    2017-12-01

    Hyperspectral sensing in the visible through shortwave infrared (VSWIR) portion of the spectrum has been demonstrated to provide significant information on the structural and functional properties of vegetation, resulting in powerful techniques to discern species differences, characterize crop nutrient or water stress, and quantify the density of foliage in agricultural fields. Modern machine-learning techniques allow for the entire set of spectral bands, on the order of hundreds with modern field and airborne spectrometers, to be used to develop models that can simultaneously retrieve a variety of foliar chemical compounds and hydrological and structural states. The application of these techniques, in the context of leaf-level measurements of VSWIR reflectance, or more complicated remote airborne surveys, has the potential to revolutionize high-throughput methods to phenotype germplasm that optimizes yield, resource-use efficiencies, or alternate objectives related to disease resistance or biomass accumulation, for example. Here we focus on breeding trials for a set of warm-season legumes, conducted in both greenhouse and field settings, and spanning a set of diverse genotypes providing a range of adaptation to drought and yield potential in the context of the semi-arid climate cultivation. At the leaf-level, a large set of spectral reflectance measurements spanning 400-2500 nanometers were made for plants across various growth stages in field experiments that induced severe drought, along with sampling for relevant trait values. Here we will discuss the development and performance of algorithms for a range of leaf traits related to gas exchange, leaf structure, hydrological status, nutrient contents and stable isotope discrimination, along with their relationships to drought resistance and yield. We likewise discuss the effectiveness of quantifying relevant foliar and canopy traits through airborne imaging spectroscopy from small unmanned vehicles (sUAVs), and

  12. Oxidative potential of secondary organic aerosols produced from photooxidation of different hydrocarbons using outdoor chamber under ambient sunlight

    Science.gov (United States)

    Jiang, Huanhuan; Jang, Myoseon; Sabo-Attwood, Tara; Robinson, Sarah E.

    2016-04-01

    The oxidative potential of various secondary organic aerosols (SOA) was measured using dithiothreitol (DTT) assay to understand how organic aerosols react with cellular materials. SOA was produced via the photooxidation of four different hydrocarbons (toluene, 1,3,5-trimethylbenzene, isoprene and α-pinene) in the presence of NOx using a large outdoor photochemical smog chamber. The DTT consumption rate was normalized by the aerosol mass, which is expressed as DTTmass. Toluene SOA and isoprene SOA yielded higher DTTmass than 1,3,5-trimethylbenzene SOA or α-pinene SOA. In order to discover the correlation between the molecular structure and oxidative potential, the DTT responses of selected model compounds were also measured. Among them, conjugated aldehydes, quinones, and H2O2 showed considerable DTT response. To investigate the correlation between DTT response and cell responses in vitro, the expression of biological markers, i.e. IL-6, IL-8, and HMOX-1 were studied using small airway epithelial cells. Higher cellular expression of IL-8 was observed with toluene SOA exposure compared to 1,3,5-trimethylbenzene SOA exposure, which aligned with the results from DTT assay. Our study also suggests that within the urban atmosphere, the contribution of toluene SOA and isoprene SOA to the oxidative potential of ambient SOA will be more significant than that of α-pinene SOA.

  13. Potential Hydrogen Yields from Ultramafic Rocks of the Coast Range Ophiolite and Zambales Ophiolite: Inferences from Mössbauer Spectroscopy

    Science.gov (United States)

    Stander, A.; Nelms, M.; Wilkinson, K.; Dyar, M. D.; Cardace, D.

    2013-12-01

    The reduced status of mantle rocks is a possible controller and indicator of deep life habitat, due to interactions between water and ultramafic (Fe, Mg-rich) minerals, which, under reducing conditions, can yield copious free hydrogen, which is an energy source for rock-hosted chemosynthetic life. In this work, Mössbauer spectroscopy was used to parameterize the redox status of Fe in altering peridotites of the Coast Range Ophiolite (CRO) in California, USA and Zambales Ophiolite (ZO) in the Philippines. Fe-bearing minerals were identified and data were collected for the percentages of Fe(III)and Fe(II)and bulk Fe concentration. Thin section analysis shows that relict primary olivines and spinels generally constitute a small percentage of the ZO and CRO rock, and given satisfactory estimates of the volume of the ultramafic units of the ZO and CRO, a stoichiometric H2 production can be estimated. In addition, ZO serpentinites are ~63,000 ppm Fe in bulk samples; they contain ~41-58% Fe(III)and ~23-34% Fe(II) in serpentine and relict minerals along with ~8-30% of the total Fe as magnetite. CRO serpentinites are ~42,000 ppm Fe in bulk samples; they contain ~15-50% Fe(III), ~22-88% Fe(II) in serpentine and relict minerals, and ~0-52% of total Fe is in magnetite (Fe(II)Fe(III)2O4). Assuming stoichiometric production of H2, and given the following representation of serpentinization 2(FeO)rock + H2O → (Fe2O3)rock +H2, we calculated the maximum quantity of hydrogen released and yet to be released through the oxidation of Fe(II). Given that relatively high Fe(III)/Fetotal values can imply higher water:rock ratios during rock alteration (Andreani et al., 2013), we can deduce that ZO ultramafics in this study have experienced a net higher water:rock ratio than CRO ultramafics. We compare possible H2 yields and contrast the tectonic and alteration histories of the selected ultramafic units. (M. Andreani, M. Muñoz, C. Marcaillou, A. Delacour, 2013, μXANES study of iron

  14. The potential of methane-oxidizing bacteria for applications in environmental biotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Wendlandt, Karin-Dagmar; Stottmeister, Ulrich; Jechorek, Mirko [Helmholtz-Center for Environmental Research UFZ, Leipzig (Germany); Helm, Jana [School of Physics and Astronomy, The University of Edinburgh, Edinburgh (United Kingdom); Soltmann, Bettina [Institute for Materials Science, Dresden University of Technology, Dresden (Germany); Beck, Matthias [Oncotec, Pharma Production GmbH, Dessau-Rosslau (Germany)

    2010-04-15

    Methanotrophic bacteria possess a unique set of enzymes enabling them to oxidize, degrade and transform organic molecules and synthesize new compounds. Therefore, they have great potential in environmental biotechnology. The application of these unique properties was demonstrated in three case studies: (i) Methane escaping from leaky gas pipes may lead to massive mortality of trees in urban areas. Lack of oxygen within the soil surrounding tree roots caused by methanotrophic activity was identified as one of the reasons for this phenomenon. The similarity between metabolic reactions performed by the key enzymes of methanotrophs (methane monooxygenase) and ammonium oxidizers (ammonium monooxygenase) might offer a solution to this problem by applying commercially available nitrification and urease inhibitors. (ii) Methanotrophs are able to co-metabolically degrade contaminants such as low-molecular-weight-chlorinated hydrocarbons in soil and water in the presence of methane. Batch and continuous trichloroethylene degradation experiments in laboratory-scale reactors using Methylocystis sp. GB 14 were performed, partly with cells entrapped in a polymer matrix. (iii) Using a short, two-stage pilot-scale process, the intracellular polymer accumulation of poly-{beta}-hydroxybutyrate (PHB) in methanotrophs reached a maximum of 52%. Interestingly, an ultra-high-molecular-weight PHB of 3.1 MDa was accumulated under potassium deficiency. Under strictly controlled conditions (temperature, pH and methane supply) this process can be nonsterile because of the establishment of a stable microbial community (dominant species Methylocystis sp. GB 25 {>=}86% by biomass). The possibility to substitute methane with biogas from renewable sources facilitates the development of a methane-based PHB production process that yields a high-quality biopolymer at competitive costs. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  15. Long-term no-tillage application increases soil organic carbon, nitrous oxide emissions and faba bean (Vicia faba L.) yields under rain-fed Mediterranean conditions.

    Science.gov (United States)

    Badagliacca, Giuseppe; Benítez, Emilio; Amato, Gaetano; Badalucco, Luigi; Giambalvo, Dario; Laudicina, Vito Armando; Ruisi, Paolo

    2018-05-20

    The introduction of legumes into crop sequences and the reduction of tillage intensity are both proposed as agronomic practices to mitigate the soil degradation and negative impact of agriculture on the environment. However, the joint effects of these practices on nitrous oxide (N 2 O) and ammonia (NH 3 ) emissions from soil remain unclear, particularly concerning semiarid Mediterranean areas. In the frame of a long-term field experiment (23 years), a 2-year study was performed on the faba bean (Vicia faba L.) to evaluate the effects of the long-term use of no tillage (NT) compared to conventional tillage (CT) on yield and N 2 O and NH 3 emissions from a Vertisol in a semiarid Mediterranean environment. Changes induced by the tillage system in soil bulk density, water filled pore space (WFPS), organic carbon (TOC) and total nitrogen (TN), denitrifying enzyme activity (DEA), and bacterial gene (16S, amoA, and nosZ) abundance were measured as parameters potentially affecting N gas emissions. No tillage, compared with CT, significantly increased the faba bean grain yield by 23%. The tillage system had no significant effect on soil NH 3 emissions. Total N 2 O emissions, averaged over two cropping seasons, were higher in NT than those in CT plots (2.58 vs 1.71 kg N 2 O-N ha -1 , respectively; P emissions in NT plots were ascribed to the increase of soil bulk density and WFPS, bacteria (16S abundance was 96% higher in NT than that in CT) and N cycle genes (amoA and nosZ abundances were respectively 154% and 84% higher in NT than that in CT). The total N 2 O emissions in faba bean were similar to those measured in other N-fertilized crops. In conclusion, a full evaluation of NT technique, besides the benefits on soil characteristics (e.g. TOC increase) and crop yield, must take into account some criticisms related to the increase of N 2 O emissions compared to CT. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Anesthetic-Induced Oxidative Stress and Potential Protection

    Directory of Open Access Journals (Sweden)

    Cheng Wang

    2010-01-01

    Full Text Available Prolonged exposure of developing mammals to general anesthetics affects the N-methyl-D-aspartate (NMDA–type glutamate or γ-aminobutyric acid (GABA receptor systems and enhances neuronal toxicity. Stimulation of immature neurons by NMDA antagonists or GABA agonists is thought to increase overall nervous system excitability and may contribute to abnormal neuronal cell death during development. Although the precise mechanisms by which NMDA antagonists or GABA agonists cause neuronal cell death are still not completely understood, up-regulation of the NMDA receptor subunit NR1 may be an initiative factor in neuronal cell death. It is increasingly apparent that mitochondria lie at the center of the cell death regulation process. Evidence for the role of oxidative stress in anesthetic-induced neurotoxicity has been generated in studies that apply oxidative stress blockers. Prevention of neuronal death by catalase and superoxide dismutase in vitro, or by M40403 (superoxide dismutase mimetic in vivo, supports the contention that the involvement of reactive oxygen species (ROS and the nature of neuronal cell death in rodents is mainly apoptotic. However, more evidence is necessary to in order verify the role of the NMDA receptor subunit NR1 and ROS in anesthetic-induced neurodegeneration.

  17. Contrasts in oxidative potential and other particulate matter characteristics collected near major streets and background locations

    NARCIS (Netherlands)

    Boogaard, H.; Janssen, N.A.H.; Fischer, P.H.; Kos, G.P.A.; Weijers, E.P.; Cassee, F.R.; van der Zee, S.C.; Hartog, J. de; Brunekreef, B.; Hoek, G.

    2012-01-01

    BACKGROUND: Measuring the oxidative potential of airborne particulate matter (PM) may provide a more health-based exposure measure by integrating various biologically relevant properties of PM into a single predictor of biological activity. OBJECTIVES: We aimed to assess the contrast in oxidative

  18. Contrasts in oxidative potential and other particulate matter characteristics collected near major streets and background locations.

    NARCIS (Netherlands)

    Boogaard, H.; Janssen, N.A.; Fischer, P.H.; Kos, G.P.; Weijers, E.P.; Cassee, F.R.; Zee, S.C. van der; Hartog, J.J. de; Brunekreef, B.; Hoek, G.

    2012-01-01

    BACKGROUND: Measuring the oxidative potential of airborne particulate matter (PM) may provide a more health-based exposure measure by integrating various biologically relevant properties of PM into a single predictor of biological activity. OBJECTIVES: We aimed to assess the contrast in oxidative

  19. Tetrathiafulvalene S-oxide: a Potential Donor Impurity in the Organic Metal TTF-TCNQ

    DEFF Research Database (Denmark)

    Carlsen, Lars; Bechgaard, Klaus; Jacobsen, Claus Schelde

    1979-01-01

    Tetrathiafulvalene S-oxide, which because of its size similarity with tetrathiafulvalene is a potential ‘donor impurity’ in the organic metal TTF–TCNQ, was prepared and characterized spectroscopically. Experiments in which tetrathiafulvalene S-oxide was purposely doped into TTF–TCNQ indicate, how...

  20. Potentiating effect of ecofriendly synthesis of copper oxide ...

    Indian Academy of Sciences (India)

    diseases, however, it necessitates clinical studies to ascertain their potential as antimicrobial and anticancer agents. ... erties would result in interesting new applications of metal .... [13] South G R and Whittick A 1987 Introduction to psychology.

  1. Potential Impact of Climate Change on Suspended Sediment Yield in NW Spain: A Case Study on the Corbeira Catchment

    Directory of Open Access Journals (Sweden)

    M. Luz Rodríguez-Blanco

    2016-10-01

    Full Text Available Soil losses and the subsequent sediment delivery constitute significant environmental threats. Climate change is likely to have an impact on the availability of water and therefore on sediment yield in catchments. In this context, quantifying the sediment response to an increased atmospheric CO2 concentration and climate change is of utmost importance to the proper management of rural catchments. However, quantitative assessment of climate change impact remains a complex task. In this study, the potential medium (2031–2060 and long-term (2069–2098 impacts of projected changes of temperature, rainfall and CO2 concentration on sediment yield in a small rural catchment located in NW Spain were evaluated using the Soil and Water Assessment Tool (SWAT model. Climate change scenarios were created using future climate data projected by regional climate models from the ENSEMBLES project and two CO2 concentration scenarios (550 and 660 ppm. The results showed that climate change would have a noticeable impact on suspended sediment if the forecast temperature, rainfall and CO2 concentration changes included in this study were met. Overall, suspended sediment is expected to decrease (2031–2060: −11%, 2069–2098: −8% compared to the baseline period (1981–2010, mainly due to decreased streamflow. However, an increase in sediment transport in winter is predicted, possibly associated with increased erosion in cultivated areas (11%–17%, suggesting that, at this time of the year, the effect of soil detachment prevails over sediment transport capacity. Consequently, management practices aimed at reducing soil erosion in cultivated areas should be carried out, because these are the main source of sediment in the study area.

  2. Oxidation potential (E/sub h/) and pH control during experimentation

    International Nuclear Information System (INIS)

    Seitz, M.G.

    1982-01-01

    Purpose of this statement is to introduce the subject of oxidation potential, E/sub h/, and to discuss its control in experiments. After the concept of E/sub h/ is reviewed, the range of oxidation potentials expected to be associated with a repository for high level nuclear waste will be addressed. Finally, three laboratory methods of controlling E/sub h/ will be described, along with some perspective that has been derived from experience given for each method

  3. Heat waves imposed during early pod development in soybean (Glycine max) cause significant yield loss despite a rapid recovery from oxidative stress.

    Science.gov (United States)

    Siebers, Matthew H; Yendrek, Craig R; Drag, David; Locke, Anna M; Rios Acosta, Lorena; Leakey, Andrew D B; Ainsworth, Elizabeth A; Bernacchi, Carl J; Ort, Donald R

    2015-08-01

    Heat waves already have a large impact on crops and are predicted to become more intense and more frequent in the future. In this study, heat waves were imposed on soybean using infrared heating technology in a fully open-air field experiment. Five separate heat waves were applied to field-grown soybean (Glycine max) in central Illinois, three in 2010 and two in 2011. Thirty years of historical weather data from Illinois were analyzed to determine the length and intensity of a regionally realistic heat wave resulting in experimental heat wave treatments during which day and night canopy temperatures were elevated 6 °C above ambient for 3 days. Heat waves were applied during early or late reproductive stages to determine whether and when heat waves had an impact on carbon metabolism and seed yield. By the third day of each heat wave, net photosynthesis (A), specific leaf weight (SLW), and leaf total nonstructural carbohydrate concentration (TNC) were decreased, while leaf oxidative stress was increased. However, A, SLW, TNC, and measures of oxidative stress were no different than the control ca. 12 h after the heat waves ended, indicating rapid physiological recovery from the high-temperature stress. That end of season seed yield was reduced (~10%) only when heat waves were applied during early pod developmental stages indicates the yield loss had more to do with direct impacts of the heat waves on reproductive process than on photosynthesis. Soybean was unable to mitigate yield loss after heat waves given during late reproductive stages. This study shows that short high-temperature stress events that reduce photosynthesis and increase oxidative stress resulted in significant losses to soybean production in the Midwest, U.S. The study also suggests that to mitigate heat wave-induced yield loss, soybean needs improved reproductive and photosynthetic tolerance to high but increasingly common temperatures. Published 2015. This article is a U.S. Government work and is

  4. The Effect of Water Deficit stress on Osmotic Metabolites and Anti Oxidant System and Grain and Oil Yield of Amaranth CV. Koniz

    Directory of Open Access Journals (Sweden)

    Mehrdad Yarnia

    2015-01-01

    Full Text Available Drought is one of the most important environmental stresses that highly affect crop growth and yield. But the response of crops to stress depending on the timing of crop growth stages is different. The purpose of this study was to investigate effect of different levels of water stress (irrigation after 50, 80, 110, 140 and 170 mm evaporation from pan on different stages of Amaranth growth (establishment, branching, flowering and grain filling. To find the effects of water deficit stress on this plant it was decided to determine its protein percentage, oil and grain yields under drought stress. Evaluation of physiological characteristics as to the extent of osmotic adjustment and antioxidant activity was also carried out. Results showed that water deficit stress,depending on the severity and duration of stress, caused a reduction between between a minimum of 10 to a maximum of 89 percent in yield, 28 to 70 percent in harvest index, 12 to 32 percent in grain protein and 29 to 97 percent in oil yield. This indicates the high sensitivity of grain and oil yields to severe and prolonged drought stresses. Changes in osmotic substances (proline and soluble carbohydrates showed that this crop under water stress conditions increased proline and soluble carbohydrates by 31 and 50 percents, respectively. Thus, if could be said that under severe droughts the ability of crops to cops with drought will be reduced. Similarly, amaranth, to cope with water stress, increases the amount of antioxidant enzymes like catalase, peroxidase and super oxid dismutase up to 53, 23 and 79%, respectively. Higher amount of super oxid dismutase enzyme produce as the result of drought stress may play an important role to cope with reactive oxygen species and oxidative stresses.

  5. Modelling predicts that tolerance to drought during reproductive development will be required for high yield potential and stability of wheat in Europe

    Science.gov (United States)

    Semenov, Mikhail A.; Stratonovitch, Pierre; Paul, Matthew J.

    2017-04-01

    Short periods of extreme weather, such as a spell of high temperature or drought during a sensitive stage of development, could result in substantial yield losses due to reduction in grain number and grain size. In a modelling study (Stratonovitch & Semenov 2015), heat tolerance around flowering in wheat was identified as a key trait for increased yield potential in Europe under climate change. Ji et all (Ji et al. 2010) demonstrated cultivar specific responses of yield to drought stress around flowering in wheat. They hypothesised that carbohydrate supply to anthers may be the key in maintaining pollen fertility and grain number in wheat. It was shown in (Nuccio et al. 2015) that genetically modified varieties of maize that increase the concentration of sucrose in ear spikelets, performed better under non-drought and drought conditions in field experiments. The objective of this modelling study was to assess potential benefits of tolerance to drought during reproductive development for wheat yield potential and yield stability across Europe. We used the Sirius wheat model to optimise wheat ideotypes for 2050 (HadGEM2, RCP8.5) climate scenarios at selected European sites. Eight cultivar parameters were optimised to maximise mean yields, including parameters controlling phenology, canopy growth and water limitation. At those sites where water could be limited, ideotypes sensitive to drought produced substantially lower mean yields and higher yield variability compare with tolerant ideotypes. Therefore, tolerance to drought during reproductive development is likely to be required for wheat cultivars optimised for the future climate in Europe in order to achieve high yield potential and yield stability.

  6. Using satellite data to identify the causes of and potential solutions for yield gaps in India’s Wheat Belt

    Science.gov (United States)

    Jain, M.; Singh, Balwinder; Srivastava, A. A. K.; Malik, R. K.; McDonald, A. J.; Lobell, D. B.

    2017-09-01

    Food security will be increasingly challenged by climate change, natural resource degradation, and population growth. Wheat yields, in particular, have already stagnated in many regions and will be further affected by warming temperatures. Despite these challenges, wheat yields can be increased by improving management practices in regions with existing yield gaps. To identify the magnitude and causes of current yield gaps in India, one of the largest wheat producers globally, we produced 30 meter resolution yield maps from 2001 to 2015 across the Indo-Gangetic Plains (IGP), the nation’s main wheat belt. Yield maps were derived using a new method that translates satellite vegetation indices to yield estimates using crop model simulations, bypassing the need for ground calibration data. This is one of the first attempts to apply this method to a smallholder agriculture system, where ground calibration data are rarely available. We find that yields can be increased by 11% on average and up to 32% in the eastern IGP by improving management to current best practices within a given district. Additionally, if current best practices from the highest-yielding state of Punjab are implemented in the eastern IGP, yields could increase by almost 110%. Considering the factors that most influence yields, later sow dates and warmer temperatures are most associated with low yields across the IGP. This suggests that strategies to reduce the negative effects of heat stress, like earlier sowing and planting heat-tolerant wheat varieties, are critical to increasing wheat yields in this globally-important agricultural region.

  7. Potential of Reversible Solid Oxide Cells as Electricity Storage System

    Directory of Open Access Journals (Sweden)

    Paolo Di Giorgio

    2016-08-01

    Full Text Available Electrical energy storage (EES systems allow shifting the time of electric power generation from that of consumption, and they are expected to play a major role in future electric grids where the share of intermittent renewable energy systems (RES, and especially solar and wind power plants, is planned to increase. No commercially available technology complies with all the required specifications for an efficient and reliable EES system. Reversible solid oxide cells (ReSOC working in both fuel cell and electrolysis modes could be a cost effective and highly efficient EES, but are not yet ready for the market. In fact, using the system in fuel cell mode produces high temperature heat that can be recovered during electrolysis, when a heat source is necessary. Before ReSOCs can be used as EES systems, many problems have to be solved. This paper presents a new ReSOC concept, where the thermal energy produced during fuel cell mode is stored as sensible or latent heat, respectively, in a high density and high specific heat material and in a phase change material (PCM and used during electrolysis operation. The study of two different storage concepts is performed using a lumped parameters ReSOC stack model coupled with a suitable balance of plant. The optimal roundtrip efficiency calculated for both of the configurations studied is not far from 70% and results from a trade-off between the stack roundtrip efficiency and the energy consumed by the auxiliary power systems.

  8. Effects of Muscle-Specific Oxidative Stress on Cytochrome c Release and Oxidation-Reduction Potential Properties.

    Science.gov (United States)

    Ke, Yiling; Mitacek, Rachel M; Abraham, Anupam; Mafi, Gretchen G; VanOverbeke, Deborah L; DeSilva, Udaya; Ramanathan, Ranjith

    2017-09-06

    Mitochondria play a significant role in beef color. However, the role of oxidative stress in cytochrome c release and mitochondrial degradation is not clear. The objective was to determine the effects of display time on cytochrome c content and oxidation-reduction potential (ORP) of beef longissimus lumborum (LL) and psoas major (PM) muscles. PM discolored by day 3 compared with LL. On day 0, mitochondrial content and mitochondrial oxygen consumption were greater in PM than LL. However, mitochondrial content and oxygen consumption were lower (P stress can affect cytochrome c release and ORP changes.

  9. Tungsten oxide thin film exposed to low energy D and He plasma: evidence for a thermal enhancement of the erosion yield

    Science.gov (United States)

    Hijazi, Hussein; Martin, C.; Roubin, P.; Addab, Y.; Cabie, C.; Pardanaud, C.; Bannister, M.; Meyer, F.

    2017-10-01

    Nanocrystalline tungsten oxide thin films (25 nm - 250 nm thickness) produced by thermal oxidation of a tungsten substrate were exposed to low energy D and He plasma. Low energy D plasma exposure (11 eV/D+) of these films have resulted in the formation of a tungsten bronze (DxWO3) clearly observed by Raman microscopy. D plasma bombardment (4 1021 m-2) has also induced a color change of the oxide layer which is similar to the well-known electro-chromic effect and has been named ``plasma-chromic effect''. To unravel physical and chemical origins of the modifications observed under exposure, similar tungsten oxide films were also exposed to low energy helium plasma (20 eV/He+) . Due to the low fluence (4 1021 m-2) and low ion energy (20 eV), at room temperature, He exposure has induced only very few morphological and structural modifications. On the contrary, at 673 K, significant erosion is observed, which gives evidence for an unexpected thermal enhancement of the erosion yield. We present here new results concerning He beam exposures at low fluence (4 1021 m-2) varying the He+ energy from 20 eV to 320 eV to measure the tungsten oxide sputtering threshold energy. Detailed analyses before/after exposure to describe the D and He interaction with the oxide layer, its erosion and structural modification at the atomic and micrometer scale will be presented.

  10. Study of the Higgs boson discovery potential in the process pp{yields}Hqq, H{yields}{tau}{sup +}{tau}{sup -} with the ATLAS detector

    Energy Technology Data Exchange (ETDEWEB)

    Groh, Manfred

    2009-04-27

    The subject of this work is the evaluation of the discovery potential of the ATLAS detector at the Large Hadron Collider for the Standard Model Higgs boson in vector-boson fusion production and a subsequent decay into a {tau}-lepton pair. This is one of the most promising discovery channels of the Higgs boson in the low mass range, which is the mass range favored from precision measurements of the electroweak interaction. The decay modes where both {tau} leptons decay leptonically and where one {tau} lepton decays leptonically and the other one hadronically are studied in this thesis. The main objective was to investigate possible improvements upon earlier cut-based analyses by using additional discriminating variables as well as by applying multivariate analysis methods which take into account correlations between the variables. The variables are carefully selected in order to avoid correlations with the reconstructed invariant {tau}{tau} mass. In an intermediate step, the sequential signal selection cuts have been optimized for maximum signal significance. With this strategy, one can expect to discover the Higgs boson with {>=}5{sigma} significance in the mass range 115 GeV{<=} m{sub H}{<=}135 GeV with an integrated luminosity of 30 fb{sup -1} corresponding to the first three years of ATLAS operation. The maximum signal significance of 5.9{sigma} is obtained for a Higgs mass of 120 GeV. Significant further improvement was found with multivariate selection methods. The best results are obtained with an Artificial Neural Network algorithm. The mass range for the {>=}5{sigma} Higgs discovery with 30 fb{sup -1} is extended to 110 GeV with a maximum signal significance of 6.5 {sigma} at m{sub H}=125 GeV. Systematic uncertainties are studied in detail for both methods and are included in the above predictions of the signal significance. The largest uncertainty is due to the jet energy scale. In the case of using only Monte Carlo simulations for estimating the

  11. Regional annual water yield from forest lands and its response to potential deforestation across the southeastern United States

    Science.gov (United States)

    Ge Sun; Steve G. McNulty; J. Lu; Devendra M. Amatya; Y. Liang; R.K. Kolka

    2005-01-01

    Regional water yield at a meso-scale can be estimated as the difference between precipitation input and evapotranspiration output. Forest water yield from the southeastern US varies greatly both in space and time. Because of the hot climate and high evapotranspiration, less than half of the annual precipitation that falls on forest lands is available for stream flow...

  12. [Comparison of potential yield and resource utilization efficiency of main food crops in three provinces of Northeast China under climate change].

    Science.gov (United States)

    Wang, Xiao-yu; Yang, Xiao-guang; Sun, Shuang; Xie, Wen-juan

    2015-10-01

    Based on the daily data of 65 meteorological stations from 1961 to 2010 and the crop phenology data in the potential cultivation zones of thermophilic and chimonophilous crops in Northeast China, the crop potential yields were calculated through step-by-step correction method. The spatio-temporal distribution of the crop potential yields at different levels was analyzed. And then we quantified the limitations of temperature and precipitation on the crop potential yields and compared the differences in the climatic resource utilization efficiency. The results showed that the thermal potential yields of six crops (including maize, rice, spring wheat, sorghum, millet and soybean) during the period 1961-2010 deceased from west to east. The climatic potential yields of the five crops (spring wheat not included) were higher in the south than in the north. The potential yield loss rate due to temperature limitations of the six crops presented a spatial distribution pattern and was higher in the east than in the west. Among the six main crops, the yield potential loss rate due to temperature limitation of the soybean was the highest (51%), and those of the other crops fluctuated within the range of 33%-41%. The potential yield loss rate due to water limitation had an obvious regional difference, and was high in Songnen Plain and Changbai Mountains. The potential yield loss rate of spring wheat was the highest (50%), and those of the other four rainfed crops fluctuated within the range of 8%-10%. The solar energy utilization efficiency of the six main crops ranged from 0.9% to 2.7%, in the order of maize> sorghum>rice>millet>spring wheat>soybean. The precipitation utilization efficiency of the maize, sorghum, spring wheat, millet and soybean under rainfed conditions ranged from 8 to 35 kg . hm-2 . mm-1, in the order of maize>sorghum>spring wheat>millet>soybean. In those areas with lower efficiency of solar energy utilization and precipitation utilization, such as Changbai

  13. Oxidative potential of particulate matter 2.5 as predictive indicator of cellular stress

    International Nuclear Information System (INIS)

    Crobeddu, Bélinda; Aragao-Santiago, Leticia; Bui, Linh-Chi; Boland, Sonja; Baeza Squiban, Armelle

    2017-01-01

    Particulate air pollution being recognized to be responsible for short and long term health effects, regulations for particulate matter with an aerodynamic diameter less than 2.5 (PM 2.5 ) are more and more restrictive. PM 2.5 regulation is based on mass without taking into account PM 2.5 composition that drives toxicity. Measurement of the oxidative potential (OP) of PM could be an additional PM indicator that would encompass the PM components involved in oxidative stress, the main mechanism of PM toxicity. We compared different methods to evaluate the intrinsic oxidative potential of PM 2.5 sampled in Paris and their ability to reflect the oxidative and inflammatory response in bronchial epithelial cells used as relevant target organ cells. The dithiothreitol depletion assay, the antioxidant (ascorbic acid and glutathione) depletion assay (OP AO ), the plasmid scission assay and the dichlorofluorescein (DCFH) oxidation assay used to characterize the OP of PM 2.5 (10–100 μg/mL) provided positive results of different magnitude with all the PM 2.5 samples used with significant correlation with different metals such as Cu and Zn as well as total polyaromatic hydrocarbons and the soluble organic fraction. The OP AO assay showed the best correlation with the production of intracellular reactive oxygen species by NCI-H292 cell line assessed by DCFH oxidation and with the expression of anti-oxidant genes (superoxide dismutase 2, heme-oxygenase-1) as well as the proinflammatory response (Interleukin 6) when exposed from 1 to 10 μg/cm 2 . The OP AO assay appears as the most prone to predict the biological effect driven by PM 2.5 and related to oxidative stress. - Highlights: • 5 Acellular assays were used to compare the intrinsic oxidative potential (OP) of PM. • The amount of ROS generation in bronchial cells is particle dependent. • Particles induce the expression of anti-oxidant and proinflammatory genes. • Biological effects correlates with OP assay

  14. Set potential regulation reveals additional oxidation peaks of Geobacter sulfurreducens anodic biofilms

    KAUST Repository

    Zhu, Xiuping; Yates, Matthew D.; Logan, Bruce E.

    2012-01-01

    larger range of set potentials was used to acclimate electroactive biofilms. The potentials of oxidation peaks obtained with G. sulfurreducens biofilms acclimated at 0.60 V (vs. Ag/AgCl) were different from those that developed at - 0.46 V, and both

  15. Thiol dioxygenase turnover yields benzothiazole products from 2-mercaptoaniline and O2-dependent oxidation of primary alcohols.

    Science.gov (United States)

    Morrow, William P; Sardar, Sinjinee; Thapa, Pawan; Hossain, Mohammad S; Foss, Frank W; Pierce, Brad S

    2017-10-01

    Thiol dioxygenases are non-heme mononuclear iron enzymes that catalyze the O 2 -dependent oxidation of free thiols (-SH) to produce the corresponding sulfinic acid (-SO 2 - ). Previous chemical rescue studies identified a putative Fe III -O 2 - intermediate that precedes substrate oxidation in Mus musculus cysteine dioxygenase (Mm CDO). Given that a similar reactive intermediate has been identified in the extradiol dioxygenase 2, 3-HCPD, it is conceivable that these enzymes share other mechanistic features with regard to substrate oxidation. To explore this possibility, enzymatic reactions with Mm CDO (as well as the bacterial 3-mercaptopropionic acid dioxygenase, Av MDO) were performed using a substrate analogue (2-mercaptoaniline, 2ma). This aromatic thiol closely approximates the catecholic substrate of homoprotocatechuate of 2, 3-HPCD while maintaining the 2-carbon thiol-amine separation preferred by Mm CDO. Remarkably, both enzymes exhibit 2ma-gated O 2 -consumption; however, none of the expected products for thiol dioxygenase or intra/extradiol dioxygenase reactions were observed. Instead, benzothiazoles are produced by the condensation of 2ma with aldehydes formed by an off-pathway oxidation of primary alcohols added to aqueous reactions to solubilize the substrate. The observed oxidation of 1º-alcohols in 2ma-reactions is consistent with the formation of a high-valent intermediate similar to what has been reported for cytochrome P450 and mononuclear iron model complexes. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Enhanced yield of phenolic extracts from banana peels (Musa acuminata Colla AAA) and cinnamon barks (Cinnamomum varum) and their antioxidative potentials in fish oil.

    Science.gov (United States)

    Anal, Anil Kumar; Jaisanti, Sirorat; Noomhorm, Athapol

    2014-10-01

    The bioactive compounds of banana peels and cinnamon barks were extracted by vacuum microwave and ultrasonic-assisted extraction methods at pre-determined temperatures and times. These methods enhance the yield extracts in shorter time. The highest yields of both extracts were obtained from the conditions which employed the highest temperature and the longest time. The extracts' yield from cinnamon bark method was higher by ultrasonic than vacuum microwave method, while vacuum microwave method gave higher extraction yield from banana peel than ultrasonic method. The phenolic contents of cinnamon bark and banana peel extracts were 467 and 35 mg gallic acid equivalent/g extract, respectively. The flavonoid content found in banana peel and cinnamon bark extracts were 196 and 428 mg/g quercetin equivalent, respectively. In addition, it was found that cinnamon bark gave higher 2,2-Diphenyl-1-1 picryhydrazyl (DPPH) radical scavenging activity and total antioxidant activity (TAA). The antioxidant activity of the extracts was analyzed by measuring the peroxide and p-anisidine values after oxidation of fish oils, stored for a month (30 days) at 25 °C and showed lesser peroxide and p-anisidine values in the fish oils containing the sample extracts in comparison to the fish oil without containing any extract. The banana peel and cinnamon extracts had shown the ability as antioxidants to prevent the oxidation of fish oil and might be considered as rich sources of natural antioxidant.

  17. Potential Impacts of two SO2 oxidation pathways on regional sulfate concentrations: acqueous-hase oxidation by NO2 and gas-phase oxidation by Stabilized Criegee Intermediates

    Science.gov (United States)

    We examine the potential impacts of two additional sulfate production pathways using the Community Multiscale Air Quality modeling system. First we evaluate the impact of the aqueous-phase oxidation of S(IV) by nitrogen dioxide using two published rate constants, differing by 1-2...

  18. A series of inorganic solid nitrogen sources for the synthesis of metal nitride clusterfullerenes: the dependence of production yield on the oxidation state of nitrogen and counter ion.

    Science.gov (United States)

    Liu, Fupin; Guan, Jian; Wei, Tao; Wang, Song; Jiao, Mingzhi; Yang, Shangfeng

    2013-04-01

    A series of nitrogen-containing inorganic solid compounds with variable oxidation states of nitrogen and counter ions have been successfully applied as new inorganic solid nitrogen sources toward the synthesis of Sc-based metal nitride clusterfullerenes (Sc-NCFs), including ammonium salts [(NH4)xH(3-x)PO4 (x = 0-2), (NH4)2SO4, (NH4)2CO3, NH4X (X = F, Cl), NH4SCN], thiocyanate (KSCN), nitrates (Cu(NO3)2, NaNO3), and nitrite (NaNO2). Among them, ammonium phosphates ((NH4)xH(3-x)PO4, x = 1-3) and ammonium thiocyanate (NH4SCN) are revealed to behave as better nitrogen sources than others, and the highest yield of Sc-NCFs is achieved when NH4SCN was used as a nitrogen source. The optimum molar ratio of Sc2O3:(NH4)3PO4·3H2O:C and Sc2O3:NH4SCN:C has been determined to be 1:2:15 and 1:3:15, respectively. The thermal decomposition products of these 12 inorganic compounds have been discussed in order to understand their different performances toward the synthesis of Sc-NCFs, and accordingly the dependence of the production yield of Sc-NCFs on the oxidation state of nitrogen and counter ion is interpreted. The yield of Sc3N@C80 (I(h) + D(5h)) per gram Sc2O3 by using the N2-based group of nitrogen sources (thiocyanate, nitrates, and nitrite) is overall much lower than those by using gaseous N2 and NH4SCN, indicating the strong dependence of the yield of Sc-NCFs on the oxidation state of nitrogen, which is attributed to the "in-situ" redox reaction taking place for the N2-based group of nitrogen sources during discharging. For NH3-based group of nitrogen sources (ammonium salts) which exhibits a (-3) oxidation states of nitrogen, their performance as nitrogen sources is found to be sensitively dependent on the anion, and this is understood by considering their difference on the thermal stability and/or decomposition rate. Contrarily, for the N2-based group of nitrogen sources, the formation of Sc-NCFs is independent to both the oxidation state of nitrogen (+3 or +5) and the

  19. Fermi Potential across Working Solid Oxide Cells with Zirconia or Ceria Electrolytes

    DEFF Research Database (Denmark)

    Jacobsen, Torben; Chatzichristodoulou, Christodoulos; Mogensen, Mogens Bjerg

    2014-01-01

    A solid electrolyte will always possess a finite electronic conductivity, in particular electrolytes like doped ceria that easily get reduced and become mixed ionic and electronic conductors. This given rise too high leak currents through the solid oxide cell (SOC). Especially, problems have been...... driving the O2-ions is not the Fermi potential, which is the potential of the electrons, but the Galvani potential (or inner potential) (1). The concepts of potentials describing the electrical situation of a solid electrolyte is shown i Fig. 1, and an example of the Fermi potential (π) and Galvani...

  20. On-farm yield potential of local seed watermelon landraces under heat- and drought-prone conditions in Mali

    DEFF Research Database (Denmark)

    Nantoume, Aminata Dolo; Christiansen, Jørgen Lindskrog; Andersen, Sven Bode

    2012-01-01

    On-farm yield experiments were carried out in the Tombouctou region of Mali in 2009/10 under heat- and drought-prone desert conditions with three local landraces of seed-type watermelons. The landraces, named Fombou, Kaneye and Musa Musa by the farmers, exhibited distinct characteristics for fruit...... responsive. The yields obtained suggest that these local landraces of watermelon are valuable plant genetic resources for securing food supply in arid, heat- and drought-prone areas....

  1. Assessing the influence of NOx concentrations and relative humidity on secondary organic aerosol yields from α-pinene photo-oxidation through smog chamber experiments and modelling calculations

    Science.gov (United States)

    Stirnweis, Lisa; Marcolli, Claudia; Dommen, Josef; Barmet, Peter; Frege, Carla; Platt, Stephen M.; Bruns, Emily A.; Krapf, Manuel; Slowik, Jay G.; Wolf, Robert; Prévôt, Andre S. H.; Baltensperger, Urs; El-Haddad, Imad

    2017-04-01

    Secondary organic aerosol (SOA) yields from the photo-oxidation of α-pinene were investigated in smog chamber (SC) experiments at low (23-29 %) and high (60-69 %) relative humidity (RH), various NOx / VOC ratios (0.04-3.8) and with different aerosol seed chemical compositions (acidic to neutralized sulfate-containing or hydrophobic organic). A combination of a scanning mobility particle sizer and an Aerodyne high-resolution time-of-flight aerosol mass spectrometer was used to determine SOA mass concentration and chemical composition. We used a Monte Carlo approach to parameterize smog chamber SOA yields as a function of the condensed phase absorptive mass, which includes the sum of OA and the corresponding bound liquid water content. High RH increased SOA yields by up to 6 times (1.5-6.4) compared to low RH. The yields at low NOx / VOC ratios were in general higher compared to yields at high NOx / VOC ratios. This NOx dependence follows the same trend as seen in previous studies for α-pinene SOA. A novel approach of data evaluation using volatility distributions derived from experimental data served as the basis for thermodynamic phase partitioning calculations of model mixtures in this study. These calculations predict liquid-liquid phase separation into organic-rich and electrolyte phases. At low NOx conditions, equilibrium partitioning between the gas and liquid phases can explain most of the increase in SOA yields observed at high RH, when in addition to the α-pinene photo-oxidation products described in the literature, fragmentation products are added to the model mixtures. This increase is driven by both the increase in the absorptive mass and the solution non-ideality described by the compounds' activity coefficients. In contrast, at high NOx, equilibrium partitioning alone could not explain the strong increase in the yields with RH. This suggests that other processes, e.g. reactive uptake of semi-volatile species into the liquid phase, may occur and be

  2. Role of groundwater oxidation potential and radiolysis on waste glass performance in crystalline repository environments

    International Nuclear Information System (INIS)

    Jantzen, C.M.; Bibler, N.E.

    1985-01-01

    Laboratory experiments have shown that groundwater conditions in a Stripa granite repository will be as reducing as those in a basalt repository. The final oxidation potential (Eh) at 70 0 C for Stripa groundwater deaerated and equilibrated with crystalline granite was -0.45V. In contrast, the oxidation potential at 60 0 C for Grande Ronde groundwater equilibrated with basalt was -0.40V. The reducing groundwater conditions were found to slightly decrease the time-dependent release of soluble components from the waste glass. Spectrophotometric analysis of the equilibrated groundwaters indicated the presence of Fe 2+ confirming that the Fe 2+ /Fe 3+ couple is controlling the oxidation potential. It was also shown that in the alkaline pH regime of these groundwaters the iron species are primarily associated with x-ray amorphous precipitates in the groundwater. Gamma radiolysis in the absence of waste glass and in the absence of oxygen further reduces the oxidation potential of both granitic and basaltic groundwaters. The effect is more pronounced in the basaltic groundwater. The mechanism for this decrease is under investigation but appears related to the reactive amorphous precipitate. The results of these tests suggest that H 2 may not escape from the repository system as postulated and that radiolysis may not cause the groundwaters to become oxidizing in a crystalline repository when abundant Fe 2+ species are present. 23 refs., 3 figs., 3 tabs

  3. A comparative study of quantum yield and electrical energy per order (E(Eo)) for advanced oxidative decolourisation of reactive azo dyes by UV light.

    Science.gov (United States)

    Muruganandham, M; Selvam, K; Swaminathan, M

    2007-06-01

    This paper evaluates the quantum yield and electrical energy per order (E(Eo)) efficiency of Reactive Orange 4 (RO4) and Reactive Yellow 14 (RY14) azo dyes by three advanced oxidation processes (AOPs). Both dyes were completely decolourised by all these processes. The relative decolourisation efficiencies of these processes were in the following order: Fe(2+)/H(2)O(2)/UV>UV/TiO(2)>UV/H(2)O(2). The low efficiency of UV/H(2)O(2) process is mainly due to low UV absorption by hydrogen peroxide at the 365nm. The figure of merit E(Eo) values showed that UV/H(2)O(2) process consumes more electrical energy than the other two processes. The electrical energy consumption is in the following order: UV/H(2)O(2)>UV/TiO(2)>Fe(2+)/H(2)O(2)/UV. At low initial dye concentration higher quantum yield was observed in UV/TiO(2) process, whereas in photo-Fenton process higher quantum yield was observed at high initial dye concentration. The structure of dye molecule also influences the quantum yield and E(Eo) value.

  4. A comparative study of quantum yield and electrical energy per order (E Eo) for advanced oxidative decolourisation of reactive azo dyes by UV light

    International Nuclear Information System (INIS)

    Muruganandham, M.; Selvam, K.; Swaminathan, M.

    2007-01-01

    This paper evaluates the quantum yield and electrical energy per order (E Eo ) efficiency of Reactive Orange 4 (RO4) and Reactive Yellow 14 (RY14) azo dyes by three advanced oxidation processes (AOPs). Both dyes were completely decolourised by all these processes. The relative decolourisation efficiencies of these processes were in the following order: Fe 2+ /H 2 O 2 /UV > UV/TiO 2 > UV/H 2 O 2 . The low efficiency of UV/H 2 O 2 process is mainly due to low UV absorption by hydrogen peroxide at the 365 nm. The figure of merit E Eo values showed that UV/H 2 O 2 process consumes more electrical energy than the other two processes. The electrical energy consumption is in the following order: UV/H 2 O 2 > UV/TiO 2 > Fe 2+ /H 2 O 2 /UV. At low initial dye concentration higher quantum yield was observed in UV/TiO 2 process, whereas in photo-Fenton process higher quantum yield was observed at high initial dye concentration. The structure of dye molecule also influences the quantum yield and E Eo value

  5. Oxidation potentials, Gibbs energies, enthalpies and entropies of actinide ions in aqueous solutions

    International Nuclear Information System (INIS)

    1977-01-01

    The values of the Gibbs energy, enthalpy, and entropy of different actinide ions, thermodynamic characteristics of the processes of hydration of these ions, and the presently known ionization potentials of actinides are given. The enthalpy and entropy components of the oxidation potentials of actinide elements are considered. The curves of the dependence of the Gibbs energy of ion formation on the atomic number of the element and the Frost diagrams are analyzed. The diagram proposed by Frost represents the graphical dependence of the Gibbs energy of hydrated ions on the degree of oxidation of the element. Using the Frost diagram it is easy to establish whether a given ion is stable to disproportioning

  6. Oxidative stress in sickle cell disease; pathophysiology and potential implications for disease management.

    Science.gov (United States)

    Nur, Erfan; Biemond, Bart J; Otten, Hans-Martin; Brandjes, Dees P; Schnog, John-John B

    2011-06-01

    Sickle cell disease (SCD) is a hemoglobinopathy characterized by hemolytic anemia, increased susceptibility to infections and vaso-occlusion leading to a reduced quality of life and life expectancy. Oxidative stress is an important feature of SCD and plays a significant role in the pathophysiology of hemolysis, vaso-occlusion and ensuing organ damage in sickle cell patients. Reactive oxygen species (ROS) and the (end-)products of their oxidative reactions are potential markers of disease severity and could be targets for antioxidant therapies. This review will summarize the role of ROS in SCD and their potential implication for SCD management. Copyright © 2011 Wiley-Liss, Inc.

  7. Effect of sea salt irrigation on plant growth, yield potential and some biochemical attributes of carissa carandas

    International Nuclear Information System (INIS)

    Tayyab, A.

    2016-01-01

    Carissa carandas (varn. Karonda) is an edible and medicinal plant having ability to grow in saline and water deficit conditions, however, little is known about its salinity tolerance. Therefore, the effect of salinity on vegetative (height and volume), reproductive (number of flowers and number, size and weight of fruits) and some biochemical parameters (leaf pigments, ions, soluble sugars, proteins, and phenols) of C. carandas were studied. Plants were grown in drum pot culture and irrigated with non-saline or saline water of 0.6% and 0.8% sea salt concentrations, for a period of 30 months. Results showed that, plant height, and canopy volume decreased with increasing salinity. The chlorophyll contents and chlorophyll a/b ratio followed the similar trend as for growth, however, carotenoids increased at 0.6% sea salt and subsequently decreased in higher salinity. Unchanged soluble sugar and protein content at 0.6% sea salt, as compared to control, could be attributed to leaf osmotic adjustments which decreased with further increase in salinity. Linear increase in soluble phenols and carotenoid/chlorophyll ratio indicating a protective strategy of C. carandas to minimize photo-damage. Besides increasing Na+ and decreasing K+ contents, plant seemed to maintain K+/Na+ ratio (above 1), especially at 0.6 sea salt, which disturbed at higher salinity. Salinity adversely affected reproductive growth of C. carandas where, production of flowers, and fruits were significantly reduced. In addition, fresh and dry weights of fruits decreased with increasing salinity, but salinity did not affect fruit length and diameter. Present study provides basic information related to plant growth, fruit yield and some biochemical attributes, which suggest that C. carandas is moderately salt tolerant plant. This plant showed potential to grow on saline marginal lands using brackish water irrigation and provide biomass for edible and medicinal purposes. However, in-depth analysis of field and

  8. Accelerated aging in schizophrenia patients: the potential role of oxidative stress.

    Science.gov (United States)

    Okusaga, Olaoluwa O

    2014-08-01

    Several lines of evidence suggest that schizophrenia, a severe mental illness characterized by delusions, hallucinations and thought disorder is associated with accelerated aging. The free radical (oxidative stress) theory of aging assumes that aging occurs as a result of damage to cell constituents and connective tissues by free radicals arising from oxygen-associated reactions. Schizophrenia has been associated with oxidative stress and chronic inflammation, both of which also appear to reciprocally induce each other in a positive feedback manner. The buildup of damaged macromolecules due to increased oxidative stress and failure of protein repair and maintenance systems is an indicator of aging both at the cellular and organismal level. When compared with age-matched healthy controls, schizophrenia patients have higher levels of markers of oxidative cellular damage such as protein carbonyls, products of lipid peroxidation and DNA hydroxylation. Potential confounders such as antipsychotic medication, smoking, socio-economic status and unhealthy lifestyle make it impossible to solely attribute the earlier onset of aging-related changes or oxidative stress to having a diagnosis of schizophrenia. Regardless of whether oxidative stress can be attributed solely to a diagnosis of schizophrenia or whether it is due to other factors associated with schizophrenia, the available evidence is in support of increased oxidative stress-induced cellular damage of macromolecules which may play a role in the phenomenon of accelerated aging presumed to be associated with schizophrenia.

  9. Theoretical study of ionization and one-electron oxidation potentials of N-heterocyclic compounds.

    Science.gov (United States)

    Sviatenko, Liudmyla K; Gorb, Leonid; Hill, Frances C; Leszczynski, Jerzy

    2013-05-15

    A number of density functionals was utilized to predict gas-phase adiabatic ionization potentials (IPs) for nitrogen-rich heterocyclic compounds. Various solvation models were applied to the calculation of difference in free energies of solvation of oxidized and reduced forms of heterocyclic compounds in acetonitrile (AN) for correct reproduction of their standard oxidation potentials. We developed generally applicable protocols that could successfully predict the gas-phase adiabatic ionization potentials of nitrogen-rich heterocyclic compounds and their standard oxidation potentials in AN. This approach is supported by a MPW1K/6-31+G(d) level of theory which uses SMD(UA0) approximation for estimation of solvation energy of neutral molecules and PCM(UA0) model for ionized ones. The mean absolute derivation (MAD) and root mean square error (RMSE) of the current theoretical models for IP are equal to 0.22 V and 0.26, respectively, and for oxidation potentials MAD = 0.13 V and RMSE = 0.17. Copyright © 2013 Wiley Periodicals, Inc.

  10. Benthic Ammonia Oxidizers Differ in Community Structure and Biogeochemical Potential Across a Riverine Delta

    Directory of Open Access Journals (Sweden)

    Julian eDamashek

    2015-01-01

    Full Text Available Nitrogen pollution in coastal zones is a widespread issue, particularly in ecosystems with urban or agricultural watersheds. California’s Sacramento-San Joaquin Delta, at the landward reaches of San Francisco Bay, is highly impacted by both agricultural runoff and sewage effluent, leading to chronically high nutrient loadings. In particular, the massive discharge of ammonium into the Sacramento River has altered this ecosystem by increasing ammonium concentrations and thus changing the stoichiometry of inorganic nitrogen stocks, with potential effects throughout the food web. To date, however, there has been little research examining N biogeochemistry or N-cycling microbial communities in this system. We report the first data on benthic ammonia-oxidizing microbial communities and potential nitrification rates for the Sacramento-San Joaquin Delta, focusing on the functional gene amoA (encoding the α-subunit of ammonia monooxygenase. There were stark regional differences in ammonia-oxidizing communities, with ammonia-oxidizing bacteria (AOB outnumbering ammonia-oxidizing archaea (AOA only in the ammonium-rich Sacramento River. High potential nitrification rates in the Sacramento River suggested these communities may be capable of oxidizing significant amounts of ammonium, compared to the San Joaquin River and the upper reaches of San Francisco Bay. Gene diversity also showed regional patterns, as well as phylogenetically unique ammonia oxidizers in the Sacramento River. The community structure and biogeochemical function of benthic ammonia oxidizers appears related to nutrient loadings. Unraveling the microbial ecology and biogeochemistry of N cycling pathways is a critical step toward understanding how such ecosystems respond to the changing environmental conditions wrought by human development and climate change.

  11. Will C3 crops enhanced with the C4 CO2-concentrating mechanism live up to their full potential (yield)?

    NARCIS (Netherlands)

    Driever, S.M.; Kromdijk, J.

    2013-01-01

    Sustainably feeding the world’s growing population in future is a great challenge and can be achieved only by increasing yield per unit land surface. Efficiency of light interception and biomass partitioning into harvestable parts (harvest index) has been improved substantially via plant breeding in

  12. Spatial and harvesting influence on growth, yield, quality and economic potential of Kalmegh (Andrographis paniculata Wall Ex. Nees

    Directory of Open Access Journals (Sweden)

    Sanjeev Kumar

    2013-08-01

    Full Text Available Andrographis paniculata, commonly known as Kalmegh, is used both in Ayurvedic and Unani system of medicines because of its immunological, antibacterial and hepatoprotective properties. This study was carried out to investigate the influence of four harvesting times (120,135,150 days after planting and at seed maturity and four planting distances (30×15, 30×10, 20×15 and 20×10 cm on growth, dry herbage biomass, seed yield and quality traits of Andrographis paniculata at CCS Haryana Agricultural University, Hisar, India in the two years 2005 and 2006. The treatments were laid out in a split plot design with three replications. The maximum values for dry herbage biomass yield (5.14 t ha^(-1, net returns (760.00 EUR ha^(-1, B:C ratio (2.59, andrographolide content (2.63% and total yield (135.00 kg ha^(-1 were detected 135 days after planting with an optimum planting distance of 30×15 cm. However, the maximum iron content was estimated 120 days after planting. The highest dry herbage (4.58 t ha^(-1 and maximum seed yield (19.7 kg ha^(-1 were registered at plants that were lined out with a distance of 20×10 cm.

  13. Identification of cocoa trees combining high yield potential and resistance to diseases in segregating progenies In Ecuador

    Science.gov (United States)

    Diseases and low yielding planting material are the main factors limiting production of “fine” or “flavour” cocoa in Ecuador. This makes it necessary to develop modern varieties capable of overcoming these limitations. During the 1960s and 1970s INIAP tested several progenies from selected crosses...

  14. Organic nitrate and secondary organic aerosol yield from NO3 oxidation of β-pinene evaluated using a gas-phase kinetics/aerosol partitioning model

    Directory of Open Access Journals (Sweden)

    H.-P. Dorn

    2009-02-01

    Full Text Available The yields of organic nitrates and of secondary organic aerosol (SOA particle formation were measured for the reaction NO3+β-pinene under dry and humid conditions in the atmosphere simulation chamber SAPHIR at Research Center Jülich. These experiments were conducted at low concentrations of NO3 (NO3+N2O5pvap~5×10−6 Torr (6.67×10−4 Pa, which constrains speculation about the oxidation mechanism and chemical identity of the organic nitrate. Once formed the SOA in this system continues to evolve, resulting in measurable aerosol volume decrease with time. The observations of high aerosol yield from NOx-dependent oxidation of monoterpenes provide an example of a significant anthropogenic source of SOA from biogenic hydrocarbon precursors. Estimates of the NO3+β-pinene SOA source strength for California and the globe indicate that NO3 reactions with monoterpenes are likely an important source (0.5–8% of the global total of organic aerosol on regional and global scales.

  15. Potential of deficit irrigation, irrigation cut-offs, and crop thinning to maintain yield and fruit quality with less water in northern highbush blueberry

    Science.gov (United States)

    Drought and mandatory water restrictions are limiting the availability of irrigation water in many important blueberry growing regions, including Oregon, Washington, and California. New strategies are needed to maintain yield and fruit quality with less water. Three potential options, including defi...

  16. Quality of white cabbage yield and potential risk of ground water nitrogen pollution, as affected by nitrogen fertilisation and irrigation practices.

    Science.gov (United States)

    Maršić, Nina Kacjan; Sturm, Martina; Zupanc, Vesna; Lojen, Sonja; Pintar, Marina

    2012-01-15

    The effect of different fertilisation (broadcast solid NPK application and fertigation with water-soluble fertiliser) and irrigation practices (sprinkler and drip irrigation) on yield, the nitrate content in cabbage (Brassica oleracea var. capitata L.) and the cabbage N uptake was detected, in order to assess the potential risk for N losses, by cultivation on sandy-loam soil. The N rate applied on the plots was 200 kg N ha(-1). The highest yield (93 t ha(-1)) and nitrate content (1256 mg kg(-1) DW) were found with treatments using broadcast fertilisation and sprinkler irrigation. On those plots the negative N balance (-30 kg N ha(-1)) was recorded, which comes mainly from the highest crop N uptake (234 kg N ha(-1)) indicating the lowest potential for N losses. In terms of yield quality and the potential risk for N losses, broadcast fertilisation combined with sprinkler irrigation proved to be the most effective combination among the tested practices under the given experimental conditions. The importance of adequate irrigation is also evident, namely in plots on which 50% drip irrigation was applied, the lowest yield was detected and according to the positive N balance, a higher potential for N losses is expected. Copyright © 2011 Society of Chemical Industry.

  17. Viral induced oxidative and inflammatory response in Alzheimer's disease pathogenesis with identification of potential drug candidates: A systematic review using systems biology approach.

    Science.gov (United States)

    Talwar, Puneet; Gupta, Renu; Kushwaha, Suman; Agarwal, Rachna; Saso, Luciano; Kukreti, Shrikant; Kukreti, Ritushree

    2018-04-19

    Alzheimer's disease (AD) is genetically complex with multifactorial etiology. Here, we aim to identify the potential viral pathogens leading to aberrant inflammatory and oxidative stress response in AD along with potential drug candidates using systems biology approach. We retrieved protein interactions of amyloid precursor protein (APP) and tau protein (MAPT) from NCBI and genes for oxidative stress from NetAge, for inflammation from NetAge and InnateDB databases. Genes implicated in aging were retrieved from GenAge database and two GEO expression datasets. These genes were individually used to create protein-protein interaction network using STRING database (score≥0.7). The interactions of candidate genes with known viruses were mapped using virhostnet v2.0 database. Drug molecules targeting candidate genes were retrieved using the Drug-Gene Interaction Database (DGIdb). Data mining resulted in 2095 APP, 116 MAPT, 214 oxidative stress, 1269 inflammatory genes. After STRING PPIN analysis, 404 APP, 109 MAPT, 204 oxidative stress and 1014 inflammation related high confidence proteins were identified. The overlap among all datasets yielded eight common markers (AKT1, GSK3B, APP, APOE, EGFR, PIN1, CASP8 and SNCA). These genes showed association with hepatitis C virus (HCV), Epstein-Barr virus (EBV), human herpes virus 8 and Human papillomavirus (HPV). Further, screening of drugs targeting candidate genes, and possessing anti-inflammatory property, antiviral activity along with suggested role in AD pathophysiology yielded 12 potential drug candidates. Our study demonstrated the role of viral etiology in AD pathogenesis by elucidating interaction of oxidative stress and inflammation causing candidate genes with common viruses along with the identification of potential AD drug candidates. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  18. Calculated ionisation potentials to determine the oxidation of vanillin precursors by lignin peroxidase.

    NARCIS (Netherlands)

    Have, ten R.; Rietjens, I.M.C.M.; Hartmans, S.; Swarts, H.J.; Field, J.A.

    1998-01-01

    In view of the biocatalytic production of vanillin, this research focused on the lignin peroxidase (LiP) catalysed oxidation of naturally occurring phenolic derivatives: O-methyl ethers, O-acetyl esters, and O-glucosyl ethers. The ionisation potential (IP) of a series of model compounds was

  19. ANAEROBIC DDT BIOTRANSFORMATION: ENHANCEMENT BY APPLICATION OF SURFACTANTS AND LOW OXIDATION REDUCTION POTENTIAL

    Science.gov (United States)

    Enhancement of anaerobic DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane) biotransformation by mixed cultures was studied with application of surfactants and oxidation reduction potential reducing agents. Without amendments, DDT transformation resulted mainly in the pr...

  20. Oxygen Distribution and Potential Ammonia Oxidation in Floating, Liquid Manure Crusts

    DEFF Research Database (Denmark)

    Nielsen, Daniel Aagren; Nielsen, Lars Peter; Schramm, Andreas

    2010-01-01

     availability. In old natural crusts total potential NH3 oxidation rates were similar to reported fluxes of NH3 from slurry without surface crust. These results indicate that old, natural surface crusts may develop into a porous matrix with high O2 availability that harbors an active population of aerobic...

  1. A Classical Potential to Model the Adsorption of Biological Molecules on Oxidized Titanium Surfaces.

    Science.gov (United States)

    Schneider, Julian; Ciacchi, Lucio Colombi

    2011-02-08

    The behavior of titanium implants in physiological environments is governed by the thin oxide layer that forms spontaneously on the metal surface and mediates the interactions with adsorbate molecules. In order to study the adsorption of biomolecules on titanium in a realistic fashion, we first build up a model of an oxidized Ti surface in contact with liquid water by means of extensive first-principles molecular dynamics simulations. Taking the obtained structure as reference, we then develop a classical potential to model the Ti/TiOx/water interface. This is based on the mapping with Coulomb and Lennard-Jones potentials of the adsorption energy landscape of single water and ammonia molecules on the rutile TiO2(110) surface. The interactions with arbitrary organic molecules are obtained via standard combination rules to established biomolecular force fields. The transferability of our potential to the case of organic molecules adsorbing on the oxidized Ti surface is checked by comparing the classical potential energy surfaces of representative systems to quantum mechanical results at the level of density functional theory. Moreover, we calculate the heat of immersion of the TiO2 rutile surface and the detachment force of a single tyrosine residue from steered molecular dynamics simulations, finding good agreement with experimental reference data in both cases. As a first application, we study the adsorption behavior of the Arg-Gly-Asp (RGD) peptide on the oxidized titanium surface, focusing particularly on the calculation of the free energy of desorption.

  2. COMPUTATIONAL ELECTROCHEMISTRY: AQUEOUS ONE-ELECTRON OXIDATION POTENTIALS FOR SUBSTITUTED ANILINES

    Science.gov (United States)

    Semiempirical molecular orbital theory and density functional theory are used to compute one-electron oxidation potentials for aniline and a set of 21 mono- and di-substituted anilines in aqueous solution. Linear relationships between theoretical predictions and experiment are co...

  3. Corrigendum to "Sinusoidal potential cycling operation of a direct ethanol fuel cell to improving carbon dioxide yields" [J. Power Sources 268 (5 December 2014) 439-442

    Science.gov (United States)

    Majidi, Pasha; Pickup, Peter G.

    2016-09-01

    The authors regret that Equation (5) is incorrect and has resulted in errors in Fig. 4 and the efficiencies stated on p. 442. The corrected equation, figure and text are presented below. In addition, the title should be 'Sinusoidal potential cycling operation of a direct ethanol fuel cell to improve carbon dioxide yields', and the reversible cell potential quoted on p. 441 should be 1.14 V. The authors would like to apologise for any inconvenience caused.

  4. Water Content Effect on Oxides Yield in Gas and Liquid Phase Using DBD Arrays in Mist Spray

    International Nuclear Information System (INIS)

    Chen Bingyan; Zhu Changping; He Xiang; Yin Cheng; Fei Juntao; Wang Yuan; Jiang Yongfeng; Chen Longwei; Gao Yuan; Han Qingbang

    2016-01-01

    Electric discharge in and in contact with water can accompany ultraviolet (UV) radiation and electron impact, which can generate a large number of active species such as hydroxyl radicals (OH), oxygen radical (O), ozone (O 3 ) and hydrogen peroxide (H 2 O 2 ). In this paper, a nonthermal plasma processing system was established by means of dielectric barrier discharge (DBD) arrays in water mist spray. The relationship between droplet size and water content was examined, and the effects of the concentrations of oxides in both treated water and gas were investigated under different water content and discharge time. The relative intensity of UV spectra from DBD in water mist was a function of water content. The concentrations of both O 3 and nitrogen dioxide (NO 2 ) in DBD room decreased with increasing water content. Moreover, the concentrations of H 2 O 2 , O 3 and nitrogen oxides (NO x ) in treated water decreased with increasing water content, and all the ones enhanced after discharge. The experimental results were further analyzed by chemical reaction equations and commented by physical principles as much as possible. At last, the water containing phenol was tested in this system for the concentration from 100 mg/L to 9.8 mg/L in a period of 35 min. (paper)

  5. Protein kinase A governs oxidative phosphorylation kinetics and oxidant emitting potential at complex I

    Directory of Open Access Journals (Sweden)

    Daniel Stephen Lark

    2015-11-01

    Full Text Available The mitochondrial electron transport system (ETS is responsible for setting and maintaining both the energy and redox charges throughout the cell. Reversible phosphorylation of mitochondrial proteins, particularly via the soluble adenylyl cyclase (sAC/cyclic AMP (cAMP/Protein kinase A (PKA axis, has recently been revealed as a potential mechanism regulating the ETS. However, the governance of cAMP/PKA signaling and its implications on ETS function are incompletely understood. In contrast to prior reports using exogenous bicarbonate, we provide evidence that endogenous CO2 produced by increased tricarboxylic acid (TCA cycle flux is insufficient to increase mitochondrial cAMP levels, and that exogenous addition of membrane permeant 8Br-cAMP does not enhance mitochondrial respiratory capacity. We also report important non-specific effects of commonly used inhibitors of sAC which preclude their use in studies of mitochondrial function. In isolated liver mitochondria, inhibition of PKA reduces complex I-, but not complex II-supported respiratory capacity. In permeabilized myofibers, inhibition of PKA lowers both the Km and Vmax for complex I-supported respiration as well as succinate-supported H2O2 emitting potential. In summary, the data provided here improve our understanding of how mitochondrial cAMP production is regulated, illustrate a need for better tools to examine the impact of sAC activity on mitochondrial biology, and suggest that cAMP/PKA signaling contributes to the governance of electron flow through complex I of the ETS.

  6. Oxygen potential of a prototypic Mo-cermet fuel containing plutonium oxide

    Energy Technology Data Exchange (ETDEWEB)

    Miwa, Shuhei, E-mail: miwa.shuhei@jaea.go.jp [Japan Atomic Energy Agency, 4002 Narita-cho, Oarai-machi, Higashiibaraki-gun, Ibaraki, 311-1393 (Japan); Osaka, Masahiko [Japan Atomic Energy Agency, 4002 Narita-cho, Oarai-machi, Higashiibaraki-gun, Ibaraki, 311-1393 (Japan); Nozaki, Takahiro; Arima, Tatsumi; Idemitsu, Kazuya [Kyushu University, 744 Motooka Nishi-ku, Fukuoka, 819-0395 (Japan)

    2015-10-15

    Oxygen potential of a prototypic Mo-cermet fuel containing 50 vol.% PuO{sub 2−x} were investigated by the thermogravimetric analysis in the temperature range from 1273 K to 1473 K. It was shown that the oxygen potential and oxidation rate of the Mo-cermet were the same as those of pure PuO{sub 2−x} below the oxygen potential of Mo/MoO{sub 2} oxidation reaction. The same features of the Mo-cermet sample containing 50 vol.% PuO{sub 2−x} with those of pure PuO{sub 2−x} were discussed in terms of the microstructure. - Highlights: • Oxygen potential of Mo-cermet fuel was investigated by thermogravimetric analysis. • It was the same as that of pure PuO{sub 2−x} below the oxygen potential for Mo/MoO{sub 2}. • Gradual oxidation of Mo matrix occurred only above the oxygen potential for Mo/MoO{sub 2}. • Mo matrix and PuO{sub 2−x} in Mo-cermet fuel can thus be thermochemically individual.

  7. Oxygen potential of a prototypic Mo-cermet fuel containing plutonium oxide

    International Nuclear Information System (INIS)

    Miwa, Shuhei; Osaka, Masahiko; Nozaki, Takahiro; Arima, Tatsumi; Idemitsu, Kazuya

    2015-01-01

    Oxygen potential of a prototypic Mo-cermet fuel containing 50 vol.% PuO_2_−_x were investigated by the thermogravimetric analysis in the temperature range from 1273 K to 1473 K. It was shown that the oxygen potential and oxidation rate of the Mo-cermet were the same as those of pure PuO_2_−_x below the oxygen potential of Mo/MoO_2 oxidation reaction. The same features of the Mo-cermet sample containing 50 vol.% PuO_2_−_x with those of pure PuO_2_−_x were discussed in terms of the microstructure. - Highlights: • Oxygen potential of Mo-cermet fuel was investigated by thermogravimetric analysis. • It was the same as that of pure PuO_2_−_x below the oxygen potential for Mo/MoO_2. • Gradual oxidation of Mo matrix occurred only above the oxygen potential for Mo/MoO_2. • Mo matrix and PuO_2_−_x in Mo-cermet fuel can thus be thermochemically individual.

  8. Combining Urease and Nitrification Inhibitors with Incorporation Reduces Ammonia and Nitrous Oxide Emissions and Increases Corn Yields.

    Science.gov (United States)

    Drury, Craig F; Yang, Xueming; Reynolds, W Dan; Calder, Wayne; Oloya, Tom O; Woodley, Alex L

    2017-09-01

    Less than 50% of applied nitrogen (N) fertilizer is typically recovered by corn ( L.) due to climatic constraints, soil degradation, overapplication, and losses to air and water. Two application methods, two N sources, and two inhibitors were evaluated to reduce N losses and enhance crop uptake. The treatments included broadcast urea (BrUrea), BrUrea with a urease inhibitor (BrUrea+UI), BrUrea with a urease and a nitrification inhibitor (BrUrea+UI+NI), injection of urea ammonium nitrate (InjUAN), and injected with one or both inhibitors (InjUAN+UI, InjUAN+UI+NI), and a control. The BrUrea treatment lost 50% (64.4 kg N ha) of the applied N due to ammonia volatilization, but losses were reduced by 64% with BrUrea+UI+NI (23.0 kg N ha) and by 60% with InjUAN (26.1 kg N ha). Ammonia losses were lower and crop yields were greater in 2014 than 2013 as a result of the more favorable weather when N was applied in 2014. When ammonia volatilization was reduced by adding a urease inhibitor, NO emissions were increased by 30 to 31% with BrUrea+UI and InjUAN+UI compared with BrUrea and InjUAN, respectively. Pollution swapping was avoided when both inhibitors were used (BrUrea+UI+NI, InjUAN+UI+NI) as both ammonia volatilization and NO emissions were reduced, and corn grain yields increased by 5% with BrUrea+UI+NI and by 7% with InjUAN+UI+NI compared with BrUrea and InjUAN, respectively. The combination of two N management strategies (InjUAN+UI+NI) increased yields by 19% (12.9 t ha) compared with BrUrea (10.8 t ha). Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  9. Oxygen transport by oxygen potential gradient in dense ceramic oxide membranes

    Energy Technology Data Exchange (ETDEWEB)

    Maiya, P.S.; Balachandran, U.; Dusek, J.T.; Mieville, R.L. [Argonne National Lab., IL (United States). Energy Technology Div.; Kleefisch, M.S.; Udovich, C.A. [Amoco Exploration/Production, Naperville, IL (United States)

    1996-05-01

    Numerous studies have been conducted in recent years on the partial oxidation of methane to synthesis gas (syngas: CO + H{sub 2}) with air as the oxidant. In partial oxidation, a mixed-oxide ceramic membrane selectively transports oxygen from the air; this transport is driven by the oxygen potential gradient. Of the several ceramic materials the authors have tested, a mixed oxide based on the Sr-Fe-Co-O system has been found to be very attractive. Extensive oxygen permeability data have been obtained for this material in methane conversion experiments carried out in a reactor. The data have been analyzed by a transport equation based on the phenomenological theory of diffusion under oxygen potential gradients. Thermodynamic calculations were used to estimate the driving force for the transport of oxygen ions. The results show that the transport equation deduced from the literature describes the permeability data reasonably well and can be used to determine the diffusion coefficients and the associated activation energy of oxygen ions in the ceramic membrane material.

  10. Comparison of the effects of semi-refined rice oil and soybean oil on meat oxidative stability, carcass yield, metabolism, and performance of broilers

    Directory of Open Access Journals (Sweden)

    ML de Moraes

    2009-09-01

    Full Text Available Two experiments (EXP 1 and EXP 2 were conducted to compare soybean oil (SO and semi-refined rice oil (RBO added to broilers diets. In EXP 1, 400 male Ross x Ross 308 broilers were reared in battery cages, and their performance was evaluated. A metabolism assay was performed. In EXP 2, 1344 broilers from the same strain were reared in floor pens with rice husks litter. In addition to performance, carcass yield and meat oxidative stability were evaluated. In both EXP, birds were distributed in a 2x4 factorial arrangement, with two types of oils (SO or RBO and four oil inclusion levels (1%, 2.5%, 4%, or 5.5%. Two periods were considered: starter (1 to 21 days of age and grower (22 to 42 days. In both EXP, oil type had no influence on starter performance. Although treatments promoted similar in weight gain (WG and feed intake (FI, grower birds fed RBO had better feed conversion (FCR in EXP 2, but not in EXP1. In both trials, increasing dietary oil levels negatively influenced FI and positively FCR. Weight gain was similar among all treatments in EXP 1, whereas in EXP 2, WG was higher when 4 and 5.5% oil was included in the feed. RBO presented 94% fat metabolizability, and crude energy and metabolizable energy levels of 9.260 and 8.714 kcal/kg, respectively. Carcass yield was not influenced by oil type; however, oil inclusion level negatively affected breast yield. The experimental treatments had no effect on meat oxidative stability. RBO can be used as an alternative to soybean oil in broilers diets.

  11. Increased levels of thioredoxin in patients with abdominal aortic aneurysms (AAAs). A potential link of oxidative stress with AAA evolution

    DEFF Research Database (Denmark)

    Martinez-Pinna, R; Lindholt, Jes S.; Blanco-Colio, L M

    2010-01-01

    Oxidative stress is a main mechanism involved in vascular pathologies. Increased thioredoxin (TRX) levels have been observed in several oxidative stress-associated cardiovascular diseases. We aim to test the potential role of TRX as a biomarker of oxidative stress in abdominal aortic aneurysm (AAA)....

  12. General regularity of the oxidation potential variations and high oxidation states in the second half of the actinide series

    International Nuclear Information System (INIS)

    Spitsyn, V.I.; Vokhmin, V.G.; Ionova, G.V.; Pershina, V.G.

    1984-01-01

    Oxidation potentials (OP) PHI(4/3), PHI(5/3), PHI(6/3), PHI(5/4) and PHI(6/5) are calculated for the members of the actinide series. A semiemperic relation combining OP with explicit terms for ground level energies of actinide ions in Russell-Saunders approximation as well as known values of formal OP relative to the normal hydrogen electrode potential are used as an extrapolation function. It is shown that an increase of PHI(4/3) OP which occurs after Bsub(k) explains a low stability of the oxidation state 4 in solutions for actinides of the second half of the series. PHI(5/3) and PHI(5/4) OP in the section starting with Cm have the minimum at Cf. PHI(6/3) OP for Cm, Bk, Cf and Es are practically the same but for Cm, Bk and Es they are smaller than PHI(5/3) OP. A principle possibility of Bk(6), Cf(6) and Es(6) preparation is shown

  13. QSARs for phenols and phenolates: oxidation potential as a predictor of reaction rate constants with photochemically produced oxidants.

    Science.gov (United States)

    Arnold, William A; Oueis, Yan; O'Connor, Meghan; Rinaman, Johanna E; Taggart, Miranda G; McCarthy, Rachel E; Foster, Kimberley A; Latch, Douglas E

    2017-03-22

    Quantitative structure-activity relationships (QSARs) for prediction of the reaction rate constants of phenols and phenolates with three photochemically produced oxidants, singlet oxygen, carbonate radical, and triplet excited state sensitizers/organic matter, are developed. The predictive variable is the one-electron oxidation potential (E 1 ), which is calculated for each species using density functional theory. The reaction rate constants are obtained from the literature, and for singlet oxygen, are augmented with new experimental data. Calculated E 1 values have a mean unsigned error compared to literature values of 0.04-0.06 V. For singlet oxygen, a single linear QSAR that includes both phenols and phenolates is developed that predicts experimental rate constants, on average, to within a factor of three. Predictions for only 6 out of 87 compounds are off by more than a factor of 10. A more limited data set for carbonate radical reactions with phenols and phenolates also gives a single linear QSAR with prediction of rate constant being accurate to within a factor of three. The data for the reactions of phenols with triplet state sensitizers demonstrate that two sensitizers, 2-acetonaphthone and methylene blue, most closely predict the reactivity trend of triplet excited state organic matter with phenols. Using sensitizers with stronger reduction potentials could lead to overestimation of rate constants and thus underestimation of phenolic pollutant persistence.

  14. Biological durability and oxidative potential of a stonewool mineral fibre compared to crocidolite asbestos fibres

    Energy Technology Data Exchange (ETDEWEB)

    Hippeli, S. [Lehrstuhl fuer Phytopathologie, Labor fuer Biochemische Toxikologie, Technische Universitaet Muenchen-Weihenstephan, D-85350 Freising-Weihenstephan (Germany); Dornisch, K. [Lehrstuhl fuer Phytopathologie, Labor fuer Biochemische Toxikologie, Technische Universitaet Muenchen-Weihenstephan, D-85350 Freising-Weihenstephan (Germany); Kaiser, S. [Lehrstuhl fuer Phytopathologie, Labor fuer Biochemische Toxikologie, Technische Universitaet Muenchen-Weihenstephan, D-85350 Freising-Weihenstephan (Germany); Draeger, U. [Deutsche Rockwool Mineralwoll GmbH, Karl-Schneider-Strasse 14-18, D-45966 Gladbeck (Germany); Elstner, E.F. [Lehrstuhl fuer Phytopathologie, Labor fuer Biochemische Toxikologie, Technische Universitaet Muenchen-Weihenstephan, D-85350 Freising-Weihenstephan (Germany)

    1997-07-01

    Experiments are described concerning the differences in redox properties and biodurability of natural asbestos fibres and an experimental stonewool fibre incubated in Gamble solution and reconstructed surfactant fluid. Crocidolite exhibits a significantly higher oxidative potential compared to the tested stonewool fibres. The oxidative acitivity of both types of fibres is not constant during incubation over several weeks, but rather shows a sinoidal curve including reactivities much higher than those at the beginning of the incubation. A continuous loss of mass is concluded not to be definitively connected with a continuous loss of toxicity. (orig.). With 1 fig.

  15. Nitrous oxide production and consumption potential in an agricultural and a forest soil

    DEFF Research Database (Denmark)

    Yu, Kewei; Struwe, Sten; Kjøller, Annelise

    2008-01-01

    Both a laboratory incubation experiment using soils from an agricultural field and a forest and field measurements at the same locations were conducted to determine nitrous oxide (N2O) production and consumption (reduction) potentials using the acetylene (C2H2) inhibition technique. Results from...... measurements show that average N2O emission rates were 0.56 and 0.59 kg N ha-1 in the agricultural field and forest, respectively. When C2H2 was provided in the field measurements, N2O emission rates from the agricultural field and forest increased by 38 and 51%, respectively. Nitrous oxide consumption under...

  16. Bending localization of nitrous oxide under anharmonicity and Fermi coupling: the dynamical potential approach

    International Nuclear Information System (INIS)

    Zhang Chi; Wu Guo-Zhen; Fang Chao

    2010-01-01

    This paper studies the vibrational nonlinear dynamics of nitrous oxide with Fermi coupling between the symmetric stretching and bending coordinates by classical dynamical potential approach. This is a global approach in the sense that the overall dynamics is evidenced by the classical nonlinear variables such as the fixed points and the focus are on a set of levels instead of individual ones. The dynamics of nitrous oxide is demonstrated to be not so much dependent on the excitation energy. Moreover, the localized bending mode is shown to be ubiquitous in all the energy range studied

  17. A review of the breeding potentials of carbide, nitride and oxide fueled LMFBRs and GCFRs

    International Nuclear Information System (INIS)

    Handa, Muneo

    1977-11-01

    The effects of design parameters in large variation on compound system doubling time of large advanced-fueled LMFBR are described on the base of recent U.S. results. The fuel element design by Combustion Engineering Inc. in step-by-step substitution of the initial oxide fuel subassemblies with carbide ones is explained. Breeding characteristics of the oxide-fueled LMFBR and its potential design modifications are expounded. The gas cooled fast breeder program in West Germany and in the United States are briefed. Definitions of the breeding ratio and doubling time in overall fuel cycle are given. (auth.)

  18. Set potential regulation reveals additional oxidation peaks of Geobacter sulfurreducens anodic biofilms

    KAUST Repository

    Zhu, Xiuping

    2012-08-01

    Higher current densities produced in microbial fuel cells and other bioelectrochemical systems are associated with the presence of various Geobacter species. A number of electron transfer components are involved in extracellular electron transfer by the model exoelectrogen, Geobacter sulfurreducens. It has previously been shown that 5 main oxidation peaks can be identified in cyclic voltammetry scans. It is shown here that 7 separate oxidation peaks emerged over relatively long periods of time when a larger range of set potentials was used to acclimate electroactive biofilms. The potentials of oxidation peaks obtained with G. sulfurreducens biofilms acclimated at 0.60 V (vs. Ag/AgCl) were different from those that developed at - 0.46 V, and both of their peaks were different from those obtained for biofilms incubated at - 0.30 V, 0 V, and 0.30 V. These results expand the known range of potentials for which G. sulfurreducens produces identifiable oxidation peaks that could be important for extracellular electron transfer. © 2012 Elsevier B.V.

  19. Potential role of green tea catechins in the management of oxidative stress-associated infertility.

    Science.gov (United States)

    Roychoudhury, Shubhadeep; Agarwal, Ashok; Virk, Gurpriya; Cho, Chak-Lam

    2017-05-01

    Reactive oxygen species (ROS) are present in low concentrations in the genital tracts of males and females. Excessive ROS lead to oxidative stress, which damages DNA, lipids and proteins. Such molecular changes result in compromised vitality, increased morphological defects and decreased sperm motility in the male. In the female, oxidative stress interferes with oocyte maturation, and may inhibit in-vitro maturation of the oocyte. Recently, green tea supplementation has been reported to possess properties that may improve the quality of male and female gametes largely due to the ability of catechin polyphenols to quench ROS. Epigallocatechin-3-gallate (EGCG) is considered the most promising bioactive compound in green tea due to its strong antioxidant activity. The unique property of green tea catechins may potentially improve reproductive health and pose an important research area. We present a comprehensive overview on the effects and potential roles of green tea catechins on oxidative stress in male and female reproduction and fertility. In this review, possible mechanisms of action are highlighted to better understand the potential use of green tea catechins in the reduction of oxidative stress and its associated beneficial effects in the clinical setting. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  20. Endophytes from medicinal plants and their potential for producing indole acetic acid, improving seed germination and mitigating oxidative stress* #

    Science.gov (United States)

    Khan, Abdul Latif; Gilani, Syed Abdullah; Waqas, Muhammad; Al-Hosni, Khadija; Al-Khiziri, Salima; Kim, Yoon-Ha; Ali, Liaqat; Kang, Sang-Mo; Asaf, Sajjad; Shahzad, Raheem; Hussain, Javid; Lee, In-Jung; Al-Harrasi, Ahmed

    2017-01-01

    Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants (Caralluma acutangula, Rhazya stricta, and Moringa peregrina) and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp. (6 isolates), Alternaria sp. (2), Bipolaris sp. (1), and Cladosporium sp. (1) based on 18S rDNA sequencing and phylogenetic analysis. The culture filtrates (CFs; 25%, 50%, and 100% concentrations) from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF (100%) of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry (GC/MS) analysis showed the highest indole acetic acid content ((54.31±0.21) µmol/L) in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses. PMID:28124841

  1. Endophytes from medicinal plants and their potential for producing indole acetic acid, improving seed germination and mitigating oxidative stress.

    Science.gov (United States)

    Khan, Abdul Latif; Gilani, Syed Abdullah; Waqas, Muhammad; Al-Hosni, Khadija; Al-Khiziri, Salima; Kim, Yoon-Ha; Ali, Liaqat; Kang, Sang-Mo; Asaf, Sajjad; Shahzad, Raheem; Hussain, Javid; Lee, In-Jung; Al-Harrasi, Ahmed

    Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants (Caralluma acutangula, Rhazya stricta, and Moringa peregrina) and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp. (6 isolates), Alternaria sp. (2), Bipolaris sp. (1), and Cladosporium sp. (1) based on 18S rDNA sequencing and phylogenetic analysis. The culture filtrates (CFs; 25%, 50%, and 100% concentrations) from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF (100%) of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry (GC/MS) analysis showed the highest indole acetic acid content ((54.31±0.21) µmol/L) in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses.

  2. Potencial produtivo de videiras cultivadas sob cobertura de plástico Yield potential of grapevine cultivated under plastic cover

    Directory of Open Access Journals (Sweden)

    Geraldo Chavarria

    2009-02-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência do uso de cobertura de plástico sobre os componentes do rendimento da videira (Vitis vinifera L. cultivar Moscato Giallo. O experimento foi realizado nas safras 2005/2006 e 2006/2007, em Flores da Cunha, RS, em duas áreas de vinhedo, uma com cobertura de plástico impermeável e outra sem cobertura (controle. O microclima foi avaliado quanto à temperatura e umidade relativa do ar, radiação fotossinteticamente ativa e velocidade do vento próximo ao dossel vegetativo e a os cachos. A avaliação dos componentes de rendimento ocorreu em delineamento experimental inteiramente ao acaso, e foram identificadas dez plantas marcadas aleatoriamente em cada área. Avaliaram-se a produção por planta e por hectare, o número de cachos por planta e por metro quadrado, o número de sarmentos por metro quadrado, a massa e comprimento de cacho, a massa de engaço, o número de bagas por cacho, o diâmetro transversal de bagas e a relação entre massa de película e massa de polpa. Acobertura de plástico possibilita aumento na produtividade, não afeta a relação entre massa de casca e massa de polpa das bagas e favorece a estabilidade de produção, independentemente das condições meteorológicas no ciclo.The objective of this work was to evaluate the effect of plastic cover on the yield components of grapevine (Vitis vinifera L. cultivar Moscato Giallo. The experiment was carried out in 2005/2006 and 2006/2007 crop seasons, in Flores da Cunha, RS, Brazil, in two vineyard areas, one covered with an impermeable plastic film and other without covering (control. The microclimate was evaluated in terms of air temperature, air relative humidity, photosynthetically active radiation and wind speed above canopy and close to clusters. The yield components were evaluated in a completely randomized design, in ten plants randomly selected in each area. Measures were made for production per plant, yield per

  3. Preparation and characterization of an iron oxide-hydroxyapatite nanocomposite for potential bone cancer therapy.

    Science.gov (United States)

    Sneha, Murugesan; Sundaram, Nachiappan Meenakshi

    2015-01-01

    Recently, multifunctional magnetic nanostructures have been found to have potential applications in biomedical and tissue engineering. Iron oxide nanoparticles are biocompatible and have distinctive magnetic properties that allow their use in vivo for drug delivery and hyperthermia, and as T2 contrast agents for magnetic resonance imaging. Hydroxyapatite is used frequently due to its well-known biocompatibility, bioactivity, and lack of toxicity, so a combination of iron oxide and hydroxyapatite materials could be useful because hydroxyapatite has better bone-bonding ability. In this study, we prepared nanocomposites of iron oxide and hydroxyapatite and analyzed their physicochemical properties. The results suggest that these composites have superparamagnetic as well as biocompatible properties. This type of material architecture would be well suited for bone cancer therapy and other biomedical applications.

  4. Effects of oxidation potential and retention time on electrochromic stability of poly (3-hexyl thiophene) films

    Science.gov (United States)

    Kim, Tae-Ho; Hyun Song, Seok; Kim, Hyo-Jae; Oh, Seong-Hyeon; Han, Song-Yi; Kim, Goung; Nah, Yoon-Chae

    2018-06-01

    Herein, we report the effects of applied voltage on the electrochromic (EC) stability of poly(3-hexylthiophene) (P3HT) films during EC reactions. The transmittance difference and cycling stability of these films were monitored to optimize the oxidation voltage, and their chemical compositions were analyzed by X-ray photoelectron spectroscopy after long-term electrochemical cycling. High oxidation voltages increased the color contrast of P3HT films but decreased their cycling stability due to facilitating chemical degradation. Furthermore, at an optimized oxidation voltage, the retention time during potential pulsing was adjusted utilizing the optical memory of P3HT, revealing that the decreased voltage application time reduced power consumption by 9.6% and enhanced EC stability without loss of color contrast.

  5. Boosting biomethane yield and production rate with graphene: The potential of direct interspecies electron transfer in anaerobic digestion.

    Science.gov (United States)

    Lin, Richen; Cheng, Jun; Zhang, Jiabei; Zhou, Junhu; Cen, Kefa; Murphy, Jerry D

    2017-09-01

    Interspecies electron transfer between bacteria and archaea plays a vital role in enhancing energy efficiency of anaerobic digestion (AD). Conductive carbon materials (i.e. graphene nanomaterial and activated charcoal) were assessed to enhance AD of ethanol (a key intermediate product after acidogenesis of algae). The addition of graphene (1.0g/L) resulted in the highest biomethane yield (695.0±9.1mL/g) and production rate (95.7±7.6mL/g/d), corresponding to an enhancement of 25.0% in biomethane yield and 19.5% in production rate. The ethanol degradation constant was accordingly improved by 29.1% in the presence of graphene. Microbial analyses revealed that electrogenic bacteria of Geobacter and Pseudomonas along with archaea Methanobacterium and Methanospirillum might participate in direct interspecies electron transfer (DIET). Theoretical calculations provided evidence that graphene-based DIET can sustained a much higher electron transfer flux than conventional hydrogen transfer. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Exercise and oxidative stress: potential effects of antioxidant dietary strategies in sports.

    Science.gov (United States)

    Pingitore, Alessandro; Lima, Giuseppina Pace Pereira; Mastorci, Francesca; Quinones, Alfredo; Iervasi, Giorgio; Vassalle, Cristina

    2015-01-01

    Free radicals are produced during aerobic cellular metabolism and have key roles as regulatory mediators in signaling processes. Oxidative stress reflects an imbalance between production of reactive oxygen species and an adequate antioxidant defense. This adverse condition may lead to cellular and tissue damage of components, and is involved in different physiopathological states, including aging, exercise, inflammatory, cardiovascular and neurodegenerative diseases, and cancer. In particular, the relationship between exercise and oxidative stress is extremely complex, depending on the mode, intensity, and duration of exercise. Regular moderate training appears beneficial for oxidative stress and health. Conversely, acute exercise leads to increased oxidative stress, although this same stimulus is necessary to allow an up-regulation in endogenous antioxidant defenses (hormesis). Supporting endogenous defenses with additional oral antioxidant supplementation may represent a suitable noninvasive tool for preventing or reducing oxidative stress during training. However, excess of exogenous antioxidants may have detrimental effects on health and performance. Whole foods, rather than capsules, contain antioxidants in natural ratios and proportions, which may act in synergy to optimize the antioxidant effect. Thus, an adequate intake of vitamins and minerals through a varied and balanced diet remains the best approach to maintain an optimal antioxidant status. Antioxidant supplementation may be warranted in particular conditions, when athletes are exposed to high oxidative stress or fail to meet dietary antioxidant requirements. Aim of this review is to discuss the evidence on the relationship between exercise and oxidative stress, and the potential effects of dietary strategies in athletes. The differences between diet and exogenous supplementation as well as available tools to estimate effectiveness of antioxidant intake are also reported. Finally, we advocate the need

  7. Calibration of redox potential in sperm wash media and evaluation of oxidation-reduction potential values in various assisted reproductive technology culture media using MiOXSYS system.

    Science.gov (United States)

    Panner Selvam, M K; Henkel, R; Sharma, R; Agarwal, A

    2018-03-01

    Oxidation-reduction potential describes the balance between the oxidants and antioxidants in fluids including semen. Various artificial culture media are used in andrology and IVF laboratories for sperm preparation and to support the development of fertilized oocytes under in vitro conditions. The composition and conditions of these media are vital for optimal functioning of the gametes. Currently, there are no data on the status of redox potential of sperm processing and assisted reproduction media. The purpose of this study was to compare the oxidation-reduction potential values of the different media and to calibrate the oxidation-reduction potential values of the sperm wash medium using oxidative stress inducer cumene hydroperoxide and antioxidant ascorbic acid. Redox potential was measured in 10 different media ranging from sperm wash media, freezing media and assisted reproductive technology one-step medium to sequential media. Oxidation-reduction potential values of the sequential culture medium and one-step culture medium were lower and significantly different (p value to identify the physiological range of oxidation-reduction potential that does not have any adverse effect on normal physiological sperm function. © 2017 American Society of Andrology and European Academy of Andrology.

  8. A twisted tale - how biocorrosion communities yield new insight on the distribution of marine iron-oxidizing bacteria

    Science.gov (United States)

    McBeth, J. M.; Emerson, D.

    2011-12-01

    Microbiologically influenced corrosion (MIC) of mild steel is a complex process involving biogeochemical interactions between bacteria, steel surfaces, and biogenic and abiotically produced minerals. The role of neutrophilic iron-oxidizing bacteria (FeOB) in this process is poorly understood, and surprisingly, little is known about the microbial ecology of corroding steel in marine environments. Based on previous work (McBeth et al 2011), we hypothesized that coastal sediments act as reservoirs for marine FeOB of the candidatus class 'Zetaproteobacteria', and that these bacteria will colonize and become numerically abundant on steel surfaces. To test this, mild steel coupons were incubated in a salt marsh and sampled over 40 days in summer 2010. DNA extracted from the steel surfaces was analyzed for overall bacterial diversity by pyrosequencing of the V4 variable region of the 16S rRNA gene, and relevant communities were quantified using qPCR. The qPCR analyses were done using 16S primers specific to prokaryotes (Takai & Horikoshi 2000) and Zetaproteobacteria (Kato et al 2009), and a dsrA gene specific primer (Ben-Dov et al 2007) to assess the population of sulfate-reducing bacteria (SRB). Pyrosequencing data analyses showed Zetaproteobacteria were present on steel samples throughout the incubations and were also present in adjacent sediments; however, the diversity of Zetaproteobacteria was lower on the steel in comparison with sediments, indicating specific populations were enriched on the steel coupons. Iron oxyhydroxide stalk biosignatures were observed on the steel and in enrichment cultures, evidence that the Zetaproteobacteria identified using molecular techniques were likely FeOB. Relatives of the H2-oxidizing genus Hydrogenophaga and members of the family Rhodobacterales were also identified as important members of the biocorrosion community and were present both on steel and in sediments. The diversity of these organisms on steel surfaces increased with

  9. Growth, reproductive phenology and yield responses of a potential biofuel plant, Jatropha curcas grown under projected 2050 levels of elevated CO2.

    Science.gov (United States)

    Kumar, Sumit; Chaitanya, Bharatula S K; Ghatty, Sreenivas; Reddy, Attipalli R

    2014-11-01

    Jatropha (Jatropha curcas) is a non-edible oil producing plant which is being advocated as an alternative biofuel energy resource. Its ability to grow in diverse soil conditions and minimal requirements of essential agronomical inputs compared with other oilseed crops makes it viable for cost-effective advanced biofuel production. We designed a study to investigate the effects of elevated carbon dioxide concentration ([CO(2)]) (550 ppm) on the growth, reproductive development, source-sink relationships, fruit and seed yield of J. curcas. We report, for the first time that elevated CO(2) significantly influences reproductive characteristics of Jatropha and improve its fruit and seed yields. Net photosynthetic rate of Jatropha was 50% higher in plants grown in elevated CO(2) compared with field and ambient CO(2) -grown plants. The study also revealed that elevated CO(2) atmosphere significantly increased female to male flower ratio, above ground biomass and carbon sequestration potential in Jatropha (24 kg carbon per tree) after 1 year. Our data demonstrate that J. curcas was able to sustain enhanced rate of photosynthesis in elevated CO(2) conditions as it had sufficient sink strength to balance the increased biomass yields. Our study also elucidates that the economically important traits including fruit and seed yield in elevated CO(2) conditions were significantly high in J. curcas that holds great promise as a potential biofuel tree species for the future high CO(2) world. © 2014 Scandinavian Plant Physiology Society.

  10. Yield potential and fruit quality of scallop squash (Cucurbita pepo L. var. patissonina Greb. f. radiata Nois. cultivars grown for processing

    Directory of Open Access Journals (Sweden)

    Eugeniusz Kołota

    2015-10-01

    Full Text Available Scallop squash fruits may be harvested at different stages of development. Small size fruits, intended both for the fresh market and the food industry, have the highest biological value. This study was conducted to determine the yield potential of scallop squash cultivars (‘Polo F1’, ‘Disco’, ‘Gagat’, ‘Okra’, ‘Sunny Delight F1’ grown on mulched (black polyethylene foil or black agrotextile or unmulched soil, and harvested when fruits reached a diameter of 3–6 cm. Based on 3-year average data, the highest marketable and early yield was produced by ‘Sunny Delight F1’. This cultivar is also appreciated by consumers for its yellow colored skin of fruits. Another advantage of this cultivar was its high nutritional value expressed by the highest content of dry matter, vitamin C, polyphenols and minerals (K, P, Ca, Mg, with limited tendency to nitrate accumulation. Among the other cultivars tested, ‘Okra’ showed high yield potential, ‘Gagat’ was a rich source of carotenoids, and ‘Disco’ – polyphenols. Black polyethylene foil and black agrotextile appeared to be equally effective mulching materials. The benefit from the application of mulch was a significant increase in yield without any change in the chemical composition of the fruit.

  11. CERES-Maize model-based simulation of climate change impacts on maize yields and potential adaptive measures in Heilongjiang Province, China.

    Science.gov (United States)

    Lin, Yumei; Wu, Wenxiang; Ge, Quansheng

    2015-11-01

    Climate change would cause negative impacts on future agricultural production and food security. Adaptive measures should be taken to mitigate the adverse effects. The objectives of this study were to simulate the potential effects of climate change on maize yields in Heilongjiang Province and to evaluate two selected typical household-level autonomous adaptive measures (cultivar changes and planting time adjustments) for mitigating the risks of climate change based on the CERES-Maize model. The results showed that flowering duration and maturity duration of maize would be shortened in the future climate and thus maize yield would reduce by 11-46% during 2011-2099 relative to 1981-2010. Increased CO2 concentration would not benefit maize production significantly. However, substituting local cultivars with later-maturing ones and delaying the planting date could increase yields as the climate changes. The results provide insight regarding the likely impacts of climate change on maize yields and the efficacy of selected adaptive measures by presenting evidence-based implications and mitigation strategies for the potential negative impacts of future climate change. © 2014 Society of Chemical Industry.

  12. Métodos para a estimativa do potencial de rendimento da soja durante a ontogenia Methods for estimating the soybean potential yield during ontogeny

    Directory of Open Access Journals (Sweden)

    João Leonardo Fernandes Pires

    2005-04-01

    Full Text Available O objetivo deste trabalho foi estudar métodos para a estimativa do potencial de rendimento da soja durante a ontogenia. Os experimentos foram realizados em Eldorado do Sul, RS, durante as safras de 1996/1997, 1999/2000 e 2000/2001. Os tratamentos constaram de cinco cultivares de soja, FT-Saray, IAS 5, IAS 4, FT-Abyara e FEPAGRO RS-10. Cinco métodos foram utilizados para estimar o rendimento que seria obtido se todas as estruturas reprodutivas presentes no florescimento e no início do enchimento de grãos, produzissem grãos na maturação. O potencial de rendimento no florescimento e no enchimento de grãos, apresentou alta correlação com o número de flores e estruturas reprodutivas, respectivamente. Verificou-se, também, correspondência entre os métodos. Não houve, na maioria das vezes, correlações significativas entre o potencial, no florescimento e enchimento de grãos, e o rendimento de grãos na maturação. Os métodos estudados constituem ferramentas importantes para o manejo, quando utilizados para comparar o potencial de rendimento durante a ontogenia.The objective of this work was to study methods to estimate the soybean potential yield during ontogeny. The experiments were performed in Eldorado do Sul, RS, during the growing seasons of 1996/1997, 1999/2000 and 2000/2001. The treatments consisted of five soybean cultivars, FT-Saray, IAS 5, IAS 4, FT-Abyara and FEPAGRO RS-10. It was calculated the potential yield of each cultivar, by five methods, in order to estimate the yield that would be obtained if all the reproductive structures during flowering and beginning of pod filling produced grains at the maturity. Potential yield (during flowering and pod filling presented a high correlation with the number of flowers and reproductive structures, respectively. It was also found a correspondence among the methods. Most of the time, it did not occurred significant correlations between potential (during flowering and pod filling

  13. Iron and manganese in oxide minerals and in glasses: preliminary consideration of Eh buffering potential at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Caporuscio, F.A.; Vaniman, D.T.

    1985-04-01

    The tuffs of Yucca Mountain at the Nevada Test Site are currently under investigation as a possible deep burial site for high-level radioactive waste disposal. One of the main concerns is the effect of oxidizing groundwater on the transport of radionuclides. Rock components that may affect the oxygen content of groundwater include Fe-Ti oxides, Mn oxides, and glasses that contain ferrous iron. Some phenocryst Fe-Ti oxides at Yucca Mountain are in reduced states, whereas groundmass Fe-Ti oxides have been oxidized to hematite, rutile, and pseudobrookite (Fe 3+ -bearing phases) exclusively. Estimates of Fe 2+ -bearing oxides indicate that less than 0.33 vol% phenocrysts is available to act as solid buffering agents of Eh. Of this percentage, significant amounts of Fe-Ti oxides are isolated from effective interaction with groundwater because they occur in densely welded, devitrified tuffs that have low interstitial permeability. Manganese oxides occur primarily along fractures in the ash-flow tuffs. Because the Mn oxides are concentrated along the same pathways (fractures) where transport has occurred in the past, these small volume percentages could act as buffers. However, the oxidation states of actual Mn-oxide phases are high (Mn 4+ ), and these minerals have virtually no potential for reducing groundwater Eh. Manganese oxides may even act as oxidizing agents. However, regardless of their poor capabilities as reducing agents, the Mn oxides could be important as sorbents of heavy metals at Yucca Mountain. The lack of accessible, pristine Fe-Ti oxides and the generally high oxidation states of Mn oxides seem to rule out these oxides as Eh buffers of the Yucca Mountain groundwater system. Reduction of ferrous iron within glassy tuffs may have some effect on Eh, but further study is needed. At present it is prudent to assume that minerals and glasses have little or no capacity for reducing oxygen-rich groundwater at Yucca Mountain. 25 refs., 3 figs., 12 tabs

  14. Potential link between fruit yield, quality parameters and phytohormonal changes in preharvest UV-C treated strawberry.

    Science.gov (United States)

    Xu, Yanqun; Charles, Marie Thérèse; Luo, Zisheng; Roussel, Dominique; Rolland, Daniel

    2017-07-01

    Preharvest ultraviolet-C (UV-C) treatment of strawberry is a very new approach, and little information is available on the effect of this treatment on plant growth regulators. In this study, the effect of preharvest UV-C irradiations at three different doses on strawberry yield, fruit quality parameters and endogenous phytohormones was investigated simultaneously. The overall marketable yield of strawberry was not affected by the preharvest UV-C treatments, although more aborted and misshapen fruits were found in UV-C treated groups than in the untreated control. The fruits in the high dose group were firmer and had approximately 20% higher sucrose content and 15% higher ascorbic acid content than the control, while fruits from the middle and low dose groups showed no significant changes in these parameters. The lower abscisic acid (ABA) content found in the fruits in the high UV-C group may be associated with those quality changes. The citric acid content decreased only in the low dose group (reduction of 5.8%), with a concomitant 37% reduction in jasmonic acid (JA) content, compared to the control. The antioxidant status of fruits that received preharvest UV-C treatment was considered enhanced based on their oxygen radical absorbance capacity (ORAC) and malondialdehyde (MDA) content. In terms of aroma, three volatile alcohols differed significantly among the various treatments with obvious activation of alcohol acyltransferase (AAT) activity. The observed synchronous influence on physiological indexes and related phytohormones suggests that preharvest UV-C might affect fruit quality via the action of plant hormones. Crown Copyright © 2017. Published by Elsevier Masson SAS. All rights reserved.

  15. A low-temperature partial-oxidation-methanol micro reformer with high fuel conversion rate and hydrogen production yield

    International Nuclear Information System (INIS)

    Wang, Hsueh-Sheng; Huang, Kuo-Yang; Huang, Yuh-Jeen; Su, Yu-Chuan; Tseng, Fan-Gang

    2015-01-01

    Highlights: • A low-operating temperature of the POM-mode micro methanol reformer is obtained. • The effect of channel design on the performance is studied. • The effect of solid content and binder’ ratio on the performance is studied. • The centrifugal process is benefit for the modification of performance. • 98% of methanol conversion rate of the micro reformer can be obtained at 180 °C. - Abstract: A partial oxidation methanol micro reformer (POM-μReformer) with finger-shaped channels for low operating temperature and high conversing efficiency is proposed in this study. The micro reformer employs POM reaction for low temperature operation (less than 200 °C), exothermic reaction, and quick start-up, as well as air feeding capability; and the finger type reaction chambers for increasing catalyst loading as well as reaction area for performance enhancement. In this study, centrifugal technique was introduced to assist on the catalyst loading with high amount and uniform distribution. The solid content (S), binder’s ratio (B), and channel design (the ratio between channel’s length and width, R) were investigated in detail to optimize the design parameters. Scanning electron microscopy (SEM), gas chromatography (GC), and inductively coupled plasma-mass spectrometer (ICP-MS) were employed to analyze the performance of the POM-μReformer. The result depicted that the catalyst content and reactive area could be much improved at the optimized condition, and the conversion rate and hydrogen selectivity approached 97.9% and 97.4%, respectively, at a very low operating temperature of 180 °C with scarce or no binder in catalyst. The POM-μReformer can supply hydrogen to fuel cells by generating 2.23 J/min for 80% H 2 utilization and 60% fuel cell efficiency at 2 ml/min of supplied reactant gas, including methanol, oxygen and argon at a mixing ratio of 12.2%, 6.1% and 81.7%, respectively

  16. Decarboxylative alkylation for site-selective bioconjugation of native proteins via oxidation potentials.

    Science.gov (United States)

    Bloom, Steven; Liu, Chun; Kölmel, Dominik K; Qiao, Jennifer X; Zhang, Yong; Poss, Michael A; Ewing, William R; MacMillan, David W C

    2018-02-01

    The advent of antibody-drug conjugates as pharmaceuticals has fuelled a need for reliable methods of site-selective protein modification that furnish homogeneous adducts. Although bioorthogonal methods that use engineered amino acids often provide an elegant solution to the question of selective functionalization, achieving homogeneity using native amino acids remains a challenge. Here, we explore visible-light-mediated single-electron transfer as a mechanism towards enabling site- and chemoselective bioconjugation. Specifically, we demonstrate the use of photoredox catalysis as a platform to selectivity wherein the discrepancy in oxidation potentials between internal versus C-terminal carboxylates can be exploited towards obtaining C-terminal functionalization exclusively. This oxidation potential-gated technology is amenable to endogenous peptides and has been successfully demonstrated on the protein insulin. As a fundamentally new approach to bioconjugation this methodology provides a blueprint toward the development of photoredox catalysis as a generic platform to target other redox-active side chains for native conjugation.

  17. Standard test method for measurement of oxidation-reduction potential (ORP) of soil

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method covers a procedure and related test equipment for measuring oxidation-reduction potential (ORP) of soil samples removed from the ground. 1.2 The procedure in Section 9 is appropriate for field and laboratory measurements. 1.3 Accurate measurement of oxidation-reduction potential aids in the analysis of soil corrosivity and its impact on buried metallic structure corrosion rates. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  18. Decarboxylative alkylation for site-selective bioconjugation of native proteins via oxidation potentials

    Science.gov (United States)

    Bloom, Steven; Liu, Chun; Kölmel, Dominik K.; Qiao, Jennifer X.; Zhang, Yong; Poss, Michael A.; Ewing, William R.; MacMillan, David W. C.

    2018-02-01

    The advent of antibody-drug conjugates as pharmaceuticals has fuelled a need for reliable methods of site-selective protein modification that furnish homogeneous adducts. Although bioorthogonal methods that use engineered amino acids often provide an elegant solution to the question of selective functionalization, achieving homogeneity using native amino acids remains a challenge. Here, we explore visible-light-mediated single-electron transfer as a mechanism towards enabling site- and chemoselective bioconjugation. Specifically, we demonstrate the use of photoredox catalysis as a platform to selectivity wherein the discrepancy in oxidation potentials between internal versus C-terminal carboxylates can be exploited towards obtaining C-terminal functionalization exclusively. This oxidation potential-gated technology is amenable to endogenous peptides and has been successfully demonstrated on the protein insulin. As a fundamentally new approach to bioconjugation this methodology provides a blueprint toward the development of photoredox catalysis as a generic platform to target other redox-active side chains for native conjugation.

  19. Anti-atherosclerotic potential of gossypetin via inhibiting LDL oxidation and foam cell formation

    International Nuclear Information System (INIS)

    Chen, Jing-Hsien; Tsai, Chia-Wen; Wang, Chi-Ping; Lin, Hui-Hsuan

    2013-01-01

    Gossypetin, a flavone originally isolated from Hibiscus species, has been shown to possess antioxidant, antimicrobial, and antimutagenic activities. Here, we investigated the mechanism(s) underlying the anti-atherosclerotic potential of gossypetin. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) scavenging activity assay showed that the addition of > 50 μM of gossypetin could scavenge over 50% of DPPH radicals. The inhibitory effects of gossypetin on the lipid and protein oxidation of LDL were defined by thiobarbituric acid reactive substance (TBARS) assay, the relative electrophoretic mobility (REM) of oxidized LDL (ox-LDL), and fragmentation of apoB in the Cu 2+ -induced oxidation of LDL. Gossypetin showed potential in reducing ox-LDL-induced foam cell formation and intracellular lipid accumulation, and uptake ability of macrophages under non-cytotoxic concentrations. Molecular data showed that these influences of gossypetin might be mediated via peroxisome proliferator-activated receptor α (PPARα)/liver-X receptor α (LXRα)/ATP-binding cassette transporter A1 (ABCA1) and PPARγ/scavenger receptor CD36 pathways, as demonstrated by the transfection of PPARα siRNA or PPARγ expression vector. Our data implied that gossypetin regulated the PPAR signals, which in turn led to stimulation of cholesterol removal from macrophages and delay atherosclerosis. These results suggested that gossypetin potentially could be developed as an anti-atherosclerotic agent. - Highlights: • The anti-atherosclerotic effect of gossypetin in vitro was examined. • Gossypetin inhibited LDL oxidation. • Gossypetin showed potential in reducing on the formation of foam cells. • Gossypetin functions against ox-LDL through PPARa activation and PPARγ depression

  20. Anti-atherosclerotic potential of gossypetin via inhibiting LDL oxidation and foam cell formation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jing-Hsien [School of Nutrition, Chung Shan Medical University, Taichung, Taiwan (China); Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Tsai, Chia-Wen [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Wang, Chi-Ping [Department of Clinical Laboratory, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Lin, Hui-Hsuan, E-mail: linhh@csmu.edu.tw [Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan (China); School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China)

    2013-10-15

    Gossypetin, a flavone originally isolated from Hibiscus species, has been shown to possess antioxidant, antimicrobial, and antimutagenic activities. Here, we investigated the mechanism(s) underlying the anti-atherosclerotic potential of gossypetin. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) scavenging activity assay showed that the addition of > 50 μM of gossypetin could scavenge over 50% of DPPH radicals. The inhibitory effects of gossypetin on the lipid and protein oxidation of LDL were defined by thiobarbituric acid reactive substance (TBARS) assay, the relative electrophoretic mobility (REM) of oxidized LDL (ox-LDL), and fragmentation of apoB in the Cu{sup 2+}-induced oxidation of LDL. Gossypetin showed potential in reducing ox-LDL-induced foam cell formation and intracellular lipid accumulation, and uptake ability of macrophages under non-cytotoxic concentrations. Molecular data showed that these influences of gossypetin might be mediated via peroxisome proliferator-activated receptor α (PPARα)/liver-X receptor α (LXRα)/ATP-binding cassette transporter A1 (ABCA1) and PPARγ/scavenger receptor CD36 pathways, as demonstrated by the transfection of PPARα siRNA or PPARγ expression vector. Our data implied that gossypetin regulated the PPAR signals, which in turn led to stimulation of cholesterol removal from macrophages and delay atherosclerosis. These results suggested that gossypetin potentially could be developed as an anti-atherosclerotic agent. - Highlights: • The anti-atherosclerotic effect of gossypetin in vitro was examined. • Gossypetin inhibited LDL oxidation. • Gossypetin showed potential in reducing on the formation of foam cells. • Gossypetin functions against ox-LDL through PPARa activation and PPARγ depression.

  1. Changes in oxidative potential of soil and fly ash after reaction with gaseous nitric acid

    Science.gov (United States)

    Zhan, Ying; Ginder-Vogel, Matthew; Shafer, Martin M.; Rudich, Yinon; Pardo, Michal; Katra, Itzhak; Katoshevski, David; Schauer, James J.

    2018-01-01

    The goal of this study was to examine the impact of simulated atmospheric aging on the oxidative potential of inorganic aerosols comprised primarily of crustal materials. Four soil samples and one coal fly ash sample were artificially aged in the laboratory through exposure to the vapor from 15.8 M nitric acid solution for 24 h at room temperature. Native and acid-aged samples were analyzed with a cellular macrophage and acellular dithionthreitol assays to determine oxidative potential. Additionally, the samples were analyzed to determine the concentration of 50 elements, both total and the water-soluble fraction of these elements by Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICMS) and crystalline mineral composition using X-ray Diffraction (XRD). The results show that reactions with gaseous nitric acid increase the water-soluble fraction of many elements, including calcium, iron, magnesium, zinc, and lead. The mineral composition analysis documented that calcium-rich minerals present in the soils (e.g., calcite) are converted into different chemical forms, such as calcium nitrate (Ca(NO3)2). The nitric acid aging process, which can occur in the atmosphere, leads to a 200-600% increase in oxidative potential, as measured by cellular and acellular assays. This laboratory study demonstrates that the toxic effects of aged versus freshly emitted atmospheric dust may be quite different. In addition, the results suggest that mineralogical analysis of atmospheric dust may be useful in understanding its degree of aging.

  2. Study of the Higgs boson discovery potential in the process pp{yields}H/A{yields}{mu}{sup +}{mu}{sup -}/{tau}{sup +}{tau}{sup -} with the ATLAS detector

    Energy Technology Data Exchange (ETDEWEB)

    Dedes, Georgios

    2008-04-22

    In this thesis, the discovery potential of the ATLAS experiment at the Large Hadron Collider (LHC) at CERN for the heavy neutral Higgs bosons H/A of theMinimal Supersymmetric extension of the Standard Model of particle physics (MSSM) in the decay channels H/A{yields}{tau}{sup +}{tau}{sup -}{yields}e/{mu}+X and H/A{yields}{mu}{sup +}{mu}{sup -} has been studied. The ATLAS detector is designed to study the full spectrum of the physics phenomena occuring in the proton-proton collisions at 14 TeV center-of-mass energy and to provide answers to the question of the origin of particle masses and of electroweak symmetry breaking. For the studies, the ATLAS muon spectrometer plays an important role. The spectrometer allows for a precise muon momentum measurement independently of other ATLAS subdetectors. The performance of the muon spectrometer depends strongly on the performance of the muon tracking detectors, the Monitored Drift Tube Chambers (MDT). Computer programs have been developed in order to test and verify the ATLAS muon spectrometer simulation, an essential ingredient for data analysis. In addition, dedicated programs for the monitoring of the quality of the data collected by the muon spectrometer have been developed and tested with data from cosmic ray muons. High-quality cosmic ray muon data have been used for the calibration of the MDT-chambers. A new calibration method, called analytical autocalibration, has been tested. The proposed method achieved the required accuracy of 20 {mu}m in the determination of the space-to-drift-time relationship of the drift tubes of the MDT chambers with only 2000 muon tracks per chamber. Reliable muon detector simulation and calibration are essential for the study of the MSSM Higgs boson decays H/A{yields}{tau}{sup +}{tau}{sup -}{yields}e/{mu}+X and H/A{yields}{mu}{sup +}{mu}{sup -} and of the corresponding background processes. The signal selection and background rejection requirements have been optimized for maximum signal

  3. Improved Yield of High Molecular Weight DNA Coincides with Increased Microbial Diversity Access from Iron Oxide Cemented Sub-Surface Clay Environments

    Science.gov (United States)

    Hurt, Richard A.; Robeson, Michael S.; Shakya, Migun; Moberly, James G.; Vishnivetskaya, Tatiana A.; Gu, Baohua; Elias, Dwayne A.

    2014-01-01

    Despite over three decades of progress, extraction of high molecular weight (HMW) DNA from high clay soils or iron oxide cemented clay has remained challenging. HMW DNA is desirable for next generation sequencing as it yields the most comprehensive coverage. Several DNA extraction procedures were compared from samples that exhibit strong nucleic acid adsorption. pH manipulation or use of alternative ion solutions offered no improvement in nucleic acid recovery. Lysis by liquid N2 grinding in concentrated guanidine followed by concentrated sodium phosphate extraction supported HMW DNA recovery from clays high in iron oxides. DNA recovered using 1 M sodium phosphate buffer (PB) as a competitive desorptive wash was 15.22±2.33 µg DNA/g clay, with most DNA consisting of >20 Kb fragments, compared to 2.46±0.25 µg DNA/g clay with the Powerlyzer system (MoBio). Increasing PB concentration in the lysis reagent coincided with increasing DNA fragment length during initial extraction. Rarefaction plots of 16S rRNA (V1–V3 region) pyrosequencing from A-horizon and clay soils showed an ∼80% and ∼400% larger accessed diversity compared to the Powerlyzer soil DNA system, respectively. The observed diversity from the Firmicutes showed the strongest increase with >3-fold more operational taxonomic units (OTU) recovered. PMID:25033199

  4. Insights into organic carbon oxidation potential during fluvial transport from laboratory and field experiments

    Science.gov (United States)

    Scheingross, J. S.; Dellinger, M.; Eglinton, T. I.; Fuchs, M. C.; Golombek, N.; Hilton, R. G.; Hovius, N.; Lupker, M.; Repasch, M. N.; Sachse, D.; Turowski, J. M.; Vieth-Hillebrand, A.; Wittmann, H.

    2017-12-01

    Over geologic timescales, the exchange of organic carbon (OC) between the atmosphere, hydropshere, biosphere and geosphere can be a major control on atmospheric carbon dioxide concentrations. The carbon fluxes from the oxidation of rock-derived OC (a CO2 source) and erosion, transport, and burial of biospheric OC (a potential CO2 sink) during fluvial transit are approximately the same order of magnitude or larger than those from silicate weathering. Despite field data showing increasing oxidation of OC moving downstream in lowland rivers, it is unclear if losses occur primarily during active fluvial transport, where OC is in continual motion within an aerated river, or during periods of temporary storage in river floodplains which may be anoxic. The unknown location of OC oxidation (i.e., river vs. floodplain) limits our ability to mechanistically link geochemical and geomorphic processes which are required to develop models capable of predicting OC losses, constrain carbon budgets, and unravel links between climate, tectonics, and erosion. To fill this knowledge gap, we investigated OC oxidation in controlled laboratory experiments and a simplified field setting. We performed experiments in annular flumes that simulate fluvial transport without floodplain storage, allowing mixtures of OC-rich and siliciclastic sediment to be transported for distances of 1000 km. Preliminary experiments exploring both rock-derived and biospheric OC sources show minimal OC oxidation during active river transport, consistent with the idea that the majority of OC loss occurs during transient floodplain storage. These results are also consistent with new field data collected in the Rio Bermejo, Argentina, a lowland river traversing 800 km with no tributary inputs, where aged floodplain deposits have 3 to 10 times lower OC concentrations compared to modern river sediments. Together our field data and experiments support the hypothesis that oxidation of OC occurs primarily during

  5. Improving the oxidative stability of a high redox potential fungal peroxidase by rational design.

    Science.gov (United States)

    Sáez-Jiménez, Verónica; Acebes, Sandra; Guallar, Victor; Martínez, Angel T; Ruiz-Dueñas, Francisco J

    2015-01-01

    Ligninolytic peroxidases are enzymes of biotechnological interest due to their ability to oxidize high redox potential aromatic compounds, including the recalcitrant lignin polymer. However, different obstacles prevent their use in industrial and environmental applications, including low stability towards their natural oxidizing-substrate H2O2. In this work, versatile peroxidase was taken as a model ligninolytic peroxidase, its oxidative inactivation by H2O2 was studied and different strategies were evaluated with the aim of improving H2O2 stability. Oxidation of the methionine residues was produced during enzyme inactivation by H2O2 excess. Substitution of these residues, located near the heme cofactor and the catalytic tryptophan, rendered a variant with a 7.8-fold decreased oxidative inactivation rate. A second strategy consisted in mutating two residues (Thr45 and Ile103) near the catalytic distal histidine with the aim of modifying the reactivity of the enzyme with H2O2. The T45A/I103T variant showed a 2.9-fold slower reaction rate with H2O2 and 2.8-fold enhanced oxidative stability. Finally, both strategies were combined in the T45A/I103T/M152F/M262F/M265L variant, whose stability in the presence of H2O2 was improved 11.7-fold. This variant showed an increased half-life, over 30 min compared with 3.4 min of the native enzyme, under an excess of 2000 equivalents of H2O2. Interestingly, the stability improvement achieved was related with slower formation, subsequent stabilization and slower bleaching of the enzyme Compound III, a peroxidase intermediate that is not part of the catalytic cycle and leads to the inactivation of the enzyme.

  6. Improving the oxidative stability of a high redox potential fungal peroxidase by rational design.

    Directory of Open Access Journals (Sweden)

    Verónica Sáez-Jiménez

    Full Text Available Ligninolytic peroxidases are enzymes of biotechnological interest due to their ability to oxidize high redox potential aromatic compounds, including the recalcitrant lignin polymer. However, different obstacles prevent their use in industrial and environmental applications, including low stability towards their natural oxidizing-substrate H2O2. In this work, versatile peroxidase was taken as a model ligninolytic peroxidase, its oxidative inactivation by H2O2 was studied and different strategies were evaluated with the aim of improving H2O2 stability. Oxidation of the methionine residues was produced during enzyme inactivation by H2O2 excess. Substitution of these residues, located near the heme cofactor and the catalytic tryptophan, rendered a variant with a 7.8-fold decreased oxidative inactivation rate. A second strategy consisted in mutating two residues (Thr45 and Ile103 near the catalytic distal histidine with the aim of modifying the reactivity of the enzyme with H2O2. The T45A/I103T variant showed a 2.9-fold slower reaction rate with H2O2 and 2.8-fold enhanced oxidative stability. Finally, both strategies were combined in the T45A/I103T/M152F/M262F/M265L variant, whose stability in the presence of H2O2 was improved 11.7-fold. This variant showed an increased half-life, over 30 min compared with 3.4 min of the native enzyme, under an excess of 2000 equivalents of H2O2. Interestingly, the stability improvement achieved was related with slower formation, subsequent stabilization and slower bleaching of the enzyme Compound III, a peroxidase intermediate that is not part of the catalytic cycle and leads to the inactivation of the enzyme.

  7. Development of crossbreeding high-yield-potential strains for commercial cultivation in the medicinal mushroom Wolfiporia cocos (Higher Basidiomycetes).

    Science.gov (United States)

    Xiang, Xiaozhao; Wang, Xiaoxia; Bian, Yinbing; Xu, Zhangyi

    2016-07-01

    Wolfiporia cocos is a well-known medicinal mushroom, and its dried sclerotia has been widely used as a traditional medicine in China, Japan, and other Asian countries for centuries. However, long-term asexual reproduction of the breeding system in W. cocos results in a current universal degeneration of cultivated strains. To develop a W. cocos breeding program that will benefit commercial cultivation, we previously developed an optimum method for indoor induction of W. cocos fruiting bodies and clarified the nature of preponderant binuclear sexual basidiospores. In this paper, we first show that the majority of W. cocos single-spore isolates cannot form sclerotium in field cultivation. We then investigated the possibility of breeding new strains by crossbreeding. Three types of mating reactions were observed in both intra-strain pairings and inter-strain pairings, and a total of fifty-five hybrids were selected by antagonistic testing and allele-specific polymerase chain reaction (PCR). Field cultivation of hybrids demonstrated that some hybrids can form sclerotium via two cultivated methods. Two new high-yield strains were identified. This report will stimulate new thinking on W. cocos and promote further extensive studies on crossbreeding in W. cocos, a new topic related to the development of more efficient protocols for the discrimination of hybrids in W. cocos.

  8. Oxidative potential of gas phase combustion emissions - An underestimated and potentially harmful component of air pollution from combustion processes

    Science.gov (United States)

    Stevanovic, S.; Vaughan, A.; Hedayat, F.; Salimi, F.; Rahman, M. M.; Zare, A.; Brown, R. A.; Brown, R. J.; Wang, H.; Zhang, Z.; Wang, X.; Bottle, S. E.; Yang, I. A.; Ristovski, Z. D.

    2017-06-01

    The oxidative potential (OP) of the gas phase is an important and neglected aspect of environmental toxicity. Whilst prolonged exposure to particulate matter (PM) associated reactive oxygen species (ROS) have been shown to lead to negative health effects, the potential for compounds in gas phase to cause similar effects is yet to be understood. In this study we describe: the significance of the gas phase OP generated through vehicle emissions; discuss the origin and evolution of species contributing to measured OP; and report on the impact of gas phase OP on human lung cells. The model aerosol for this study was exhaust emitted from a Euro III Common-rail diesel engine fuelled with different blends of diesel and biodiesel. The gas phase of these emissions was found to be potentially as hazardous as the particle phase. Fuel oxygen content was found to negatively correlate with the gas phase OP, and positively correlate with particle phase OP. This signifies a complex interaction between reactive species present in gas and particle phase. Furthermore, this interaction has an overarching effect on the OP of both particle and gas phase, and therefore the toxicity of combustion emissions.

  9. Impact of Lygus spp. (Hemiptera: Miridae) on damage, yield and quality of lesquerella (Physaria fendleri), a potential new oil-seed crop.

    Science.gov (United States)

    Naranjo, Steven E; Ellsworth, Peter C; Dierig, David A

    2011-10-01

    Lesquerella, Physaria fendleri (A. Gray) S. Watson, is a mustard native to the western United States and is currently being developed as a commercial source of valuable hydroxy fatty acids that can be used in a number of industrial applications, including biolubricants, biofuel additives, motor oils, resins, waxes, nylons, plastics, corrosion inhibitors, cosmetics, and coatings. The plant is cultivated as a winter-spring annual and in the desert southwest it harbors large populations of arthropods, several of which could be significant pests once production expands. Lygus spp. (Hemiptera: Miridae) are common in lesquerella and are known pests of a number of agronomic and horticultural crops where they feed primarily on reproductive tissues. A 4-yr replicated plot study was undertaken to evaluate the probable impact of Lygus spp. on production of this potential new crop. Plant damage and subsequent seed yield and quality were examined relative to variable and representative densities of Lygus spp. (0.3-4.9 insects per sweep net) resulting from variable frequency and timing of insecticide applications. Increasing damage to various fruiting structures (flowers [0.9-13.9%], buds [1.2-7.1%], and seed pods [19.4-42.5%]) was significantly associated with increasing pest abundance, particularly the abundance of nymphs, in all years. This damage, however, did not consistently translate into reductions in seed yield (481-1,336 kg/ha), individual seed weight (0.5-0.7 g per 1,000 seed), or seed oil content (21.8-30.4%), and pest abundance generally explained relatively little of the variation in crop yield and quality. Negative effects on yield were not sensitive to the timing of pest damage (early versus late season) but were more pronounced during years when potential yields were lower due to weed competition and other agronomic factors. Results suggest that if the crop is established and managed in a more optimal fashion, Lygus spp. may not significantly limit yield

  10. [Intraoperative pain stimuli change somatosensory evoked potentials, but not auditory evoked potentials during isoflurane/nitrous oxide anesthesia].

    Science.gov (United States)

    Rundshagen, I; Kochs, E; Bischoff, P; Schulte am Esch, J

    1997-10-01

    Evoked potentials are used for intraoperative monitoring to assess changes of cerebral function. This prospective randomised study assesses the influence of surgical stimulation on midlatency components of somatosensory (SEPs) and auditory evoked potentials (AEPs) in anaesthetised patients. After approval of the Ethics Committee and written informed consent 36 orthopaedic patients (34 +/- 15 y, 73 +/- 14 kg. 1.71 +/- 0.07 m, ASA I-II) were randomly included in the study. Anaesthesia was induced with 1.5 micrograms/kg fentanyl, 0.3 mg/kg etomidate and 0.1 mg/kg vecuronium. The lungs were intubated and patients normoventilated in steady state anaesthesia with isoflurane (end-tidal 0.6%) and 66% nitrous oxide. 18 patients (group 1) were assigned to the SEP group: median nerve stimulation, recording at Erb, C 6 and the contralateral somatosensory cortex (N20, P25, N35) vs Fz. AEPs were recorded in group 2 (n = 18): binaural stimulation, recording at Cz versus linked mastoid (V, Na, Pa, Nb). Recordings were performed during 30 min before the start of surgery (baseline: BL), at skin incision (SURG1) and at the preparation of the periost (SURG2). Heart rate, mean arterial blood pressure, oxygen saturation, endtidal pCO2 and isoflurane (PetISO) concentrations were registered simultaneously. Data were analysed by one-way analysis of variance. Post hoc comparison were made by Mann-Whitney U-Wilcoxon Rank Sum Test with p beats/min) to SURG2 (76 +/- 12 beats/min). Increases of amplitudes of midlatency SEP amplitudes indicate increased nociceptive signal transmission which is not blunted by isoflurane-nitrous oxide anaesthesia. In contrast, unchanged AEPs indicate adequate levels of the hypnotic components of anaesthesia.

  11. Potentials and challenges of integration for complex metal oxides in CMOS devices and beyond

    International Nuclear Information System (INIS)

    Kim, Y; Pham, C; Chang, J P

    2015-01-01

    This review focuses on recent accomplishments on complex metal oxide based multifunctional materials and the potential they hold in advancing integrated circuits. It begins with metal oxide based high-κ materials to highlight the success of their integration since 45 nm complementary metal–oxide–semiconductor (CMOS) devices. By simultaneously offering a higher dielectric constant for improved capacitance as well as providing a thicker physical layer to prevent the quantum mechanical tunnelling of electrons, high-κ materials have enabled the continued down-scaling of CMOS based devices. The most recent technology driver has been the demand to lower device power consumption, which requires the design and synthesis of novel materials, such as complex metal oxides that exhibit remarkable tunability in their ferromagnetic, ferroelectric and multiferroic properties. These properties make them suitable for a wide variety of applications such as magnetoelectric random access memory, radio frequency band pass filters, antennae and magnetic sensors. Single-phase multiferroics, while rare, offer unique functionalities which have motivated much scientific and technological research to ascertain the origins of their multiferroicity and their applicability to potential devices. However, due to the weak magnetoelectric coupling for single-phase multiferroics, engineered multiferroic composites based on magnetostrictive ferromagnets interfacing piezoelectrics or ferroelectrics have shown enhanced multiferroic behaviour from effective strain coupling at the interface. In addition, nanostructuring of the ferroic phases has demonstrated further improvement in the coupling effect. Therefore, single-phase and engineered composite multiferroics consisting of complex metal oxides are reviewed in terms of magnetoelectric coupling effects and voltage controlled ferromagnetic properties, followed by a review on the integration challenges that need to be overcome to realize the

  12. Insights into organic carbon oxidation potential during fluvial transport from controlled laboratory and natural field experiments

    Science.gov (United States)

    Scheingross, Joel S.; Dellinger, Mathieu; Golombek, Nina; Hilton, Robert G.; Hovius, Niels; Sachse, Dirk; Turowski, Jens M.; Vieth-Hillebrand, Andrea; Wittmann, Hella

    2017-04-01

    Over geologic timescales, the exchange of organic carbon (OC) between the atmosphere, biosphere and geosphere is thought to be a major control on atmospheric carbon dioxide (CO2) concentrations, and hence global climate. The carbon fluxes from the oxidation of rock-derived OC (a CO2 source) and erosion and transport of biospheric OC (a potential CO2 sink) during fluvial transit are approximately the same order of magnitude or larger than those from silicate weathering (France-Lanord and Derry, 1997; Bouchez et al., 2010). Despite field data showing oxidation of OC moving downstream in lowland rivers, it is unclear if losses occur primarily during active fluvial transport within the river, where OC is in continual motion within an aerated environment, or during longer periods when OC is temporarily stored in river floodplains which may be anoxic. This represents a major knowledge gap, as the unknown location of OC oxidation (i.e., river vs. floodplain) limits our ability to develop process-based models that can be employed to predict OC losses, constrain carbon budgets, and unravel links between climate, tectonics, and erosion. To fill this gap, we investigated the potential for OC oxidation in both controlled laboratory experiments and a simplified field setting. We consider both rock-derived and biospheric OC. Our experiments simulated fluvial transport without floodplain storage, allowing mixtures of OC-rich and siliciclastic sediment to be transported for distances of 1000 km in annular flumes while making time-series measurements of OC concentration in both the solid (POC) and dissolved (DOC) loads, as well as measurements of rhenium concentration, which serves as a proxy for the oxidation of rock-derived OC. These transport experiments were compared to static, control experiments where water and sediment in the same proportion were placed in still water. Initial results for transport of OC-rich soil show similar behavior between the transport and static

  13. Selective oxidation of methionine residues in apolipoprotein A-I and its potential biological consequences

    International Nuclear Information System (INIS)

    Panzenboeck, U.; Waldeck, R.; Rye, K.A.; Sloane, T.; Kritharides, L.; Stocker, R.

    1998-01-01

    findings suggest that selective oxidation of Met residues of apo A-I may enhance rather than diminish known antiatherogenic activities of the apolipoprotein. Thus, our results are consistent with the overall hypothesis that detoxification of lipid hydroperoxides by Met residues of apo A-I is potentially antiatherogenic

  14. Effect of Collection Technique on Yield of Bovine Oocytes and the Development Potential of Oocytes from Different Grades of Oocytes

    Directory of Open Access Journals (Sweden)

    R.G Sianturi

    2002-10-01

    Full Text Available Oocyte collection technique is important to obtain a maximum number of oocytes to be employed on in vitro production of embryos. In this study, immature bovine oocytes were collected from slaughterhouse ovaries by two techniques: aspiration of 2- to 6-mm follicles and slicing. Following collection, oocyte qualities were classified into four categories (A, B, C, and D on the basis of cumulus attachment. Oocytes of each category were matured in vitro in CO2 incubator for 22-24 hours and cumulus expansion and maturation rates were observed. The total number of oocytes (group A+B+C+D and yield of good quality oocytes (only group A and B recovered per ovary by aspiration were 12.02 and 8.21, and by slicing were 29.38 and 19.65 (P<0.01, respectively. The total cumulus cells expansion rates of A, B, C and D oocytes were 97.1%, 88.3%, 6.0% and 20.6% respectively. Maturation rates for A, B and C categories of oocytes were 91.4%, 82.3% and 35.0% respectively while no matured oocyte was observed for group D oocytes. Maturation rates were significantly different between group A and C and also between B and C but not between A and B (P<0.05. In conclusion, slicing technique recovered more oocytes per ovary (2.4 times than that of aspiration and the best maturation rate was observed from category A oocytes which surrounded by more than 3 layers of cumulus cells. However oocytes of category A and B can be considered as good quality oocytes.

  15. Technical test description of activities to determine the potential for spent fuel oxidation in a tuff repository

    International Nuclear Information System (INIS)

    Einziger, R.E.

    1985-06-01

    The potential change in the oxidation state of spent fuel during its residence in a repository must be known to evaluate its radionuclide retention capabilities. Once the container breaches, the spent fuel in a repository sited above the water table will be exposed to a moist air atmosphere at low temperatures. Thermodynamically, there is no reason why the fuel should not oxidize to a higher oxidation state under these conditions, given enough time. Depending on the rate of oxidation, higher oxides with potentially higher leach rates may eventually form or the cladding may even split open. If either of these oxidation effects occurs, the ability of spent fuel to retard radionuclide migration will be reduced. A technical test description is presented to study spent fuel oxidation at low temperatures characteristic of the post-container breach period and at high temperatures in a moist inert atmosphere characteristic of a sealed container with waterlogged fuel, early in the repository life. The approach taken will be to perform tests and evaluations to gain understanding of the operative oxidation mechanisms, to obtain oxidation rate data, and to make projections of potential long-term fuel oxidation states. Time and temperature dependence of existing models will be evaluated, and the dependence of the model projections on fuel variables will be determined. 27 refs., 7 figs., 4 tabs

  16. Potential oxidative stress in the bodies of electric arc welding operators: effect of photochemical smog.

    Science.gov (United States)

    Zhu, You-Gen; Zhou, Jun-Fu; Shan, Wei-Ying; Zhou, Pei-Su; Tong, Gui-Zhong

    2004-12-01

    To investigate whether photochemical smog emitted during the process of electric arc welding might cause oxidative stress and potential oxidative damage in the bodies of welding operators. Seventy electric arc welding operators (WOs) and 70 healthy volunteers (HVs) were enrolled in a randomized controlled study design, in which the levels of vitamin C (VC) and vitamin E (VE) in plasma as well as the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and the level of lipoperoxide (LPO) in erythrocytes were determined by spectrophotometry. Compared with the average values of the above experimental parameters in the HVs group, the average values of VC and VE in plasma as well as those of SOD, CAT and GPX in erythrocytes in the WOs group were significantly decreased (P smog the values of VC, VE, SOD, and GPX, except for CAT, in the WOs were decreased gradually (P smog in the bodies of WOs, thereby causing potential oxidative and lipoperoxidative damages in their bodies.

  17. Role of groundwater oxidation potential and radiolysis on waste glass performance in crystalline repository environments

    International Nuclear Information System (INIS)

    Jantzen, C.M.; Bibler, N.E.

    1986-01-01

    Laboratory experiments have shown that groundwater conditions in a granite repository will be as reducing as those in a basalt repository. Chemical analysis of the reduced groundwaters confirmed that the Fe 2+ /Fe 3+ couple controls the oxidation potential (Eh). The reducing groundwater conditions were found to decrease the time-dependent release of soluble elements (Li and B) from the waste glass. However, due to the lower solubility of multivalent elements released from the glass when the groundwaters are reducing, these elements have significantly lower concentrations in the leachates. Gamma radiolysis reduced the oxidation potential of both granitic and basaltic groundwater in the absence of both waste glass and oxygen. This occurred in tests at atmospheric pressure where H 2 could have escaped from the solution. The mechanism for this decrease in Eh is under investigation but appears related to the reactive amorphous precipitate in both groundwaters. The results of these tests suggest that radiolysis may not cause the groundwaters to become oxidizing in a crystalline repository when abundant Fe 2+ species are present

  18. Chondroitin sulfate-capped super-paramagnetic iron oxide nanoparticles as potential carriers of doxorubicin hydrochloride.

    Science.gov (United States)

    Mallick, Neha; Anwar, Mohammed; Asfer, Mohammed; Mehdi, Syed Hassan; Rizvi, Mohammed Moshahid Alam; Panda, Amulya Kumar; Talegaonkar, Sushama; Ahmad, Farhan Jalees

    2016-10-20

    Chondroitin-4-sulfate (CS), a glycosaminoglycan, was used to prepare CS-capped super-paramagnetic iron oxide nanoparticles, which were further employed for loading a water-soluble chemotherapeutic agent (doxorubicin hydrochloride, DOX). CS-capped SPIONs have potential biomedical application in cancer targeting. The optimized formulation had a hydrodynamic size of 91.2±0.8nm (PDI; 0.228±0.004) and zeta potential of -49.1±1.66mV. DOX was loaded onto the formulation up to 2% (w/w) by physical interaction with CS. TEM showed nano-sized particles having a core-shell structure. XRD confirmed crystal phase of iron oxide. FT-IR conceived the interaction of iron oxide with CS as bidentate chelation and also confirmed DOX loading. Vibration sample magnetometry confirmed super-paramagnetic nature of nanoparticles, with saturation magnetization of 0.238emug(-1). In vitro release profile at pH 7.4 showed that 96.67% of DOX was released within 24h (first order kinetics). MTT assay in MCF7 cells showed significantly higher (p<0.0001) cytotoxicity for DOX in SPIONs than DOX solution (IC50 values 6.294±0.4169 and 11.316±0.1102μgmL(-1), respectively). Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Potential Biomarker of Myofibrillar Protein Oxidation in Raw and Cooked Ham: 3-Nitrotyrosine Formed by Nitrosation.

    Science.gov (United States)

    Feng, Xianchao; Li, Chenyi; Ullah, Niamat; Hackman, Robert M; Chen, Lin; Zhou, Guanghong

    2015-12-30

    The stability of cured meat products is increased by the protection of its proteins from oxidation by sodium nitrite (NaNO2) during processing. This study investigated the effects of NaNO2 (0, 50, 100, 200, and 400 mg/kg) on the physiochemical and structural characteristics of myofibrillar protein (MP) in raw and cooked ham. The NaNO2 showed a dose-dependent antioxidant effect, by inhibiting carbonyl formation, dityrosine formation, and denaturation of MP, and a nitrosative effect, through the formation of 3-Nitrotyrosine (3-NT). The 3-NT content within MP of raw ham had distinct negative correlations with sulfhydryl content and surface hydrophobicity. The 3-NT content within MP of cooked ham had significantly negative correlations with carbonyl, sulfhydryl content and turbidity and had significantly positive correlations with disulfide content. These results indicated that 3-NT may be a potential marker for protein oxidation in raw and cooked cured meat products.

  20. Ethylene oxide gas sterilization does not reduce the osteoinductive potential of demineralized bone in rats

    DEFF Research Database (Denmark)

    Solheim, E; Pinholt, E M; Bang, G

    1995-01-01

    It has been shown that different sterilization procedures of demineralized bone may influence its osteoinductive properties. The aim of this study was to evaluate the effect of ethylene oxide sterilization for 1, 3, and 6 hours on the osteoinductive potential of allogeneic demineralized bone...... implanted heterotopically in rats. Sixty male Wistar rats were randomly assigned to one of four groups, A through D, and four demineralized bone chips (2.8 mg) were implanted in a pouch created between the right oblique abdominal muscles in each animal. In Group A, the demineralized bone was implanted...... without prior sterilization of the material, whereas the demineralized bone implanted in Groups B, C, and D had been sterilized in ethylene oxide gas for 1, 3, or 6 hours, respectively, and aerated for 48 hours. At 4 weeks postoperatively, bone formation was evaluated quantitatively by strontium 85 uptake...

  1. Equity yields

    NARCIS (Netherlands)

    Vrugt, E.; van Binsbergen, J.H.; Koijen, R.S.J.; Hueskes, W.

    2013-01-01

    We study a new data set of dividend futures with maturities up to ten years across three world regions: the US, Europe, and Japan. We use these asset prices to construct equity yields, analogous to bond yields. We decompose the equity yields to obtain a term structure of expected dividend growth

  2. Altered lipoproteins in patients with systemic lupus erythematosus are associated with augmented oxidative stress: a potential role in atherosclerosis.

    Science.gov (United States)

    Park, Jin Kyun; Kim, Jae-Yong; Moon, Jin Young; Ahn, Eun Young; Lee, Eun Young; Lee, Eun Bong; Cho, Kyung-Hyun; Song, Yeong Wook

    2016-12-30

    To examine the structural and oxidative properties of lipoproteins from patients with systemic lupus erythematosus (SLE). The lipid profiles of 35 SLE patients and 15 healthy controls (HCs) were compared. Oxidation status, susceptibility to oxidation, and structural integrity of low-density lipoprotein (LDL) were determined by measuring malondialdehyde (MDA), de novo formation of conjugated dienes in the presence of CuSO 4 , and mobility on gel electrophoresis, respectively. In vitro foam cell formation and the oxidative potential in zebrafish embryos were examined. LDL levels in SLE patients and HCs were similar (p = 0.277). LDL from SLE patients was more fragmented than that from HCs. In addition, LDL from SLE patients was more oxidized than LDL from HCs (p Lipoproteins from SLE patients exhibited greater oxidative potential, which might contribute to accelerated atherosclerosis in SLE.

  3. The effect of NaOH catalyst concentration and extraction time on the yield and properties of Citrullus vulgaris seed oil as a potential biodiesel feed stock

    Directory of Open Access Journals (Sweden)

    J.K. Efavi

    2018-06-01

    Full Text Available In this work, oil was extracted from Citrullus vulgaris (watermelon seeds for potential feedstock in biodiesel production. The results showed that, the oil content from Citrullus vulgaris seeds oil during extraction reached an average yield of 50%. Biodiesel was produced via transesterification using NaOH as catalyst. The effect of NaOH on the yield of the biodiesel was investigated at three different concentrations; 0.13, 0.15 and 0.18 g and oil to methanol ratio of 5:1 under different reaction times; 90, 120 and 150 min at 60 °C. The yield of biodiesel from NaOH concentration of 0.13 g was found to be 70% as compared to those of concentrations, 0.15 g and 0.18 g which were 53% and 49% respectively.Gas chromatography was used to identify the methyl ester groups present in the biodiesel and the results revealed both concentration and time-dependent increase in oil yield. The physicochemical properties of the watermelon seed oil such as flash point (141.3 ± 0.4–143.4 ± 0.2, density (0.86 ± 0.04–0.91 ± 0.01 g/cm3, kinematic viscosity (30.50 ± 0.1–31.20 ± 0.04 mm2/s and acid value (mg KOH/g are similar to conventional vegetable oils. This work therefore, highlights the potential utility of water melon seeds for biodiesel production. Keywords: Citrullus vulgaris, Gas chromatography, Catalyst

  4. Oxidative dissolution potential of biogenic and abiogenic TcO2 in subsurface sediments

    International Nuclear Information System (INIS)

    Fredrickson, J.K.; Zachara, J.M.; Plymale, A.E.; Heald, S.M.; McKinley, J.P.; Kennedy, D.W.; Liu, C.; Nachimuthu, P.

    2009-01-01

    Technetium-99 (Tc) is an important fission product contaminant associated with sites of nuclear fuels reprocessing and geologic nuclear waste disposal. Tc is highly mobile in its most oxidized state (Tc(VII)O 4 - ) and less mobile in the reduced form (Tc(IV)O 2 · nH 2 O). Here we investigate the potential for oxidation of Tc(IV) that was heterogeneously reduced by reaction with biogenic Fe(II) in two sediments differing in mineralogy and aggregation state; unconsolidated Pliocene-age fluvial sediment from the upper Ringold (RG) Formation at the Hanford Site and a clay-rich saprolite from the Field Research Center (FRC) background site on the Oak Ridge Site. Both sediments contained Fe(III) and Mn(III/IV) as redox active phases, but FRC also contained mass-dominant Fe-phyllosilicates of different types. Shewanella putrefaciens CN32 reduced Mn(III/IV) oxides and generated Fe(II) that was reactive with Tc(VII) in heat-killed, bioreduced sediment. After bioreduction and heat-killing, biogenic Fe(II) in the FRC exceeded that in RG by a factor of two. More rapid reduction rates were observed in the RG that had lower biogenic Fe(II), and less particle aggregation. EXAFS measurements indicated that the primary reduction product was a TcO 2 -like phase in both sediments. The biogenic redox product Tc(IV) oxidized rapidly and completely in RG when contacted with air. Oxidation, in contrast, was slow and incomplete in the FRC, in spite of similar molecular scale speciation of Tc compared to RG. X-ray microprobe, electron microprobe, X-ray absorption spectroscopy, and micro X-ray diffraction were applied to the whole sediment and isolated Tc-containing particles. These analyses revealed that non-oxidizable Tc(IV) in the FRC existed as complexes with octahedral Fe(III) within intra-grain domains of 50-100 (micro)m-sized, Fe-containing micas presumptively identified as celadonite. The markedly slower oxidation rates in FRC as compared to RG were attributed to mass

  5. Oxidative dissolution potential of biogenic and abiogenic TcO 2 in subsurface sediments

    Science.gov (United States)

    Fredrickson, James K.; Zachara, John M.; Plymale, Andrew E.; Heald, Steve M.; McKinley, James P.; Kennedy, David W.; Liu, Chongxuan; Nachimuthu, Ponnusamy

    2009-04-01

    Technetium-99 (Tc) is an important fission product contaminant associated with sites of nuclear fuels reprocessing and geologic nuclear waste disposal. Tc is highly mobile in its most oxidized state [Tc(VII)O4-] and less mobile in the reduced form [Tc(IV)O 2· nH 2O]. Here we investigate the potential for oxidation of Tc(IV) that was heterogeneously reduced by reaction with biogenic Fe(II) in two sediments differing in mineralogy and aggregation state; unconsolidated Pliocene-age fluvial sediment from the upper Ringold (RG) Formation at the Hanford Site and a clay-rich saprolite from the Field Research Center (FRC) background site on the Oak Ridge Site. Both sediments contained Fe(III) and Mn(III/IV) as redox active phases, but FRC also contained mass-dominant Fe-phyllosilicates of different types. Shewanella putrefaciens CN32 reduced Mn(III/IV) oxides and generated Fe(II) that was reactive with Tc(VII) in heat-killed, bioreduced sediment. After bioreduction and heat-killing, biogenic Fe(II) in the FRC exceeded that in RG by a factor of two. More rapid reduction rates were observed in the RG that had lower biogenic Fe(II), and less particle aggregation. EXAFS measurements indicated that the primary reduction product was a TcO 2-like phase in both sediments. The biogenic redox product Tc(IV) oxidized rapidly and completely in RG when contacted with air. Oxidation, in contrast, was slow and incomplete in the FRC, in spite of similar molecular scale speciation of Tc compared to RG. X-ray microprobe, electron microprobe, X-ray absorption spectroscopy, and micro X-ray diffraction were applied to the whole sediment and isolated Tc-containing particles. These analyses revealed that non-oxidizable Tc(IV) in the FRC existed as complexes with octahedral Fe(III) within intra-grain domains of 50-100 μm-sized, Fe-containing micas presumptively identified as celadonite. The markedly slower oxidation rates in FRC as compared to RG were attributed to mass

  6. Modeling organic aerosol from the oxidation of α-pinene in a Potential Aerosol Mass (PAM chamber

    Directory of Open Access Journals (Sweden)

    S. Chen

    2013-05-01

    Full Text Available A model has been developed to simulate the formation and evolution of secondary organic aerosol (SOA and was tested against data produced in a Potential Aerosol Mass (PAM flow reactor and a large environmental chamber. The model framework is based on the two-dimensional volatility basis set approach (2D-VBS, in which SOA oxidation products in the model are distributed on the 2-D space of effective saturation concentration (Ci* and oxygen-to-carbon ratio (O : C. The modeled organic aerosol mass concentrations (COA and O : C agree with laboratory measurements within estimated uncertainties. However, while both measured and modeled O : C increase with increasing OH exposure as expected, the increase of modeled O : C is rapid at low OH exposure and then slows as OH exposure increases while the increase of measured O : C is initially slow and then accelerates as OH exposure increases. A global sensitivity analysis indicates that modeled COA values are most sensitive to the assumed values for the number of Ci* bins, the heterogeneous OH reaction rate coefficient, and the yield of first-generation products. Modeled SOA O : C values are most sensitive to the assumed O : C of first-generation oxidation products, the number of Ci* bins, the heterogeneous OH reaction rate coefficient, and the number of O : C bins. All these sensitivities vary as a function of OH exposure. The sensitivity analysis indicates that the 2D-VBS model framework may require modifications to resolve discrepancies between modeled and measured O : C as a function of OH exposure.

  7. Interface bonding in silicon oxide nanocontacts: interaction potentials and force measurements

    Science.gov (United States)

    Wierez-Kien, M.; Craciun, A. D.; Pinon, A. V.; Le Roux, S.; Gallani, J. L.; Rastei, M. V.

    2018-04-01

    The interface bonding between two silicon-oxide nanoscale surfaces has been studied as a function of atomic nature and size of contacting asperities. The binding forces obtained using various interaction potentials are compared with experimental force curves measured in vacuum with an atomic force microscope. In the limit of small nanocontacts (typically contact area which is altered by stretching speeds. The mean unbinding force is found to decrease as the contact spends time in the attractive regime. This contact weakening is featured by a negative aging coefficient which broadens and shifts the thermal-induced force distribution at low stretching speeds.

  8. Calculated ionisation potentials to determine the oxidation of vanillin precursors by lignin peroxidase.

    OpenAIRE

    Have, ten, R.; Rietjens, I.M.C.M.; Hartmans, S.; Swarts, H.J.; Field, J.A.

    1998-01-01

    In view of the biocatalytic production of vanillin, this research focused on the lignin peroxidase (LiP) catalysed oxidation of naturally occurring phenolic derivatives: O-methyl ethers, O-acetyl esters, and O-glucosyl ethers. The ionisation potential (IP) of a series of model compounds was calculated and compared to their experimental conversion by LiP, defining a relative IP threshold of approximately 9.0 eV. Based on this threshold value only the O-acetyl esters and glucosides of isoeugeno...

  9. A review of the industrial and recent potential applications of trioctylphosphine oxide

    International Nuclear Information System (INIS)

    Watson, E.K.; Rickelton, W.A.

    1992-01-01

    The industrial applications of trioctylphosphine oxide, more commonly known as TOPO, make use of its complexing powers with metals and with hydrogen donor organic compounds. Commercial uses as a solvent extraction reagent are in the recovery of uranium from wet process phosphoric acid and in the recovery of byproduct acetic acid and furfural generated during sulphite wood pulping. Recently investigated potential uses include the separation of niobium from tantalum and the extraction of organic compounds, such as citric acid, from fermentation broths. Each process is discussed briefly. 29 refs., 2 figs

  10. Root yield and reserpine content of Rauvolfia serpentina Benth. on media under the plant with potential allelopathic effect by nutrient addition

    Directory of Open Access Journals (Sweden)

    SULANDJARI

    2008-07-01

    Full Text Available The root of Rauvolfia serpentina Benth (pule pandak contains more than 50 kinds of alkaloid which is useful to treat many kinds of diseases and reserpine is ones to treat of hypertension. Eucalyptus deglupta and Acacia mangium have become release an allelochemy to ecosystem that are can reduce the growth of the plant association. The purpose of this research is to know about the influence of nutrient and media under the plant with potential allelopathic effect to root yield and reserpine content. The research was arranged in Complete Random Block Design. Nutrient was nested on media. Media are: under Tectona grandis, A. mangium, and E. deglupta. Nutrient is 30 t ha-1 organic fertilizers, 200 ha-1 inorganic (NPK fertilizers and control. Polybag with 30 cmx30 cm plant densities and 20% of shading. The result are that beside under the T. grandis, pule pandak was capable to growth under the A. mangium and E. deglupta. Thirty ton per hectare organic fertilizers was increased of growth and yield more than 200 ha-1 inorganic (NPK fertilizers. Allelocemy from A. mangium and E. deglupta was decreased dry root yield but was not effect to reserpine content.

  11. Mapping the Lisbon Potential Foodshed in Ribatejo e Oeste: A Suitability and Yield Model for Assessing the Potential for Localized Food Production

    Directory of Open Access Journals (Sweden)

    Andreia Saavedra Cardoso

    2017-11-01

    Full Text Available Research on food planning has been recently proposed in North American and European planning to account for how cities might change their food provision to respond to the rising demands for a more sustainable and ethical food system. The purpose of this paper was to evaluate the agro-ecological potential of the Lisbon city region, Ribatejo e Oeste, to increase its Regional Food Self-Reliance (RFSR, through adopting demand restraint and food system relocalization approaches to food system sustainability. Three new diet scenarios were considered: meat-based, plant-based and strict vegetarian, defined in accordance with healthy dietary patterns. We used agro-climatic and agro-edaphic agricultural suitability models to evaluate the agro-ecological potential for RFSR, and proposed the use of Foodshed Landscape Plans within a landscape planning methodology. Results showed the extent of local food production that could improve food self-reliance, with 72%, 76%, 84% of total food needs in the meat-based, plant-based, and strict vegetarian scenarios, respectively. Thus, food system transformation by means of relocalization, is therefore ecologically feasible and would ensure the sustainable use of the ecological basis of food security. Additionally, a dietary transition would imply significant land sparing, which strengthens the demand restraint perspective for a transition to food system sustainability.

  12. Hydrogen Peroxide Cycling in Acidic Geothermal Environments and Potential Implications for Oxidative Stress

    Science.gov (United States)

    Mesle, M.; Beam, J.; Jay, Z.; Bodle, B.; Bogenschutz, E.; Inskeep, W.

    2014-12-01

    Hydrogen peroxide (H2O2) may be produced in natural waters via photochemical reactions between dissolved oxygen, organic carbon and light. Other reactive oxygen species (ROS) such as superoxide and hydroxyl radicals are potentially formed in environments with high concentrations of ferrous iron (Fe(II), ~10-100 μM) by reaction between H2O2 and Fe(II) (i.e., Fenton chemistry). Thermophilic archaea and bacteria inhabiting acidic iron-oxide mats have defense mechanisms against both extracellular and intracellular peroxide, such as peroxiredoxins (which can degrade H2O2) and against other ROS, such as superoxide dismutases. Biological cycling of H2O2 is not well understood in geothermal ecosystems, and geochemical measurements combined with molecular investigations will contribute to our understanding of microbial response to oxidative stress. We measured H2O2 and other dissolved compounds (Fe(II), Fe(III), H2S, O2), as well as photon flux, pH and temperature, over time in surface geothermal waters of several acidic springs in Norris Geyser Basin, Yellowstone National Park, WY (Beowulf Spring and One Hundred Spring Plain). Iron-oxide mats were sampled in Beowulf Spring for on-going analysis of metatranscriptomes and RT-qPCR assays of specific stress-response gene transcription (e.g., superoxide dismutases, peroxiredoxins, thioredoxins, and peroxidases). In situ analyses show that H2O2 concentrations are lowest in the source waters of sulfidic systems (ca. 1 μM), and increase by two-fold in oxygenated waters corresponding to Fe(III)-oxide mat formation (ca. 2 - 3 μM). Channel transects confirm increases in H2O2 as a function of oxygenation (distance). The temporal dynamics of H2O2, O2, Fe(II), and H2S in Beowulf geothermal waters were also measured during a diel cycle, and increases in H2O2 were observed during peak photon flux. These results suggest that photochemical reactions may contribute to changes in H2O2. We hypothesize that increases in H2O2 and O2

  13. Experimental insights into organic carbon oxidation potential during fluvial transport without floodplain storage

    Science.gov (United States)

    Scheingross, J. S.; Hovius, N.; Sachse, D.; Vieth-Hillebrand, A.; Turowski, J. M.; Hilton, R. G.

    2016-12-01

    Over geologic timescales, the exchange of organic carbon (OC) between the atmosphere, rock, and biosphere is thought to be a major control on global climate. CO2 flux estimates from oxidation of rock-derived OC and sequestration of biospheric OC during fluvial transit from source to sink are approximately the same order of magnitude or larger than those from silicate weathering. Despite field data showing loss of OC moving downstream in lowland rivers, it is unclear if losses occur primarily during active fluvial transport within the river, where OC is in continual motion within an aerated environment, or during longer periods when OC is temporarily stored in river floodplains which may be anoxic. This represents a major knowledge gap, as the unknown location of OC oxidation (i.e., river vs. floodplain) limits our ability to develop process-based models that can be employed to predict OC losses, constrain carbon budgets, and unravel links between climate, tectonics, and erosion. To fill this gap, we investigated the potential for OC oxidation in laboratory experiments simulating fluvial transport without floodplain storage. Mixtures of OC-rich and siliciclastic sediment were transported for distances of 2000 km in annular flumes while making time-series measurements of sediment TOC and water DOC concentrations. Initial results for transport of OC-rich soil show increasing DOC with transport distance to levels that represent a transfer of 2% of the total OC from the solid to the dissolved phase; however, we observed no detectable change in the solid-phase TOC. Similar results were obtained in a control experiment with identical sediment in still water. These preliminary results suggest minimal OC oxidation within our experiment, and, to the extent that such experiments represent natural transport through river systems, are consistent with the hypothesis that OC losses may occur primarily during floodplain storage rather than fluvial transport.

  14. Long interspersed nuclear element-1 hypomethylation and oxidative stress: correlation and bladder cancer diagnostic potential.

    Directory of Open Access Journals (Sweden)

    Maturada Patchsung

    Full Text Available Although, increased oxidative stress and hypomethylation of long interspersed nuclear element-1 (LINE-1 associate with bladder cancer (BCa development, the relationship between these alterations is unknown. We evaluated the oxidative stress and hypomethylation of the LINE-1 in 61 BCa patients and 45 normal individuals. To measure the methylation levels and to differentiate the LINE-1 loci into hypermethylated, partially methylated and hypomethylated, peripheral blood cells, urinary exfoliated cells and cancerous tissues were evaluated by combined bisulfite restriction analysis PCR. The urinary total antioxidant status (TAS and plasma protein carbonyl content were determined. The LINE-1 methylation levels and patterns, especially hypomethylated loci, in the blood and urine cells of the BCa patients were different from the levels and patterns in the healthy controls. The urinary TAS was decreased, whereas the plasma protein carbonyl content was increased in the BCa patients relative to the controls. A positive correlation between the methylation of LINE-1 in the blood-derived DNA and urinary TAS was found in both the BCa and control groups. The urinary hypomethylated LINE-1 loci and the plasma protein carbonyl content provided the best diagnostic potential for BCa prediction. Based on post-diagnostic samples, the combination test improved the diagnostic power to a sensitivity of 96% and a specificity of 96%. In conclusion, decreased LINE-1 methylation is associated with increased oxidative stress both in healthy and BCa subjects across the various tissue types, implying a dose-response association. Increases in the LINE-1 hypomethylation levels and the number of hypomethylated loci in both the blood- and urine-derived cells and increase in the oxidative stress were found in the BCa patients. The combination test of the urinary hypomethylated LINE-1 loci and the plasma protein carbonyl content may be useful for BCa screening and monitoring of

  15. A preliminary exploration of the potential of Eugenia uvalha Cambess juice intake to counter oxidative stress.

    Science.gov (United States)

    Lopes, J M M; Lage, N N; Guerra, J F C; Silva, M; Bonomo, L F; Paulino, A H S; Regis, A L R S; Pedrosa, M L; Silva, M E

    2018-03-01

    The ability of foods to aid in the prevention of chronic metabolic diseases, has recently become an area of increased interest. In addition, there is growing interest in exploring the benefits of consuming underutilized fruits as alternatives to commercially available fruits. Eugenia uvalha Cambess (uvaia) is a native fruit of Brazil with great market and phytotherapy potential. The present study was conducted to investigate the effects of uvaia juice (UJ) on the levels of protein carbonyls (PCO) and antioxidant enzymes in the livers of rats fed a high-fat diet. Thirty-two female rats were randomly assigned to four groups. The rats were fed either a standard diet (group C) or a high-fat diet (group HF). In addition, groups CUJ and HFUJ were treated with UJ (2mL/day) administered via gavage for 8weeks. In our study, UJ displayed high antioxidant activity (135.14±9.74 GAE/100g). Administration of UJ caused a significantly reduced concentration of rat liver PCO (47.4%), which was associated with a 29% increase in catalase activity. A significant increase in the concentration of oxidized glutathione (GSSG) (15.04±5.08nmol/ml) and a reduction in the reduced glutathione/oxidized glutathione ratio (GSH/GSSG) (11.30±2.68) were found in the HF group, whilst these changes were not observed in the HFUJ group (a result similar to that of group C). Our results demonstrate that UJ decreases oxidative damage by improving antioxidant efficiency and attenuating oxidative damage to proteins. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Relationship between chemical composition and oxidative potential of secondary organic aerosol from polycyclic aromatic hydrocarbons

    Science.gov (United States)

    Wang, Shunyao; Ye, Jianhuai; Soong, Ronald; Wu, Bing; Yu, Legeng; Simpson, André J.; Chan, Arthur W. H.

    2018-03-01

    Owing to the complex nature and dynamic behaviors of secondary organic aerosol (SOA), its ability to cause oxidative stress (known as oxidative potential, or OP) and adverse health outcomes remains poorly understood. In this work, we probed the linkages between the chemical composition of SOA and its OP, and investigated impacts from various SOA evolution pathways, including atmospheric oligomerization, heterogeneous oxidation, and mixing with metal. SOA formed from photooxidation of the two most common polycyclic aromatic hydrocarbons (naphthalene and phenanthrene) were studied as model systems. OP was evaluated using the dithiothreitol (DTT) assay. The oligomer-rich fraction separated by liquid chromatography dominates DTT activity in both SOA systems (52 ± 10 % for naphthalene SOA (NSOA), and 56 ± 5 % for phenanthrene SOA (PSOA)). Heterogeneous ozonolysis of NSOA was found to enhance its OP, which is consistent with the trend observed in selected individual oxidation products. DTT activities from redox-active organic compounds and metals were found to be not additive. When mixing with highly redox-active metal (Cu), OP of the mixture decreased significantly for 1,2-naphthoquinone (42 ± 7 %), 2,3-dihydroxynaphthalene (35 ± 1 %), NSOA (50 ± 6 %), and PSOA (43 ± 4 %). Evidence from proton nuclear magnetic resonance (1H NMR) spectroscopy illustrates that such OP reduction upon mixing can be ascribed to metal-organic binding interactions. Our results highlight the role of aerosol chemical composition under atmospheric aging processes in determining the OP of SOA, which is needed for more accurate and explicit prediction of the toxicological impacts from particulate matter.

  17. Potential forcing of CO2, technology and climate changes in maize (Zea mays) and bean (Phaseolus vulgaris) yield in southeast Brazil

    International Nuclear Information System (INIS)

    Costa, L C; Justino, F; Oliveira, L J C; Sediyama, G C; Lemos, C F; Ferreira, W P M

    2009-01-01

    Based upon sensitivity experiments, this study aims to investigate the impact of increased atmospheric CO 2 concentration, climate changes, and ongoing technological advancements on bean (Phaseolus vulgaris) and maize (Zea mays) yield. This investigation assumes that the atmospheric CO 2 concentration evolves according to the A2 scenario. For these analyses we have used climate data as projected by climate simulations conducted with the HadCM3 climate model for both present day and greenhouse warming conditions. The results demonstrated that warming conditions associated with increased greenhouse gases as delivered by the HadCM3 model lead to reductions in the potential productivity of maize and beans for the years 2050 and 2080 by up to 30%. This thermal response is, however, damped by the highly efficient CO 2 fertilization effect which is expected to increase bean productivity as compared to present day conditions. A similar investigation for maize yield revealed a different picture. It has been found that the CO 2 fertilization feedback is much weaker and cannot cancel out the thermal effect. We have found, therefore, that climate changes as simulated to occur in the future are not favorable for increasing the maize yield in southeast Brazil. By the inclusion of the third forcing evaluated, representing technological advancements, it is demonstrated that improvements in the crop system reduce the negative effect associated with warmer climate conditions for both crops. We conclude that appropriate soil and technological management as well as genetic improvements may very likely induce an increase in bean and maize yield despite the unfavorable future climate conditions.

  18. Potential forcing of CO{sub 2}, technology and climate changes in maize (Zea mays) and bean (Phaseolus vulgaris) yield in southeast Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Costa, L C; Justino, F; Oliveira, L J C; Sediyama, G C; Lemos, C F [Department of Agricultural Engineering, Federal University of Vicosa, PH Rolfs S/N, Vicosa, MG, 36570 000 (Brazil); Ferreira, W P M [Embrapa Milho e Sorgo, Rodovia MG 424, km 45, Caixa Postal 285, CEP 35701-970 Sete Lagoas, MG (Brazil)], E-mail: fjustino@ufv.br

    2009-01-15

    Based upon sensitivity experiments, this study aims to investigate the impact of increased atmospheric CO{sub 2} concentration, climate changes, and ongoing technological advancements on bean (Phaseolus vulgaris) and maize (Zea mays) yield. This investigation assumes that the atmospheric CO{sub 2} concentration evolves according to the A2 scenario. For these analyses we have used climate data as projected by climate simulations conducted with the HadCM3 climate model for both present day and greenhouse warming conditions. The results demonstrated that warming conditions associated with increased greenhouse gases as delivered by the HadCM3 model lead to reductions in the potential productivity of maize and beans for the years 2050 and 2080 by up to 30%. This thermal response is, however, damped by the highly efficient CO{sub 2} fertilization effect which is expected to increase bean productivity as compared to present day conditions. A similar investigation for maize yield revealed a different picture. It has been found that the CO{sub 2} fertilization feedback is much weaker and cannot cancel out the thermal effect. We have found, therefore, that climate changes as simulated to occur in the future are not favorable for increasing the maize yield in southeast Brazil. By the inclusion of the third forcing evaluated, representing technological advancements, it is demonstrated that improvements in the crop system reduce the negative effect associated with warmer climate conditions for both crops. We conclude that appropriate soil and technological management as well as genetic improvements may very likely induce an increase in bean and maize yield despite the unfavorable future climate conditions.

  19. Potential for iron oxides to control metal releases in CO2 sequestration scenarios

    Science.gov (United States)

    Berger, P.M.; Roy, W.R.

    2011-01-01

    The potential for the release of metals into groundwater following the injection of carbon dioxide (CO2) into the subsurface during carbon sequestration projects remains an open research question. Changing the chemical composition of even the relatively deep formation brines during CO2 injection and storage may be of concern because of the recognized risks associated with the limited potential for leakage of CO2-impacted brine to the surface. Geochemical modeling allows for proactive evaluation of site geochemistry before CO2 injection takes place to predict whether the release of metals from iron oxides may occur in the reservoir. Geochemical modeling can also help evaluate potential changes in shallow aquifers were CO2 leakage to occur near the surface. In this study, we created three batch-reaction models that simulate chemical changes in groundwater resulting from the introduction of CO2 at two carbon sequestration sites operated by the Midwest Geological Sequestration Consortium (MGSC). In each of these models, we input the chemical composition of groundwater samples into React??, and equilibrated them with selected mineral phases and CO 2 at reservoir pressure and temperature. The model then simulated the kinetic reactions with other mineral phases over a period of up to 100 years. For two of the simulations, the water was also at equilibrium with iron oxide surface complexes. The first model simulated a recently completed enhanced oil recovery (EOR) project in south-central Illinois in which the MGSC injected into, and then produced CO2, from a sandstone oil reservoir. The MGSC afterwards periodically measured the brine chemistry from several wells in the reservoir for approximately two years. The sandstone contains a relatively small amount of iron oxide, and the batch simulation for the injection process showed detectable changes in several aqueous species that were attributable to changes in surface complexation sites. After using the batch reaction

  20. Indium oxide thin film as potential photoanodes for corrosion protection of stainless steel under visible light

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yan [Key Laboratory of New Fiber Materials and Modern Textile, Qingdao University, 308 Ningxia Road, Qingdao 266071 (China); Yu, Jianqiang, E-mail: jianqyu@qdu.edu.cn [Key Laboratory of New Fiber Materials and Modern Textile, Qingdao University, 308 Ningxia Road, Qingdao 266071 (China); Sun, Kai; Zhu, Yukun [Key Laboratory of New Fiber Materials and Modern Textile, Qingdao University, 308 Ningxia Road, Qingdao 266071 (China); Bu, Yuyu; Chen, Zhuoyuan [National Engineering Center of Marine Corrosion Protection, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071 (China)

    2014-05-01

    Graphical abstract: If the conduction band potential of In{sub 2}O{sub 3} is more negative than the corrosion potential of stainless steel, photo-induced electrons will be transferred from In{sub 2}O{sub 3} to the steel, thus shifting the potential of the steel into a corrosion immunity region and preventing the steel from the corrosion. - Highlights: • Indium oxide performed novel application under visible light. • Indium oxide by sol–gel method behaved better photoelectrochemical properties. • Electrons were transferred to stainless steel from indium oxide once light on. - Abstract: This paper reports the photoelectrochemical cathodic protection of 304 stainless steel by In{sub 2}O{sub 3} thin-film under visible-light. The films were fabricated with In{sub 2}O{sub 3} powders, synthesized by both sol–gel (In{sub 2}O{sub 3}-sg) and solid-state (In{sub 2}O{sub 3}-ss) processes. The photo-induced open circuit potential and the photo-to-current efficiency measurements suggested that In{sub 2}O{sub 3} could be a promising candidate material for photoelectrochemical cathodic protection of metallic alloys under visible light. Moreover, the polarization curve experimental results indicated that In{sub 2}O{sub 3}-sg thin-film can mitigate the corrosion potential of 304 stainless steel to much more negative values with a higher photocurrent density than the In{sub 2}O{sub 3}-ss film under visible-light illumination. All the results demonstrated that the In{sub 2}O{sub 3}-sg thin-film provides a better photoelectrochemical cathodic protection for 304 stainless steel than In{sub 2}O{sub 3}-ss thin-film under visible-light illumination. The higher photoelectrochemical efficiency is possibly due to the uniform thin films produced with the smaller particle size of In{sub 2}O{sub 3}-sg, which facilitates the transfer of the photo-induced electrons from bulk to the surface and suppresses the charge recombination of the electrons and holes.

  1. Construction of an interatomic potential for zinc oxide surfaces by high-dimensional neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Artrith, Nongnuch; Morawietz, Tobias; Behler, Joerg [Lehrstuhl fuer Theoretische Chemie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

    2011-07-01

    Zinc oxide (ZnO) is a technologically important material with many applications, e.g. in heterogeneous catalysis. For theoretical studies of the structural properties of ZnO surfaces, defects, and crystal structures it is necessary to simulate large systems over long time-scales with sufficient accuracy. Often, the required system size is not accessible by computationally rather demanding density-functional theory (DFT) calculations. Recently, artificial Neural Networks (NN) trained to first principles data have shown to provide accurate potential-energy surfaces (PESs) for condensed systems. We present the construction and analysis of a NN PES for ZnO. The structural and energetic properties of bulk ZnO and ZnO surfaces are investigated using this potential and compared to DFT calculations.

  2. Ab initio intermolecular potential energy surface and thermophysical properties of nitrous oxide.

    Science.gov (United States)

    Crusius, Johann-Philipp; Hellmann, Robert; Hassel, Egon; Bich, Eckard

    2015-06-28

    We present an analytical intermolecular potential energy surface (PES) for two rigid nitrous oxide (N2O) molecules derived from high-level quantum-chemical ab initio calculations. Interaction energies for 2018 N2O-N2O configurations were computed utilizing the counterpoise-corrected supermolecular approach at the CCSD(T) level of theory using basis sets up to aug-cc-pVQZ supplemented with bond functions. A site-site potential function with seven sites per N2O molecule was fitted to the pair interaction energies. We validated our PES by computing the second virial coefficient as well as shear viscosity and thermal conductivity in the dilute-gas limit. The values of these properties are substantiated by the best experimental data.

  3. Oxidative stress protection by newly synthesized nitrogen compounds with pharmacological potential.

    Science.gov (United States)

    Silva, João P; Areias, Filipe M; Proença, Fernanda M; Coutinho, Olga P

    2006-02-09

    In this study we used new nitrogen compounds obtained by organic synthesis whose structure predicted an antioxidant potential and then an eventual development as molecules of pharmacological interest in diseases involving oxidative stress. The compounds, identified as FMA4, FMA5, FMA7 and FMA8 differ in the presence of hydroxyl groups located in the C-3 and/or C-4 position of a phenolic unit, which is possibly responsible for their free radicals' buffering capacity. Data from the DPPH discoloration method confirm the high antiradical efficiency of the compounds. The results obtained with cellular models (L929 and PC12) show that they are not toxic and really protect from membrane lipid peroxidation induced by the ascorbate-iron oxidant pair. The level of protection correlates with the drug's lipophilic profile and is sometimes superior to trolox and equivalent to that observed for alpha-tocopherol. The compounds FMA4 and FMA7 present also a high protection from cell death evaluated in the presence of a staurosporine apoptotic stimulus. That protection results in a significant reduction of caspase-3 activity induced by staurosporine which by its turn seems to result from a protection observed in the membrane receptor pathway (caspase-8) together with a protection observed in the mitochondrial pathway (caspase-9). Taken together the results obtained with the new compounds, with linear chains, open up perspectives for their use as therapeutical agents, namely as antioxidants and protectors of apoptotic pathways. On the other hand the slight pro-oxidant profile obtained with the cyclic structures suggests a different therapeutic potential that is under current investigation.

  4. Potential of plant polyphenols to combat oxidative stress and inflammatory processes in farm animals.

    Science.gov (United States)

    Gessner, D K; Ringseis, R; Eder, K

    2017-08-01

    Polyphenols are secondary plant metabolites which have been shown to exert antioxidative and antiinflamma tory effects in cell culture, rodent and human studies. Based on the fact that conditions of oxidative stress and inflammation are highly relevant in farm animals, polyphenols are considered as promising feed additives in the nutrition of farm animals. However, in contrast to many studies existing with model animals and humans, potential antioxidative and antiinflammatory effects of polyphenols have been less investigated in farm animals so far. This review aims to give an overview about potential antioxidative and antiinflammatory effects in farm animals. The first part of the review highlights the occurrence and the consequences of oxidative stress and inflammation on animal health and performance. The second part of the review deals with bioavailability and metabolism of polyphenols in farm animals. The third and main part of the review presents an overview of the findings from studies which investigated the effects of polyphenols of various plant sources in pigs, poultry and cattle, with particular consideration of effects on the antioxidant system and inflammation. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  5. Recycling as a strategy against rare earth element criticality: a systemic evaluation of the potential yield of NdFeB magnet recycling.

    Science.gov (United States)

    Rademaker, Jelle H; Kleijn, René; Yang, Yongxiang

    2013-09-17

    End-of-life recycling is promoted by OECD countries as a promising strategy in the current global supply crisis surrounding rare earth elements (REEs) so that dependence on China, the dominant supplier, can be decreased. So far the feasibility and potential yield of REE recycling has not been systematically evaluated. This paper estimates the annual waste flows of neodymium and dysprosium from permanent magnets, the main deployment of these critical REEs, during the 2011-2030 period. The estimates focus on three key permanent magnet waste flows: wind turbines, hybrid and electric vehicles, and hard disk drives (HDDs) in personal computers (PCs). This is a good indication of the end-of-life recycling of neodymium and dysprosium maximum potential yield. Results show that for some time to come, waste flows from permanent magnets will remain small relative to the rapidly growing global REE demand. Policymakers therefore need to be aware that during the next decade recycling is unlikely to substantially contribute to global REE supply security. In the long term, waste flows will increase sharply and will meet a substantial part of the total demand for these metals. Future REE recycling efforts should, therefore, focus on the development of recycling technology and infrastructure.

  6. Influence of anode material on the electrochemical oxidation of 2-naphthol Part 1. Cyclic voltammetry and potential step experiments

    Energy Technology Data Exchange (ETDEWEB)

    Panizza, M.; Cerisola, G

    2003-10-15

    The anodic oxidation of 2-naphthol has been studied by cyclic voltammetry and chronoamperometry, using a range of electrode materials such as Ti-Ru-Sn ternary oxide, lead dioxide and boron-doped diamond (BDD) anodes. The results show that polymeric films, which cause electrode fouling, are formed during oxidation in the potential region of supporting electrolyte stability. IR spectroscopy verified the formation of this organic film. While the Ti-Ru-Sn ternary oxide surface cannot be reactivated, PbO{sub 2} and BDD can be restored to their initial activity by simple anodic treatment in the potential region of electrolyte decomposition. In fact, during the polarization in this region, complex oxidation reactions leading to the complete incineration of polymeric materials can take place on these electrodes due to electrogenerated hydroxyl radicals. Moreover, it was found that BDD deactivation was less pronounced and its reactivation was faster than that of the other electrodes.

  7. Influence of anode material on the electrochemical oxidation of 2-naphthol Part 1. Cyclic voltammetry and potential step experiments

    International Nuclear Information System (INIS)

    Panizza, M.; Cerisola, G.

    2003-01-01

    The anodic oxidation of 2-naphthol has been studied by cyclic voltammetry and chronoamperometry, using a range of electrode materials such as Ti-Ru-Sn ternary oxide, lead dioxide and boron-doped diamond (BDD) anodes. The results show that polymeric films, which cause electrode fouling, are formed during oxidation in the potential region of supporting electrolyte stability. IR spectroscopy verified the formation of this organic film. While the Ti-Ru-Sn ternary oxide surface cannot be reactivated, PbO 2 and BDD can be restored to their initial activity by simple anodic treatment in the potential region of electrolyte decomposition. In fact, during the polarization in this region, complex oxidation reactions leading to the complete incineration of polymeric materials can take place on these electrodes due to electrogenerated hydroxyl radicals. Moreover, it was found that BDD deactivation was less pronounced and its reactivation was faster than that of the other electrodes

  8. Temporal patterning of the potential induced by localized corrosion of iron passivity in acid media. Growth and breakdown of the oxide film described in terms of a point defect model.

    Science.gov (United States)

    Sazou, Dimitra; Pavlidou, Maria; Pagitsas, Michael

    2009-10-21

    This work analyses the nature of temporal patterning of the anodic potential induced by chlorides during polarization of iron under current-controlled conditions in acid solutions. It is shown that potential oscillations emerged as a result of the local chloride attack of a thin oxide layer, which covers the iron surface in its passive state. The mechanism by which both the local oxide breakdown and the subsequent localized active dissolution (pitting) occur is explained by considering a point defect model (PDM) developed to describe the oxide growth and breakdown. According to the PDM, chlorides occupy oxygen vacancies resulting in the inhibition of oxide growth and autocatalytic generation of cation vacancies that destabilize the oxide layer. Simultaneous transformation of the outer surface of the inner oxide layer to non-adherent ferrous chloride or oxo-chloride species leads to a further thinning of the oxide layer and its lifting-on from the iron surface. The process repeats again yielding sustained oscillations of the anodic potential. Analysis of the oscillatory response obtained under current-controlled conditions as a function of either the current or the time allows the suggestion of a set of alternate diagnostic criteria, which might be used to characterize localized corrosion of iron in acid solutions.

  9. Oxidation of suspected N-nitrosodimethylamine (NDMA) precursors by ferrate (VI): kinetics and effect on the NDMA formation potential of natural waters.

    Science.gov (United States)

    Lee, Changha; Lee, Yunho; Schmidt, Carsten; Yoon, Jeyong; Von Gunten, Urs

    2008-01-01

    The potential of ferrate (Fe(VI)) oxidation to remove N-nitrosodimethylamine (NDMA) precursors during water treatment was assessed. Apparent second-order rate constants (k(app)) for the reactions of NDMA and its suspected precursors (dimethylamine (DMA) and 7 tertiary amines with DMA functional group) with Fe(VI) were determined in the range of pH 6-12. Four model NDMA precursors (dimethyldithiocarbamate, dimethylaminobenzene, 3-(dimethylaminomethyl)indole and 4-dimethylaminoantipyrine) showed high reactivity toward Fe(VI) with k(app) values at pH 7 between 2.6 x 10(2) and 3.2 x 10(5)M(-1)s(-1). The other NDMA precursors (DMA, trimethylamine, dimethylethanolamine, dimethylformamide) and NDMA had k(app) values ranging from 0.55 to 9.1M(-1)s(-1) at pH 7. In the second part of the study, the NDMA formation potentials (NDMA-FP) of the model NDMA precursors and natural waters were measured with and without pre-oxidation by Fe(VI). For most of the NDMA precursors with the exception of DMA, a significant reduction of the NDMA-FP (>95%) was observed after complete transformation of the NDMA precursor. This result was supported by low yields of DMA from the Fe(VI) oxidation of tertiary amine NDMA precursors. Pre-oxidation of several natural waters (rivers Rhine, Neckar and Pfinz) with a high dose of Fe(VI) (0.38 mM = 21 mg L(-1) as Fe) led to removals of the NDMA-FP of 46-84%. This indicates that the NDMA precursors in these waters have a low reactivity toward Fe(VI) because it has been shown that for fast-reacting NDMA precursors Fe(VI) doses of 20 microM (1.1 mg L(-1) as Fe) are sufficient to completely oxidize the precursors.

  10. The oxidative potential and biological effects induced by PM{sub 10} obtained in Mexico City and at a receptor site during the MILAGRO Campaign

    Energy Technology Data Exchange (ETDEWEB)

    Quintana, Raul [Instituto Nacional de Cancerologia, Mexico City (Mexico); Serrano, Jesus [Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, Mexico City (Mexico); Gomez, Virginia [Instituto de Quimica, Universidad Nacional Autonoma de Mexico, Mexico City (Mexico); Foy, Benjamin de [Earth and Atmospheric Sciences, Saint Louis University, St. Louis, MO (United States); Miranda, Javier [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Mexico City (Mexico); Garcia-Cuellar, Claudia [Instituto Nacional de Cancerologia, Mexico City (Mexico); Vega, Elizabeth [Instituto Mexicano del Petroleo, Mexico City (Mexico); Vazquez-Lopez, Ines [Instituto Nacional de Cancerologia, Mexico City (Mexico); Molina, Luisa T. [Molina Center for Energy and the Environment, CA (United States); Massachusetts Institute of Technology, Cambridge, MA (United States); Manzano-Leon, Natalia [Instituto Nacional de Cancerologia, Mexico City (Mexico); Rosas, Irma [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Mexico City (Mexico); Osornio-Vargas, Alvaro R., E-mail: osornio@ualberta.ca [Instituto Nacional de Cancerologia, Mexico City (Mexico); Department of Paediatrics, University of Alberta, 1048 RTF, 8308 114 St, Edmonton, AB T6G 2V2 (Canada)

    2011-12-15

    As part of a field campaign that studied the impact of Mexico City pollution plume at the local, sub-regional and regional levels, we studied transport-related changes in PM{sub 10} composition, oxidative potential and in vitro toxicological patterns (hemolysis, DNA degradation). We collected PM{sub 10} in Mexico City (T{sub 0}) and at a suburban-receptor site (T{sub 1}), pooled according to two observed ventilation patterns (T{sub 0} {yields} T{sub 1} influence and non-influence). T{sub 0} samples contained more Cu, Zn, and carbon whereas; T{sub 1} samples contained more of Al, Si, P, S, and K (p < 0.05). Only SO{sub 4}{sup -2} increased in T{sub 1} during the influence periods. Oxidative potential correlated with Cu/Zn content (r = 0.74; p < 0.05) but not with biological effects. T{sub 1} PM{sub 10} induced greater hemolysis and T{sub 0} PM{sub 10} induced greater DNA degradation. Influence/non-influence did not affect oxidative potential nor biological effects. Results indicate that ventilation patterns had little effect on intrinsic PM{sub 10} composition and toxicological potential, which suggests a significant involvement of local sources. - Highlights: > Transport-related changes in PM{sub 10} composition, oxidative potential and in vitro toxicity were studied. > Cu, Zn, and carbon levels were predominant in urban PM{sub 10}; receptor site PM{sub 10} was rich in soil elements. > SO{sub 4}{sup -2} was the only component increased in PM{sub 10} from the receptor during the influence periods. > PM{sub 10} oxidative potential correlates with Cu/Zn content but not with studied biological effects. > Ventilation patterns had little effect on PM{sub 10} composition and toxicity. - Mexico City ventilation patterns had little effect on the intrinsic PM{sub 10} composition and toxicological potential, which suggests a significant involvement of local sources as opposed to downwind transport.

  11. Solar-mediated thermo-electrochemical oxidation of sodium dodecyl benzene sulfonate by modulating the effective oxidation potential and pathway for green remediation of wastewater

    Science.gov (United States)

    Gu, Di; Gao, Simeng; Jiang, TingTing; Wang, Baohui

    2017-01-01

    To match the relentless pursuit of three research hot points - efficient solar utilization, green and sustainable remediation of wastewater and advanced oxidation processes, solar-mediated thermo-electrochemical oxidation of surfactant was proposed and developed for green remediation of surfactant wastewater. The solar thermal electrochemical process (STEP), fully driven with solar energy to electric energy and heat and without an input of other energy, sustainably serves as efficient thermo-electrochemical oxidation of surfactant, exemplified by SDBS, in wastewater with the synergistic production of hydrogen. The electrooxidation-resistant surfactant is thermo-electrochemically oxidized to CO2 while hydrogen gas is generated by lowing effective oxidation potential and suppressing the oxidation activation energy originated from the combination of thermochemical and electrochemical effect. A clear conclusion on the mechanism of SDBS degradation can be proposed and discussed based on the theoretical analysis of electrochemical potential by quantum chemical method and experimental analysis of the CV, TG, GC, FT-IR, UV-vis, Fluorescence spectra and TOC. The degradation data provide a pilot for the treatment of SDBS wastewater that appears to occur via desulfonation followed by aromatic-ring opening. The solar thermal utilization that can initiate the desulfonation and activation of SDBS becomes one key step in the degradation process. PMID:28294180

  12. Physical stability, biocompatibility and potential use of hybrid iron oxide-gold nanoparticles as drug carriers

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, Christopher M. [School of Pharmacy, Keele University (United Kingdom); Gueorguieva, Mariana [Institute of Medical Science and Technology, University of Dundee (United Kingdom); Lees, Martin R. [University of Warwick, Physics Department (United Kingdom); McGarvey, David J. [School of Physical and Geographical Sciences, Keele University, Lennard-Jones Laboratories (United Kingdom); Hoskins, Clare, E-mail: c.hoskins@keele.ac.uk [Institute for Science and Technology in Medicine, Keele University (United Kingdom)

    2013-06-15

    Hybrid nanoparticles (HNPs) such as iron oxide-gold nanoparticles are currently being exploited for their potential application in image-guided therapies. However, little investigation has been carried out into their physical or chemical stability and potential cytotoxicity in biological systems. Here, we determine the HNPs physical stability over 6 months and chemical stability in physiological conditions, and estimate the biological activity of uncoated and poly(ethylene glycol) coated nanoparticles on human pancreatic adenocarcinoma (BxPC-3) and differentiated human monocyte cells (U937). The potential of these HNPs to act as drug carrier vehicles was determined using the model drug 6-Thioguanine (6-TG). The data showed that the HNPs maintained their structural integrity both physically and chemically throughout the duration of the studies. In addition, negligible cytotoxicity or free radical production was observed in the cell lines tested. The 6-TG was successfully conjugated; with a ratio of 3:1:10 Fe:Au:6-TG (wt:wt:wt). After incubation with BxPC-3 cells, enhanced cellular uptake was reported with the 6-TG-conjugated HNPs compared with free drug along with a 10-fold decrease in IC{sub 50}. This exciting data highlights the potential of HNPs for use in image-guided drug delivery.

  13. The ignitability potential of uranium {open_quotes}roaster oxide{close_quotes}

    Energy Technology Data Exchange (ETDEWEB)

    Stakebake, J.L.

    1994-11-01

    The oxidation of uranium to form Uranium `roaster oxide` was investigated with respect to concerns of unreacted metal remaining in the roaster oxide matrix. It was found that ignition of unreacted uranium chips in the roaster oxide as synthesized is unlikely under normal storage conditions.

  14. Cholesterol oxidized products in foods: potential health hazards and the role of antioxidants in prevention

    Directory of Open Access Journals (Sweden)

    Nieto, Susana

    2004-09-01

    Full Text Available Cholesterol is a molecule with a double bond in its structure, and therefore it is susceptible to oxidation leading to the formation of oxysterols. These oxidation products are found in many commonly consumed foods and are formed during their manufacture and/or processing. Concern about the consumption of oxysterols arises from the potentially cytotoxic, mutagenic, atherogenic, and possibly carcinogenic effects of some of them. Eggs and egg-derived products are the main dietary sources of oxysterols. Thermally processed milk and milk-derived products are also another source of oxysterols in our diet. Fried meats, and other miscellaneous foods, such as French fried potatoes, when prepared using vegetable/animal frying oil, are another important source of oxysterols in the western diet. Efforts to prevent or to reduce cholesterol oxidation are directed to the application of antioxidants of either synthetic or natural origin. Antioxidants cannot only inhibit triglyceride oxidation, but some of them can also inhibit cholesterol oxidation. Among synthetic antioxidants, 2,6-di-ter tiarybutyl-4-methylphenol (BHT and ter tiary butylhydroquinone (TBHQ , can eff icient ly inhibit the thermal-induced oxidation of cholesterol. Among natural antioxidants, alpha- and gamma-tocopherol, rosemary extracts, and flavonoid quercetin, show the strongest inhibitory action against cholesterol oxidation.El colesterol es una molécula con un doble enlace en su estructura; por lo tanto es susceptible a la oxidación y su transformación en oxiesteroles. Estos productos de oxidación se encuentran en gran diversidad de alimentos y se forman durante la manufactura y procesamiento. Algunos de los oxiesteroles son potencialmente citotóxicos, mutagénicos, aterogénicos y carcinogénicos. Los huevos y productos derivados del huevo constituyen la principal fuente en la dieta de oxiesteroles. También se encuentran oxiesteroles en derivados lácteos y leche sometida a altas

  15. Biochemical leaf traits as indicators of tolerance potential in tree species from the Brazilian Atlantic Forest against oxidative environmental stressors.

    Science.gov (United States)

    Brandão, Solange E; Bulbovas, Patricia; Lima, Marcos E L; Domingos, Marisa

    2017-01-01

    The tolerance potential against the oxidative injury in native plants from forest ecosystems affected by environmental stressors depends on how efficiently they keep their pro-oxidant/antioxidant balance. Great variations in plant tolerance are expected, highlighting the higher relevance of measuring biochemical leaf trait indicators of oxidative injury in species with similar functions in the forest than in single species. The use of this functional approach seems very useful in the Brazilian Atlantic Forest because it still holds high plant diversity and was the focus of this study. We aimed at determining the tolerance potential of tree species from the Atlantic Forest remnants in SE Brazil against multiple oxidative environmental stressors. We assumed that pioneer tree species are more tolerant against oxidative stress than non-pioneer tree species and that their tolerance potential vary spatially in response to distinct combined effects of oxidative environmental stressors. The study was carried out in three Atlantic Forest remnants, which differ in physiognomy, species composition, climatic characteristics and air pollution exposure. Leaves of three pioneer and three non-pioneer species were collected from each forest remnant during wet (January 2015) and dry periods (June 2015), for analyses of non-enzymatic and enzymatic antioxidants and oxidative injury indicators. Both hypotheses were confirmed. The pioneer tree species displayed biochemical leaf traits (e.g. high levels of ascorbic acid, glutathione and carotenoids and lower lipid peroxidation) that indicate their higher potential tolerance against oxidative environmental stressors than non-pioneer species. The biochemical leaf traits of both successional groups of species varied between the forest remnants, in response to a linear combination of oxidative environmental stressors, from natural (relative humidity and temperature) and anthropogenic sources (ozone and nitrogen dioxide). Copyright © 2016

  16. Antioxidant Potential of ulva rigida c. Agardh Extract: Protection from Oxidative Stress Hypothyroidism

    Directory of Open Access Journals (Sweden)

    S. TAŞ

    2014-06-01

    Full Text Available The purpose of this study was to evaluate the effects of Ulva rigida C. Agardh, one of the green algae, on and antioxidative system in the propylthiouracil (PTU-induced hypothyroid rats. Thirty-two rats randomly divided into four groups: control (C, control+U. rigida extract (C+UR, hypothyroid (H and hypothyroid+U. rigida extract (H+UR. U. rigida (2% was administered in drinking water for 5 weeks after the induction of hypothyroidism. Hypothyroid rats were under oxidative stress as reflected by icreased plasma and tissue malondialdehyde (MDA levels. U. rigida reduced serum total cholesterol and,- triglyceride levels and plasma and heart skeletal muscle, liver and,- kidney tissue MDA levels in the H+UR group. Serum total cholesterol and tissues MDA levels were reduced in the C+UR group. Whole blood glutathione peroxidase and erythrocyte superoxide dismutase activities were increased in the H+UR and C+UR groups compared with those of te respective control groups. Paraoxonase and arylesterase activities were lower in the H group and U. rigida increased paraoxonase and arylesterase activities in C+UR and H+UR groups. We conclude that hypothyroidism is associated with oxidative stress and, U. rigida extract might have a potential use as a protective antioxidant agent in hypothroidism.

  17. Potential roles of anaerobic ammonium and methane oxidation in the nitrogen cycle of wetland ecosystems.

    Science.gov (United States)

    Zhu, Guibing; Jetten, Mike S M; Kuschk, Peter; Ettwig, Katharina F; Yin, Chengqing

    2010-04-01

    Anaerobic ammonium oxidation (anammox) and anaerobic methane oxidation (ANME coupled to denitrification) with nitrite as electron acceptor are two of the most recent discoveries in the microbial nitrogen cycle. Currently the anammox process has been relatively well investigated in a number of natural and man-made ecosystems, while ANME coupled to denitrification has only been observed in a limited number of freshwater ecosystems. The ubiquitous presence of anammox bacteria in marine ecosystems has changed our knowledge of the global nitrogen cycle. Up to 50% of N(2) production in marine sediments and oxygen-depleted zones may be attributed to anammox bacteria. However, there are only few indications of anammox in natural and constructed freshwater wetlands. In this paper, the potential role of anammox and denitrifying methanotrophic bacteria in natural and artificial wetlands is discussed in relation to global warming. The focus of the review is to explore and analyze if suitable environmental conditions exist for anammox and denitrifying methanotrophic bacteria in nitrogen-rich freshwater wetlands.

  18. Galvanic Corrosion of Lead by Iron (Oxyhydr)Oxides: Potential Impacts on Drinking Water Quality.

    Science.gov (United States)

    Trueman, Benjamin F; Sweet, Gregory A; Harding, Matthew D; Estabrook, Hayden; Bishop, D Paul; Gagnon, Graham A

    2017-06-20

    Lead exposure via drinking water remains a significant public health risk; this study explored the potential effects of upstream iron corrosion on lead mobility in water distribution systems. Specifically, galvanic corrosion of lead by iron (oxyhydr)oxides was investigated. Coupling an iron mineral cathode with metallic lead in a galvanic cell increased lead release by 531 μg L -1 on average-a 9-fold increase over uniform corrosion in the absence of iron. Cathodes were composed of spark plasma sintered Fe 3 O 4 or α-Fe 2 O 3 or field-extracted Fe 3 O 4 and α-FeOOH. Orthophosphate immobilized oxidized lead as insoluble hydroxypyromorphite, while humic acid enhanced lead mobility. Addition of a humic isolate increased lead release due to uniform corrosion by 81 μg L -1 and-upon coupling lead to a mineral cathode-release due to galvanic corrosion by 990 μg L -1 . Elevated lead in the presence of humic acid appeared to be driven by complexation, with 208 Pb and UV 254 size-exclusion chromatograms exhibiting strong correlation under these conditions (R 2 average = 0.87). A significant iron corrosion effect was consistent with field data: lead levels after lead service line replacement were greater by factors of 2.3-4.7 at sites supplied by unlined cast iron distribution mains compared with the alternative, lined ductile iron.

  19. Evaluation of the Potential of Brazilian Propolis against UV-Induced Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Yris Maria Fonseca

    2011-01-01

    Full Text Available This study investigated the potential use of topically and orally administered propolis extracts to prevent UV irradiation-induced oxidative stress in skin. The results illustrated that green propolis extract (GPE contained greater amounts of polyphenols, coumaric acid, drupanin, baccharin and artepillin C than did brown propolis extract (BPE. GPE showed higher antioxidant activity than BPE when the IC50 (concentration that caused 50% inhibition values were compared. Interesting, the oral treatment of hairless mice demonstrated a recovery of 30.0% for GPE and 22.8% for BPE with respect to UV irradiation-induced GSH depletion. The topical pretreatment of animals with both propolis extract solutions recovered around 14.0% of the depleted GSH. However, the employed treatments did not inhibit the increase of cutaneous proteinase secretion/activity caused by irradiation. These findings indicate that despite differences in composition and antioxidant properties, GPE and BPE both successfully prevent UV-induced GSH depletion in vivo and are both promising antioxidant systems against oxidative stress in skin. Based on these findings, complementary studies should be performed to enhance our understanding of the protective effects of propolis extracts in skin.

  20. Collagen type I from bovine bone. Effect of animal age, bone anatomy and drying methodology on extraction yield, self-assembly, thermal behaviour and electrokinetic potential.

    Science.gov (United States)

    Ferraro, Vincenza; Gaillard-Martinie, Brigitte; Sayd, Thierry; Chambon, Christophe; Anton, Marc; Santé-Lhoutellier, Véronique

    2017-04-01

    Natural collagen is easily available from animal tissues such as bones. Main limitations reported in the use of natural collagen are heterogeneity and loss of integrity during recovery. However, its natural complexity, functionality and bioactivity still remain to be achieved through synthetic and recombinant ways. Variability of physicochemical properties of collagen extracted from bovine bone by acetic acid was then investigated taking into account endogenous and exogenous factors. Endogenous: bovine's bones age (4 and 7 years) and anatomy (femur and tibia); exogenous: thermal treatments (spray-drying and lyophilisation). Scanning electron microscopy, spectroscopy (EDS, FTIR, UV/Vis and CD), differential scanning calorimetry (DSC), centesimal composition, mass spectrometry, amino acids and zeta-potential analysis were used for the purpose. Age correlated negatively with yield of recovery and positively with minerals and proteoglycans content. Comparing the anatomy, higher yields were found for tibias, and higher stability of tibias collagen in solution was noticed. Whatever the age and the anatomy, collagens were able to renature and to self-assemble into tri-dimensional structures. Nonetheless thermal stability and kinetics of renaturation were different. Variability of natural collagen with bone age and anatomy, and drying methodology, may be a crucial advantage to conceive tailor-made applications in either the biological or technical sector. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Biomass yielding potential of naturally regenerated Prosopis juliflora tree stands at three varied ecosystems in southern districts of Tamil Nadu, India.

    Science.gov (United States)

    Saraswathi, K; Chandrasekaran, S

    2016-05-01

    Fuel energy demand is of great concern in recent times due to the depletion of fossil fuel resources. Biomass serves as widely available primary renewable energy source. Hence, a study was performed to assess the above-ground biomass yielding capability of fuel wood tree Prosopis juliflora in three varied ecosystems viz., coastal, fallow land and riparian ecosystems in southern districts of Tamil Nadu. The results showed that the biomass production potential and above-ground net primary productivity of P. juliflora depend on the age of the tree stands and the nature of ecosystem. A higher biomass yield was observed for P. juliflora trees with 5 to 10 years old when compared to less than 5 years of their age. Among the three ecosystems, the maximum biomass production was recorded in riparian ecosystem. The stands with less than 5-year-old P. juliflora trees gave 1.40 t/ha, and 5- to 10-year-old tree stands produced 27.69 t/ha in riparian ecosystem. Above-ground net primary productivity of both the age groups was high in fallow land ecosystem. In riparian ecosystem, the wood showed high density and low sulphur content than the other two ecosystems. Hence, P. juliflora biomass can serve as an environmentally and economically feasible fuel as well as their utilization proffers an effective means to control its invasiveness.

  2. Investigation of surface potentials in reduced graphene oxide flake by Kelvin probe force microscopy

    Science.gov (United States)

    Negishi, Ryota; Takashima, Kai; Kobayashi, Yoshihiro

    2018-06-01

    The surface potential (SP) of reduced graphene oxide (rGO) flakes prepared by thermal treatments of GO under several conditions was analyzed by Kelvin probe force microscopy. The low-crystalline rGO flakes in which a significant amount of oxygen functional groups and structural defects remain have a much lower SP than mechanically exfoliated graphene free from oxygen and defects. On the other hand, the highly crystalline rGO flake after a thermal treatment for the efficient removal of oxygen functional groups and healing of structural defects except for domain boundary shows SP equivalent to that of the mechanically exfoliated graphene. These results indicate that the work function of rGO is sensitively modulated by oxygen functional groups and structural defects remaining after the thermal reduction process, but is not affected significantly by the domain boundary remaining after the healing of structural defects through the thermal treatment at high temperature.

  3. The potential of large critical currents in the high Tc oxides

    International Nuclear Information System (INIS)

    Deutcher, G.

    1993-01-01

    The potential for high critical current densities is examined. on a thermodynamical basis, the energy scale for vortex pinning can be derived for instance from a measurement of the width of the critical region. This energy scale is of the order of 0.2 eV in YBCO, which is sufficient for practical applications. Another important parameter is the short coherence length. The inner plane length, of the order of a few lattice spacing, is favorable for pinning by point defects. But the very short outer plane length gives rise to anomalous magnetic behavior, unfavorable for high-field applications at high temperature; this is true in particular in most anisotropic oxides, such as the Bi compounds (author)

  4. In vitro oxidative stress regulatory potential of Citrullus colocynthis and Tephrosia apollinea

    Directory of Open Access Journals (Sweden)

    Rizvi Tania Shamim

    2018-06-01

    Full Text Available The present study investigates the potential role of medicinal plants Citrullus colocynthis and Tephrosia apollinea in ameliorating the oxidative stress developed during the generation of reactive oxygen species. Organic extracts of different organs (leaf, stem and root of these medicinal plants obtained in n-hexane, chloroform, n-butanol and water were assayed for radical scavenging, total antioxidant capacity, anti-lipid peroxidation and reduced glutathione. The total phenolic content (TPC of both selected medicinal plants was also evaluated. The results indicated that extracts of T. apollinea leaf, stem and root have higher TPC compared to those of C. colocynthis. Similarly, the results of the present study revealed higher bioactivity of C. colocynthis than that of T. apollinea in various antioxidant assays. Various plant parts of each plant were also compared.

  5. Oxygen Distribution and Potential Ammonia Oxidation in Floating, Liquid Manure Crusts

    DEFF Research Database (Denmark)

    Nielsen, Daniel Aagren; Nielsen, Lars Peter; Schramm, Andreas

    2010-01-01

    Floating, organic crusts on liquid manure, stored as a result of animal production, reduce emission of ammonia (NH3) and other volatile compounds during storage. The occurrence of NO2- and NO3- in the crusts indicate the presence of actively metabolizing NH3 oxidizing bacteria (AOB) which may...... be partly responsible for this mitigation effect. Six manure tanks with organic covers (straw and natural) were surveyed to investigate the prevalence and potential activity of AOB and its dependence on the O2 availability in the crust matrix as studied by electrochemical profiling. Oxygen penetration...... microorganisms, including AOB. The microbial activity may thus contribute to a considerable reduction of ammonia emissions from slurry tanks with well-developed crusts....

  6. Zinc oxide nanoparticles mediated cytotoxicity, mitochondrial membrane potential and level of antioxidants in presence of melatonin.

    Science.gov (United States)

    Sruthi, S; Millot, N; Mohanan, P V

    2017-10-01

    Zinc oxide nanoparticles (ZnO NPs) are widely used in a variety of products and are currently being investigated for biomedical applications. However, they have the potential to interact with macromolecules like proteins, lipids and DNA within the cells which makes the safe biomedical application difficult. The toxicity of the ZnO NP is mainly attributed reactive oxygen species (ROS) generation. Different strategies like iron doping, polymer coating and external supply of antioxidants have been evaluated to minimize the toxic potential of ZnO NPs. Melatonin is a hormone secreted by the pineal gland with great antioxidant properties. The melatonin is known to protect cells from ROS inducing external agents like lipopolysaccharides. In the present study, the protective effect of melatonin on ZnO NPs mediated toxicity was evaluated using C6 glial cells. The Cytotoxicity, mitochondrial membrane potential and free radical formation were measured to study the effect of melatonin. Antioxidant assays were done on mice brain slices, incubated with melatonin and ZnO NPs. The results of the study reveal that, instead of imparting a protective effect, the melatonin pre-treatment enhanced the toxicity of ZnO NPs. Melatonin increased antioxidant enzymes in brain slices. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Biological versus mineralogical chromium reduction: potential for reoxidation by manganese oxide.

    Science.gov (United States)

    Butler, Elizabeth C; Chen, Lixia; Hansel, Colleen M; Krumholz, Lee R; Elwood Madden, Andrew S; Lan, Ying

    2015-11-01

    Hexavalent chromium (Cr(vi), present predominantly as CrO4(2-) in water at neutral pH) is a common ground water pollutant, and reductive immobilization is a frequent remediation alternative. The Cr(iii) that forms upon microbial or abiotic reduction often co-precipitates with naturally present or added iron (Fe), and the stability of the resulting Fe-Cr precipitate is a function of its mineral properties. In this study, Fe-Cr solids were formed by microbial Cr(vi) reduction using Desulfovibrio vulgaris strain RCH1 in the presence of the Fe-bearing minerals hematite, aluminum substituted goethite (Al-goethite), and nontronite (NAu-2, Clay Minerals Society), or by abiotic Cr(vi) reduction by dithionite reduced NAu-2 or iron sulfide (FeS). The properties of the resulting Fe-Cr solids and their behavior upon exposure to the oxidant manganese (Mn) oxide (birnessite) differed significantly. In microcosms containing strain RCH1 and hematite or Al-goethite, there was significant initial loss of Cr(vi) in a pattern consistent with adsorption, and significant Cr(vi) was found in the resulting solids. The solid formed when Cr(vi) was reduced by FeS contained a high proportion of Cr(iii) and was poorly crystalline. In microcosms with strain RCH1 and hematite, Cr precipitates appeared to be concentrated in organic biofilms. Reaction between birnessite and the abiotically formed Cr(iii) solids led to production of significant dissolved Cr(vi) compared to the no-birnessite controls. This pattern was not observed in the solids generated by microbial Cr(vi) reduction, possibly due to re-reduction of any Cr(vi) generated upon oxidation by birnessite by active bacteria or microbial enzymes. The results of this study suggest that Fe-Cr precipitates formed in groundwater remediation may remain stable only in the presence of active anaerobic microbial reduction. If exposed to environmentally common Mn oxides such as birnessite in the absence of microbial activity, there is the potential

  8. Chronic lead exposure induces cochlear oxidative stress and potentiates noise-induced hearing loss.

    Science.gov (United States)

    Jamesdaniel, Samson; Rosati, Rita; Westrick, Judy; Ruden, Douglas M

    2018-08-01

    Acquired hearing loss is caused by complex interactions of multiple environmental risk factors, such as elevated levels of lead and noise, which are prevalent in urban communities. This study delineates the mechanism underlying lead-induced auditory dysfunction and its potential interaction with noise exposure. Young-adult C57BL/6 mice were exposed to: 1) control conditions; 2) 2 mM lead acetate in drinking water for 28 days; 3) 90 dB broadband noise 2 h/day for two weeks; and 4) both lead and noise. Blood lead levels were measured by inductively coupled plasma mass spectrometry analysis (ICP-MS) lead-induced cochlear oxidative stress signaling was assessed using targeted gene arrays, and the hearing thresholds were assessed by recording auditory brainstem responses. Chronic lead exposure downregulated cochlear Sod1, Gpx1, and Gstk1, which encode critical antioxidant enzymes, and upregulated ApoE, Hspa1a, Ercc2, Prnp, Ccl5, and Sqstm1, which are indicative of cellular apoptosis. Isolated exposure to lead or noise induced 8-12 dB and 11-25 dB shifts in hearing thresholds, respectively. Combined exposure induced 18-30 dB shifts, which was significantly higher than that observed with isolated exposures. This study suggests that chronic exposure to lead induces cochlear oxidative stress and potentiates noise-induced hearing impairment, possibly through parallel pathways. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Potential of Genomic Selection in Mass Selection Breeding of an Allogamous Crop: An Empirical Study to Increase Yield of Common Buckwheat

    Directory of Open Access Journals (Sweden)

    Shiori Yabe

    2018-03-01

    Full Text Available To evaluate the potential of genomic selection (GS, a selection experiment with GS and phenotypic selection (PS was performed in an allogamous crop, common buckwheat (Fagopyrum esculentum Moench. To indirectly select for seed yield per unit area, which cannot be measured on a single-plant basis, a selection index was constructed from seven agro-morphological traits measurable on a single plant basis. Over 3 years, we performed two GS and one PS cycles per year for improvement in the selection index. In GS, a prediction model was updated every year on the basis of genotypes of 14,598–50,000 markers and phenotypes. Plants grown from seeds derived from a series of generations of GS and PS populations were evaluated for the traits in the selection index and other yield-related traits. GS resulted in a 20.9% increase and PS in a 15.0% increase in the selection index in comparison with the initial population. Although the level of linkage disequilibrium in the breeding population was low, the target trait was improved with GS. Traits with higher weights in the selection index were improved more than those with lower weights, especially when prediction accuracy was high. No trait changed in an unintended direction in either GS or PS. The accuracy of genomic prediction models built in the first cycle decreased in the later cycles because the genetic bottleneck through the selection cycles changed linkage disequilibrium patterns in the breeding population. The present study emphasizes the importance of updating models in GS and demonstrates the potential of GS in mass selection of allogamous crop species, and provided a pilot example of successful application of GS to plant breeding.

  10. Potential of Genomic Selection in Mass Selection Breeding of an Allogamous Crop: An Empirical Study to Increase Yield of Common Buckwheat.

    Science.gov (United States)

    Yabe, Shiori; Hara, Takashi; Ueno, Mariko; Enoki, Hiroyuki; Kimura, Tatsuro; Nishimura, Satoru; Yasui, Yasuo; Ohsawa, Ryo; Iwata, Hiroyoshi

    2018-01-01

    To evaluate the potential of genomic selection (GS), a selection experiment with GS and phenotypic selection (PS) was performed in an allogamous crop, common buckwheat ( Fagopyrum esculentum Moench). To indirectly select for seed yield per unit area, which cannot be measured on a single-plant basis, a selection index was constructed from seven agro-morphological traits measurable on a single plant basis. Over 3 years, we performed two GS and one PS cycles per year for improvement in the selection index. In GS, a prediction model was updated every year on the basis of genotypes of 14,598-50,000 markers and phenotypes. Plants grown from seeds derived from a series of generations of GS and PS populations were evaluated for the traits in the selection index and other yield-related traits. GS resulted in a 20.9% increase and PS in a 15.0% increase in the selection index in comparison with the initial population. Although the level of linkage disequilibrium in the breeding population was low, the target trait was improved with GS. Traits with higher weights in the selection index were improved more than those with lower weights, especially when prediction accuracy was high. No trait changed in an unintended direction in either GS or PS. The accuracy of genomic prediction models built in the first cycle decreased in the later cycles because the genetic bottleneck through the selection cycles changed linkage disequilibrium patterns in the breeding population. The present study emphasizes the importance of updating models in GS and demonstrates the potential of GS in mass selection of allogamous crop species, and provided a pilot example of successful application of GS to plant breeding.

  11. A direct current potential drop method for evaluating oxide film thickness formed in high-temperature water

    International Nuclear Information System (INIS)

    Anzai, Hideya; Ishibashi, Ryo; Saka, Masumi

    2016-01-01

    To establish an evaluation technique for oxide film thickness in-situ, the applicability of a four-point-probe direct current potential drop method is discussed in this study. Several samples of JIS SUS316L stainless steel with different oxide film thickness were prepared after immersing them in oxygenated pure water at 288°C for different periods. The oxide film thickness was measured by cross sectional observation using a transmission electron microscope. Potential drop on the oxide surface was measured every second during an acquisition period of about 20 s while a constant current was being injected into the sample simultaneously. This kind of measurement was repeatedly carried out at several arbitrary contact positions on the surface of the same sample. The measurement results showed that the potential drop slightly changed during the acquisition period and the tendency varied at the different contact positions. Multiple measurements at different contact positions revealed that the tendency could be categorized into two general types: the decreasing potential drop and the increasing potential drop, defined by the overall trend of the potential drop during the acquisition time. It was found that the ratio of contact positions with a decreasing potential drop tendency to all the contact positions of measurement tended to increase as applied current increased. This tendency depended on the oxide film thickness. The threshold value of applied current was found to correlate well with the oxide film thickness when the occurrence rate of decreasing potential drop ranged from 70 to 90% showing the best correlation at 70%. (author)

  12. Evaluation of liquid-phase oxidation for the destruction of potential chemical terrorism agents

    Energy Technology Data Exchange (ETDEWEB)

    Thouin, G.; Harrison, S.; Li, K.; Kuang, W.; Volchek, K.; Fingas, M. [Environment Canada, Ottawa, ON (Canada). Emergencies Science Div; Potaraju, S.; Velicogna, D.; Obenauf, A. [SAIC Canada, Ottawa, ON (Canada)

    2005-07-01

    Although pesticides are designed to protect crops and livestock against insects, fungi or nuisance plants, the toxicity of these compounds is not limited to target species. Organophosphorus, organochlorine and carbamate pesticides all target the nervous systems of insects. This paper assessed the effectiveness of an enhanced oxidation process using peroxycarboxylic acids for the liquid-phase destruction of toxic industrial chemicals, considered to be potential agents of chemical terrorism. Peroxyacetic acid (PAA) and peroxypropionic acid (PPA) were tested as decontamination agents on organophosphorus, organochlorine and carbamate pesticides. The processes were reviewed in relation to the terms of percent agent destruction over time, with a target of 90 per cent destruction within 30 minutes. Effectiveness was also assessed on the accumulation of toxic by-products. A background of the pesticides was presented, as well as details of their various applications. The molecular structures of the compounds were also provided. Oxidation extraction procedures, materials and methods were also presented, as well as analytical techniques, method detection limits and issues concerning reproducibility. The pH profile of PAA and PPA as a function of the concentration in acid was studied in order to determine which was more likely to be corrosive. It was concluded that peroxycarboxylic acids are effective decontamination agents for organophosphorous and carbamate pesticides. PAA and PPA are equally effective in degrading the examined pesticides, however, greater amounts of toxic by-products are found with PPA than with PAA. Neither PAA nor PPA were able to degrade lindane, and more lindane was found in the treated samples than in the controls. It was noted that time profiles for lower concentrations of peroxycarboxylic acids and pH profiles are currently being developed. It was suggested that further research in this area included degradation experiments on various types of

  13. Potential denitrification and nitrous oxide production in the sediments of the Seine River Drainage Network (France).

    Science.gov (United States)

    Garnier, Josette A; Mounier, Emmanuelle M; Laverman, Anniet M; Billen, Gilles F

    2010-01-01

    To investigate bottom sediment denitrification at the scale of the Seine drainage network, a semi-potential denitrification assay was used in which river sediments (and riparian soils) were incubated for a few hours under anaerobic conditions with non limiting nitrate concentrations. This method allowed the nitrous oxide (N(2)O) concentration in the headspace, as well as the nitrate, nitrite, and ammonium concentrations to be determined during incubation. The rates at which nitrate decreased and N(2)O increased were then used to assess the potential denitrification activity and associated N(2)O production in the Seine River Basin. We observed a longitudinal pattern characterized by a significant increase of the potential rate of denitrification from upstream sectors to large downstream rivers (orders 7-8), from approximately 3.3 to 9.1 microg NO(3)(-)-N g(-1) h(-1), respectively, while the N(2)O production rates was the highest both in headwaters and in large order rivers (0.14 and 0.09 N(2)O-N g(-1) h(-1), respectively) and significantly lower in the intermediate sectors (0.01 and 0.03 N(2)O-N g(-1) h(-1)). Consequently, the ratio N(2)O production:NO(3) reduction was found to reach 5% in headstreams, whereas it averaged 1.2% in the rest of the drainage network, an intermediate percentage being found for the riparian soils. Finally, the ignition loss of sediments, together with other redundant variables (particulate organic carbon content: g C 100 g(-1) dry weight [dw], moisture: g water 100 g(-1) dw, sediment size production.

  14. Biochar and flyash inoculated with plant growth promoting rhizobacteria act as potential biofertilizer for luxuriant growth and yield of tomato plant.

    Science.gov (United States)

    Tripti; Kumar, Adarsh; Usmani, Zeba; Kumar, Vipin; Anshumali

    2017-04-01

    Overuse of agrochemical fertilizers alarmingly causes deterioration in soil health and soil-flora. Persistence of these agrochemicals exerts detrimental effects on environment, potentially inducing toxic effects on human health, thus pronouncing an urgent need for a safer substitute. The present study investigates the potential use of agricultural and industrial wastes as carrier materials, viz. biochar and flyash, respectively, for preparation of bioformulations (or biofertilizers) using two plant growth promoting rhizobacteria, Bacillus sp. strain A30 and Burkholderia sp. strain L2, and its effect on growth of Lycopersicon esculentum Mill. (tomato). The viability of strains was determined based on colony forming units (cfu) count of each bioformulation at an interval of 60 days for a period of 240 days. Seeds were coated with different carrier based bioformulations and pot experiment(s) were carried out to access its effects on plant growth parameters. Biochar based bioformulations showed higher cfu count and maximum viability for strain L2 (10 7  cfu g -1 ) at 240 days of storage. Maximum percentage of seed germination was also observed in biochar inoculated with strain L2. Significant (p < 0.05) increase in plant growth parameters (dry and fresh biomass, length, number of flowers) were ascertained from the pot experiment and amongst all bioformulations, biochar inoculated with strain L2 performed consistently thriving results for tomato yield. Furthermore, post-harvest study of this bioformulation treated soil improved physico-chemical properties and dehydrogenase activity as compared to pre-plantation soil status. Overall, we show that prepared biochar based bioformulation using Burkholderia sp. L2 as inoculum can tremendously enhance the productivity of tomato, soil fertility, and can also act as a sustainable substitute for chemical fertilizers. In addition, mixture of biochar and flyash inoculated with strain L2 also showed noteworthy results for the

  15. Identification of Potential Metabolic Markers for the Selection of a High-Yield Clone of Quercus acutissima in Clonal Seed Orchard

    Directory of Open Access Journals (Sweden)

    Jun Won Kang

    2018-03-01

    Full Text Available Quercus acutissima Carruth. is one of the most economically important deciduous tree species in Korea. The acorns of Q. acutissima are used for both food and medicinal purposes in Korea and China. In this study, we analyzed plant hormones and metabolite profiles to identify their correlation with the yield production of Q. acutissima. The contents of sucrose and inositol in the leaves of high-yield clones were significantly higher (p < 0.05 than those of low-yield clones. In addition, high-yield clones have a higher content of phosphoric acid, succinic acid, malic acid, and butane-1,3-diol in stems compared with low-yield clones. Among the identified metabolites, zeatin-9-glucoside showed highly significant negative correlations with tree height, crown volume, and acorn production. It is considered that these metabolites could be useful metabolic markers for the selection of a high yield clone of Q. acutissima.

  16. YC-1 potentiates cAMP-induced CREB activation and nitric oxide production in alveolar macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Tsong-Long, E-mail: htl@mail.cgu.edu.tw [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China); Chinese Herbal Medicine Research Team, Healthy Aging Research Center, Chang Gung University, Kweishan, Taoyuan, Taiwan (China); Tang, Ming-Chi [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China); Kuo, Liang-Mou [Department of General Surgery, Chang Gung Memorial Hospital at Chia-Yi, Taiwan (China); Chang, Wen-De; Chung, Pei-Jen; Chang, Ya-Wen; Fang, Yao-Ching [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China)

    2012-04-15

    Alveolar macrophages play significant roles in the pathogenesis of several inflammatory lung diseases. Increases in exhaled nitric oxide (NO) are well documented to reflect disease severity in the airway. In this study, we investigated the effect of 3-(5′-hydroxymethyl-2′-furyl)-1-benzyl indazole (YC-1), a known activator of soluble guanylyl cyclase, on prostaglandin (PG)E{sub 1} (a stable PGE{sub 2} analogue) and forskolin (a adenylate cyclase activator) induced NO production and inducible NO synthase (iNOS) expression in rat alveolar macrophages (NR8383). YC-1 did not directly cause NO production or iNOS expression, but drastically potentiated PGE{sub 1}- or forskolin-induced NO production and iNOS expression in NR8383 alveolar macrophages. Combination treatment with YC-1 and PGE{sub 1} significantly increased phosphorylation of the cAMP response element-binding protein (CREB), but not nuclear factor (NF)-κB activation. The combined effect on NO production, iNOS expression, and CREB phosphorylation was reversed by a protein kinase (PK)A inhibitor (H89), suggesting that the potentiating functions were mediated through a cAMP/PKA signaling pathway. Consistent with this, cAMP analogues, but not the cGMP analogue, caused NO release, iNOS expression, and CREB activation. YC-1 treatment induced an increase in PGE{sub 1}-induced cAMP formation, which occurred through the inhibition of cAMP-specific phosphodiesterase (PDE) activity. Furthermore, the combination of rolipram (an inhibitor of PDE4), but not milronone (an inhibitor of PDE3), and PGE{sub 1} also triggered NO production and iNOS expression. In summary, YC-1 potentiates PGE{sub 1}-induced NO production and iNOS expression in alveolar macrophages through inhibition of cAMP PDE activity and activation of the cAMP/PKA/CREB signaling pathway. Highlights: ► YC-1 potentiated PGE1-induced iNOS expression in alveolar macrophages. ► The combination of YC-1 and PGE1 increased CREB but not NFκB activation.

  17. Modified crop model estimation of depleted and potential soybean yield=Modelo modificado de estimação da produtividade deplecionada e potencial da soja

    Directory of Open Access Journals (Sweden)

    Paulo Augusto Manfron

    2012-10-01

    Full Text Available Despite the great importance of soybeans in Brazil, there have been few applications of soybean crop modeling on Brazilian conditions. Thus, the objective of this study was to use modified crop models to estimate the depleted and potential soybean crop yield in Brazil. The climatic variable data used in the modified simulation of the soybean crop models were temperature, insolation and rainfall. The data set was taken from 33 counties (28 Sao Paulo state counties, and 5 counties from other states that neighbor São Paulo. Among the models, modifications in the estimation of the leaf area of the soybean crop, which includes corrections for the temperature, shading, senescence, CO2, and biomass partition were proposed; also, the methods of input for the model’s simulation of the climatic variables were reconsidered. The depleted yields were estimated through a water balance, from which the depletion coefficient was estimated. It can be concluded that the adaptation soybean growth crop model might be used to predict the results of the depleted and potential yield of soybeans, and it can also be used to indicate better locations and periods of tillage.Aplicações de modelos de previsão de produtividade na cultura da soja são muito raros. Assim, o objetivo desta pesquisa foi realizar a estimação da produtividade deplecionada e potencial da cultura de soja, usando modelos de previsão modificados. Os dados climáticos utilizados nos modelos de simulação foram a temperatura, precipitação e insolação. Os dados foram proveniente de 33 municípios (28 do estado de São Paulo, e cinco municípios de estados vizinhos. Dentre os modelos propostos modificados está a estimação da área foliar da soja, com correções para temperatura, sombreamento, senescência, CO2, partição de biomassa, bem como os métodos de simulação das variávies climáticas do “input” para o modelo. As produções deplecionadas foram estimadas através do balan

  18. The potential for biologically catalyzed anaerobic methane oxidation on ancient Mars.

    Science.gov (United States)

    Marlow, Jeffrey J; Larowe, Douglas E; Ehlmann, Bethany L; Amend, Jan P; Orphan, Victoria J

    2014-04-01

    This study examines the potential for the biologically mediated anaerobic oxidation of methane (AOM) coupled to sulfate reduction on ancient Mars. Seven distinct fluids representative of putative martian groundwater were used to calculate Gibbs energy values in the presence of dissolved methane under a range of atmospheric CO2 partial pressures. In all scenarios, AOM is exergonic, ranging from -31 to -135 kJ/mol CH4. A reaction transport model was constructed to examine how environmentally relevant parameters such as advection velocity, reactant concentrations, and biomass production rate affect the spatial and temporal dependences of AOM reaction rates. Two geologically supported models for ancient martian AOM are presented: a sulfate-rich groundwater with methane produced from serpentinization by-products, and acid-sulfate fluids with methane from basalt alteration. The simulations presented in this study indicate that AOM could have been a feasible metabolism on ancient Mars, and fossil or isotopic evidence of this metabolic pathway may persist beneath the surface and in surface exposures of eroded ancient terrains.

  19. Multifunctional carbon-coated magnetic sensing graphene oxide-cyclodextrin nanohybrid for potential cancer theranosis

    Science.gov (United States)

    Hsu, Yu-Hsuan; Hsieh, Hui-Ling; Viswanathan, Geetha; Voon, Siew Hui; Kue, Chin Siang; Saw, Wen Shang; Yeong, Chai Hong; Azlan, Che Ahmad; Imae, Toyoko; Kiew, Lik Voon; Lee, Hong Boon; Chung, Lip Yong

    2017-11-01

    We functionalized graphene oxide (GO) with cyclodextrin (CD) to increase the drug loading and cellular uptake of GO, and bound the GO-CD to carbon-coated iron nanoparticles (Fe@C) with superparamagnetic properties for potential magnetic-directed drug delivery and as a diagnostic agent. The GO-CD/Fe@C was loaded with an anticancer drug, doxorubicin (DOX), to form a multifunctional GO-CD/Fe@C/DOX nanohybrid. A cumulative increase in DOX loading was observed probably due to DOX adsorption to the graphitic domains in Fe@C and also to the GO-CD. In acidic pH that resembles the pH of the tumor environment, a higher amount of DOX was released from the GO-CD/Fe@C/DOX nanohybrid when compared to the amount released at physiological pH. The signal intensity and the contrast enhancement in magnetic resonance imaging of Fe@C decreased with its concentration. Besides, the cellular uptake of GO-CD/Fe@C/DOX nanohybrid was significantly higher by 2.5-fold than that of Fe@C/DOX in MDA-MB-231 human breast cancer model. The nanohybrids were internalized into the tumor cells via an energy-dependent process and localized mainly in the nuclei, where it exerts its cytotoxic effect, and some in the lysosomes and mitochondria. This has resulted in significant cytotoxicity in tumor cells treated with GO-CD/Fe@C/DOX. These findings highlight the potential use of multifunctional GO-CD/Fe@C nanohybrid for magnetic sensing anticancer drug delivery to tumor cells. [Figure not available: see fulltext.

  20. The controlled-potential coulometric determination of plutonium based upon cerium oxidation and the Pu022+/Pu4+ valency change

    International Nuclear Information System (INIS)

    Phillips, G.; Crossley, D.; Venkataramana, P.

    1977-09-01

    Conditions have been established enabling plutonium to be oxidised quantitatively to the hexavalent state in the working compartment of a controlled-potential coulometric cell using electrogenerated ceric ion or excess ceric nitrate. The excess ceric ion is reduced in situ electrochemically without reduction of the hexavalent plutonium. The plutonium is then determined controlled-potential coulometrically by reduction to Pu 3+ followed by oxidation to Pu 4+ . The first oxidation step is conducted in molar nitric acid solution containing sulphamic acid but the coulometric determination step is conducted in molar sulphuric acid solution. The results obtained in the coulometric determination step were less satisfactory following oxidation with electrogenerated ceric ion rather than with chemically added ceric nitrate. Using the recommended conditions, 6 mg quantities of plutonium can be determined with an accuracy of 100.06% and a precision of 0.12% (coefficient of variation). The behaviour of chromium, manganese and vanadium impurity is reported. (author)

  1. Superoxide radical and UV irradiation in ultrasound assisted oxidative desulfurization (UAOD): A potential alternative for greener fuels

    Science.gov (United States)

    Chan, Ngo Yeung

    This study is aimed at improving the current ultrasound assisted oxidative desulfurization (UAOD) process by utilizing superoxide radical as oxidant. Research was also conducted to investigate the feasibility of ultraviolet (UV) irradiation-assisted desulfurization. These modifications can enhance the process with the following achievements: (1) Meet the upcoming sulfur standards on various fuels including diesel fuel oils and residual oils; (2) More efficient oxidant with significantly lower consumption in accordance with stoichiometry; (3) Energy saving by 90%; (4) Greater selectivity in petroleum composition. Currently, the UAOD process and subsequent modifications developed in University of Southern California by Professor Yen's research group have demonstrated high desulfurization efficiencies towards various fuels with the application of 30% wt. hydrogen peroxide as oxidant. The UAOD process has demonstrated more than 50% desulfurization of refractory organic sulfur compounds with the use of Venturella type catalysts. Application of quaternary ammonium fluoride as phase transfer catalyst has significantly improved the desulfurization efficiency to 95%. Recent modifications incorporating ionic liquids have shown that the modified UAOD process can produce ultra-low sulfur, or near-zero sulfur diesels under mild conditions with 70°C and atmospheric pressure. Nevertheless, the UAOD process is considered not to be particularly efficient with respect to oxidant and energy consumption. Batch studies have demonstrated that the UAOD process requires 100 fold more oxidant than the stoichiometic requirement to achieve high desulfurization yield. The expected high costs of purchasing, shipping and storage of the oxidant would reduce the practicability of the process. The excess use of oxidant is not economically desirable, and it also causes environmental and safety issues. Post treatments would be necessary to stabilize the unspent oxidant residual to prevent the waste

  2. Potential inhibitors from wet oxidation of wheat straw and their effect on growth and ethanol production by Thermoanaerobacter mathranii

    DEFF Research Database (Denmark)

    Klinke, Helene Bendstrup; Thomsen, A.B.; Ahring, Birgitte Kiær

    2001-01-01

    Alkaline wet oxidation (WO) (using water, 6.5 g/l sodium carbonate, and 12 bar oxygen at 195 degreesC) was used for pre-treating wheat straw (60 g/l), resulting in a hemicellulose-rich hydrolysate and a cellulose-rich solid fraction. The hydrolysate consisted of soluble hemicellulose (9 g....../l), aliphatic carboxylic acids (6 g/l), phenols (0.27 g/l or 1.7 mM), and 2-furoic acid (0.007 g/l). The wet-oxidized wheat straw hydrolysate caused no inhibition of ethanol yield by the anaerobic thermophilic bacterium Thermoanaerobacter mathranii. Nine phenols and 2-furoic acid, identified to be present...

  3. Changing redox potential by controlling soil moisture and addition of inorganic oxidants to dissipate pentachlorophenol in different soils

    International Nuclear Information System (INIS)

    Lin Jiajiang; He Yan; Xu Jianming

    2012-01-01

    The potential for dissipation of pentachlorophenol (PCP) was investigated in soils from four different sites in China. These were an umbraqualf (Soil 1), a Plinthudult (Soil 2), a Haplustalf (Soil 3) and an Argiustoll (Soil 4) which were either flooded, to produce anaerobic conditions, or incubated aerobically at 60% water-holding capacity (WHC). The dissipation of PCP in Soil 1 at 60% WHC was higher than under flooded condition, while the opposite occurred in the other three soils. Under flooded conditions, the redox potential decreased significantly in Soil 1 and Soil 4, where sulphate reduction was occurred and the dissipation of PCP was statistically significant (about 96% and 98%, respectively) at the end of incubation. After addition of inorganic oxidants, dissipation of PCP was significantly inhibited by FeCl 3 , while Na 2 SO 4 and NaNO 3 had different effects, depending upon the soil type. - Highlights: ► The extent of the aerobic/anaerobic interface depends upon the soil properties. ► The dissipation of PCP was accelerated in some soils due to the soil-water interface. ► The addition of oxidants inhibited the decrease in soil redox potential. ► Most external oxidants added under flooded condition inhibited PCP dechlorination. - The addition of inorganic oxidants limited the decrease in redox potential and inhibited the reductive dechlorination of pentachlorophenol.

  4. Ab Initio Thermodynamic Modeling of Electrified Metal–Oxide Interfaces: Consistent Treatment of Electronic and Ionic Chemical Potentials

    DEFF Research Database (Denmark)

    Zeng, Zhenhua; Hansen, Martin Hangaard; Greeley, Jeffrey Philip

    2014-01-01

    . In this paper we present a scheme to determine the metal–oxide interface structure at a given set of these environmental parameters based on quantum chemical calculations. As an illustration we determine the structure of a Ni-YSZ anode as a function of electrode potential at 0 and 1000 K. We further describe...

  5. Establishing the potential dependent equilibrium oxide coverage on platinum in alkaline solution and its influence on the oxygen reduction

    DEFF Research Database (Denmark)

    Wiberg, Gustav; Arenz, Matthias

    2012-01-01

    Publication year: 2012 Source:Journal of Power Sources, Volume 217 Gustav K.H. Wiberg, Matthias Arenz The oxidation process of polycrystalline platinum subjected to alkaline solution is re-examined using a combination of cyclic voltammetry and potential hold techniques in Ar, H2 and O2 purged 0.1...

  6. Characterization of apoplast phenolics: Invitro oxidation of acetosyringone results in a rapid prolonged increase in the redox potential

    Science.gov (United States)

    In a previous study we observed that if tobacco cell suspensions were inoculated with certain bacterial strains, several hours later the redox potential of the suspensions would increase (oxidative), as much as 100 mV, and in some cases last more than an hour. To discover possible contributors to t...

  7. A comparative genomic analysis of the oxidative enzymes potentially involved in lignin degradation by Agaricus bisporus

    Science.gov (United States)

    Harshavardhan Doddapaneni; Venkataramanan Subramanian; Bolei Fu; Dan Cullen

    2013-01-01

    The oxidative enzymatic machinery for degradation of organic substrates in Agaricus bisporus (Ab) is at the core of the carbon recycling mechanisms in this fungus. To date, 156 genes have been tentatively identified as part of this oxidative enzymatic machinery, which includes 26 peroxidase encoding genes, nine copper radical oxidase [including three...

  8. Ceriodaphnia dubia as a potential bio-indicator for assessing acute aluminum oxide nanoparticle toxicity in fresh water environment.

    Directory of Open Access Journals (Sweden)

    Sunandan Pakrashi

    Full Text Available Growing nanomaterials based consumer applications have raised concerns about their potential release into the aquatic ecosystems and the consequent toxicological impacts. So environmental monitoring of the nanomaterials in aqueous systems becomes imperative. The current study reveals the potential of Ceriodaphnia dubia (C. dubia as a bio-indicator for aluminum oxide nanoparticles in a fresh water aquatic ecosystem where it occupies an important ecological niche as a primary consumer. This study aims to investigate the aluminium oxide nanoparticle induced acute toxicity on Ceriodaphnia dubia in a freshwater system. The bioavailability of the aluminum oxide nanoparticles has been studied with respect to their aggregation behavior in the system and correlated with the toxicity endpoints. The oxidative stress generated by the particles contributed greatly toward their toxicity. The crucial role of leached aluminium ion mediated toxicity in the later phases (48 h and 72 h in conjunction with the effects from the nano-sized particles in the initial phases (24 h puts forth the dynamics of nanotoxicity in the test system. The internalization of nanoparticles (both gross and systemic uptake as substantiated through the transmission electron microscopy (TEM and inductively coupled plasma optical emission spectral (ICP-OES analysis was another major contributor toward acute toxicity. Concluding the present study, Ceriodaphnia dubia can be a promising candidate for bio-monitoring the aluminium oxide nanoparticles in a fresh water system.

  9. Peracetic acid as a superior oxidant for preparation of [123I]IBZM: a potential dopamine D-2 receptor imaging agent

    International Nuclear Information System (INIS)

    Kung, Meiping; Kung, H.F.

    1989-01-01

    Various oxidizing agents: chloramine-T, hydrogen peroxide, sodium persulfate, m-chloroperoxybenzoic acid and peracetic acid were examined as the oxidant for preparing radioiodinated IBZM ((S)-(-)-3-iodo-2-hydroxy-6-methoxy-N-[(1-ethyl-2-pyrrolidinyl)methyl]benzami de), which is a useful dopamine D-2 receptor imaging agent. Of all the oxidizing agents tested, peracetic acid appears to be the best agent for no-carrier added radioiodination. The advantages of using peracetic acid as the oxidant for the preparation of [ 125 I] or [ 123 I] IBZM include: high radiochemical yield, high radiochemical purity, and short reaction time at room temperature. (Author)

  10. InP/ZnS-graphene oxide and reduced graphene oxide nanocomposites as fascinating materials for potential optoelectronic applications

    Science.gov (United States)

    Samal, Monica; Mohapatra, Priyaranjan; Subbiah, Ramesh; Lee, Chang-Lyoul; Anass, Benayad; Kim, Jang Ah; Kim, Taesung; Yi, Dong Kee

    2013-09-01

    Our recent studies on metal-organic nanohybrids based on alkylated graphene oxide (GO), reduced alkylated graphene oxide (RGO) and InP/ZnS core/shell quantum dots (QDs) are presented. The GO alkylated by octadecylamine (ODA) and the QD bearing a dodecane thiol (DDT) ligand are soluble in toluene. The nanocomposite alkylated-GO-QD (GOQD) is readily formed from the solution mixture. Treatment of the GOQD composite with hydrazine affords a reduced-alkylated-GO-QD (RGOQD) composite. The structure, morphology, photophysical and electrical properties of GOQDs and RGOQDs are studied. The micro-FTIR and Raman studies demonstrate evidence of the QD interaction with GO and RGO through facile intercalation of the alkyl chains. The field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM) images of the GOQD composite show heaps of large QD aggregates piled underneath the GO sheet. Upon reduction to RGOQDs, the QDs become evenly distributed on the graphene bed and the size of the clusters significantly decreases. This also facilitates closer proximity of the QDs to the graphene domains by altering the optoelectronic properties of the RGOQDs. The X-ray photoelectron spectroscopy (XPS) results confirm QDs being retained in the composites, though a small elemental composition change takes place. The XPS and the fluorescence spectra show the presence of an In(Zn)P alloy while the X-ray diffraction (XRD) results show characteristics of the tetragonal indium. The photoluminescence (PL) quenching of QDs in GOQD and RGOQD films determined by the time correlated single photon counting (TCSPC) experiment demonstrates almost complete fluorescence quenching in RGOQDs. The conductance studies demonstrate the differences between GOQDs and RGOQDs. Investigation on the metal-oxide-semiconductor field-effect transistor (nMOSFET) characteristics shows the composite to exhibit p-type channel material properties. The RGOQD exhibits much

  11. MiOXSYS: a novel method of measuring oxidation reduction potential in semen and seminal plasma.

    Science.gov (United States)

    Agarwal, Ashok; Sharma, Rakesh; Roychoudhury, Shubhadeep; Du Plessis, Stefan; Sabanegh, Edmund

    2016-09-01

    To measure oxidative reduction potential (ORP) in semen and seminal plasma and to establish their reference levels. ORP levels were measured in semen and seminal plasma. Tertiary hospital. Twenty-six controls and 33 infertile men. None. Static ORP (sORP) and capacitance ORP (cORP) were measured in semen and seminal plasma at time 0 and 120 minutes. Correlation of ORP was assessed between [1] semen and seminal plasma and [2] time 0 and 120 minutes. The association with sperm parameters was studied in (a) controls and (b) infertile patients, and a receiver operating characteristic curve was generated to establish the sORP cutoff. Semen sORP and cORP levels were associated with seminal plasma levels at time 0 and time 120 minutes. In controls and infertile patients, an inverse relationship of sORP levels was established with concentration and total sperm count in semen as well as seminal plasma at time 0 and 120 minutes. Classification of subjects based on sperm motility showed that subjects with abnormal motility present with poor concentration, total count, morphology, and elevated levels of semen and seminal plasma sORP at time 120 minutes. The sORP cutoff of 1.48 in semen and 2.09 in seminal plasma based on motility was able to distinguish subjects with normal semen quality from those with abnormal semen quality. The MiOXSYS System can reliably measure ORP levels in semen and seminal plasma. ORP levels are not affected by semen age, making this new technology easy to employ in a clinical setting. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  12. Identification of oxidized protein hydrolase as a potential prodrug target in prostate cancer

    International Nuclear Information System (INIS)

    McGoldrick, Christopher A; Jiang, Yu-Lin; Paromov, Victor; Brannon, Marianne; Krishnan, Koyamangalath; Stone, William L

    2014-01-01

    Esterases are often overexpressed in cancer cells and can have chiral specificities different from that of the corresponding normal tissues. For this reason, ester prodrugs could be a promising approach in chemotherapy. In this study, we focused on the identification and characterization of differentially expressed esterases between non-tumorigenic and tumorigenic prostate epithelial cells. Cellular lysates from LNCaP, DU 145, and PC3 prostate cancer cell lines, tumorigenic RWPE-2 prostate epithelial cells, and non-tumorigenic RWPE-1 prostate epithelial cells were separated by native polyacrylamide gel electrophoresis (n-PAGE) and the esterase activity bands visualized using α-naphthyl acetate or α-naphthyl-N-acetylalaninate (ANAA) chiral esters and Fast Blue RR salt. The esterases were identified using nanospray LC/MS-MS tandem mass spectrometry and confirmed by Western blotting, native electroblotting, inhibition assays, and activity towards a known specific substrate. The serine protease/esterase oxidized protein hydrolase (OPH) was overexpressed in COS-7 cells to verify our results. The major esterase observed with the ANAA substrates within the n-PAGE activity bands was identified as OPH. OPH (EC 3.4.19.1) is a serine protease/esterase and a member of the prolyl oligopeptidase family. We found that LNCaP lysates contained approximately 40% more OPH compared to RWPE-1 lysates. RWPE-2, DU145 and PC3 cell lysates had similar levels of OPH activity. OPH within all of the cell lysates tested had a chiral preference for the S-isomer of ANAA. LNCaP cells were stained more intensely with ANAA substrates than RWPE-1 cells and COS-7 cells overexpressing OPH were found to have a higher activity towards the ANAA and AcApNA than parent COS-7 cells. These data suggest that prodrug derivatives of ANAA and AcApNA could have potential as chemotherapeutic agents for the treatment of prostate cancer tumors that overexpress OPH

  13. Simulation of uranium transport with variable temperature and oxidation potential: The computer program THCC [Thermo-Hydro-Chemical Coupling

    International Nuclear Information System (INIS)

    Carnahan, C.L.

    1986-12-01

    A simulator of reactive chemical transport has been constructed with the capabilities of treating variable temperatures and variable oxidation potentials within a single simulation. Homogeneous and heterogeneous chemical reactions are simulated at temperature-dependent equilibrium, and changes of oxidation states of multivalent elements can be simulated during transport. Chemical mass action relations for formation of complexes in the fluid phase are included explicitly within the partial differential equations of transport, and a special algorithm greatly simplifies treatment of reversible precipitation of solid phases. This approach allows direct solution of the complete set of governing equations for concentrations of all aqueous species and solids affected simultaneously by chemical and physical processes. Results of example simulations of transport, along a temperature gradient, of uranium solution species under conditions of varying pH and oxidation potential and with reversible precipitation of uraninite and coffinite are presented. The examples illustrate how inclusion of variable temperature and oxidation potential in numerical simulators can enhance understanding of the chemical mechanisms affecting migration of multivalent waste elements

  14. A predictive model of iron oxide nanoparticles flocculation tuning Z-potential in aqueous environment for biological application

    International Nuclear Information System (INIS)

    Baldassarre, Francesca; Cacciola, Matteo; Ciccarella, Giuseppe

    2015-01-01

    Iron oxide nanoparticles are the most used magnetic nanoparticles in biomedical and biotechnological field because of their nontoxicity respect to the other metals. The investigation of iron oxide nanoparticles behaviour in aqueous environment is important for the biological applications in terms of polydispersity, mobility, cellular uptake and response to the external magnetic field. Iron oxide nanoparticles tend to agglomerate in aqueous solutions; thus, the stabilisation and aggregation could be modified tuning the colloids physical proprieties. Surfactants or polymers are often used to avoid agglomeration and increase nanoparticles stability. We have modelled and synthesised iron oxide nanoparticles through a co-precipitation method, in order to study the influence of surfactants and coatings on the aggregation state. Thus, we compared experimental results to simulation model data. The change of Z-potential and the clusters size were determined by Dynamic Light Scattering. We developed a suitable numerical model to predict the flocculation. The effects of Volume Mean Diameter and fractal dimension were explored in the model. We obtained the trend of these parameters tuning the Z-potential. These curves matched with the experimental results and confirmed the goodness of the model. Subsequently, we exploited the model to study the influence of nanoparticles aggregation and stability by Z-potential and external magnetic field. The highest Z-potential is reached up with a small external magnetic influence, a small aggregation and then a high suspension stability. Thus, we obtained a predictive model of Iron oxide nanoparticles flocculation that will be exploited for the nanoparticles engineering and experimental setup of bioassays

  15. A predictive model of iron oxide nanoparticles flocculation tuning Z-potential in aqueous environment for biological application

    Energy Technology Data Exchange (ETDEWEB)

    Baldassarre, Francesca, E-mail: francesca.baldassarre@unisalento.it [University of Salento, Department of Cultural Heritage (Italy); Cacciola, Matteo, E-mail: matteo.cacciola@unirc.it [University “Mediterranea” of Reggio Calabria, DICEAM (Italy); Ciccarella, Giuseppe, E-mail: giuseppe.ciccarella@unisalento.it [University of Salento, Department of Innovation Engineering (Italy)

    2015-09-15

    Iron oxide nanoparticles are the most used magnetic nanoparticles in biomedical and biotechnological field because of their nontoxicity respect to the other metals. The investigation of iron oxide nanoparticles behaviour in aqueous environment is important for the biological applications in terms of polydispersity, mobility, cellular uptake and response to the external magnetic field. Iron oxide nanoparticles tend to agglomerate in aqueous solutions; thus, the stabilisation and aggregation could be modified tuning the colloids physical proprieties. Surfactants or polymers are often used to avoid agglomeration and increase nanoparticles stability. We have modelled and synthesised iron oxide nanoparticles through a co-precipitation method, in order to study the influence of surfactants and coatings on the aggregation state. Thus, we compared experimental results to simulation model data. The change of Z-potential and the clusters size were determined by Dynamic Light Scattering. We developed a suitable numerical model to predict the flocculation. The effects of Volume Mean Diameter and fractal dimension were explored in the model. We obtained the trend of these parameters tuning the Z-potential. These curves matched with the experimental results and confirmed the goodness of the model. Subsequently, we exploited the model to study the influence of nanoparticles aggregation and stability by Z-potential and external magnetic field. The highest Z-potential is reached up with a small external magnetic influence, a small aggregation and then a high suspension stability. Thus, we obtained a predictive model of Iron oxide nanoparticles flocculation that will be exploited for the nanoparticles engineering and experimental setup of bioassays.

  16. 3-Hydroxylysine, a potential marker for studying radical-induced protein oxidation

    DEFF Research Database (Denmark)

    Morin, B; Bubb, W A; Davies, Michael Jonathan

    1998-01-01

    albumin (BSA) and human low-density lipoprotein (LDL)] and diseased human tissues (atherosclerotic plaques and lens cataractous proteins). This work was aimed at investigating oxidized lysine as a sensitive marker for protein oxidation, as such residues are present on protein surfaces, and are therefore...... likely to be particularly susceptible to oxidation by radicals in bulk solution. HO* attack on lysine in the presence of oxygen, followed by NaBH4 reduction, is shown to give rise to (2S)-3-hydroxylysine [(2S)-2,6-diamino-3-hydroxyhexanoic acid], (2S)-4-hydroxylysine [(2S)-2,6-diamino-4-hydroxyhexanoic...... acid], (2S, 5R)-5-hydroxylysine [(2S,5R)-2,6-diamino-5-hydroxyhexanoic acid], and (2S,5S)-5-hydroxylysine [(2S,5S)-2,6-diamino-5-hydroxyhexanoic acid]. 5-Hydroxylysines are natural products formed by lysyl oxidase and are therefore not good markers of radical-mediated oxidation. The other...

  17. [Potential protective role of nitric oxide and Hsp70 linked to functional foods in the atherosclerosis].

    Science.gov (United States)

    Camargo, Alejandra B; Manucha, Walter

    Atherosclerosis, one of the main pathologic entities considered epidemic and a worldwide public health problem, is currently under constant review as regards its basic determining mechanisms and therapeutic possibilities. In this regard, all patients afflicted with the disease exhibit mitochondrial dysfunction, oxidative stress and inflammation. Interestingly, nitric oxide - a known vasoactive messenger gas - has been closely related to the inflammatory, oxidative and mitochondrial dysfunctional process that characterizes atherosclerosis. In addition, it has recently been demonstrated that alterations in the bioavailability of nitric oxide would induce the expression of heat shock proteins. This agrees with the use of functional foods as a strategy to prevent both vascular aging and the development of atherosclerosis. Finally, a greater knowledge regarding the mechanisms implied in the development of atherosclerosis will enable proposing new and possible hygiene, health and therapeutic interventions. Copyright © 2016 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. Microbiological Diversity Demonstrates the Potential which Collaboratively Metabolize Nitrogen Oxides ( NOx) under Smog Environmental Stress

    Science.gov (United States)

    Chen, X. Z.; Zhao, X. H.; Chen, X. P.

    2018-03-01

    Recently, smoggy weather has become a daily in large part of China because of rapidly economic growth and accelerative urbanization. Stressed on the smoggy situation and economic growth, the green and environment-friendly technology is necessary to reduce or eliminate the smog and promote the sustainable development of economy. Previous studies had confirmed that nitrogen oxides ( NOx ) is one of crucial factors which forms smog. Microorganisms have the advantages of quickly growth and reproduction and metabolic diversity which can collaboratively Metabolize various NOx. This study will design a kind of bacteria & algae cultivation system which can metabolize collaboratively nitrogen oxides in air and intervene in the local nitrogen cycle. Furthermore, the nitrogen oxides can be transformed into nitrogen gas or assembled in protein in microorganism cell by regulating the microorganism types and quantities and metabolic pathways in the system. Finally, the smog will be alleviated or eliminated because of reduction of nitrogen oxides emission. This study will produce the green developmental methodology.

  19. Genomic analysis reveals versatile heterotrophic capacity of a potentially symbiotic sulfur-oxidizing bacterium in sponge

    KAUST Repository

    Tian, Renmao; Wang, Yong; Bougouffa, Salim; Gao, Zhaoming; Cai, Lin; Bajic, Vladimir B.; Qian, Peiyuan

    2014-01-01

    coevolved with the ancient host during establishment of their association. Exclusive distribution in sponge, bacterial detoxification for the host (sulfide oxidation) and the enrichment for symbiotic characteristics (genes-encoding ankyrin) in the SOB genome

  20. Enhancement of nitrite on heme-induced oxidative reactions: A potential toxicological implication.

    Science.gov (United States)

    Lu, Naihao; Chen, Wei; Zhu, Jingjie; Peng, Yi-Yuan

    2012-02-01

    Evidence to support the role of heme as major inducers of oxidative damage is increasingly present. Nitrite (NO(2)(-)) is one of the major end products of NO metabolism. Although the biological significance of heme/NO(2)(-)-mediated protein tyrosine nitration is a subject of great interest, the important roles of NO(2)(-) on heme-dependent redox reaction have been greatly underestimated. In this study, we investigated the influence of NO(2)(-) on heme -dependent oxidative reactions. It was found that NO(2)(-) had the capacity to act as a reducing agent to remove high oxidation states of heme iron. In the reduction of ferryl heme to ferric heme, NO(2)(-) was oxidized to a nitrating agent NO(2), and subsequently, tyrosine residues in bovine serum albumin (BSA) were nitrated. However, the presence of NO(2)(-) surprisingly exerted pro-oxidant effect on heme-H(2)O(2)-induced formation of BSA carbonyls at lower concentrations and enhanced the loss of HepG2 cell viability dose-dependently, which was probably due to the ability of this inorganic compound to efficiently enhance the peroxidase activity and oxidative degradation of heme. These data provide novel evidence that the dietary intake and experimental use of NO(2)(-) in vivo and in vitro would possess the pro-oxidant activity through interfering in heme-dependent oxidative reactions. Besides the classic role in protein tyrosine nitration, the deleterious effects on heme redox reactions may provide new insights into the toxicological implications of NO(2)(-) with cellular heme proteins. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Methionine sulfoxides in serum proteins as potential clinical biomarkers of oxidative stress

    OpenAIRE

    Satoko Suzuki; Yoshio Kodera; Tatsuya Saito; Kazumi Fujimoto; Akari Momozono; Akinori Hayashi; Yuji Kamata; Masayoshi Shichiri

    2016-01-01

    Oxidative stress contributes to the pathophysiology of a variety of diseases, and circulating biomarkers of its severity remains a topic of great interest for researchers. Our peptidomic strategy enables accurate and reproducible analysis of circulating proteins/peptides with or without post-translational modifications. Conventional wisdom holds that hydrophobic methionines exposed to an aqueous environment or experimental handling procedures are vulnerable to oxidation. However, we show that...

  2. Evaluation of the development and yielding potential of Chenopodium quinoa Willd. under the climatic conditions of Europe. Part one: accomodation of Chenopodium quinoa (Willd. to different conditions

    Directory of Open Access Journals (Sweden)

    Krzysztof Gęsiński

    2012-12-01

    Full Text Available Based on the evaluation of selected varieties of Chenopodium quinoa, their requirements were identified; it was shown which varieties demonstrated the best effects in what conditions. It was found that the best varieties for Europe's conditions were E-DK-4-PQCIP and RU-5-PQCIP. E-DK-4-PQCIP variety showed the best effects under the conditions of cluster II which included e.g. Bydgoszcz (Poland and cluster IV which included Southern European countries (Greece and Italy, while the best effects found in RU-5-PQCIP variety were identified in cluster I which included Sweden. E-DK-4-PQCIP variety in cluster II showed a very high yield of green matter and a mean seed yield, and in cluster IV - a very high seed yield and a high yield of green matter.

  3. Increased nitration and carbonylation of proteins in MRL +/+ mice exposed to trichloroethene: Potential role of protein oxidation in autoimmunity

    International Nuclear Information System (INIS)

    Wang Gangduo; Wang Jianling; Ma Huaxian; Khan, M. Firoze

    2009-01-01

    Even though reactive oxygen and nitrogen species (RONS) are implicated as mediators of autoimmune diseases (ADs), little is known about contribution of protein oxidation (carbonylation and nitration) in the pathogenesis of such diseases. The focus of this study was, therefore, to establish a link between protein oxidation and induction and/or exacerbation of autoimmunity. To achieve this, female MRL +/+ mice were treated with trichloroethene (TCE), an environmental contaminant known to induce autoimmune response, for 6 or 12 weeks (10 mmol/kg, i.p., every 4 th day). TCE treatment resulted in significantly increased formation of nitrotyrosine (NT) and induction of iNOS in the serum at both 6 and 12 weeks of treatment, but the response was greater at 12 weeks. Likewise, TCE treatment led to greater NT formation, and iNOS protein and mRNA expression in the livers and kidneys. Moreover, TCE treatment also caused significant increases (∼3 fold) in serum protein carbonyls (a marker of protein oxidation) at both 6 and 12 weeks. Significantly increased protein carbonyls were also observed in the livers and kidneys (2.1 and 1.3 fold, respectively) at 6 weeks, and to a greater extent at 12 weeks (3.5 and 2.1 fold, respectively) following TCE treatment. The increases in TCE-induced protein oxidation (carbonylation and nitration) were associated with significant increases in Th1 specific cytokine (IL-2, IFN-γ) release into splenocyte cultures. These results suggest an association between protein oxidation and induction/exacerbation of autoimmune response. The results present a potential mechanism by which oxidatively modified proteins could contribute to TCE-induced autoimmune response and necessitates further investigations for clearly establishing the role of protein oxidation in the pathogenesis of ADs.

  4. Copper increases the ability of 6-hydroxydopamine to generate oxidative stress and the ability of ascorbate and glutathione to potentiate this effect: potential implications in Parkinson's disease.

    Science.gov (United States)

    Cruces-Sande, Antón; Méndez-Álvarez, Estefanía; Soto-Otero, Ramón

    2017-06-01

    Copper is an essential metal for the function of many proteins related to important cellular reactions and also involved in the synaptic transmission. Although there are several mechanisms involved in copper homeostasis, a dysregulation in this process can result in serious neurological consequences, including degeneration of dopaminergic neurons. 6-Hydroxydopamine is a dopaminergic neurotoxin mainly used in experimental models of Parkinson's disease, whose neurotoxicity has been related to its ability to generate free radicals. In this study, we examined the effects induced by copper on 6-OHDA autoxidation. Our data show that both Cu + and Cu 2+ caused an increase in • OH production by 6-OHDA autoxidation, which was accompanied by an increase in the rate of both p-quinone formation and H 2 O 2 accumulation. The presence of ascorbate greatly enhanced this process by establishing a redox cycle which regenerates 6-OHDA from its p-quinone. However, the presence of glutathione did not change significantly the copper-induced effects. We observed that copper is able to potentiate the ability of 6-OHDA to cause both lipid peroxidation and protein oxidation, with the latter including a reduction in free-thiol content and an increase in carbonyl content. Ascorbate also increases the lipid peroxidation induced by the action of copper and 6-OHDA. Glutathione protects against the copper-induced lipid peroxidation, but does not reduce its potential to oxidize free thiols. These results clearly demonstrate the potential of copper to increase the capacity of 6-OHDA to generate oxidative stress and the ability of ascorbate to enhance this potential, which may contribute to the destruction of dopaminergic neurons. © 2017 International Society for Neurochemistry.

  5. Is Reduction in Yield Potential of Some Brassicaceous Species Due to Aphid Infestation Associated with the Changes in Stomatal Factors of Photosynthesis

    International Nuclear Information System (INIS)

    Razaq, M.; Farooq, M.; Abbas, G.; Rehman, H. M.; Iqbal, M.

    2016-01-01

    Aphids cause heavy yield losses to Brassicaceous species by affecting various physiological and biochemical processes including photosynthesis. In the present study, seasonal activity of aphid population and its impact on some brassicaceous species was assessed. Three brassicaceous species (Brassica campestris, Brassica carinata, Eruca sativa) were grown in field following standard agricultural practices. Plants of control plots retained aphid free by insecticide spray, whereas treatment plots were freely allowed for aphid infestation. There was also intermediate treatment of partial aphid infestation where insecticidal spray was applied two times. Peak populations of both aphid species were observed in the 2nd week of March during which plant photosynthetic attributes were recorded. At the time of maturity, yield attributes were also recorded. From the results, it is obvious that application of insecticide significantly reduced the aphid populations on the three brassicaceous species and enhanced the crop yield. Yield losses due to aphid infestation were maximal in Brassica campestris followed by B. carinata whereas it was minimal in Eruca sativa. Yield losses in Brassica campestris and B. carinata were due to reduction in number of pods per plant, number of seeds per pod and size of seeds, whereas yield losses due to aphid infestation in Eruca sativa was mainly attributed to reduction in number of pods per plant. Although insecticidal spray reduced the aphid population and increased growth and productivity of all brassicaceous species, it did not change photosynthetic capacity of all plants except in Eruca sativa. Moreover, growth and yield reduction was not associated with stomatal factors of photosynthesis. Chlorophyll contents measured as SPAD values were reduced due to aphid infestation which is positively associated with yield reduction. Insecticidal spray increased chlorophyll contents in these three brassicaceous species by reducing aphid population

  6. Yield trends and yield gap analysis of major crops in the world

    OpenAIRE

    Hengsdijk, H.; Langeveld, J.W.A.

    2009-01-01

    This study aims to quantify the gap between current and potential yields of major crops in the world, and the production constraints that contribute to this yield gap. Using an expert-based evaluation of yield gaps and the literature, global and regional yields and yield trends of major crops are quantified, yield gaps evaluated by crop experts, current yield progress by breeding estimated, and different yield projections compared. Results show decreasing yield growth for wheat and rice, but ...

  7. Oxygen-Rich Lithium Oxide Phases Formed at High Pressure for Potential Lithium-Air Battery Electrode.

    Science.gov (United States)

    Yang, Wenge; Kim, Duck Young; Yang, Liuxiang; Li, Nana; Tang, Lingyun; Amine, Khalil; Mao, Ho-Kwang

    2017-09-01

    The lithium-air battery has great potential of achieving specific energy density comparable to that of gasoline. Several lithium oxide phases involved in the charge-discharge process greatly affect the overall performance of lithium-air batteries. One of the key issues is linked to the environmental oxygen-rich conditions during battery cycling. Here, the theoretical prediction and experimental confirmation of new stable oxygen-rich lithium oxides under high pressure conditions are reported. Three new high pressure oxide phases that form at high temperature and pressure are identified: Li 2 O 3 , LiO 2 , and LiO 4 . The LiO 2 and LiO 4 consist of a lithium layer sandwiched by an oxygen ring structure inherited from high pressure ε-O 8 phase, while Li 2 O 3 inherits the local arrangements from ambient LiO 2 and Li 2 O 2 phases. These novel lithium oxides beyond the ambient Li 2 O, Li 2 O 2 , and LiO 2 phases show great potential in improving battery design and performance in large battery applications under extreme conditions.

  8. The potential to control Haemonchus contortus in indigenous South African goats with copper oxide wire particles.

    Science.gov (United States)

    Vatta, A F; Waller, P J; Githiori, J B; Medley, G F

    2009-06-10

    The high prevalence of resistance of Haemonchus contortus to all major anthelmintic groups has prompted investigations into alternative control methods in South Africa, including the use of copper oxide wire particle (COWP) boluses. To assess the efficacy of COWP against H. contortus in indigenous South African goats, 18 male faecal egg-count-negative goats were each given ca.1200 infective larvae of H. contortus three times per week during weeks 1 and 2 of the experiment. These animals made up an "established" infection group (ESTGRP). At the start of week 7, six goats were each given a 2-g COWP bolus orally; six goats received a 4-g COWP bolus each and six animals were not treated. A further 20 goats constituted a "developing" infection group (DEVGRP). At the beginning of week 1, seven of the DEVGRP goats were given a 2-g COWP bolus each; seven goats were treated with a 4-g COWP bolus each and no bolus was given to a further six animals. During weeks 1-6, each of these DEVGRP goats was given ca. 400 H. contortus larvae three times per week. All 38 goats were euthanized for worm recovery from the abomasa and small intestines in week 11. In the ESTGRP, the 2-g and 4-g COWP boluses reduced the worm burdens by 95% and 93%, respectively compared to controls (mean burden+/-standard deviation, SD: 23+/-33, 30+/-56 and 442+/-518 worms, P=0.02). However, in the DEVGRP goats, both the 2-g and 4-g COWP treatments were ineffective in reducing the worm burdens relative to the controls (mean burdens+/-SD: 1102+/-841, 649+/-855, 1051+/-661 worms, P=0.16). Mean liver copper levels did not differ between the ESTGRP goats treated with 2-g COWP, 4-g COWP or no COWP (mean+/-standard error of the mean, SEM, in ppm: 93.7+/-8.3; 101.5+/-8.3; 71.8+/-8.3, P=0.07) nor did they differ between the DEVGRP goats (mean+/-SEM, in ppm: 74.1+/-9.1; 75.4+/-9.1; 74.9+/-10.0, P>0.99). The copper values were considered adequate, but not high, for goats. The COWP boluses have the potential to be used

  9. Effects of Caloric Restriction on Cardiac Oxidative Stress and Mitochondrial Bioenergetics: Potential Role of Cardiac Sirtuins

    Directory of Open Access Journals (Sweden)

    Ken Shinmura

    2013-01-01

    Full Text Available The biology of aging has not been fully clarified, but the free radical theory of aging is one of the strongest aging theories proposed to date. The free radical theory has been expanded to the oxidative stress theory, in which mitochondria play a central role in the development of the aging process because of their critical roles in bioenergetics, oxidant production, and regulation of cell death. A decline in cardiac mitochondrial function associated with the accumulation of oxidative damage might be responsible, at least in part, for the decline in cardiac performance with age. In contrast, lifelong caloric restriction can attenuate functional decline with age, delay the onset of morbidity, and extend lifespan in various species. The effect of caloric restriction appears to be related to a reduction in cellular damage induced by reactive oxygen species. There is increasing evidence that sirtuins play an essential role in the reduction of mitochondrial oxidative stress during caloric restriction. We speculate that cardiac sirtuins attenuate the accumulation of oxidative damage associated with age by modifying specific mitochondrial proteins posttranscriptionally. Therefore, the distinct role of each sirtuin in the heart subjected to caloric restriction should be clarified to translate sirtuin biology into clinical practice.

  10. Potential Health Implications of the Consumption of Thermally-Oxidized Cooking Oils – a Review

    Directory of Open Access Journals (Sweden)

    Falade Ayodeji Osmund

    2017-06-01

    Full Text Available Cooking oils are an integral part of a human diet as they are used in almost all types of culinary practices. They serve as sources of lipids with a significant nutritive value and health benefits which can be attributed to their fatty acid compositions and biological antioxidants. However, cooking oils are usually subjected to thermal oxidation which occurs when fresh cooking oil is heated at high temperatures during various food preparations. Repeated use of cooking oils in the commercial food industry is also common to maximize profit. Thermal oxidation of edible oils had since attracted great attention of nutritionist and researchers given the deteriorative effect such as generation of very cytotoxic compounds, loss of carotenoid, phenolics and vitamins thus reducing the overall antioxidant properties of the oils. Furthermore, several in vivo studies had suggested that consumption of thermally-oxidized cooking oils might not be healthy as it might negatively influence the lipid profile (increased low density lipoprotein (LDL, decreased high density lipoprotein (HDL and elevated cholesterol level, haematological system (alteration in concentration of heamoglobin (Hb, packed cell volume (PCV, white blood cell (WBC count, neutrophil and lymphocyte counts, kidney function, and induce lipid peroxidation and oxidative stress which have been associated with the pathogenesis of various degenerative diseases. Therefore, thermal oxidation seems not to provide any health benefit, as it deteriorates cooking oils and the consumption of the oils may predispose consumers to various disease conditions that may ensue from free radical generation, thereby having deleterious effect on human health.

  11. Enhanced electrochemical oxidation of synthetic dyeing wastewater using SnO2-Sb-doped TiO2-coated granular activated carbon electrodes with high hydroxyl radical yields

    International Nuclear Information System (INIS)

    Li, Xinyang; Wu, Yue; Zhu, Wei; Xue, Fangqing; Qian, Yi; Wang, Chengwen

    2016-01-01

    Highlights: • We study granular activated carbon (GAC) electrodes coated with catalysts. • GAC coated with ATOT demonstrates an impressive ·OH yield. • This electrode can be used in continuous-flow three-dimensional electrode reactors. • We use Rhodamine B as a model organic compound for removal. • The GAC/ATOT performs better than all other electrodes examined. - Abstract: In this study, granular activated carbon (GAC) coated with SnO 2 -Sb doped TiO 2 (GAC/ATOT) with a high hydroxyl radical (·OH) yield is prepared via the sol-gel method. This material is utilized as a granular electrode in a continuous-flow three-dimensional electrode reactor (CTDER) for the enhanced treatment of synthetic dyeing wastewater containing Rhodamine B (RhB). We then characterize the physical properties, electrochemical properties, and electrochemical oxidation performance of the granular electrode. The results show that using the GAC/ATOT electrode in a CTDER significantly enhances the chemical oxygen demand (COD) removal, decreases the energy consumption, and improves the current efficiency of the wastewater. This is primarily attributed to the higher catalytic activity of GAC/ATOT for ·OH production compared to that of other candidates, such as TiO 2 coated GAC (GAC/T), Sb doped SnO 2 coated GAC (GAC/ATO), and pure GAC. The mechanism of the enhanced electrochemical oxidation afforded by using GAC/ATOT indicates that the high ·OH yield in the reactor packed with GAC/ATOT electrodes contributes to the enhanced electrochemical oxidation performance with respect to organic compounds.

  12. Marine phospholipids: The current understanding of their oxidation mechanisms and potential uses for food fortification

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng; Nielsen, Nina Skall; Baron, Caroline P.

    2017-01-01

    reactions, namely, Strecker aldehydes, pyrroles, oxypolymers, and other impurities that may positively or negatively affect the oxidative stability and quality of marine PL. This review was undertaken to provide the industry and academia with an overview of the current understanding of the quality changes......There is a growing interest in using marine phospholipids (PL) as ingredient for food fortification due to their numerous health benefits. However, the use of marine PL for food fortification is a challenge due to the complex nature of the degradation products that are formed during the handling...... and storage of marine PL. For example, nonenzymatic browning reactions may occur between lipid oxidation products and primary amine group from phosphatidylethanolamine or amino acid residues that are present inmarine PL. Therefore, marine PL contain products from nonenzymatic browning and lipid oxidation...

  13. The Arsenite Oxidation Potential of Native Microbial Communities from Arsenic-Rich Freshwaters.

    Science.gov (United States)

    Fazi, Stefano; Crognale, Simona; Casentini, Barbara; Amalfitano, Stefano; Lotti, Francesca; Rossetti, Simona

    2016-07-01

    Microorganisms play an important role in speciation and mobility of arsenic in the environment, by mediating redox transformations of both inorganic and organic species. Since arsenite [As(III)] is more toxic than arsenate [As(V)] to the biota, the microbial driven processes of As(V) reduction and As(III) oxidation may play a prominent role in mediating the environmental impact of arsenic contamination. However, little is known about the ecology and dynamics of As(III)-oxidizing populations within native microbial communities exposed to natural high levels of As. In this study, two techniques for single cell quantification (i.e., flow cytometry, CARD-FISH) were used to analyze the structure of aquatic microbial communities across a gradient of arsenic (As) contamination in different freshwater environments (i.e., groundwaters, surface and thermal waters). Moreover, we followed the structural evolution of these communities and their capacity to oxidize arsenite, when experimentally exposed to high As(III) concentrations in experimental microcosms. Betaproteobacteria and Deltaproteobacteria were the main groups retrieved in groundwaters and surface waters, while Beta and Gammaproteobacteria dominated the bacteria community in thermal waters. At the end of microcosm incubations, the communities were able to oxidize up to 95 % of arsenite, with an increase of Alphaproteobacteria in most of the experimental conditions. Finally, heterotrophic As(III)-oxidizing strains (one Alphaproteobacteria and two Gammaproteobacteria) were isolated from As rich waters. Our findings underlined that native microbial communities from different arsenic-contaminated freshwaters can efficiently perform arsenite oxidation, thus contributing to reduce the overall As toxicity to the aquatic biota.

  14. Eco-friendly approach towards green synthesis of zinc oxide nanocrystals and its potential applications.

    Science.gov (United States)

    Velmurugan, Palanivel; Park, Jung-Hee; Lee, Sang-Myeong; Yi, Young-Joo; Cho, Min; Jang, Jum-Suk; Myung, Hyun; Bang, Keuk-Soo; Oh, Byung-Taek

    2016-09-01

    In the present study, we investigated a novel green route for synthesis of zinc oxide (ZnO) nanocrystals using Prunus × yedoensis Matsumura leaf extract as a reducing agent without using any surfactant or external energy. Standard characterization studies were carried out to confirm the obtained product using UV-Vis spectra, SEM-EDS, FTIR, TEM, and XRD. In addition, the synthesized ZnO nanocrystals were coated onto fabric and leather samples to study their bacteriostatic effect against odor-causing bacteria Brevibacterium linens and Staphylococcus epidermidis. Zinc oxide nanocrystal-coated fabric and leather showed good activity against both bacteria.

  15. Evaluation of Antiproliferative Potential of Cerium Oxide Nanoparticles on HeLa Human Cervical Tumor Cell

    Directory of Open Access Journals (Sweden)

    Zoriţa Diaconeasa

    2015-05-01

    Full Text Available Cerium oxide nanoparticles (CeO2 nanoparticles as nanomaterials have promising biomedical applications. In this paper, the cytotoxicity induced by CONPs human cervical tumor cells was investigated. Cerium oxide nanoparticles were synthesized using the precipitation method. The nanoparticles were found to inhibit the proliferation of HeLa human cervical tumor cells in a dose dependent manner but did not showed to be cytotoxic as analyzed by MTT assay. The administrated treatment decreased the HeLa cell viability cells from 100% to 65% at the dose of 100 μg/mL.

  16. Antigen retrieval prior to on-tissue digestion of formalin-fixed paraffin-embedded tumour tissue sections yields oxidation of proline residues.

    Science.gov (United States)

    Djidja, Marie-Claude; Claude, Emmanuelle; Scriven, Peter; Allen, David W; Carolan, Vikki A; Clench, Malcolm R

    2017-07-01

    MALDI-mass spectrometry imaging (MALDI-MSI) has been shown to allow the study of protein distribution and identification directly within formalin-fixed paraffin-embedded (FFPE) tissue sections. However, direct protein identification from tissue sections remains challenging due to signal interferences and/or existing post-translational or other chemical modifications. The use of antigen retrieval (AR) has been demonstrated for unlocking proteins prior to in situ enzymatic digestion and MALDI-MSI analysis of FFPE tissue sections. In the work reported here, the identification of proline oxidation, which may occur when performing the AR protocol, is described. This facilitated and considerably increased the number of identified peptides when adding proline oxidation as a variable modification to the MASCOT search criteria. This article is part of a Special Issue entitled: MALDI Imaging, edited by Dr. Corinna Henkel and Prof. Peter Hoffmann. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Potential impact of microbial activity on the oxidant capacity and organic carbon budget in clouds

    Science.gov (United States)

    Vaïtilingom, Mickael; Deguillaume, Laurent; Vinatier, Virginie; Sancelme, Martine; Amato, Pierre; Chaumerliac, Nadine; Delort, Anne-Marie

    2013-01-01

    Within cloud water, microorganisms are metabolically active and, thus, are expected to contribute to the atmospheric chemistry. This article investigates the interactions between microorganisms and the reactive oxygenated species that are present in cloud water because these chemical compounds drive the oxidant capacity of the cloud system. Real cloud water samples with contrasting features (marine, continental, and urban) were taken from the puy de Dôme mountain (France). The samples exhibited a high microbial biodiversity and complex chemical composition. The media were incubated in the dark and subjected to UV radiation in specifically designed photo-bioreactors. The concentrations of H2O2, organic compounds, and the ATP/ADP ratio were monitored during the incubation period. The microorganisms remained metabolically active in the presence of ●OH radicals that were photo-produced from H2O2. This oxidant and major carbon compounds (formaldehyde and carboxylic acids) were biodegraded by the endogenous microflora. This work suggests that microorganisms could play a double role in atmospheric chemistry; first, they could directly metabolize organic carbon species, and second, they could reduce the available source of radicals through their oxidative metabolism. Consequently, molecules such as H2O2 would no longer be available for photochemical or other chemical reactions, which would decrease the cloud oxidant capacity.

  18. Anti-leukemic potential of methyl-cobalamin inactivation by nitrous oxide

    NARCIS (Netherlands)

    J. Abels; A.C.M. Kroes (Aloys C.M.); A.A.M. Ermens (Anton); J. van Kapel (Jan); M. Schoester (Martijn); L.J.M. Spijkers (L. J M); J. Lindemans (Jan)

    1990-01-01

    textabstractMyelo‐cytotoxicity of extended nitrous oxide (N2O) inhalation was described almost forty years ago and then incidentally applied already with temporary success for suppressing leukemia. In 1948 the accompanying megaloblastic maturation arrest was explained by inactivation of the

  19. Potential behavioral and pro-oxidant effects of Petiveria alliacea L. extract in adult rats.

    Science.gov (United States)

    de Andrade, Thaís Montenegro; de Melo, Ademar Soares; Dias, Rui Guilherme Cardoso; Varela, Everton Luís Pompeu; de Oliveira, Fábio Rodrigues; Vieira, José Luís Fernandes; de Andrade, Marcieni Ataíde; Baetas, Ana Cristina; Monteiro, Marta Chagas; Maia, Cristiane do Socorro Ferraz

    2012-09-28

    Petiveria alliacea (Phytolaccaceae) is a perennial shrub indigenous to the Amazon Rainforest and tropical areas of Central and South America, the Caribbean, and sub-Saharan Africa. In folk medicine, Petiveria alliacea has a broad range of therapeutic properties; however, it is also associated with toxic effects. The present study evaluated the putative effects of Petiveria alliacea on the central nervous system, including locomotor activity, anxiety, depression-like behavior, and memory, and oxidative stress. Two-month-old male and female Wistar rats (n=7-10 rats/group) were administered with 900 mg/kg of hydroalcoholic extracts of Petiveria alliacea L. The behavioral assays included open-field, forced swimming, and elevated T-maze tests. The oxidative stress levels were measured in rat blood samples after behavioral assays and methemoglobin levels were measured in vitro. Consistent with previous reports, Petiveria alliacea increased locomotor activity. It also exerted previously unreported anxiolytic and antidepressant effects in behavioral tests. In the oxidative stress assays, the Petiveria alliacea extract decreased Trolox equivalent antioxidant capacity levels and increased methemoglobin levels, which was related to the toxic effects. The Petiveria alliacea extract exerted motor stimulatory and anxiolytic effects in the OF test, antidepressant effects in the FS test, and elicited memory improvement in ETM. Furthermore, the Petiveria alliacea extract also exerted pro-oxidant effects in vitro and in vivo, inhibiting the antioxidant status and increasing MetHb levels in human plasma, respectively. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  20. Therapeutic potentials of Houttuynia cordata Thunb. against inflammation and oxidative stress: A review.

    Science.gov (United States)

    Shingnaisui, Khanchuila; Dey, Tapan; Manna, Prasenjit; Kalita, Jatin

    2018-06-28

    Houttuynia cordata Thunb. (Family: Saururaceae) is an herbaceous perennial plant that grows in moist and shady places. The plant is well known among the people of diverse cultures across Japan, Korea, China and North-East India for its medicinal properties. Traditionally the plant is used for its various beneficial properties against inflammation, pneumonia, severe acute respiratory syndrome, muscular sprain, stomach ulcer etc. Oxidative stress and inflammation were found to be linked with most of the diseases in recent times. Many ancient texts from Chinese Traditional Medicine, Ayurveda and Siddha, and Japanese Traditional medicine have documented the efficacy of H. cordata against oxidative stress and inflammation. This review aims to provide up-to-date and comprehensive information on the efficacy of H. cordata extracts as well as its bioactive compounds both in vitro and in vivo, against oxidative stress and inflammation MATERIALS AND METHODS: Relevant information on H. cordata against oxidative stress and inflammation were collected from the established scientific databases such as NCBI, Web of Science, ScienceDirect, Elsevier, and Springer. Additionally, a few books and magazines were also consulted to get the important information. Herbal medicines or plant products were traditionally being used for treating the oxidative stress and inflammation related diseases in diverse communities across the world. Scientifically, H. cordata has shown to target several signaling pathways and found to effectively reduce the oxidative stress and inflammation. Phyto-constituents such as afzelin, hyperoside and quercitrin have shown to reduce inflammation both in vitro and in vivo models. These molecules were also shown to have strong antioxidant properties both in vivo and in vitro models. H. cordata extracts and its bioactive molecules were shown to have both anti-inflammatory and anti-oxidative properties. As both in vitro and in vivo studies were shown that H. cordata

  1. Non-oxidative and oxidative torrefaction characterization and SEM observations of fibrous and ligneous biomass

    International Nuclear Information System (INIS)

    Chen, Wei-Hsin; Lu, Ke-Miao; Lee, Wen-Jhy; Liu, Shih-Hsien; Lin, Ta-Chang

    2014-01-01

    Highlights: • Non-oxidative and oxidative torrefaction of biomass is studied. • Two fibrous biomasses and two ligneous biomasses are tested. • SEM observations of four biomasses are provided. • Fibrous biomass is more sensitive to O 2 concentration than ligneous biomass. • The performance of non-oxidative torrefaction is better than that of oxidative torrefaction. - Abstract: Oxidative torrefaction is a method to reduce the operating cost of upgrading biomass. To understand the potential of oxidative torrefaction and its impact on the internal structure of biomass, non-oxidative and oxidative torrefaction of two fibrous biomass materials (oil palm fiber and coconut fiber) and two ligneous ones (eucalyptus and Cryptomeria japonica) at 300 °C for 1 h are studied and compared with each other. Scanning electron microscope (SEM) observations are also performed to explore the impact of torrefaction atmosphere on the lignocellulosic structure of biomass. The results indicate that the fibrous biomass is more sensitive to O 2 concentration than the ligneous biomass. In oxidative torrefaction, an increase in O 2 concentration decreases the solid yield. The energy yield is linearly proportional to the solid yield, which is opposite to the behavior of non-oxidative torrefaction. The performance of non-oxidative torrefaction is better than that of oxidative torrefaction. As a whole, ligneous biomass can be torrefied in oxidative environments at lower O 2 concentrations, whereas fibrous biomass is more suitable for non-oxidative torrefaction

  2. Evaluation of yield and identifying potential regions for Saffron (Crocus sativus L. cultivation in Khorasan Razavi province according to temperature parameters

    Directory of Open Access Journals (Sweden)

    Moein Tosan

    2015-04-01

    Full Text Available Saffron is cultivated in most part of Iran, because of low water requirement and well adaptation to diverse environmental condition. In recent years, for many reasons such as low water requirement, saffron cultivation areas has been increased especially in Khorasan Razavi province. Temperature is one of the most important factors in saffron flowering phenomena. The aim of this research was to evaluate the response of saffron to temperature in Khorasan Razavi province counties (Torbat-e-Heydarieh, Gonabad, Nishabour, Sabzevar and Ghoochan. Climatic data (monthly minimum, average, maximum temperatures and diurnal temperature range and saffron yield data were collected for past 20 years period. The stepwise regression methods were used to remove extra parameters and only keep the most important ones. By using these equations and ArcGIS software zoning, Spline method was find the best for saffron crop zoning. The results of linear regression in Gonabad showed that minimum, maximum and average temperature and also diurnal temperature range in March and April months had the greatest impact on saffron yield. For each of the four indices (the minimum, maximum and average temperature and also diurnal temperature range the best area for saffron cultivation was the southern part of the province (particularly Gonabad; so by increasing distance from this area to north areas (such as Kashmar, Torbat-e-Heydarieh, Sabzevar, Nishabour, Mashhad and finally Ghoochan saffron yield reduced by 30 to 50 percent. Therefore, the northern areas of the province had relatively low saffron yield. According to result of this research, saffron yield in Khorasan Razavi province was significantly influenced by temperature parameters. Flowering which basically is the most important stage of plant growth, is directly setting up with temperature.

  3. Induction of oxidative DNA damage by mesalamine in the presence of copper: A potential mechanism for mesalamine anticancer activity

    International Nuclear Information System (INIS)

    Zimmerman, Ryan P.; Jia, Zhenquan; Zhu, Hong; Vandjelovic, Nathan; Misra, Hara P.; Wang, Jianmin; Li, Yunbo

    2011-01-01

    Mesalamine is the first line pharmacologic intervention for patients with ulcerative colitis, and recent epidemiologic studies have demonstrated a protective association between therapeutic use of the drug and colorectal carcinoma. However, the mechanism by which this protection is afforded has yet to be elucidated. Because copper is found at higher than normal concentrations in neoplastic cell nuclei and is known to interact with phenolic compounds to generate reactive oxygen species, we investigated whether the reaction of mesalamine/copper was able to induce oxidative DNA strand breaks in φX-174 RF I plasmid DNA, and the various components of the mechanism by which the reaction occurred. Plasmid DNA strand breaks were induced by pharmacologically relevant concentrations of mesalamine in the presence of a micromolar concentration of Cu(II), and damage was inhibited by bathocuproinedisulfonic acid (BCS) and catalase. Further, we showed that the reaction of copper with mesalamine consumed molecular oxygen, which was inhibited by BCS. Electron paramagnetic resonance spectral analysis of the reaction of copper/mesalamine indicated the presence of the hydroxyl radical, which was inhibited by both BCS and catalase. This study demonstrates for the first time that through a copper-redox cycling mechanism, the copper-mediated oxidation of mesalamine is a pro-oxidant interaction that generates hydroxyl radicals which may participate in oxidative DNA damage. These results demonstrate a potential mechanism of the anticancer effects of mesalamine in patients with ulcerative colitis.

  4. Tetrahydrocannabinol Induces Brain Mitochondrial Respiratory Chain Dysfunction and Increases Oxidative Stress: A Potential Mechanism Involved in Cannabis-Related Stroke

    Directory of Open Access Journals (Sweden)

    Valérie Wolff

    2015-01-01

    Full Text Available Cannabis has potential therapeutic use but tetrahydrocannabinol (THC, its main psychoactive component, appears as a risk factor for ischemic stroke in young adults. We therefore evaluate the effects of THC on brain mitochondrial function and oxidative stress, key factors involved in stroke. Maximal oxidative capacities Vmax (complexes I, III, and IV activities, Vsucc (complexes II, III, and IV activities, Vtmpd (complex IV activity, together with mitochondrial coupling (Vmax/V0, were determined in control conditions and after exposure to THC in isolated mitochondria extracted from rat brain, using differential centrifugations. Oxidative stress was also assessed through hydrogen peroxide (H2O2 production, measured with Amplex Red. THC significantly decreased Vmax (−71%; P<0.0001, Vsucc (−65%; P<0.0001, and Vtmpd (−3.5%; P<0.001. Mitochondrial coupling (Vmax/V0 was also significantly decreased after THC exposure (1.8±0.2 versus 6.3±0.7; P<0.001. Furthermore, THC significantly enhanced H2O2 production by cerebral mitochondria (+171%; P<0.05 and mitochondrial free radical leak was increased from 0.01±0.01 to 0.10±0.01% (P<0.001. Thus, THC increases oxidative stress and induces cerebral mitochondrial dysfunction. This mechanism may be involved in young cannabis users who develop ischemic stroke since THC might increase patient’s vulnerability to stroke.

  5. Glyceraldehyde-3-phosphate dehydrogenase aggregation inhibitor peptide: A potential therapeutic strategy against oxidative stress-induced cell death.

    Science.gov (United States)

    Itakura, Masanori; Nakajima, Hidemitsu; Semi, Yuko; Higashida, Shusaku; Azuma, Yasu-Taka; Takeuchi, Tadayoshi

    2015-11-13

    The glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has multiple functions, including mediating oxidative stress-induced neuronal cell death. This process is associated with disulfide-bonded GAPDH aggregation. Some reports suggest a link between GAPDH and the pathogenesis of several oxidative stress-related diseases. However, the pathological significance of GAPDH aggregation in disease pathogenesis remains unclear due to the lack of an effective GAPDH aggregation inhibitor. In this study, we identified a GAPDH aggregation inhibitor (GAI) peptide and evaluated its biological profile. The decapeptide GAI specifically inhibited GAPDH aggregation in a concentration-dependent manner. Additionally, the GAI peptide did not affect GAPDH glycolytic activity or cell viability. The GAI peptide also exerted a protective effect against oxidative stress-induced cell death in SH-SY5Y cells. This peptide could potentially serve as a tool to investigate GAPDH aggregation-related neurodegenerative and neuropsychiatric disorders and as a possible therapy for diseases associated with oxidative stress-induced cell death. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. GAMMA RADIATION INTERACTS WITH MELANIN TO ALTER ITS OXIDATION-REDUCTION POTENTIAL AND RESULTS IN ELECTRIC CURRENT PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Turick, C.; Ekechukwu, A.; Milliken, C.

    2011-05-17

    The presence of melanin pigments in organisms is implicated in radioprotection and in some cases, enhanced growth in the presence of high levels of ionizing radiation. An understanding of this phenomenon will be useful in the design of radioprotective materials. However, the protective mechanism of microbial melanin in ionizing radiation fields has not yet been elucidated. Here we demonstrate through the electrochemical techniques of chronoamperometry, chronopotentiometry and cyclic voltammetry that microbial melanin is continuously oxidized in the presence of gamma radiation. Our findings establish that ionizing radiation interacts with melanin to alter its oxidation-reduction potential. Sustained oxidation resulted in electric current production and was most pronounced in the presence of a reductant, which extended the redox cycling capacity of melanin. This work is the first to establish that gamma radiation alters the oxidation-reduction behavior of melanin, resulting in electric current production. The significance of the work is that it provides the first step in understanding the initial interactions between melanin and ionizing radiation taking place and offers some insight for production of biomimetic radioprotective materials.

  7. Protective property of mulberry digest against oxidative stress - A potential approach to ameliorate dietary acrylamide-induced cytotoxicity.

    Science.gov (United States)

    Zhang, Linxia; Xu, Yang; Li, Yuting; Bao, Tao; Gowd, Vemana; Chen, Wei

    2017-09-01

    The aim of this study was investigating the protective effect of mulberry digest (MBD) on acrylamide-induced oxidative stress. Composition analysis of MBD revealed that it contained six major phenolic compounds (quercetin-3-O-rutinoside, quercetin hexoside, quercetin rhamnosylhexoside hexoside, kaempferol rhamnosylhexoside, cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside). After in vitro digestion, the contents of two anthocyanins were both decreased significantly, while the contents of four flavonoid glycosides were all increased. In addition, MBD was found to successfully suppress acrylamide-induced ROS overproduction, restore the mitochondrial membrane potential, and inhibit the mitochondrial membrane lipid peroxidation and glutathione depletion. More interestingly, the protective effect of MBD against acrylamide-induced oxidative damage was enhanced compared with mulberry fruits without digestion (MBE). Further study revealed that MBD enhanced the cell resistance capacity to acrylamide-induced oxidative stress, rather than its direct reaction with acrylamide. Overall, our results indicate that MBD provides a potent protection against acrylamide-induced oxidative stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Polyaniline: Aniline oxidation with strong and weak oxidants under various acidity

    Energy Technology Data Exchange (ETDEWEB)

    Bláha, Michal, E-mail: blaha@imc.cas.cz [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6 (Czech Republic); Trchová, Miroslava; Bober, Patrycja; Morávková, Zuzana [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6 (Czech Republic); Prokeš, Jan [Charles University, Faculty of Mathematics and Physics, 180 00 Prague 8 (Czech Republic); Stejskal, Jaroslav [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6 (Czech Republic)

    2017-06-15

    Aniline was oxidized with three strong inorganic oxidants (ammonium peroxydisulfate, cerium(IV) sulfate, potassium dichromate), two weak inorganic oxidants (iron(III) chloride, silver nitrate), and one organic oxidant (p-benzoquinone) in aqueous solutions of methanesulfonic acid (MSA) of various concentration. Whereas oxidation of aniline with ammonium peroxydisulfate yielded high-molecular-weight conducting polyaniline (PANI) in the whole acidity range, the oxidation with cerium(IV) sulfate led also to a single product close to PANI with considerably lower molecular weight and lower conductivity. Potassium dichromate gave PANI only at high concentration of MSA. The use of iron(III) chloride yielded composite mixtures of PANI and low-molecular-weight aniline oligomers. The oxidation of aniline with silver nitrate led to composites of silver and an organic part, which was constituted either by aniline oligomers or conducting polyaniline or both. p-Benzoquinone as oxidant produced mainly aniline oligomers with poor conductivity and 2,5-dianilino-p-benzoquinone-like structure detected in FTIR and Raman spectra when oxidation proceeded with weak oxidants. A general model of oxidation with strong and weak oxidants was formulated. - Highlights: • Comparison of aniline oxidation with oxidants of different redox potential. • UV–vis, FTIR and Raman spectroscopies combined with size-exclusion chromatography. • The contents of polymer and oligomers were analyzed and discussed. • General model of aniline oxidation with strong and weak oxidants was formulated.

  9. Potential Protection of Coeloglossum viride var. Bracteatum Extract against Oxidative Stress in Rat Cortical Neurons

    Directory of Open Access Journals (Sweden)

    Zhe Guo

    2013-01-01

    Full Text Available The present study explored the neuroprotective effect of Coeloglossum viride var. bracteatum extract (CE against oxidative stress in rat cortical neurons. The results demonstrated that administration of CE inhibited hydrogen peroxide-induced neurotoxicity tested by MTT, LDH release, and TUNEL assays. We further found that CE inhibited the activation of caspase-3 (Csp3 induced by hydrogen peroxide. Moreover, CE was found to reverse the hydrogen peroxide-induced downregulation of active AKT and Bcl-2. We then showed that the neuroprotective effect of CE was blocked by adding the AKT inhibitor, Ly294002. Thus, our data strongly indicated that CE played a neuroprotective role against oxidative stress-induced neurotoxicity.

  10. Effect of surface roughness and surface modification of indium tin oxide electrode on its potential response to tryptophan

    International Nuclear Information System (INIS)

    Khan, Md. Zaved Hossain; Nakanishi, Takuya; Kuroiwa, Shigeki; Hoshi, Yoichi; Osaka, Tetsuya

    2011-01-01

    Highlights: → We examine factors affecting potential response of ITO electrode to tryptophan. → Surface roughness of ITO electrode affects the stability of its rest potential. → Surface modification is effective for ITO electrode with a certain roughness. → Optimum values of work function exist for potential response of ITO to tryptophan. - Abstract: The effect of surface modification of indium tin oxide (ITO) electrode on its potential response to tryptophan was investigated for ITO substrates with different surface roughness. It was found that a small difference in surface roughness, between ∼1 and ∼2 nm of R a evaluated by atomic force microscopy, affects the rest potential of ITO electrode in the electrolyte. A slight difference in In:Sn ratio at the near surface of the ITO substrates, measured by angle-resolved X-ray photoelectron spectrometry and Auger electron spectroscopy is remarkable, and considered to relate with surface roughness. Interestingly, successive modification of the ITO surface with aminopropylsilane and disuccinimidyl suberate, of which essentiality to the potential response to indole compounds we previously reported, improved the stability of the rest potential and enabled the electrodes to respond to tryptophan in case of specimens with R a values ranging between ∼2 and ∼3 nm but not for those with R a of ∼1 nm. It was suggested that there are optimum values of effective work function of ITO for specific potential response to tryptophan, which can be obtained by the successive modification of ITO surface.

  11. High-temperature steam oxidation testing of select advanced replacement alloys for potential core internals

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Lizhen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pint, Bruce A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-05-19

    Coupons from a total of fourteen commercial and custom fabricated alloys were exposed to 1 bar full steam with ~10 ppb oxygen content at 600 and 650°C. The coupons were weighed at 500-h intervals with a total exposure time of 5,000 h. The fourteen alloys are candidate alloys selected under the ARRM program, which include three ferritic steels (Grade 92, 439, and 14YWT), three austenitic stainless steels (316L, 310, and 800), seven Ni-base superalloys (X750, 725, C22, 690, 625, 625 direct-aging, and 625- plus), and one Zr-alloy (Zr–2.5Nb). Among the alloys, 316L and X750 are served as reference alloys for low- and high-strength alloys, respectively. The candidate Ni-base superalloy 718 was procured too late to be included in the tests. The corrosion rates of the candidate alloys can be approximately interpreted by their Cr, Ni and Fe content. The corrosion rate was significantly reduced with increasing Cr content and when Ni content is above ~15 wt%, but not much further reduced when Fe content is less than ~55 wt%. Simplified thermodynamics analyses of the alloy oxidation provided reasonable indications for the constituents of oxide scales formed on the alloys and explanations for the porosity and exfoliation phenomena because of the nature of specific types of oxides.

  12. Genomic analysis reveals versatile heterotrophic capacity of a potentially symbiotic sulfur-oxidizing bacterium in sponge

    KAUST Repository

    Tian, Renmao

    2014-08-29

    Sulfur-reducing bacteria (SRB) and sulfur-oxidizing bacteria (SOB) play essential roles in marine sponges. However, the detailed characteristics and physiology of the bacteria are largely unknown. Here, we present and analyse the first genome of sponge-associated SOB using a recently developed metagenomic binning strategy. The loss of transposase and virulence-associated genes and the maintenance of the ancient polyphosphate glucokinase gene suggested a stabilized SOB genome that might have coevolved with the ancient host during establishment of their association. Exclusive distribution in sponge, bacterial detoxification for the host (sulfide oxidation) and the enrichment for symbiotic characteristics (genes-encoding ankyrin) in the SOB genome supported the bacterial role as an intercellular symbiont. Despite possessing complete autotrophic sulfur oxidation pathways, the bacterium developed a much more versatile capacity for carbohydrate uptake and metabolism, in comparison with its closest relatives (Thioalkalivibrio) and to other representative autotrophs from the same order (Chromatiales). The ability to perform both autotrophic and heterotrophic metabolism likely results from the unstable supply of reduced sulfur in the sponge and is considered critical for the sponge-SOB consortium. Our study provides insights into SOB of sponge-specific clade with thioautotrophic and versatile heterotrophic metabolism relevant to its roles in the micro-environment of the sponge body. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  13. Enhanced degradation of chitosan by applying plasma treatment in combination with oxidizing agents for potential use as an anticancer agent.

    Science.gov (United States)

    Chokradjaroen, Chayanaphat; Rujiravanit, Ratana; Watthanaphanit, Anyarat; Theeramunkong, Sewan; Saito, Nagahiro; Yamashita, Kazuko; Arakawa, Ryuichi

    2017-07-01

    Solution plasma (SP) treatment in combination with oxidizing agents, i.e., hydrogen peroxide (H 2 O 2 ), potassium persulfate (K 2 S 2 O 8 ) and sodium nitrite (NaNO 2 ) were adopted to chitosan degradation in order to achieve fast degradation rate, low chemicals used and high yield of low-molecular-weight chitosan and chitooligosaccharide (COS). Among the studied oxidizing agents, H 2 O 2 was found to be the best choice in terms of appreciable molecular weight reduction without major change in chemical structure of the degraded products of chitosan. By the combination with SP treatment, dilute solution of H 2 O 2 (4-60mM) was required for effective degradation of chitosan. The combination of SP treatment and dilute solution of H 2 O 2 (60mM) resulted in the great reduction of molecular weight of chitosan and water-soluble chitosan was obtained as a major product. The resulting water-soluble chitosan was precipitated to obtain COS. An inhibitory effect against cervical cancer cell line (HeLa cells) of COS was also examined. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Oxidative potential of size-fractionated atmospheric aerosol in urban and rural sites across Europe.

    Science.gov (United States)

    Shafer, Martin M; Hemming, Jocelyn D C; Antkiewicz, Dagmara S; Schauer, James J

    2016-07-18

    In this study we applied several assays, an in vitro rat alveolar macrophage model, a chemical ROS probe (DTT, dithiothreitol), and cytokine induction (TNFα) to examine relationships between PM-induced generation of reactive oxygen species (ROS) and PM composition, using a unique set of size-resolved PM samples obtained from urban and rural environments across Europe. From April-July 2012, we collected PM from roadside canyon, roadside motorway, and background urban sites in each of six European cities and from three rural sites spanning the continent. A Hi-Vol sampler was used to collect PM in three size classes (PM>7, PM7-3, PM3) and PM was characterized for total elements, and oxidative activity quantified in unfiltered and filtered PM extracts. We measured a remarkable uniformity in air concentrations of ROS and especially DTT activity across the continent. Only a 4-fold difference was documented for DTT across the urban sites and a similar variance was documented for ROS, implying that chemical drivers of oxidative activity are relatively similar between sites. The ROS and DTT specific activity was greater at urban background sites (and also rural sites) than at urban canyon locations. PM3 dominated the size distribution of both ROS activity (86% of total) and DTT activity (76% of total), reflecting both the large contribution of PM3 to total PM mass levels and importantly the higher specific oxidative activity of the PM3 in comparison with the larger particles. The soluble fraction of total activity was very high for DTT (94%) as well as for ROS (64%) in the PM3. However in the larger PM size fractions the contributions of the insoluble components became increasingly significant. The dominance of the insoluble PM drivers of activity was particularly evident in the TNFα data, where the insoluble contribution to cytokine production could be 100-fold greater than that from soluble components. ROS and DTT activity were strongly correlated in the PM3 (r = 0

  15. Making oxidation potentials predictable: Coordination of additives applied to the electronic fine tuning of an iron(II) complex

    KAUST Repository

    Haslinger, Stefan

    2014-11-03

    This work examines the impact of axially coordinating additives on the electronic structure of a bioinspired octahedral low-spin iron(II) N-heterocyclic carbene (Fe-NHC) complex. Bearing two labile trans-acetonitrile ligands, the Fe-NHC complex, which is also an excellent oxidation catalyst, is prone to axial ligand exchange. Phosphine- and pyridine-based additives are used for substitution of the acetonitrile ligands. On the basis of the resulting defined complexes, predictability of the oxidation potentials is demonstrated, based on a correlation between cyclic voltammetry experiments and density functional theory calculated molecular orbital energies. Fundamental insights into changes of the electronic properties upon axial ligand exchange and the impact on related attributes will finally lead to target-oriented manipulation of the electronic properties and consequently to the effective tuning of the reactivity of bioinspired systems.

  16. Making oxidation potentials predictable: Coordination of additives applied to the electronic fine tuning of an iron(II) complex

    KAUST Repository

    Haslinger, Stefan; Kü ck, Jens W.; Hahn, Eva M.; Cokoja, Mirza; Pö thig, Alexander; Basset, Jean-Marie; Kü hn, Fritz

    2014-01-01

    This work examines the impact of axially coordinating additives on the electronic structure of a bioinspired octahedral low-spin iron(II) N-heterocyclic carbene (Fe-NHC) complex. Bearing two labile trans-acetonitrile ligands, the Fe-NHC complex, which is also an excellent oxidation catalyst, is prone to axial ligand exchange. Phosphine- and pyridine-based additives are used for substitution of the acetonitrile ligands. On the basis of the resulting defined complexes, predictability of the oxidation potentials is demonstrated, based on a correlation between cyclic voltammetry experiments and density functional theory calculated molecular orbital energies. Fundamental insights into changes of the electronic properties upon axial ligand exchange and the impact on related attributes will finally lead to target-oriented manipulation of the electronic properties and consequently to the effective tuning of the reactivity of bioinspired systems.

  17. Nitrogen-Based Diazeniumdiolates: Versatile Nitric Oxide-Releasing Compounds for Biomedical Research and Potential Clinical Applications

    Science.gov (United States)

    Saavedra, Joseph E.; Keefer, Larry K.

    2002-12-01

    Nitric oxide-generating ions of the nitrogen-diazeniumdiolate class with the general structure R1R2N-[N(O)NO]1 have been prepared by exposing primary, secondary, and polyamines to nitric oxide (NO). The resulting complexes regenerate bioactive NO at physiological pH with half-lives ranging from 2 seconds to 20 hours. An important goal in our research is to deliver NO to a specific organ or cell type where it is needed without affecting other NO-sensitive parts of the anatomy. By taking advantage of the remarkable chemical versatility of diazeniumdiolates, we have developed general strategies to prepare either tissue-selective NO donor drugs or materials containing NO delivery agents that can be physically placed near the target sites. Inhibition of blood coagulation, induction of penile erection, relief of pulmonary hypertension, and reversal of cerebral vasospasm are a few examples of their potential clinical applications. See Featured Molecules.

  18. Antioxidant activity of mulberry stem extract: A potential used as supplement for oxidative stress-related diseases

    Directory of Open Access Journals (Sweden)

    Phi Phuong Pham

    2017-06-01

    Full Text Available Overproduction of reactive oxygen species is involved in many diseases, including cardiovascular, neurodegenerative diseases, diabetes, cancer, viral and bacterial infections as well as osteoarthritis. Although antioxidant activity of Morus alba L. has been investigated in various parts of this plant, a little attention has been paid to the stems of this plant. Therefore, the present study was designed to systematically investigate the antioxidant activity of M. alba stem extract using various in vitro antioxidant assay systems. The present data showed that the stem extract of M. alba exhibited a hydrogen-donating ability, an ability to quench hydroxyl radicals, having superoxide and nitric oxide scavenging activity as well as iron reducing capacity. This study highlights the potential of this plant for further development as a natural source of antioxidant or as an alternative treatment for oxidative stress-related diseases.

  19. Nitrous oxide in fresh water systems: An estimate for the yield of atmospheric N2O associated with disposal of human waste

    Science.gov (United States)

    Kaplan, W. A.; Elkins, J. W.; Kolb, C. E.; Mcelroy, M. B.; Wofsy, S. C.; Duran, A. P.

    1977-01-01

    The N2O content of waters in the Potomac and Merrimack Rivers was measured on a number of occasions over the period April to July 1977. The concentrations of dissolved N2O exceeded those which would apply in equilibrium with air by factors ranging from about 46 in the Potomac to 1.2 in the Merrimack. Highest concentrations of dissolved N2O were associated with sewage discharges from the vicinity of Washington, D. C., and analysis indicates a relatively high yield, 1.3 to 11%, for prompt conversion of waste nitrogen to N2O. Measurements of dissolved N2O in fresh water ponds near Boston demonstrated that aquatic systems provide both strong sources and sinks for atmospheric N2O.

  20. Two oxidation sites for low redox potential substrates: a directed mutagenesis, kinetic, and crystallographic study on Pleurotus eryngii versatile peroxidase.

    Science.gov (United States)

    Morales, María; Mate, María J; Romero, Antonio; Martínez, María Jesús; Martínez, Ángel T; Ruiz-Dueñas, Francisco J

    2012-11-30

    Versatile peroxidase shares with manganese peroxidase and lignin peroxidase the ability to oxidize Mn(2+) and high redox potential aromatic compounds, respectively. Moreover, it is also able to oxidize phenols (and low redox potential dyes) at two catalytic sites, as shown by biphasic kinetics. A high efficiency site (with 2,6-dimethoxyphenol and p-hydroquinone catalytic efficiencies of ∼70 and ∼700 s(-1) mM(-1), respectively) was localized at the same exposed Trp-164 responsible for high redox potential substrate oxidation (as shown by activity loss in the W164S variant). The second site, characterized by low catalytic efficiency (∼3 and ∼50 s(-1) mM(-1) for 2,6-dimethoxyphenol and p-hydroquinone, respectively) was localized at the main heme access channel. Steady-state and transient-state kinetics for oxidation of phenols and dyes at the latter site were improved when side chains of residues forming the heme channel edge were removed in single and multiple variants. Among them, the E140G/K176G, E140G/P141G/K176G, and E140G/W164S/K176G variants attained catalytic efficiencies for oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) at the heme channel similar to those of the exposed tryptophan site. The heme channel enlargement shown by x-ray diffraction of the E140G, P141G, K176G, and E140G/K176G variants would allow a better substrate accommodation near the heme, as revealed by the up to 26-fold lower K(m) values (compared with native VP). The resulting interactions were shown by the x-ray structure of the E140G-guaiacol complex, which includes two H-bonds of the substrate with Arg-43 and Pro-139 in the distal heme pocket (at the end of the heme channel) and several hydrophobic interactions with other residues and the heme cofactor.

  1. Lanthanum chromite materials as potential symmetrical electrodes for Solid Oxide Fuel Cells

    Directory of Open Access Journals (Sweden)

    Ruiz-Morales, J. C.

    2007-08-01

    Full Text Available A commonly used interconnector material has been tested as electrode for a new concept of Solid Oxide Fuel Cell, where the same material could be used, simultaneously, as interconnector, anode and cathode. We have found that a typical substituted chromite, such as La0.7Ca0.3CrO3-δ (LCC can be considered a good candidate for such configuration, due to its high electronic conductivity in both reducing and oxidising conditions, and moderate catalytic properties for oxygen reduction and hydrogen oxidation. The symmetrical design renders performances of 100 mWcm-2 at 950ºC, using O2 and H2 as oxidant and fuel respectively. Performances exceeding 300 mWcm-2 can be predicted for a 100μm-thick YSZ electrolyte.

    Un material comúnmente utilizado como interconector ha sido probado como electrodo para un nuevo concepto de Pila de Combustible de Óxidos Sólido, en el cual el mismo material se utiliza, simultáneamente, como interconector, ánodo y cátodo. Hemos encontrado que una cromita típica como La0.7Ca0.3CrO3-δ (LCC puede ser considerada una buena candidata para dicha configuración, debido a sus altas conductividades eléctricas tanto en condiciones reductoras como oxidantes y una aceptable actividad catalítica para la reducción del oxígeno y la oxidación del hidrógeno. El diseño simétrico permite obtener rendimientos del orden de 100mWcm-2 a 950ºC, utilizando O2 e H2 como oxidante y combustible, respectivamente. Rendimientos que superan los 300mWcm-2 pueden predecirse para pilas con electrolitos de YSZ de 100 μm de grosor.

  2. Potential Role of Oxidative Stress in mediating the Effect of Hypergravity on the Developing CNS.

    Science.gov (United States)

    Sajdel-Sulkowska, E. M.; Nguon, K.; Sulkowski, Z. L.; Lipinski, B.

    The present studies will explore the mechanisms through which altered gravity affects the developing CNS We have previously shown that exposure to hypergravity during the perinatal period adversely impacts cerebellar structure and function Pregnant rat dams were exposed to 1 65 G on a 24-ft centrifuge at NASA-ARC from gestational day G 5 through giving birth Both dams and their offspring remained at 1 65 G until pups reached postnatal day P 21 Control rats were raised under identical conditions in stationary cages On P21 motor behavior as determined by performance on a rotorod was more negatively impacted in hypergravity-exposed HG male 39 5 than in HG female pups 29 1 The total number of Purkinje cells determined stereologically in cerebella isolated from a subset of P21 rats was decreased in both HG males and HG female pups but the correlation between Purkinje cell number and rotorod performance was more consistent in male pups The level of 3-nitrosotyrosine 3-NT an index of oxidative damage to proteins was determined by ELISA in cerebellar tissue derived from a separate subset of P21 rats The level of 3-NT was increased by 127 in HG males but only 42 in HG females These results suggest that the effect of altered gravity on the developing brain may be mediated by oxidative stress These results also suggest that the developing male CNS may be more sensitive to hypergravity-induced oxidative stress than the developing female CNS Supported by NIEHS grant ES11946-01

  3. KINETIC CONTROL OF OXIDATION STATE AT THERMODYNAMICALLY BUFFERED POTENTIALS IN SUBSURFACE WATERS

    Science.gov (United States)

    Dissolved oxygen (DO) and organic carbon (Corg) are among the highest- and lowest-potential reactants, respectively, of redox couples in natural waters. When DO and Corg are present in subsurface settings, other couples are drawn toward potentials imposed by them, generating a b...

  4. Lactosylated poly(ethylene oxide)-poly(propylene oxide) block copolymers for potential active targeting: synthesis and physicochemical and self-aggregation characterization

    Energy Technology Data Exchange (ETDEWEB)

    Cuestas, Maria L.; Glisoni, Romina J. [University of Buenos Aires, Group of Biomaterials and Nanotechnology for Improved Medicines (BIONIMED), Department of Pharmaceutical Technology, Faculty of Pharmacy and Biochemistry (Argentina); Mathet, Veronica L. [National Science Research Council (CONICET) (Argentina); Sosnik, Alejandro, E-mail: alesosnik@gmail.com [University of Buenos Aires, The Group of Biomaterials and Nanotechnology for Improved Medicines (BIONIMED), Department of Pharmaceutical Technology, Faculty of Pharmacy and Biochemistry (Argentina)

    2013-01-15

    Aiming to develop polymeric self-assembly nanocarriers with potential applications in active drug targeting to the liver, linear and branched poly(ethylene oxide)-poly(propylene oxide) amphiphiles were conjugated to lactobionic acid (LA), a disaccharide of galactose and gluconic acid, by the conventional Steglich esterification reaction. The conjugation was confirmed by ATR/FT-IR, {sup 1}H-NMR, and {sup 13}C-NMR spectroscopy. Elemental analysis and MALDI-TOF mass spectrometry were employed to elucidate the conjugation extent and the final molecular weight, respectively. The critical micellar concentration (CMC), the size and size distribution and zeta potential of the pristine and modified polymeric micelles under different conditions of pH and temperature were characterized by dynamic light scattering (DLS). Conjugation with LA favored the micellization process, leading to a decrease of the CMC with respect to the pristine counterpart, this phenomenon being independent of the pH and the temperature. At 37 Degree-Sign C, micelles made of pristine copolymers showed a monomodal size distribution between 12.8 and 24.4 nm. Conversely, LA-conjugated micelles showed a bimodal size pattern that comprised a main fraction of relatively small size (11.6-22.2 nm) and a second one with remarkably larger sizes of up to 941.4 nm. The former corresponded to single micelles, while the latter would indicate a secondary aggregation phenomenon. The spherical morphology of LA-micelles was visualized by transmission electron microscopy (TEM). Finally, to assess the ability of the LA-conjugated micelles to interact with lectin-like receptors, samples were incubated with concanavalin A at 37 Degree-Sign C and the size and size distribution were monitored by DLS. Findings indicated that regardless of the relatively weak affinity of this vegetal lectin for galactose, micelles underwent agglutination probably through the interaction of a secondary site in the lectin with the gluconic acid

  5. Ethyl nitrite is produced in the human stomach from dietary nitrate and ethanol, releasing nitric oxide at physiological pH: potential impact on gastric motility.

    Science.gov (United States)

    Rocha, Bárbara S; Gago, Bruno; Barbosa, Rui M; Cavaleiro, Carlos; Laranjinha, João

    2015-05-01

    Nitric oxide ((∙)NO), a ubiquitous molecule involved in a plethora of signaling pathways, is produced from dietary nitrate in the gut through the so-called nitrate-nitrite-NO pathway. In the stomach, nitrite derived from dietary nitrate triggers a network of chemical reactions targeting endogenous and exogenous biomolecules, thereby producing new compounds with physiological activity. The aim of this study was to ascertain whether compounds with physiological relevance are produced in the stomach upon consumption of nitrate- and ethanol-rich foods. Human volunteers consumed a serving of lettuce (source of nitrate) and alcoholic beverages (source of ethanol). After 15 min, samples of the gastric headspace were collected and ethyl nitrite was identified by GC-MS. Wistar rats were used to study the impact of ethyl nitrite on gastric smooth muscle relaxation at physiological pH. Nitrogen oxides, produced from nitrite in the stomach, induce nitrosation of ethanol from alcoholic beverages in the human stomach yielding ethyl nitrite. Ethyl nitrite, a potent vasodilator, is produced in vivo upon the consumption of lettuce with either red wine or whisky. Moreover, at physiological pH, ethyl nitrite induces gastric smooth muscle relaxation through a cGMP-dependent pathway. Overall, these results suggest that ethyl nitrite is produced in the gastric lumen and releases (∙)NO at physiological pH, which ultimately may have an impact on gastric motility. Systemic effects may also be expected if ethyl nitrite diffuses through the gastric mucosa reaching blood vessels, therefore operating as a (∙)NO carrier throughout the body. These data pinpoint posttranslational modifications as an underappreciated mechanism for the production of novel molecules with physiological impact locally in the gut and highlight the notion that diet may fuel compounds with the potential to modulate gastrointestinal welfare. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Oxidized Polyethylene Wax as a Potential Carbon Source for PHA Production

    Directory of Open Access Journals (Sweden)

    Iza Radecka

    2016-05-01

    Full Text Available We report on the ability of bacteria to produce biodegradable polyhydroxyalkanoates (PHA using oxidized polyethylene wax (O-PEW as a novel carbon source. The O-PEW was obtained in a process that used air or oxygen as an oxidizing agent. R. eutropha H16 was grown for 48 h in either tryptone soya broth (TSB or basal salts medium (BSM supplemented with O-PEW and monitored by viable counting. Study revealed that biomass and PHA production was higher in TSB supplemented with O-PEW compared with TSB only. The biopolymers obtained were preliminary characterized by nuclear magnetic resonance (NMR, gel permeation chromatography (GPC, differential scanning calorimetry (DSC, and thermogravimetric analysis (TGA. The detailed structural evaluation at the molecular level was performed by electrospray ionization tandem mass spectrometry (ESI-MS/MS. The study revealed that, when TSB was supplemented with O-PEW, bacteria produced PHA which contained 3-hydroxybutyrate and up to 3 mol % of 3-hydroxyvalerate and 3-hydroxyhexanoate co-monomeric units. The ESI-MS/MS enabled the PHA characterization when the content of 3-hydroxybutyrate was high and the appearance of other PHA repeating units was very low.

  7. Bio-mimicked atomic-layer-deposited iron oxide-based memristor with synaptic potentiation and depression functions

    Science.gov (United States)

    Wan, Xiang; Gao, Fei; Lian, Xiaojuan; Ji, Xincun; Hu, Ertao; He, Lin; Tong, Yi; Guo, Yufeng

    2018-06-01

    In this study, an iron oxide (FeO x )-based memristor was investigated for the realization of artificial synapses. An FeO x resistive switching layer was prepared by self-limiting atomic layer deposition (ALD). The movement of oxygen vacancies enabled the device to have history-dependent synaptic functions, which was further demonstrated by device modeling and simulation. Analog synaptic potentiation/depression in conductance was emulated by applying consecutive voltage pulses in the simulation. Our results suggest that the ALD FeO x -based memristor can be used as the basic building block for neural networks, neuromorphic systems, and brain-inspired computers.

  8. Mechanistic model to predict colostrum intake based on deuterium oxide dilution technique data and impact of gestation and prefarrowing diets on piglet intake and sow yield of colostrum

    DEFF Research Database (Denmark)

    Theil, Peter Kappel; Flummer, Christine; Hurley, W L

    2014-01-01

    The aims of the present study were to quantify colostrum intake (CI) of piglets using the D2O dilution technique, to develop a mechanistic model to predict CI, to compare these data with CI predicted by a previous empirical predictive model developed for bottle-fed piglets, and to study how...... composition of diets fed to gestating sows affected piglet CI, sow colostrum yield (CY), and colostrum composition. In total, 240 piglets from 40 litters were enriched with D2O. The CI measured by D2O from birth until 24 h after the birth of first-born piglet was on average 443 g (SD 151). Based on measured...... CI, a mechanistic model to predict CI was developed using piglet characteristics (24-h weight gain [WG; g], BW at birth [BWB; kg], and duration of CI [D; min]: CI, g = –106 + 2.26 WG + 200 BWB + 0.111 D – 1,414 WG/D + 0.0182 WG/BWB (R2 = 0.944). This model was used to predict the CI for all colostrum...

  9. The value of different vegetative indices (NDVI, GAI for the assessment of yield potential of pea (Pisum sativum L. at different growth stages and under varying management practices

    Directory of Open Access Journals (Sweden)

    Agnieszka Klimek-Kopyra

    2018-03-01

    Full Text Available This research evaluated the NDVI (normalized difference vegetation index and GAI (green area index in order to indicate the productivity and developmental effects of Rhizobium inoculants and microelement foliar fertilizer on pea crops. Two inoculants, Nitragina (a commercial inoculant and IUNG (a noncommercial inoculant gel and a foliar fertilizer (Photrel were studied over a 4-year period, 2009–2012. The cultivars chosen for the studies were characterized by different foliage types, namely a semileafless pea ‘Tarchalska’ and one with regular foliage, ‘Klif’. Foliar fertilizer significantly increased the length of the generative shoots and the number of fruiting nodes in comparison to the control, which in turn had a negative impact on the harvest index. Pea seed yield was highly dependent on the interaction between the years of growth and the microbial inoculant, and was greater for ‘Tarchalska’ (4.33 t ha−1. Presowing inoculation of seeds and foliar fertilization resulted in a significantly higher value of GAI at the flowering (3.91 and 3.81, respectively and maturity stages (4.82 and 4.77, respectively, whereas the value of NDVI was higher for these treatments only at the maturity stage (0.67 and 0.79, respectively. A significantly greater yield (5.0–5.4 t ha−1 was obtained after inoculation with IUNG during the dry years.

  10. Overexpression and purification of U24 from human herpesvirus type-6 in E. coli: unconventional use of oxidizing environments with a maltose binding protein-hexahistine dual tag to enhance membrane protein yield

    Directory of Open Access Journals (Sweden)

    Straus Suzana K

    2011-06-01

    Full Text Available Abstract Background Obtaining membrane proteins in sufficient quantity for biophysical study and biotechnological applications has been a difficult task. Use of the maltose binding protein/hexahistidine dual tag system with E.coli as an expression host is emerging as a high throughput method to enhance membrane protein yield, solubility, and purity, but fails to be effective for certain proteins. Optimizing the variables in this system to fine-tune for efficiency can ultimately be a daunting task. To identify factors critical to success in this expression system, we have selected to study U24, a novel membrane protein from Human Herpesvirus type-6 with potent immunosuppressive ability and a possible role in the pathogenesis of the disease multiple sclerosis. Results We expressed full-length U24 as a C-terminal fusion to a maltose binding protein/hexahistidine tag and examined the effects of temperature, growth medium type, cell strain type, oxidizing vs. reducing conditions and periplasmic vs. cytoplasmic expression location. Temperature appeared to have the greatest effect on yield; at 37°C full-length protein was either poorly expressed (periplasm or degraded (cytoplasm whereas at 18°C, expression was improved especially in the periplasm of C41(DE3 cells and in the cytoplasm of oxidizing Δtrx/Δgor mutant strains, Origami 2 and SHuffle. Expression of the fusion protein in these strains were estimated to be 3.2, 5.3 and 4.3 times greater, respectively, compared to commonly-used BL21(DE3 cells. We found that U24 is isolated with an intramolecular disulfide bond under these conditions, and we probed whether this disulfide bond was critical to high yield expression of full-length protein. Expression analysis of a C21SC37S cysteine-free mutant U24 demonstrated that this disulfide was not critical for full-length protein expression, but it is more likely that strained metabolic conditions favour factors which promote protein expression. This

  11. Potential of Lactobacillus plantarum CCFM639 in Protecting against Aluminum Toxicity Mediated by Intestinal Barrier Function and Oxidative Stress.

    Science.gov (United States)

    Yu, Leilei; Zhai, Qixiao; Tian, Fengwei; Liu, Xiaoming; Wang, Gang; Zhao, Jianxin; Zhang, Hao; Narbad, Arjan; Chen, Wei

    2016-12-02

    Aluminum (Al) is a ubiquitous metal that can seriously harm the health of animals and humans. In our previous study, we demonstrated that Lactobacillus plantarum CCFM639 can decrease Al burden in the tissues of mice by inhibiting intestinal Al absorption. The main aim of the present research was to investigate whether the protection by the strain is also associated with enhancement of the intestinal barrier, alleviation of oxidative stress and modulation of the inflammatory response. In an in vitro cell model, two protection modes (intervention and therapy) were examined and the results indicated that L. plantarum CCFM639 alleviated Al-induced cytotoxicity. In a mouse model, L. plantarum CCFM639 treatment was found to significantly alleviate oxidative stress in the intestinal tract, regulate the function of the intestinal mucosal immune system, restore the integrity of tight junction proteins and maintain intestinal permeability. These results suggest that in addition to Al sequestration, L. plantarum CCFM639 can also inhibit Al absorption by protecting the intestinal barrier, alleviating Al-induced oxidative stress and inflammatory response. Therefore, L. plantarum CCFM639 has the potential to be a dietary supplement ingredient that provides protection against Al-induced gut injury.

  12. Potential of Lactobacillus plantarum CCFM639 in Protecting against Aluminum Toxicity Mediated by Intestinal Barrier Function and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Leilei Yu

    2016-12-01

    Full Text Available Aluminum (Al is a ubiquitous metal that can seriously harm the health of animals and humans. In our previous study, we demonstrated that Lactobacillus plantarum CCFM639 can decrease Al burden in the tissues of mice by inhibiting intestinal Al absorption. The main aim of the present research was to investigate whether the protection by the strain is also associated with enhancement of the intestinal barrier, alleviation of oxidative stress and modulation of the inflammatory response. In an in vitro cell model, two protection modes (intervention and therapy were examined and the results indicated that L. plantarum CCFM639 alleviated Al-induced cytotoxicity. In a mouse model, L. plantarum CCFM639 treatment was found to significantly alleviate oxidative stress in the intestinal tract, regulate the function of the intestinal mucosal immune system, restore the integrity of tight junction proteins and maintain intestinal permeability. These results suggest that in addition to Al sequestration, L. plantarum CCFM639 can also inhibit Al absorption by protecting the intestinal barrier, alleviating Al-induced oxidative stress and inflammatory response. Therefore, L. plantarum CCFM639 has the potential to be a dietary supplement ingredient that provides protection against Al-induced gut injury.

  13. Antioxidant Potential of Spirulina platensis Mitigates Oxidative Stress and Reprotoxicity Induced by Sodium Arsenite in Male Rats

    Science.gov (United States)

    Bashandy, Samir A. E.; El Awdan, Sally A.; Ebaid, Hossam; Alhazza, Ibrahim M.

    2016-01-01

    The present study aimed to examine the protective role of Spirulina platensis (S. platensis) against arsenic-induced testicular oxidative damage in rats. Arsenic (in the form of NaAsO2 at a dose of 6.3 mg/kg body weight for 8 weeks) caused a significant accumulation of arsenic in testicular tissues as well as a decrease in the levels of testicular superoxide dismutase (SOD), catalase (CAT), reduced glutathione, and zinc. Moreover, it significantly decreased plasma testosterone, luteinizing hormone (LH), triiodothyronine (T3), and thyroxine (T4) levels and reduced sperm motility and sperm count. Arsenic (AS) led to a significant increase in testicular malondialdehyde (MDA), tumour necrosis factor alpha (TNF-α), nitric oxide (NO), and sperm abnormalities. S. platensis at a dose of 300 mg/kg was found to attenuate As-induced oxidative stress, testicular damage, and sperm abnormalities by its potent antioxidant activity. S. platensis may represent a potential therapeutic option to protect the testicular tissue from arsenic intoxication. PMID:26881036

  14. Copper atoms embedded in hexagonal boron nitride as potential catalysts for CO oxidation: A first-principles investigation

    KAUST Repository

    Liu, Xin

    2014-01-01

    We addressed the electronic structure of Cu atoms embedded in hexagonal boron nitride (h-BN) and their catalytic role in CO oxidation by first-principles-based calculations. We showed that Cu atoms prefer to bind directly with the localized defects on h-BN, which act as strong trapping sites for Cu atoms and inhibit their clustering. The strong binding of Cu atoms at boron vacancy also up-shifts the energy level of Cu-d states to the Fermi level and promotes the formation of peroxide-like intermediate. CO oxidation over Cu atoms embedded in h-BN would proceed through the Langmuir-Hinshelwood mechanism with the formation of a peroxide-like complex by reaction of coadsorbed CO and O2, with the dissociation of which the a CO2 molecule and an adsorbed O atom are formed. Then, the embedded Cu atom is regenerated by the reaction of another gaseous CO with the remnant O atom. The calculated energy barriers for the formation and dissociation of peroxide complex and regeneration of embedded Cu atoms are as low as 0.26, 0.11 and 0.03 eV, respectively, indicating the potential high catalytic performance of Cu atoms embedded in h-BN for low temperature CO oxidation. © the Partner Organisations 2014.

  15. Antioxidant Potential of Spirulina platensis Mitigates Oxidative Stress and Reprotoxicity Induced by Sodium Arsenite in Male Rats

    Directory of Open Access Journals (Sweden)

    Samir A. E. Bashandy

    2016-01-01

    Full Text Available The present study aimed to examine the protective role of Spirulina platensis (S. platensis against arsenic-induced testicular oxidative damage in rats. Arsenic (in the form of NaAsO2 at a dose of 6.3 mg/kg body weight for 8 weeks caused a significant accumulation of arsenic in testicular tissues as well as a decrease in the levels of testicular superoxide dismutase (SOD, catalase (CAT, reduced glutathione, and zinc. Moreover, it significantly decreased plasma testosterone, luteinizing hormone (LH, triiodothyronine (T3, and thyroxine (T4 levels and reduced sperm motility and sperm count. Arsenic (AS led to a significant increase in testicular malondialdehyde (MDA, tumour necrosis factor alpha (TNF-α, nitric oxide (NO, and sperm abnormalities. S. platensis at a dose of 300 mg/kg was found to attenuate As-induced oxidative stress, testicular damage, and sperm abnormalities by its potent antioxidant activity. S. platensis may represent a potential therapeutic option to protect the testicular tissue from arsenic intoxication.

  16. Chemical rules on the assessment of antioxidant potential in food and food additives aimed at reducing oxidative stress and neurodegeneration.

    Science.gov (United States)

    Franco, Rafael; Martínez-Pinilla, Eva

    2017-11-15

    Antioxidants (aOXs) enlarge the useful life of products consumed by humans. Life requires oxidation of glucose/fatty acids and, therefore, "antioxidant" becomes an oxymoron when trying to define benefits in organisms living in an oxygen-rich atmosphere. According to basic physico-chemical principles, the in vivo aOX potential of food supplements is negligible when compared with the main aOX molecules in the animal Kingdom: glucose and fatty acids. Thus, the aOX assumption to improve life-quality is misleading as oxidative stress and exacerbation occur when oxidant foods (e.g. fava beans) are consumed. Evolution produced potent detoxification mechanisms to handle these situations. When age/genetic/environmental factors negatively impact on detoxification mechanisms, nutrition helps on providing metabolites/precursors needed for boosting innate resources. Ambiguous techniques that attempt to measure in vivo aOX power, should give way to measuring the level of supplements and their metabolites in body fluids/tissues, and to measure the efficacy on antioxidant boosting REDOX pathways. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Evaluation of the potential of volatile organic compound (di-methyl benzene) removal using adsorption on natural minerals compared to commercial oxides

    Energy Technology Data Exchange (ETDEWEB)

    Zaitan, Hicham, E-mail: hicham.zaitan@usmba.ac.ma [Laboratory LCMC, Faculty of Sciences and Techniques, University Sidi Mohamed BenAbdellah, B.P. 2202, Fez (Morocco); Korrir, Abdelhamid; Chafik, Tarik [Laboratory LGCVR, Faculty of Sciences and Techniques, University Abdelmalek Essaadi, B.P. 416, Tangier (Morocco); Bianchi, Daniel [Institut de Recherche sur la Catalyse et l’Environnement de Lyon (IRCELYON), UMR 5256 CNRS, University Claude Bernard Lyon I, Bat. Chevreul, 43 Boulevard du 11 Novembre 1918, 69622 Villeurbanne (France)

    2013-11-15

    Highlights: • The adsorption of dMB on natural minerals and commercial oxides was evaluated. • The adsorption capacities were discussed considering the adsorbents cost and the bed size. • The adsorption capacity of bentonite is higher than other adsorbents. • Langmuir model provide best correlation of the experimental data. • The isotherms data allow determination of isosteric heat of adsorption. -- Abstract: This study is dedicated to the investigation of the potential of volatile organic compounds (VOC) adsorption over low cost natural minerals (bentonite and diatomite). The performances of these solids, in terms of adsorption/desorption properties, were compared to commercial adsorbents, such as silica, alumina and titanium dioxide. The solids were first characterized by different physico-chemical methods and di-methyl benzene (dMB) was selected as model VOC pollutant for the investigation of adsorptive characteristics. The experiments were carried out with a fixed bed reactor under dynamic conditions using Fourier Transform InfraRed spectrometer to measure the evolution of dMB concentrations in the gaseous stream at the outlet of the reactor. The measured breakthrough curves yields to adsorbed amounts at saturation that has been used to obtain adsorption isotherms. The latters were used for determination of the heat involved in the adsorption process and estimation of its values using the isosteric method. Furthermore, the performances of the studied materials were compared considering the adsorption efficiency/cost ratio.

  18. Evaluation of the potential of volatile organic compound (di-methyl benzene) removal using adsorption on natural minerals compared to commercial oxides

    International Nuclear Information System (INIS)

    Zaitan, Hicham; Korrir, Abdelhamid; Chafik, Tarik; Bianchi, Daniel

    2013-01-01

    Highlights: • The adsorption of dMB on natural minerals and commercial oxides was evaluated. • The adsorption capacities were discussed considering the adsorbents cost and the bed size. • The adsorption capacity of bentonite is higher than other adsorbents. • Langmuir model provide best correlation of the experimental data. • The isotherms data allow determination of isosteric heat of adsorption. -- Abstract: This study is dedicated to the investigation of the potential of volatile organic compounds (VOC) adsorption over low cost natural minerals (bentonite and diatomite). The performances of these solids, in terms of adsorption/desorption properties, were compared to commercial adsorbents, such as silica, alumina and titanium dioxide. The solids were first characterized by different physico-chemical methods and di-methyl benzene (dMB) was selected as model VOC pollutant for the investigation of adsorptive characteristics. The experiments were carried out with a fixed bed reactor under dynamic conditions using Fourier Transform InfraRed spectrometer to measure the evolution of dMB concentrations in the gaseous stream at the outlet of the reactor. The measured breakthrough curves yields to adsorbed amounts at saturation that has been used to obtain adsorption isotherms. The latters were used for determination of the heat involved in the adsorption process and estimation of its values using the isosteric method. Furthermore, the performances of the studied materials were compared considering the adsorption efficiency/cost ratio

  19. Breeding for Grass Seed Yield

    DEFF Research Database (Denmark)

    Boelt, Birte; Studer, Bruno

    2010-01-01

    Seed yield is a trait of major interest for many fodder and amenity grass species and has received increasing attention since seed multiplication is economically relevant for novel grass cultivars to compete in the commercial market. Although seed yield is a complex trait and affected...... by agricultural practices as well as environmental factors, traits related to seed production reveal considerable genetic variation, prerequisite for improvement by direct or indirect selection. This chapter first reports on the biological and physiological basics of the grass reproduction system, then highlights...... important aspects and components affecting the seed yield potential and the agronomic and environmental aspects affecting the utilization and realization of the seed yield potential. Finally, it discusses the potential of plant breeding to sustainably improve total seed yield in fodder and amenity grasses....

  20. Biological durability and oxidative potential of man-made vitreous fibres as compared to crocidolite asbestos fibres

    Energy Technology Data Exchange (ETDEWEB)

    Hippeli, S.; Dornisch, K.; Elstner, E.F. [Lehrstuhl fuer Phytopathologie, Technische Univ. Muenchen-Weihenstephan, Freising-Weihenstephan (Germany); Wiethege, T.; Mueller, K.M. [Berufsgenossenschaftliche Kliniken Bergmannsheil, Universitaetsklinik, Inst. fuer Pathologie, Bochum (Germany); Gillissen, A. [Medizinische Universitaetsklinik und Poliklinik II, Kardiologie, Pneumologie, Bonn (Germany)

    2001-08-01

    In this study we investigated relationships between redox properties and biodurability of crocidolite asbestos fibres and three different man-made vitreous fibres (MMVF): traditional stone wool fibres (MMVF 21), glass fibres (MMVF 11) and refractory ceramic fibres (RCF). Each fibre type was incubated up to 22 weeks in four different incubation media: gamble solution (GS) pH 5.0 and pH 7.4, representing blood plasma without proteins, and surfactant-like solution (SLS) pH 5.0 and pH 7.4. During incubation time aliquots of incubation mixtures were removed and analysed in a biochemical model reaction, mimicking activated phagocytes. In addition, changes of fibre morphology and chemical composition were examined using SEM- and EDX-technology. In the presence of crocidolite asbestos fibres and MMVF 21 the formation of OH-radicals according to the Haber-Weiss sequence could be demonstrated, whereas MMVF 11 and RCF showed no reactivity. Crocidolite asbestos fibres exhibited a significant higher activity compared with the stone wool fibres at the onset of incubation. The oxidative capacities of these fibre types were shown to depend on both specific surface area and iron content. The oxidative potentials of crocidolite asbestos fibres as well as MMVF 21 were not constant during incubation over several weeks in each incubation medium. The reactivities showed sinoidal curves including reactivities much higher than those at the onset of incubation time. These irregular changes of oxidative capacity may be explained by changes of the redox state of fibre surface-complexed iron. Furthermore our results showed clear differences between incubation of fibres in GS and SLS, respectively, indicating that phospholipids play an important part in fibre dissolution behaviour and oxidative reactivity. (orig.)

  1. Evaluation of haloalkaliphilic sulfur-oxidizing microorganisms with potential application in the effluent treatment of the petroleum industry.

    Science.gov (United States)

    Olguín-Lora, P; Le Borgne, S; Castorena-Cortés, G; Roldán-Carrillo, T; Zapata-Peñasco, I; Reyes-Avila, J; Alcántara-Pérez, S

    2011-02-01

    Haloalkaliphilic sulfur-oxidizing mixed cultures for the treatment of alkaline-saline effluents containing sulfide were characterized and evaluated. The mixed cultures (IMP-PB, IMP-XO and IMP-TL) were obtained from Mexican alkaline soils collected in Puebla (PB), Xochimilco (XO) and Tlahuac (TL), respectively. The Ribosomal Intergenic Spacer Analysis (RISA) revealed bacteria related to Thioalkalibacterium and Thioalkalivibrio in IMP-XO and IMP-PB mixed cultures. Halomonas strains were detected in IMP-XO and IMP-TL. In addition, an uncultured Bacteroides bacterium was present in IMP-TL. Mixed cultures were evaluated at different pH and NaCl concentrations at 30°C. IMP-PB and IMP-TL expressed thiosulfate-oxidizing activity in the 7.5-10.5 pH range, whereas IMP-XO presented its maximal activity with 19.0 mg O₂ g (protein)⁻¹ min⁻¹, at pH 10.6; it was not affected by NaCl concentrations up to 1.7 M. In continuous culture, IMP-XO showed a growth rate of 15 day⁻¹, productivity of 433.4 mg(protein) l⁻¹ day⁻¹ and haloalkaliphilic sulfur-oxidizing activity was also detected up to 170 mM by means of N-methyl-diethanolamine (MDEA). Saline-alkaline soil samples are potential sources of haloalkaliphilic sulfur-oxidizing bacteria and the mixed cultures could be applied in the treatment of inorganic sulfur compounds in petroleum industry effluents under alkaline-saline conditions.

  2. Sowing time on Soybean yield potential in Uberlândia-MGÉpoca de semeadura no Potencial produtivo de Soja em Uberlândia-MG

    Directory of Open Access Journals (Sweden)

    Cristina Divina Lemes Hamawaki

    2011-12-01

    Full Text Available The work was done in Uberlândia (MG to evaluate the performance of seven soybeans cultivars sowed in four different times: October 30th, November 15th, December 14th and 31st during the 2001/2002 season. The cultivars utilized were: DM-118 early-maturing, DM-247, DM-Victoria, DM-339, medium late cycle and DM-309, DM-98C81 and DM-Noble cycle Late. The statistical design was a randomized blocks in a factorial scheme (7 cultivars x 4 times with three replications. The evaluated characteristics were: yield, number of days for flowering, number of days for maturing, plant height, first bean height and plant laying. For the most evaluated cultivars, sowing beyond December 14th in Uberlandia region presented yield losses for earlier cultivars as DM-118 as well for the later ones as DM Vitória, compared to sowing in 30th October. The time for flowering and maturing and plant height had effect on the yield.O trabalho foi feito em Uberlândia, com o objetivo de avaliar o comportamento de sete cultivares de soja em quatro épocas distintas de semeadura: 30 de Outubro, 15 de Novembro, 14 e 31 de Dezembro, na safra 2001/02. As cultivares utilizadas foram: DM-118 de ciclo precoce, DM-247, DM-Vitória, DM-339, de ciclo semitardio e DM-309, DM-98C81 e DM-Nobre de ciclo tardio. O delineamento utilizado foi o de blocos casualizados em esquema fatorial (7 cultivares x 4 épocas com três repetições. As características avaliadas foram: produtividade, número de dias para floração e maturação, altura de plantas na maturação, inserção da primeira vagem e acamamento. Para a maioria das cultivares, a semeadura realizada a partir de 14 de dezembro na região de Uberlândia provocou queda na produtividade, tanto para as cultivares mais precoces quanto para mais tardia, DM Vitória, quando comparada a semeadura em 30 de outubro. O período para o florescimento, maturação e a altura de plantas interferiram na produtividade. Há decréscimo de altura de

  3. Protein-functionalized magnetic iron oxide nanoparticles: time efficient potential-water treatment

    International Nuclear Information System (INIS)

    Okoli, Chuka; Boutonnet, Magali; Järås, Sven; Rajarao-Kuttuva, Gunaratna

    2012-01-01

    Recent advances in nanoscience suggest that the existing issues involving water quality could be resolved or greatly improved using nanomaterials, especially magnetic iron oxide nanoparticles. Magnetic nanoparticles have been synthesized for the development and use, in association with natural coagulant protein for water treatment. The nanoparticles size, morphology, structure, and magnetic properties were characterized by transmission electron microscope, X-ray diffraction, and superconducting quantum interference device magnetometry. Purified Moringa oleifera protein was attached onto microemulsions-prepared magnetic iron oxide nanoparticles (ME-MION) to form stable protein-functionalized magnetic nanoparticles (PMO+ME-MION). The turbidity removal efficiency in both synthetic and surface water samples were investigated and compared with the commonly used synthetic coagulant (alum) as well as PMO. More than 90 % turbidity could be removed from the surface waters within 12 min by magnetic separation of PMO+ME-MION; whereas gravimetrically, 70 % removal in high and low turbid waters can be achieved within 60 min. In contrast, alum requires 180 min to reduce the turbidity of low turbid water sample. These data support the advantage of separation with external magnetic field (magnetophoresis) over gravitational force. Time kinetics studies show a significant enhancement in ME-MION efficiency after binding with PMO implying the availability of large surface of the ME-MION. The coagulated particles (impurities) can be removed from PMO+ME-MION by washing with mild detergent or cleaning solution. To our knowledge, this is the first report on surface water turbidity removal using protein-functionalized magnetic nanoparticle.

  4. Protein-functionalized magnetic iron oxide nanoparticles: time efficient potential-water treatment

    Energy Technology Data Exchange (ETDEWEB)

    Okoli, Chuka [Royal Institute of Technology (KTH), Environmental Microbiology (Sweden); Boutonnet, Magali; Jaeras, Sven [Royal Institute of Technology (KTH), Chemical Technology (Sweden); Rajarao-Kuttuva, Gunaratna, E-mail: gkr@kth.se [Royal Institute of Technology (KTH), Environmental Microbiology (Sweden)

    2012-10-15

    Recent advances in nanoscience suggest that the existing issues involving water quality could be resolved or greatly improved using nanomaterials, especially magnetic iron oxide nanoparticles. Magnetic nanoparticles have been synthesized for the development and use, in association with natural coagulant protein for water treatment. The nanoparticles size, morphology, structure, and magnetic properties were characterized by transmission electron microscope, X-ray diffraction, and superconducting quantum interference device magnetometry. Purified Moringa oleifera protein was attached onto microemulsions-prepared magnetic iron oxide nanoparticles (ME-MION) to form stable protein-functionalized magnetic nanoparticles (PMO+ME-MION). The turbidity removal efficiency in both synthetic and surface water samples were investigated and compared with the commonly used synthetic coagulant (alum) as well as PMO. More than 90 % turbidity could be removed from the surface waters within 12 min by magnetic separation of PMO+ME-MION; whereas gravimetrically, 70 % removal in high and low turbid waters can be achieved within 60 min. In contrast, alum requires 180 min to reduce the turbidity of low turbid water sample. These data support the advantage of separation with external magnetic field (magnetophoresis) over gravitational force. Time kinetics studies show a significant enhancement in ME-MION efficiency after binding with PMO implying the availability of large surface of the ME-MION. The coagulated particles (impurities) can be removed from PMO+ME-MION by washing with mild detergent or cleaning solution. To our knowledge, this is the first report on surface water turbidity removal using protein-functionalized magnetic nanoparticle.

  5. Pure and Oxidized Copper Materials as Potential Antimicrobial Surfaces for Spaceflight Activities

    Science.gov (United States)

    Hahn, C.; Hans, M.; Hein, C.; Mancinelli, R. L.; Mücklich, F.; Wirth, R.; Rettberg, P.; Hellweg, C. E.; Moeller, R.

    2017-12-01

    Microbial biofilms can lead to persistent infections and degrade a variety of materials, and they are notorious for their persistence and resistance to eradication. During long-duration space missions, microbial biofilms present a danger to crew health and spacecraft integrity. The use of antimicrobial surfaces provides an alternative strategy for inhibiting microbial growth and biofilm formation to conventional cleaning procedures and the use of disinfectants. Antimicrobial surfaces contain organic or inorganic compounds, such as antimicrobial peptides or copper and silver, that inhibit microbial growth. The efficacy of wetted oxidized copper layers and pure copper surfaces as antimicrobial agents was tested by applying cultures of Escherichia coli and Staphylococcus cohnii to these metallic surfaces. Stainless steel surfaces were used as non-inhibitory control surfaces. The production of reactive oxygen species and membrane damage increased rapidly within 1 h of exposure on pure copper surfaces, but the effect on cell survival was negligible even after 2 h of exposure. However, longer exposure times of up to 4 h led to a rapid decrease in cell survival, whereby the survival of cells was additionally dependent on the exposed cell density. Finally, the release of metal ions was determined to identify a possible correlation between copper ions in suspension and cell survival. These measurements indicated a steady increase of free copper ions, which were released indirectly by cells presumably through excreted complexing agents. These data indicate that the application of antimicrobial surfaces in spaceflight facilities could improve crew health and mitigate material damage caused by microbial contamination and biofilm formation. Furthermore, the results of this study indicate that cuprous oxide layers were superior to pure copper surfaces related to the antimicrobial effect and that cell density is a significant factor that influences the time dependence of

  6. Protein-functionalized magnetic iron oxide nanoparticles: time efficient potential-water treatment

    Science.gov (United States)

    Okoli, Chuka; Boutonnet, Magali; Järås, Sven; Rajarao-Kuttuva, Gunaratna

    2012-10-01

    Recent advances in nanoscience suggest that the existing issues involving water quality could be resolved or greatly improved using nanomaterials, especially magnetic iron oxide nanoparticles. Magnetic nanoparticles have been synthesized for the development and use, in association with natural coagulant protein for water treatment. The nanoparticles size, morphology, structure, and magnetic properties were characterized by transmission electron microscope, X-ray diffraction, and superconducting quantum interference device magnetometry. Purified Moringa oleifera protein was attached onto microemulsions-prepared magnetic iron oxide nanoparticles (ME-MION) to form stable protein-functionalized magnetic nanoparticles (PMO+ME-MION). The turbidity removal efficiency in both synthetic and surface water samples were investigated and compared with the commonly used synthetic coagulant (alum) as well as PMO. More than 90 % turbidity could be removed from the surface waters within 12 min by magnetic separation of PMO+ME-MION; whereas gravimetrically, 70 % removal in high and low turbid waters can be achieved within 60 min. In contrast, alum requires 180 min to reduce the turbidity of low turbid water sample. These data support the advantage of separation with external magnetic field (magnetophoresis) over gravitational force. Time kinetics studies show a significant enhancement in ME-MION efficiency after binding with PMO implying the availability of large surface of the ME-MION. The coagulated particles (impurities) can be removed from PMO+ME-MION by washing with mild detergent or cleaning solution. To our knowledge, this is the first report on surface water turbidity removal using protein-functionalized magnetic nanoparticle.

  7. Change of the work function and potential barrier transparency of W(100) and GaAs(110) single crystals during removing the inherent surface oxide layer

    International Nuclear Information System (INIS)

    Asalkhanov, Yu.I.; Saneev, Eh.L.

    2002-01-01

    Changes of current voltage characteristics of slow monoenergetic electron beam through the surfaces of W(100) and GaAs(100) single crystals have been measured in the process of surface oxide layers elimination. It is shown that work function is decreased and transparency coefficient of surface potential barrier is increased under increasing the temperature of vacuum annealing. Peculiarities of surface potential change under oxide layer elimination in metals and semiconductors are discussed [ru

  8. Rye and Wheat Bran Extracts Isolated with Pressurized Solvents Increase Oxidative Stability and Antioxidant Potential of Beef Meat Hamburgers.

    Science.gov (United States)

    Šulniūtė, Vaida; Jaime, Isabel; Rovira, Jordi; Venskutonis, Petras Rimantas

    2016-02-01

    Rye and wheat bran extracts containing phenolic compounds and demonstrating high DPPH• (2,2-diphenyl-1-picrylhydrazyl), ABTS(•+) (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) scavenging and oxygen radical absorbance capacities (ORAC) were tested in beef hamburgers as possible functional ingredients. Bran extracts significantly increased the indicators of antioxidant potential of meat products and their global antioxidant response (GAR) during physiological in vitro digestion. The extracts also inhibited the formation of oxidation products, hexanal and malondialdehyde, of hamburgers during their storage; however, they did not have significant effect on the growth of microorganisms. Hamburgers with 0.8% wheat bran extract demonstrated the highest antioxidant potential. Some effects of bran extracts on other quality characteristics such as pH, color, formation of metmyoglobin were also observed, however, these effects did not have negative influence on the overall sensory evaluation score of hamburgers. Consequently, the use of bran extracts in meat products may be considered as promising means of increasing oxidative product stability and enriching with functional ingredients which might possess health benefits. © 2016 Institute of Food Technologists®

  9. Mechanistic model to predict colostrum intake based on deuterium oxide dilution technique data and impact of gestation and prefarrowing diets on piglet intake and sow yield of colostrum.

    Science.gov (United States)

    Theil, P K; Flummer, C; Hurley, W L; Kristensen, N B; Labouriau, R L; Sørensen, M T

    2014-12-01

    The aims of the present study were to quantify colostrum intake (CI) of piglets using the D2O dilution technique, to develop a mechanistic model to predict CI, to compare these data with CI predicted by a previous empirical predictive model developed for bottle-fed piglets, and to study how composition of diets fed to gestating sows affected piglet CI, sow colostrum yield (CY), and colostrum composition. In total, 240 piglets from 40 litters were enriched with D2O. The CI measured by D2O from birth until 24 h after the birth of first-born piglet was on average 443 g (SD 151). Based on measured CI, a mechanistic model to predict CI was developed using piglet characteristics (24-h weight gain [WG; g], BW at birth [BWB; kg], and duration of CI [D; min]: CI, g=-106+2.26 WG+200 BWB+0.111 D-1,414 WG/D+0.0182 WG/BWB (R2=0.944). This model was used to predict the CI for all colostrum suckling piglets within the 40 litters (n=500, mean=437 g, SD=153 g) and was compared with the CI predicted by a previous empirical predictive model (mean=305 g, SD=140 g). The previous empirical model underestimated the CI by 30% compared with that obtained by the new mechanistic model. The sows were fed 1 of 4 gestation diets (n=10 per diet) based on different fiber sources (low fiber [17%] or potato pulp, pectin residue, or sugarbeet pulp [32 to 40%]) from mating until d 108 of gestation. From d 108 of gestation until parturition, sows were fed 1 of 5 prefarrowing diets (n=8 per diet) varying in supplemented fat (3% animal fat, 8% coconut oil, 8% sunflower oil, 8% fish oil, or 4% fish oil+4% octanoic acid). Sows fed diets with pectin residue or sugarbeet pulp during gestation produced colostrum with lower protein, fat, DM, and energy concentrations and higher lactose concentrations, and their piglets had greater CI as compared with sows fed potato pulp or the low-fiber diet (Pcoconut oil decreased lactose and increased DM concentrations of colostrum compared with other prefarrowing diets (P

  10. Spectroelectrochemical properties of ultra-thin indium tin oxide films under electric potential modulation

    Energy Technology Data Exchange (ETDEWEB)

    Han, Xue, E-mail: x0han004@louisville.edu; Mendes, Sergio B., E-mail: sbmend01@louisville.edu

    2016-03-31

    In this work, the spectroscopic properties of ultra-thin ITO films are characterized under an applied electric potential modulation. To detect minute spectroscopic features, the ultra-thin ITO film was coated over an extremely sensitive single-mode integrated optical waveguide, which provided a long pathlength with more than adequate sensitivity for optical interrogation of the ultra-thin film. Experimental configurations with broadband light and several laser lines at different modulation schemes of an applied electric potential were utilized to elucidate the nature of intrinsic changes. The imaginary component of the refractive index (absorption coefficient) of the ultra-thin ITO film is unequivocally shown to have a dependence on the applied potential and the profile of this dependence changes substantially even for wavelengths inside a small spectral window (500–600 nm). The characterization technique and the data reported here can be crucial to several applications of the ITO material as a transparent conductive electrode, as for example in spectroelectrochemical investigations of surface-confined redox species. - Highlights: • Optical waveguides are applied for spectroscopic investigations of ultra-thin films. • Ultra-thin ITO films in aqueous environment are studied under potential modulation. • Unique spectroscopic features of ultra-thin ITO films are unambiguously observed.

  11. Potential seaweed-based food ingredients to inhibit lipid oxidation in fish-oil-enriched mayonnaise

    DEFF Research Database (Denmark)

    Honold, Philipp; Jacobsen, Charlotte; Jónsdóttir, Rósa

    2016-01-01

    Brown seaweed Fucus vesiculosus has a high potential as a source of natural antioxidants due to a high diversity of bioactive compounds in its composition. In this study, four extracts were characterized with respect to composition of bioactive compounds, in vitro antioxidant properties and their...

  12. Heterogeneity of Systemic Oxidative Stress Profiles in COPD: A Potential Role of Gender

    Directory of Open Access Journals (Sweden)

    Jonathan Maury

    2015-01-01

    Full Text Available Oxidative stress (OS plays a key role in the muscle impairment and exercise capacity of COPD patients. However, the literature reveals that systemic OS markers show great heterogeneity, which may hinder the prescription of effective antioxidant supplementation. This study therefore aimed to identify OS markers imbalance of COPD patients, relative to validated normal reference values, and to investigate the possibility of systemic OS profiles. We measured systemic enzymatic/nonenzymatic antioxidant and lipid peroxidation (LP levels in 54 stable COPD patients referred for a rehabilitation program. The main systemic antioxidant deficits in these patients concerned vitamins and trace elements. Fully 89% of the COPD patients showed a systemic antioxidant imbalance which may have caused the elevated systemic LP levels in 69% of them. Interestingly, two patient profiles (clusters 3 and 4 had a more elevated increase in LP combined with increased copper and/or decreased vitamin C, GSH, and GPx. Further analysis revealed that the systemic LP level was higher in COPD women and associated with exercise capacity. Our present data therefore support future supplementations with antioxidant vitamins and trace elements to improve exercise capacity, but COPD patients will probably show different positive responses.

  13. Toxicity potential of residual ethylene oxide on fresh or frozen embryos maintained in plastic straws.

    Science.gov (United States)

    Schiewe, M C; Schmidt, P M; Pontbriand, D; Wildt, D E

    1988-01-01

    The toxic effects of residual ethylene oxide (EtO), a frequently used gas-sterilant, on embryos either frozen for long-term purposes or stored acutely for 30 min to 9 hr in a fresh condition in 0.25-ml straw containers were evaluated. In Experiment 1, fresh embryos were frozen (using conventional technology) in straws previously aerated for 0 hr to 8 mo after EtO sterilization. With the exception of the 8-mo group in which survival and quality ratings were depressed, embryo viability was not affected significantly by short-term prefreeze and post-thaw exposure to EtO residues. Experiment 2 was conducted to analyze the influence of prefreeze exposure to EtO residues on embryo development in vitro for embryos temporarily stored in previously sterilized straws aerated for different intervals. Compared to non-EtO-sterilized control straws, the development, quality, and viability of embryos exposed to EtO-treated straws were compromised (p less than 0.05) as the aeration interval decreased and the exposure interval increased. The combined results of both experiments indicate that EtO-treated straws can be used to cryopreserve gametes efficiently, but only if the aeration interval is greater than or equal to 72 hr and the prefreeze duration of exposure is less than or equal to 3 hr.

  14. Reduction of graphene oxide nanosheets by natural beta carotene and its potential use as supercapacitor electrode

    Directory of Open Access Journals (Sweden)

    Rubaiyi M. Zaid

    2015-07-01

    Full Text Available A green, non-toxic and eco-friendly approach for the reduction of graphene oxide (GO nanosheets using natural β-carotene is reported. The FTIR spectroscopy and thermogravimetric analyses reveal the oxygen scavenging property of β-carotene successfully removes oxygen functionalities on GO nanosheets. Complete GO reduction is achieved within 16 h with 10 mM β-carotene as confirmed by the UV spectroscopy results. The high resolution transmission electron microscopy images provide clear evidence for the formation of few layers of graphene nanosheets. Furthermore, the mechanism of GO reduction by β-carotene has been proposed in this study. The electrochemical testing shows good charge storage properties of β-carotene reduced GO (142 F/g at 10 mV/s; 149 F/g at 1 A/g in Na2SO4, with stable cycling (89% for up to 1000 cycles. The findings suggest the reduction of GO nanosheets by β-carotene is a suitable approach in producing graphene nanosheets for supercapacitor electrode.

  15. Osteogenic potential of a novel microarc oxidized coating formed on Ti6Al4V alloys

    Science.gov (United States)

    Wang, Yaping; Lou, Jin; Zeng, Lilan; Xiang, Junhuai; Zhang, Shufang; Wang, Jun; Xiong, Fucheng; Li, Chenglin; Zhao, Ying; Zhang, Rongfa

    2017-08-01

    In order to improve the biocompatibility, Ti6Al4V alloys are processed by micro arc oxidation (MAO) in a novel electrolyte of phytic acid, a natural organic phosphorus-containing matter. The MAO coatings were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS). The cytocompatibility of Ti6A14V alloys before and after MAO were comprehensively evaluated. The results showed that the fabricated MAO coatings were composed of rutile, anatase, TiP2O7 as well as some OH- groups, exhibiting the excellent hydrophilicity and a porous structure with small micro pores. No cytotoxicity towards MC3T3-E1cells was observed in this study. In particular, MAO treated Ti6Al4V alloys presented comparable cell adhesion and proliferation as well as significantly enhanced alkaline phosphatase activity, extracellular matrix (ECM) mineralization and collagen secretion in comparison with the untreated control. The results suggest that the Ti6Al4V alloys treated by MAO in phytic acid can be used as implants for orthopaedic applications, providing a simple and practical method to widen clinical acceptance of titanium alloys.

  16. Evaluating the potential impact of proton carriers on syntrophic propionate oxidation

    Science.gov (United States)

    Juste-Poinapen, Natacha M. S.; Turner, Mark S.; Rabaey, Korneel; Virdis, Bernardino; Batstone, Damien J.

    2015-12-01

    Anaerobic propionic acid degradation relies on interspecies electron transfer (IET) between propionate oxidisers and electron acceptor microorganisms, via either molecular hydrogen, formate or direct transfers. We evaluated the possibility of stimulating direct IET, hence enhancing propionate oxidation, by increasing availability of proton carriers to decrease solution resistance and reduce pH gradients. Phosphate was used as a proton carrying anion, and chloride as control ion together with potassium as counter ion. Propionic acid consumption in anaerobic granules was assessed in a square factorial design with ratios (1:0, 2:1, 1:1, 1:2 and 0:1) of total phosphate (TP) to Cl-, at 1X, 10X, and 30X native conductivity (1.5 mS.cm-1). Maximum specific uptake rate, half saturation, and time delay were estimated using model-based analysis. Community profiles were analysed by fluorescent in situ hybridisation and 16S rRNA gene pyrosequencing. The strongest performance was at balanced (1:1) ratios at 10X conductivity where presumptive propionate oxidisers namely Syntrophobacter and Candidatus Cloacamonas were more abundant. There was a shift from Methanobacteriales at high phosphate, to Methanosaeta at low TP:Cl ratios and low conductivity. A lack of response to TP, and low percentage of presumptive electroactive organisms suggested that DIET was not favoured under the current experimental conditions.

  17. Butachlor induced dissipation of mitochondrial membrane potential, oxidative DNA damage and necrosis in human peripheral blood mononuclear cells

    International Nuclear Information System (INIS)

    Dwivedi, Sourabh; Saquib, Quaiser; Al-Khedhairy, Abdulaziz A.; Musarrat, Javed

    2012-01-01

    Highlights: ► Butachlor exhibited strong binding affinity with DNA and produced 8-oxodG adducts. ► Butachlor induced DNA strand breaks and micronuclei formation in PBMN cells. ► Butachlor induced ROS and dissipation of mitochondrial membrane potential in cells. ► Butachlor resulted in cell cycle arrest and eventually caused cellular necrosis. -- Abstract: Butachlor is a systemic herbicide widely applied on rice, tea, wheat, beans and other crops; however, it concurrently exerts toxic effects on beneficial organisms like earthworms, aquatic invertebrates and other non-target animals including humans. Owing to the associated risk to humans, this chloroacetanilide class of herbicide was investigated with the aim to assess its potential for the (i) interaction with DNA, (ii) mitochondria membrane damage and DNA strand breaks and (iii) cell cycle arrest and necrosis in butachlor treated human peripheral blood mononuclear (PBMN) cells. Fluorescence quenching data revealed the binding constant (Ka = 1.2 × 10 4 M −1 ) and binding capacity (n = 1.02) of butachlor with ctDNA. The oxidative potential of butachlor was ascertained based on its capacity of inducing reactive oxygen species (ROS) and substantial amounts of promutagenic 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) adducts in DNA. Also, the discernible butachlor dose-dependent reduction in fluorescence intensity of a cationic dye rhodamine (Rh-123) and increased fluorescence intensity of 2′,7′-dichlorodihydro fluorescein diacetate (DCFH-DA) in treated cells signifies decreased mitochondrial membrane potential (ΔΨm) due to intracellular ROS generation. The comet data revealed significantly greater Olive tail moment (OTM) values in butachlor treated PBMN cells vs untreated and DMSO controls. Treatment of cultured PBMN cells for 24 h resulted in significantly increased number of binucleated micronucleated (BNMN) cells with a dose dependent reduction in the nuclear division index (NDI). The flow

  18. Oxidation of naturally reduced uranium in aquifer sediments by dissolved oxygen and its potential significance to uranium plume persistence

    Science.gov (United States)

    Davis, J. A.; Smith, R. L.; Bohlke, J. K.; Jemison, N.; Xiang, H.; Repert, D. A.; Yuan, X.; Williams, K. H.

    2015-12-01

    The occurrence of naturally reduced zones is common in alluvial aquifers in the western U.S.A. due to the burial of woody debris in flood plains. Such reduced zones are usually heterogeneously dispersed in these aquifers and characterized by high concentrations of organic carbon, reduced mineral phases, and reduced forms of metals, including uranium(IV). The persistence of high concentrations of dissolved uranium(VI) at uranium-contaminated aquifers on the Colorado Plateau has been attributed to slow oxidation of insoluble uranium(IV) mineral phases found in association with these reducing zones, although there is little understanding of the relative importance of various potential oxidants. Four field experiments were conducted within an alluvial aquifer adjacent to the Colorado River near Rifle, CO, wherein groundwater associated with the naturally reduced zones was pumped into a gas-impermeable tank, mixed with a conservative tracer (Br-), bubbled with a gas phase composed of 97% O2 and 3% CO2, and then returned to the subsurface in the same well from which it was withdrawn. Within minutes of re-injection of the oxygenated groundwater, dissolved uranium(VI) concentrations increased from less than 1 μM to greater than 2.5 μM, demonstrating that oxygen can be an important oxidant for uranium in such field systems if supplied to the naturally reduced zones. Dissolved Fe(II) concentrations decreased to the detection limit, but increases in sulfate could not be detected due to high background concentrations. Changes in nitrogen species concentrations were variable. The results contrast with other laboratory and field results in which oxygen was introduced to systems containing high concentrations of mackinawite (FeS), rather than the more crystalline iron sulfides found in aged, naturally reduced zones. The flux of oxygen to the naturally reduced zones in the alluvial aquifers occurs mainly through interactions between groundwater and gas phases at the water table

  19. Yield trends and yield gap analysis of major crops in the world

    NARCIS (Netherlands)

    Hengsdijk, H.; Langeveld, J.W.A.

    2009-01-01

    This study aims to quantify the gap between current and potential yields of major crops in the world, and the production constraints th