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Sample records for iron fertilization simulations

  1. Ocean iron fertilization

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.; Smetacek, V.

    In 2009 and 2010, an Indo-German scientific expedition dusted the ocean with iron to stimulate the biological pump that captures atmosphereic carbon dioxide. Two onboard scientists tell the story of this controversial project. Besides raising...

  2. Iron Fertilization of the Southern Ocean: Regional Simulation and Analysis of C-Sequestration in the Ross Sea

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Arrigo

    2012-03-13

    A modified version of the dynamic 3-dimensional mesoscale Coupled Ice, Atmosphere, and Ocean model (CIAO) of the Ross Sea ecosystem has been used to simulate the impact of environmental perturbations upon primary production and biogenic CO2 uptake. The Ross Sea supports two taxonomically, and spatially distinct phytoplankton populations; the haptophyte Phaeocystis antarctica and diatoms. Nutrient utilization ratios predict that P. antarctica and diatoms will be driven to nitrate and phosphate limitation, respectively. Model and field data have confirmed that the Ross Sea is iron limited with only two-thirds of the macronutrients consumed by the phytoplankton by the end of the growing season. In this study, the CIAO model was improved to simulate a third macronutrient (phosphate), dissolved organic carbon, air-sea gas exchange, and the carbonate system. This enabled us to effectively model pCO2 and subsequently oceanic CO2 uptake via gas exchange, allowing investigations into the affect of alleviating iron limitation on both pCO2 and nutrient drawdown.

  3. Efficiency of small scale carbon mitigation by patch iron fertilization

    Science.gov (United States)

    Sarmiento, J. L.; Slater, R. D.; Dunne, J.; Gnanadesikan, A.; Hiscock, M. R.

    2010-11-01

    While nutrient depletion scenarios have long shown that the high-latitude High Nutrient Low Chlorophyll (HNLC) regions are the most effective for sequestering atmospheric carbon dioxide, recent simulations with prognostic biogeochemical models have suggested that only a fraction of the potential drawdown can be realized. We use a global ocean biogeochemical general circulation model developed at GFDL and Princeton to examine this and related issues. We fertilize two patches in the North and Equatorial Pacific, and two additional patches in the Southern Ocean HNLC region north of the biogeochemical divide and in the Ross Sea south of the biogeochemical divide. We evaluate the simulations using observations from both artificial and natural iron fertilization experiments at nearby locations. We obtain by far the greatest response to iron fertilization at the Ross Sea site, where sea ice prevents escape of sequestered CO2 during the wintertime, and the CO2 removed from the surface ocean by the biological pump is carried into the deep ocean by the circulation. As a consequence, CO2 remains sequestered on century time-scales and the efficiency of fertilization remains almost constant no matter how frequently iron is applied as long as it is confined to the growing season. The second most efficient site is in the Southern Ocean. The North Pacific site has lower initial nutrients and thus a lower efficiency. Fertilization of the Equatorial Pacific leads to an expansion of the suboxic zone and a striking increase in denitrification that causes a sharp reduction in overall surface biological export production and CO2 uptake. The impacts on the oxygen distribution and surface biological export are less prominent at other sites, but nevertheless still a source of concern. The century time scale retention of iron in this model greatly increases the long-term biological response to iron addition as compared with simulations in which the added iron is rapidly scavenged from the

  4. Efficiency of small scale carbon mitigation by patch iron fertilization

    Directory of Open Access Journals (Sweden)

    J. L. Sarmiento

    2010-11-01

    Full Text Available While nutrient depletion scenarios have long shown that the high-latitude High Nutrient Low Chlorophyll (HNLC regions are the most effective for sequestering atmospheric carbon dioxide, recent simulations with prognostic biogeochemical models have suggested that only a fraction of the potential drawdown can be realized. We use a global ocean biogeochemical general circulation model developed at GFDL and Princeton to examine this and related issues. We fertilize two patches in the North and Equatorial Pacific, and two additional patches in the Southern Ocean HNLC region north of the biogeochemical divide and in the Ross Sea south of the biogeochemical divide. We evaluate the simulations using observations from both artificial and natural iron fertilization experiments at nearby locations. We obtain by far the greatest response to iron fertilization at the Ross Sea site, where sea ice prevents escape of sequestered CO2 during the wintertime, and the CO2 removed from the surface ocean by the biological pump is carried into the deep ocean by the circulation. As a consequence, CO2 remains sequestered on century time-scales and the efficiency of fertilization remains almost constant no matter how frequently iron is applied as long as it is confined to the growing season. The second most efficient site is in the Southern Ocean. The North Pacific site has lower initial nutrients and thus a lower efficiency. Fertilization of the Equatorial Pacific leads to an expansion of the suboxic zone and a striking increase in denitrification that causes a sharp reduction in overall surface biological export production and CO2 uptake. The impacts on the oxygen distribution and surface biological export are less prominent at other sites, but nevertheless still a source of concern. The century time scale retention of iron in this model greatly increases the long-term biological response to iron addition as compared with

  5. Iron fertilization enhanced net community production but not downward particle flux during the Southern Ocean iron fertilization experiment LOHAFEX

    Digital Repository Service at National Institute of Oceanography (India)

    Martin, P.; Loeff, M.M.R. van der.; Cassar, N.; Vandromme, P.; d'Ovidio, F.; Stemmann, L.; Rengarajan, R.; Soares, M.A.; Gonzalez, H.E.; Ebersbach, F.; Lampitt, R.S.; Sanders, R.; Barnett, B.A.; Smetacek, V.; Naqvi, S.W.A.

    A closed eddy core in the Subantarctic Atlantic Ocean was fertilized twice with two tons of iron (as FeSO4), and the 300 km2 fertilized patch was studied for 39 days to test whether fertilization enhances downward particle flux...

  6. Ocean fertilization with iron: effects on climate and air quality

    International Nuclear Information System (INIS)

    Liss, Peter; Chuck, Adele; Bakker, Dorothee; Turner, Suzanne

    2005-01-01

    It is well known that iron fertilization can increase primary production and hence CO 2 drawdown over a significant fraction of the oceans. What is less well established is the extent to which this leads to long-term sequestration of carbon to the deep oceans, and to feedbacks to the atmosphere arising from increased biological activity. In this note results for changes in trace gas concentrations during an iron addition experiment in the Southern Ocean are presented. They demonstrate that a complex situation exists; some gases (DMS, CH 3 I, CHBr 2 Cl) show increases in concentration following fertilization with iron while others show no change (CH 3 ONO 2 , CH 2 ClI) or even a decrease (CHBr 3 ). The concomitant effects on air/sea fluxes of these gases are potentially important for climate and atmospheric composition

  7. Efficiency of carbon removal per added iron in ocean iron fertilization

    NARCIS (Netherlands)

    de Baar, Hein J. W.; Gerringa, Loes J. A.; Laan, Patrick; Timmermans, Klaas R.

    2008-01-01

    The major response to ocean iron fertilization is by large diatoms, which at Fe-replete ambient seawater show an optimum C:Fe elemental ratio of similar to 23 000 and a higher ratio of similar to 160 000 or more under Fe-limited conditions. The efficiency of CO2 drawdown during the several weeks of

  8. Ocean iron fertilization in the context of the Kyoto protocol and the post-Kyoto process

    International Nuclear Information System (INIS)

    Bertram, Christine

    2010-01-01

    Ocean iron fertilization is currently discussed as a potential measure to mitigate climate change by enhancing oceanic CO 2 uptake. Its mitigation potential is not yet well explored, and carbon offsets generated through iron fertilization activities could currently not be traded on regulated carbon markets. Still, commercial interests in ocean iron fertilization already exist, which underlines the need to investigate a possible regulatory framework for it. To this end, I first discuss important basic aspects of ocean iron fertilization, namely its scientific background, quantitative potential, side effects, and costs. In a second step, I review regulatory aspects connected to ocean iron fertilization, like its legal status and open access issues. Moreover, I analyze how the regulations for afforestation and reforestation activities within the framework of the Kyoto Clean Development Mechanism (CDM) could be applied to ocean iron fertilization. Main findings are that the quantitative potential of ocean iron fertilization is limited, that costs are higher than initially hoped, and that potential adverse side effects are severe. Moreover, the legal status of ocean iron fertilization is currently not well defined, open access might cause inefficiencies, and the CDM regulations could not be easily applied to ocean iron fertilization.

  9. Regional contributions of ocean iron fertilization to atmospheric CO2 changes during the last glacial termination

    Science.gov (United States)

    Opazo, N. E.; Lambert, F.

    2017-12-01

    Mineral dust aerosols affect climate directly by changing the radiative balance of the Earth, and indirectly by acting as cloud condensation nuclei and by affecting biogeochemical cycles. The impact on marine biogeochemical cycles is primarily through the supply of micronutrients such as iron to nutrient-limited regions of the oceans. Iron fertilization of High Nutrient Low Chlorophyll (HNLC) regions of the oceans is thought to have significantly affected the carbon cycle on glacial-interglacial scales and contributed about one fourth of the 80-100 ppm lowering of glacial atmospheric CO2 concentrations.In this study, we quantify the effect of global dust fluxes on atmospheric CO2 using the cGENIE model, an Earth System Model of Intermediate Complexity with emphasis on the carbon cycle. Global Holocene and Last Glacial Maximum (LGM) dust flux fields were obtained from both dust model simulations and reconstructions based on observational data. The analysis was performed in two stages. In the first instance, we produced 8 global intermediate dust flux fields between Holocene and LGM and simulated the atmospheric CO2 drawdown due to these 10 dust levels. In the second stage, we only changed dust flux levels in specific HNLC regions to isolate the effect of these ocean basins. We thus quantify the contribution of the South Atlantic, the South Pacific, the North Pacific, and the Central Pacific HNLC regions to the total atmospheric CO2 difference due to iron fertilization of the Earth's oceans.

  10. The impact on atmospheric CO2 of iron fertilization induced changes in the ocean's biological pump

    Directory of Open Access Journals (Sweden)

    J. C. McWilliams

    2008-03-01

    Full Text Available Using numerical simulations, we quantify the impact of changes in the ocean's biological pump on the air-sea balance of CO2 by fertilizing a small surface patch in the high-nutrient, low-chlorophyll region of the eastern tropical Pacific with iron. Decade-long fertilization experiments are conducted in a basin-scale, eddy-permitting coupled physical/biogeochemical/ecological model. In contrast to previous studies, we find that most of the dissolved inorganic carbon (DIC removed from the euphotic zone by the enhanced biological export is replaced by uptake of CO2 from the atmosphere. Atmospheric uptake efficiencies, the ratio of the perturbation in air-sea CO2 flux to the perturbation in export flux across 100 m, integrated over 10 years, are 0.75 to 0.93 in our patch size-scale experiments. The atmospheric uptake efficiency is insensitive to the duration of the experiment. The primary factor controlling the atmospheric uptake efficiency is the vertical distribution of the enhanced biological production and export. Iron fertilization at the surface tends to induce production anomalies primarily near the surface, leading to high efficiencies. In contrast, mechanisms that induce deep production anomalies (e.g. altered light availability tend to have a low uptake efficiency, since most of the removed DIC is replaced by lateral and vertical transport and mixing. Despite high atmospheric uptake efficiencies, patch-scale iron fertilization of the ocean's biological pump tends to remove little CO2 from the atmosphere over the decadal timescale considered here.

  11. The impact on atmospheric CO2 of iron fertilization induced changes in the ocean's biological pump

    Science.gov (United States)

    Jin, X.; Gruber, N.; Frenzel, H.; Doney, S. C.; McWilliams, J. C.

    2008-03-01

    Using numerical simulations, we quantify the impact of changes in the ocean's biological pump on the air-sea balance of CO2 by fertilizing a small surface patch in the high-nutrient, low-chlorophyll region of the eastern tropical Pacific with iron. Decade-long fertilization experiments are conducted in a basin-scale, eddy-permitting coupled physical/biogeochemical/ecological model. In contrast to previous studies, we find that most of the dissolved inorganic carbon (DIC) removed from the euphotic zone by the enhanced biological export is replaced by uptake of CO2 from the atmosphere. Atmospheric uptake efficiencies, the ratio of the perturbation in air-sea CO2 flux to the perturbation in export flux across 100 m, integrated over 10 years, are 0.75 to 0.93 in our patch size-scale experiments. The atmospheric uptake efficiency is insensitive to the duration of the experiment. The primary factor controlling the atmospheric uptake efficiency is the vertical distribution of the enhanced biological production and export. Iron fertilization at the surface tends to induce production anomalies primarily near the surface, leading to high efficiencies. In contrast, mechanisms that induce deep production anomalies (e.g. altered light availability) tend to have a low uptake efficiency, since most of the removed DIC is replaced by lateral and vertical transport and mixing. Despite high atmospheric uptake efficiencies, patch-scale iron fertilization of the ocean's biological pump tends to remove little CO2 from the atmosphere over the decadal timescale considered here.

  12. The next generation of iron fertilization experiments in the southern Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Smetacek, V.; Naqvi, S.W.A.

    Of the various macro-engineering schemes proposed to mitigate global warming, ocean iron fertilization (OIF) is one that could be started at short notice on relevant scales. It is based on the reasoning that adding trace amounts of iron to iron...

  13. Deep carbon export from a Southern Ocean iron-fertilized diatom bloom

    Digital Repository Service at National Institute of Oceanography (India)

    Smetacek, V.; Klaas, C.; Strass, V.H.; Assmy, P.; Montresor, M.; Cisewski, B.; Savoye, N.; Webb, A.; d’Ovidio, F.; Arrieta, J.M.; Bathmann, U.; Bellerby, R.; Berg, G.M.; Croot, P.; Gonzalez, S.; Henjes, J.; Herndl, G.J.; Hoffmann, L.J.; Leach, H.; Losch, M.; Mills, M.M.; Neill, C.; Peeken, I.; Rottgers, R.; Sachs, O.; Sauter, E.; Schmidt, M.M.; Schwarz, J.; Terbruggen, A.; Wolf-Gladrow, D.

    Fertilization of the ocean by adding iron compounds has induced diatom-dominated phytoplankton blooms accompanied by considerable carbon dioxide drawdown in the ocean surface layer. However, because the fate of bloom biomass could not be adequately...

  14. Effect of sulfur and iron fertilizers on yield, yield components and ...

    African Journals Online (AJOL)

    Jane

    2011-06-13

    Jun 13, 2011 ... per plant. Interaction between water stress and combination of iron and sulfur fertilizers had significant .... Results of analysis of variance (ANOVA) of water stress (W), sulfur (B) and iron (C), and their interaction with gain yield, yield components and ... the soil structure and it increased the usefulness of other.

  15. The next generation of iron fertilization experiments in the Southern Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Smetacek, V.; Naqvi, S.W.A.

    of arguments pertaining to the fate of bloom biomass, the ratio of iron added to carbon sequestered and various side effects of fertilization, continue to cast doubt on its efficacy. The idea is also unpopular with the public because it is perceived as meddling...

  16. Stable Composition of the Nano- and Picoplankton Community during the Ocean Iron Fertilization Experiment LOHAFEX

    KAUST Repository

    Thiele, Stefan

    2014-11-17

    The iron fertilization experiment LOHAFEX was conducted in a cold-core eddy in the Southern Atlantic Ocean during austral summer. Within a few days after fertilization, a phytoplankton bloom developed dominated by nano- and picoplankton groups. Unlike previously reported for other iron fertilization experiments, a diatom bloom was prevented by iron and silicate co-limitation. We used 18S rRNA gene tag pyrosequencing to investigate the diversity of these morphologically similar cell types within the nano- and picoplankton and microscopically enumerated dominant clades after catalyzed reported deposition fluorescence in situ hybridization (CARD-FISH) with specific oligonucleotide probes. In addition to Phaeocystis, members of Syndiniales group II, clade 10–11, and the Micromonas clades ABC and E made up a major fraction of the tag sequences of the nano- and picoplankton community within the fertilized patch. However, the same clades were also dominant before the bloom and outside the fertilized patch. Furthermore, only little changes in diversity could be observed over the course of the experiment. These results were corroborated by CARD-FISH analysis which confirmed the presence of a stable nano- and picoplankton community dominated by Phaeocystis and Micromonas during the entire course of the experiment. Interestingly, although Syndiniales dominated the tag sequences, they could hardly be detected by CARD-FISH, possibly due to the intracellular parasitic life style of this clade. The remarkable stability of the nano- and picoplankton community points to a tight coupling of the different trophic levels within the microbial food web during LOHAFEX.

  17. Beta-Thalassemia Major and Female Fertility: The Role of Iron and Iron-Induced Oxidative Stress

    Science.gov (United States)

    Roussou, Paraskevi; Tsagarakis, Nikolaos J.; Diamanti-Kandarakis, Evanthia

    2013-01-01

    Endocrine complications due to haemosiderosis are present in a significant number of patients with beta-thalassemia major (BTM) worldwide and often become barriers in their desire for parenthood. Thus, although spontaneous fertility can occur, the majority of females with BTM is infertile due to hypogonadotropic hypogonadism (HH) and need assisted reproductive techniques. Infertility in these women seems to be attributed to iron deposition and iron-induced oxidative stress (OS) in various endocrine organs, such as hypothalamus, pituitary, and female reproductive system, but also through the iron effect on other organs, such as liver and pancreas, contributing to the impaired metabolism of hormones and serum antioxidants. Nevertheless, the gonadal function of these patients is usually intact and fertility is usually retrievable. Meanwhile, a significant prooxidants/antioxidants imbalance with subsequent increased (OS) exists in patients with BTM, which is mainly caused by tissue injury due to overproduction of free radicals by secondary iron overload, but also due to alteration in serum trace elements and antioxidant enzymes. Not only using the appropriate antioxidants, essential trace elements, and minerals, but also regulating the advanced glycation end products, could probably reduce the extent of oxidative damage and related complications and retrieve BTM women's infertility. PMID:24396593

  18. Iron fertilization of the Subantarctic Ocean during the last ice age

    Science.gov (United States)

    Martinez-Garcia, A.

    2015-12-01

    Dust has the potential to modify global climate by influencing the radiative balance of the atmosphere and by supplying iron and other essential limiting micronutrients to the ocean. The scarcity of iron limits marine productivity and carbon uptake in one-quarter of the world ocean where the concentration of major nutrients (phosphorus and nitrogen) is perennially high. The Southern Ocean is the region where variations in iron availability can have the largest effect on Earth's carbon cycle through its fertilizing effect on marine ecosystems. Paleoceanographic records from the Subantarctic Atlantic have revealed a remarkable correlation between phytoplankton productivity and aeolian iron flux during glacial periods supporting the iron fertilization hypothesis. In addition, a recent study has shown that peak glacial times and millennial cold events were nearly universally associated not only with increases in dust flux and export production, but also with an increase in nutrient consumption (the last indicated by higher foraminifera-bound δ15N) (Martinez-Garcia et al. 2014). This combination of changes is uniquely consistent with ice age iron fertilization of the Subantarctic Atlantic. The strengthening of the biological pump associated with the observed increase in Subantarctic nutrient consumption during the high-dust intervals of the last two ice ages can explain up to ~40 ppm of the CO2 decrease that characterizes the transitions from mid-climate states to full ice age conditions. However, the impact of iron fertilization in other sectors of the Southern Ocean characterized by lower ice age dust fluxes than the Atlantic remains unclear. A series of recently published records from the Subantarctic Pacific indicate that dust deposition and marine export production were three times higher during glacial periods than during interglacials (Lamy et al. 2014). Here we present new measurements of foraminifera-bound nitrogen isotopes in a sediment core located in the

  19. Carbonate counter pump stimulated by natural iron fertilization in the Polar Frontal Zone

    Science.gov (United States)

    Salter, Ian; Schiebel, Ralf; Ziveri, Patrizia; Movellan, Aurore; Lampitt, Richard; Wolff, George A.

    2014-12-01

    The production of organic carbon in the ocean's surface and its subsequent downward export transfers carbon dioxide to the deep ocean. This CO2 drawdown is countered by the biological precipitation of carbonate, followed by sinking of particulate inorganic carbon, which is a source of carbon dioxide to the surface ocean, and hence the atmosphere over 100-1,000 year timescales. The net transfer of CO2 to the deep ocean is therefore dependent on the relative amount of organic and inorganic carbon in sinking particles. In the Southern Ocean, iron fertilization has been shown to increase the export of organic carbon, but it is unclear to what degree this effect is compensated by the export of inorganic carbon. Here we assess the composition of sinking particles collected from sediment traps located in the Polar Frontal Zone of the Southern Ocean. We find that in high-nutrient, low-chlorophyll regions that are characterized by naturally high iron concentrations, fluxes of both organic and inorganic carbon are higher than in regions with no iron fertilization. However, the excess flux of inorganic carbon is greater than that of organic carbon. We estimate that the production and flux of carbonate in naturally iron-fertilized waters reduces the overall amount of CO2 transferred to the deep ocean by 6-32%, compared to 1-4% at the non-fertilized site. We suggest that an increased export of organic carbon, stimulated by iron availability in the glacial sub-Antarctic oceans, may have been accompanied by a strengthened carbonate counter pump.

  20. Optimizing nitrogen fertilizer use: Current approaches and simulation models

    International Nuclear Information System (INIS)

    Baethgen, W.E.

    2000-01-01

    Nitrogen (N) is the most common limiting nutrient in agricultural systems throughout the world. Crops need sufficient available N to achieve optimum yields and adequate grain-protein content. Consequently, sub-optimal rates of N fertilizers typically cause lower economical benefits for farmers. On the other hand, excessive N fertilizer use may result in environmental problems such as nitrate contamination of groundwater and emission of N 2 O and NO. In spite of the economical and environmental importance of good N fertilizer management, the development of optimum fertilizer recommendations is still a major challenge in most agricultural systems. This article reviews the approaches most commonly used for making N recommendations: expected yield level, soil testing and plant analysis (including quick tests). The paper introduces the application of simulation models that complement traditional approaches, and includes some examples of current applications in Africa and South America. (author)

  1. Multimicronutrient Slow-Release Fertilizer of Zinc, Iron, Manganese, and Copper

    Directory of Open Access Journals (Sweden)

    Siladitya Bandyopadhyay

    2014-01-01

    Full Text Available The process for the production of a slow-release micronutrient fertilizer is described. The compound contains zinc, iron, manganese, and copper as micronutrients and is produced by polymerizing a system containing phosphoric acid, zinc oxide, hematite, pyrolusite, copper sulfate, and magnesium oxide followed by neutralization of the polyphosphate chain with ammonium hydroxide. Changes in temperature, density, and viscosity of the reaction system during polymerization were studied. Reaction kinetics was studied at three different temperatures. Rate curves revealed a multistage process with essentially linear rates at each stage. Thus, each stage displayed zero order kinetics. The product was crystalline and revealed ordering of P-O-P chains. It had low solubility in water but high solubility in 0.33 M citric acid and 0.005 M DTPA. Three different field trials showed significant yield increments using the slow-release micronutrient fertilizer compared to the conventional micronutrients. Yield increments in rice were in the range of 10–55% over control (with no micronutrient and up to 17% over the conventional micronutrient fertilizers. There were significant increases in total uptake of zinc, iron, and manganese in the grain. Slow-release fertilizers also produced significant yield increases in potato as well as significant increase in vitamin C content of the tuber.

  2. Facile deferration of commercial fertilizers containing iron chelates for their NMR analysis.

    Science.gov (United States)

    Laghi, Luca; Alcañiz, Sara; Cerdán, Mar; Gomez-Gallego, Mar; Sierra, Miguel Angel; Placucci, Giuseppe; Cremonini, Mauro Andrea

    2009-06-24

    Ethylenediamine-N,N'-bis(o-hydroxyphenylacetic) acid (o,o-EDDHA) is widely used in commercial formulations as a Fe(3+) chelating agent to remedy iron shortage in calcareous and alkaline soils. Commercially available o,o-EDDHA-Fe(3+) formulations contain a mixture of EDDHA regioisomers (o,p-EDDHA and p,p-EDDHA), together with other, still uncharacterized, products. NMR spectroscopy can be applied to their study as long as iron is accurately removed prior to the observation. This paper shows that it is possible to obtain a deferrated solution of the organic ligands present in commercial fertilizers containing the EDDHA-Fe(3+) chelate by treating the chelate with ferrocyanide, thus forming Prussian Blue that can be easily removed by centrifugation. This iron removal process does not cause significant losses of the o,o-EDDHA ligand or its minor structural isomers.

  3. NMR analysis of the iron ligand ethylenediaminedi(o-hydroxyphenyl)acetic acid (EDDHA) employed in fertilizers.

    Science.gov (United States)

    Cremonini, M A; Alvarez-Fernández, A; Lucena, J J; Rombolà, A; Marangoni, B; Placucci, G

    2001-08-01

    The exceptional efficiency of the iron chelate of ethylenediaminedi(o-hydroxyphenyl)acetic acid (o,o-EDDHA) in correcting iron chlorosis in plants and the medical applications of various metallic chelates of this compound have long been recognized. As commercial preparations of o,o-EDDHA usually contain impurities, a method for their detection is proposed. By using one- and two-dimensional nuclear magnetic resonance two impurities were identified. The structure of one of these compounds was assigned to an isomer of EDDHA containing at least one p-hydroxyphenyl moiety. The structure of the other impurity was tentatively assigned to a byproduct of the EDDHA synthesis: 2,6-di[CH(COOH)NHCH(2)CH(2)NHCH(COOH)Ar]phenol (Ar = hydroxyphenyl). Both compounds were also detected in the EDDHA extracted from a commercial iron fertilizer.

  4. Iron fertilization with FeEDDHA : the fate and effectiveness of FeEDDHA chelates in soil-plant systems

    OpenAIRE

    Schenkeveld, W.D.C.

    2010-01-01

    Iron deficiency chlorosis is a nutritional disorder in plants which reduces crop yields both quantitatively and qualitatively, and causes large economic losses. It occurs world-wide, predominantly in plants grown on calcareous soils, as a result of a limited bioavailability of iron related to the poor solubility of iron at high soil-pH (7.5-8.5). Iron fertilizers based on FeEDDHA (iron ethylene diamine-N,N'-bis(hydroxy phenyl acetic acid)) chelates are among the most efficient in preventing a...

  5. Synthesis of iron fertilization experiments : From the iron age in the age of enlightenment

    NARCIS (Netherlands)

    de Baar, HJW; Boyd, PW; Coale, KH; Landry, MR; Tsuda, A; Assmy, P; Bakker, DCE; Bozec, Y; Barber, RT; Brzezinski, MA; Buesseler, KO; Boye, M; Croot, PL; Gervais, F; Gorbunov, MY; Harrison, PJ; Hiscock, WT; Laan, P; Lancelot, C; Law, CS; Levasseur, M; Marchetti, A; Millero, FJ; Nishioka, J; Nojiri, Y; van Oijen, T; Riebesell, U; Rijkenberg, MJA; Saito, H; Takeda, S; Timmermans, KR; Veldhuis, MJW; Waite, AM

    2005-01-01

    [1] Comparison of eight iron experiments shows that maximum Chl a, the maximum DIC removal, and the overall DIC/ Fe efficiency all scale inversely with depth of the wind mixed layer (WML) defining the light environment. Moreover, lateral patch dilution, sea surface irradiance, temperature, and

  6. Retrospective satellite ocean color analysis of purposeful and natural ocean iron fertilization

    Science.gov (United States)

    Westberry, Toby K.; Behrenfeld, Michael J.; Milligan, Allen J.; Doney, Scott C.

    2013-03-01

    Significant effort has been invested in understanding the role of iron in marine ecosystems over the past few decades. What began as shipboard amendment experiments quickly grew into a succession of in situ, mesoscale ocean iron fertilization (OIF) experiments carried out in all three high nutrient low chlorophyll (HNLC) regions of the world ocean. Dedicated process studies have also looked at regions of the ocean that are seasonally exposed to iron-replete conditions as natural OIF experiments. However, one problem common to many OIF experiments is determination of biological response beyond the duration of the experiment (typicallyfloristic shifts in the phytoplankton community. Further, a consistent pattern of decreased satellite fluorescence efficiency (FLH:Chl or ϕf) following OIF is observed that is in agreement with current understanding of phytoplankton physiological responses to relief from iron stress. The current study extends our ability to retrieve phytoplankton physiology from space-based sensors, strengthens the link between satellite fluorescence and iron availability, and shows that satellite ocean color analyses provide a unique tool for monitoring OIF experiments.

  7. No iron fertilization in the equatorial Pacific Ocean during the last ice age.

    Science.gov (United States)

    Costa, K M; McManus, J F; Anderson, R F; Ren, H; Sigman, D M; Winckler, G; Fleisher, M Q; Marcantonio, F; Ravelo, A C

    2016-01-28

    The equatorial Pacific Ocean is one of the major high-nutrient, low-chlorophyll regions in the global ocean. In such regions, the consumption of the available macro-nutrients such as nitrate and phosphate is thought to be limited in part by the low abundance of the critical micro-nutrient iron. Greater atmospheric dust deposition could have fertilized the equatorial Pacific with iron during the last ice age--the Last Glacial Period (LGP)--but the effect of increased ice-age dust fluxes on primary productivity in the equatorial Pacific remains uncertain. Here we present meridional transects of dust (derived from the (232)Th proxy), phytoplankton productivity (using opal, (231)Pa/(230)Th and excess Ba), and the degree of nitrate consumption (using foraminifera-bound δ(15)N) from six cores in the central equatorial Pacific for the Holocene (0-10,000 years ago) and the LGP (17,000-27,000 years ago). We find that, although dust deposition in the central equatorial Pacific was two to three times greater in the LGP than in the Holocene, productivity was the same or lower, and the degree of nitrate consumption was the same. These biogeochemical findings suggest that the relatively greater ice-age dust fluxes were not large enough to provide substantial iron fertilization to the central equatorial Pacific. This may have been because the absolute rate of dust deposition in the LGP (although greater than the Holocene rate) was very low. The lower productivity coupled with unchanged nitrate consumption suggests that the subsurface major nutrient concentrations were lower in the central equatorial Pacific during the LGP. As these nutrients are today dominantly sourced from the Subantarctic Zone of the Southern Ocean, we propose that the central equatorial Pacific data are consistent with more nutrient consumption in the Subantarctic Zone, possibly owing to iron fertilization as a result of higher absolute dust fluxes in this region. Thus, ice-age iron fertilization in the

  8. Simulating Precambrian banded iron formation diagenesis

    DEFF Research Database (Denmark)

    Posth, Nicole R.; K??hler, Inga; D. Swanner, Elizabeth

    2013-01-01

    Post-depositional diagenetic alteration makes the accurate interpretation of key precipitation processes in ancient sediments, such as Precambrian banded iron formations (BIFs), difficult. While microorganisms are proposed as key contributors to BIF deposition, the diagenetic transformation...

  9. Simulation of a Sponge Iron Production Process

    Directory of Open Access Journals (Sweden)

    Tor Onshus

    1983-07-01

    Full Text Available A model for reduction of FeO with hydrogen in a countercurrent moving bed reactor is summarized. This model is a special case of a mor ecomplete model which also includes reduction of the higher oxides, hematite and magnetite, with a mixture of reducing gases, thus describing the production of direct-reduced iron from iron ores. Equations governing the heat and mass transfer between the gas and solid phase are not given here, but play an important role in the dynamic bahviour of the model.

  10. Iron fertilization and the structure of planktonic communities in high nutrient regions of the Southern Ocean

    Science.gov (United States)

    Quéguiner, Bernard

    2013-06-01

    In this review article, plankton community structure observations are analyzed both for artificial iron fertilization experiments and also for experiments dedicated to the study of naturally iron-fertilized systems in the Atlantic, Indian and Pacific sectors of the Southern Ocean in the POOZ (Permanently Open Ocean Zone) and the PFZ (Polar Frontal Zone). Observations made in natural systems are combined with those from artificially perturbed systems, in order to evaluate the seasonal evolution of pelagic communities, taking into account controlling factors related to the life cycles and the ecophysiology of dominant organisms. The analysis considers several types of planktonic communities, including both autotrophs and heterotrophs. These communities are spatially segregated owing to different life strategies. A conceptual general scheme is proposed to account for these observations and their variability, regardless of experiment type. Diatoms can be separated into 2 groups: Group 1 has slightly silicified fast growing cells that are homogeneously distributed in the surface mixed layer, and Group 2 has strongly silicified slowly growing cells within discrete layers. During the growth season, Group 1 diatoms show a typical seasonal succession of dominant species, within time windows of development that are conditioned by physical factors (light and temperature) as well as endogenous specific rhythms (internal clock), and biomass accumulation is controlled by the availability of nutrients. Group 1 diatoms are not directly grazed by mesozooplankton which is fed by protozooplankton, linking the microbial food web to higher trophic levels. Instead, successive dominant species of Group 1 are degraded via bacterial activity at the end of their growth season. Organic detritus fragments feed protozooplankton and mesozooplankton. The effective silicon pump leads to the progressive disappearance of silicic acid in surface waters. In contrast, Group 2 is resistant to grazing

  11. Iron phosphate glass containing simulated fast reactor waste: Characterization and comparison with pristine iron phosphate glass

    International Nuclear Information System (INIS)

    Joseph, Kitheri; Asuvathraman, R.; Venkata Krishnan, R.; Ravindran, T.R.; Govindaraj, R.; Govindan Kutty, K.V.; Vasudeva Rao, P.R.

    2014-01-01

    Detailed characterization was carried out on an iron phosphate glass waste form containing 20 wt.% of a simulated nuclear waste. High temperature viscosity measurement was carried out by the rotating spindle method. The Fe 3+ /Fe ratio and structure of this waste loaded iron phosphate glass was investigated using Mössbauer and Raman spectroscopy respectively. Specific heat measurement was carried out in the temperature range of 300–700 K using differential scanning calorimeter. Isoconversional kinetic analysis was employed to understand the crystallization behavior of the waste loaded iron phosphate glass. The glass forming ability and glass stability of the waste loaded glass were also evaluated. All the measured properties of the waste loaded glass were compared with the characteristics of pristine iron phosphate glass

  12. Using Perls Staining to Trace the Iron Uptake Pathway in Leaves of a Prunus Rootstock Treated with Iron Foliar Fertilizers.

    Science.gov (United States)

    Rios, Juan J; Carrasco-Gil, Sandra; Abadía, Anunciación; Abadía, Javier

    2016-01-01

    The aim of this study was to trace the Fe uptake pathway in leaves of Prunus rootstock (GF 677; Prunus dulcis × Prunus persica) plants treated with foliar Fe compounds using the Perls blue method, which detects labile Fe pools. Young expanded leaves of Fe-deficient plants grown in nutrient solution were treated with Fe-compounds using a brush. Iron compounds used were the ferrous salt FeSO4, the ferric salts Fe2(SO4)3 and FeCl3, and the chelate Fe(III)-EDTA, all of them at concentrations of 9 mM Fe. Leaf Fe concentration increases were measured at 30, 60, 90 min, and 24 h, and 70 μm-thick leaf transversal sections were obtained with a vibrating microtome and stained with Perls blue. In vitro results show that the Perls blue method is a good tool to trace the Fe uptake pathway in leaves when using Fe salts, but is not sensitive enough when using synthetic Fe(III)-chelates such as Fe(III)-EDTA and Fe(III)-IDHA. Foliar Fe fertilization increased leaf Fe concentrations with all Fe compounds used, with inorganic Fe salts causing larger leaf Fe concentration increases than Fe(III)-EDTA. Results show that Perls blue stain appeared within 30 min in the stomatal areas, indicating that Fe applied as inorganic salts was taken up rapidly via stomata. In the case of using FeSO4 a progression of the stain was seen with time toward vascular areas in the leaf blade and the central vein, whereas in the case of Fe(III) salts the stain mainly remained in the stomatal areas. Perls stain was never observed in the mesophyll areas, possibly due to the low concentration of labile Fe pools.

  13. Effect of phosphate fertilization on the bioavailability of iron in calcareous soils

    Science.gov (United States)

    Sánchez-Rodríguez, A. R.; del Campillo, M. C.; Barrón, V.; Torrent, J.

    2012-04-01

    Iron (Fe) chlorosis is the most important nutritional problem in sensitive plant species cultivated in calcareous soils, its main symptoms being interveinal yellowing in the younger leaves due to lack of chlorophyll and reduced growth. Fe chlorosis has been related to the content of poorly crystalline Fe oxides in soil. The effect of other nutrients, especially phosphorus (P), is, however, a matter of debate. In this work we examined whether fertilization with P alters the availability of Fe to sensitive plants growing in two different Fe chlorosis-inducing calcareous soils. Phosphate at rates of 0 (control), 25, 50, 100 and 200 mg P kg-1 soil was applied to pots where six-months-old olive trees cv. Arbequina were grown. The experiment lasted three years and took place in a shaded house. Chlorophyll concentration in the young leaves was estimated with the SPAD value (using a Minolta apparatus) three-four times per year. Furthermore, shoot length, dry weight of annual pruning and mineral element concentration were measured at the end of each year. In one of the soils, SPAD and leaf Fe concentration decreased with increasing P dose. However in the other soil, SPAD was not correlated with the rate of applied P. In both soils, potassium and zinc concentrations in plants fertilized with P were lower than those in the control plants. This work was funded by the Spanish Ministry of Science and Innovation, Projects: AGL 2005-06691-C02-01 and AGL 2008-05053-C02-02, and the European Regional Development Funds. ARSR acknowledges the finnancial support from the Spanish Ministry of Education as a fellow of the program "Training of University Teachers" (Formación del Profesorado Universitario, AP2008-04716)

  14. Dust fluxes and iron fertilization in Holocene and Last Glacial Maximum climates

    Science.gov (United States)

    Lambert, Fabrice; Tagliabue, Alessandro; Shaffer, Gary; Lamy, Frank; Winckler, Gisela; Farias, Laura; Gallardo, Laura; De Pol-Holz, Ricardo

    2015-07-01

    Mineral dust aerosols play a major role in present and past climates. To date, we rely on climate models for estimates of dust fluxes to calculate the impact of airborne micronutrients on biogeochemical cycles. Here we provide a new global dust flux data set for Holocene and Last Glacial Maximum (LGM) conditions based on observational data. A comparison with dust flux simulations highlights regional differences between observations and models. By forcing a biogeochemical model with our new data set and using this model's results to guide a millennial-scale Earth System Model simulation, we calculate the impact of enhanced glacial oceanic iron deposition on the LGM-Holocene carbon cycle. On centennial timescales, the higher LGM dust deposition results in a weak reduction of pump. This is followed by a further ~10 ppm reduction over millennial timescales due to greater carbon burial and carbonate compensation.

  15. Regulation of Ocean Iron Fertilization (OIF): a Model for Balancing Research, Environmental and Policy Concerns

    Science.gov (United States)

    Leinen, M.; Lamotte, R.

    2008-12-01

    The potential of enhancing carbon sequestration by the biosphere for climate mitigation often raises questions of offsetting effects. These questions become more important as the scale of the enhancement increases. Ocean iron fertilization is accompanied by additional questions related to use of the ocean commons. The London Convention (LC) and London Protocol (LP), international treaties adopted in 1972 and 1996 respectively, were designed to prevent use of the ocean for disposal of toxic, harmful and radioactive pollutants. Recently the LC/LP has been called upon to decide whether climate mitigation activities, such as subseafloor injection of CO2 and OIF, are legal under the framework and, if so, how they should be regulated. The broad consultation with the science community by the LC/LP in developing their perspective, and the involvement of the NGO community in these deliberations, provides a model for the process that the international policy community can use to develop science-based regulatory guidelines for carbon mitigation projects involving the commons. And the substance of that emerging regulatory framework -- built on a national-level permitting process informed by internationally agreed guidelines and standards -- may also serve as a model for the oversight of other emerging technologies that take place in the global commons.

  16. Molecular dynamics simulation of displacement cascades in iron-alpha

    International Nuclear Information System (INIS)

    Vascon, R.

    1997-01-01

    Radiation damage by neutrons or ions in bcc iron has been investigated by molecular dynamics simulations using an embedded atom type many-body potential (EAM). Displacement cascades with energies of 1 to 30 keV were generated in the microcanonical system where the number of atoms (up to 1.5 million) is chosen high enough to compensate the fact that the dissipation of energy is not taken into account in our model. The defect number at the end of cascade lifetime was found to be 60 percent of the NRT standard value. This tendency is in good agreement with experimental data. However, compared with other simulations in iron, we found significant differences in the defect production and distribution. The comparison with results obtained form simulations of cascades in other metals, leads on the one hand to a higher value of the defect number in bcc iron than in fcc metals like copper or nickel, and on the other hand to a ratio, between the number of replacements and the number of defects, lower in iron ( 100). We observed the transient melting of the core of the cascade during simulations. We showed that a higher value of the initial iron crystal temperature, as the mass difference between the components of an artificial binary alloy Fe-X(X=Al,Sb,Au,U) both produce a 'cascade effect': a decrease of the number of defects and an increase of the number of replacements. We also showed up the quasi-channeling of some atoms in high energy cascades. They are at the origin of sub-cascades formation; as a result they induce an opposite effect to the 'cascade effect'. (author)

  17. Finite element simulation of ironing process under warm conditions

    Directory of Open Access Journals (Sweden)

    Swadesh Kumar Singh

    2014-01-01

    Full Text Available Metal forming is one of the most important steps in manufacturing of a large variety of products. Ironing in deep drawing is done by adjusting the clearance between the punch and the die and allow the material flow over the punch. In the present investigation effect of extent of ironing behavior on the characteristics of the product like thickness distribution with respect to temperature was studied. With the help of finite element simulation using explicit finite element code LS-DYNA the stress in the drawn cup were predicted in the drawn cup. To increase the accuracy in the simulation process, numbers of integration points were increased in the thickness direction and it was found that there is very close prediction of finite element results to that of experimental ones.

  18. Stable Composition of the Nano- and Picoplankton Community during the Ocean Iron Fertilization Experiment LOHAFEX

    KAUST Repository

    Thiele, Stefan; Wolf, Christian; Schulz, Isabelle Katharina; Assmy, Philipp; Metfies, Katja; Fuchs, Bernhard M.

    2014-01-01

    , clade 10–11, and the Micromonas clades ABC and E made up a major fraction of the tag sequences of the nano- and picoplankton community within the fertilized patch. However, the same clades were also dominant before the bloom and outside the fertilized

  19. The regulatory role of endogenous iron on greenhouse gas emissions under intensive nitrogen fertilization in subtropical soils of China.

    Science.gov (United States)

    Han, Jiangpei; Shi, Liangsheng; Wang, Yakun; Chen, Zhuowei; Wu, Laosheng

    2018-05-01

    Anaerobic batch experiments were conducted to study the regulatory role of endogenous iron in greenhouse gas emissions under intensive nitrogen fertilization in subtropical soils of China. Fe 2+ , Fe 3+ , and NO 3 - -N dynamics and N 2 O, CH 4 , and CO 2 emissions, as well as the relationships between N fertilizer, endogenous iron, and greenhouse gas emissions were investigated. The emissions of N 2 O increased to different extents from all the test soils by N1 (260 mg N kg -1 ) application compared with N0. After 24 days of anaerobic incubation, the cumulative emissions of N 2 O from red soils in De'an (DR) were significantly higher than that from paddy soils in De'an (DP) and Qujialing (QP) under N1. However, N application enhanced CH 4 and CO 2 emissions from the red soils slightly but inhibited the emissions from paddy soils. The maximal CH 4 and CO 2 emission fluxes occurred in DP soil without N input. Pearson's correlation analysis showed that there were significant correlations (P greenhouse gas emissions mainly through the involvement in denitrification. The proportion of the electrons donated by Fe 2+ used for N 2 O production in denitrification in DP soil was approximately 37.53%. Moreover, positive correlations between Fe 2+ and CH 4 , CO 2 were found in both DR and QP soils, suggesting that endogenous iron might regulate the anaerobic decomposition of organic carbon to CH 4 and CO 2 in the two soils. Soil pH was also an important factor controlling greenhouse gas emissions by affecting endogenous iron availability and C and N transformation processes.

  20. Links between Iron Fertilization and Biological Pump Efficiency in the Bering Sea Over the Last 3.5 Myrs

    Science.gov (United States)

    Bartoli, G. L.; Studer, A. S.; Martinez Garcia, A.; Haug, G. H.

    2011-12-01

    The Bering Sea is one of the major sink of atmospheric CO2 today, due to the efficiency of its biological pump, despite a limitation by iron. Here we present records of iron fertilization by aeolian dust deposition (n-alkane concentration) and phytoplankton nutrient consumption (diatom-bound δ15N record) over the last 3.5 Myrs in the southwestern Bering Sea at Site U1341 drilled during IODP Expedition 323. During the Pliocene Epoch, when sea surface temperatures were 3-4°C warmer than today and sea-ice cover was reduced, the biological pump efficiency during glacial and interglacial stages was minimal, similar to Quaternary interglacials. Low iron deposition and weaker surface water stratification resulting in higher nutrient inputs contributed to reduce the biological pump efficiency until 1.5 Ma. After the intensification of glacial conditions in the Bering Sea and the increase in sea-ice cover and iron inputs, the biological pump efficiency progressively increased, reaching values similar to Quaternary glacials after the mid-Pleistocene transition.

  1. Magnetic transmission gear finite element simulation with iron pole hysteresis

    Science.gov (United States)

    Filippini, Mattia; Alotto, Piergiorgio; Glehn, Gregor; Hameyer, Kay

    2018-04-01

    Ferromagnetic poles in a magnetic transmission gear require particular attention during their design process. Usually, during the numerical simulation of these devices the effects of hysteresis for loss estimation are neglected and considered only during post-processing calculations. Since the literature lacks hysteresis models, this paper adopts a homogenized hysteretic model able to include eddy current and hysteresis losses in 2D laminated materials for iron poles. In this article the results related to the hysteresis in a magnetic gear are presented and compared to the non-hysteretic approach.

  2. Determine the Optimal Levels of Bio-fertilizers and Foliar Application of Iron on Yield and Quality Indices of Roselle (Hibiscus sabdariffa L.

    Directory of Open Access Journals (Sweden)

    zahra mir

    2018-02-01

    Full Text Available Introduction In conventional agricultural systems to obtain the highest performance continuous use of chemical fertilizers is inevitable. The health of the plant, soil and living matter depends on the rotation of food elements in the ecosystem. This cycle is disrupted as a result of the loss of soil fertility, its food imbalance and inappropriate cultivation practices. Bio-fertilizers are composed of beneficial microorganisms, each for a specific purpose, such as nitrogen fixation, release of phosphate ions, potassium, iron. It should be noted that most studies in the field for sour Roselle (Hibiscus sabdariffa are based on the use of various chemical fertilizers, but the reaction of this plant to bio-fertilizers and iron solubilization has not been considered. Therefore, this study aimed to investigate the effect of bio fertilizers and iron on yield and quality traits of Roselle in hot and dry weather conditions. Materials and Methods In order to investigate the effects of bio-fertilizers and foliar application iron on yield and quality indicators Roselle (Hibiscus sabdariffa experiment in Research field of Zabol University Agriculture Institute in 2015-2016 years was performed with split-plot based on completely randomized design and three replications. Treatments consisted of four levels of bio-fertilizers: control (without fertilizer, vermicompost, cow manure, seaweed and iron foliar applications include: lack of iron, foliar application at a rate of 3cc per thousand, 6cc per thousand was considered. As a source of bio-fertilizer treatments and foliar application iron levels were considered as sub plots. Before sowing Roselle seeds, vermicompost and manure were added to the soil and inoculation operation . Measurements were: economic yield, biological yield, harvest index, chlorophyll a, b and carotenoids, anthocyanins, carbohydrates and protein. Statistical analysis of data was done with SAS software version 9.1 and mean comparison with

  3. Computer simulation of cascade damage in iron: PKA mass effects

    International Nuclear Information System (INIS)

    Calder, A.; Bacon, D.J.; Barashev, A.; Osetsky, Y.

    2007-01-01

    Full text of publication follows: Results are presented from an extensive series of computer simulations of the damage created by displacement cascades in alpha-iron. The objective has been to determine for the first time the effect of the mass of the primary knock-on atom (PKA) on defect number, defect clustering and cluster morphology. Cascades with PKA energy in the range 5 to 20 keV have been simulated by molecular dynamics for temperature up to 600 K using an interatomic potential for iron for which the energy difference between the dumbbell interstitial and the crowdion is close to the value from ab initio calculation (Ackland et al., J. Phys.: Condens. Matter 2004). At least 30 cascades have been simulated for each condition in order to generate reasonable statistics. The influence of PKA species on damage has been investigated in two ways. In one, the PKA atom was treated as an Fe atom as far as its interaction with other atoms was concerned, but its atomic weight (in amu) was either 12 (C), 56 (Fe) or 209 (Bi). Pairs of Bi PKAs have also been used to mimic heavy molecular ion irradiation. In the other approach, the short-range pair part of the interatomic potential was changed from Fe-Fe to that for Bi-Fe, either with or without a change of PKA mass, in order to study the influence of high-energy collisions on the cascade outcome. It is found that PKA mass is more influential than the interatomic potential between the PKA and Fe atoms. At low cascade energy (5-10 keV), increasing PKA mass leads to a decrease in number of interstitials and vacancies. At high energy (20 keV), the main effect of increasing mass is to increase the probability of creation of interstitial and vacancy clusters in the form of 1/2 and dislocation loops. The simulation results are consistent with experimental TEM observations of damage in irradiated iron. (authors)

  4. The Effect of Iron Fertilization on Nodulation, Yield and Yield Traits ...

    African Journals Online (AJOL)

    1984). Fe deficiency also primarily affects the structure and functioning of the .... polyethylene bags containing 200 g of soybean seeds. ... seed coat. ..... iron application could also be related to genetic make-up of the host, which regulates the.

  5. The analysis on of the effect of urea, iron sulfate and vermicompost fertilizers on the growth characteristics and yield of sunflower (Helianthus annuus L. The city Darreh Gaz

    Directory of Open Access Journals (Sweden)

    mahdiyeh zomorrodi

    2015-12-01

    Full Text Available To study the effect of vermicompost and urea and iron sulfate fertilizers on the growth characteristics and yield of sunflower seed (Helianthus annuus L. an pediment was conducted in Darreh Gaz located in Khorasan Razavi province in 2012. Factorial experiment in a randomized complete block design with three factors and three repetition. In this experiment three levels of urea (50; 150 and 250 kg per hectare as the first factor and two level of vermicompost (7 tons per hectare consumption and non-consumption as the second factor and two iron sulfate (80 kilogram per hectare consumption and non- consumption were considered as the third factor. The results showed that the effect of urea × vermicompost treatment combination on stem height, head diameter, stem dry weight and yield was significantly at one percent probability level. The treatment combination of 250 kg. ha-1 × iron sulfate× vermicompost increased plant height, head diameter, petiole dry weight. Vermicompost × iron sulfate treatment combination on the dry weight’s leaf, petiole, stem and head were the highest significant (p≤0.01. The application of vermicompost × iron sulfate treatment combination resulted in the highest rate of stem diameter, leaf dry weight and stem the highest yield belonged to 250 kg.ha-1 × vermicompost. Iron sulfate use different amounts of urea fertilizer redact yield. The lowest yield of 250 kg.ha-1× iron sulfate was related to treatment combination. So it seems that the combined application of organic vermicompost fertilizer and urea and iron sulfate fertilizers on the growth and yield of sunflower Darreh Gaz can be effective in improving properties.

  6. Iron

    Science.gov (United States)

    Iron is a mineral that our bodies need for many functions. For example, iron is part of hemoglobin, a protein which carries ... It helps our muscles store and use oxygen. Iron is also part of many other proteins and ...

  7. Formation of iron nanoparticles and increase in iron reactivity in mineral dust during simulated cloud processing.

    Science.gov (United States)

    Shi, Zongbo; Krom, Michael D; Bonneville, Steeve; Baker, Alex R; Jickells, Timothy D; Benning, Liane G

    2009-09-01

    The formation of iron (Fe) nanoperticles and increase in Fe reactivity in mineral dust during simulated cloud processing was investigated using high-resolution microscopy and chemical extraction methods. Cloud processing of dust was experimentally simulated via an alternation of acidic (pH 2) and circumneutral conditions (pH 5-6) over periods of 24 h each on presieved (formation of Fe-rich nanoparticle aggregates, which were not found initially. Similar Fe-rich nanoparticles were also observed in wet-deposited Saharen dusts from the western Mediterranean but not in dry-deposited dust from the eastern Mediterranean. Sequential Fe extraction of the soil samples indicated an increase in the proportion of chemically reactive Fe extractable by an ascorbate solution after simulated cloud processing. In addition, the sequential extractions on the Mediterranean dust samples revealed a higher content of reactive Fe in the wet-deposited dust compared to that of the dry-deposited dust These results suggestthat large variations of pH commonly reported in aerosol and cloud waters can trigger neo-formation of nanosize Fe particles and an increase in Fe reactivity in the dust

  8. A review of mathematical modeling and simulation of controlled-release fertilizers.

    Science.gov (United States)

    Irfan, Sayed Ameenuddin; Razali, Radzuan; KuShaari, KuZilati; Mansor, Nurlidia; Azeem, Babar; Ford Versypt, Ashlee N

    2018-02-10

    Nutrients released into soils from uncoated fertilizer granules are lost continuously due to volatilization, leaching, denitrification, and surface run-off. These issues have caused economic loss due to low nutrient absorption efficiency and environmental pollution due to hazardous emissions and water eutrophication. Controlled-release fertilizers (CRFs) can change the release kinetics of the fertilizer nutrients through an abatement strategy to offset these issues by providing the fertilizer content in synchrony with the metabolic needs of the plants. Parametric analysis of release characteristics of CRFs is of paramount importance for the design and development of new CRFs. However, the experimental approaches are not only time consuming, but they are also cumbersome and expensive. Scientists have introduced mathematical modeling techniques to predict the release of nutrients from the CRFs to elucidate fundamental understanding of the dynamics of the release processes and to design new CRFs in a shorter time and with relatively lower cost. This paper reviews and critically analyzes the latest developments in the mathematical modeling and simulation techniques that have been reported for the characteristics and mechanisms of nutrient release from CRFs. The scope of this review includes the modeling and simulations techniques used for coated, controlled-release fertilizers. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Origin and fate of particulate and dissolved organic matter in a naturally iron-fertilized region of the Southern Ocean

    Science.gov (United States)

    Tremblay, L.; Caparros, J.; Leblanc, K.; Obernosterer, I.

    2015-01-01

    Natural iron fertilization of high-nutrient low-chlorophyll (HNLC) waters induces annually occurring spring phytoplankton blooms off the Kerguelen Islands (Southern Ocean). To examine the origin and fate of particulate and dissolved organic matter (POM and DOM), D- and L-amino acids (AA) were quantified at bloom and HNLC stations. Total hydrolyzable AA accounted for 21-25% of surface particulate organic carbon (%POCAA) at the bloom sites, but for 10% at the HNLC site. A marked decrease in %POCAA with depth was observed at the most productive stations leading to values between 3 and 5% below 300 m depth. AA contributed to only 0.9-4.4% of dissolved organic carbon (%DOCAA) at all stations. The only consistent vertical trend was observed at the most productive station (A3-2) where %DOCAA decreased from ~ 2% in the surface waters to 0.9% near 300 m. These AA yields revealed that POM and DOM were more rapidly altered or mineralized at the bloom sites compared to the HNLC site. Alteration state was also assessed by trends in C / N ratio, %D-AA and degradation index. Different molecular markers indicated that POM mostly originated from diatoms and bacteria. The estimated average proportion of POM from intact phytoplankton cells in surface waters was 45% at the bloom station A3-2, but 14% at the HNLC site. Estimates based on D-AA yields indicated that ~ 15% of POM and ~ 30% of DOM was of bacterial origin (cells and cell fragments) at all stations. Surprisingly, the DOM in HNLC waters appeared less altered than the DOM from the bloom, had slightly higher dissolved AA concentrations, and showed no sign of alteration within the water column. Unfavorable conditions for bacterial degradation in HNLC regions can explain these findings. In contrast, large inputs of labile organic molecules and iron likely stimulate the degradation of organic matter (priming effect) and the production of more recalcitrant DOM (microbial carbon pump) during iron-fertilized blooms.

  10. Quantitative Mechanistic Description of Natural Radionuclide and Iron Sorption on phosphate Fertilizer Materials

    International Nuclear Information System (INIS)

    Kamel, N.H.M.

    2008-01-01

    The mean activity values of the radionuclide 226 Ra, 238 U and 232 Th decay series, and the radioactive isotopes of 40 K in Bq/kg dry weight of the phosphate ore (Pho-ore), single super phosphate granules, (SSP-G), single super phosphate powder (SSP-P), triple super phosphate (TSP), and phosphogypsum (CaSO 4 ) samples were determined. CaSO 4 sample was found to contain, 300 Bq/kg of radioactive 238 U which is less than the values found in other studied phosphate samples. CaSO 4 sample was found to contain the highest amount of 226 Ra concentration value of 850 Bq/kg. Phosphate fertilizer components are acidic character, therefore, the solid surfaces will in general acquire a surface electric charge when contact with polar solvent such as water. The net electric charge obtained through uptake or release of potential determining ions (e.g, H + or OH - ). Thus the solid surfaces tend to adsorb and/or release of different ions to maintain neutral. The aim of this study is to determine the electric charge and the surface electric potential at the phosphate fertilizer materials

  11. Comparing the performance of 11 crop simulation models in predicting yield response to nitrogen fertilization

    OpenAIRE

    Salo , Tapio J.; Palosuo , Taru; Kersebaum , Kurt Christian; Nendel , Claas; Angulo , Carlos; Ewert , Frank; Bindi , Marco; Calanca , Pierluigi; Klein , Tommy; Moriondo , Marco; Ferrise , Roberto; Olesen , Jørgen Eivind; Patil , Rasmi H.; Ruget , Francoise; Takac , Jozef

    2016-01-01

    Eleven widely used crop simulation models (APSIM, CERES, CROPSYST, COUP, DAISY, EPIC, FASSET, HERMES, MONICA, STICS and WOFOST) were tested using spring barley (Hordeum vulgare L.) data set under varying nitrogen (N) fertilizer rates from three experimental years in the boreal climate of Jokioinen, Finland. This is the largest standardized crop model inter-comparison under different levels of N supply to date. The models were calibrated using data from 2002 and 2008, of which 2008 included si...

  12. Present and Past Impact of Glacially Sourced Dust on Iron Fertilization of the Southern Ocean

    Science.gov (United States)

    Shoenfelt, E. M.; Winckler, G.; Kaplan, M. R.; Sambrotto, R.; Bostick, B. C.

    2016-12-01

    An increase in iron-containing dust flux and a more efficient biological pump in the Southern Ocean have been associated with the CO2 drawdown and global cooling of the Last Glacial Maximum (LGM). While iron (Fe) mineralogy is known to affect Fe bioavailability through its impact on Fe solubility, there are limited studies investigating the importance of Fe mineralogy in dust fluxes to the Southern Ocean, and no previous studies investigating interactions between eukaryotic phytoplankton and particulate-phase Fe in natural dusts applicable to Southern Ocean environments. Since physically weathered bedrock becomes less soluble as it becomes weathered and oxidized, we hypothesized that glacially sourced dusts would contain more Fe(II)-rich primary minerals and would be more bioavailable than dusts from areas not impacted by glaciers. We used a series of natural dusts from Patagonia as the sole Fe source in incubation experiments with the model diatom Phaeodactylum tricornutum, and evaluated Fe bioavailability using culture growth rates, cell density, and variable fluorescence. Monod curves were also used to evaluate the efficiency of the different particulates as sources of nutrient Fe. Using these Monod curves fit to growth rates plotted against particulate Fe concentrations, we observed that 1) Fe(II)-rich primary silicates were significantly more effective as an Fe source to diatoms than Fe(III)-rich oxides, that 2) Fe(II) content itself was responsible for the difference in Fe bioavailability/efficiency of the Fe nutrient source, and that 3) surface interactions with the particulates were important. In an effort to explore the possibility that Fe mineralogy impacted Fe bioavailability in past oceans, we will present our hypotheses regarding productivity and Fe mineralogy/bioavailability through the last glacial cycle.

  13. Continuous Strip Reduction Test Simulating Tribological Conditions in Ironing

    DEFF Research Database (Denmark)

    Üstünyagiz, Esmeray; Nielsen, Chris Valentin; Christiansen, Peter

    2017-01-01

    materials, surface roughnesses, normal pressure, sliding length, sliding speed, interface temperature and lubrication. This paper proposes a new Strip Reduction Test (SRT) for industrial ironing processes that is capable of replicating the highly severe tribological conditions that are experienced during...

  14. Millennial-scale iron fertilization of the eastern equatorial Pacific over the past 100,000 years

    Science.gov (United States)

    Loveley, Matthew R.; Marcantonio, Franco; Wisler, Marilyn M.; Hertzberg, Jennifer E.; Schmidt, Matthew W.; Lyle, Mitchell

    2017-10-01

    The eastern equatorial Pacific Ocean plays a crucial role in global climate, as it is a substantial source of CO2 to the atmosphere and accounts for a significant portion of global new export productivity. Here we present a 100,000-year sediment core from the eastern equatorial Pacific, and reconstruct dust flux, export productivity and bottom-water oxygenation using excess-230Th-derived fluxes of 232Th and barium, and authigenic uranium concentrations, respectively. We find that during the last glacial period (71,000 to 41,000 years ago), increased delivery of dust to the eastern equatorial Pacific was coeval with North Atlantic Heinrich stadial events. Millennial-scale pulses of increased dust flux coincided with episodes of heightened biological productivity, suggesting that dissolution of dust released iron that promoted ocean fertilization. We also find that periods of low atmospheric CO2 concentrations were associated with suboxic conditions and increased storage of respired carbon in the deep eastern equatorial Pacific. Increases in CO2 concentrations during the deglaciation are coincident with increases in deep Pacific and Southern Ocean water oxygenation levels. We suggest that deep-ocean ventilation was a primary control on CO2 outgassing in this region, with superimposed pulses of high productivity providing a negative feedback.

  15. Rapid bacterial mineralization of organic carbon produced during a phytoplankton bloom induced by natural iron fertilization in the Southern Ocean

    Science.gov (United States)

    Obernosterer, Ingrid; Christaki, Urania; Lefèvre, Dominique; Catala, Philippe; Van Wambeke, France; Lebaron, Philippe

    2008-03-01

    The response of heterotrophic bacteria ( Bacteria and Archaea) to the spring phytoplankton bloom that occurs annually above the Kerguelen Plateau (Southern Ocean) due to natural iron fertilization was investigated during the KErguelen Ocean and Plateau compared Study (KEOPS) cruise in January-February 2005. In surface waters (upper 100 m) in the core of the phytoplankton bloom, heterotrophic bacteria were, on an average, 3-fold more abundant and revealed rates of production ([ 3H] leucine incorporation) and respiration (bacterial metabolic activities were attributable to high-nucleic-acid-containing cells that dominated (≈80% of total cell abundance) the heterotrophic bacterial community associated with the phytoplankton bloom. Bacterial growth efficiencies varied between 14% and 20% inside the bloom and were bacterial activity, due to the stimulation by phytoplankton-derived dissolved organic matter. Within the Kerguelen bloom, bacterial carbon demand accounted for roughly 45% of gross community production. These results indicate that heterotrophic bacteria processed a significant portion of primary production, with most of it being rapidly respired.

  16. SATDSK: a numerical simulation of the magnetic field due to saturated iron in cyclotron poletips

    International Nuclear Information System (INIS)

    McNeilly, G.S.

    1979-10-01

    SATDSK is a computer program, written in FORTRAN, which calculates the median plane magnetic field due to fully saturated iron poletips. Optionally, SATDSK calculates the magnetic field due to disks of magnetic charge, which can simulate the effect of holes in the iron poletip, or circular trim rods embedded in the poletip. SATDSK is intended for poletip geometries that are both symmetric about the median plane, and have azimuthal sector symmetry. Thus, the program is primarily designed to simulate the magnetic field due to iron poletips in superconducting cyclotrons

  17. Effects of simulated weightlessness on meiosis. Fertilization, and early development in mice

    Science.gov (United States)

    Wolgemuth, D. J.

    1986-01-01

    The initial goal was to construct a clinostat which could support mammalian cell culture. The clinostat was selected as a means by which to simulate microgravity conditions within the laboratory, by constant re-orientation of cells with respect to the gravity vector. The effects of this simulated microgravity on in-vitro meiotic maturation of oocytes, using mouse as the model system, was investigated. The effects of clinostat rotation on fertilization in-vitro was then examined. Specific endpoints included examining the timely appearance of male and female pronuclei (indicating fertilization) and the efficiency of extrusion of the second polar body. Particular attention was paid to detecting anomalies of fertilization, including parthenogenetic activation and multiple pronuclei. Finally, for the preliminary studies on mouse embryogenesis, a key feature of the clinostat was modified, that of the position of the cells during rotation. A means was found to immobilize the cells during the clinostat reotation, permitting the cells to remain at the axis of rotation yet not interfering with cellular development.

  18. Comparing the performance of 11 crop simulation models in predicting yield response to nitrogen fertilization

    DEFF Research Database (Denmark)

    Salo, T J; Palosuo, T; Kersebaum, K C

    2016-01-01

    Eleven widely used crop simulation models (APSIM, CERES, CROPSYST, COUP, DAISY, EPIC, FASSET, HERMES, MONICA, STICS and WOFOST) were tested using spring barley (Hordeum vulgare L.) data set under varying nitrogen (N) fertilizer rates from three experimental years in the boreal climate of Jokioinen......, Finland. This is the largest standardized crop model inter-comparison under different levels of N supply to date. The models were calibrated using data from 2002 and 2008, of which 2008 included six N rates ranging from 0 to 150 kg N/ha. Calibration data consisted of weather, soil, phenology, leaf area...... ranged from 170 to 870 kg/ha. During the test year 2009, most models failed to accurately reproduce the observed low yield without N fertilizer as well as the steep yield response to N applications. The multi-model predictions were closer to observations than most single-model predictions, but multi...

  19. Iron

    DEFF Research Database (Denmark)

    Hansen, Jakob Bondo; Moen, I W; Mandrup-Poulsen, T

    2014-01-01

    and discuss recent evidence, suggesting that iron is a key pathogenic factor in both type 1 and type 2 diabetes with a focus on inflammatory pathways. Pro-inflammatory cytokine-induced β-cell death is not fully understood, but may include iron-induced ROS formation resulting in dedifferentiation by activation...... of transcription factors, activation of the mitochondrial apoptotic machinery or of other cell death mechanisms. The pro-inflammatory cytokine IL-1β facilitates divalent metal transporter 1 (DMT1)-induced β-cell iron uptake and consequently ROS formation and apoptosis, and we propose that this mechanism provides...

  20. Melting of iron at the Earth's core conditions by molecular dynamics simulation

    Directory of Open Access Journals (Sweden)

    Y. N. Wu

    2011-09-01

    Full Text Available By large scale molecular dynamics simulations of solid-liquid coexistence, we have investigated the melting of iron under pressures from 0 to 364 GPa. The temperatures of liquid and solid regions, and the pressure of the system are calculated to estimate the melting point of iron. We obtain the melting temperature of iron is about 6700±200K under the inner-outer core boundary, which is in good agreement with the result of Alfè et al. By the pair analysis technique, the microstructure of liquid iron under higher pressures is obviously different from that of lower pressures and ambient condition, indicating that the pressure-induced liquid-liquid phase transition may take place in iron melts.

  1. Iron

    Science.gov (United States)

    ... Share: Search the ODS website Submit Search NIH Office of Dietary Supplements Consumer Datos en español Health ... eating a variety of foods, including the following: Lean meat, seafood, and poultry. Iron-fortified breakfast cereals ...

  2. Monte Carlo simulation for the estimation of iron in human whole ...

    Indian Academy of Sciences (India)

    The simulation shows that theobtained results are in good agreement with experimental data, and better than the theoretical XCOM values. The study indicates that MCNP simulation is an excellent tool to estimate the iron concentration in the blood samples. The MCNP code can also be utilized to estimate other trace ...

  3. Limited Dissolved Phosphorus Runoff Losses from Layered Double Hydroxide and Struvite Fertilizers in a Rainfall Simulation Study.

    Science.gov (United States)

    Everaert, Maarten; da Silva, Rodrigo C; Degryse, Fien; McLaughlin, Mike J; Smolders, Erik

    2018-03-01

    The enrichment of P in surface waters has been linked to P runoff from agricultural fields amended with fertilizers. Novel slow-release mineral fertilizers, such as struvite and P-exchanged layered double hydroxides (LDHs), have received increasing attention for P recycling from waste streams, and these fertilizers may potentially reduce the risk of runoff losses. Here, a rainfall simulation experiment was performed to evaluate P runoff associated with the application of recycled slow-release fertilizers relative to that of a soluble fertilizer. Monoammonium phosphate (MAP), struvite, and LDH granular fertilizers were broadcasted at equal total P doses on soil packed in trays (5% slope) and covered with perennial ryegrass ( L.). Four rainfall simulation events of 30 min were performed at 1, 5, 15, and 30 d after the fertilizer application. Runoff water from the trays was collected, filtered, and analyzed for dissolved P. For the MAP treatment, P runoff losses were high in the first two rain events and leveled off in later rain events. In total, 42% of the applied P in the MAP treatment was lost due to runoff. In the slow-release fertilizer treatments, P runoff losses were limited to 1.9 (struvite) and 2.4% (LDH) of the applied doses and were more similar over the different rain events. The use of these novel P fertilizer forms could be beneficial in areas with a high risk of surface water eutrophication and a history of intensive fertilization. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. A spectral X-ray CT simulation study for quantitative determination of iron

    Science.gov (United States)

    Su, Ting; Kaftandjian, Valérie; Duvauchelle, Philippe; Zhu, Yuemin

    2018-06-01

    Iron is an essential element in the human body and disorders in iron such as iron deficiency or overload can cause serious diseases. This paper aims to explore the ability of spectral X-ray CT to quantitatively separate iron from calcium and potassium and to investigate the influence of different acquisition parameters on material decomposition performance. We simulated spectral X-ray CT imaging of a PMMA phantom filled with iron, calcium, and potassium solutions at various concentrations (15-200 mg/cc). Different acquisition parameters were considered, such as the number of energy bins (6, 10, 15, 20, 30, 60) and exposure factor per projection (0.025, 0.1, 1, 10, 100 mA s). Based on the simulation data, we investigated the performance of two regularized material decomposition approaches: projection domain method and image domain method. It was found that the former method discriminated iron from calcium, potassium and water in all cases and tended to benefit from lower number of energy bins for lower exposure factor acquisition. The latter method succeeded in iron determination only when the number of energy bins equals 60, and in this case, the contrast-to-noise ratios of the decomposed iron images are higher than those obtained using the projection domain method. The results demonstrate that both methods are able to discriminate and quantify iron from calcium, potassium and water under certain conditions. Their performances vary with the acquisition parameters of spectral CT. One can use one method or the other to benefit better performance according to the data available.

  5. Hydrogen production from natural gas using an iron-based chemical looping technology: Thermodynamic simulations and process system analysis

    International Nuclear Information System (INIS)

    Kathe, Mandar V.; Empfield, Abbey; Na, Jing; Blair, Elena; Fan, Liang-Shih

    2016-01-01

    Highlights: • Design of iron-based chemical looping process using moving bed for H_2 from CH_4. • Auto-thermal operation design using thermodynamic rationale for 90% carbon capture. • Cold gas efficiency: 5% points higher than Steam Methane Reforming baseline case. • Net thermal efficiency: 6% points higher than Steam Methane Reforming baseline case. • Sensitivity analysis: Energy recovery scheme, operating pressure, no carbon capture. - Abstract: Hydrogen (H_2) is a secondary fuel derived from natural gas. Currently, H_2 serves as an important component in refining operations, fertilizer production, and is experiencing increased utilization in the transportation industry as a clean combustion fuel. In recent years, industry and academia have focused on developing technology that reduces carbon emissions. As a result, there has been an increase in the technological developments for producing H_2 from natural gas. These technologies aim to minimize the cost increment associated with clean energy production. The natural gas processing chemical looping technology, developed at The Ohio State University (OSU), employs an iron-based oxygen carrier and a novel gas–solid counter-current moving bed reactor for H_2 production. Specifically, this study examines the theoretical thermodynamic limits for full conversion of natural gas through iron-based oxygen carrier reactions with methane (CH_4), by utilizing simulations generated with ASPEN modeling software. This study initially investigates the reducer and the oxidizer thermodynamic phase diagrams then derives an optimal auto-thermal operating condition for the complete loop simulation. This complete loop simulation is initially normalized for analysis on the basis of one mole of carbon input from natural gas. The H_2 production rate is then scaled to match that of the baseline study, using a full-scale ASPEN simulation for computing cooling loads, water requirements and net parasitic energy consumption. The

  6. Effect of Nano Iron and Solupotasse Fertilizers on Accumulation of Nutrient Elements and Quality of Two Onion (Allium cepa Cultivars

    Directory of Open Access Journals (Sweden)

    Ali Joghatay

    2015-11-01

    Full Text Available To study the effect of nano iron and solupotass on agronomic and physiological traits of two onion cultivars, a factorial experiment was conducted in complete randomized block design with 32 treatments and three replications in Joghatai of Khorasan-e- Razavi province, Iran. Treatments consisted of two onion cultivars (red, yellow and four levels (0, 1, 2, 3 kg per hectare of nano iron chelat and four levels of solupotass (0, 5, 10, 15 kg per hectare. Results showed that the effect of nano iron and solupotasse on fresh weight, dry weight, pyrovic acid and macro element (N, P, S contents were significant at %1 levels. Application nano iron, solupotasse to red onion cultivar increased dry weight significantly at the %5 level. Highest onion weight was obtained by using 2 kg nano iron and 15 kg solupotasse (17.3 g. Use of nano iron and solupotasse highly increased the pyruvic acid percentage (1.07 mM. Highest rate of pyruvic acid obtained by application of 3 and 15 kg nano iron and solupotasse respectively. Application of nano iron on the sulfur and nitrogen contents of onion were significant. Use of 2 kg/ha of nano iron exhibited highest increase in these elements. Thus, soil application of 10 kg/ha solupotasse, 3 kg/ha nano iron would highly increase red onion traits mentioned above.

  7. Changes in primary productivity and chlorophyll a in response to iron fertilization in the Southern Polar Frontal Zone

    OpenAIRE

    Gervais, F.; Riebesell, Ulf; Gorbunov, MY

    2002-01-01

    EisenEx�the second in situ iron enrichment experiment in the Southern Ocean�was performed in the Atlantic sector over 3 weeks in November 2000 with the overarching goal to test the hypothesis that primary productivity in the Southern Ocean is limited by iron availability in the austral spring. Underwater irradiance, chlorophyll a (Chl a), photochemical efficiency, and primary productivity were measured inside and outside of an iron-enriched patch in order to quantify the response of phytoplan...

  8. Fertilizer source effects on phosphate and nitrate leaching through simulated golf greens

    International Nuclear Information System (INIS)

    Shuman, L.M.

    2003-01-01

    In general, more P than N leached from both field and greenhouse lysimeters. - Phosphorus and nitrogen leached from high-porosity golf greens can adversely affect surface water and groundwater quality. Greenhouse and field lysimeter experiments were carried out to determine the effects of eight fertilizer sources on P and N leaching from simulated golf greens. Phosphorus appeared in the leachate later than nitrate-N, and the highest concentrations were for the soluble 20-20-20 and the 16-25-12 starter fertilizers. The other six sources resulted in lower P concentrations. The soluble 20-20-20 and the 16-25-12 sources each resulted in 43% of the added P eluting in the leachate, whereas the others varied from 15 to 25%. For nitrate-N the lowest cumulative mass was for the controlled-release 13-13-13 and sulfur-coated urea. A higher percentage of applied P than applied N leached from both field and greenhouse lysimeters. However, the amounts of P leached for the field lysimeters were lower than for the greenhouse columns

  9. Nucleation and solidification of thin walled ductile iron - Experiments and numerical simulation

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2005-01-01

    Investigation of solidification of thin walled ductile cast iron has been performed based on experiments and numerical simulation. The experiments were based on temperature and microstructure examination. Results of the experiments have been compared with a 1-D numerical solidification model...

  10. Iron fertilization with FeEDDHA : the fate and effectiveness of FeEDDHA chelates in soil-plant systems

    NARCIS (Netherlands)

    Schenkeveld, W.D.C.

    2010-01-01

    Iron deficiency chlorosis is a nutritional disorder in plants which reduces crop yields both quantitatively and qualitatively, and causes large economic losses. It occurs world-wide, predominantly in plants grown on calcareous soils, as a result of a limited bioavailability of iron related to the

  11. On the corrosion behaviour of phosphoric irons in simulated concrete pore solution

    International Nuclear Information System (INIS)

    Sahoo, Gadadhar; Balasubramaniam, R.

    2008-01-01

    The corrosion behaviour of three phosphoric irons P 1 (Fe-0.11P-0.028C), P 2 (Fe-0.32P-0.026C) and P 3 (Fe-0.49P-0.022C) has been studied in simulated concrete pore solution (saturated Ca(OH) 2 solution) containing different chloride concentration. This has been compared with that of two commercial concrete reinforcement steels, a low carbon steel TN (Fe-0.148C-0.542Mn-0.128Si) and a microalloyed corrosion resistant steel CS (Fe-0.151C-0.088P-0.197Si-0.149Cr-0.417Cu). The beneficial aspect of phosphoric irons was revealed from potentiodynamic polarization experiments. The pitting potentials and pitting nucleation resistances for phosphoric irons and CS were higher than that for TN. Electrochemical impedance spectroscopy (EIS) studies revealed thickening and growth of passive film as a function of time in case of phosphoric irons and CS in saturated Ca(OH) 2 pore solutions without chloride and in the same solution with 0.05% Cl - and 0.1% Cl - . In case of TN, breakdown of passive film resulted in active corrosion in simulated pore solution containing 0.1% Cl - . Linear polarization resistance measurements complemented EIS results. Visual observations indicated that phosphoric iron P 3 was immune to corrosion even after 125 days of immersion in saturated Ca(OH) 2 solution containing 5% NaCl. The good corrosion resistance of phosphoric irons in simulated concrete pore solution containing chloride ions has been related to the formation of phosphate, based on ultraviolet spectrophotometric analysis and Pourbaix diagram of phosphorus-water system

  12. Biochar-organic amendment mixtures added to simulated golf greens under reduced chemical fertilization increase creeping bentgrass growth

    Science.gov (United States)

    Simulated golf greens were used to test the growth of creeping bentgrass (Agrostis stolonifera L. "007") receiving suboptimal chemical fertilization in sand based substrates amended with 15% peat (control), a commercial biochar, a commercial biochar-compost (CarbonizPN), or seven formulated biochar...

  13. Simulation of alpha decay of actinides in iron phosphate glasses by ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Dube, Charu L., E-mail: dubecharu@gmail.com; Stennett, Martin C.; Gandy, Amy S.; Hyatt, Neil C.

    2016-03-15

    Highlights: • Alpha decay of actinides in iron phosphate glasses is simulated by employing ion irradiation technique. • FTIR and Raman spectroscopic measurements confirm modification of glass network. • The depolymerisation of glass network after irradiation is attributed to synergetic effect of nuclear and electronic losses. - Abstract: A surrogate approach of ion beam irradiation is employed to simulate alpha decay of actinides in iron phosphate nuclear waste glasses. Bismuth and helium ions of different energies have been selected for simulating glass matrix modification owing to radiolysis and ballistic damage due to recoil atoms. Structural modification and change in coordination number of network former were probed by employing Reflectance Fourier-Transform Infrared (FT-IR), and Raman spectroscopies as a consequence of ion irradiation. Depolymerisation is observed in glass sample irradiated at intermediate energy of 2 MeV. Helium blisters of micron size are seen in glass sample irradiated at low helium ion energy of 30 keV.

  14. Simulation of irrigation and nitrogen fertilization management of maize under edaphic conditions of south of Havana

    International Nuclear Information System (INIS)

    Lopez Seijas, Teresa; Cid, G.; Gonzalez, F.; Jorge, Y.; Chaterlan, Y.; Giralt, E.; Rodriguez, R.; Duennas, G.

    1999-01-01

    The main objective of this work is to validate the crop simulation model STICS for the soil and climate conditions of south of Havana, especially for the water and nitrogen balances on Maize crop on Ferralitic soil, For this purpose was used all the available information from field experiments carried out in the Experimental Stations of the Irrigation and Drainage and Soil Research Institutes, both on south of Havana, The comparison between the simulation and observed values showed a good fitness for the variables related to the crop water uptake, while for the soil water content when the root water uptake flux is minimum and the soil water redistribution flux is maximum wasn't good, The soil nitrogen balance was adjusted from the optimization of the parameters related to the mineralization velocity of soil organic nitrogen, Nevertheless is necessary to complete this study involving other climate conditions and water and nitrogen managements to define the optimum strategy for irrigation and fertilization of Maize crop on the studied conditions,

  15. Balance sheet method assessment for nitrogen fertilization in winter wheat: II. alternative strategies using the CropSyst simulation model

    Directory of Open Access Journals (Sweden)

    Maria Corbellini

    2006-09-01

    Full Text Available It is important, both for farmer profit and for the environment, to correctly dose fertilizer nitrogen (N for winter wheat growth. Balance-sheet methods are often used to calculate the recommended dose of N fertilizer. Other methods are based on the dynamic simulation of cropping systems. Aim of the work was to evaluate the balance-sheet method set up by the Region Emilia-Romagna (DPI, by comparing it with the cropping systems simulation model CropSyst (CS, and with an approach based on fixed supplies of N (T. A 3-year trial was structured as a series of N fertility regimes at 3 sites (Papiano di Marsciano, Ravenna, San Pancrazio. The N-regimes were generated at each site-year as separate trials in which 3 N rates were applied: N1 (DPI, N2 (DPI+50 kg ha-1 N at spike initiation, N3 (DPI + 50 kg ha-1 N at early booting. Above ground biomass and soil data (NO3-N and water were sampled and used to calibrate CS. Doses of fertilizer N were calculated by both DPI and CS for winter wheat included in three typical rotations for Central and Northern Italy. Both these methods and method T were simulated at each site over 50 years, by using daily generated weather data. The long-term simulation allowed evaluating such alternative fertilization strategies. DPI and CS estimated comparable crop yields and N leached amounts, and both resulted better than T. Minor risk of leaching emerged for all N doses. The N2 and N3 rates allowed slightly higher crop yields than N1.

  16. Corrosion in the SCWR: insights from molecular dynamics simulations of the supercritical water - iron hydroxide interface

    Energy Technology Data Exchange (ETDEWEB)

    Kallikragas, D.; Plugatyr, A.; Svishchev, I.M., E-mail: dimitrioskallikragas@trentu.ca [Trent University, Peterborough, Ontario (Canada)

    2013-07-01

    The adsorption properties of supercritical water confined between parallel iron (II) hydroxide surfaces were determined through molecular dynamics simulations. Simulations were conducted at temperatures and water densities typically found in the heat transport system of the supercritical water cooled nuclear reactor (SCWR). Surface water layer densities were compared to those of the bulk water. Adsorption coverage was calculated as a function of the number of waters per surface OH group. Images of the water molecules configurations are provided along with the density profile of the adsorption layer. The observed localized adsorption and surface clustering of supercritical water, would likely produce more localized corrosion phenomena in the water bearing components of the SCWR. (author)

  17. FTIR spectra and properties of iron borophosphate glasses containing simulated nuclear wastes

    Science.gov (United States)

    Liao, Qilong; Wang, Fu; Chen, Kuiru; Pan, Sheqi; Zhu, Hanzhen; Lu, Mingwei; Qin, Jianfa

    2015-07-01

    30 wt.% simulated nuclear wastes were successfully immobilized by B2O3-doped iron phosphate base glasses. The structure and thermal stability of the prepared wasteforms were characterized by Fourier transform infrared spectroscopy and differential thermal analysis, respectively. The subtle structural variations attributed to different B2O3 doping modes have been discussed in detail. The results show that the thermal stability and glass forming tendency of the iron borophosphate glass wasteforms are faintly affected by different B2O3 doping modes. The main structural networks of iron borophosphate glass wasteforms are PO43-, P2O74-, [BO4] groups. Furthermore, for the wasteform prepared by using 10B2O3-36Fe2O3-54P2O5 as base glass, the distributions of Fe-O-P bonds, [BO4], PO43- and P2O74- groups are optimal. In general, the dissolution rate (DR) values of the studied iron borophosphate wasteforms are about 10-8 g cm-2 min-1. The obtained conclusions can offer some useful information for the disposal of high-level radioactive wastes using boron contained phosphate glasses.

  18. Application of Circuit Simulation Method for Differential Modeling of TIM-2 Iron Uptake and Metabolism in Mouse Kidney Cells

    Directory of Open Access Journals (Sweden)

    Zhijian eXie

    2013-06-01

    Full Text Available Circuit simulation is a powerful methodology to generate differential mathematical models. Due to its highly accurate modelling capability, circuit simulation can be used to investigate interactions between the parts and processes of a cellular system. Circuit simulation has become a core technology for the field of electrical engineering, but its application in biology has not yet been fully realized. As a case study for evaluating the more advanced features of a circuit simulation tool called Advanced Design System (ADS, we collected and modeled laboratory data for iron metabolism in mouse kidney cells for a H ferritin (HFt receptor, T cell immunoglobulin and mucin domain-2 (TIM-2. The internal controlling parameters of TIM-2 associated iron metabolism were extracted and the ratios of iron movement among cellular compartments were quantified by ADS. The differential model processed by circuit simulation demonstrated a capability to identify variables and predict outcomes that could not be readily measured by in vitro experiments. For example, an initial rate of uptake of iron-loaded HFt was 2.17 pmol per million cells. TIM-2 binding probability with iron-loaded HFt was 16.6%. An average of 8.5 minutes was required for the complex of TIM-2 and iron-loaded HFt to form an endosome. The endosome containing HFt lasted roughly 2 hours. At the end of endocytosis, about 28% HFt remained intact and the rest was degraded. Iron released from degraded HFt was in the labile iron pool (LIP and stimulated the generation of endogenous HFt for new storage. Both experimental data and the model showed that TIM-2 was not involved in the process of iron export. The extracted internal controlling parameters successfully captured the complexity of TIM-2 pathway and the use of circuit simulation-based modeling across a wider range of cellular systems is the next step for validating the significance and utility of this method.

  19. Effects of simulated root herbivory and fertilizer application on growth and biomass allocation in the clonal perennialSolidago canadensis.

    Science.gov (United States)

    Schmid, B; Miao, S L; Bazzaz, F A

    1990-08-01

    Compensatory growth in response to simulated belowground herbivory was studied in the old-field clonal perennialSolidago canadensis. We grew rootpruned plants and plants with intact root systems in soil with or without fertilizer. For individual current shoots (aerial shoot with rhizome and roots) and for whole clones the following predictions were tested: a) root removal is compensated by increased root growth, b) fertilizer application leads to increased allocation to aboveground plant organs and increased leaf turnover, c) effects of fertilizer application are reduced in rootpruned plants. When most roots (90%) were removed current shoots quickly restored equilibrium between above-and belowground parts by compensatory belowground growth whereas the whole clone responded with reduced aboveground growth. This suggests that parts of a clone which are shared by actively growing shoots act as a buffer that can be used as source of material for compensatory growth in response to herbivory. Current shoots increased aboveground mass and whole clones reduced belowground mass in response to fertilizer application, both leading to increased allocation to aboverground parts. Also with fertilizer application both root-pruned and not root-pruned plants increased leaf and shoot turnover. Unfertilized plants, whether rootpruned or not, showed practically no aboveground growth and very little leaf and shoot turnover. Effects of root removal were as severe or more severe under conditions of high as under conditions of low nutrients, suggesting that negative effects of belowground herbivory are not ameliorated by abundant nutrients. Root removal may negate some effects of fertilizer application on the growth of current shoots and whole clones.

  20. Presentation of a model simulating the response of lakes to fertilizations to reduce radiocesium levels in fish

    International Nuclear Information System (INIS)

    Hakanson, L.; Ottosson, F.; Abrahamsson, O.; Johansson, T.

    1998-01-01

    Lake fertilization is a potential remedy for toxic contamination in lakes with low productivity, which are known to be sensitive to, e.g. radionuclides, metals and organic toxins. This study presents a model to plan the duration and predict the outcome of fertilization in lakes. Several methods of lake fertilization have been used in field experiments: (1) Lake and wetland liming using 'mixed' lime with added phosphorus; (2) treatment with commercial fertilizers; and (3) using effluents (containing phosphorus) from fish farms. This model is basically a dynamic model using differential equations to handle fluxes, amounts and concentrations. It also includes several empirical relationships, because the model is meant to be used in practice and the driving variables should be few and readily available, like catchment and lake morphometric data. The model is primarily intended to be used as a sub-model predicting realistic changes in phosphorus and potassium concentrations and in lake pH caused by these remedial measures within the framework of a more extensive lake model for radiocesium. It is, however, meant to be based on the fundamental processes regulating phosphorus fluxes in lakes, and could be of interest also in contexts other than radioecology. It is driven by the amount of fertilizer added to the lake and the month of treatment. The consequences for the spread, biological uptake and concentrations of radiocesium are also discussed and simulated. The phosphorus model is, and must be, easy to handle since all the input data should be derived either from maps or from regular monitoring programs. In this paper, the model is presented and calibrations are examined. The results of the calibrations indicate that the model should be useful for managers to optimise lake fertilization, e.g. in contexts of lake radioecology where the benefits and drawbacks of different remedial strategies are evaluated (multi-attribute analysis). (Copyright (c) 1998 Elsevier Science B

  1. Molecular dynamics simulations of quasi-brittle crack development in iron

    Energy Technology Data Exchange (ETDEWEB)

    Borodin, V.A., E-mail: borodin@dni.polin.kiae.su [Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe (Germany); NRC Kurchatov Institute, Kurchatov Sq. 1, 123182 Moscow (Russian Federation); Vladimirov, P.V., E-mail: Pavel.Vladimirov@kit.edu [Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe (Germany)

    2011-08-31

    The paper presents the results of molecular dynamics (MD) simulations of three-dimensional kinetics of micro-crack propagation in alpha-iron and the accompanying lattice transformations at the crack tips. We show that crack initiation on {l_brace}0 0 1{r_brace} planes in iron is preceded with the emission of compact slip bands from the pre-crack tips, in agreement with the predictions of the earlier quasi-two-dimensional simulations. The application of Voronoi decomposition technique for atomic short-range order processing has allowed us to clarify the kinetics of structural transformations at the tips of nucleating and propagating cracks for three most common systems of crack propagation in iron. It is demonstrated that the compact slip bands emanating from the crack tips not only accompany crack nucleation, but remain an essential feature of the crack propagation on {l_brace}0 0 1{r_brace} planes. Due to the strong coupling between the crack tip and slip band propagation, the crack propagation can be limited by slip band interaction with microstructural obstacles, abundantly created in ferritic-martensitic steels in radiation environment of nuclear facilities.

  2. Effect of Freezing and Thawing on Activity of Cu and Zn in Black Soil of Northeast China Under Simulated Fertilization Using Pig Manure

    Directory of Open Access Journals (Sweden)

    XU Cong-long

    2015-06-01

    Full Text Available With the development of large-scale farms and the addition of Cu and Zn in feed additives, high Cu and Zn contents in feces of livestock and poultry occurred, and may cause soil pollution of the heavy metal especially Cu and Zn by livestock and poultry manure fertilization. Both fertilization of livestock and poultry manure and freeze-thaw action can alter the activity of heavy metals in soil, and furthermore change the environmental effect of heavy metals in soil. This paper aimed at the influence of freezing and thawing on the activities of Cu and Zn (exchangeable and carbonate in black soil of Northeast China under pig manure fertilization according to the northeast climate characteristics through laboratory simulation. The results showed that the contents of exchangeable Cu and Zn significantly increased and that of carbonate Cu and Zn slightly decreased under pig manure fertilization initial stage comparing with the control without fertilizer. The contents of exchangeable Cu and Zn slightly increased and that of carbonate Cu and Zn decreased for the higher fertilization comparing with lower fertilization. The contents of exchangeable Cu and Zn decreased and that of carbonate Cu and Zn significantly increased with the extension of fertilization time (one month compared with the early fertilization (one week. Moreover, the contents of exchangeable Cu and Zn under higher fertilization were all higher than that under lower fertilization, on the contrary, the contents of carbonate Cu and Zn under higher fertilization all were lower than that under lower fertilization. The contents of exchangeable and carbonate Cu and Zn all increased obviously with the freezing and thawing temperature decreased, and the contents of Cu and Zn for higher fertilization were higher than that for lower fertilization. In conclusion, the activities of Cu and Zn in black soil were disturbed by both pig manure with different fertilization amounts and fertilization

  3. Electrochemical behaviour of iron and AISI 304 stainless steel in simulated acid rain solution

    Energy Technology Data Exchange (ETDEWEB)

    Pilic, Zora; Martinovic, Ivana [Mostar Univ. (Bosnia and Herzegovina). Dept. of Chemistry

    2016-10-15

    The growth mechanism and properties of the oxide films on iron and AISI 304 stainless steel were studied in simulated acid rain (pH 4.5) by means of electrochemical techniques and atomic absorption spectrometry. The layer-pore resistance model was applied to explain a potentiodynamic formation of surface oxides. It was found that the growth of the oxide film on iron takes place by the low-field migration mechanism, while that on the stainless steel takes place by the high-field mechanism. Kinetic parameters were determined. Impedance measurements revealed that Fe surface film has no protective properties at the open circuit potential, while the resistance of stainless steel oxide film is very high. The concentration of the metallic ions released into solution and measured by atomic absorption spectroscopy was in accordance with the results obtained from the electrochemical techniques.

  4. Export production in the subarctic North Pacific over the last 800 kyrs: No evidence for iron fertilization?

    Science.gov (United States)

    Kienast, S.S.; Hendy, I.L.; Crusius, J.; Pedersen, Thomas F.; Calvert, S.E.

    2004-01-01

    The subarctic North Pacific is a high nitrate-low chlorophyll (HNLC) region, where phytoplankton growth rates, especially those of diatoms, are enhanced when micro-nutrient Fe is added. Accordingly, it has been suggested that glacial Fe-laden dust might have increased primary production in this region. This paper reviews published palaeoceanographic records of export production over the last 800 kyrs from the open North Pacific (north of ???35??N). We find different patterns of export production change over time in the various domains of the North Pacific (NW and NE subarctic gyres, the marginal seas and the transition zone). However, there is no compelling evidence for an overall increase in productivity during glacials in the subarctic region, challenging the paradigm that dust-born Fe fertilization of this region has contributed to the glacial draw down of atmospheric CO2. Potential reasons for the lack of increased glacial export production include the possibility that Fe-fertilization rapidly drives the ecosystem towards limitation by another nutrient. This effect would have been exacerbated by an even more stable mixed layer compared to today. ?? The Oceanographic Society of Japan.

  5. Simulation of magnetic hysteresis loops and magnetic Barkhausen noise of α-iron containing nonmagnetic particles

    International Nuclear Information System (INIS)

    Li, Yi; Li, Qiulin; Liu, Wei; Xu, Ben; Hu, Shenyang; Li, Yulan

    2015-01-01

    The magnetic hysteresis loops and Barkhausen noise of a single α-iron with nonmagnetic particles are simulated to investigate into the magnetic hardening due to Cu-rich precipitates in irradiated reactor pressure vessel (RPV) steels. Phase field method basing Landau-Lifshitz-Gilbert (LLG) equation is used for this simulation. The results show that the presence of the nonmagnetic particle could result in magnetic hardening by making the nucleation of reversed domains difficult. The coercive field is found to increase, while the intensity of Barkhausen noise voltage is decreased when the nonmagnetic particle is introduced. Simulations demonstrate the impact of nucleation field of reversed domains on the magnetization reversal behavior and the magnetic properties

  6. Modelling phosphorus (P), sulphur (S) and iron (Fe) interactions during the simulation of anaerobic digestion processes

    DEFF Research Database (Denmark)

    Flores-Alsina, Xavier; Solon, Kimberly; Kazadi-Mbamba, Christian

    2015-01-01

    This paper examines the effects of different model formulations when describing sludge stabilization processes in wastewater treatment plants by the Anaerobic Digestion Model No. 1 (ADM1). The proposed model extensions describe the interactions amongst phosphorus (P), sulfur (S), iron (Fe......) and their potential effect on total biogas production (CO2, CH4, H2 and H2S). The ADM1 version, implemented in the plant-wide context provided by the Benchmark Simulation Model No. 2 (BSM2), is used as the basic platform (A0). Four (A1 – A4) different model extensions are implemented, simulated and evaluated......2) as the electron donor. Finally, the last evaluated approach (A4) is based on accounting for Multiple Mineral Precipitation. The ADM1 thereby switches from a 2-phase (aqueous-gas) to a 3-phase (aqueous-gas-solid) system. Simulation results show that the implementations of A1 and A2 lead...

  7. Iron biofortification of wheat grains through integrated use of organic and chemical fertilizers in pH affected calcareous soil.

    Science.gov (United States)

    Ramzani, Pia Muhammad Adnan; Khalid, Muhammad; Naveed, Muhammad; Ahmad, Rashid; Shahid, Muhammad

    2016-07-01

    Incidence of iron (Fe) deficiency in human populations is an emerging global challenge. This study was conducted to evaluate the potential of iron sulphate combined with biochar and poultry manure for Fe biofortification of wheat grains in pH affected calcareous soil. In first two incubation studies, rates of sulfur (S) and Fe combined with various organic amendments for lowering pH and Fe availability in calcareous soil were optimized. In pot experiment, best rate of Fe along with biochar (BC) and poultry manure (PM) was evaluated for Fe biofortification of wheat in normal and S treated low pH calcareous soil. Fe applied with BC provided fair increase in root-shoot biomass and photosynthesis up to 79, 53 and 67%, respectively in S treated low pH soil than control. Grain Fe and ferritin concentration was increased up to 1.4 and 1.2 fold, respectively while phytate and polyphenol was decreased 35 and 44%, respectively than control in treatment where Fe was applied with BC and S. In conclusion, combined use of Fe and BC could be an effective approach to improve growth and grain Fe biofortification of wheat in pH affected calcareous soil. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  8. Determination of iron, nickel, and chromium in the Masurca simulation rods

    International Nuclear Information System (INIS)

    Brigaudeau, M.; Pierdet, S.

    1969-01-01

    A method has been developed for determining the iron, nickel and chromium content of sintered ternary oxide rods designed to simulate structural elements in the reactor Masurca. During this work a calculation was made of the conditional constant of the Fe-EDTA complex in a formic buffer solution, and of that, of the Ni-EDTA complex in an ammoniacal buffer. From these two values it appears that it is not possible to carry out the iron and nickel determinations with a standard EDTA solution when these two elements are present simultaneously. That is the reason for which, in this case, a separation of the Fe and Ni is carried out in 8 N HCl solution on an anion exchange resin. Each element is then dosed by titricolorimetry. Chromium is determined by the same technique without prior separation. The reproducibility of the method has been calculated for each of the three elements. The relative accuracy is: 0.58 per cent for the iron; 1.41 per cent for the nickel; 0.39 per cent for the chromium. (authors) [fr

  9. Chemical evaluation of HBED/Fe(3+) and the novel HJB/Fe(3+) chelates as fertilizers to alleviate iron chlorosis.

    Science.gov (United States)

    López-Rayo, Sandra; Hernández, Diana; Lucena, Juan J

    2009-09-23

    Iron chelates such as ethylenediamine-N,N'-bis(2-hydroxyphenylacetic) acid (o,o-EDDHA) and their analogues are the most efficient soil fertilizers to treat iron chlorosis in plants growing in calcareous soil. A new chelating agent, HJB (N,N'-bis(2-hydroxy-5-methylphenyl)ethylendiamine-N,N'-diacetic acid) may be an alternative to o,o-EDDHA since its synthesis yields a purer product, but its chemical behavior and efficiency as chlorosis corrector should be evaluated. In this research, a known analogous HBED (N,N'-bis(2-hydroxyphenyl)ethylendiamine-N,N'-diacetic acid) has also been considered. First, an ion-pair high performance liquid chromatography (HPLC) method has been tested for the HJB/Fe(3+) and HBED/Fe(3+) determination. The ability of HJB and HBED to maintain Fe in solution has been compared with respect to o,o-EDDHA. Theoretical modelization for HBED and HJB in agronomic conditions has been done after the determination of the protonation and Ca(II), Mg(II), Fe(III), and Cu(II) stability constants for HJB. Also, batch interaction experiments with soils and soil materials have been conducted. According to our results, HJB/Fe(3+) and HBED/Fe(3+) present high stability, even when competing cations (Cu(2+), Ca(2+)) are present, and have low reactivity with soils and soil components. The chelating agent HJB dissolves a higher amount of Fe than o,o-EDDHA, and it seems as effective as o,o-EDDHA in keeping Fe in solution. These results indicate that these chelates may be very efficient products to correct Fe chlorosis, and additional plant experiments should demonstrate plants' ability to assimilate Fe from HJB/Fe(3+) and HBED/Fe(3+).

  10. Improving porcine in vitro fertilization output by simulating the oviductal environment

    OpenAIRE

    Soriano-?beda, Cristina; Garc?a-V?zquez, Francisco A.; Romero-Aguirregomezcorta, Jon; Mat?s, Carmen

    2017-01-01

    Differences between the in vitro and in vivo environment in which fertilization occurs seem to play a key role in the low efficiency of porcine in vitro fertilization (IVF). This work proposes an IVF system based on the in vivo oviductal periovulatory environment. The combined use of an IVF medium at the pH found in the oviduct in the periovulatory stage (pHe 8.0), a mixture of oviductal components (cumulus-oocyte complex secretions, follicular fluid and oviductal periovulatory fluid, OFCM) a...

  11. Theory, simulation and experimental results of the acoustic detection of magnetization changes in superparamagnetic iron oxide

    Directory of Open Access Journals (Sweden)

    Borgert Jörn

    2011-06-01

    Full Text Available Abstract Background Magnetic Particle Imaging is a novel method for medical imaging. It can be used to measure the local concentration of a tracer material based on iron oxide nanoparticles. While the resulting images show the distribution of the tracer material in phantoms or anatomic structures of subjects under examination, no information about the tissue is being acquired. To expand Magnetic Particle Imaging into the detection of soft tissue properties, a new method is proposed, which detects acoustic emissions caused by magnetization changes in superparamagnetic iron oxide. Methods Starting from an introduction to the theory of acoustically detected Magnetic Particle Imaging, a comparison to magnetically detected Magnetic Particle Imaging is presented. Furthermore, an experimental setup for the detection of acoustic emissions is described, which consists of the necessary field generating components, i.e. coils and permanent magnets, as well as a calibrated microphone to perform the detection. Results The estimated detection limit of acoustic Magnetic Particle Imaging is comparable to the detection limit of magnetic resonance imaging for iron oxide nanoparticles, whereas both are inferior to the theoretical detection limit for magnetically detected Magnetic Particle Imaging. Sufficient data was acquired to perform a comparison to the simulated data. The experimental results are in agreement with the simulations. The remaining differences can be well explained. Conclusions It was possible to demonstrate the detection of acoustic emissions of magnetic tracer materials in Magnetic Particle Imaging. The processing of acoustic emission in addition to the tracer distribution acquired by magnetic detection might allow for the extraction of mechanical tissue parameters. Such parameters, like for example the velocity of sound and the attenuation caused by the tissue, might also be used to support and improve ultrasound imaging. However, the method

  12. Impact of the natural Fe-fertilization on the magnitude, stoichiometry and efficiency of particulate biogenic silica, nitrogen and iron export fluxes

    Science.gov (United States)

    Lemaitre, N.; Planquette, H.; Dehairs, F.; van der Merwe, P.; Bowie, A. R.; Trull, T. W.; Laurenceau-Cornec, E. C.; Davies, D.; Bollinger, C.; Le Goff, M.; Grossteffan, E.; Planchon, F.

    2016-11-01

    The Kerguelen Plateau is characterized by a naturally Fe-fertilized phytoplankton bloom that extends more than 1000 km downstream in the Antarctic Circumpolar Current. During the KEOPS2 study, in austral spring, we measured particulate nitrogen (PN), biogenic silica (BSi) and particulate iron (PFe) export fluxes in order to investigate how the natural fertilization impacts the stoichiometry and the magnitude of export fluxes and therefore the efficiency of the biological carbon pump. At 9 stations, we estimated elemental export fluxes based on element concentration to 234Th activity ratios for particulate material collected with in-situ pumps and 234Th export fluxes (Planchon et al., 2015). This study revealed that the natural Fe-fertilization increased export fluxes but to variable degrees. Export fluxes for the bloom impacted area were compared with those of a high-nutrient, low-chlorophyll (HNLC), low-productive reference site located to the south-west of Kerguelen and which had the lowest BSi and PFe export fluxes (2.55 mmol BSi m-2 d-1 and 1.92 μmol PFem-2 d-1) and amongst the lowest PN export flux (0.73 mmol PN m-2 d-1). The impact of the Fe fertilization was the greatest within a meander of the polar front (PF), to the east of Kerguelen, with fluxes reaching 1.26 mmol PN m-2 d-1; 20.4 mmol BSi m-2 d-1 and 22.4 μmol PFe m-2 d-1. A highly productive site above the Kerguelen Plateau, on the contrary, was less impacted by the fertilization with export fluxes reaching 0.72 mmol PN m-2 d-1; 4.50 mmol BSi m-2 d-1 and 21.4 μmol PFe m-2 d-1. Our results suggest that ecosystem features (i.e. type of diatom community) could play an important role in setting the magnitude of export fluxes of these elements. Indeed, for the PF meander, the moderate productivity was sustained by the presence of large and strongly silicified diatom species while at the higher productivity sites, smaller and slightly silicified diatoms dominated. Interestingly, our results suggest that

  13. An Evaluation of Neutron Energy Spectrum Effects in Iron Based on Molecular Dynamics Displacement Cascade Simulations

    International Nuclear Information System (INIS)

    Greenwood, L.R.; Stoller, R.E.

    1998-01-01

    The results of molecular dynamics (MD) displacement cascade simulations in bcc iron have been used to obtain effective cross sections for two measures of primary damage production: (1) the number of surviving point defects expressed as a fraction of the displacements calculated using the standard secondary displacement model of Norgett, Robinson, and Torrens (NRT), and (2) the fraction of the surviving interstitials contained in clusters that formed during the cascade event. Primary knockon atom spectra for iron obtained from the SPECTER code have been used to weight these MD-based damage production cross sections in order to obtain spectrally-averaged values for several locations in commercial fission reactors and materials test reactors. An evaluation of these results indicates that neutron energy spectrum differences between the various enviromnents do not lead to significant differences between the average primary damage formation parameters. In particular, the defect production cross sections obtained for PWR and BWR neutron spectra were not significantly different. The variation of the defect production cross sections as a function of depth into the reactor pressure vessel wall is used as a sample application of the cross sections. A slight difference between the attenuation behavior of the PWR and BWR was noted; this difference could be explained by a subtle difference in the energy dependence of the neutron spectra. Overall, the simulations support the continued use of dpa as a damage correlation parameter

  14. Effects of Simulated Mobile Phone Electromagnetic Radiation on Fertilization and Embryo Development.

    Science.gov (United States)

    Chen, Hong; Qu, Zaiqing; Liu, Wenhui

    2017-04-01

    This study investigated the effects of 935-MHz electromagnetic radiation (ER) on fertilization and subsequent embryonic development in mice. Ovulating mice were irradiated at three ER intensities for 4 h/day (d) or 2 h/d for three consecutive days; the ova were then harvested for in vitro fertilization to observe the 6-h fertilization rate (6-FR), 72-h morula rate (72-MR), and 110-h blastula rate (110-BR). Compared with the control group, the 6-FR, 72-MR, and 110-BR were decreased in the low ER intensity group, but the differences were not significant; in the mid- and high-intensity ER groups, 72-MR and 110-BR in the 4 h/d and 2 h/d subgroups were decreased, showing significant differences compared with the control group. Moreover, the comparison between 4 h/d and 2 h/d subgroups showed significant differences. Mid- and high-intensity ER at 935 MHz can reduce the fertilization rate in mice, and reduce the blastulation rate, thus reducing the possibility of embryo implantation.

  15. Interconnection of nitrogen fixers and iron in the Pacific Ocean: Theory and numerical simulations

    OpenAIRE

    Dutkiewicz, S.; Ward, B. A.; Monteiro, F.; Follows, M. J.

    2012-01-01

    We examine the interplay between iron supply, iron concentrations and phytoplankton communities in the Pacific Ocean. We present a theoretical framework which considers the competition for iron and nitrogen resources between phytoplankton to explain where nitrogen fixing autotrophs (diazotrophs, which require higher iron quotas, and have slower maximum growth) can co-exist with other phytoplankton. The framework also indicates that iron and fixed nitrogen concentrations can be strongly contro...

  16. The impact of particle size, relative humidity, and sulfur dioxide on iron solubility in simulated atmospheric marine aerosols.

    Science.gov (United States)

    Cartledge, Benton T; Marcotte, Aurelie R; Herckes, Pierre; Anbar, Ariel D; Majestic, Brian J

    2015-06-16

    Iron is a limiting nutrient in about half of the world's oceans, and its most significant source is atmospheric deposition. To understand the pathways of iron solubilization during atmospheric transport, we exposed size segregated simulated marine aerosols to 5 ppm sulfur dioxide at arid (23 ± 1% relative humidity, RH) and marine (98 ± 1% RH) conditions. Relative iron solubility increased as the particle size decreased for goethite and hematite, while for magnetite, the relative solubility was similar for all of the fine size fractions (2.5-0.25 μm) investigated but higher than the coarse size fraction (10-2.5 μm). Goethite and hematite showed increased solubility at arid RH, but no difference (p > 0.05) was observed between the two humidity levels for magnetite. There was no correlation between iron solubility and exposure to SO2 in any mineral for any size fraction. X-ray absorption near edge structure (XANES) measurements showed no change in iron speciation [Fe(II) and Fe(III)] in any minerals following SO2 exposure. SEM-EDS measurements of SO2-exposed goethite revealed small amounts of sulfur uptake on the samples; however, the incorporated sulfur did not affect iron solubility. Our results show that although sulfur is incorporated into particles via gas-phase processes, changes in iron solubility also depend on other species in the aerosol.

  17. Sand-RAPG combination simulating fertile clayey soil (Part I to IV)

    International Nuclear Information System (INIS)

    Azzam, R.; El-Hady, O.A.; Lotfy, A.A.; Hegela, M.

    1983-01-01

    I. Radiation Preparation of RAPG. Sites of co-ordination and reinforcement are dominated in reclaimer ameliorator polymeric gel (RAPG). It is a modified acrylonitrile base multifunction polymer grafted upon a binder of worthless cellulosic agricultural discard. It varies chemically from non-ionic through anionic and cationic to ampholite. The hydroproperty of the gel is similarly controlled. Thus, RAPG can be tailored for any soil texture under various climatic conditions. II. Structure Stability and Maintenance. Sinai dune sand is treated with non-ionic and anionic RAPGs at rates varying from 0.05 to 0.2 wt.%. The stability increased with RAPG anionicity and application rate. The structure formed maintained three cycles of complete destruction and re-formation without significant changes in erosion index. The resistance of sand-RAPG combination to breakdown by tillage, as well as to wind and water erosion, is practically proved. This is in addition to the beneficial changes in bulk density, void ratio and microporosity, which were also achieved. III. Water Preservation. Inshas sandy soil treated by RAPG is compared with fertile clayey soil. The water-holding capacity and retention at different suctions are increased. The available water to plants in treated sand has reached 15 times that of the control, and even exceeded clay by 11%. Water losses by evaporation and leaching as well as deep percolation are all reduced to a minimum. IV. Plantation and Nutritional Status. Pepper seed germination, growth and dry matter are increased in the sand-RAPG combination relative to fertile clayey soil. The optimum rate and anionicity of RAPG are determined. This increases water-use efficiency to twice that of the fertile clayey soil. Macro- and micro-nutrient uptake have also increased. Thus, fertilizer use efficiency is increased by almost three times over that of clay. These factors lead convincingly to the conclusion that RAPG furnishes adequate conditions for sandy soil

  18. A Model to Simulate Titanium Behavior in the Iron Blast Furnace Hearth

    Science.gov (United States)

    Guo, Bao-Yu; Zulli, Paul; Maldonado, Daniel; Yu, Ai-Bing

    2010-08-01

    The erosion of hearth refractory is a major limitation to the campaign life of a blast furnace. Titanium from titania addition in the burden or tuyere injection can react with carbon and nitrogen in molten pig iron to form titanium carbonitride, giving the so-called titanium-rich scaffold or buildup on the hearth surface, to protect the hearth from subsequent erosion. In the current article, a mathematical model based on computational fluid dynamics is proposed to simulate the behavior of solid particles in the liquid iron. The model considers the fluid/solid particle flow through a packed bed, conjugated heat transfer, species transport, and thermodynamic of key chemical reactions. A region of high solid concentration is predicted at the hearth bottom surface. Regions of solid formation and dissolution can be identified, which depend on the local temperature and chemical equilibrium. The sensitivity to the key model parameters for the solid phase is analyzed. The model provides an insight into the fundamental mechanism of solid particle formation, and it may form a basic model for subsequent development to study the formation of titanium scaffold in the blast furnace hearth.

  19. Numerical simulation of ductile-brittle behaviour of cracks in aluminium and bcc iron

    International Nuclear Information System (INIS)

    Zacharopoulos, Marios

    2017-01-01

    The principal aim of the present dissertation is to investigate the role of sharp cracks on the mechanical behaviour of crystals under load at the atomic scale. The question of interest is how a pure crystal, which contains a single crack in mechanical equilibrium, deforms. Two metals were considered: aluminium, ductile at any temperature below its melting point, and iron, being transformed from ductile to brittle upon decreasing temperature below T=77 K. Cohesive forces in both metals were modeled via phenomenological n-body potentials. A (010)[001] mode I nano-crack was introduced in the perfect crystalline lattice of each of the studied metals by using appropriate displacements ascribed by anisotropic elasticity. At T=0 K, equilibrium crack configurations were obtained via energy minimization with a mixed type of boundary conditions. Both models revealed that the crack configurations remained stable under a finite range of applied stresses due to the lattice trapping effect. The present thesis proposes a novel approach to interpret the intrinsic mechanical behaviour of the two metallic systems under loading. In particular, the ductile or brittle response of a crystalline system can be determined by examining whether the lattice trapping barrier of a pre-existing crack is sufficient to cause the glide of pre-existing static dislocations on the available slip systems. Simulation results along with experimental data demonstrate that, according to the model proposed, aluminium and iron are ductile and brittle at T=0 K, respectively. (author) [fr

  20. Simulation of iron impurity in BaTiO{sub 3} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Stashans, Arvids, E-mail: arvids@utpl.edu.e [Grupo de Fisicoquimica de Materiales, Instituto de Quimica Aplicada, Universidad Tecnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador); Castillo, Darwin [Grupo de Fisicoquimica de Materiales, Instituto de Quimica Aplicada, Universidad Tecnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador); Escuela de Electronica y Telecomunicaciones, Universidad Tecnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador)

    2009-05-01

    Iron-doped barium titanate (BaTiO{sub 3}) has been simulated taking into account cubic and tetragonal crystallographic lattices of the crystal. A quantum-chemical method based on the Hartree-Fock formalism has been used throughout the study. The calculated equilibrium structures of Fe-doped crystals reveal the defect-inward displacements of the Ti and O atoms whereas the shifts for the Ba atoms are encountered to be away with respect to the Fe impurity. According to the analysis of electron density population and electron band structure it is found that some unusual chemical bonding might take place between the Fe atom and its six adjacent O atoms. The role of Fe impurity in the ferroelectric polarization of the tetragonal BaTiO{sub 3} crystal has been discussed too.

  1. Simulation of iron impurity in BaTiO3 crystals

    International Nuclear Information System (INIS)

    Stashans, Arvids; Castillo, Darwin

    2009-01-01

    Iron-doped barium titanate (BaTiO 3 ) has been simulated taking into account cubic and tetragonal crystallographic lattices of the crystal. A quantum-chemical method based on the Hartree-Fock formalism has been used throughout the study. The calculated equilibrium structures of Fe-doped crystals reveal the defect-inward displacements of the Ti and O atoms whereas the shifts for the Ba atoms are encountered to be away with respect to the Fe impurity. According to the analysis of electron density population and electron band structure it is found that some unusual chemical bonding might take place between the Fe atom and its six adjacent O atoms. The role of Fe impurity in the ferroelectric polarization of the tetragonal BaTiO 3 crystal has been discussed too.

  2. Spin-lattice dynamics simulation of external field effect on magnetic order of ferromagnetic iron

    Directory of Open Access Journals (Sweden)

    C. P. Chui

    2014-03-01

    Full Text Available Modeling of field-induced magnetization in ferromagnetic materials has been an active topic in the last dozen years, yet a dynamic treatment of distance-dependent exchange integral has been lacking. In view of that, we employ spin-lattice dynamics (SLD simulations to study the external field effect on magnetic order of ferromagnetic iron. Our results show that an external field can increase the inflection point of the temperature. Also the model provides a better description of the effect of spin correlation in response to an external field than the mean-field theory. An external field has a more prominent effect on the long range magnetic order than on the short range counterpart. Furthermore, an external field allows the magnon dispersion curves and the uniform precession modes to exhibit magnetic order variation from their temperature dependence.

  3. Magnon and phonon dispersion, lifetime, and thermal conductivity of iron from spin-lattice dynamics simulations

    Science.gov (United States)

    Wu, Xufei; Liu, Zeyu; Luo, Tengfei

    2018-02-01

    In recent years, the fundamental physics of spin-lattice (e.g., magnon-phonon) interaction has attracted significant experimental and theoretical interests given its potential paradigm-shifting impacts in areas like spin-thermoelectrics, spin-caloritronics, and spintronics. Modelling studies of the transport of magnons and phonons in magnetic crystals are very rare. In this paper, we use spin-lattice dynamics (SLD) simulations to model ferromagnetic crystalline iron, where the spin and lattice systems are coupled through the atomic position-dependent exchange function, and thus the interaction between magnons and phonons is naturally considered. We then present a method combining SLD simulations with spectral energy analysis to calculate the magnon and phonon harmonic (e.g., dispersion, specific heat, and group velocity) and anharmonic (e.g., scattering rate) properties, based on which their thermal conductivity values are calculated. This work represents an example of using SLD simulations to understand the transport properties involving coupled magnon and phonon dynamics.

  4. A molecular-dynamics simulation of displacement cascades in α-iron

    International Nuclear Information System (INIS)

    Kusunoki, Katsuyuki

    2003-01-01

    A molecular-dynamics code has been developed for simulating the early process of radiation-induced defects generation and aggregation during displacement cascades in α-iron. This code reproduces the dynamics of various types of defects such as vacancies, interstitials, and their clusters in a crystal composed of a million atoms. Main procedures and results of the present simulation are as follows. Interactions among atoms were described by a many-body EAM potential. Every simulation was performed under 3D periodical boundary conditions. Cascades were introduced into crystals by giving a kinetic energy to a knock-on atom once at a time toward a crystallographic direction along low index axes i.e. , and axes. The maximum number of Frenkel-type defects was generated for a case when the knock-on direction was along axis. Interstitial atoms surrounding residual vacancies were observed to form several clusters shortly after pair annihilation of the Frenkel-type defects. Fast massive migration of the interstitial clusters was also observed. (author)

  5. Atomistic simulation of the premelting of iron and aluminum : Implications for high-pressure melting-curve measurements

    NARCIS (Netherlands)

    Starikov, Sergey V.; Stegailov, Vladimir V.

    2009-01-01

    Using atomistic simulations we show the importance of the surface premelting phenomenon for the melting-curve measurements at high pressures. The model under consideration mimics the experimental conditions deployed for melting studies with diamond-anvil cells. The iron is considered in this work

  6. EFFECTIVENESS OF USING DILUTE OXALIC ACID TO DISSOLVE HIGH LEVEL WASTE IRON BASED SLUDGE SIMULANT

    International Nuclear Information System (INIS)

    Ketusky, E

    2008-01-01

    At the Savannah River Site (SRS), near Aiken South Carolina, there is a crucial need to remove residual quantities of highly radioactive iron-based sludge from large select underground storage tanks (e.g., 19,000 liters of sludge per tank), in order to support tank closure. The use of oxalic acid is planned to dissolve the residual sludge, hence, helping in the removal. Based on rigorous testing, primarily using 4 and 8 wt% oxalic acid solutions, it was concluded that the more concentrated the acid, the greater the amount of residual sludge that would be dissolved; hence, a baseline technology on using 8 wt% oxalic acid was developed. In stark contrast to the baseline technology, reports from other industries suggest that the dissolution will most effectively occur at 1 wt% oxalic acid (i.e., maintaining the pH near 2). The driver for using less oxalic acid is that less (i.e., moles) would decrease the severity of the downstream impacts (i.e., required oxalate solids removal efforts). To determine the initial feasibility of using 1 wt% acid to dissolve > 90% of the sludge solids, about 19,000 liters of representative sludge was modeled using about 530,000 liters of 0 to 8 wt% oxalic acid solutions. With the chemical thermodynamic equilibrium based software results showing that 1 wt% oxalic acid could theoretically work, simulant dissolution testing was initiated. For the dissolution testing, existing simulant was obtained, and an approximate 20 liter test rig was built. Multiple batch dissolutions of both wet and air-dried simulant were performed. Overall, the testing showed that dilute oxalic acid dissolved a greater fraction of the stimulant and resulted in a significantly larger acid effectiveness (i.e., grams of sludge dissolved/mole of acid) than the baseline technology. With the potential effectiveness confirmed via simulant testing, additional testing, including radioactive sludge testing, is planned

  7. Combining optimisation and simulation in an energy systems analysis of a Swedish iron foundry

    International Nuclear Information System (INIS)

    Mardan, Nawzad; Klahr, Roger

    2012-01-01

    To face global competition, and also reduce environmental and climate impact, industry-wide changes are needed, especially regarding energy use, which is closely related to global warming. Energy efficiency is therefore an essential task for the future as it has a significant impact on both business profits and the environment. For the analysis of possible changes in industrial production processes, and to choose what changes should be made, various modelling tools can be used as a decision support. This paper uses two types of energy analysis tool: Discrete Event Simulation (DES) and Energy Systems Optimisation (ESO). The aim of this study is to describe how a DES and an ESO tool can be combined. A comprehensive five-step approach is proposed for reducing system costs and making a more robust production system. A case study representing a new investment in part of a Swedish iron foundry is also included to illustrate the method's use. The method described in this paper is based on the use of the DES program QUEST and the ESO tool reMIND. The method combination itself is generic, i.e. other similar programs can be used as well with some adjustments and adaptations. The results from the case study show that when different boundary conditions are used the result obtained from the simulation tools is not optimum, in other words, the result shows only a feasible solution and not the best way to run the factory. It is therefore important to use the optimisation tool in such cases in order to obtain the optimum operating strategy. By using the optimisation tool a substantial amount of resources can be saved. The results also show that the combination of optimisation and simulation tools is useful to provide very detailed information about how the system works and to predict system behaviour as well as to minimise the system cost. -- Highlights: ► This study describes how a simulation and an optimisation tool can be combined. ► A case study representing a new

  8. Molecular dynamics simulation of displacement cascades in iron-alpha; Cascades de deplacements atomiques dans le FER-alpha simulation par dynamique moleculaire

    Energy Technology Data Exchange (ETDEWEB)

    Vascon, R

    1997-12-31

    Radiation damage by neutrons or ions in bcc iron has been investigated by molecular dynamics simulations using an embedded atom type many-body potential (EAM). Displacement cascades with energies of 1 to 30 keV were generated in the microcanonical system where the number of atoms (up to 1.5 million) is chosen high enough to compensate the fact that the dissipation of energy is not taken into account in our model. The defect number at the end of cascade lifetime was found to be 60 percent of the NRT standard value. This tendency is in good agreement with experimental data. However, compared with other simulations in iron, we found significant differences in the defect production and distribution. The comparison with results obtained form simulations of cascades in other metals, leads on the one hand to a higher value of the defect number in bcc iron than in fcc metals like copper or nickel, and on the other hand to a ratio, between the number of replacements and the number of defects, lower in iron ( 100). We observed the transient melting of the core of the cascade during simulations. We showed that a higher value of the initial iron crystal temperature, as the mass difference between the components of an artificial binary alloy Fe-X(X=Al,Sb,Au,U) both produce a `cascade effect`: a decrease of the number of defects and an increase of the number of replacements. We also showed up the quasi-channeling of some atoms in high energy cascades. They are at the origin of sub-cascades formation; as a result they induce an opposite effect to the `cascade effect`. (author). 286 refs.

  9. Pyrophosphate synthesis in iron mineral films and membranes simulating prebiotic submarine hydrothermal precipitates

    Science.gov (United States)

    Barge, Laura M.; Doloboff, Ivria J.; Russell, Michael J.; VanderVelde, David; White, Lauren M.; Stucky, Galen D.; Baum, Marc M.; Zeytounian, John; Kidd, Richard; Kanik, Isik

    2014-03-01

    Cells use three main ways of generating energy currency to drive metabolism: (i) conversion of adenosine diphosphate (ADP) to adenosine triphosphate (ATP) by the proton motive force through the rotor-stator ATP synthase; (ii) the synthesis of inorganic phosphate˜phosphate bonds via proton (or sodium) pyrophosphate synthase; or (iii) substrate-level phosphorylation through the direct donation from an active phosphoryl donor. A mechanism to produce a pyrophosphate bond as “energy currency” in prebiotic systems is one of the most important considerations for origin of life research. Baltscheffsky (1996) suggests that inorganic pyrophosphate (PO74-; PPi) may have preceded ATP/ADP as an energy storage molecule in earliest life, produced by an H+ pyrophosphatase. Here we test the hypothesis that PPi could be synthesized in inorganic precipitates simulating hydrothermal chimney structures transected by thermal and/or ionic gradients. Appreciable yields of PPi were obtained via substrate phosphorylation by acetyl phosphate within the iron sulfide/silicate precipitates at temperatures expected for an alkaline hydrothermal system. The formation of PPi only occurred in the solid phase, i.e. when both Pi and the phosphoryl donor were precipitated with Fe-sulfides or Fe-silicates. The amount of Ac-Pi incorporated into the precipitate was a significant factor in the amount of PPi that could form, and phosphate species were more effectively incorporated into the precipitate at higher temperatures (⩾50 to >85 °C). Thus, we expect that the hydrothermal precipitate would be more enriched in phosphate (and especially, Ac-Pi) near the inner margins of a hydrothermal mound where PPi formation would be at a maximum. Iron sulfide and iron silicate precipitates effectively stabilized Ac-Pi and PPi against hydrolysis (relative to hydrolysis in aqueous solution). Thus it is plausible that PPi could accumulate as an energy currency up to useful concentrations for early life in a

  10. Formation of Nanophase Iron in Lunar Soil Simulant for Use in ISRU Studies

    Science.gov (United States)

    Liu, Yang; Taylor, Lawrence A.; Hill, Eddy; Day, James D. M.

    2005-01-01

    For the prospective return of humans to the Moon and the extensive amount of premonitory studies necessary, large quantities of lunar soil simulants are required, for a myriad of purposes from construction/engineering purposes all the way to medical testing of its effects from ingestion by humans. And there is only a limited and precious quantity of lunar soil available on Earth (i.e., Apollo soils) - therefore, the immediate need for lunar soil simulants. Since the Apollo era, there have been several simulants; of these JSC-1 (Johnson Space Center) and MLS-1 (Minnesota Lunar Simulant) have been the most widely used. JSC-1 was produced from glassy volcanic tuff in order to approximate lunar soil geotechnical properties; whereas, MLS-1 approximates the chemistry of Apollo 11 high-Ti soil, 10084. Stocks of both simulants are depleted, but JSC-1 has recently gone back into production. The lunar soil simulant workshop, held at Marshall Space Flight Center in January 2005, identified the need to make new simulants for the special properties of lunar soil, such as nanophase iron (np-Fe(sup 0). Hill et al. (2005, this volume) showed the important role of microscale Fe(sup 0) in microwave processing of the lunar soil simulants JSC-1 and MLS-1. Lunar soil is formed by space weathering of lunar rocks (e.g., micrometeorite impact, cosmic particle bombardment). Glass generated during micrometeorite impact cements rock and mineral fragments together to form aggregates called agglutinates, and also produces vapor that is deposited and coats soil grains. Taylor et al. (2001) showed that the relative amount of impact glass in lunar soil increases with decreasing grain size and is the most abundant component in lunar dust (less than 20 micrometer fraction). Notably, the magnetic susceptibility of lunar soil also increases with the decreasing grain size, as a function of the amount of nanophase-sized Fe(sup 0) in impact-melt generated glass. Keller et al. (1997, 1999) also

  11. Degradation of nitrobenzene in simulated wastewater by iron-carbon micro-electrolysis packing.

    Science.gov (United States)

    Li, Meng; Zou, Donglei; Zou, Haochen; Fan, Dongyan

    2011-12-01

    The reductive degradation of nitrobenzene (NB) by iron-carbon micro-electrolysis packing was investigated. The influence of initial NB concentration, pH value and packing amount on the removal rate of NB were studied. The results showed that the reaction with packing followed the pseudo-first-order reaction. The optimum pH was 3.0 for the degradation of NB in the tested pH ranges of 3-9 and the optimum packing amount was 40 g/200 ml. The flow-through column packed with packing was designed to remove NB from simulated wastewater for approximately 68 days. The removal rate was over 90% within initial periods. It could be seen that after running for 68 days, the packing still had good performance after the long-term column experiment. In addition, the changes of the packing surfaces morphologies and matters before, during and after the column experiment were analysed by scanning electron microscopy in conjunction with energy-dispersion spectroscopy (EDS).

  12. Modelling phosphorus (P), sulfur (S) and iron (Fe) interactions for dynamic simulations of anaerobic digestion processes

    DEFF Research Database (Denmark)

    Flores Alsina, Xavier; Solon, Kimberly; Kazadi Mbamba, Christian

    2016-01-01

    (SSO4) reduction by XSRB and storage of XPHA by XPAO; and, (2) decrease of acetoclastic and hydrogenotrophic methanogenesis due to ZH2S inhibition. Model A3 shows the potential for iron to remove free SIS (and consequently inhibition) and instead promote iron sulfide (XFeS) precipitation. It also...

  13. Impact on the Fe redox cycling of organic ligands released by Synechococcus PCC 7002, under different iron fertilization scenarios. Modeling approach

    Science.gov (United States)

    Samperio-Ramos, Guillermo; González-Dávila, Melchor; Santana-Casiano, J. Magdalena

    2018-06-01

    The kinetics of Fe redox transformations are of crucial importance in determining the bioavailability of iron, due to inorganic Fe(II) and Fe weakly organic complexes being the most easily assimilated species by phytoplankton. The role played by the natural organic ligands excreted by the cyanobacteria Synecococcus PCC 7002 on the iron redox chemistry was studied at different stages of growth, considering changes in the organic exudation of the cyanobacteria, associated with growth under two different scenarios of iron availability. The oxidation/reduction processes of iron were studied at nanomolar levels and under different physicochemical conditions of pH (7.2- 8.2), temperature (5- 35 °C) and salinity (10- 37). The presence of natural organic exudates of Synechococcus affected the redox behavior of iron. A pH-dependent and photo-induced Fe(III) reduction process was detected in the presence of exudates produced under Fe-Low conditions. Photolytic reactions also modified the reactivity of those exudates with respect to Fe(II), increasing its lifetime in seawater. Without light mediated processes, organic ligands excreted under iron deficient conditions intensified the Fe(II) oxidation at pH redox constants between iron and the major ligands present in solution. Two organic type ligands for the exudates of Synechococcus PCC 7002, with different iron-chelation properties were included in the model. The Fe(II) speciation was radically affected when organic ligands were considered. The individual contributions to the overall Fe(II) oxidation rate demonstrated that these organic ligands played a key role in the oxidation process, although their contributions were dependent on the prescribed iron conditions. The study, therefore, suggests that the variability in the composition and nature of organic exudates released, due to iron availability conditions, might determine the redox behaviour of iron in seawater.

  14. Comparing the performance of 11 crop simulation models in predicting yield response to nitrogen fertilization

    Czech Academy of Sciences Publication Activity Database

    Salo, T.; Palosuo, T.; Kersebaum, K. C.; Nendel, C.; Angulo, C.; Ewert, F.; Bindi, M.; Calanca, P.; Klein, T.; Moriondo, M.; Ferrise, R.; Olesen, J. E.; Patil, R. H.; Ruget, F.; Takáč, J.; Hlavinka, Petr; Trnka, Miroslav; Rötter, R. P.

    2016-01-01

    Roč. 154, č. 7 (2016), s. 1218-1240 ISSN 0021-8596 R&D Projects: GA MŠk(CZ) LO1415; GA MZe QJ1310123; GA MŠk(CZ) LD13030 EU Projects: European Commission(XE) 268277; European Commission(XE) 292944 Institutional support: RVO:67179843 Keywords : Northern growing conditions * climate change impacts * spring barley * system simulations * soil properties * winter-wheat * dynamics * growth Subject RIV: GC - Agronomy Impact factor: 1.291, year: 2016

  15. 3D atomistic simulation of fatigue behavior of a ductile crack in bcc iron loaded in mode II

    Czech Academy of Sciences Publication Activity Database

    Uhnáková, Alena; Pokluda, J.; Machová, Anna; Hora, Petr

    2012-01-01

    Roč. 61, AUG 2012 (2012), s. 12-19 ISSN 0927-0256 R&D Projects: GA ČR(CZ) GAP108/10/0698 Institutional research plan: CEZ:AV0Z20760514 Keywords : fatigue * mode II * bcc iron * molecular dynamic simulations Subject RIV: JG - Metallurgy Impact factor: 1.878, year: 2012 http://www.sciencedirect.com/science/article/pii/S0927025612001929

  16. Ab-initio simulations of pressure effects on structural and electronic properties of iron based superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Tomic, Milan

    2013-07-01

    The ab-initio molecular dynamics framework has been the cornerstone of computational solid state physics in the last few decades. Although it is already a mature field it is still rapidly developing to accommodate the growth in solid state research as well as to efficiently utilize the increase in computing power. Starting from the first principles, the ab-initio molecular dynamics provides essential information about structural and electronic properties of matter under various external conditions. In this thesis we use the ab-initio molecular dynamics to study the behavior of BaFe{sub 2}As{sub 2} and CaFe{sub 2}As{sub 2} under the application of external pressure. BaFe{sub 2}As{sub 2} and CaFe{sub 2}As{sub 2} belong to the family of iron based superconductors which are a novel and promising superconducting materials. The application of pressure is one of two key methods by which electronic and structural properties of iron based superconductors can be modified, the other one being doping (or chemical pressure). In particular, it has been noted that pressure conditions have an important effect, but their exact role is not fully understood. To better understand the effect of different pressure conditions we have performed a series of ab-initio simulations of pressure application. In order to apply the pressure with arbitrary stress tensor we have developed a method based on the Fast Inertial Relaxation Engine, whereby the unit cell and the atomic positions are evolved according to the metadynamical equations of motion. We have found that the application of hydrostatic and c axis uniaxial pressure induces a phase transition from the magnetically ordered orthorhombic phase to the non-magnetic collapsed tetragonal phase in both BaFe{sub 2}As{sub 2} and CaFe{sub 2}As{sub 2}. In the case of BaFe{sub 2}As{sub 2}, an intermediate tetragonal non-magnetic tetragonal phase is observed in addition. Application of the uniaxial pressure parallel to the c axis reduces the

  17. Ab-initio simulations of pressure effects on structural and electronic properties of iron based superconductors

    International Nuclear Information System (INIS)

    Tomic, Milan

    2013-01-01

    The ab-initio molecular dynamics framework has been the cornerstone of computational solid state physics in the last few decades. Although it is already a mature field it is still rapidly developing to accommodate the growth in solid state research as well as to efficiently utilize the increase in computing power. Starting from the first principles, the ab-initio molecular dynamics provides essential information about structural and electronic properties of matter under various external conditions. In this thesis we use the ab-initio molecular dynamics to study the behavior of BaFe 2 As 2 and CaFe 2 As 2 under the application of external pressure. BaFe 2 As 2 and CaFe 2 As 2 belong to the family of iron based superconductors which are a novel and promising superconducting materials. The application of pressure is one of two key methods by which electronic and structural properties of iron based superconductors can be modified, the other one being doping (or chemical pressure). In particular, it has been noted that pressure conditions have an important effect, but their exact role is not fully understood. To better understand the effect of different pressure conditions we have performed a series of ab-initio simulations of pressure application. In order to apply the pressure with arbitrary stress tensor we have developed a method based on the Fast Inertial Relaxation Engine, whereby the unit cell and the atomic positions are evolved according to the metadynamical equations of motion. We have found that the application of hydrostatic and c axis uniaxial pressure induces a phase transition from the magnetically ordered orthorhombic phase to the non-magnetic collapsed tetragonal phase in both BaFe 2 As 2 and CaFe 2 As 2 . In the case of BaFe 2 As 2 , an intermediate tetragonal non-magnetic tetragonal phase is observed in addition. Application of the uniaxial pressure parallel to the c axis reduces the critical pressure of the phase transition by an order of magnitude

  18. Analysis and simulation of non-metallic inclusions in spheroidal graphite iron

    International Nuclear Information System (INIS)

    Pustal, B; Schelnberger, B; Bührig-Polaczek, A

    2016-01-01

    Non-metallic inclusions in spheroidal cast iron (SGI) reduce fatigue strength and yield strength. This type of inclusion usually accumulates at grain boundaries. Papers addressing this topic show the overall impact of both the fraction of so-called white (carbides) and black (non-metallic) inclusions on mechanical properties. In the present work we focus on the origin and the formation conditions of black Mg-bearing inclusions, further distinguishing between Si-bearing and non-Si-bearing Mg inclusions. The formation was simulated applying thermodynamic approaches. Moreover, appropriate experiments have been carried out and a large number of particles have been studied applying innovative feature analysis with regard to shape, size, and composition. Magnesium silicates are predicted at elevated oxygen concentrations, whereas at low levels of oxygen sulphides and carbides appear at a late stage of solidification. Experiments with three consecutive flow obstacles show that the amount of magnesium silicates decrease after each of the three obstacles, whereas the fraction of non-Si-bearing inclusions remains approximately constant. The size of inclusions divides in halves over the flow path and the number of particles increases accordingly. We point out that based on feature analysis Mg-O-C bearing inclusion show disadvantageous form factors for which reason this kind of inclusions may be extremely harmful in terms of crack initiation. All results obtained indicate that magnesium silicates are entrapped on mould filling, whereas Mg-(O, C, S, P, N) bearing particles are precipitates at late stages of solidification. Consequently, the only avoidance strategy is setting up optimum retained magnesium content. (paper)

  19. Novel Applications for Oxalate-Phosphate-Amine Metal-Organic-Frameworks (OPA-MOFs): Can an Iron-Based OPA-MOF Be Used as Slow-Release Fertilizer?

    Science.gov (United States)

    Anstoetz, Manuela; Rose, Terry J.; Clark, Malcolm W.; Yee, Lachlan H.; Raymond, Carolyn A.; Vancov, Tony

    2015-01-01

    A porous iron-based oxalate-phosphate-amine metal-organic framework material (OPA-MOF) was investigated as a microbially-induced slow-release nitrogen (N) and phosphorus (P) fertilizer. Seedling growth, grain yields, nutrient uptake of wheat plants, and soil dynamics in incubated soil, were investigated using OPA-MOF vs standard P (triple-superphosphate) and N (urea) fertilizers in an acidic Ferralsol at two application rates (equivalent 120 and 40 kg N ha-1). While urea hydrolysis in the OPA-MOF treatment was rapid, conversion of ammonium to nitrate was significantly inhibited compared to urea treatment. Reduced wheat growth in OPA-MOF treatments was not caused by N-deficiency, but by limited P-bioavailability. Two likely reasons were slow P-mobilisation from the OPA-MOF or rapid P-binding in the acid soil. P-uptake and yield in OPA-MOF treatments were significantly higher than in nil-P controls, but significantly lower than in conventionally-fertilised plants. OPA-MOF showed potential as enhanced efficiency N fertilizer. However, as P-bioavailability was insufficient to meet plant demands, further work should determine if P-availability may be enhanced in alkaline soils, or whether central ions other than Fe, forming the inorganic metal-P framework in the MOF, may act as a more effective P-source in acid soils. PMID:26633174

  20. Damage induced by swift heavy ions in a pure metallic target: iron. Experimental results and numerical simulation

    International Nuclear Information System (INIS)

    Legrand, P.

    1993-01-01

    The damage induced when a high energy deposition occurs in the electronic system of a pure metal (Ag, Co, Fe, Ni, Pd, Pt, Ti, W, Zr) has been investigated using two methods: low temperature swift heavy ion (O, Ar, Kr, Xe, Pb, u) irradiations and computer simulations by molecular dynamics. Irradiations reveal that up to now, it is only in iron, titanium, cobalt and zirconium targets that high levels of energy deposition in electronic excitations lead to a new mechanism of defect creation in addition to the effects of elastic collisions. This mechanism might be the Coulomb explosion: the incident ion creates in its wake a cylinder of highly ionized matter; Coulomb repulsions of short duration in metallic targets could then set a great number of neighbouring atoms into motion and lead to permanent atomic displacements. Using molecular dynamics, we confirm that atomic displacements can indeed occur when neighbouring perturbated atoms receive even a very small amount of kinetic energy (≤ 1 eV). This happens only if the repulsive movements are collective and coherent. Defect creation and annealing of preexisting defects which occur in iron at different energy deposition levels are successfully simulated. An original empirical N-body potential, allowing a realistic description of the bulk properties of the body centered cubic iron, is used. (author). refs., figs., tabs

  1. Photosynthesis and oxidative stress in the restinga plant species Eugenia uniflora L. exposed to simulated acid rain and iron ore dust deposition: Potential use in environmental risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Rust Neves, Natalia; Oliva, Marco Antonio; Cruz Centeno, Danilo da; Costa, Alan Carlos; Ferreira Ribas, Rogerio [Departamento de Biologia Vegetal, Universidade Federal de Vicosa, Av. PH Rolfs, Campus, Vicosa, Minas Gerais, 36570-000 (Brazil); Gusmao Pereira, Eduardo, E-mail: egpereira@gmail.com [Departamento de Biologia Vegetal, Universidade Federal de Vicosa, Av. PH Rolfs, Campus, Vicosa, Minas Gerais, 36570-000 (Brazil)

    2009-06-01

    The Brazilian sandy coastal plain named restinga is frequently subjected to particulate and gaseous emissions from iron ore factories. These gases may come into contact with atmospheric moisture and produce acid rain. The effects of the acid rain on vegetation, combined with iron excess in the soil, can lead to the disappearance of sensitive species and decrease restinga biodiversity. The effects of iron ore dust deposition and simulated acid rain on photosynthesis and on antioxidant enzymes were investigated in Eugenia uniflora, a representative shrub species of the restinga. This study aimed to determine the possible utility of this species in environmental risk assessment. After the application of iron ore dust as iron solid particulate matter (SPM{sub Fe}) and simulated acid rain (pH 3.1), the 18-month old plants displayed brown spots and necrosis, typical symptoms of iron toxicity and injuries caused by acid rain, respectively. The acidity of the rain intensified leaf iron accumulation, which reached phytotoxic levels, mainly in plants exposed to iron ore dust. These plants showed the lowest values for net photosynthesis, stomatal conductance, transpiration, chlorophyll a content and electron transport rate through photosystem II (PSII). Catalase and superoxide dismutase activities were decreased by simulated acid rain. Peroxidase activity and membrane injury increased following exposure to acid rain and simultaneous SPM{sub Fe} application. Eugenia uniflora exhibited impaired photosynthetic and antioxidative metabolism in response to combined iron and acid rain stresses. This species could become a valuable tool in environmental risk assessment in restinga areas near iron ore pelletizing factories. Non-invasive evaluations of visual injuries, photosynthesis and chlorophyll a fluorescence, as well as invasive biochemical analysis could be used as markers.

  2. Photosynthesis and oxidative stress in the restinga plant species Eugenia uniflora L. exposed to simulated acid rain and iron ore dust deposition: Potential use in environmental risk assessment

    International Nuclear Information System (INIS)

    Rust Neves, Natalia; Oliva, Marco Antonio; Cruz Centeno, Danilo da; Costa, Alan Carlos; Ferreira Ribas, Rogerio; Gusmao Pereira, Eduardo

    2009-01-01

    The Brazilian sandy coastal plain named restinga is frequently subjected to particulate and gaseous emissions from iron ore factories. These gases may come into contact with atmospheric moisture and produce acid rain. The effects of the acid rain on vegetation, combined with iron excess in the soil, can lead to the disappearance of sensitive species and decrease restinga biodiversity. The effects of iron ore dust deposition and simulated acid rain on photosynthesis and on antioxidant enzymes were investigated in Eugenia uniflora, a representative shrub species of the restinga. This study aimed to determine the possible utility of this species in environmental risk assessment. After the application of iron ore dust as iron solid particulate matter (SPM Fe ) and simulated acid rain (pH 3.1), the 18-month old plants displayed brown spots and necrosis, typical symptoms of iron toxicity and injuries caused by acid rain, respectively. The acidity of the rain intensified leaf iron accumulation, which reached phytotoxic levels, mainly in plants exposed to iron ore dust. These plants showed the lowest values for net photosynthesis, stomatal conductance, transpiration, chlorophyll a content and electron transport rate through photosystem II (PSII). Catalase and superoxide dismutase activities were decreased by simulated acid rain. Peroxidase activity and membrane injury increased following exposure to acid rain and simultaneous SPM Fe application. Eugenia uniflora exhibited impaired photosynthetic and antioxidative metabolism in response to combined iron and acid rain stresses. This species could become a valuable tool in environmental risk assessment in restinga areas near iron ore pelletizing factories. Non-invasive evaluations of visual injuries, photosynthesis and chlorophyll a fluorescence, as well as invasive biochemical analysis could be used as markers.

  3. Effectiveness of Iron Ethylenediamine-N,N'-bis(hydroxyphenylacetic) Acid (o,o-EDDHA/Fe3+) Formulations with Different Ratios of Meso and d,l-Racemic Isomers as Iron Fertilizers.

    Science.gov (United States)

    Alcañiz, Sara; Jordá, Juana D; Cerdán, Mar

    2017-01-18

    Two o,o-EDDHA/Fe 3+ formulations (meso, 93.5% w/w of meso isomer; and d,l-racemic, 91.3% w/w of d,l-racemic mixture) were prepared, and their efficacy to avoid or to relieve iron deficiency in Fe-sufficient and Fe-deficient tomato plants grown on hydroponic solution was compared with that of the current o,o-EDDHA/Fe 3+ formulations (50% of meso and d,l-racemic isomers). The effectiveness of the three o,o-EDDHA/Fe 3+ formulations was different depending on the iron nutritional status of plants. The three o,o-EDDHA/Fe 3+ formulations tested were effective in preventing iron chlorosis in healthy plants. However, the higher the meso concentration in the formulations, the higher the effectiveness in the recovery of iron chlorotic plants from iron deficiency. Accordingly, o,o-EDDHA/Fe 3+ formulations rich in meso isomer are recommended in hydroponic systems.

  4. Effectiveness of Iron Ethylenediamine-N,N′-bis(hydroxyphenylacetic) Acid (o,o-EDDHA/Fe3+) Formulations with Different Ratios of Meso and d,l-Racemic Isomers as Iron Fertilizers

    OpenAIRE

    Alcañiz Lucas, Sara; Jordá Guijarro, Juana Dolores; Cerdán, Mar

    2017-01-01

    Two o,o-EDDHA/Fe3+ formulations (meso, 93.5% w/w of meso isomer; and d,l-racemic, 91.3% w/w of d,l-racemic mixture) were prepared, and their efficacy to avoid or to relieve iron deficiency in Fe-sufficient and Fe-deficient tomato plants grown on hydroponic solution was compared with that of the current o,o-EDDHA/Fe3+ formulations (50% of meso and d,l-racemic isomers). The effectiveness of the three o,o-EDDHA/Fe3+ formulations was different depending on the iron nutritional status of plants. T...

  5. First-Principles and Thermodynamic Simulation of Elastic Stress Effect on Energy of Hydrogen Dissolution in Alpha Iron

    Science.gov (United States)

    Rakitin, M. S.; Mirzoev, A. A.; Mirzaev, D. A.

    2018-04-01

    Mobile hydrogen, when dissolving in metals, redistributes due to the density gradients and elastic stresses, and enables destruction processes or phase transformations in local volumes of a solvent metal. It is rather important in solid state physics to investigate these interactions. The first-principle calculations performed in terms of the density functional theory, are used for thermodynamic simulation of the elastic stress effect on the energy of hydrogen dissolution in α-Fe crystal lattice. The paper presents investigations of the total energy of Fe-H system depending on the lattice parameter. As a result, the relation is obtained between the hydrogen dissolution energy and stress. A good agreement is shown between the existing data and simulation results. The extended equation is suggested for the chemical potential of hydrogen atom in iron within the local stress field. Two parameters affecting the hydrogen distribution are compared, namely local stress and phase transformations.

  6. Atomic-scale simulation study of some bulk and interfacial properties of iron aluminium ordered alloys

    International Nuclear Information System (INIS)

    Besson, Remy

    1997-01-01

    A semi-empirical potential was designed for B 2 and DO 3 iron aluminides and used to study point defects and grain boundaries in these compounds. At low temperature, departure from B 2 stoichiometry is accommodated with antisite defects; when T increases, iron vacancies appear and defects have a trend to form clusters, the structure of which is very sensitive to this departure. Our calculations, relying on T = 0 K formation energies, predict the nature of major defects, but lead to underestimated quantitative results, which may point out the essential role of atomic vibrations. In the stoichiometric B 2 compound, the diffusion of both species is induced by four-jump cycles involving iron vacancies. Although the agreement between our calculated activation energies and other experiments is good, the calculated diffusion coefficients are below the experimental ones. Here again, this discrepancy may be put down to the overlooking of phonon contributions. The second application concerns the atomic structures of the [001] (310) symmetric tilt grain boundary in the B 2 and DO 3 compounds. At low temperature, in the stoichiometric B 2 compound, we obtain an iron-rich single stable structure (pseudo-symmetric), whose structure is strongly influenced by the bulk composition (with intergranular segregation of the major element). In the stoichiometric DO 3 compound, many energetically equivalent structures exist, all being systematically aluminium-rich. The study of the B 2 grain boundary structure at high temperature shows a phase transition favouring a symmetric structure. Its high excess energy at low temperature emphasizes the influence of atomic vibrations in the interfacial properties of B 2 Fe-Al compounds. (author) [fr

  7. 3D atomistic simulation of fatigue behavior of a ductile crack in bcc iron

    Czech Academy of Sciences Publication Activity Database

    Uhnáková, Alena; Machová, Anna; Hora, Petr

    2011-01-01

    Roč. 33, č. 9 (2011), s. 1182-1188 ISSN 0142-1123 R&D Projects: GA ČR(CZ) GAP108/10/0698 Institutional research plan: CEZ:AV0Z20760514 Keywords : 3D molecular dynamics * fatigue * bcc iron * mode I Subject RIV: JG - Metallurgy Impact factor: 1.546, year: 2011 http://www.sciencedirect.com/science/article/pii/S0142112311000600

  8. Crack-induced stress, dislocations and acoustic emission by 3-D atomistic simulation in bcc iron

    Czech Academy of Sciences Publication Activity Database

    Spielmannová, Alena; Machová, Anna; Hora, Petr

    2009-01-01

    Roč. 57, č. 14 (2009), s. 4065-4073 ISSN 1359-6454 R&D Projects: GA ČR GA101/09/1630; GA AV ČR KJB200760802; GA ČR(CZ) GA101/07/0789 Institutional research plan: CEZ:AV0Z20760514 Keywords : bcc iron * crack * dislocation emisision Subject RIV: JG - Metallurgy Impact factor: 3.760, year: 2009

  9. Computer simulation of interstitial atom loop with vacancies in gamma-iron lattice

    International Nuclear Information System (INIS)

    Golubov, S.I.; Doronina, V.I.; Kaipetskaya, E.N.

    1985-01-01

    The interaction of vacanies and a dislocation loop has been investigated by the mashine stimulation method. The calculations have been performed by the variation method using the Jonson pair potential for gamma-iron. The interaction of a vacancy and a loop of interstitial atoms in the form of a regular hexagon has been investigated. The results obtained are compared with calculations in the elastic approximation

  10. Nano Fertilizers

    Directory of Open Access Journals (Sweden)

    Hatice DAĞHAN

    2017-06-01

    Full Text Available Agricultural land is decreasing day by day due to erosion, environmental pollution, unconscious irrigation and fertilization. On the other hand, it is necessary to increase agricultural production in order to meet the needs of the developing industry as well as the nutritional needs of the growing population. In the recent years, nano fertilizers have begun to be produced to obtain the highest amount and quality of production from the unit area. Previous research shows that nano fertilizers cause an increase in the use efficiency of plant nutrients, reduce soil toxicity, minimize the potential adverse effects of excessive chemical fertilizer use, and reduce fertilizer application frequency. Nano fertilizers are important in agriculture to increase crop yield and nutrient use efficiency, and to reduce excessive use ofchemical fertilizers. The most important properties of these fertilizers are that they contain one or more of macro and micronutrients, they can be applied frequently in small amounts and are environmentally friendly. However, when applied at high doses, they exhibit decreasing effects on plant growth and crop yields, similar to chemical fertilizers. In this review, the definition, importan ce, and classification of nano fertilizers, their application in plant production, advantages and disadvantages and the results obtained in this field were discussed.

  11. Electron-capture and Low-mass Iron-core-collapse Supernovae: New Neutrino-radiation-hydrodynamics Simulations

    Science.gov (United States)

    Radice, David; Burrows, Adam; Vartanyan, David; Skinner, M. Aaron; Dolence, Joshua C.

    2017-11-01

    We present new 1D (spherical) and 2D (axisymmetric) simulations of electron-capture (EC) and low-mass iron-core-collapse supernovae (SN). We consider six progenitor models: the ECSN progenitor from Nomoto; two ECSN-like low-mass low-metallicity iron-core progenitors from A. Heger (2016, private communication); and the 9, 10, and 11 {M}⊙ (zero-age main-sequence) progenitors from Sukhbold et al. We confirm that the ECSN and ESCN-like progenitors explode easily even in 1D with explosion energies of up to a 0.15 Bethes (1 {{B}}\\equiv {10}51 {erg}), and are a viable mechanism for the production of very-low-mass neutron stars. However, the 9, 10, and 11 {M}⊙ progenitors do not explode in 1D and are not even necessarily easier to explode than higher-mass progenitor stars in 2D. We study the effect of perturbations and of changes to the microphysics and we find that relatively small changes can result in qualitatively different outcomes, even in 1D, for models sufficiently close to the explosion threshold. Finally, we revisit the impact of convection below the protoneutron star (PNS) surface. We analyze 1D and 2D evolutions of PNSs subject to the same boundary conditions. We find that the impact of PNS convection has been underestimated in previous studies and could result in an increase of the neutrino luminosity by up to factors of two.

  12. A computer simulation of iron corrosion in a sodium loop using the Fleitman-Isaacs' solubility relationship

    International Nuclear Information System (INIS)

    Polley, M.V.; Skyrme, G.

    1975-11-01

    At the present time, no theoretical treatment of mass transfer in sodium loops has been able to reconcile the low observed corrosion rates with values of iron solubility recommended in the literature. Although measured values of the solubility of iron in sodium have varied very widely, one recent determination by Fleitman and Isaacs gave low values at low oxygen activities. These values were used in the present work for predicting, by conventional mass transfer theory, corrosion in a non-isothermal loop. The method was to simulate mass transfer using a computer program while following the sodium around the loop until equilibrium was established. The advantages of this method are that the concentration driving force is predicted for all parts of the loop and that changes in mass transfer rates with change in temperature distribution and geometry can be easily investigated. The predicted variation of corrosion rate in the hot isothermal region is reported as a function of sodium velocity, downstream position, temperature, temperature differential, oxygen concentration and loop geometry. Both surface controlled and diffusion controlled mass transfer were investigated and the results were compared with the data of Thorley and Tyzack reported in the literature. (author)

  13. Casting and stress-strain simulations of a cast ductile iron component using microstructure based mechanical behavior

    International Nuclear Information System (INIS)

    Olofsson, Jakob; Svensson, Ingvar L

    2012-01-01

    The industrial demand for increased component performance with concurrent reductions in component weight, development times and verifications using physical prototypes drives the need to use the full potential of casting and Finite Element Method (FEM) simulations to correctly predict the mechanical behavior of cast components in service. The mechanical behavior of the component is determined by the casting process, and factors as component geometry and casting process parameters are known to affect solidification and microstructure formation throughout the component and cause local variations in mechanical behavior as well as residual stresses. Though residual stresses are known to be an important factor in the mechanical behavior of the component, the importance of local mechanical behavior is not well established and the material is typically considered homogeneous throughout the component. This paper deals with the influence of solidification and solid state transformation on microstructure formation and the effect of local microstructure variations on the mechanical behavior of the cast component in service. The current work aims to investigate the coupling between simulation of solidification, microstructure and local variations in mechanical behavior and stress-strain simulation. This is done by performing several simulations of a ductile iron component using a recently developed simulation strategy, a closed chain of simulations for cast components, able to predict and describe the local variations in not only elastic but also plastic behavior throughout the component by using microstructural parameters determined by simulations of microstructural evolution in the component during the casting process. In addition the residual stresses are considered. The results show that the FEM simulation results are significantly affected by including microstructure based mechanical behavior. When the applied load is low and the component is subjected to stress levels

  14. Effects of simulated deposition of acid mist and iron ore particulate matter on photosynthesis and the generation of oxidative stress in Schinus terebinthifolius Radii and Sophora tomentosa L

    Energy Technology Data Exchange (ETDEWEB)

    Kuki, Kacilda Naomi [Departamento de Biologia Vegetal, Universidade Federal de Vicosa (Brazil)], E-mail: naomikuki@hotmail.com; Oliva, Marco Antonio; Pereira, Eduardo Gusmao; Costa, Alan Carlos [Departamento de Biologia Vegetal, Universidade Federal de Vicosa (Brazil); Cambraia, Jose [Departamento de Biologia Geral, Universidade Federal de Vicosa (Brazil)

    2008-09-15

    Particulate matter is a natural occurrence in the environment, but some industries, such as the iron ore sector, can raise the total amount of particles in the atmosphere. This industry is primarily a source of iron and sulfur dioxide particulates. The effects of the pollutants from the iron ore industries on representatives of restinga vegetation in a Brazilian coastal ecosystem were investigated using physiological and biochemical measures. Two species, Schinus terebinthifolius and Sophora tomentosa, were exposed to simulated deposition of acid mist and iron ore particulate matter in acrylic chambers in a greenhouse. Parameters such as gas exchange, fluorescence emission, chlorophyll content, total iron content, antioxidant enzyme activity and malondialdehyde content were assessed in order to evaluate the responses of the two species. Neither treatment was capable of inducing oxidative stress in S. terebinthifolius. Nevertheless, the deposition of iron ore particulates on this species increased chlorophyll content, the maximum quantum efficiency of photosystem II and the electron transport rate, while iron content was unaltered. On the other hand, S. tomentosa showed a greater sensitivity to the treatments. Plants of S. tomentosa that were exposed to acid mist had a decrease in photosynthesis, while the deposition of iron particulate matter led to an increase in iron content and membrane permeability of the leaves. The activities of antioxidant enzymes, such as catalases and superoxide dismutase, were enhanced by both treatments. The results suggested that the two restinga species use different strategies to overcome the stressful conditions created by the deposition of particulate matter, either solid or wet. It seems that while S. terebinthifolius avoided stress, S. tomentosa used antioxidant enzyme systems to partially neutralize oxidative stress. The findings also point to the potential use of S. tomentosa as a biomarker species under field conditions.

  15. Effects of simulated deposition of acid mist and iron ore particulate matter on photosynthesis and the generation of oxidative stress in Schinus terebinthifolius Radii and Sophora tomentosa L.

    Science.gov (United States)

    Kuki, Kacilda Naomi; Oliva, Marco Antônio; Pereira, Eduardo Gusmão; Costa, Alan Carlos; Cambraia, José

    2008-09-15

    Particulate matter is a natural occurrence in the environment, but some industries, such as the iron ore sector, can raise the total amount of particles in the atmosphere. This industry is primarily a source of iron and sulfur dioxide particulates. The effects of the pollutants from the iron ore industries on representatives of restinga vegetation in a Brazilian coastal ecosystem were investigated using physiological and biochemical measures. Two species, Schinus terebinthifolius and Sophora tomentosa, were exposed to simulated deposition of acid mist and iron ore particulate matter in acrylic chambers in a greenhouse. Parameters such as gas exchange, fluorescence emission, chlorophyll content, total iron content, antioxidant enzyme activity and malondialdehyde content were assessed in order to evaluate the responses of the two species. Neither treatment was capable of inducing oxidative stress in S. terebinthifolius. Nevertheless, the deposition of iron ore particulates on this species increased chlorophyll content, the maximum quantum efficiency of photosystem II and the electron transport rate, while iron content was unaltered. On the other hand, S. tomentosa showed a greater sensitivity to the treatments. Plants of S. tomentosa that were exposed to acid mist had a decrease in photosynthesis, while the deposition of iron particulate matter led to an increase in iron content and membrane permeability of the leaves. The activities of antioxidant enzymes, such as catalases and superoxide dismutase, were enhanced by both treatments. The results suggested that the two restinga species use different strategies to overcome the stressful conditions created by the deposition of particulate matter, either solid or wet. It seems that while S. terebinthifolius avoided stress, S. tomentosa used antioxidant enzyme systems to partially neutralize oxidative stress. The findings also point to the potential use of S. tomentosa as a biomarker species under field conditions.

  16. Effects of simulated deposition of acid mist and iron ore particulate matter on photosynthesis and the generation of oxidative stress in Schinus terebinthifolius Radii and Sophora tomentosa L

    International Nuclear Information System (INIS)

    Kuki, Kacilda Naomi; Oliva, Marco Antonio; Pereira, Eduardo Gusmao; Costa, Alan Carlos; Cambraia, Jose

    2008-01-01

    Particulate matter is a natural occurrence in the environment, but some industries, such as the iron ore sector, can raise the total amount of particles in the atmosphere. This industry is primarily a source of iron and sulfur dioxide particulates. The effects of the pollutants from the iron ore industries on representatives of restinga vegetation in a Brazilian coastal ecosystem were investigated using physiological and biochemical measures. Two species, Schinus terebinthifolius and Sophora tomentosa, were exposed to simulated deposition of acid mist and iron ore particulate matter in acrylic chambers in a greenhouse. Parameters such as gas exchange, fluorescence emission, chlorophyll content, total iron content, antioxidant enzyme activity and malondialdehyde content were assessed in order to evaluate the responses of the two species. Neither treatment was capable of inducing oxidative stress in S. terebinthifolius. Nevertheless, the deposition of iron ore particulates on this species increased chlorophyll content, the maximum quantum efficiency of photosystem II and the electron transport rate, while iron content was unaltered. On the other hand, S. tomentosa showed a greater sensitivity to the treatments. Plants of S. tomentosa that were exposed to acid mist had a decrease in photosynthesis, while the deposition of iron particulate matter led to an increase in iron content and membrane permeability of the leaves. The activities of antioxidant enzymes, such as catalases and superoxide dismutase, were enhanced by both treatments. The results suggested that the two restinga species use different strategies to overcome the stressful conditions created by the deposition of particulate matter, either solid or wet. It seems that while S. terebinthifolius avoided stress, S. tomentosa used antioxidant enzyme systems to partially neutralize oxidative stress. The findings also point to the potential use of S. tomentosa as a biomarker species under field conditions

  17. Analysis and simulation of the SLD WIC [Warm Iron Calorimeter] PADS hybrid preamplifier circuitry

    International Nuclear Information System (INIS)

    Fox, J.D.; Horelick, D.

    1990-10-01

    The SLD PADS electronics consist of over 9000 channels of charge-sensitive preamplifiers followed by integrated sample/hold data storage, digitizing, and readout circuitry. This paper uses computer simulation techniques to analyze critical performance parameters of the preamplifier hybrid including its interactions with the detector system. Simulation results are presented and verified with measured performance. 6 refs., 9 figs

  18. Zero-valent iron for the removal of soluble uranium in simulated DOE site groundwater

    International Nuclear Information System (INIS)

    Bostick, W.D.; Jarabek, R.J.; Fiedor, J.N.

    1997-01-01

    Groundwater at the Bear Creek Valley Characterization Area, located at the Oak Ridge Y-12 Plant, is contaminated with regulated metals and volatile organic compounds (VOCs) due to former site activities and disposal practices. The contaminant of principle concern, from the perspective of protecting human health, is soluble uranium, which is present in some waters at concentrations up to a few parts-per-million. We present product speciation and relative reaction kinetics; for removal of soluble uranium under oxic and anoxic conditions with use of zero-valent iron. Under oxic conditions, U(VI) is rapidly and strongly sorbed to hydrous ferric oxide particulate (open-quotes rustclose quotes), whereas uranium is slowly and incompletely reduced to U(IV) under anoxic conditions

  19. Resistivity recovery simulations of electron-irradiated iron: Kinetic Monte Carlo versus cluster dynamics

    International Nuclear Information System (INIS)

    Dalla Torre, J.; Fu, C.-C.; Willaime, F.; Barbu, A.; Bocquet, J.-L.

    2006-01-01

    The isochronal resistivity recovery in high purity α-iron irradiated by electrons was successfully reproduced by a multiscale modelling approach. The stability and mobility of small self-defect clusters determined by ab initio methods were used as input data for an event based Kinetic Monte Carlo (KMC) model, used to explore the defect population evolution during the annealing and to extract the resistivity recovery peaks. In this paper, we investigate the possibility of using an efficient mesoscale model, the Cluster Dynamics (CD), instead of KMC in this approach. The comparison between the two methods for various CD initial conditions shows the importance of spatial correlations between defects, which are neglected in the CD model. However, using appropriate initial conditions, e.g. starting from the concentration of Frenkel pairs after the uncorrelated stage I E , the CD model captures the main characteristics of subsequent defect population evolution, and it can therefore be used for fast and semi-quantitative investigations

  20. First-principles simulations of iron with nitrogen: from surface adsorption to bulk diffusion

    International Nuclear Information System (INIS)

    Wu, M H; Liu, X H; Gu, J F; Jin, Z H

    2013-01-01

    Adsorption, absorption and diffusion pathways of nitrogen are studied for ferromagnetic body-centered cubic iron via spin-polarized density functional theory in combination with the climbing image nudged elastic band method. The computed data suggest that, depending on the coverage of N atoms, N prefers to stay on particular surface sites. Once pinned down well below the surface, N prefers to move into octahedral interstices rather than tetrahedral interstices. However, the tetrahedral interstices are crucial because they act as transition states and yield the saddle point energies of the corresponding minimum energy pathways. In comparison with carbon, we found that nitrogen prefers a different pathway from the (1 0 0) surface to the subsurface due to its strong repulsive interaction with Fe ions. (paper)

  1. Integrating Mobile Phones into Science Teaching to Help Students Develop a Procedure to Evaluate the Corrosion Rate of Iron in Simulated Seawater

    Science.gov (United States)

    Moraes, Edgar P.; Confessor, Mario R.; Gasparotto, Luiz H. S.

    2015-01-01

    This article proposes an indirect method to evaluate the corrosion rate of iron nail in simulated seawater. The official procedure is based on the direct measurement of the specimen's weight loss over time; however, a highly precise scale is required and such equipment may not be easily available. On the other hand, mobile phones equipped with…

  2. Monte Carlo simulation for the estimation of iron in human whole ...

    Indian Academy of Sciences (India)

    2017-02-10

    Feb 10, 2017 ... Monte Carlo N-particle (MCNP) code has been used to simulate the transport of gamma photon rays ... experimental data, and better than the theoretical XCOM values. ... tions in the materials, according to probability density.

  3. USE OF THE “ROTHC” MODEL TO SIMULATE SOIL ORGANIC CARBON DYNAMICS ON A SILTY-LOAM INCEPTISOL IN NORTHERN ITALY UNDER DIFFERENT FERTILIZATION PRACTICES

    Directory of Open Access Journals (Sweden)

    Rosa Francaviglia

    2014-01-01

    Full Text Available We evaluated the efficiency of the RothC model to simulate Soil Organic Carbon (SOC dynamics after 12 years of organic and mineral fertilization practices in a study area located in northern Italy, on a silty-loam Inceptisol with a rotation including tomato, maize and alfalfa. The model performance was assessed by RMSE and EF coefficients. RothC simulated well observed SOC decreases in 71 samples (RMSE=7.42; EF=0.79, while performed with less accuracy when considering all samples (96 samples; RMSE=12.37; EF=0.58, due to the fact that the model failed in case of measured SOC increases (25 samples; RMSE=20.77; EF=-0.038. The model was used to forecast the SOC dynamics over a 50 year period under the same pedoclimatic conditions. Only clay contents >15% allowed to predict increasing levels of SOC respect to the starting values.

  4. Carbon sequestration by patch fertilization: A comprehensive assessment using coupled physical-ecological-biogeochemical models

    Energy Technology Data Exchange (ETDEWEB)

    Sarmiento, Jorge L. [Princeton Univ., NJ (United States); Gnanadesikan, Anand [Princeton Univ., NJ (United States); Gruber, Nicolas [Univ. of California, Los Angeles, CA (United States); Jin, Xin [Univ. of California, Los Angeles, CA (United States); Armstrong, Robert [State Univ. of New York (SUNY), Plattsburgh, NY (United States)

    2007-06-21

    first three years of our project, led to several major new insights on the interaction between ocean biogeochemistry and circulation. This work, which is described in the following Section II on “Large scale fertilization,” has continued to appear in the literature over the past few years, including two high visibility papers in Nature. Early on in the first three years of our project, it became clear that small "patch-scale" fertilizations over limited regions of order 100 km diameter were much more likely than large scale fertilization, and we carried out a series of idealized patch fertilization simulations reported on in Gnanadesikan et al. (2003). Based on this paper and other results we had obtained by the end of our first three-year grant, we identified a number of important issues that needed to be addressed in the second three-year period of this grant. Section III on “patch fertilization” discusses the major findings of this phase of our research, which is described in two major manuscripts that will be submitted for publication in the near future. This research makes use of new more realistic ocean ecosystem and iron cycling models than our first paper on this topic. We have several major new insights into what controls the efficiency of iron fertilization in the ocean. Section IV on “model development” summarizes a set of papers describing the progress that we made on improving the ecosystem models we use for our iron fertilization simulations.

  5. Dissolved greenhouse gases (nitrous oxide and methane) associated with the natural iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean

    Science.gov (United States)

    Farías, L.; Florez-Leiva, L.; Besoain, V.; Fernández, C.

    2014-08-01

    The concentrations of greenhouse gases (GHGs) like nitrous oxide (N2O) and methane (CH4) were measured in the Kerguelen Plateau Region (KPR), an area with annual microalgal bloom caused by natural Fe fertilization, which may stimulate microbes involved in GHG cycling. This study was carried out during the KEOPS 2 cruise during the austral spring of 2011. Two transects were sampled along and across the KRP, the north-south (N-S) transect (46-51° S, 72° E meridian) and the west-east (W-E) transect (66-75° E, 48.3° S latitude), both associated with the presence of a plateau, polar fronts and other mesoscale features. The W-E transect had N2O levels ranging from equilibrium (105%) to light supersaturation (120%) with respect to the atmosphere. CH4 levels fluctuated dramatically, with intense supersaturations (120-970%) in areas close to the coastal waters of Kerguelen Island and in the polar front (PF). There, Fe and nutrient fertilization seem to promote high total chlorophyll a (TChl a) levels. The distribution of both gases was more homogenous in the N-S transect, but CH4 peaked at southeastern stations of the KPR (A3 stations), where phytoplankton bloom was observed. Both gases responded significantly to the patchy distribution of particulate matter as Chl a, stimulated by Fe supply by complex mesoscale circulation. While CH4 appears to be produced mainly at the pycnoclines, N2O seems to be consumed superficially. Air-sea fluxes for N2O (from -10.5 to 8.65, mean 1.71 μmol m-2d-1), and for CH4 (from 0.32 to 38.1, mean 10.07 μmol m-2d-1) reflected sink and source behavior for N2O and source behavior for CH4, with considerable variability associated with a highly fluctuating wind regime and, in the case of CH4, due to its high superficial levels that had not been reported before in the Southern Ocean and may be caused by an intense microbial CH4 cycling.

  6. Fertility desires and fertility outcomes.

    Science.gov (United States)

    Bracher, M; Santow, G

    1991-05-01

    An Australian 1-in-1000 national probability sample conducted in 1986 yielded 2547 women aged 20-59 who provided detailed life histories on marital unions, childbearing, and contraception. Age specific fertility rates, desired family size, differentials in desired family size, desired fertility and achieved fertility, and sequential family building are examined. The results indicate that the desired family size at 1st marriage has declined only slightly over the past 30 years. 3 children are generally desired, and ver few desire 2. The constance of fertility desires in contrasted with the fertilitydecline to below replacement levels. Several reasons are suggested for the desired family size: the desire is for a family size within the family tradition and modified by the desire to have 1 of each sex, the desire reflects less on intentions but more on normative pressure to become a parent. Marrying is self selecting on the desire for a traditional family of at least 2 children. There is a rising age at marriage as well as a decline in marriages. Desired family size exceeds completed fertility. Period factors and personal circumstances affect fertility intentions. Future inquires should explore the multiple factors relating to fertility, rather than in comparing fertility desires and actual fertility. The data collected on age specific fertility were comparable to official estimates. The fertility decline was evidenced in all groups except teenagers. The decline was nearly 50% for those 20-24 years between the 1050's-80's, 33% for ages 25-29. Marriage patterns explain this decline in part. Between 1971-76, women aged 20-25 were married 37 months out of 60 months in 1971-76 versus 25 out of 60 months in 1981-86. Within the 25 year age group, marital fertility has declined and unmarried fertility, which is low, has risen, Women in a marital union of any kind has remained stable. Fertility within de facto unions, which is lower than within marriage, is higher than

  7. Atomistic simulation studies of iron sulphide, platinum antimonide and platinum arsenide

    CSIR Research Space (South Africa)

    Ngoepe, PE

    2005-09-01

    Full Text Available The authors present the results of atomistic simulations using derived interatomic potentials for the pyrite-structured metal chalcogenides FeS2, PtSb2 and PtAs2. Structural and elastic constants were calculated and compared with experimental...

  8. Energy-efficient technology in the iron and steel industry: Simulation of new technology adoption with items

    International Nuclear Information System (INIS)

    Roop, J.M.

    1997-01-01

    The Industrial Technology and Energy Modeling System (ITEMS)(referred to as ISTUM in Jaccard and Roop, 1990) is an end-use industrial modeling system that is technology based. Because it includes technologies in the process description of industry, it is possible to introduce new technologies to determine, based on economic and performance data, how rapidly these new technologies will penetrate the market (Hyman and Roop, 1996). As these new technologies penetrate the market, energy savings and, possibly, emissions reductions occur that can be tracked with the model as well. This report documents the use of ITEMS to investigate the impact of three new technologies under development with funding from the Department of Energy's Office of Industrial Technologies (OIT), that apply to the iron and steel industry. While the results of this application are interesting, this exercise points out how important it is to understand how the technologies work and how they make a difference. This report shows that ITEMS can be a useful tool in estimating market penetration of new technologies and the resulting energy savings, but these results are only as reliable as the data. If the model is to be used to compare technologies, the technical data concerning these technologies must be collected using the same set of assumptions and with the same vision of what characterizes a technology. While an effort has been made to understand how these technologies work, there is no assurance that the data used for this analysis were, indeed, collected using the same vision and the same set of assumptions. The report is organized into five additional sections. The next provides a brief overview of ITEMS and describes how the technical information about OIT projects is used in the model. The third section describes the three technologies that were introduced into ITEMS and reports the relevant data for those projects. The fourth section describes the iron and steel industry, as characterized

  9. Structural Simulation of MHC-peptide Interactions using T-cell Epitope in Iron-acquisition Protein of N. meningitides for Vaccine Design

    Directory of Open Access Journals (Sweden)

    Namrata Mishra

    2010-12-01

    Full Text Available The present work uses a structural simulation approach to identify the potential target vaccine candidates or T cell epitopes (antigenic region that can activate T cell response in two iron acquisition proteins from Neisseria. An iron regulated outer membrane protein frpB: extracellular, [NMB1988], and a Major ferric Iron-binding protein fbpA: periplasmic, [NMB0634] critical for the survival of the pathogen in the host were used. Ten novel promiscuous epitopes from the two iron acquisition proteins were identified using bioinformatics interface. Of these epitopes, 630VQKAVGSIL638 present on frpB with high binding affinity for allele HLA*DR1 was identified with an anchor position at P2, an aliphatic residue at P4 and glycine at P6 making it thereby a potential quality choice for linking peptide-loaded MHC dynamics to T-cell activation and vaccine constructs. The feasibility and structural binding of predicted peptide to the respective HLA allele was investigated by molecular modeling and template-based structural simulation. The conformational properties of the linear peptide were investigated by molecular dynamics using GROMOS96 package and Swiss PDB viewer.

  10. Atomic level simulations of interaction between edge dislocations and irradiation induced ellipsoidal voids in alpha-iron

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Bida [Department of Mechanics, Huazhong University of Science and Technology, Wuhan 430074 (China); Huang, Minsheng, E-mail: mshuang@hust.edu.cn [Department of Mechanics, Huazhong University of Science and Technology, Wuhan 430074 (China); Hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment, Luoyu Road 1037, Wuhan 430074 (China); Li, Zhenhuan [Department of Mechanics, Huazhong University of Science and Technology, Wuhan 430074 (China); Hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment, Luoyu Road 1037, Wuhan 430074 (China)

    2017-04-15

    High concentrations of vacancies tend to be formed inside the metal materials under irradiation, and then accumulate and cluster together gradually to promote the formation of nanovoids. Generally, these voids act as obstacles for dislocation glide and thereby change/degrade the mechanical behavior of irradiated materials. In this work, the interaction between ellipsoidal nanovoids with edge dislocations in alpha-iron has been studied by atomic simulations. The results illuminate that the ellipsoidal void’s semi-major axis on the slip plane and parallel to the dislocation line is the dominant factor controlling the obstacle strength of ellipsoidal nanovoids. Two other semi-major axes, which are perpendicular to the glide plane and parallel to the Burgers vector, respectively, can also influence the critical resolved shear stress (CRSS) for dislocation shearing the ellipsoidal void. The intrinsic atomic mechanisms controlling above phenomena, such as nanovoid-geometry spatial constraint and nanovoid-surface curvature on dislocation evolution, have been discussed carefully. The classical continuum model has been amended to describe the dislocation-ellipsoidal nanovoid interaction base on current results. In addition, the influence of temperature on the CRSS of ellipsoidal nanovoids has also been investigated.

  11. Experimental and simulation studies of iron oxides for geochemical fixation of CO2-SO2 gas mixtures

    Science.gov (United States)

    Garcia, Susana; Rosenbauer, Robert J.; Palandri, James; Maroto-Valer, M. Mercedes

    2011-01-01

    Iron-bearing minerals are reactive phases of the subsurface environment and could potentially trap CO2–SO2gas mixtures derived from fossil fuel combustion processes by their conversion to siderite (FeCO3) and dissolved sulfate. Changes in fluid and mineral compositions resulting from reactions, involving the co-injection of SO2 with CO2 were observed both theoretically and experimentally. Experiments were conducted with a natural hematite (α-Fe2O3) sample. A high pressure-high temperature apparatus was used to simulate conditions in geologic formations deeper than 800 m, where CO2 is in the supercritical state. Solid samples were allowed to react with a NaCl–NaOH brine and SO2-bearing CO2-dominated gas mixtures. The predicted equilibrium mineral assemblage at 100 °C and 250 bar became hematite, dawsonite (NaAl(OH)2CO3), siderite (FeCO3) and quartz (SiO2). Experimentally, siderite and dawsonite, derived from the presence of kaolinite (Al2Si2O5(OH)4) in the parent material, were present in residual solids at longer reaction time intervals, which agreed well with results from the modelling work.

  12. Utilization of struvite recovered from high-strength ammonium-containing simulated wastewater as slow-release fertilizer and fire-retardant barrier.

    Science.gov (United States)

    Yetilmezsoy, Kaan; Kocak, Emel; Akbin, Havva Melda; Özçimen, Didem

    2018-06-28

    Sustainable uses of the struvite (magnesium ammonium phosphate hexahydrate, MgNH 4 PO 4 ·6H 2 O, MAP) recovered from the synthetic wastewater, as a high-quality slow-release fertilizer for the growth of nine medicinal plants and a fire-retardant barrier on the flammability of cotton fabric and wooden plate, were explored in this study. The previous experimental results demonstrated that under the optimal conditions, about 98.7% of [Formula: see text] (initial [Formula: see text] = 1000 mg/L) could be effectively and successfully recovered from simulated wastewater in the form of MAP precipitate. Rates of increase in total fresh weights, total dry weights, and fresh heights of plants grown in soil fertilized with the struvite were determined as 67%, 52%, and 12% for valerian; 121%, 75%, and 18% for cucumber; 421%, 260%, and 47% for dill; 314%, 318%, and 27% for coriander; 432%, 566%, and 30% for tomato; 285%, 683%, and 26% for parsley; 200%, 225%, and 9% for basil; 857%, 656%, and 92% for rocket; and 146%, 115%, and 28% for cress, respectively, compared to the control pots. The microstructure, elemental composition, surface area, thermal behaviour, and functional groups of the grown crystals were characterized using SEM, EDS, BET, TGA-DTG-DSC, and FTIR analyses, respectively. Flammability tests and thermal analyses concluded that the dried and crumbled/implanted form of struvite used as a fire-retardant barrier demonstrated a remarkable flame-resistant behaviour for both cotton fabric and wooden plate. Findings of this experimental study clearly corroborated the versatility of struvite as non-polluting and environmentally friendly clean product for the sustainable usage in different fields.

  13. Micronutrients as Impurities of Inorganic Fertilizers Marketed in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    A.S. Modaihsh

    2000-06-01

    Full Text Available Inorganic fertilizers with major nutrients are likely to be contaminated with some micronutrients. Fertilizers, utilized in Saudi Arabia, were analyzed for their total and water-soluble content of Fe, Zn, Mn and Cu. They represented three categories namely: phosphatic, solid multiple nutrient fertilizers (SMNF and water-soluble multiple nutrient fertilizers (WSMF. Total iron content in examined fertilizers was higher in phosphatic fertilizers and lower in WSMF. Nevertheless, only a very small portion of the total iron content is likely to be available to plants. It was estimated, on the basis of total content, that almost 2 g of iron would be applied to soil for each added kg of phosphatic fertilizer. The highest total content of Zn was recorded for phosphatic fertilizers. The data suggested that less than half kg of Zn would be accumulated in soil if 500 kg of phosphatic fertilizers were applied in one year. This value however, fell dramatically, to one fourth of the value, when only the available forms of Zn were considered. Fertilizer content of manganese and copper were lower than both Fe and Zn. Micronutrient impurities present in inorganic fertilizers might not have an immediate influence on plant nutrition due to their lower solubility.

  14. Monte Carlo simulations of the detailed iron absorption line profiles from thermal winds in X-ray binaries

    Science.gov (United States)

    Tomaru, Ryota; Done, Chris; Odaka, Hirokazu; Watanabe, Shin; Takahashi, Tadayuki

    2018-05-01

    Blueshifted absorption lines from highly ionized iron are seen in some high inclination X-ray binary systems, indicating the presence of an equatorial disc wind. This launch mechanism is under debate, but thermal driving should be ubiquitous. X-ray irradiation from the central source heats disc surface, forming a wind from the outer disc where the local escape velocity is lower than the sound speed. The mass-loss rate from each part of the disc is determined by the luminosity and spectral shape of the central source. We use these together with an assumed density and velocity structure of the wind to predict the column density and ionization state, then combine this with a Monte Carlo radiation transfer to predict the detailed shape of the absorption (and emission) line profiles. We test this on the persistent wind seen in the bright neutron star binary GX 13+1, with luminosity L/LEdd ˜ 0.5. We approximately include the effect of radiation pressure because of high luminosity, and compute line features. We compare these to the highest resolution data, the Chandra third-order grating spectra, which we show here for the first time. This is the first physical model for the wind in this system, and it succeeds in reproducing many of the features seen in the data, showing that the wind in GX13+1 is most likely a thermal-radiation driven wind. This approach, combined with better streamline structures derived from full radiation hydrodynamic simulations, will allow future calorimeter data to explore the detail wind structure.

  15. Using simulation to interpret a discrete time survival model in a complex biological system: fertility and lameness in dairy cows.

    Directory of Open Access Journals (Sweden)

    Christopher D Hudson

    Full Text Available The ever-growing volume of data routinely collected and stored in everyday life presents researchers with a number of opportunities to gain insight and make predictions. This study aimed to demonstrate the usefulness in a specific clinical context of a simulation-based technique called probabilistic sensitivity analysis (PSA in interpreting the results of a discrete time survival model based on a large dataset of routinely collected dairy herd management data. Data from 12,515 dairy cows (from 39 herds were used to construct a multilevel discrete time survival model in which the outcome was the probability of a cow becoming pregnant during a given two day period of risk, and presence or absence of a recorded lameness event during various time frames relative to the risk period amongst the potential explanatory variables. A separate simulation model was then constructed to evaluate the wider clinical implications of the model results (i.e. the potential for a herd's incidence rate of lameness to influence its overall reproductive performance using PSA. Although the discrete time survival analysis revealed some relatively large associations between lameness events and risk of pregnancy (for example, occurrence of a lameness case within 14 days of a risk period was associated with a 25% reduction in the risk of the cow becoming pregnant during that risk period, PSA revealed that, when viewed in the context of a realistic clinical situation, a herd's lameness incidence rate is highly unlikely to influence its overall reproductive performance to a meaningful extent in the vast majority of situations. Construction of a simulation model within a PSA framework proved to be a very useful additional step to aid contextualisation of the results from a discrete time survival model, especially where the research is designed to guide on-farm management decisions at population (i.e. herd rather than individual level.

  16. Dissolution of copper, tin, and iron from sintered tungsten-bronze spheres in a simulated avian gizzard, and an assessment of their potential toxicity to birds

    International Nuclear Information System (INIS)

    Thomas, Vernon G.; McGill, Ian R.

    2008-01-01

    The rates of dissolution of copper, tin, and iron from sintered tungsten-bronze spheres (51.1%W, 44.4%Cu, 3.9%Sn, 0.6%Fe, by mass) were measured in an in vitro simulated avian gizzard at pH 2.0, and 42C. Most of the spheres had disintegrated completely to a fine powder by day 14. Dissolution of copper, tin, and iron from the spheres was linear over time; all r > 0.974; all P < 0.001. The mean rate of release of copper, tin, and iron was 30.4 mg, 2.74 mg, and 0.38 mg per g tungsten-bronze per day, respectively. These rates of metal release were compared to those in published studies to determine whether the simultaneous ingestion of eight spheres of 3.48 mm diameter would pose a toxic risk to birds. The potential absorption rates of iron and tin (0.54 mg Fe/day, and 3.89 mg Sn/day) from eight tungsten-bronze spheres of total mass 1.42 g would not prove toxic, based on empirical studies of tin and iron ingestion in waterfowl. The release of 43.17 mg copper/day from eight tungsten-bronze spheres, while exceeding the daily copper requirements of domesticated birds, is far below the levels of copper known to cause copper toxicosis in birds. We conclude that sintered tungsten-bronze material made into gunshot, fishing weights, or wheel balance weights, would not pose a toxic risk to wild birds when ingested

  17. Forecasting carbon budget under climate change and CO2 fertilization for subtropical region in China using integrated biosphere simulator (IBIS) model

    Science.gov (United States)

    Zhu, Q.; Jiang, H.; Liu, J.; Peng, C.; Fang, X.; Yu, S.; Zhou, G.; Wei, X.; Ju, W.

    2011-01-01

    The regional carbon budget of the climatic transition zone may be very sensitive to climate change and increasing atmospheric CO2 concentrations. This study simulated the carbon cycles under these changes using process-based ecosystem models. The Integrated Biosphere Simulator (IBIS), a Dynamic Global Vegetation Model (DGVM), was used to evaluate the impacts of climate change and CO2 fertilization on net primary production (NPP), net ecosystem production (NEP), and the vegetation structure of terrestrial ecosystems in Zhejiang province (area 101,800 km2, mainly covered by subtropical evergreen forest and warm-temperate evergreen broadleaf forest) which is located in the subtropical climate area of China. Two general circulation models (HADCM3 and CGCM3) representing four IPCC climate change scenarios (HC3AA, HC3GG, CGCM-sresa2, and CGCM-sresb1) were used as climate inputs for IBIS. Results show that simulated historical biomass and NPP are consistent with field and other modelled data, which makes the analysis of future carbon budget reliable. The results indicate that NPP over the entire Zhejiang province was about 55 Mt C yr-1 during the last half of the 21st century. An NPP increase of about 24 Mt C by the end of the 21st century was estimated with the combined effects of increasing CO2 and climate change. A slight NPP increase of about 5 Mt C was estimated under the climate change alone scenario. Forests in Zhejiang are currently acting as a carbon sink with an average NEP of about 2.5 Mt C yr-1. NEP will increase to about 5 Mt C yr-1 by the end of the 21st century with the increasing atmospheric CO2 concentration and climate change. However, climate change alone will reduce the forest carbon sequestration of Zhejiang's forests. Future climate warming will substantially change the vegetation cover types; warm-temperate evergreen broadleaf forest will be gradually substituted by subtropical evergreen forest. An increasing CO2 concentration will have little

  18. Numerical Simulation of Brazing TiC Cermet to Iron with TiZrNiCu Filler Metal

    Institute of Scientific and Technical Information of China (English)

    Lixia ZHANG; Jicai FENG

    2004-01-01

    The maximum thermal stress and stress concentration zones of iron/TiC cermet joint during cooling were studied in this paper. The results showed that the shear stress on iron/TiC cermet joint concentrates on the interface tip and the maximum shear stress appears on the left tip of iron/TiZrNiCu interlace. Positive tensile stress on TiC cermet undersurface concentrates on both sides of TiC cermet and its value decreases during cooling. Negative tensile stress on TiC cermet undersurface concentrates on the center of TiC cermet and its value increases during cooling. Brazing temperature has little effect on the development and maximum thermal stress.

  19. Geohydrology and numerical simulation of groundwater flow in the central Virgin River Basin of Iron and Washington Counties, Utah

    Science.gov (United States)

    Heilweil, V.M.; Freethey, G.W.; Wilkowske, C.D.; Stolp, B.J.; Wilberg, D.E.

    2000-01-01

    Because rapid growth of communities in Washington and Iron Counties, Utah, is expected to cause an increase in the future demand for water resources, a hydrologic investigation was done to better understand ground-water resources within the central Virgin River basin. This study focused on two of the principal ground-water reservoirs within the basin: the upper Ash Creek basin ground-water system and the Navajo and Kayenta aquifer system.The ground-water system of the upper Ash Creek drainage basin consists of three aquifers: the uppermost Quaternary basin-fill aquifer, the Tertiary alluvial-fan aquifer, and the Tertiary Pine Valley monzonite aquifer. These aquifers are naturally bounded by the Hurricane Fault and by drainage divides. On the basis of measurements, estimates, and numerical simulations of reasonable values for all inflow and outflow components, total water moving through the upper Ash Creek drainage basin ground-water system is estimated to be about 14,000 acre-feet per year. Recharge to the upper Ash Creek drainage basin ground-water system is mostly from infiltration of precipitation and seepage from ephemeral and perennial streams. The primary source of discharge is assumed to be evapotranspiration; however, subsurface discharge near Ash Creek Reservoir also may be important.The character of two of the hydrologic boundaries of the upper Ash Creek drainage basin ground-water system is speculative. The eastern boundary provided by the Hurricane Fault is assumed to be a no-flow boundary, and a substantial part of the ground-water discharge from the system is assumed to be subsurface outflow beneath Ash Creek Reservoir along the southern boundary. However, these assumptions might be incorrect because alternative numerical simulations that used different boundary conditions also proved to be feasible. The hydrogeologic character of the aquifers is uncertain because of limited data. Differences in well yield indicate that there is considerable

  20. Experimental investigation and thermodynamic simulation of the uranium oxide-zirconium oxide-iron oxide system in air

    Czech Academy of Sciences Publication Activity Database

    Petrov, Y. B.; Udalov, Y. P.; Šubrt, Jan; Bakardjieva, Snejana; Sázavský, P.; Kiselová, M.; Selucký, P.; Bezdička, Petr; Joumeau, C.; Piluso, P.

    2011-01-01

    Roč. 37, č. 2 (2011), s. 212-229 ISSN 1087-6596 Institutional research plan: CEZ:AV0Z40320502 Keywords : uranium oxide * zirconium oxide * iron oxide * fusibility curve * oxygen partial pressure * crystallization * phase composition Subject RIV: CA - Inorganic Chemistry Impact factor: 0.492, year: 2011

  1. Will sex selection reduce fertility?

    Science.gov (United States)

    Leung, S F

    1994-01-01

    Population control is one of the primary policies applied against poverty in many low income countries. The widespread prevalence of son preference in some countries such as China and India, however, works against any reduction of fertility. This is so because parents often continue to have children until they obtain the number of sons which they desire. The bias against girls has also led to higher abortion and mortality rates of female children. It is frequently argued that if sex selection methods are made available to parents so that they can control the gender of their children, population growth would be lowered and women's welfare improved. The author investigates both theoretically and numerically the impact of sex selection on fertility. A static quantity-quality model of fertility is used to compare fertility choices when parents cannot choose the gender of children versus a situation in which parents can choose gender. Empirical data are drawn from the 1976 Malaysian Family Life Survey. Analysis found that whether sex selection reduces fertility depends upon the second and third derivatives of the utility function and the child expenditure function. A numerical dynamic analysis is also presented. The simulation shows, using empirical dynamic models of fertility and the Monte Carlo integration technique, that sex selection on the firstborn child among the Chinese in Malaysia could reduce fertility by about 3%.

  2. Fertility Clinic Success Rates

    Science.gov (United States)

    ... Defects ART and Autism 2013 Assisted Reproductive Technology Fertility Clinic Success Rates Report Recommend on Facebook Tweet ... Additional Information About ART in the United States. Fertility Clinic Tables Introduction to Fertility Clinic Tables [PDF - ...

  3. Fertility and Population Policy

    OpenAIRE

    Ouedraogo, Abdoulaye; Tosun, Mehmet S.; Yang, Jingjing

    2018-01-01

    There have been significant changes in both the fertility rates and fertility perception since 1970s. In this paper, we examine the relationship between government policies towards fertility and the fertility trends. Total fertility rate, defined as the number of children per woman, is used as the main fertility trend variable. We use panel data from the United Nations World Population Policies database, and the World Bank World Development Indicators for the period 1976 through 2013. We find...

  4. Organic iron (III) complexing ligands during an iron enrichment experiment in the western subarctic North Pacific

    Science.gov (United States)

    Kondo, Yoshiko; Takeda, Shigenobu; Nishioka, Jun; Obata, Hajime; Furuya, Ken; Johnson, William Keith; Wong, C. S.

    2008-06-01

    Complexation of iron (III) with natural organic ligands was investigated during a mesoscale iron enrichment experiment in the western subarctic North Pacific (SEEDS II). After the iron infusions, ligand concentrations increased rapidly with subsequent decreases. While the increases of ligands might have been partly influenced by amorphous iron colloids formation (12-29%), most in-situ increases were attributable to the Dilution of the fertilized patch may have contributed to the rapid decreases of the ligands. During the bloom decline, ligand concentration increased again, and the high concentrations persisted for 10 days. The conditional stability constant was not different between inside and outside of the fertilized patch. These results suggest that the chemical speciation of the released iron was strongly affected by formation of the ligands; the production of ligands observed during the bloom decline will strongly impact the iron cycle and bioavailability in the surface water.

  5. Contribution of soil-32P, fertilizer-32P and VA mycorrhizal fungi to phosphorus nutrition of corn plant

    International Nuclear Information System (INIS)

    Feng Gu; Yang Maoqiu; Bai Dengsha; Huang Quansheng

    1997-01-01

    32 P labelled fertilizer and five synthetic phosphates (dicalcium phosphate, octocalcium phosphate, iron phosphate, aluminium phosphate and apatite), which were used to simulate inorganic phosphates such as Ca 2 -P, Ca 8 -P, Fe P , Al-P and Ca 10 -P in calcareous soil, were applied to corn plants inoculating with and without vesicular-arbuscular (VA) mycorrhizal fungi in a calcareous soil. The results showed that VA mycorrhizal fungi and dicalcium phosphate, octocalcium phosphate, iron phosphate, aluminium phosphate promoted growth and increased phosphorus content of corn plant. The four synthetic phosphates except apatite had higher contributions to corn plant growth than VA mycorrhizal fungi. Contributions of fertilizer-P, soil-P and synthetic phosphates to phosphorus nutrition of corn plant were in order of synthetic phosphates (except apatite) > soil- P > fertilizer-P. Inoculating with VA mycorrhizal fungi increased the contribution of soil-P and decreased the contribution of synthetic phosphates, but did not affect the contribution of fertilizer-P

  6. Dry corrosion prediction of radioactive waste containers in long term interim storage: mechanisms of low temperature oxidation of pure iron and numerical simulation of an oxide scale growth

    International Nuclear Information System (INIS)

    Bertrand, N.

    2006-10-01

    In the framework of research on long term behaviour of radioactive waste containers, this work consists on the one hand in the study of low temperature oxidation of iron and on the other hand in the development of a numerical model of oxide scale growth. Isothermal oxidation experiments are performed on pure iron at 300 and 400 C in dry and humid air at atmospheric pressure. Oxide scales formed in these conditions are characterized. They are composed of a duplex magnetite scale under a thin hematite scale. The inner layer of the duplex scale is thinner than the outer one. Both are composed of columnar grains, that are smaller in the inner part. The outer hematite layer is made of very small equiaxed grains. Markers and tracers experiments show that a part of the scale grows at metal/oxide interface thanks to short-circuits diffusion of oxygen. A model for iron oxide scale growth at low temperature is then deduced. Besides this experimental study, the numerical model EKINOX (Estimation Kinetics Oxidation) is developed. It allows to simulate the growth of an oxide scale controlled by mixed mechanisms, such as anionic and cationic vacancies diffusion through the scale, as well as metal transfer at metal/oxide interface. It is based on the calculation of concentration profiles of chemical species and also point defects in the oxide scale and in the substrate. This numerical model does not use the classical quasi-steady-state approximation and calculates the future of cationic vacancies at metal/oxide interface. Indeed, these point defects can either be eliminated by interface motion or injected in the substrate, where they can be annihilated, considering sinks as the climb of dislocations. Hence, the influence of substrate cold-work can be investigated. The EKINOX model is validated in the conditions of Wagner's theory and is confronted with experimental results by its application to the case of high temperature oxidation of nickel. (author)

  7. Fluence dependent changes of erosion yields and surface morphology of the iron-tungsten model system: SDTrimSP-2D simulation studies

    Directory of Open Access Journals (Sweden)

    U. von Toussaint

    2017-08-01

    Full Text Available The effect of different sample structures of an iron-tungsten model system (as a surrogate for reduced activation ferritic martensitic steels like EUROFER on the development of surface morphologies, tungsten surface enrichment and sputter yields under low-energy monoenergetic perpendicular 200 eV deuterium bombardment has been studied with SDTrimSP-2d simulations. Previous modeling studies considering diffusive effects also could reasonably reproduce and explain the experimental results for a large set of experimental parameters like temperature, flux and sample concentration. However, for settings with negligible Fe-W-interdiffusion the fluence needed for steady-state conditions differed between the experiments and the simulations. Thus, the main focus of the present study is directed towards the elucidation of this fluence mismatch. Comparison of one and two-dimensional simulation results reveal a strong dependency of the tungsten enrichment on the sample homogeneity and a significantly delayed reduction of the erosion yield due to a pronounced formation of surface structures from initially flat sample surfaces.

  8. [Nutrition and fertility].

    Science.gov (United States)

    Szostak-Węgierek, Dorota

    2011-01-01

    There is a growing body of evidence that nutritional habits may have a significant effect on both male and female fertility. Maintenance of normal body mass may be effective in the prevention of infertility resulting from ovulatory disorders. Underweight and, to a larger degree, overweight and/or obesity, are related to the enhanced risk of infertility. Insulin resistance is an important pathogenic mechanism that may impair ovulation. Adequate intake of monounsaturated fatty acids, derived mainly from vegetable fats, as well as avoidance of trans isomers of unsaturated fatty acids which are present in industrially produced cakes and sweets, crisps, fast-foods, powdered soups and hard margarines, may be effective in the prevention of infertility in females. Choice of plant rather than animal sources of proteins, decrease in glycemic load of the diet, use of dietary supplements containing iron and folic acid, could also be beneficial. Avoidance of vitamin B12 deficiency and its supplementation seem to be important in the prevention of early miscarriages. Sufficient intake of antioxidants also promotes female reproductive functions. Free radical processes play an important role in the development of male factor infertility. It was shown that proper intake or supplementation with antioxidants may be effective in its prevention and treatment. Such nutrients as zinc, selenium and folic acid act beneficially on sperm quality. A well-balanced diet seems to play an important role in the prevention of infertility in both sexes.

  9. Global Fertilizer and Manure, Version 1: Nitrogen Fertilizer Application

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nitrogen Fertilizer Application dataset of the Global Fertilizer and Manure, Version 1 Data Collection represents the amount of nitrogen fertilizer nutrients...

  10. Global Fertilizer and Manure, Version 1: Phosphorus Fertilizer Application

    Data.gov (United States)

    National Aeronautics and Space Administration — The Phosphorus Fertilizer Application dataset of the Global Fertilizer and Manure, Version 1 Data Collection represents the amount of phosphorus fertilizer nutrients...

  11. Treatment of simulated wastewater containing Reactive Red 195 by zero-valent iron/activated carbon combined with microwave discharge electrodeless lamp/sodium hypochlorite.

    Science.gov (United States)

    Fu, Jie; Xu, Zhen; Li, Qing-Shan; Chen, Song; An, Shu-Qing; Zeng, Qing-Fu; Zhu, Hai-Liang

    2010-01-01

    A comparative study of treatment of simulated wastewater containing Reactive Red 195 using zero-valent iron/activated carbon (ZVI/AC), microwave discharge electrodeless lamp/sodium hypochlorite (MDEL/NaClO) and the combination of ZVI/AC-MDEL/NaClO was conducted. The preliminary results showed the two steps method of ZVI/AC-MDEL/NaClO had much higher degradation efficiency than both single steps. The final color removal percentage was nearly up to 100% and the chemical oxygen demand reduction percentage was up to approximately 82%. The effects of operational parameters, including initial pH value of simulated wastewater, ZVI/AC ratio and particle size of ZVI were also investigated. In addition, from the discussion of synergistic effect between ZVI/AC and MEDL/NaClO, we found that in the ZVI/AC-MEDL/NaClO process, ZVI/AC could break the azo bond firstly and then MEDL/NaClO degraded the aromatic amine products effectively. Reversing the order would reduce the degradation efficiency.

  12. Carbon sequestration by patch fertilization: A comprehensive assessment using coupled physical-ecological-biogeochemical models: FINAL REPORT of grant Grant No. DE-FG02-04ER63726

    Energy Technology Data Exchange (ETDEWEB)

    Sarmiento, Jorge L; Gnanadesikan, Anand; Gruber, Nicolas

    2007-06-21

    the first three years of our project, led to several major new insights on the interaction between ocean biogeochemistry and circulation. This work, which is described in 2 the following Section II on “Large scale fertilization,” has continued to appear in the literature over the past few years, including two high visibility papers in Nature. Early on in the first three years of our project, it became clear that small "patch-scale" fertilizations over limited regions of order 100 km diameter were much more likely than large scale fertilization, and we carried out a series of idealized patch fertilization simulations reported on in Gnanadesikan et al. (2003). Based on this paper and other results we had obtained by the end of our first three-year grant, we identified a number of important issues that needed to be addressed in the second three-year period of this grant. Section III on “patch fertilization” discusses the major findings of this phase of our research, which is described in two major manuscripts that will be submitted for publication in the near future. This research makes use of new more realistic ocean ecosystem and iron cycling models than our first paper on this topic. We have several major new insights into what controls the efficiency of iron fertilization in the ocean. Section IV on “model development” summarizes a set of papers describing the progress that we made on improving the ecosystem models we use for our iron fertilization simulations.

  13. Simulations of iron K pre-edge X-ray absorption spectra using the restricted active space method.

    Science.gov (United States)

    Guo, Meiyuan; Sørensen, Lasse Kragh; Delcey, Mickaël G; Pinjari, Rahul V; Lundberg, Marcus

    2016-01-28

    The intensities and relative energies of metal K pre-edge features are sensitive to both geometric and electronic structures. With the possibility to collect high-resolution spectral data it is important to find theoretical methods that include all important spectral effects: ligand-field splitting, multiplet structures, 3d-4p orbital hybridization, and charge-transfer excitations. Here the restricted active space (RAS) method is used for the first time to calculate metal K pre-edge spectra of open-shell systems, and its performance is tested against on six iron complexes: [FeCl6](n-), [FeCl4](n-), and [Fe(CN)6](n-) in ferrous and ferric oxidation states. The method gives good descriptions of the spectral shapes for all six systems. The mean absolute deviation for the relative energies of different peaks is only 0.1 eV. For the two systems that lack centrosymmetry [FeCl4](2-/1-), the ratios between dipole and quadrupole intensity contributions are reproduced with an error of 10%, which leads to good descriptions of the integrated pre-edge intensities. To gain further chemical insight, the origins of the pre-edge features have been analyzed with a chemically intuitive molecular orbital picture that serves as a bridge between the spectra and the electronic structures. The pre-edges contain information about both ligand-field strengths and orbital covalencies, which can be understood by analyzing the RAS wavefunction. The RAS method can thus be used to predict and rationalize the effects of changes in both the oxidation state and ligand environment in a number of hard X-ray studies of small and medium-sized molecular systems.

  14. Male Fertility Issues

    Science.gov (United States)

    Fertility issues are common in boys and men getting cancer treatment. Fertility preservation options include sperm banking, testicular shielding, testicular sperm extraction (TESE), and testicular tissue freezing. Support and clinical trials are listed.

  15. The effects of foliar fertilization with iron sulfate in chlorotic leaves are limited to the treated area. A study with peach trees (Prunus persica L. Batsch grown in the field and sugar beet (Beta vulgaris L. grown in hydroponics

    Directory of Open Access Journals (Sweden)

    Hamdi eEl-Jendoubi

    2014-01-01

    Full Text Available Crop Fe deficiency is a worldwide problem. The aim of this study was to assess the effects of foliar Fe applications in two species grown in different environments: peach (Prunus persica L. Batsch trees grown in the field and sugar beet (Beta vulgaris L. cv. ‘Orbis’ grown in hydroponics. The distal half of Fe-deficient, chlorotic leaves was treated with Fe sulfate by dipping and using a brush in peach trees and sugar beet plants, respectively. The re-greening of the distal (Fe-treated and basal (untreated leaf areas was monitored, and the nutrient and photosynthetic pigment composition of the two areas were also determined. Leaves were also studied using chlorophyll fluorescence imaging, low temperature-scanning electron microscopy microanalysis, scanning transmission ion microscopy-particle induced X-ray emission and Perls Fe staining. The distal, Fe-treated leaf parts of both species showed a significant increase in Fe concentrations (across the whole leaf volume and marked re-greening, with significant increases in the concentrations of all photosynthetic pigments, as well as decreases in de-epoxidation of xanthophyll cycle carotenoids and increases in photochemical efficiency. In the basal, untreated leaf parts, Fe concentrations increased slightly, but little re-greening occurred. No changes in the concentrations of other nutrients were found. Foliar Fe fertilization was effective in re-greening treated leaf areas both in peach trees and sugar beet plants. Results indicate that the effects of foliar Fe-sulfate fertilization in Fe-deficient, chlorotic leaves were minor outside the leaf surface treated, indicating that Fe mobility within the leaf is a major constraint for full fertilizer effectiveness in crops where Fe-deficiency is established and leaf chlorosis occurs.

  16. The effects of foliar fertilization with iron sulfate in chlorotic leaves are limited to the treated area. A study with peach trees (Prunus persica L. Batsch) grown in the field and sugar beet (Beta vulgaris L.) grown in hydroponics.

    Science.gov (United States)

    El-Jendoubi, Hamdi; Vázquez, Saúl; Calatayud, Angeles; Vavpetič, Primož; Vogel-Mikuš, Katarina; Pelicon, Primož; Abadía, Javier; Abadía, Anunciación; Morales, Fermín

    2014-01-01

    Crop Fe deficiency is a worldwide problem. The aim of this study was to assess the effects of foliar Fe applications in two species grown in different environments: peach (Prunus persica L. Batsch) trees grown in the field and sugar beet (Beta vulgaris L. cv. "Orbis") grown in hydroponics. The distal half of Fe-deficient, chlorotic leaves was treated with Fe sulfate by dipping and using a brush in peach trees and sugar beet plants, respectively. The re-greening of the distal (Fe-treated) and basal (untreated) leaf areas was monitored, and the nutrient and photosynthetic pigment composition of the two areas were also determined. Leaves were also studied using chlorophyll fluorescence imaging, low temperature-scanning electron microscopy microanalysis, scanning transmission ion microscopy-particle induced X-ray emission and Perls Fe staining. The distal, Fe-treated leaf parts of both species showed a significant increase in Fe concentrations (across the whole leaf volume) and marked re-greening, with significant increases in the concentrations of all photosynthetic pigments, as well as decreases in de-epoxidation of xanthophyll cycle carotenoids and increases in photochemical efficiency. In the basal, untreated leaf parts, Fe concentrations increased slightly, but little re-greening occurred. No changes in the concentrations of other nutrients were found. Foliar Fe fertilization was effective in re-greening treated leaf areas both in peach trees and sugar beet plants. Results indicate that the effects of foliar Fe-sulfate fertilization in Fe-deficient, chlorotic leaves were minor outside the leaf surface treated, indicating that Fe mobility within the leaf is a major constraint for full fertilizer effectiveness in crops where Fe-deficiency is established and leaf chlorosis occurs.

  17. Cast irons

    CERN Document Server

    1996-01-01

    Cast iron offers the design engineer a low-cost, high-strength material that can be easily melted and poured into a wide variety of useful, and sometimes complex, shapes. This latest handbook from ASM covers the entire spectrum of one of the most widely used and versatile of all engineered materials. The reader will find the basic, but vital, information on metallurgy, solidification characteristics, and properties. Extensive reviews are presented on the low-alloy gray, ductile, compacted graphite, and malleable irons. New and expanded material has been added covering high-alloy white irons used for abrasion resistance and high-alloy graphitic irons for heat and corrosion resistance. Also discussed are melting furnaces and foundry practices such as melting, inoculation, alloying, pouring, gating and rising, and molding. Heat treating practices including stress relieving, annealing, normalizing, hardening and tempering, autempering (of ductile irons), and surface-hardening treatments are covered, too. ASM Spec...

  18. Selection of suitable fertilizer draw solute for a novel fertilizer-drawn forward osmosis-anaerobic membrane bioreactor hybrid system

    KAUST Repository

    Kim, Youngjin

    2016-02-09

    In this study, a protocol for selecting suitable fertilizer draw solute for anaerobic fertilizer-drawn forward osmosis membrane bioreactor (AnFDFOMBR) was proposed. Among eleven commercial fertilizer candidates, six fertilizers were screened further for their FO performance tests and evaluated in terms of water flux and reverse salt flux. Using selected fertilizers, bio-methane potential experiments were conducted to examine the effect of fertilizers on anaerobic activity due to reverse diffusion. Mono-ammonium phosphate (MAP) showed the highest biogas production while other fertilizers exhibited an inhibition effect on anaerobic activity with solute accumulation. Salt accumulation in the bioreactor was also simulated using mass balance simulation models. Results showed that ammonium sulphate and MAP were the most appropriate for AnFDFOMBR since they demonstrated less salt accumulation, relatively higher water flux, and higher dilution capacity of draw solution. Given toxicity of sulphate to anaerobic microorganisms, MAP appears to be the most suitable draw solution for AnFDFOMBR.

  19. Cancer and fertility: strategies to preserve fertility.

    Science.gov (United States)

    Diedrich, K; Fauser, B C J M; Devroey, P

    2011-03-01

    Fertility preservation is a key component of cancer management in young people. The Fourth Evian Annual Reproduction Workshop Meeting was held in April 2009 to discuss cancer and fertility in young adults. Specialists in oncology, assisted reproduction, embryology and clinical genetics presented published data and ongoing research on cancer and fertility, with particular focus on strategies to preserve fertility. This report is based on the expert presentations and group discussions, supplemented with publications from literature searches and the authors' knowledge. Fertility preservation should be considered for all young people undergoing potentially gonadotoxic cancer treatment. A variety of options are required to facilitate safe and effective fertility preservation for individual patients. Sperm banking is a simple and low-cost intervention. Embryo cryopreservation is the only established method of female fertility preservation. Oocyte cryopreservation offers a useful option for women without a male partner. Emergency ovarian stimulation and cryopreservation of ovarian tissue (followed by tissue transplantation or in-vitro maturation of oocytes) are experimental techniques for women who require urgent cancer treatment. Further prospective studies are required to validate cryopreservation of oocytes and ovarian tissue, in-vitro maturation of oocytes and new vitrification techniques and to identify any long-term sequelae of slow freezing of embryos. Copyright © 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  20. Changes in the concentration of iron in different size fractions during an iron enrichment experiment in the open Southern Ocean

    NARCIS (Netherlands)

    Nishioka, Jun; Takeda, Shigenobu; Baar, Hein J.W. de; Croot, Peter L.; Boye, Marie; Laan, Patrick; Timmermans, Klaas R.

    2005-01-01

    An in situ iron enrichment experiment was carried out in the Southern Ocean Polar Frontal Zone and fertilized a patch of water within an eddy of the Antarctic Circumpolar Current (EisenEx, Nov. 2000). During the experiment, a physical speciation technique was used for iron analysis in order to

  1. Effect of replacement of vanadium by iron on the electrochemical behaviour of titanium alloys in simulated physiological media

    Directory of Open Access Journals (Sweden)

    Mareci, D.

    2009-02-01

    Full Text Available The electrochemical behaviour of Ti6Al4V, Ti6Al3.5Fe and Ti5Al2.5Fe alloys has been evaluated in Ringer’s solution at 25 °C. The effect of the substitution of vanadium in Ti6Al4V alloy has been specifically addressed. The evaluation of the corrosion resistance was carried out through the analysis of the open circuit potential variation with time, potentiodynamic polarization curves, and electrochemical impedance spectroscopy (EIS tests. Very low current densities were obtained (order of nA/cm2 from the polarization curves and EIS, indicating a typical passive behaviour for all investigated alloys. The EIS results exhibited relative capacitive behaviour (large corrosion resistance with phase angle close to –80° and relative high impedance values (order of 105 Ω•cm2 at low and medium frequencies, which are indicative of the formation of a highly stable film on these alloys in Ringer’s solution. In conclusion, the electrochemical behaviour of Ti6Al4V is not affected by the substitution of vanadium with iron.

    El comportamiento electroquímico de las aleaciones Ti6Al4V, Ti6Al3.5Fe y Ti5Al2.5Fe fue evaluado en una disolución Ringer a 25 °C. Se ha estudiado especialmente el efecto de la sustitución del vanadio en la aleación Ti6Al4V. La evaluación de la resistencia a la corrosión se ha llevado a cabo a través del análisis de la variación del potencial de un circuito abierto con el tiempo, las curvas de polarización potenciodinámicas y los ensayos de espectroscopía de impedancia electroquímica (EIS. Se han obtenido densidades de corriente muy bajas (del orden de nA/cm2 en las curvas de polarización y EIS, indicando un comportamiento pasivo típico para todas las aleaciones investigadas. Los resultados de la EIS mostraron un comportamiento capacitivo relativo (gran resistencia a la corrosión con ángulos de fase próximos a –80° y valores de impedancia relativamente altos (del orden de

  2. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... risk for iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, ... iron-fortified foods that have iron added. Vegetarian diets can provide enough iron if you choose nonmeat ...

  3. Nutrient uptake of NPK and result of some rice varieties in tidal land by using combination of organic and inorganic fertilizer

    Science.gov (United States)

    Marlina, Neni; Rompas, Joni Phillep; Marlina, Musbik

    2017-09-01

    Rice planting in tidal land has two main problems: iron (Fe) which has the potential to poison rice and low nutrient availability. Azospirillum enriched chicken manure and phosphate solvent bacteria (Biological Organic Fertilizer = BOF) is an option to overcome iron toxicity and as a source of nutrition. The objective of the study was to obtain a combination of biological organic fertilizers and balanced inorganic fertilizers in reducing doses of inorganic fertilizers, increasing NPK nutrient uptake and yield of several rice varieties in tidal land. This research used Factorial RAK with 25 treatment combinations that were repeated three times. Factor I is a combination of BOF and anorganic fertilizer with 5 levels of treatment (no inorganic fertilizers, BOF 400 kg / ha with inorganic fertilizer 25% NPK, BOF 400 kg / ha with inorganic fertilizer 50% NPK and BOF 400 kg / ha with fertilizer Inorganic 75% NPK). Factor II is several rice varieties (IPB 4S, Martapura, Margasari, Inpara 5, Inpara 7). The results showed that organic fertilizer 400 kg / ha can reduce the use of inorganic fertilizer by 75% of NPK fertilizer. The highest NPK nutrient absorption is in the treatment of organic fertilizer 400 kg / ha and inorganic fertilizer 25% of NPK fertilizer. Production of biological organic fertilizer 400 kg / ha with inorganic fertilizer 25% NPK and 4B IPB varieties 727.77% higher when compared with without the provision of organic fertilizer with Inpara 5 varieties.

  4. Microstructure modeling and crystal plasticity simulations for the evaluation of fatigue crack initiation in α-iron specimen including an elliptic defect

    Energy Technology Data Exchange (ETDEWEB)

    Briffod, Fabien, E-mail: briffod@rme.mm.t.u-tokyo.ac.jp; Shiraiwa, Takayuki; Enoki, Manabu

    2017-05-17

    In this study, fatigue crack initiation in pure α-iron is investigated through a microstructure-sensitive framework. At first, synthetic microstructures are modeled based on an anisotropic tessellation that accounts for the information of the grains morphology extracted from electron backscatter diffraction (EBSD) analysis. Low-cycle fatigue experiments under strain-controlled conditions are conducted in order to calibrate a crystal plasticity model and a J{sub 2} model including isotropic and kinematic hardening. A critical plane fatigue indicator parameter (FIP) based on the Tanaka-Mura model is then presented to evaluate the location and quantify the driving force for the formation of a crack. The FIP is averaged over several potential crack paths within each grain defined by the intersection between a given slip plane and the plane of the model thus accounting for both the lattice orientation and morphology of the grain. Several fatigue simulations at various stress amplitudes are conducted using a sub-modeling technique for the attribution of boundary conditions on the polycrystalline aggregate models including an elliptic defect. The influence of the microstructure attributes and stress level on the location and amplitude of the FIP are then quantified and discussed.

  5. PERSPECTIVE: Dust, fertilization and sources

    Science.gov (United States)

    Remer, Lorraine A.

    2006-11-01

    depression combined with the prevailing wind direction in the winter provides perfect conditions for aerosol saltation, uplift and transport. The winter Bodélé dust is carried over the populated regions of west Africa where it can be affected by smoke and urban pollution before it continues transport over the Atlantic and towards Amazonia. Although Koren et al do not speculate on the chemical possibilities in their paper, the interaction between the dust and the pollutants provides opportunity for acids to coat the dust particles and to mobilize the iron compounds, creating a highly efficient fertilizing agent for ocean phytoplankton and the biota of the Amazon forest. Koren et al do quantify the dust emission of the Bodélé depression, estimating that this small area produces approximately 50% of the Saharan dust deposited in the Amazon. The findings of Koren and his co-authors suggest that dust emission sources may be highly localized spots in the Earth's deserts that can be mapped precisely by satellites of moderate to fine resolution. Like fire hot spots that localize smoke emission, desert dust hot spots can be identified with great detail. This can provide aerosol transport models with better source emission information and improve estimates that will help in making estimates concerning biogeochemical processes and also estimates of climate forcing and response. References [1] Swap R et al 1992 Saharan dust in the Amazon basin Tellus B 44 133-49 (doi:10.1034/j.1600-0889.1992.t01-1-00005.x) [2] Kaufman Y J, Koren I, Remer L A, Tanré D, Ginoux P and Fan S 2005 Dust transport and deposition observed from the Terra-MODIS space observations J. Geophys. Res. 110 D10S12 (doi:10.1029/2003JD004436) [3] Meskhidze N, Chameides W L and Nenes A 2005 Dust and pollution: a recipe for enhanced ocean fertizilation? J. Geophys. Res. 110 (D3) D03301 (doi:10.1029/2004JD005082) [4] Cakur R V et al 2006 Constraining the magnitude of the global dust cycle by minimizing the difference

  6. IRON DOME

    African Journals Online (AJOL)

    6 Israeli Navy 'First Arm of the Sea: The Successful Interception of the Iron Dome Rocket .... sky to destroy them whilst in flight to minimise civilian casualties. ..... Including The Moon and Celestial Bodies.53 Demeyere further emphasises the.

  7. Iron overdose

    Science.gov (United States)

    ... tracing) X-ray to detect and track iron tablets through the stomach and intestines Treatment may include: ... BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ed. Philadelphia, PA: Elsevier; 2016: ...

  8. Simulations

    CERN Document Server

    Ngada, Narcisse

    2015-06-15

    The complexity and cost of building and running high-power electrical systems make the use of simulations unavoidable. The simulations available today provide great understanding about how systems really operate. This paper helps the reader to gain an insight into simulation in the field of power converters for particle accelerators. Starting with the definition and basic principles of simulation, two simulation types, as well as their leading tools, are presented: analog and numerical simulations. Some practical applications of each simulation type are also considered. The final conclusion then summarizes the main important items to keep in mind before opting for a simulation tool or before performing a simulation.

  9. Effect of organic and inorganic fertilizers on nutrient concentrations ...

    African Journals Online (AJOL)

    Effect of organic and inorganic fertilizers on nutrient concentrations in plantain ( Musa spp.) ... Fruit parameters measured were fruit weight, edible proportion and pulp dry matter content; also, the concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), iron (Fe) and zinc (Zn) in fruits were determined.

  10. [Fertility transition in Peru].

    Science.gov (United States)

    Ferrando, D; Aramburu, C E

    1992-12-01

    Data from national censuses and sample surveys are the basis for this examintion of differential fertility and the fertility transition in Peru. Changes in the level and structure of fertility in the 3 major geographic regions are compared, and the role of contraceptive usage and nuptiality changes in the fertility decline are analyzed. Peru's total fertility rate was estimated at 6.85 in 1965 and has since declined to 6.56 in 1965-70, 6.00 in 1970-75, 5.30 in 1975-80, 4.65 in 1980-85, and 4.00 in 1985-90. The fertility decline varied in intensity and timing in the geographic regions. A clear fertility decline began among upper and middle income groups in the principal cities in the 1960s, spreading gradually to the urban low income sectors. Not until the late 1970s did the fertility decline spread to the rest of the population, coinciding with the years of severe economic crisis. The urban total fertility rate declined from 6 to 3.77 during 1961-86, but rural fertility increased through 1972 to 8.12, before declining slightly to 7.62 in 1981 and more markedly to 6.65 in 1986. Sociocultural and economic differences between Peru's natural regions are appreciable, and account for the contrasts in fertility trends. The greatest changes occurred in metropolitan Lima, which already had relatively low fertility in 1961. Its total fertility rate declined 44% from 5.6 in 1961 to 3.13 in 1986. Fertility declined by slightly under 40% in the rest of the coast, by almost 25% in the jungle, and by scarcely 14% in the sierra. The total fertility rates in 1961 and 1986, respectively, were 6.38 and 4.13 on the coast, 6.64 and 6.45 in the highlands, and 7.92 and 5.97 in the lowlands. The fertility decline, especially in the lower classes, was a response initially to the process of cultural modernization which in slightly over 2 decades saw a profound transformation of Peru from a rural, Andean, illiterate, and agrarian society to an urban, coastal, literate, and commercial society

  11. Protect Your Fertility

    Science.gov (United States)

    ... your teens and early twenties can affect your fertility for years to come. This prevention guide was written by ... loss of testic- ulor size, see your doctor. Fertility is something that you ... approximately 40 percent of infertile couples, the male partner is ...

  12. Fertilization in northern forests

    DEFF Research Database (Denmark)

    Hedwall, Per Ola; Gong, Peichen; Ingerslev, Morten

    2014-01-01

    resources into food, health and industrial products and energy. Fertilization in Sweden and Finland is currently practiced by extensive fertilization regimens where nitrogen fertilizers are applied once, or up to three times, during a rotation period, mainly in mature forest. This type of fertilization...... gives, in most cases, a small and transient effect on the environment as well as a high rate of return to the forest owner with low-economic risk. The increase in biomass production, however, is relatively small and consequently the impact on the processing industry and the bioeconomy is limited. More...... in combination with present management systems and, almost instantly, enhances forest productivity. There may, however, be both economic and environmental constraints to large-scale applications of fertilizers in forest. Here we review the literature concerning biomass production of forests under different...

  13. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... iron-rich foods, especially during certain stages of life when more iron is needed, such as childhood and pregnancy. Good sources of iron are meat, poultry, fish, and iron- ...

  14. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... that are good sources of iron include dried beans, dried fruits, eggs, lean red meat, salmon, iron- ... of iron, including iron-fortified breads and cereals, beans, tofu, dried fruits, and spinach and other dark ...

  15. Iron in diet

    Science.gov (United States)

    ... Reasonable amounts of iron are also found in lamb, pork, and shellfish. Iron from vegetables, fruits, grains, ... strawberries, tomatoes, and potatoes) also increase iron absorption. Cooking foods in a cast-iron skillet can also ...

  16. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... from developing iron-deficiency anemia. Foods that are good sources of iron include dried beans, dried fruits, ... iron is needed, such as childhood and pregnancy. Good sources of iron are meat, poultry, fish, and ...

  17. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... you are diagnosed with iron-deficiency anemia. Risk Factors You may have an increased risk for iron- ... iron-deficiency anemia if you have certain risk factors , including pregnancy. To prevent iron-deficiency anemia, your ...

  18. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... for your body to absorb iron from the gastrointestinal tract (GI tract). Blood loss When you lose blood, ... iron deficiency. Endurance athletes lose iron through their gastrointestinal tracts. They also lose iron through the breakdown of ...

  19. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... iron in your body is low. For this reason, other iron tests are also done. Ferritin measure ... iron is needed, such as childhood and pregnancy. Good sources of iron are meat, poultry, fish, and ...

  20. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... develop new therapies for conditions that affect the balance of iron in the body and lead to ... Disease Control and Prevention) Iron - Health Professional Fact Sheet (NIH) Iron Dietary Supplement Fact Sheet (NIH) Iron- ...

  1. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... to moderate iron-deficiency anemia, or red blood cell transfusion for severe iron-deficiency anemia. You may ... body needs iron to make healthy red blood cells. Iron-deficiency anemia usually develops over time because ...

  2. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... enough iron-rich foods, such as meat and fish, may result in you getting less than the ... pregnancy. Good sources of iron are meat, poultry, fish, and iron-fortified foods that have iron added. ...

  3. Iron Dextran Injection

    Science.gov (United States)

    Iron dextran injection is used to treat iron-deficiency anemia (a lower than normal number of red blood cells ... treated with iron supplements taken by mouth. Iron dextran injection is in a class of medications called ...

  4. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... and severity. Treatments may include iron supplements, procedures, surgery, and dietary ... iron supplements, also called iron pills or oral iron, by mouth once or several times a ...

  5. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... developing iron-deficiency anemia. Foods that are good sources of iron include dried beans, dried fruits, eggs, ... is needed, such as childhood and pregnancy. Good sources of iron are meat, poultry, fish, and iron- ...

  6. Iron deficiency

    DEFF Research Database (Denmark)

    Schou, Morten; Bosselmann, Helle; Gaborit, Freja

    2015-01-01

    BACKGROUND: Both iron deficiency (ID) and cardiovascular biomarkers are associated with a poor outcome in heart failure (HF). The relationship between different cardiovascular biomarkers and ID is unknown, and the true prevalence of ID in an outpatient HF clinic is probably overlooked. OBJECTIVES.......043). CONCLUSION: ID is frequent in an outpatient HF clinic. ID is not associated with cardiovascular biomarkers after adjustment for traditional confounders. Inflammation, but not neurohormonal activation is associated with ID in systolic HF. Further studies are needed to understand iron metabolism in elderly HF...

  7. Long-Term Effect of a Leonardite Iron Humate Improving Fe Nutrition As Revealed in Silico, in Vivo, and in Field Experiments.

    Science.gov (United States)

    Cieschi, María T; Caballero-Molada, Marcos; Menéndez, Nieves; Naranjo, Miguel A; Lucena, Juan J

    2017-08-09

    Novel, cheap and ecofriendly fertilizers that solve the usual iron deficiency problem in calcareous soil are needed. The aim of this work is to study the long-term effect of an iron leonardite fertilizer on citrus nutrition taking into account a properly characterization, kinetic response with a ligand competition experiment, efficiency assessment using Saccharomyces cerevisiae strain and finally, in field conditions with citrus as test plants. Its efficiency was compared with the synthetic iron chelate FeEDDHA. Leonardite iron humate (LIH) is mainly humic acid with a high-condensed structure where iron is present as ferrihydrite and Fe 3+ polynuclear compounds stabilized by organic matter. Iron and humic acids form aggregates that decrease the iron release from these kinds of fertilizers. Furthermore, LIH repressed almost 50% of the expression of FET3, FTR1, SIT1, and TIS11 genes in Saccharomyces cerevisiae cells, indicating increasing iron provided in cells and improved iron nutrition in citrus.

  8. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Research Home / < Back To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español Iron-deficiency ... iron-deficiency anemia. Blood tests to screen for iron-deficiency anemia To screen for iron-deficiency anemia, your doctor ...

  9. Oral Iron Prophylaxis in Pregnancy: Not Too Little and Not Too Much!

    Directory of Open Access Journals (Sweden)

    Nils Milman

    2012-01-01

    Full Text Available An adequate supply of iron is essential for normal development of the fetus and newborn child. Iron deficiency and iron deficiency anemia (IDA during pregnancy increase the risk of preterm birth and low birth weight. Iron is important for development of the fetal brain and cognitive abilities of the newborn. Children born to iron-deficient mothers will start their lives suffering from iron deficiency or even IDA. Oral iron prophylaxis to pregnant women improves iron status and prevents development of IDA. The Danish National Board of Health has since 1992 recommended prophylactic oral iron supplements to all pregnant women and the currently advocated dose is 40–50 mg ferrous iron taken between meals from 10 weeks gestation to delivery. However, 30–40 mg ferrous iron is probably an adequate dose in most affluent societies. In developed countries, individual iron prophylaxis guided by iron status (serum ferritin has physiological advantages compared to general iron prophylaxis. In contrast, in most developing countries, general iron prophylaxis is indicated, and higher doses of oral iron, for example, 60 mg ferrous iron or even more should be recommended, according to the present iron status situation in the specific populations of women of fertile age and pregnant women.

  10. Iron and iron derived radicals

    International Nuclear Information System (INIS)

    Borg, D.C.; Schaich, K.M.

    1987-04-01

    We have discussed some reactions of iron and iron-derived oxygen radicals that may be important in the production or treatment of tissue injury. Our conclusions challenge, to some extent, the usual lines of thought in this field of research. Insofar as they are born out by subsequent developments, the lessons they teach are two: Think fast! Think small! In other words, think of the many fast reactions that can rapidly alter the production and fate of highly reactive intermediates, and when considering the impact of competitive reactions on such species, think how they affect the microenvironment (on the molecular scale) ''seen'' by each reactive molecule. 21 refs., 3 figs., 1 tab

  11. Reverse survival method of fertility estimation: An evaluation

    Directory of Open Access Journals (Sweden)

    Thomas Spoorenberg

    2014-07-01

    Full Text Available Background: For the most part, demographers have relied on the ever-growing body of sample surveys collecting full birth history to derive total fertility estimates in less statistically developed countries. Yet alternative methods of fertility estimation can return very consistent total fertility estimates by using only basic demographic information. Objective: This paper evaluates the consistency and sensitivity of the reverse survival method -- a fertility estimation method based on population data by age and sex collected in one census or a single-round survey. Methods: A simulated population was first projected over 15 years using a set of fertility and mortality age and sex patterns. The projected population was then reverse survived using the Excel template FE_reverse_4.xlsx, provided with Timæus and Moultrie (2012. Reverse survival fertility estimates were then compared for consistency to the total fertility rates used to project the population. The sensitivity was assessed by introducing a series of distortions in the projection of the population and comparing the difference implied in the resulting fertility estimates. Results: The reverse survival method produces total fertility estimates that are very consistent and hardly affected by erroneous assumptions on the age distribution of fertility or by the use of incorrect mortality levels, trends, and age patterns. The quality of the age and sex population data that is 'reverse survived' determines the consistency of the estimates. The contribution of the method for the estimation of past and present trends in total fertility is illustrated through its application to the population data of five countries characterized by distinct fertility levels and data quality issues. Conclusions: Notwithstanding its simplicity, the reverse survival method of fertility estimation has seldom been applied. The method can be applied to a large body of existing and easily available population data

  12. Playing the Fertility Game at Work

    DEFF Research Database (Denmark)

    Ciliberto, Federico; Miller, Amalia Rebecca; Nielsen, Helena Skyt

    2016-01-01

    . Allowing for heterogeneous effects by worker type, we find that positive effects dominate across worker types defined by age or education. Negative effects dominate within age groups and among low-education types. Policy simulations show that these estimated effects make the distribution of where women...... work an important consideration, beyond simply if they work, in predicting population fertility....

  13. Geohydrology and numerical simulation of ground-water flow in the central Virgin River basin of Iron and Washington Countries, Utah

    Science.gov (United States)

    Heilweil, V.M.; Freethey, G.W.; Wilkowske, C.D.; Stolp, B.J.; Wilberg, D.E.

    2000-01-01

    Because rapid growth of communities in Washington and Iron Counties, Utah, is expected to cause an increase in the future demand for water resources, a hydrologic investigation was done to better understand ground-water resources within the central Virgin River basin. This study focused on two of the principal ground-water reservoirs within the basin: the upper Ash Creek basin ground-water system and the Navajo and Kayenta aquifer system. The ground-water system of the upper Ash Creek drainage basin consists of three aquifers: the uppermost Quaternary basin-fill aquifer, the Tertiary alluvial-fan aquifer, and the Tertiary Pine Valley monzonite aquifer. These aquifers are naturally bounded by the Hurricane Fault and by drainage divides. On the basis of measurements, estimates, and numerical simulations of reasonable values for all inflow and outflow components, total water moving through the upper Ash Creek drainage basin ground-water system is estimated to be about 14,000 acre-feet per year. Recharge to the upper Ash Creek drainage basin ground-water system is mostly from infiltration of precipitation and seepage from ephemeral and perennial streams. The primary source of discharge is assumed to be evapotranspiration; however, subsurface discharge near Ash Creek Reservoir also may be important. The character of two of the hydrologic boundaries of the upper Ash Creek drainage basin ground-water system is speculative. The eastern boundary provided by the Hurricane Fault is assumed to be a no-flow boundary, and a substantial part of the ground-water discharge from the system is assumed to be subsurface outflow beneath Ash Creek Reservoir along the southern boundary. However, these assumptions might be incorrect because alternative numerical simulations that used different boundary conditions also proved to be feasible. The hydrogeologic character of the aquifers is uncertain because of limited data. Difference in well yield indicate that there is considerable

  14. Perchlorate in Fertilizers

    National Research Council Canada - National Science Library

    Eldridge, J. E; Tsui, D. T; Mattie, D. R; Crown, J; Scott, R; Blackman, T

    1999-01-01

    ...) methods for perchlorate analysis in lawn and garden fertilizers. Seven government, private, and commercial laboratories participated in the analysis of 34 aqueous suspensions of the test materials, using similar ion chromatography systems...

  15. Commercial Phosporus Fertilizer Purchased

    Data.gov (United States)

    U.S. Environmental Protection Agency — Amounts of fertilizer P2O5 purchased by states in individual years 2003, 2005, 2007, 2009 and 2011, and the % change in average amounts purchased per year from...

  16. Commercial Nitrogen Fertilizer Purchased

    Data.gov (United States)

    U.S. Environmental Protection Agency — Amounts of fertilizer nitrogen (N) purchased by states in individual years 2003, 2005, 2007, 2009 and 2011, and the % change in average amounts purchased per year...

  17. Cancer and fertility preservation

    DEFF Research Database (Denmark)

    Lambertini, Matteo; Del Mastro, Lucia; Pescio, Maria C

    2016-01-01

    In the last years, thanks to the improvement in the prognosis of cancer patients, a growing attention has been given to the fertility issues. International guidelines on fertility preservation in cancer patients recommend that physicians discuss, as early as possible, with all patients...... of reproductive age their risk of infertility from the disease and/or treatment and their interest in having children after cancer, and help with informed fertility preservation decisions. As recommended by the American Society of Clinical Oncology and the European Society for Medical Oncology, sperm...... data have become available, and several issues in this field are still controversial and should be addressed by both patients and their treating physicians.In April 2015, physicians with expertise in the field of fertility preservation in cancer patients from several European countries were invited...

  18. Queering the fertility clinic.

    Science.gov (United States)

    Mamo, Laura

    2013-06-01

    A sociologist examines contemporary engagements of queer bodies and identities with fertility biomedicine. Drawing on social science, media culture, and the author's own empirical research, three questions frame the analysis: 1. In what ways have queers on the gendered margins moved into the center and become implicated or central users of biomedicine's fertility offerings? 2. In what ways is Fertility Inc. transformed by its own incorporation of various gendered and queered bodies and identities? And 3. What are the biosocial and bioethical implications of expanded queer engagements and possibilities with Fertility Inc.? The author argues that "patient" activism through web 2.0 coupled with a largely unregulated free-market of assisted reproduction has included various queer identities as "parents-in-waiting." Such inclusions raise a set of ethical tensions regarding how to be accountable to the many people implicated in this supply and demand industry.

  19. Sperm preparation for fertilization

    NARCIS (Netherlands)

    Gadella, B.M.

    2014-01-01

    Description This book contains 19 chapters that discuss theoretical and applied andrology for domestic, zoo and wild animals. Topics include semen and its constituents; sperm production and harvest; determinants of sperm morphology; sperm preparation for fertilization; practical aspects of semen

  20. Fertilization in Flowering Plants

    Indian Academy of Sciences (India)

    Ecology and the. Environment ... agents (pollinators), the next step before fertilization is to se- .... the embryo sac are referred to as pollen-pistil interaction and play ..... evolutionary success of flowering plants when compared to other groups of ...

  1. Immunosuppressive drugs and fertility

    OpenAIRE

    Leroy, Clara; Rigot, Jean-Marc; Leroy, Maryse; Decanter, Christine; Le Mapihan, Kristell; Parent, Anne-Sophie; Le Guillou, Anne-Claire; Yakoub-Agha, Ibrahim; Dharancy, Sébastien; Noel, Christian; Vantyghem, Marie-Christine

    2015-01-01

    Immunosuppressive drugs are used in the treatment of inflammatory and autoimmune diseases, as well as in transplantation. Frequently prescribed in young people, these treatments may have deleterious effects on fertility, pregnancy outcomes and the unborn child. This review aims to summarize the main gonadal side effects of immunosuppressants, to detail the effects on fertility and pregnancy of each class of drug, and to provide recommendations on the management of patients who are seen prior ...

  2. Organic Biochar Based Fertilization

    Science.gov (United States)

    Schmidt, Hans-Peter; Pandit, Bishnu Hari; Cornelissen, Gerard; Kammann, Claudia

    2017-04-01

    Biochar produced in cost-efficient flame curtain kilns (Kon-Tiki) was nutrient enriched either with cow urine or with dissolved mineral (NPK) fertilizer to produce biochar-based fertilizers containing between 60-100 kg N, 5-60 kg P2O5 and 60-100 kg K2O, respectively, per ton of biochar. In 21 field trials nutrient-enriched biochars were applied at rates of 0.5 to 2 t ha-1 into the root zone of 13 different annual and perennial crops. Treatments combining biochar, compost and organic or chemical fertilizer were evaluated; control treatments contained the same amounts of nutrients but without biochar. All nutrient-enriched biochar substrates improved yields compared to their respective no-biochar controls. Biochar enriched with dissolved NPK produced on average 20% ± 5.1% (N=4) higher yields than standard NPK fertilization without biochar. Cow urine-enriched biochar blended with compost resulted on average in 123% ± 76.7% (N=13) higher yields compared to the organic farmer practice with cow urine-blended compost and outcompeted NPK-enriched biochar (same nutrient dose) by 103% ± 12.4% (N=4) on average. 21 field trials robustly revealed that low-dosage root zone application of organic biochar-based fertilizers caused substantial yield increases in rather fertile silt loam soils compared to traditional organic fertilization and to mineral NPK- or NPK-biochar fertilization. This can likely be explained by the nutrient carrier effect of biochar causing a slow nutrient release behavior, more balanced nutrient fluxes and reduced nutrient losses especially when liquid organic nutrients are used for the biochar enrichment. The results promise new pathways for optimizing organic farming and improving on-farm nutrient cycling.

  3. In vitro evaluation of iron solubility and dialyzability of various iron fortificants and of iron-fortified milk products targeted for infants and toddlers.

    Science.gov (United States)

    Kapsokefalou, Maria; Alexandropoulou, Isidora; Komaitis, Michail; Politis, Ioannis

    2005-06-01

    The objectives of the present study were: to compare the solubility and dialyzability of various iron fortificants (iron pyrophosphate, ferrous bis-glycinate, ferrous gluconate, ferrous lactate, ferrous sulfate) added, in the presence of ascorbic acid, to pasteurized milk samples produced under laboratory conditions; and to compare the solubility and dialyzability of iron in commercial pasteurized, UHT and condensed milk products available in the Greek market fortified with various vitamins and minerals including iron and targeted towards infants (6-12 months old) and toddlers. Iron solubility and dialyzability were determined using a simulated gastrointestinal digestive system. Ferrous dialyzable iron (molecular weight lower than 8000) was used as an index for prediction of iron bioavailability. Ferrous dialyzable iron in pasteurized milk samples fortified with iron pyrophosphate, ferrous lactate and ferrous bis-glycinate was higher (P iron in products fortified with ferrous lactate was not different (P > 0.05) from those fortified with ferrous sulfate. Ferrous dialyzable iron in four condensed commercial milk products was higher (P iron was higher (P iron source, milk processing and the overall product composition affect formation of ferrous dialyzable iron and may determine the success and effectiveness of iron fortification of milk.

  4. Iron and stony-iron meteorites

    DEFF Research Database (Denmark)

    Ruzicka, Alex M.; Haack, Henning; Chabot, Nancy L.

    2017-01-01

    By far most of the melted and differentiated planetesimals that have been sampled as meteorites are metal-rich iron meteorites or stony iron meteorites. The parent asteroids of these meteorites accreted early and differentiated shortly after the solar system formed, producing some of the oldest...... and interpretations for iron and stony iron meteorites (Plate 13.1). Such meteorites provide important constraints on the nature of metal-silicate separation and mixing in planetesimals undergoing partial to complete differentiation. They include iron meteorites that formed by the solidification of cores...... (fractionally crystallized irons), irons in which partly molten metal and silicates of diverse types were mixed together (silicate-bearing irons), stony irons in which partly molten metal and olivine from cores and mantles were mixed together (pallasites), and stony irons in which partly molten metal...

  5. Prediction of bull fertility.

    Science.gov (United States)

    Utt, Matthew D

    2016-06-01

    Prediction of male fertility is an often sought-after endeavor for many species of domestic animals. This review will primarily focus on providing some examples of dependent and independent variables to stimulate thought about the approach and methodology of identifying the most appropriate of those variables to predict bull (bovine) fertility. Although the list of variables will continue to grow with advancements in science, the principles behind making predictions will likely not change significantly. The basic principle of prediction requires identifying a dependent variable that is an estimate of fertility and an independent variable or variables that may be useful in predicting the fertility estimate. Fertility estimates vary in which parts of the process leading to conception that they infer about and the amount of variation that influences the estimate and the uncertainty thereof. The list of potential independent variables can be divided into competence of sperm based on their performance in bioassays or direct measurement of sperm attributes. A good prediction will use a sample population of bulls that is representative of the population to which an inference will be made. Both dependent and independent variables should have a dynamic range in their values. Careful selection of independent variables includes reasonable measurement repeatability and minimal correlation among variables. Proper estimation and having an appreciation of the degree of uncertainty of dependent and independent variables are crucial for using predictions to make decisions regarding bull fertility. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Conference considers low fertility.

    Science.gov (United States)

    1997-01-01

    At present, at least 51 countries--representing 44% of the world's population--are showing below-replacement fertility rates. In some of these countries, where the number of new births is not adequate to replace aging populations, this trend is problematic. In other countries, most notably China, declining fertility has conferred significant benefits. At an Economic and Social Commission for Asia and the Pacific (ESCAP) Population Commission meeting held in New York in 1997, staff from China's State Statistical Bureau reported the country has a current total fertility rate of 1.8. The birth rate remains high, however, because of the large numbers of Chinese women in the 15-49 year reproductive age group (336 million in 1997). Also buffering the impact of a low fertility rate is a large labor surplus (130 million excess workers in rural China). To keep fertility below the replacement level, China plans to improve the quality of its family planning service, enhance poverty alleviation programs, and increase incentives for small families in rural areas. China's low fertility rate has provided an important impetus for economic development.

  7. Effect of surfactant-coated iron oxide nanoparticles on the effluent water quality from a simulated sequencing batch reactor treating domestic wastewater

    International Nuclear Information System (INIS)

    Hwang, Sangchul; Martinez, Diana; Perez, Priscilla; Rinaldi, Carlos

    2011-01-01

    This study was conducted to evaluate the effect of commercially available engineered iron oxide nanoparticles coated with a surfactant (ENP Fe-surf ) on effluent water quality from a lab-scale sequencing batch reactor as a model secondary biological wastewater treatment. Results showed that ∼8.7% of ENP Fe-surf applied were present in the effluent stream. The stable presence of ENP Fe-surf was confirmed by analyzing the mean particle diameter and iron concentration in the effluent. Consequently, aqueous ENP Fe-surf deteriorated the effluent water quality at a statistically significant level (p Fe-surf would be introduced into environmental receptors through the treated effluent and could potentially impact them. - Highlights: → Surfactant-coated engineered iron oxide nanoparticles (ENP Fe-surf ) were assessed. → Effluent quality was analyzed from a sequencing batch reactor with ENP Fe-surf . → ∼8.7% of ENP Fe-surf applied was present in the effluent. → ENP Fe-surf significantly (p Fe-surf will be introduced into environmental receptors. - Stable presence of surfactant-coated engineered iron oxides nanoparticles deteriorated the effluent water quality at a statistically significant level (p < 0.05).

  8. Synthesis, iron(III) complexation properties, molecular dynamics simulations and P. aeruginosa siderophore-like activity of two pyoverdine analogs.

    Science.gov (United States)

    Antonietti, Viviane; Boudesocque, Stéphanie; Dupont, Laurent; Farvacques, Natacha; Cézard, Christine; Da Nascimento, Sophie; Raimbert, Jean-François; Socrier, Larissa; Robin, Thierry-Johann; Morandat, Sandrine; El Kirat, Karim; Mullié, Catherine; Sonnet, Pascal

    2017-09-08

    P. aeruginosa ranks among the top five organisms causing nosocomial infections. Among the many novel strategies for developing new therapeutics against infection, targeting iron uptake mechanism seems promising as P. aeruginosa needs iron for its growth and survival. To scavenge iron, the bacterium produces siderophores possessing a very high affinity towards Fe(III) ions such as pyoverdines. In this work, we decided to study two pyoverdine analogs, aPvd2 and aPvd3, structurally close to the endogen pyoverdine. The pFe constants calculated with the values of formation showed a high affinity of aPvd3 towards Fe(III). Molecular dynamics calculations demonstrated that aPvd3-Fe forms with Fe(III) stable 1:1 complexes in water, whereas aPvd2 does not. Only aPvd3 is able to increase the bacterial growth and represents thus an alternative to pyoverdine for iron acquisition by the bacterium. The aPvd2-3 interaction studies with a lipid membrane indicated that they were unable to interact and to cross the plasma membrane of bacteria by passive diffusion. Consequently, the penetration of aPvd3 is ruled by a transport membrane protein. These results showed that aPvd3 may be used to inhibit pyoverdine uptake or to promote the accumulation and release of antibiotics into the cell following a Trojan horse strategy. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  9. Short-Term Success versus Long-Term Failure: A Simulation-Based Approach for Understanding the Potential of Zambia’s Fertilizer Subsidy Program in Enhancing Maize Availability

    Directory of Open Access Journals (Sweden)

    Andreas Gerber

    2016-10-01

    Full Text Available In Sub-Saharan Africa, food-related policies such as fertilizer subsidy programs (FSPs have undergone a revival and triggered a controversy about their impact. In this article I applied a simulation-based approach to examine the FSPs’ short- and long-term potential for increasing maize availability in Zambia. The study revealed that FSPs are an effective policy measure to enhance maize availability in the short-term. However, in the long-term, the food system becomes dependent on the government’s annual expenses. The dependency occurs because FSPs fail to build up adequate stock levels of soil organic matter (SOM, which is an important source of resilience and productivity, and thus represents a long-term leverage point in Zambia’s maize production system. For this reason, alternative policies that combine increasing productivity and building up SOM stock levels were analyzed. They were found to be a viable means for enhancing long-term maize availability. The study concludes that gradually reducing investments in FSPs while simultaneously promoting farming practices that build up SOM stock levels is a promising strategy to enhance maize availability sustainably.

  10. Effects of Long-term Fertilization on Potassium Fixation Capacity in Brown Soil

    Science.gov (United States)

    Li, Na; Guo, Chunlei; Wang, Yue; Gao, Tianyi; Yang, Jinfeng; Han, Xiaori

    2018-01-01

    This study concentrated on the research of features of fixation. The objective of this study was to provide theoretical foundation of rational application of potassium fertilizer along with improving fertilizer availability ratio. A 32 years long-term experiment was conducted to evaluate the effects of fertilizer application on potassium changes and the factors affecting K fixation on brown soil by simulation in laboratory. When the concentration of exogenous potassium was in range of 400∼4000 mg·kg-1, potassium fixation capacity increased along with the rise of concentration of exogenous potassium, whereas K fixation rate reduced; Compared with no-potassium fertilizer, application of potassium fertilizer and organic fertilizer reduced soil potassium fixation capacity. Potassium rate and fixation-release of potassium character in soil should be taken into comprehensive consideration for rational fertilization to maintain or improve soil fertility for increasing potassium fertilizers efficiency in agriculture.

  11. Ocean carbon sequestration by fertilization: An integrated bioeochemical assessment

    Energy Technology Data Exchange (ETDEWEB)

    Gruber, N.; Sarmiento, J.L.; Gnandesikan, A.

    2005-05-31

    Under this grant, the authors investigated a range of issues associated with the proposal to fertilize the ocean with nutrients (such as iron) in order to increase the export of organic matter from the ocean's near surface waters and consequently increase the uptake of CO{sub 2} from the atmosphere. There are several critical scientific questions that have the potential to be make-or-break issues for this proposed carbon sequestration mechanism: (1) If iron is added to the ocean, will export of organic carbon from the surface actually occur? Clearly, if no export occurs, then there will be no sequestration. (2) if iron fertilization does lead to export of organic carbon from the surface of the ocean, how much CO{sub 2} will actually be removed from the atmosphere? Even if carbon is removed from the surface of the ocean, this does not guarantee that there will be significant removal of CO{sub 2} from the atmosphere, since the CO{sub 2} may be supplied by a realignment of dissolved inorganic carbon within the ocean. (3) What is the time scale of any sequestration that occurs? If sequestered CO{sub 2} returns to the atmosphere on a relatively short time scale, iron fertilization will not contribute significantly to slowing the growth of atmospheric CO{sub 2}. (4) Can the magnitude of sequestration be verified? If verification is extremely difficult or impossible, this option is likely to be viewed less favorably. (5) What unintended consequences might there be from fertilizing the ocean with iron? If these are severe enough, they will be a significant impact on policy decisions. Most research on carbon sequestration by fertilization has focused on the first of these issues. Although a number of in situ fertilization experiments have successfully demonstrated that the addition of iron leads to a dramatic increase in ocean productivity, the question of whether this results in enhanced export remains an open one. The primary focus of the research was on the

  12. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español Iron-deficiency anemia is a ... address the cause of your iron deficiency, such as any underlying bleeding. If undiagnosed or untreated, iron- ...

  13. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español Iron-deficiency ... anemia. Blood tests to screen for iron-deficiency anemia To screen for iron-deficiency anemia, your doctor ...

  14. Iron-Deficiency Anemia

    Science.gov (United States)

    ... To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español Iron-deficiency ... anemia. Blood tests to screen for iron-deficiency anemia To screen for iron-deficiency anemia, your doctor ...

  15. Radioactivity in Chemical Fertilizers

    International Nuclear Information System (INIS)

    Jankovic, M.; Nikolic, J.; Pantelic, G.; Rajacic, M.; Sarap, N.; Todorovic, D.

    2013-01-01

    The fertilizers are essential in agriculture as they supply nutrients to the farming fields. One of the sources of radioactivity other than those of natural origin is mainly due to extensive use of fertilizers. The concentrations of natural radionuclides, 40K, 226Ra, 238U and 235U in different chemical fertilizers, which are part of the regular control of imported goods from the border crossing were analyzed using gamma spectrometry with a high purity germanium (HPGe) detector, relative efficiency 20 %, in order to assess the implications of the extended use of chemical fertilizers. Measurements were performed at Vinca Institute, Radiation and Environmental Protection Department. The obtained results show remarkable wide variations in the radioactivity contents of different samples. The mean (ranges) of specific activities for gamma activity of those fertilizer samples for 40K, 226Ra, 238U and 235U are 4857 (23 - 12 324) Bq/kg, 87 (4-393) Bq/kg, 220 (26-1145) Bq/kg and 15 (1.6-53) Bq/kg, respectively. The radium equivalent activity (Ra eq ) as well as the external absorbed gamma dose rate (D) for all samples was also calculated.(author)

  16. Medication adherence to oral iron therapy in patients with iron deficiency anemia

    Science.gov (United States)

    Gereklioglu, Cigdem; Asma, Suheyl; Korur, Asli; Erdogan, Ferit; Kut, Altug

    2016-01-01

    Objective: This study aimed at investigating the factors affecting medication adherence in patients who use oral iron therapy due to iron deficiency anemia. Methods: A total of 96 female patients in fertile age with mean age of 30±10.1 years (range 18-53) who were admitted to Family Medicine Clinic between 01 January and 31 March 2015 and who had received iron therapy within the recent three years were enrolled in the study. Data were collected through a questionnaire form. Results: Of the patients, 39 (40,6%) were detected not to use the medication regularly or during the recommended period. A statistically significant relationship was found between non-adherence to therapy and gastrointestinal side effects and weight gain (p<0.05). Conclusion: Medication adherence is deficient in patients with iron deficiency anemia. The most important reason for this seems gastrointestinal side effects, in addition to weight gain under treatment. PMID:27375698

  17. Medication adherence to oral iron therapy in patients with iron deficiency anemia.

    Science.gov (United States)

    Gereklioglu, Cigdem; Asma, Suheyl; Korur, Asli; Erdogan, Ferit; Kut, Altug

    2016-01-01

    This study aimed at investigating the factors affecting medication adherence in patients who use oral iron therapy due to iron deficiency anemia. A total of 96 female patients in fertile age with mean age of 30±10.1 years (range 18-53) who were admitted to Family Medicine Clinic between 01 January and 31 March 2015 and who had received iron therapy within the recent three years were enrolled in the study. Data were collected through a questionnaire form. Of the patients, 39 (40,6%) were detected not to use the medication regularly or during the recommended period. A statistically significant relationship was found between non-adherence to therapy and gastrointestinal side effects and weight gain (p<0.05). Medication adherence is deficient in patients with iron deficiency anemia. The most important reason for this seems gastrointestinal side effects, in addition to weight gain under treatment.

  18. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... making new blood cells. Visit our Aplastic Anemia Health Topic to learn more. ... recommend that you take iron supplements, also called iron pills or oral iron, by mouth once or several times a ...

  19. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... red meat, salmon, iron-fortified breads and cereals, peas, tofu, dried fruits, and dark green leafy vegetables. ... stored iron has been used. Ferritin is a protein that helps store iron in your body. Reticulocyte ...

  20. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... drinking black tea, which reduces iron absorption. Other treatments If you have chronic kidney disease and iron- ... and lifestyle changes to avoid complications. Follow your treatment plan Do not stop taking your prescribed iron ...

  1. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... diagnoses you with iron-deficiency anemia, your treatment will depend on the cause and severity of the ... of iron. The recommended daily amounts of iron will depend on your age, sex, and whether you ...

  2. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... heart failure . Increased risk of infections Motor or cognitive development delays in children Pregnancy complications, such as ... iron-deficiency anemia may require intravenous (IV) iron therapy or a blood transfusion . Iron supplements Your doctor ...

  3. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... for iron-deficiency anemia. Lifestyle habits Certain lifestyle habits may increase your risk for iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, such ...

  4. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... because your body’s intake of iron is too low. Low intake of iron can happen because of blood ... delivery or giving birth to a baby with low birth weight In people with chronic conditions, iron- ...

  5. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... breastfeeding. Recommended daily iron intake for children and adults. The table lists the recommended amounts of iron, ... increased need for iron during growth spurts. Older adults, especially those over age 65. Unhealthy environments Children ...

  6. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... girls. From birth to 6 months, babies need 0.27 mg of iron. This number goes up ... screen blood donors for low iron stores. Reliable point-of-care testing may help identify iron deficiency ...

  7. Iron metabolism and toxicity

    International Nuclear Information System (INIS)

    Papanikolaou, G.; Pantopoulos, K.

    2005-01-01

    Iron is an essential nutrient with limited bioavailability. When present in excess, iron poses a threat to cells and tissues, and therefore iron homeostasis has to be tightly controlled. Iron's toxicity is largely based on its ability to catalyze the generation of radicals, which attack and damage cellular macromolecules and promote cell death and tissue injury. This is lucidly illustrated in diseases of iron overload, such as hereditary hemochromatosis or transfusional siderosis, where excessive iron accumulation results in tissue damage and organ failure. Pathological iron accumulation in the liver has also been linked to the development of hepatocellular cancer. Here we provide a background on the biology and toxicity of iron and the basic concepts of iron homeostasis at the cellular and systemic level. In addition, we provide an overview of the various disorders of iron overload, which are directly linked to iron's toxicity. Finally, we discuss the potential role of iron in malignant transformation and cancer

  8. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... amount of iron, and medical conditions that make it hard for your body to absorb iron from ... hepcidin. Hepcidin prevents iron from leaving cells where it is stored or from being absorbed in the ...

  9. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... bleeding. If undiagnosed or untreated, iron-deficiency anemia can cause serious complications, including heart failure and development ... iron is too low. Low intake of iron can happen because of blood loss, consuming less than ...

  10. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... iron-fortified foods that have iron added. Vegetarian diets can provide enough iron if you choose nonmeat ... Anemia in Chronic Kidney Disease (National Institute of Diabetes and Digestive and Kidney Diseases) Avoiding Anemia (National ...

  11. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... lean red meat, salmon, iron-fortified breads and cereals, peas, tofu, dried fruits, and dark green leafy ... sources of iron, including iron-fortified breads and cereals, beans, tofu, dried fruits, and spinach and other ...

  12. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... starch. Restless legs syndrome Shortness of breath Weakness Complications Undiagnosed or untreated iron-deficiency anemia may cause ... as complete blood count and iron studies. Prevent complications over your lifetime To prevent complications from iron- ...

  13. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... you do not have enough iron in your body. People with mild or moderate iron-deficiency anemia ... and where to find more information. Causes Your body needs iron to make healthy red blood cells. ...

  14. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... from developing iron-deficiency anemia. Foods that are good sources of iron include dried beans, dried fruits, eggs, lean red meat, ... signs of iron-deficiency anemia include: Brittle nails ...

  15. Taking iron supplements

    Science.gov (United States)

    ... medlineplus.gov/ency/article/007478.htm Taking iron supplements To use the sharing features on this page, ... levels. You may also need to take iron supplements as well to rebuild iron stores in your ...

  16. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... fruits, eggs, lean red meat, salmon, iron-fortified breads and cereals, peas, tofu, dried fruits, and dark ... choose nonmeat sources of iron, including iron-fortified breads and cereals, beans, tofu, dried fruits, and spinach ...

  17. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... ESAs are usually used with iron therapy or IV iron, or when iron therapy alone is not enough. Look for Living With will discuss what your doctor may recommend, including lifelong lifestyle changes ...

  18. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... and pregnancy. Good sources of iron are meat, poultry, fish, and iron-fortified foods that have iron ... Anemia Restless Legs Syndrome Von Willebrand Disease Other Resources NHLBI resources Your Guide to Anemia [PDF, 1. ...

  19. Fertility outcomes in asthma

    DEFF Research Database (Denmark)

    Gade, Elisabeth Juul; Thomsen, Simon Francis; Lindenberg, Svend

    2016-01-01

    Evidence is increasing of an association between asthma and aspects of female reproduction. However, current knowledge is limited and furthermore relies on questionnaire studies or small populations. In a prospective observational cohort study to investigate whether time to pregnancy, the number...... of fertility treatments, and the number of successful pregnancies differ significantly between women with unexplained infertility with and without asthma.245 women with unexplained infertility (aged 23-45 years) underwent questionnaires and asthma and allergy testing while undergoing fertility treatment. 96...... women entering the study had either a former doctor's diagnosis of asthma or were diagnosed with asthma when included. After inclusion they were followed for a minimum of 12 months in fertility treatment, until they had a successful pregnancy, stopped treatment, or the observation ended.The likelihood...

  20. The fertilizer nitrogen problem

    Energy Technology Data Exchange (ETDEWEB)

    Olson, R A; Halstead, E H

    1974-07-01

    A world-wide fossil fuel crisis has surfaced in the past year by reason of shortage and high cost, which is felt throughout all segments of human society. Nor has the agriculture sector, with its very high demand for energy to supply its power, machinery, fertilizer, processing and transport, escaped the energy crisis. Among the agricultural inputs, fertilizer nitrogen is one of major concern. This commodity is currently in extremely short supply, world prices having more than doubled in the past year alone. Serious as this situation is to agricultural production in the highly developed countries of the world, it is a real disaster to the production potential of the developing countries. The birth of the 'Green Revolution' in those countries in the last ten years came about from an amalgamation of higher yielding varieties, improved pest and disease control, better crop watering practices, and the introduction of fertilizer nitrogen. Shortcomings in any one of these requisites invalidates the entire package. (author)

  1. The fertilizer nitrogen problem

    International Nuclear Information System (INIS)

    Olson, R.A.; Halstead, E.H.

    1974-01-01

    A world-wide fossil fuel crisis has surfaced in the past year by reason of shortage and high cost, which is felt throughout all segments of human society. Nor has the agriculture sector, with its very high demand for energy to supply its power, machinery, fertilizer, processing and transport, escaped the energy crisis. Among the agricultural inputs, fertilizer nitrogen is one of major concern. This commodity is currently in extremely short supply, world prices having more than doubled in the past year alone. Serious as this situation is to agricultural production in the highly developed countries of the world, it is a real disaster to the production potential of the developing countries. The birth of the 'Green Revolution' in those countries in the last ten years came about from an amalgamation of higher yielding varieties, improved pest and disease control, better crop watering practices, and the introduction of fertilizer nitrogen. Shortcomings in any one of these requisites invalidates the entire package. (author)

  2. Simulation

    DEFF Research Database (Denmark)

    Gould, Derek A; Chalmers, Nicholas; Johnson, Sheena J

    2012-01-01

    Recognition of the many limitations of traditional apprenticeship training is driving new approaches to learning medical procedural skills. Among simulation technologies and methods available today, computer-based systems are topical and bring the benefits of automated, repeatable, and reliable p...... performance assessments. Human factors research is central to simulator model development that is relevant to real-world imaging-guided interventional tasks and to the credentialing programs in which it would be used....

  3. Fertility and the economy.

    Science.gov (United States)

    Becker, G S

    1992-08-01

    Fertility and the economy is examined in the context of the Malthusian question about the links between family choices and longterm economic growth. Micro level differences are not included not are a comprehensive range of economic or determinant variables. Specific attention is paid to income and price effects, the quality of children, overlapping generations, mortality effects, uncertainty, and economic growth. Fertility and the demand for children in linked to parental incomes and the cost of rearing children, which is affected by public policies that change the costs. Demand is also related to child and adult mortality, and uncertainty about sex of the child. Fertility in one generation affects fertility in the next. Malthusian and neoclassical models do not capture the current model of modern economies with rising income/capita and human and physical capital, extensive involvement of married women in the labor force, and declining fertility to very low levels. In spite of the present advances in firm knowledge about the relationships between fertility and economic and social variables, there is still much greater ignorance of the interactions. The Malthusian utility function that says fertility rises and falls with income did hold up to 2 centuries of scrutiny, and the Malthusian inclusion of the shifting tastes in his analysis could be translated in the modern context to include price of children. The inclusion of net cost has significant consequences, i.e., rural fertility can be higher because the cost of rearing when children contribute work to maintaining the farm is lower than in the city. An income tax deduction for children in the US reduces cost. Economic growth raises the cost of children due the time spent on child care becoming more valuable. The modern context has changed from Malthusian time, and the cost of education, training, and medical care is relevant. The implication is that a rise in income could reduce the demand for children when

  4. Genetics Home Reference: iron-refractory iron deficiency anemia

    Science.gov (United States)

    ... refractory iron deficiency anemia Iron-refractory iron deficiency anemia Printable PDF Open All Close All Enable Javascript ... expand/collapse boxes. Description Iron-refractory iron deficiency anemia is one of many types of anemia , which ...

  5. Cast iron - a predictable material

    Directory of Open Access Journals (Sweden)

    Jorg C. Sturm

    2011-02-01

    Full Text Available High strength compacted graphite iron (CGI or alloyed cast iron components are substituting previously used non-ferrous castings in automotive power train applications. The mechanical engineering industry has recognized the value in substituting forged or welded structures with stiff and light-weight cast iron castings. New products such as wind turbines have opened new markets for an entire suite of highly reliable ductile iron cast components. During the last 20 years, casting process simulation has developed from predicting hot spots and solidification to an integral assessment tool for foundries for the entire manufacturing route of castings. The support of the feeding related layout of the casting is still one of the most important duties for casting process simulation. Depending on the alloy poured, different feeding behaviors and self-feeding capabilities need to be considered to provide a defect free casting. Therefore, it is not enough to base the prediction of shrinkage defects solely on hot spots derived from temperature fields. To be able to quantitatively predict these defects, solidification simulation had to be combined with density and mass transport calculations, in order to evaluate the impact of the solidification morphology on the feeding behavior as well as to consider alloy dependent feeding ranges. For cast iron foundries, the use of casting process simulation has become an important instrument to predict the robustness and reliability of their processes, especially since the influence of alloying elements, melting practice and metallurgy need to be considered to quantify the special shrinkage and solidification behavior of cast iron. This allows the prediction of local structures, phases and ultimately the local mechanical properties of cast irons, to asses casting quality in the foundry but also to make use of this quantitative information during design of the casting. Casting quality issues related to thermally driven

  6. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... increased need for iron during growth spurts. Older adults, especially those over age ... athletes. Athletes, especially young females, are at risk for iron deficiency. Endurance ...

  7. Iron and stony-iron meteorites

    DEFF Research Database (Denmark)

    Benedix, Gretchen K.; Haack, Henning; McCoy, T. J.

    2014-01-01

    Without iron and stony-iron meteorites, our chances of ever sampling the deep interior of a differentiated planetary object would be next to nil. Although we live on a planet with a very substantial core, we will never be able to sample it. Fortunately, asteroid collisions provide us with a rich...... sampling of the deep interiors of differentiated asteroids. Iron and stony-iron meteorites are fragments of a large number of asteroids that underwent significant geological processing in the early solar system. Parent bodies of iron and some stony-iron meteorites completed a geological evolution similar...... to that continuing on Earth – although on much smaller length- and timescales – with melting of the metal and silicates; differentiation into core, mantle, and crust; and probably extensive volcanism. Iron and stony-iron meteorites are our only available analogues to materials found in the deep interiors of Earth...

  8. Globalization and Contemporary Fertility Convergence.

    Science.gov (United States)

    Hendi, Arun S

    2017-09-01

    The rise of the global network of nation-states has precipitated social transformations throughout the world. This article examines the role of political and economic globalization in driving fertility convergence across countries between 1965 and 2009. While past research has typically conceptualized fertility change as a country-level process, this study instead employs a theoretical and methodological framework that examines differences in fertility between pairs of countries over time. Convergence in fertility between pairs of countries is hypothesized to result from increased cross-country connectedness and cross-national transmission of fertility-related schemas. I investigate the impact of various cross-country ties, including ties through bilateral trade, intergovernmental organizations, and regional trade blocs, on fertility convergence. I find that globalization acts as a form of social interaction to produce fertility convergence. There is significant heterogeneity in the effects of different cross-country ties. In particular, trade with rich model countries, joint participation in the UN and UNESCO, and joining a free trade agreement all contribute to fertility convergence between countries. Whereas the prevailing focus in fertility research has been on factors producing fertility declines, this analysis highlights specific mechanisms-trade and connectedness through organizations-leading to greater similarity in fertility across countries. Globalization is a process that propels the spread of culturally laden goods and schemas impinging on fertility, which in turn produces fertility convergence.

  9. Iron from Zealandic bog iron ore -

    DEFF Research Database (Denmark)

    Lyngstrøm, Henriette Syrach

    2011-01-01

    og geologiske materiale, metallurgiske analyser og eksperimentel arkæologiske forsøg - konturerne af en jernproduktion med udgangspunkt i den sjællandske myremalm. The frequent application by archaeologists of Werner Christensen’s distribution map for the occurrence of bog iron ore in Denmark (1966...... are sketched of iron production based on bog iron ore from Zealand....

  10. Correlations in fertility across generations: can low fertility persist?

    Science.gov (United States)

    Kolk, Martin; Cownden, Daniel; Enquist, Magnus

    2014-01-01

    Correlations in family size across generations could have a major influence on human population size in the future. Empirical studies have shown that the associations between the fertility of parents and the fertility of children are substantial and growing over time. Despite their potential long-term consequences, intergenerational fertility correlations have largely been ignored by researchers. We present a model of the fertility transition as a cultural process acting on new lifestyles associated with fertility. Differences in parental and social influences on the acquisition of these lifestyles result in intergenerational correlations in fertility. We show different scenarios for future population size based on models that disregard intergenerational correlations in fertility, models with fertility correlations and a single lifestyle, and models with fertility correlations and multiple lifestyles. We show that intergenerational fertility correlations will result in an increase in fertility over time. However, present low-fertility levels may persist if the rapid introduction of new cultural lifestyles continues into the future. PMID:24478294

  11. Simulation

    CERN Document Server

    Ross, Sheldon

    2006-01-01

    Ross's Simulation, Fourth Edition introduces aspiring and practicing actuaries, engineers, computer scientists and others to the practical aspects of constructing computerized simulation studies to analyze and interpret real phenomena. Readers learn to apply results of these analyses to problems in a wide variety of fields to obtain effective, accurate solutions and make predictions about future outcomes. This text explains how a computer can be used to generate random numbers, and how to use these random numbers to generate the behavior of a stochastic model over time. It presents the statist

  12. Fertilizing Southern Hardwoods

    Science.gov (United States)

    W. M. Broadfoot; A. F. Ike

    1967-01-01

    If present trends continue, fertilizing may soon be economically feasible in southern hardwood stands. Demands for the wood are rising, and the acreage alloted for growing it is steadily shrinking. To supply anticipated requests for information, the U. S. Forest Service has established tree nutrition studies at the Southern Hardwoods Laboratory in Stoneville,...

  13. Hispanic Adolescent Fertility.

    Science.gov (United States)

    Darabi, Katherine F.; And Others

    1986-01-01

    Discusses fertility of Hispanic adolescents in the United States. Summarizes what is known about sexuality, contraception, pregnancy, and childbearing among male and female Hispanics of various countries of origin. Indicates Hispanic adolescent birthrates fall between those of non-Hispanic Whites and Blacks, but there is considerable within-group…

  14. Fertilizer micro-dosing

    International Development Research Centre (IDRC) Digital Library (Canada)

    Localized application of small quantities of fertilizer (micro-dosing), combined with improved planting pits for rainwater harvesting, has generated greater profits and food security for women farmers in the Sahel. • Women are 25% more likely to use combined applications, and have expanded areas of food crops (cowpea,.

  15. Fertility Treatments for Females

    Science.gov (United States)

    ... on: The underlying cause of the problem The woman's age Her history of previous pregnancies How long she has had infertility issues The presence or absence of male factor infertility Fertility treatments are most likely to benefit women whose infertility is due to problems with ovulation. ...

  16. Nutrition and fertility.

    Science.gov (United States)

    Pinelli, G; Tagliabue, A

    2007-12-01

    The first studies about fertility and nutrition date back to the 70ies and already showed a strict relation among female fertility, weight and body composition. However, the mechanisms of this connection started to be explained only after leptin's discovery. According to some authors' opinion, leptin could interact with reproductive axis at multiple sites with stimulatory effects at the hypothalamus and pituitary and stimulatory or inhibitory actions at the gonads. Leptin could play a role in other physiologic processes such as menstruation and pregnancy, and could initiate the complex process of puberty. It has been showed that conditions in which nutritional status is suboptimal, such as eating disorders, exercise induced amenhorrea, functional hypothalamic amenhorrea and polycystic ovarian syndrome, are associated with abnormal leptin levels. These conditions, are characterized by severe changes in body composition and dietary habits. Since leptin is regulated by body composition and dietary factors, (such as energy intake and macronutrient composition), a strict connection between nutritional intake and fertility regulated by leptin is confirmed. This review focuses on the current knowledge about nutritional factors that influence leptin levels. Since clinical and subclinical nutritional imbalance can determine the development and the maintenance of neuroendocrine and metabolic aberrations, studies on fertility need a deeper attention about dietary habits and nutritional status.

  17. Fertility and Infertility.

    Science.gov (United States)

    Orgebin-Crist, Marie-Claire; And Others

    In this report, emphasis is placed on major research developments in the reproductive sciences, their impact on the health of individuals as well as on that of society, and on current trends that may provide new opportunities for future research in fertility and infertility. In the first section, major developments in the reproductive sciences are…

  18. Native iron

    DEFF Research Database (Denmark)

    Brooks, Charles Kent

    2015-01-01

    System, was reduced. The oxidized outer layers of the Earth have formed by two processes. Firstly, water is decomposed to oxygen and hydrogen by solar radiation in the upper parts of the atmosphere, the light hydrogen diffusing to space, leaving oxygen behind. Secondly, plants, over the course......, hematite, or FeO.Fe2O3, magnetite), with carbon in the form of coke. This is carried out in a blast furnace. Although the Earth's core consists of metallic iron, which may also be present in parts of the mantle, this is inaccessible to us, so we must make our own. In West Greenland, however, some almost......We live in an oxidized world: oxygen makes up 22 percent of the atmosphere and by reacting with organic matter produces most of our energy, including the energy our bodies use to function: breathe, think, move, etc. It has not always been thus. Originally the Earth, in common with most of the Solar...

  19. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries ... Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. ...

  20. Sex and Fertility After SCI

    Science.gov (United States)

    ... Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries ... Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. ...

  1. Agriculture: Nutrient Management and Fertilizer

    Science.gov (United States)

    Fertilizers and soil amendments can be derived from raw materials, composts and other organic matter, and wastes, such as sewage sludge and certain industrial wastes. Overuse of fertilizers can result in contamination of surface water and groundwater.

  2. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Resources Peer Counseling Blog About Media Donate close search Understanding Spinal Cord Injury What is a Spinal ... male fertility? play_arrow Where can people get information on sex and fertility after a spinal cord ...

  3. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord ... a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. Rowles, MS, ...

  4. Foods That Can Affect Fertility

    Science.gov (United States)

    ... That Can Affect Fertility Print Email Foods That Can Affect Fertility By Caroline Kaufman, MS, RDN Published ... the American Society for Reproductive Medicine. While couples can't control all of the causes of infertility, ...

  5. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... male fertility? play_arrow Where can people get information on sex and fertility after a spinal cord ... health care products or services, or control the information found on external websites. The Hill Foundation is ...

  6. Ocean iron fertilization - Moving forward in a sea of uncertainty

    Digital Repository Service at National Institute of Oceanography (India)

    Buesseler, K.O.; Doney, S.C.; Karl, D.M.; Boyd, P.W.; Caldeira, K.; Chai, F.; Coale, K.H.; de Baar, H.J.W.; Falkowski, P.G.; Johnson, K.S.; Lampitt, R.S.; Michaels, A.F.; Naqvi, S.W.A.; Smetacek, V.; Takeda, S.; Watson, A.J.

    California, Los Angeles, CA, USA. 12National Institute of Oceanography, Goa, India. 13Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany. 14Department of Aquatic Bioscience, University of Tokyo, Tokyo, Japan. 15School...

  7. Microbial community response during the iron fertilization experiment LOHAFEX

    Digital Repository Service at National Institute of Oceanography (India)

    Thiele, S.; Fuchs, B.M.; Ramaiah, N.; Amanna, R.

    of the experiment. The globe and the inset map were generated with the M_Map package for Matlab (version 7.12.0.635; MathWorks, Natick, MA). The chlorophyll a data were downloaded from the NASA website http://oceancolor.gsfc.nasa.gov/. Thiele et al. 8804 aem...

  8. Marketing Green Fertilizers: Insights into Consumer Preferences

    OpenAIRE

    Johannes Dahlin; Verena Halbherr; Peter Kurz; Michael Nelles; Carsten Herbes

    2016-01-01

    In an effort to support the long-term viability of the bioenergy industry through an end market for digestate, we investigated purchasing preferences for fertilizer product features in the home gardening market. We conducted a discrete choice experiment (DCE), presenting 504 respondents with a total of 6048 product attribute choices in a simulated context that replicated the tradeoff decisions made in the real marketplace. We analyzed the choice data using a hierarchical Bayes estimate to gen...

  9. Socioeconomic status and fertility decline

    DEFF Research Database (Denmark)

    Dribe, Martin; Breschi, Marco; Gagnon, Alain

    2017-01-01

    America to analyse the relationship between socio-economic status and fertility during the fertility transition. Using comparable analytical models and class schemes for each population, we examined the changing socio-economic differences in marital fertility and related these to common theories...

  10. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Provider Pocket Guides Provider Guides Fertility Preservation for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed ... Patient Pocket Guides Patient Guides Fertility Preservation for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed ...

  11. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ...

  12. Fertility Preservation for Children Diagnosed with Cancer

    Science.gov (United States)

    ... Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu ... with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for ...

  13. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... blocks the intestine from taking up iron. Other medical conditions Other medical conditions that may lead to iron-deficiency anemia ... daily amount of iron. If you have other medical conditions that cause iron-deficiency anemia , such as ...

  14. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Home / < Back To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español ... bleeding Consuming less than recommended daily amounts of iron Iron-deficiency anemia can be caused by getting ...

  15. Serum iron test

    Science.gov (United States)

    Fe+2; Ferric ion; Fe++; Ferrous ion; Iron - serum; Anemia - serum iron; Hemochromatosis - serum iron ... A blood sample is needed. Iron levels are highest in the morning. Your health care provider will likely have you do this test in the morning.

  16. Nutritional iron deficiency

    NARCIS (Netherlands)

    Zimmermann, M.B.; Hurrell, R.F.

    2007-01-01

    Iron deficiency is one of the leading risk factors for disability and death worldwide, affecting an estimated 2 billion people. Nutritional iron deficiency arises when physiological requirements cannot be met by iron absorption from diet. Dietary iron bioavailability is low in populations consuming

  17. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... also are hoping to determine which iron supplements work best to treat iron-deficiency anemia in children who do not consume the daily recommended amount of iron. Read less Participate in NHLBI Clinical Trials We lead or sponsor many studies related to iron-deficiency anemia. See if you ...

  18. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... peas, tofu, dried fruits, and dark green leafy vegetables. Foods rich in vitamin C, such as oranges, strawberries, ... iron are meat, poultry, fish, and iron-fortified foods that have iron ... green leafy vegetables. You can also take an iron supplement. Follow ...

  19. Iron deficiency anemia

    Science.gov (United States)

    Anemia - iron deficiency ... iron from old red blood cells. Iron deficiency anemia develops when your body's iron stores run low. ... You may have no symptoms if the anemia is mild. Most of the time, ... slowly. Symptoms may include: Feeling weak or tired more often ...

  20. Water quality, hydrology, and simulated response to changes in phosphorus loading of Mercer Lake, Iron County, Wisconsin, with special emphasis on the effects of wastewater discharges

    Science.gov (United States)

    Robertson, Dale M.; Garn, Herbert S.; Rose, William J.; Juckem, Paul F.; Reneau, Paul C.

    2012-01-01

    Mercer Lake is a relatively shallow drainage lake in north-central Wisconsin. The area near the lake has gone through many changes over the past century, including urbanization and industrial development. To try to improve the water quality of the lake, actions have been taken, such as removal of the lumber mill and diversion of all effluent from the sewage treatment plant away from the lake; however, it is uncertain how these actions have affected water quality. Mercer Lake area residents and authorities would like to continue to try to improve the water quality of the lake; however, they would like to place their efforts in the actions that will have the most beneficial effects. To provide a better understanding of the factors affecting the water quality of Mercer Lake, a detailed study of the lake and its watershed was conducted by the U.S. Geological Survey in collaboration with the Mercer Lake Association. The purposes of the study were to describe the water quality of the lake and the composition of its sediments; quantify the sources of water and phosphorus loading to the lake, including sources associated with wastewater discharges; and evaluate the effects of past and future changes in phosphorus inputs on the water quality of the lake using eutrophication models (models that simulate changes in phosphorus and algae concentrations and water clarity in the lake). Based on analyses of sediment cores and monitoring data collected from the lake, the water quality of Mercer Lake appears to have degraded as a result of the activities in its watershed over the past 100 years. The water quality appears to have improved, however, since a sewage treatment plant was constructed in 1965 and its effluent was routed away from the lake in 1995. Since 2000, when a more consistent monitoring program began, the water quality of the lake appears to have changed very little. During the two monitoring years (MY) 2008-09, the average summer near-surface concentration of total

  1. Selection of suitable fertilizer draw solute for a novel fertilizer-drawn forward osmosis-anaerobic membrane bioreactor hybrid system.

    Science.gov (United States)

    Kim, Youngjin; Chekli, Laura; Shim, Wang-Geun; Phuntsho, Sherub; Li, Sheng; Ghaffour, Noreddine; Leiknes, TorOve; Shon, Ho Kyong

    2016-06-01

    In this study, a protocol for selecting suitable fertilizer draw solute for anaerobic fertilizer-drawn forward osmosis membrane bioreactor (AnFDFOMBR) was proposed. Among eleven commercial fertilizer candidates, six fertilizers were screened further for their FO performance tests and evaluated in terms of water flux and reverse salt flux. Using selected fertilizers, bio-methane potential experiments were conducted to examine the effect of fertilizers on anaerobic activity due to reverse diffusion. Mono-ammonium phosphate (MAP) showed the highest biogas production while other fertilizers exhibited an inhibition effect on anaerobic activity with solute accumulation. Salt accumulation in the bioreactor was also simulated using mass balance simulation models. Results showed that ammonium sulfate and MAP were the most appropriate for AnFDFOMBR since they demonstrated less salt accumulation, relatively higher water flux, and higher dilution capacity of draw solution. Given toxicity of sulfate to anaerobic microorganisms, MAP appears to be the most suitable draw solution for AnFDFOMBR. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Fertility in midlife women.

    Science.gov (United States)

    Yoldemir, T

    2016-06-01

    Reduced maternal fertility is the consequence of depletion of follicles with maternal aging. In a 35-year-old woman, approximately 9.1% of the residual follicle pool disappears annually without entering into the growing stage, whereas, in a 45-year-old woman, this number triples. After the age of 35 years, the frequency of aneuploidies in oocytes increases sharply. Roughly 50-70% of mature oocytes from a 40-year-old woman have chromosomal abnormalities. The clinical pregnancy and implantation rates are lower in midlife women. Various controlled ovarian stimulation interventions have been suggested for the management of women in advanced age, most of whom are likely to be poor-responder patients. Currently, systematic reviews and meta-analyses suggest that there is insufficient evidence to recommend most of the treatments proposed to improve pregnancy rates in these poor responders. Minimal stimulation or natural cycle in vitro fertilization may be offered, without compromising the already existing pregnancy results.

  3. [Stress and fertility].

    Science.gov (United States)

    Ősapay, György; Ősapay, Klára

    2015-08-30

    In Western countries, sperm quality and fertility of men significantly worsened. Female infertility does not show a better trend either. Subtle defects in the reproductive functions can not be explained by the current methods, and "unexplained infertility" is becoming a more common diagnosis. Every year 1 million couples seek expensive and time consuming fertility treatment in the world. Deeper understanding of an unhealthy lifestyle and the environmental damages may lead to personalized treatments to increase the chance of conception.The effects of various stressors on the male and female reproductive performance were scientifically substantiated by Selye and coworkers in 1976. Cognitive therapy methods can be applied against emotional stressors, supplementation by antioxidants against reactive oxygen compounds, and administration of vitamins and trace elements, especially when deficiency is found, may help before medical intervention on a rational and economical way in the fight against infertility.

  4. Iron absorption in relation to iron status

    International Nuclear Information System (INIS)

    Magnusson, B.; Bjoern-Rasmussen, E.; Hallberg, L.; Rossander, L.

    1981-01-01

    The absorption from a 3 mg dose of ferrous iron was measured in 250 male subjects. The absorption was related to the log concentration of serum ferritin in 186 subjects of whom 99 were regular blood donors (r= -0.76), and to bone marrow haemosiderin grading in 52 subjects with varying iron status. The purpose was to try and establish a percentage absorption from such a dose that is representative of subjects who are borderline iron deficient. This information is necessary for food iron absorption studies in order (1) to calculate the absorption of iron from the diet at a given iron status and (2) compare the absorption of iron from different meals studied in different groups of subjects by different investigarors. The results suggest that an absorption of about 40% of a 3 mg reference dose of ferrous iron is given in a fasting state, roughly corresponds to the absorption in borderline-iron-deficient subjects. The results indicate that this 40% absorption value corresponds to a serum ferritin level of 30 μg/l and that food iron absorption in a group of subjects should be expressed preferably as the absorption corresponding to a reference-dose absorption of 45%, or possibly a serum ferritin level of 30 μg/l. (author)

  5. Fertility preservation 2

    Science.gov (United States)

    De Vos, Michel; Smitz, Johan; Woodruff, Teresa K

    2014-01-01

    Enhanced long-term survival rates of young women with cancer and advances in reproductive medicine and cryobiology have culminated in an increased interest in fertility preservation methods in girls and young women with cancer. Present data suggest that young patients with cancer should be referred for fertility preservation counselling quickly to help with their coping process. Although the clinical application of novel developments, including oocyte vitrification and oocyte maturation in vitro, has resulted in reasonable success rates in assisted reproduction programmes, experience with these techniques in the setting of fertility preservation is in its infancy. It is hoped that these and other approaches, some of which are still regarded as experimental (eg, ovarian tissue cryopreservation, pharmacological protection against gonadotoxic agents, in-vitro follicle growth, and follicle transplantation) will be optimised and become established within the next decade. Unravelling the complex mechanisms of activation and suppression of follicle growth will not only expand the care of thousands of women diagnosed with cancer, but also inform the care of millions of women confronted with reduced reproductive fitness because of ageing. PMID:25283571

  6. Soil and fertilizer nitrogen

    International Nuclear Information System (INIS)

    Winteringham, F.P.W.

    1984-01-01

    As a result of the intensified practices and effectively diminishing land resources per capita, increasing weights of both native soil- and added fertilizer-nitrogen will be lost to agriculture and its products, and will find their way into the environment. Soil-nitrogen levels and contingent productivity can nevertheless be maintained in the face of these losses on the basis of improved soil-N management. In some local situations nitrate levels in water for drinking purposes are likely to continue rising. In some cases agriculture and clearance practices are only one of several sources. In others they are clearly mainly responsible. In developing countries these losses represent those of a relatively increasingly costly input. This is due to the fact that industrial fertilizer nitrogen production is a particularly high energy-consuming process. In the more advanced industrialized countries they represent an addition to the problems and costs of environmental quality and health protection. The programmes, information and data reviewed here suggest that these problems can be contained by improved and extended soil and water management in agriculture on the basis of existing technology. In particular there appears to be enormous scope for the better exploitation of existing legumes both as non-legume crop alternatives or as biofertilizers which also possess more desirable C:N ratios than chemical fertilizer

  7. Fertility impairment in radiotherapy

    Directory of Open Access Journals (Sweden)

    Marta Biedka

    2016-02-01

    Full Text Available Infertility as a result of antineoplastic therapy is becoming a very important issue due to the growing incidence of neoplastic diseases. Routinely applied antineoplastic treatments and the illness itself lead to fertility disorders. Therapeutic methods used in antineoplastic treatment may cause fertility impairment or sterilization due to permanent damage to reproductive cells. The risk of sterilization depends on the patient’s sex, age during therapy, type of neoplasm, radiation dose and treatment area. It is known that chemotherapy and radiotherapy can lead to fertility impairment and the combination of these two gives an additive effect. The aim of this article is to raise the issue of infertility in these patients. It is of growing importance due to the increase in the number of children and young adults who underwent radiotherapy in the past. The progress in antineoplastic therapy improves treatment results, but at the same time requires a deeper look at existential needs of the patient. Reproductive function is an integral element of self-esteem and should be taken into account during therapy planning.

  8. The fertility decline in Kenya.

    Science.gov (United States)

    Robinson, W C; Harbison, S F

    1995-01-01

    In Sub-Saharan Africa Kenya is a prime example of a country experiencing a rapid decline in fertility and greater contraceptive prevalence. These changes have occurred since 1980 when fertility was high at 8.0 children per woman. In 1993 the total fertility rate (TFR) was 5.4, and the growth rate declined to about 2.0%. This transition is swifter than any country in contemporary Asia or historical Europe. The likely projection for Kenya is attainment of replacement level fertility during the 2020s and a leveling of population at about 100 million persons. Fertility has declined the most in urban areas and central and eastern regions. Bongaarts' proximate determinants (TFR, total marital fertility rate, total natural marital fertility rate, and total fecundity) are reduced to the proportion of currently married women using contraception, the proportion in lactational nonfecund status, and the proportion currently married. Actual fertility change is accounted for by total fertility change of 3.0 children. Lactational infecundability accounts for 0.5 potential births, and changes in marital fertility account for 1.0 reduced births per woman. About 70% of fertility reduction is accounted for by contraception and abortion. During 1977-78 80% of fertility control was due to lactational nonfecundity, 10% to nonmarriage, and 10% to contraception. In 1993 lactational nonfecundity accounted for 50% of the reduction, nonmarriage for 20%, and abortion about 30%. Future fertility is expected to be dependent on contraceptive prevalence. Kenya has experienced the Coale paradigm of preconditions necessary for demographic transition (willing, ready, and able). High fertility in Africa is not intractable. Creating the change in attitudes that leads to readiness is linked to education, health, and exposure to modernizing media and urban lifestyles. The public sector family planning program in Kenya has created the opportunity for access and availability of contraception. The key

  9. Chinese culture and fertility decline.

    Science.gov (United States)

    Wu, C; Jia, S

    1992-01-01

    Coale has suggested that cultural factors exert a significant influence on fertility reduction; countries in the "Chinese cultural circle" would be the first to show fertility decline. In China, the view was that traditional Chinese culture contributed to increased population. This paper examines the nature of the relationship between Chinese culture and fertility. Attention was directed to a comparison of fertility rates of developing countries with strong Chinese cultural influence and of fertility within different regions of China. Discussion was followed by an explanation of the theoretical impact of Chinese culture on fertility and direct and indirect beliefs and practices that might either enhance or hinder fertility decline. Emigration to neighboring countries occurred after the Qing dynasty. Fertility after the 1950s declined markedly in Japan, Singapore, Hong Kong, South Korea, Taiwan, and mainland China: all countries within the Chinese cultural circle. Other countries within the Chinese circle which have higher fertility, yet lower fertility than other non-Chinese cultural countries, are Malaysia, Thailand, and Indonesia. Within China, regions with similar fertility patterns are identified as coastal regions, central plains, and mountainous and plateau regions. The Han ethnic group has lower fertility than that of ethnic minorities; regions with large Han populations have lower fertility. Overseas Chinese in East Asian countries also tend to have lower fertility than their host populations. Chinese culture consisted of the assimilation of other cultures over 5000 years. Fertility decline was dependent on the population's desire to limit reproduction, favorable social mechanisms, and availability of contraception: all factors related to economic development. Chinese culture affects fertility reduction by affecting reproductive views and social mechanisms directly, and indirectly through economics. Confucianism emphasizes collectivism, self

  10. Impact of fertilizer plant effluent on water quality

    International Nuclear Information System (INIS)

    Obire, O.; Ogan, A.; Okigbo, R. N.

    2008-01-01

    The impact of National Fertilizer Company of Nigeria out fall effluent on the physico chemistry and bacteriology of Okrika creek was investigated during the sampling period from May to December, 1998. The National Fertilizer Company of Nigeria out fall effluent, the Okrika creek water and the lkpukulubie creek (control) water samples were collected. The physico-chemical parameters analyzed for all the samples included temperature, p H, total chloride, total dissolved solids, dissolved oxygen, conductivity, free ammonia, total phosphate, urea, zinc and iron, while the bacteriological determinations were total culturable aerobic heterotrophic bacteria count and identification of representative isolates. The Okrika creek recorded higher concentrations for all the physicochemical parameters and bacteria load than the control creek. The higher values of p H, Free NH 3 , urea, TDS and the conductivity of the National Fertilizer Company of Nigeria out fall effluent above the FEPA standards reflect the poor effluent quality generated by National Fertilizer Company of Nigeria. The bacteria species isolated from the samples include Aerococcus viridans, Alcaligenes faecalis, Bacillus cereus, Citrobacter freundii, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens and Staphylococcus aureus. In general, the investigation revealed that there was an extremely adverse impact on the physico-chemical and bacteriological water quality characteristics of the Okrika creek as a result of the discharge of poor quality effluent from National Fertilizer Company of Nigeria operations

  11. Slow-release fertilizer

    Science.gov (United States)

    Ming, Douglas W.; Golden, D. C.

    1992-10-01

    A synthetic apatite containing agronutrients and a method for making the apatite are disclosed. The apatite comprises crystalline calcium phosphate having agronutrients dispersed in the crystalline structure. The agronutrients can comprise potassium, magnesium, sulfur, iron, manganese, molybdenum, chlorine, boron, copper and zinc in amounts suited for plant growth. The apatite can optionally comprise a carbonate and/or silicon solubility control agent. The agronutrients are released slowly as the apatite dissolves.

  12. Slow-release fertilizer

    Science.gov (United States)

    Ming, Douglas W. (Inventor); Golden, Dadigamuwage C. (Inventor)

    1995-01-01

    A synthetic apatite containing agronutrients and a method for making the apatite are disclosed. The apatite comprises crystalline calcium phosphate having agronutrients dispersed in the crystalline structure. The agronutrients can comprise potassium, magnesium, sulfur, iron, manganese, molybdenum, chlorine, boron, copper and zinc in amounts suited for plant growth. The apatite can optionally comprise a carbonate and/or silicon solubility control agent. The agronutrients are released slowly as the apatite dissolves.

  13. Theoretical Investigation of Hydrogen Adsorption and Dissociation on Iron and Iron Carbide Surfaces Using the ReaxFF Reactive Force Field Method

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Chenyu; van Duin, Adri C.T.; Sorescu, Dan C.

    2012-06-01

    We have developed a ReaxFF reactive force field to describe hydrogen adsorption and dissociation on iron and iron carbide surfaces relevant for simulation of Fischer–Tropsch (FT) synthesis on iron catalysts. This force field enables large system (>>1000 atoms) simulations of hydrogen related reactions with iron. The ReaxFF force field parameters are trained against a substantial amount of structural and energetic data including the equations of state and heats of formation of iron and iron carbide related materials, as well as hydrogen interaction with iron surfaces and different phases of bulk iron. We have validated the accuracy and applicability of ReaxFF force field by carrying out molecular dynamics simulations of hydrogen adsorption, dissociation and recombination on iron and iron carbide surfaces. The barriers and reaction energies for molecular dissociation on these two types of surfaces have been compared and the effect of subsurface carbon on hydrogen interaction with iron surface is evaluated. We found that existence of carbon atoms at subsurface iron sites tends to increase the hydrogen dissociation energy barrier on the surface, and also makes the corresponding hydrogen dissociative state relatively more stable compared to that on bare iron. These properties of iron carbide will affect the dissociation rate of H{sub 2} and will retain more surface hydride species, thus influencing the dynamics of the FT synthesis process.

  14. Changes in Serum Ferritin and Other Factors Associated with Iron Metabolism During Chronic Hyperbaric Exposure

    National Research Council Canada - National Science Library

    Gilman, Sara C; Hunter, Jr., W. L; Mooney, L. W

    1979-01-01

    .... during these simulated dives progressive and correlated increases in serum ferritin and iron occurred. No significant changes were observed in bilirubin, hemoglobin, neurloplasmia, transferrin, cooper, or total iron binding capacity...

  15. Immunosuppressive drugs and fertility.

    Science.gov (United States)

    Leroy, Clara; Rigot, Jean-Marc; Leroy, Maryse; Decanter, Christine; Le Mapihan, Kristell; Parent, Anne-Sophie; Le Guillou, Anne-Claire; Yakoub-Agha, Ibrahim; Dharancy, Sébastien; Noel, Christian; Vantyghem, Marie-Christine

    2015-10-21

    Immunosuppressive drugs are used in the treatment of inflammatory and autoimmune diseases, as well as in transplantation. Frequently prescribed in young people, these treatments may have deleterious effects on fertility, pregnancy outcomes and the unborn child. This review aims to summarize the main gonadal side effects of immunosuppressants, to detail the effects on fertility and pregnancy of each class of drug, and to provide recommendations on the management of patients who are seen prior to starting or who are already receiving immunosuppressive treatment, allowing them in due course to bear children. The recommendations for use are established with a rather low level of proof, which needs to be taken into account in the patient management. Methotrexate, mycophenolate, and le- and teri-flunomide, cyclophosphamide, mitoxanthrone are contraindicated if pregnancy is desired due to their teratogenic effects, as well as gonadotoxic effects in the case of cyclophosphamide. Anti-TNF-alpha and mTOR-inhibitors are to be used cautiously if pregnancy is desired, since experience using these drugs is still relatively scarce. Azathioprine, glucocorticoids, mesalazine, anticalcineurins such as cyclosporine and tacrolimus, ß-interferon, glatiramer-acetate and chloroquine can be used during pregnancy, bearing in mind however that side effects may still occur. Experience is limited concerning natalizumab, fingolimod, dimethyl-fumarate and induction treatments. Conclusion: At the time of prescription, patients must be informed of the possible consequences of immunosuppressants on fertility and of the need for contraception. Pregnancy must be planned and the treatment modified if necessary in a pre-conception time period adapted to the half-life of the drug, imperatively in relation with the prescriber of the immunosuppressive drugs.

  16. Ethnicity and fertility in Nigeria.

    Science.gov (United States)

    Kollehlon, Konia T

    2003-01-01

    Using a sample of Hausa-Fulani, Yoruba, Ibo, and all other women from the 1990 Nigerian Demographic and Health Survey, this study examines ethnic fertility differentials in Nigeria within the context of the social characteristics and cultural hypotheses. Among all women, we find the net fertility of Hausa-Fulani women to be lower than that of Other women; with no statistically significant difference in the net fertility of Ibo, Yourba, and Other women. But, among currently married women, we find the net fertility of Hausa-Fulani and Yoruba women to be lower than that of Other women, while the net fertility of Ibo women is higher than that of Other women. Overall, the findings of this study are more consistent with the cultural hypothesis, because statistically significant fertility differentials by ethnicity remain, even after controlling for selected socioeconomic and demographic variables.

  17. Temporal Trends in Fertility Rates

    DEFF Research Database (Denmark)

    Jensen, Martin Blomberg; Priskorn, Lærke; Jensen, Tina Kold

    2015-01-01

    OBJECTIVE: Increasing age at first childbirth has been suggested to increase the risk for infertility. Our objective is to determine whether women above thirty years of age historically have been able to sustain fertility rates above replacement level. DESIGN: A descriptive nationwide Danish study...... to determine total and age specific fertility rates. RESULTS: Total fertility rate (TFR) decreased from 4.1 to 1.8 children per woman and age specific fertility also decreased from 1901 to 2014. Women aged 30-34, 35-39 or 40-44 years in the first decade of the 20th century had higher fertility rates than...... for 10% of TFR in 1901 compared with 4% in 2014 despite usage of assisted reproduction. CONCLUSION: This nationwide study shows that women above 30 years of age historically have been able to sustain fertility rates above replacement level. This implies that other factors besides age are strong...

  18. Fertility and age

    Directory of Open Access Journals (Sweden)

    Korula George

    2010-01-01

    Full Text Available The changing social scenario together with economic growth and an increase in job opportunities has to a great extent reduced gender inequality and has resulted in more and more older women seeking help from infertility clinics. Fertility and aging have always been closely linked and the age of the female partner remains the single most important factor in predicting success with treatment. Although tests for the ovarian reserve are an important informative tool and are helpful in selecting treatment options, they are poor predictors of the outcome.

  19. Fertility trends in Singapore.

    Science.gov (United States)

    Singh, K; Viegas, O; Ratnam, S S

    1988-10-01

    In 1966, the Singapore National Family Planning and Population Program established the goal of reaching replacement fertility by 1990 and zero population growth by the year 2030. To achieve this goal, the government relied on a series of incentives and disincentives to discourage births above the 3rd birth order, including tax relief for the 1st 3 children only, paid medical leave for women undergoing sterilization after the 3rd or subsequent birth, monetary stipends in some cases where the mother is sterilized after the 1st or 2nd birth, and increasing accouchement charges for increasing birth orders. Also important to demographic planning were liberalization of Singapore's abortion legislation and more aggressive promotion of contraception. As a result of these efforts, Singapore's crude birth rate has declined from 29.5/1000 population in 1965 to 16.6/1000 in 1985. Also observed have been dramatic declines in infant mortality in this same period, from 26.2/1000 live births to 9.3/1000, and in maternal mortality, from 52/100,000 live births to 10/100,000. In 1985, 42% of total births were to women in the 25-29-year age group. The numbers of 4th and later births fell by 90% between 1966 and 1985. The total fertility rate has declined from 4.6/woman in 1965 to 3.1 in 1970 to 1.6 in 1986. Below replacement level fertility was achieved in 1975, in part because of government policy but also as a result of cultural and socioeconomic factors such as increasing female labor force participation rates, a break-up of the extended family system, a rise in the age at 1st marriage, and rises in educational attainment. The drop in fertility was contributed mainly by the higher socioeconomic class, more affluent, and educated Singaporeans. Thus, in 1981, the government introduced certain pronatalist policies and incentives to encourage better educated women to produce more children, e.g., tax relief and the elimination of monetary incentives to sterilization acceptors above a

  20. FERTILIZER RECOMMENDATION SYSTEM FOR MELON BASED ON NUTRITIONAL BALANCE

    Directory of Open Access Journals (Sweden)

    José Aridiano Lima de Deus

    2015-04-01

    Full Text Available Melon is one of the most demanding cucurbits regarding fertilization, requiring knowledge of soils, crop nutritional requirements, time of application, and nutrient use efficiency for proper fertilization. Developing support systems for decision-making for fertilization that considers these variables in nutrient requirement and supply is necessary. The objective of this study was parameterization of a fertilizer recommendation system for melon (Ferticalc-melon based on nutritional balance. To estimate fertilizer recommendation, the system considers the requirement subsystem (REQ, which includes the demand for nutrients by the plant, and the supply subsystem (SUP, which corresponds to the supply of nutrients through the soil and irrigation water. After determining the REQtotal and SUPtotal, the system calculates the nutrient balances for N, P, K, Ca, Mg, and S, recommending fertilizer application if the balance is negative (SUP < REQ, but not if the balance is positive or zero (SUP ≥ REQ. Simulations were made for different melon types (Yellow, Cantaloupe, Galia and Piel-de-sapo, with expected yield of 45 t ha-1. The system estimated that Galia type was the least demanding in P, while Piel-de-sapo was the most demanding. Cantaloupe was the least demanding for N and Ca, while the Yellow type required less K, Mg, and S. As compared to other fertilizer recommendation methods adopted in Brazil, the Ferticalc system was more dynamic and flexible. Although the system has shown satisfactory results, it needs to be evaluated under field conditions to improve its recommendations.

  1. Does fertility decrease household consumption?

    OpenAIRE

    Jungho Kim; Henriette Engelhardt; Alexia Fürnkranz-Prskawetz; Arnstein Aassve

    2009-01-01

    This paper presents an empirical analysis of the relationship between fertility and a direct measure of poverty for Indonesia, a country, which has experienced unprecedented economic growth and sharp fertility declines over recent decades. It focuses on illustrating the sensitivity of the effect of fertility on household consumption with respect to the equivalence scale by applying the propensity score matching method. The analysis suggests that a newborn child decreases household consumption...

  2. Iron Deficiency Anemia: Focus on Infectious Diseases in Lesser Developed Countries

    Science.gov (United States)

    Shaw, Julia G.; Friedman, Jennifer F.

    2011-01-01

    Iron deficiency anemia is thought to affect the health of more than one billion people worldwide, with the greatest burden of disease experienced in lesser developed countries, particularly women of reproductive age and children. This greater disease burden is due to both nutritional and infectious etiologies. Individuals in lesser developed countries have diets that are much lower in iron, less access to multivitamins for young children and pregnant women, and increased rates of fertility which increase demands for iron through the life course. Infectious diseases, particularly parasitic diseases, also lead to both extracorporeal iron loss and anemia of inflammation, which decreases bioavailability of iron to host tissues. This paper will address the unique etiologies and consequences of both iron deficiency anemia and the alterations in iron absorption and distribution seen in the context of anemia of inflammation. Implications for diagnosis and treatment in this unique context will also be discussed. PMID:21738863

  3. Iron Deficiency Anemia: Focus on Infectious Diseases in Lesser Developed Countries

    Directory of Open Access Journals (Sweden)

    Julia G. Shaw

    2011-01-01

    Full Text Available Iron deficiency anemia is thought to affect the health of more than one billion people worldwide, with the greatest burden of disease experienced in lesser developed countries, particularly women of reproductive age and children. This greater disease burden is due to both nutritional and infectious etiologies. Individuals in lesser developed countries have diets that are much lower in iron, less access to multivitamins for young children and pregnant women, and increased rates of fertility which increase demands for iron through the life course. Infectious diseases, particularly parasitic diseases, also lead to both extracorporeal iron loss and anemia of inflammation, which decreases bioavailability of iron to host tissues. This paper will address the unique etiologies and consequences of both iron deficiency anemia and the alterations in iron absorption and distribution seen in the context of anemia of inflammation. Implications for diagnosis and treatment in this unique context will also be discussed.

  4. Magnetic mapping of distribution of wood ash used for fertilization of forest soil

    Czech Academy of Sciences Publication Activity Database

    Petrovský, Eduard; Remeš, J.; Kapička, Aleš; Podrázský, V.; Grison, Hana; Borůvka, L.

    2018-01-01

    Roč. 626, June (2018), s. 228-234 ISSN 0048-9697 Institutional support: RVO:67985530 Keywords : forest soil * wood ash * fertilizing * tree plants * iron oxides * rock magnetism Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 4.900, year: 2016

  5. The capture and destruction of E. coli from simulated urban runoff using conventional bioretention media and iron oxide-coated sand

    Science.gov (United States)

    Given the magnitude of the threat to the quality of receiving water bodies posed by microbial pollutants in urban stormwater runoff, and the untested potential for their removal in bioretention systems, studies were performed to evaluate the removal efficiency of bacteria from simulated urban stormw...

  6. Fertility differentials in rural Bangladesh.

    Science.gov (United States)

    Khan, H T; Islam, S M; Khan, H M; Bari, R

    1993-01-01

    "Data from two sources in rural Bangladesh have been used in this study to examine the differentials in fertility by selected socio-economic and demographic factors. Results [indicate] that age at first marriage, education of spouses and availability of electricity in the household...have [an] inverse relationship with fertility. Higher fertility is observed for Muslim women than for non-Muslims. It has been found that fertility is the lowest to those women whose husbands are service holders and the highest for agriculture." excerpt

  7. Fertilization compatibility of spawning corals

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set includes experimental results of fertilization assays to characterize genetic compatibility between individual parental genotypes. Targeted species...

  8. Iron-Deficiency Anemia

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    Full Text Available ... fatigue or tiredness, shortness of breath, or chest pain. If your doctor diagnoses you with iron-deficiency ... Common symptoms of iron-deficiency anemia include: Chest pain Coldness in the hands and feet Difficulty concentrating ...

  9. Iron-Deficiency Anemia

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    Full Text Available ... body to absorb iron from the gastrointestinal tract (GI tract). Blood loss When you lose blood, you ... to iron-deficiency anemia include: Bleeding in your GI tract, from an ulcer, colon cancer, or regular ...

  10. Iron-Deficiency Anemia

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    Full Text Available ... complications, including heart failure and development delays in children. Explore this Health ... red blood cells. Iron-deficiency anemia usually develops over time because your body’s intake of iron ...

  11. Iron-Deficiency Anemia

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    Full Text Available ... heart failure . Increased risk of infections Motor or cognitive development delays in children Pregnancy complications, such as ... for iron-deficiency anemia. Learn about exciting research areas that NHLBI is exploring about iron-deficiency anemia. ...

  12. Iron-Deficiency Anemia

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    Full Text Available ... Health and Human Development, we are investigating how best to treat premature newborns with low hemoglobin levels. ... are hoping to determine which iron supplements work best to treat iron-deficiency anemia in children who ...

  13. Iron-Deficiency Anemia

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    Full Text Available ... your doctor may recommend changes to help you meet the recommended daily amount of iron. If you ... stop bleeding. Healthy lifestyle changes To help you meet your daily recommended iron levels, your doctor may ...

  14. Iron-Deficiency Anemia

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    Full Text Available ... an MCV of less than 80 femtoliters (fL). Prevention strategies If you have certain risk factors , such ... drinking black tea, which reduces iron absorption. Other treatments If you have chronic kidney disease and iron- ...

  15. Iron-Deficiency Anemia

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    Full Text Available ... same for boys and girls. From birth to 6 months, babies need 0.27 mg of iron. ... for iron deficiency at certain ages: Infants between 6 and 12 months, especially if they are fed ...

  16. Iron-Deficiency Anemia

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    Full Text Available ... your blood may be normal even if the total amount of iron in your body is low. ... iron-deficiency anemia in blood donors affects the quality of donated red blood cells, such as how ...

  17. Iron-Deficiency Anemia

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    Full Text Available ... of the condition. Your doctor may recommend healthy eating changes, iron supplements, intravenous iron therapy for mild ... less Look for Treatment will discuss medicines and eating pattern changes that your doctors may recommend if ...

  18. Iron-Deficiency Anemia

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    Full Text Available ... Disorders Lung Diseases Heart and Vascular Diseases Precision Medicine Activities Obesity, Nutrition, and Physical Activity Population and ... lose blood, you lose iron. Certain conditions or medicines can cause blood loss and lead to iron- ...

  19. Iron-Deficiency Anemia

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    Full Text Available ... absorb iron and lead to iron-deficiency anemia. These conditions include: Intestinal and digestive conditions, such as ... tract. Inflammation from congestive heart failure or obesity . These chronic conditions can lead to inflammation that may ...

  20. Iron-Deficiency Anemia

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    Full Text Available ... C to help your body absorb iron. Avoid drinking black tea, which reduces iron absorption. Other treatments ... improve health through research and scientific discovery. Improving health with current research Learn about the following ways ...

  1. Iron-Deficiency Anemia

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    Full Text Available ... higher risk, as most of a newborn’s iron stores are developed during the third trimester of pregnancy. ... red blood cells on hand, their bodies can store iron to prepare for blood loss during delivery. ...

  2. Iron-Deficiency Anemia

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    Full Text Available ... may be diagnosed with iron-deficiency anemia if you have low iron or ferritin levels in your blood. More testing may be needed to rule out other types of anemia. Tests for gastrointestinal ...

  3. Iron-Deficiency Anemia

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    Full Text Available ... were born prematurely may be at an even higher risk, as most of a newborn’s iron stores ... men of the same age. Women are at higher risk for iron-deficiency anemia under some circumstances, ...

  4. Iron supplements (image)

    Science.gov (United States)

    The mineral iron is an essential nutrient for humans because it is part of blood cells, which carry oxygen to all body cells. There is no conclusive evidence that iron supplements contribute to heart attacks.

  5. Total iron binding capacity

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003489.htm Total iron binding capacity To use the sharing features on this page, please enable JavaScript. Total iron binding capacity (TIBC) is a blood test to ...

  6. Iron-Deficiency Anemia

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    Full Text Available ... may require intravenous (IV) iron therapy or a blood transfusion . Iron supplements Your doctor may recommend that you ... Anemia Aplastic Anemia Arrhythmia Blood Donation Blood Tests Blood Transfusion Heart-Healthy Lifestyle Changes Heart Failure Hemolytic Anemia ...

  7. Iron-Deficiency Anemia

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    Full Text Available ... iron from the gastrointestinal tract (GI tract). Blood loss When you lose blood, you lose iron. Certain ... domestic small businesses that have strong potential for technology commercialization through the Small Business Innovation Research (SBIR) ...

  8. Iron-Deficiency Anemia

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    Full Text Available ... iron-rich foods, especially during certain stages of life when more iron is needed, such as ... to advancing science and translating discoveries into clinical practice to promote ...

  9. Iron-Deficiency Anemia

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    Full Text Available ... also often take other medicines—such as proton pump inhibitors, anticoagulants, or blood thinners—that may cause iron-deficiency anemia. Proton pump inhibitors interfere with iron absorption, and blood thinners ...

  10. Iron-Deficiency Anemia

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    Full Text Available ... Look for Treatment will discuss medicines and eating pattern changes that your doctors may recommend if you ... iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, such as ...

  11. Iron-Deficiency Anemia

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    Full Text Available ... striking the ground, such as with marathon runners. Sex Girls and women between the ages of 14 ... developing iron-deficiency anemia. Foods that are good sources of iron include dried beans, dried fruits, eggs, ...

  12. Iron-Deficiency Anemia

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    Full Text Available ... increase your risk for iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron- ... factors , such as if you are following a vegetarian eating pattern, your doctor may recommend changes to ...

  13. Iron-Deficiency Anemia

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    Full Text Available ... deficiency anemia. Proton pump inhibitors interfere with iron absorption, and blood thinners increase the likelihood of bleeding ... oranges, strawberries, and tomatoes, may help increase your absorption of iron. If you are pregnant, talk to ...

  14. Iron-Deficiency Anemia

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    Full Text Available ... Not eating enough iron-rich foods, such as meat and fish, may result in you getting less ... include dried beans, dried fruits, eggs, lean red meat, salmon, iron-fortified breads and cereals, peas, tofu, ...

  15. Iron-Deficiency Anemia

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    Full Text Available ... mg and women need 18 mg. After age 51, both men and women need 8 mg. Pregnant ... for iron-deficiency anemia. Learn about exciting research areas that NHLBI is exploring about iron-deficiency anemia. ...

  16. Iron-Deficiency Anemia

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    Full Text Available ... iron-deficiency anemia. These conditions include: Intestinal and digestive conditions, such as celiac disease; inflammatory bowel diseases, ... iron-deficiency anemia , such as bleeding in the digestive or urinary tract or heavy menstrual bleeding, your ...

  17. Iron-Deficiency Anemia

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    Full Text Available ... prevent complications such as abnormal heart rhythms and depression. Learn the warning signs of serious complications and ... donors for low iron stores. Reliable point-of-care testing may help identify iron deficiency before potentially ...

  18. Iron-Deficiency Anemia

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    Full Text Available ... breastfeeding women older than 18 need 9 mg. Problems absorbing iron Even if you consume the recommended ... interested in learning how having iron-deficiency anemia early in life affects later behavior, thinking, and mood ...

  19. Iron-Deficiency Anemia

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    Full Text Available ... conditions that can cause iron-deficiency anemia. Blood tests to screen for iron-deficiency anemia To screen ... the size of your liver and spleen. Blood tests Based on results from blood tests to screen ...

  20. Iron-Deficiency Anemia

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    Full Text Available ... as most of a newborn’s iron stores are developed during the third trimester of pregnancy. Children between ... This makes it harder to stop bleeding and can increase the risk of iron-deficiency anemia from ...

  1. Iron-Deficiency Anemia

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    Full Text Available ... your doctor may recommend you eat heart-healthy foods or control other conditions that can cause iron-deficiency anemia. Blood tests to screen for iron-deficiency anemia To screen ...

  2. Iron-Deficiency Anemia

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    Full Text Available ... have less hemoglobin than normal. Hemoglobin is a protein inside red blood cells that carries oxygen from ... stored iron has been used. Ferritin is a protein that helps store iron in your body. Reticulocyte ...

  3. Iron-Deficiency Anemia

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    Full Text Available ... and Strategic Vision Leadership Scientific Divisions Operations and Administration Advisory Committees Budget and Legislative Information Jobs and ... blood cells. Iron-deficiency anemia usually develops over time because your body’s intake of iron is too ...

  4. Iron-Deficiency Anemia

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    Full Text Available ... vegan eating patterns. Not eating enough iron-rich foods, such as meat and fish, may result in ... be hard to get the recommended amount from food alone. Pregnant women need more iron to support ...

  5. Iron-Deficiency Anemia

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    Full Text Available ... learning how having iron-deficiency anemia early in life affects later behavior, thinking, and mood during adolescence. ... iron-deficiency anemia in blood donors affects the quality of donated red blood cells, such as how ...

  6. Iron-Deficiency Anemia

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    Full Text Available ... iron-deficiency anemia in blood donors affects the quality of donated red blood cells, such as how ... Cells From Iron-deficient Donors: Recovery and Storage Quality. Learn more about participating in a clinical trial . ...

  7. Iron-Deficiency Anemia

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    Full Text Available ... endoscopy or colonoscopy, to stop bleeding. Healthy lifestyle changes To help you meet your daily recommended iron ... iron-deficiency anemia early in life affects later behavior, thinking, and mood during adolescence. Treating anemia in ...

  8. Iron-Deficiency Anemia

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    Full Text Available ... family history and genetics , lifestyle habits, or sex. Age You may be at increased risk for iron ... Signs, Symptoms, and Complications Iron-deficiency anemia can range from mild to severe. People with mild or ...

  9. Iron-Deficiency Anemia

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    Full Text Available ... leaving cells where it is stored or from being absorbed in the duodenum, the first part of ... treatments for iron-deficiency anemia. Living With After being diagnosed with iron-deficiency anemia, it is important ...

  10. Iron-Deficiency Anemia

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    Full Text Available ... iron to prepare for blood loss during delivery. Screening and Prevention Your doctor may screen you for ... and symptoms of iron-deficiency anemia. Return to Screening and Prevention to review tests to screen for ...

  11. Iron-Deficiency Anemia

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    Full Text Available ... Teens, who have increased need for iron during growth spurts. Older adults, especially those over age 65. ... need for iron increases during these periods of growth and development, and it may be hard to ...

  12. Iron-Deficiency Anemia

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    Full Text Available ... endoscopy or colonoscopy, to stop bleeding. Healthy lifestyle changes To help you meet your daily recommended iron ... tofu, dried fruits, and spinach and other dark green leafy vegetables. You can also take an iron ...

  13. Computational modeling and analysis of iron release from macrophages.

    Directory of Open Access Journals (Sweden)

    Alka A Potdar

    2014-07-01

    Full Text Available A major process of iron homeostasis in whole-body iron metabolism is the release of iron from the macrophages of the reticuloendothelial system. Macrophages recognize and phagocytose senescent or damaged erythrocytes. Then, they process the heme iron, which is returned to the circulation for reutilization by red blood cell precursors during erythropoiesis. The amount of iron released, compared to the amount shunted for storage as ferritin, is greater during iron deficiency. A currently accepted model of iron release assumes a passive-gradient with free diffusion of intracellular labile iron (Fe2+ through ferroportin (FPN, the transporter on the plasma membrane. Outside the cell, a multi-copper ferroxidase, ceruloplasmin (Cp, oxidizes ferrous to ferric ion. Apo-transferrin (Tf, the primary carrier of soluble iron in the plasma, binds ferric ion to form mono-ferric and di-ferric transferrin. According to the passive-gradient model, the removal of ferrous ion from the site of release sustains the gradient that maintains the iron release. Subcellular localization of FPN, however, indicates that the role of FPN may be more complex. By experiments and mathematical modeling, we have investigated the detailed mechanism of iron release from macrophages focusing on the roles of the Cp, FPN and apo-Tf. The passive-gradient model is quantitatively analyzed using a mathematical model for the first time. A comparison of experimental data with model simulations shows that the passive-gradient model cannot explain macrophage iron release. However, a facilitated-transport model associated with FPN can explain the iron release mechanism. According to the facilitated-transport model, intracellular FPN carries labile iron to the macrophage membrane. Extracellular Cp accelerates the oxidation of ferrous ion bound to FPN. Apo-Tf in the extracellular environment binds to the oxidized ferrous ion, completing the release process. Facilitated-transport model can

  14. Iron absorption studies

    International Nuclear Information System (INIS)

    Ekenved, G.

    1976-01-01

    The main objective of the present work was to study iron absorption from different iron preparations in different types of subjects and under varying therapeutic conditions. The studies were performed with different radioiron isotope techniques and with a serum iron technique. The preparations used were solutions of ferrous sulphate and rapidly-disintegrating tablets containing ferrous sulphate, ferrous fumarate and ferrous carbonate and a slow-release ferrous sulphate tablet of an insoluble matrix type (Duroferon Durules). The serum iron method was evaluated and good correlation was found between the serum iron response and the total amount of iron absorbed after an oral dose of iron given in solution or in tablet form. New technique for studying the in-vivo release properties of tablets was presented. Iron tablets labelled with a radio-isotope were given to healthy subjects. The decline of the radioactivity in the tablets was followed by a profile scanning technique applied to different types of iron tablets. The release of iron from the two types of tablets was shown to be slower in vivo than in vitro. It was found that co-administration of antacids and iron tablets led to a marked reduction in the iron absorption and that these drugs should not be administered sumultaneously. A standardized meal markedly decreased the absorbability of iron from iron tablets. The influence of the meal was more marked with rapidly-disintegrating than with slow-release ferrous sulphate tablets. The absorption from rapidly-disintegrating and slow-release ferrous sulphate tablets was compared under practical clinical conditions during an extended treatment period. The studies were performed in healthy subjects, blood donors and patients with iron deficiency anaemia and it was found that the absorption of iron from the slow-release tablets was significantly better than from the rapidly-disintegrating tablets in all three groups of subjects. (author)

  15. High-rate behaviour of iron ore pellet

    Science.gov (United States)

    Gustafsson, Gustaf; Häggblad, Hans-Åke; Jonsén, Pär; Nishida, Masahiro

    2015-09-01

    Iron ore pellets are sintered, centimetre-sized spheres of ore with high iron content. Together with carbonized coal, iron ore pellets are used in the production of steel. In the transportation from the pelletizing plants to the customers, the iron ore pellets are exposed to different loading situations, resulting in degradation of strength and in some cases fragmentation. For future reliable numerical simulations of the handling and transportation of iron ore pellets, knowledge about their mechanical properties is needed. This paper describes the experimental work to investigate the dynamic mechanical properties of blast furnace iron ore pellets. To study the dynamic fracture of iron ore pellets a number of split Hopkinson pressure bar tests are carried out and analysed.

  16. Atmospheric processing of iron carried by mineral dust

    Directory of Open Access Journals (Sweden)

    S. Nickovic

    2013-09-01

    Full Text Available Nutrification of the open ocean originates mainly from deposited aerosol in which the bio-avaliable iron is likely to be an important factor. The relatively insoluble iron in dust from arid soils becomes more soluble after atmospheric processing and, through its deposition in the ocean, could contribute to marine primary production. To numerically simulate the atmospheric route of iron from desert sources to sinks in the ocean, we developed a regional atmospheric dust-iron model that included parameterization of the transformation of iron to a soluble form caused by dust mineralogy, cloud processes and solar radiation. When compared with field data on the aerosol iron, which were collected during several Atlantic cruises, the results from the higher-resolution simulation experiments showed that the model was capable of reproducing the major observed patterns.

  17. Household Fertilizers Use and Soil Fertility Management Practices ...

    African Journals Online (AJOL)

    Household Fertilizers Use and Soil Fertility Management Practices in Vegetable Crops Production: The Case of Central Rift Valley of Ethiopia. ... rate, which could leads to pollution of the environment from over dose application and from runoff in to the water bodies and leaching in to the ground water with economic loss.

  18. Fertile ground? : soil fertility management and the African smallholder

    NARCIS (Netherlands)

    Misiko, M.

    2007-01-01

    Keywords: smallholder farmers, soil fertility, experimentation, "inconvenience", realist.The focus in this thesis is to form a view of how well soil fertility research performs within the ever shifting smallholder contexts. This study examined application of agro-ecological

  19. Iron-Deficiency Anemia

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    Full Text Available ... iron, in milligrams (mg) at different ages and stages of life. Until the teen years, the recommended amount of ... and choosing iron-rich foods, especially during certain stages of life when more iron is needed, such as childhood ...

  20. Iron-Deficiency Anemia

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    Full Text Available ... iron-fortified breads and cereals, peas, tofu, dried fruits, and dark green leafy vegetables. Foods rich in vitamin C, such as oranges, ... iron-fortified breads and cereals, beans, tofu, dried fruits, and spinach and other dark green leafy vegetables. You can also take an iron supplement. Follow ...

  1. Iron-Deficiency Anemia

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    Full Text Available ... because your body’s intake of iron is too low. Low intake of iron can happen because of blood ... a lot of cow’s milk. Cow’s milk is low in iron. Teens, who have increased need for ...

  2. Iron-Deficiency Anemia

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    Full Text Available ... This is sometimes used to deliver iron through a blood vessel to increase iron levels in the blood. One benefit of IV iron ... over 65 years of age had low hemoglobin levels. This was associated with a greater risk of death even with mild anemia. ...

  3. Iron-Deficiency Anemia

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    Full Text Available ... Heart and Vascular Diseases Precision Medicine Activities Obesity, Nutrition, and Physical Activity Population and Epidemiology Studies Women’s ... making new blood cells. Visit our Aplastic Anemia Health Topic to learn more. ... recommend that you take iron supplements, also called iron pills or oral iron, by mouth once or several times a ...

  4. Iron-Deficiency Anemia

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    Full Text Available ... supplements. Iron supplements can change how certain medicines work. Your doctor may suggest check-ups to make sure your ... To prevent complications from iron-deficiency anemia, your doctor may ... during certain stages of life when more iron is needed, such as childhood ...

  5. Iron-Deficiency Anemia

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    Full Text Available ... if you are diagnosed with iron-deficiency anemia. Risk Factors You may have an increased risk for iron-deficiency anemia because of your age, ... or sex. Age You may be at increased risk for iron deficiency at certain ages: Infants between ...

  6. Iron and Immunity

    NARCIS (Netherlands)

    Verbon, E.H.|info:eu-repo/dai/nl/413534049; Trapet, P.L.; Stringlis, I.|info:eu-repo/dai/nl/41185206X; Kruijs, Sophie; Bakker, P.A.H.M.|info:eu-repo/dai/nl/074744623; Pieterse, C.M.J.|info:eu-repo/dai/nl/113115113

    2017-01-01

    Iron is an essential nutrient for most life on Earth because it functions as a crucial redox catalyst in many cellular processes. However, when present in excess iron can lead to the formation of harmful hydroxyl radicals. Hence, the cellular iron balance must be tightly controlled. Perturbation of

  7. Glutathione, Glutaredoxins, and Iron.

    Science.gov (United States)

    Berndt, Carsten; Lillig, Christopher Horst

    2017-11-20

    Glutathione (GSH) is the most abundant cellular low-molecular-weight thiol in the majority of organisms in all kingdoms of life. Therefore, functions of GSH and disturbed regulation of its concentration are associated with numerous physiological and pathological situations. Recent Advances: The function of GSH as redox buffer or antioxidant is increasingly being questioned. New functions, especially functions connected to the cellular iron homeostasis, were elucidated. Via the formation of iron complexes, GSH is an important player in all aspects of iron metabolism: sensing and regulation of iron levels, iron trafficking, and biosynthesis of iron cofactors. The variety of GSH coordinated iron complexes and their functions with a special focus on FeS-glutaredoxins are summarized in this review. Interestingly, GSH analogues that function as major low-molecular-weight thiols in organisms lacking GSH resemble the functions in iron homeostasis. Since these iron-related functions are most likely also connected to thiol redox chemistry, it is difficult to distinguish between mechanisms related to either redox or iron metabolisms. The ability of GSH to coordinate iron in different complexes with or without proteins needs further investigation. The discovery of new Fe-GSH complexes and their physiological functions will significantly advance our understanding of cellular iron homeostasis. Antioxid. Redox Signal. 27, 1235-1251.

  8. Iron Stain on Wood

    Science.gov (United States)

    Mark Knaebe

    2013-01-01

    Iron stain, an unsightly blue–black or gray discoloration, can occur on nearly all woods. Oak, redwood, cypress, and cedar are particularly prone to iron stain because these woods contain large amounts of tannin-like extractives. The discoloration is caused by a chemical reaction between extractives in the wood and iron in steel products, such as nails, screws, and...

  9. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... amounts of iron, in milligrams (mg) at different ages and stages of life. Until the teen years, the recommended amount of iron is the same for boys and girls. From birth to 6 months, babies need 0.27 mg of iron. This number goes up to 11 mg for children ages 7 to 12 months, and down to 7 ...

  10. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... bleeding or other abnormalities, such as growths or cancer of the lining of the colon. For this test, a ... that you take iron supplements, also called iron pills or oral iron, by mouth once or several times a ...

  11. Iron homeostasis during pregnancy.

    Science.gov (United States)

    Fisher, Allison L; Nemeth, Elizabeta

    2017-12-01

    During pregnancy, iron needs to increase substantially to support fetoplacental development and maternal adaptation to pregnancy. To meet these iron requirements, both dietary iron absorption and the mobilization of iron from stores increase, a mechanism that is in large part dependent on the iron-regulatory hormone hepcidin. In healthy human pregnancies, maternal hepcidin concentrations are suppressed in the second and third trimesters, thereby facilitating an increased supply of iron into the circulation. The mechanism of maternal hepcidin suppression in pregnancy is unknown, but hepcidin regulation by the known stimuli (i.e., iron, erythropoietic activity, and inflammation) appears to be preserved during pregnancy. Inappropriately increased maternal hepcidin during pregnancy can compromise the iron availability for placental transfer and impair the efficacy of iron supplementation. The role of fetal hepcidin in the regulation of placental iron transfer still remains to be characterized. This review summarizes the current understanding and addresses the gaps in knowledge about gestational changes in hematologic and iron variables and regulatory aspects of maternal, fetal, and placental iron homeostasis. © 2017 American Society for Nutrition.

  12. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Topics section only, or the News and Resources section. NHLBI Entire Site NHLBI Entire Site Health ... español Iron-deficiency anemia is a common type of anemia that occurs if you do not have enough iron in your body. People with mild or moderate iron-deficiency anemia ...

  13. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... for iron-deficiency anemia. Lifestyle habits Certain lifestyle habits may increase your risk for iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, such as meat and fish, may result in ...

  14. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... blood cells. Iron-deficiency anemia usually develops over time because your body’s intake of iron is too ... clamping of your newborn’s umbilical cord at the time of delivery. This may help prevent iron-deficiency ...

  15. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... severity of the condition. Your doctor may recommend healthy eating changes, iron supplements, intravenous iron therapy for mild ... you: Adopt healthy lifestyle changes such as heart-healthy eating patterns. Increase your daily intake of iron-rich ...

  16. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, such as meat and fish, may result in you getting less than the recommended daily amount of iron. Frequent blood donation. Individuals who donate blood often may be ...

  17. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Topics News & Resources Intramural Research Home / < Back To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer ... and symptoms as well as complications from iron-deficiency anemia. Research for Your Health The NHLBI is part of the U.S. Department ...

  18. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... anemia, your doctor may order the following blood tests to diagnose iron-deficiency anemia: Complete blood count (CBC) to ... than normal when viewed under a microscope. Different tests help your doctor diagnose iron-deficiency anemia. In iron-deficiency anemia, blood ...

  19. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... for iron-deficiency anemia if you have certain risk factors , including pregnancy. To prevent iron-deficiency anemia, your doctor may recommend you eat heart-healthy foods or control other conditions that can cause iron-deficiency anemia. ...

  20. Iron and Your Child

    Science.gov (United States)

    ... deficiency isn't corrected, it can lead to iron-deficiency anemia (a decrease in the number of red blood ... Parents Kids Teens Anemia Blood Test: Ferritin (Iron) Iron-Deficiency Anemia Vegetarianism Menstrual Problems Pregnant or Breastfeeding? Nutrients You ...

  1. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... normally stores but has used up. Increase your intake of vitamin C to help your body absorb iron. Avoid drinking black tea, which reduces iron absorption. Other treatments If you have chronic kidney disease and iron-deficiency anemia, your doctor may recommend ...

  2. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... different ages and stages of life. Until the teen years, the recommended amount of iron is the ... cow’s milk. Cow’s milk is low in iron. Teens, who have increased need for iron during growth ...

  3. Precipitated iron. A limit on gettering efficacy in multicrystalline silicon

    Energy Technology Data Exchange (ETDEWEB)

    Fenning, D.P.; Hofstetter, J.; Bertoni, M.I.; Buonassisi, T. [Massachusetts Institute of Technology MIT, Cambridge, Massachusetts 02139 (United States); Coletti, G. [ECN Solar Energy, Westerduinweg 3, NL-1755 LE Petten (Netherlands); Lai, B. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Del Canizo, C. [Instituto de Energia Solar, Universidad Politecnica de Madrid, 28040 Madrid (Spain)

    2013-01-31

    A phosphorus diffusion gettering model is used to examine the efficacy of a standard gettering process on interstitial and precipitated iron in multicrystalline silicon. The model predicts a large concentration of precipitated iron remaining after standard gettering for most as-grown iron distributions. Although changes in the precipitated iron distribution are predicted to be small, the simulated post-processing interstitial iron concentration is predicted to depend strongly on the as-grown distribution of precipitates, indicating that precipitates must be considered as internal sources of contamination during processing. To inform and validate the model, the iron distributions before and after a standard phosphorus diffusion step are studied in samples from the bottom, middle, and top of an intentionally Fe-contaminated laboratory ingot. A census of iron-silicide precipitates taken by synchrotron-based X-ray fluorescence microscopy confirms the presence of a high density of iron-silicide precipitates both before and after phosphorus diffusion. A comparable precipitated iron distribution was measured in a sister wafer after hydrogenation during a firing step. The similar distributions of precipitated iron seen after each step in the solar cell process confirm that the effect of standard gettering on precipitated iron is strongly limited as predicted by simulation. Good agreement between the experimental and simulated data supports the hypothesis that gettering kinetics is governed by not only the total iron concentration but also by the distribution of precipitated iron. Finally, future directions based on the modeling are suggested for the improvement of effective minority carrier lifetime in multicrystalline silicon solar cells.

  4. Two modelling approaches to water-quality simulation in a flooded iron-ore mine (Saizerais, Lorraine, France): a semi-distributed chemical reactor model and a physically based distributed reactive transport pipe network model.

    Science.gov (United States)

    Hamm, V; Collon-Drouaillet, P; Fabriol, R

    2008-02-19

    The flooding of abandoned mines in the Lorraine Iron Basin (LIB) over the past 25 years has degraded the quality of the groundwater tapped for drinking water. High concentrations of dissolved sulphate have made the water unsuitable for human consumption. This problematic issue has led to the development of numerical tools to support water-resource management in mining contexts. Here we examine two modelling approaches using different numerical tools that we tested on the Saizerais flooded iron-ore mine (Lorraine, France). A first approach considers the Saizerais Mine as a network of two chemical reactors (NCR). The second approach is based on a physically distributed pipe network model (PNM) built with EPANET 2 software. This approach considers the mine as a network of pipes defined by their geometric and chemical parameters. Each reactor in the NCR model includes a detailed chemical model built to simulate quality evolution in the flooded mine water. However, in order to obtain a robust PNM, we simplified the detailed chemical model into a specific sulphate dissolution-precipitation model that is included as sulphate source/sink in both a NCR model and a pipe network model. Both the NCR model and the PNM, based on different numerical techniques, give good post-calibration agreement between the simulated and measured sulphate concentrations in the drinking-water well and overflow drift. The NCR model incorporating the detailed chemical model is useful when a detailed chemical behaviour at the overflow is needed. The PNM incorporating the simplified sulphate dissolution-precipitation model provides better information of the physics controlling the effect of flow and low flow zones, and the time of solid sulphate removal whereas the NCR model will underestimate clean-up time due to the complete mixing assumption. In conclusion, the detailed NCR model will give a first assessment of chemical processes at overflow, and in a second time, the PNM model will provide more

  5. Preparation, physical characterization, and stability of Ferrous-Chitosan microcapsules using different iron sources

    Science.gov (United States)

    Handayani, Noer Abyor; Luthfansyah, M.; Krisanti, Elsa; Kartohardjono, Sutrasno; Mulia, Kamarza

    2017-11-01

    Dietary modification, supplementation and food fortification are common strategies to alleviate iron deficiencies. Fortification of food is an effective long-term approach to improve iron status of populations. Fortification by adding iron directly to food will cause sensory problems and decrease its bioavailability. The purpose of iron encapsulation is: (1) to improve iron bioavailability, by preventing oxidation and contact with inhibitors and competitors; and (2) to disguise the rancid aroma and flavor of iron. A microcapsule formulation of two suitable iron compounds (iron II fumarate and iron II gluconate) using chitosan as a biodegradable polymer will be very important. Freeze dryer was also used for completing the iron microencapsulation process. The main objective of the present study was to prepare and characterize the iron-chitosan microcapsules. Physical characterization, i.e. encapsulation efficiency, iron loading capacity, and SEM, were also discussed in this paper. The stability of microencapsulated iron under simulated gastrointestinal conditions was also investigated, as well. Both iron sources were highly encapsulated, ranging from 71.5% to 98.5%. Furthermore, the highest ferrous fumarate and ferrous gluconate loaded were 1.9% and 4.8%, respectively. About 1.04% to 9.17% and 45.17% to 75.19% of Fe II and total Fe, were released in simulated gastric fluid for two hours and in simulated intestinal fluid for six hours, respectively.

  6. Prediction of porcine male fertility

    NARCIS (Netherlands)

    Broekhuijse, M.L.W.J.|info:eu-repo/dai/nl/313871728

    2012-01-01

    Life starts with fertilisation. Variation in fertility is caused by both farm and sow related parameters and boar and semen related parameters. Therefore, achieving high fertility is not obvious. Predominantly, artificial insemination (AI) is used for breeding pigs. The advantage of AI is that you

  7. Fertility treatment in obese women

    NARCIS (Netherlands)

    Koning, A.M.H.

    2015-01-01

    Overweight and obesity are increasing worldwide. This has major adverse consequences for health in general and fertility in women in particular. With the increasing number of women in reproductive age being obese, there is also an increasing need for fertility treatment. And with more pregnant women

  8. Fertility drugs and ovarian cancer.

    Science.gov (United States)

    Ali, Aus Tariq

    2017-06-20

    The aetiology of ovarian cancer is multifactorial with both endogenous and exogenous risk factors playing an important role. The exact pathogenesis of ovarian cancer is still not well understood, despite the number of hypotheses published. Due to an increase in the number of women using fertility drugs, much attention has been focused on the long-term health effects of such drugs. Although fertility drugs facilitate the ovulation process, it is however associated with a significant increase in hormone concentrations, placing exposed women at increased risk of gynaecological cancer. Many clinical and epidemiological studies have examined the association between fertility drugs and ovarian cancer risk. Results from these studies have been contradictory, as some studies have reported an increased risk of ovarian cancer while others reported no increased risk. Nevertheless, recent studies have shown that women who used fertility drugs and did not conceive had a higher risk of developing ovarian cancer, compared to women who used fertility drugs and conceived and delivered successfully. This review discusses the effect of fertility drugs on the risk of developing ovarian cancer, providing details on four possible scenarios associated with fertility treatment. In addition, the limitations of previous studies and their impact on our understanding of the association between fertility drugs and ovarian cancer also have been highlighted. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  9. Fertilizing Douglas-fir forests.

    Science.gov (United States)

    Richard E. Miller; Roger D. Right

    1979-01-01

    This report supplements a slide-tape presentation of the same title. Part I of the report describes the current practice of nitrogen fertilization of Douglas-fir forests in western Washington and Oregon and the effects of this fertilization on tree growth and water quality. Part II discusses factors that affect costs and revenues from investments in forest...

  10. Menstrual cycle pattern and fertility

    DEFF Research Database (Denmark)

    Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik

    1999-01-01

    To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss.......To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss....

  11. [Fertility and health in Mexico].

    Science.gov (United States)

    Urbina-Fuentes, M; Echánove-Fernández, E

    1989-01-01

    Fertility, health, and family planning are not independent factors, but rather involve a series of biological and social mechanisms in close interaction with one another. The impact that a high fertility rate has on health is reflected mainly in a rise in the rates of maternal and child mortality. Similarly, fertility has a greater negative effect upon the health of groups characterized by high reproductive risk, high parity, short intergenesic intervals, and unwanted pregnancies. On the other hand, family planning -and specifically the use of contraceptive methods-helps to achieve a lowering of the fertility rate and also has a positive effect on maternal-child health. This situation can be observed in the case of Mexico, where fertility rates and tendencies, as well as maternal and child mortality, have been reduced during the past decade.

  12. Isotope studies on rice fertilization

    International Nuclear Information System (INIS)

    1978-01-01

    The aim of the report is to provide practical information on the efficient utilization of nitrogen fertilizers in rice production. Results obtained from field investigations during the years 1970 to 1974 in ten countries (Bangladesh, Burma, Indonesia, Republic of Korea, Sri Lanka, Taiwan, Thailand, Vietnam, India, Philippines), using 15 N-labelled nitrogen fertilizers (ammonium sulfate, urea) are given. The experiments, which were conducted both during the dry and wet seasons, included comparison of varieties, effect of placement, source and time of nitrogen fertilizer application on the yield and quality of rice. The data from the project is presented in table form. In most of the experiments, the addition of nitrogen increased the rice grain yield. The role of soil nitrogen vs. fertilizer nitrogen is compared, and it is concluded that the physiological growth stage at which fertilizer-derived nitrogen is absorbed is of great importance

  13. Hyperfine interactions of iron implanted into aluminium

    International Nuclear Information System (INIS)

    Sawicka, B.D.; Drwiega, M.; Sawicki, J.; Stanek, J.

    1976-01-01

    Systematical investigations of the stable 57 Fe implanted into Al at energies of 10 to 70 keV and doses of 10 14 to 2.10 17 ions/cm 2 were performed by means of conversion electron Moessbauer spectroscopy at room and liquid nitrogen temperatures. The spectra measured were interpreted as originated by iron monomers (single line) and by iron associations, mostly dimers (dublet). The isomer shifts of both components differ considerably and are constant against iron concentration. The ratio of both components depends strongly on the iron concentration. The quadrupole splitting of the doublet rises with the concentration, the rise being reproduced by computer simulations of efg distributions in densely packed random charge defected lattices. The annealing processes were investigated. The spectra of the Fe-Al samples made by ion implantation and by a splat-cooling technique are well comparable. (author)

  14. Marketing Green Fertilizers: Insights into Consumer Preferences

    Directory of Open Access Journals (Sweden)

    Johannes Dahlin

    2016-11-01

    Full Text Available In an effort to support the long-term viability of the bioenergy industry through an end market for digestate, we investigated purchasing preferences for fertilizer product features in the home gardening market. We conducted a discrete choice experiment (DCE, presenting 504 respondents with a total of 6048 product attribute choices in a simulated context that replicated the tradeoff decisions made in the real marketplace. We analyzed the choice data using a hierarchical Bayes estimate to generate part-worth utilities for fertilizer product attributes. We then conducted a latent class analysis to identify market segments that could be expected to respond to differentiated product design strategies. We were able to quantify both purchasing preferences for fertilizer product attributes as well as the importance of each attribute to the perceived utility of a product. We were further able to identify five distinct market segments that make clear the potential for differentiated strategies in the home gardening market. We found both negative and positive price sensitivities, with sociodemographically distinct subgroups that favored low-, mid-, and high-priced products. We also found purchasing preferences for brand status, product labeling and nutrient values. Our results provide insights that should help product managers in the biogas industry develop marketing strategies to integrate digestate into a sustainable energy production system.

  15. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... options further? Fertility Preservation - Where Does It Fit? Options for Fertility Preservation The following diagram gives a brief description of fertility preservation options available to children diagnosed with cancer before and ...

  16. Synthesis and Stability of Iron Nanoparticles for Lunar Environment Studies

    Science.gov (United States)

    Hung, Ching-cheh; McNatt, Jeremiah

    2009-01-01

    Simulant of lunar dust is needed when researching the lunar environment. However, unlike the true lunar dust, today s simulants do not contain nanophase iron. Two different processes have been developed to fabricate nanophase iron to be used as part of the lunar dust simulant: (1) Sequentially treating a mixture of ferric chloride, fluorinated carbon, and soda lime glass beads at about 300 C in nitrogen, at room temperature in air, and then at 1050 C in nitrogen. The product includes glass beads that are grey in color, can be attracted by a magnet, and contain alpha-iron nanoparticles (which seem to slowly lose their lattice structure in ambient air during a period of 12 months). This product may have some similarity to the lunar glassy regolith that contains Fe(sup 0). (2) Heating a mixture of carbon black and a lunar simulant (a mixed metal oxide that includes iron oxide) at 1050 C in nitrogen. This process simulates lunar dust reaction to the carbon in a micrometeorite at the time of impact. The product contains a chemically modified simulant that can be attracted by a magnet and has a surface layer whose iron concentration increased during the reaction. The iron was found to be alpha-iron and Fe3O4 nanoparticles, which appear to grow after the fabrication process, but stabilizes after 6 months of ambient air storage.

  17. Fertilizers in cereals crops. Effect of fertilization in grain quality

    International Nuclear Information System (INIS)

    Melaj, Mariana

    1997-01-01

    In the last years the yields of the maize cultivation in the Pampeana production region have constantly increased, foreseeing higher increases of yield in the next years. Such increase is due, between other motives, to the use of hybrids of higher potential yield. There is a direct relation between the yield potential of a genotype and the nutrients demand, fact that constitutes one of the geneticists concerns. Maize hybrids reach its maximum expression when the plant is cultivated in good supplied soils with balanced quantities of nutrients that in several cases are reached with the practice of fertilization. The quantitative and qualitative vegetal response to the use of phosphate fertilizers depend of soils, of the environmental conditions, of fertilizer and the way of its application as well as of the maize hybrid that was used. To direct the practice of fertilization towards the reposition of the soil nutrients extracted by genotypes of high yield without producing excesses that increase costs and put in danger the environment, it is necessary to know the real coefficient used by the plants of the phosphorus available in the soils. The isotopic methodology allows to distinguish the phosphorus coming from two nutrient sources: soil and fertilizer, even in the juvenile phase of vegetal development and to evaluate the efficiency of fertilizers in plant nutrition. The objective of the present work was to evaluate the use of phosphorus coming from one of the phosphorus source available (soil, fertilizer), that should allow to increase and make more specific the knowledge's level of the different maize hybrids. This is obtained by determination of the grade of use of nutrient (of the soil) and of the nutrient of fertilizers, evaluating the qualitative and quantitative responses to fertilization

  18. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Ask Your Doctor Information for ...

  19. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Ask Your Doctor Information for Patients Many adult ...

  20. Comparison of unenriched versus 15N-enriched fertilizer as a tracer for N fertilizer uptake

    International Nuclear Information System (INIS)

    Meints, V.W.; Shearer, G.; Kohl, D.H.; Kurtz, L.T.

    1975-01-01

    A greenhouse experiment was conducted on three soils with differing cropping and fertilization histories to determine whether unenriched fertilizer N can be used in the same manner as 15 N-enriched fertilizer to estimate the amount of plant N derived from fertilizer. Estimates using unenriched fertilizer N were compared with estimates using two 15 N enrichment levels. Use of unenriched fertilizer N led to underestimation of the amount of fertilizer N in the plant material in four of six cases when compared to 15 N-enriched fertilizer. Standard deviations of the estimates of fertilizer-derived N in plant material were considerably greater when unenriched fertilizer was used. (U.S.)

  1. Zinc fertilization of flooded rice

    International Nuclear Information System (INIS)

    1981-02-01

    Local scientists studied Zn fertilization of flooded rice soils in Bangladesh, India, Indonesia, the Republic of Korea, Egypt, the Philippines, Thailand and Turkey. Diagnosis of Zn deficiency was carried out for submerged rice soils. Soil maps were prepared, designating areas as low, medium and high in Zn, based on Zn extraction with DTPA and HCl solutions and on rice leaf analysis. The effectiveness of various Zn fertilizer sources and methods of application in field and greenhouse experiments was measured, using 65 Zn. The percent Zn derived from fertilizer was shown to be a much more sensitive measure of efficiency than yield or total uptake

  2. Semen collection and fertility in naturally fertile sandhill cranes

    Science.gov (United States)

    Chen, G.; Gee, G.F.; Nicolich, Jane M.; Taylor, J.A.; Urbanek, R.P.; Stahlecker, D.W.

    1997-01-01

    Aviculturists often ask if semen collection will interfere with fertility in naturally fertile pairs of cranes. We used 12 naturally fertile Florida sandhill crane (Grus canadensis pratensis) pairs for this study, 6 control and 6 experimental. All pairs had produced fertile eggs in previous years and were in out-of-doors pens scattered throughout different pen complexes, within auditory range but physically isolated. Semen was collected on Tuesday mornings and Friday afternoons from 26 February 1993 to 4 June 1993. We used standard artificial insemination methods to collect and to evaluate the semen and spermatozoa. Semen collection did not affect semen quality or quantity. Semen volume, sperm density, sperm motility, sperm morphology, sperm live, sperm number per collection, and male response to semen collection exhibited significant daily variation (P semen collection began 13 days before the first egg in the experimental group, we observed no differences in the date of first egg laid or in fertility between experimental and control groups. Also, we observed no differences in the interval between clutches or in the percentage of broken eggs between experimental and control groups. Sires consistently producing better semen samples produced fewer fertile eggs than sires producing poorer semen samples (r = 0.60).

  3. Cellular iron transport.

    Science.gov (United States)

    Garrick, Michael D; Garrick, Laura M

    2009-05-01

    Iron has a split personality as an essential nutrient that also has the potential to generate reactive oxygen species. We discuss how different cell types within specific tissues manage this schizophrenia. The emphasis in enterocytes is on regulating the body's supply of iron by regulating transport into the blood stream. In developing red blood cells, adaptations in transport manage the body's highest flux of iron. Hepatocytes buffer the body's stock of iron. Macrophage recycle the iron from effete red cells among other iron management tasks. Pneumocytes provide a barrier to prevent illicit entry that, when at risk of breaching, leads to a need to handle the dangers in a fashion essentially shared with macrophage. We also discuss or introduce cell types including renal cells, neurons, other brain cells, and more where our ignorance, currently still vast, needs to be removed by future research.

  4. Iron Availability in Tropical Soils and Iron Uptake by Plants

    Directory of Open Access Journals (Sweden)

    Guilherme Furlan Mielki

    Full Text Available ABSTRACT Given the increase in crop yields and the expansion of agriculture in low fertility soils, deficiency of micronutrients, such as iron, in plants grown in tropical soils has been observed. The aim of this study was to evaluate Fe availability and Fe uptake by corn (Zea mays L. plants in 13 different soils, at two depths. Iron was extracted by Mehlich-1, Mehlich-3, and CaCl2 (Fe-CC and was fractionated in forms related to low (Feo and high (Fed crystallinity pedogenic oxyhydroxides, and organic matter (Fep using ammonium oxalate, dithionite-citrate, and sodium pyrophosphate, respectively. In order to relate Fe availability to soil properties and plant growth, an experiment was carried out in a semi-hydroponic system in which part of the roots developed in a nutrient solution (without Fe and part in the soil (the only source of Fe. Forty-five days after seeding, we quantified shoot dry matter and leaf Fe concentration and content. Fed levels were high, from 5 to 132 g kg-1, and Feo and Fe-CC levels were low, indicating the predominance of Fe as crystalline oxyhydroxides and a low content of Fe readily available to plants. The extraction solutions showed significant correlations with various soil properties, many common to both, indicating that they act similarly. The correlation between the Mehlich-1 and Mehlich-3 extraction solutions was highly significant. However, these two extraction methods were inefficient in predicting Fe availability to plants. There was a positive correlation between dry matter and Fe levels in plant shoots, even within the ranges considered adequate in the soil and in the plant. Dry matter production and leaf Fe concentration and content were positively correlated with Fep concentration, indicating that the Fe fraction related to soil organic matter most contributes to Fe availability to plants.

  5. Iron promotion of the TiO2 photosensitization process towards the photocatalytic oxidation of azo dyes under solar-simulated light irradiation

    International Nuclear Information System (INIS)

    Castro, Camilo A.; Centeno, Aristobulo; Giraldo, Sonia A.

    2011-01-01

    Highlights: → Azo dye photooxidation occurs under strict combination of ultraviolet and visible irradiation of Fe-TiO 2 . → Fe 3+ enhances the TiO 2 photooxidation of azo dyes while decreases that of phenol. → UV irradiation leads to a decrease in photooxidation activity of Fe-TiO 2 photocatalysts. - Abstract: The photocatalytic oxidation of the azo dye Orange-II (Or-II) using Fe loaded TiO 2 (Fe-TiO 2 ) was studied under ultraviolet (UV), visible (vis) and simultaneous UV-vis irradiations using a solar light simulator. Photocatalysts were characterized by means of XRD, SEM-EDX, FTIR and DRS. Fe 3+ species, identified in XPS analyses, were responsible of the increased absorption of visible light. Moreover, DRS analyses showed a decrease in the bandgap due to Fe 3+ loading. Photocatalystic tests proved that Fe modification enhanced the TiO 2 photocatalytic activity towards Or-II photodegradation under simultaneous UV-vis irradiation. Even so, the performance of the Fe-TiO 2 samples towards the photodegradation of phenol, under UV irradiation, was lower than TiO 2 suggesting the recombination of the UV photogenerated electron-hole pair. Therefore, results evidence a Fe 3+ promotion of the electron caption in the photosensitization process of TiO 2 by Or-II acting as a sensitizer. Such process leads to the Or-II photooxidation under UV-vis irradiation by losing energy in electron transferring processes to sensitize TiO 2 , and, the formation of reactive oxygen species promoted by the injected electron to the TiO 2 conduction band.

  6. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) programs. Our ... more information about Donor Iron Deficiency Study - Red Blood Cells ...

  7. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility ... injury? What is a Spinal Cord Injury? SCI Medical Experts People Living With SCI Personal Experiences By ...

  8. Determinants of fertility in Namibia

    African Journals Online (AJOL)

    AJRH Managing Editor

    This examines the fertility trends in Namibia over the past 2 decades .... contraceptive use was small because of the late age at first ..... limited flexibility in terms of maternity leave conditions ... Longer periods in education have increased the.

  9. In vivo fertilization of banana

    Directory of Open Access Journals (Sweden)

    Taliane Leila Soares

    2014-01-01

    Full Text Available The aim of this research was to study the in vivo fertilization process of banana cultivars. The diploid hybrid (AA 091087-01 was the male progenitor. Flower samples were checked for fertilization from the first to the twentieth day after pollination. The size of the diploid ovules increased gradually at the beginning of the seed formation process. On the other hand, in the AAA triploids (Cavendish subgroup, the not fertilized ovules were aborted. In the AAB triploids (Prata subgroup some ovules were fertilized. The flowers of Grand Naine, Nanicão and 'Pacovan' cultivars presented necrosis in the distal part of the ovary on the first day after pollination. Necrosis can hinder pollen tube growth towards the ovule, which might be related to the low seed yield in 'Pacovan' cultivars and to the absence of seeds in the Cavendish subgroup cultivars.

  10. Preserving Fertility while Battling Cancer

    Science.gov (United States)

    Some oncologists neglect to discuss the possibility of treatment-related infertility with patients of reproductive age. Researchers are developing decision aids to help patients make an informed, carefully considered decision about fertility.

  11. Determinants of fertility in Ethiopia

    African Journals Online (AJOL)

    be access to education, media, and providing employment opportunities in the modern economic sector. Besides .... and religion shows that muslim women have 1.7% high- er fertility ... traditional social and economic systems continue, the.

  12. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Topic Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury 101 David Chen, ...

  13. IVF-In Vitro Fertilization.

    Science.gov (United States)

    Kieffer, George H.

    1980-01-01

    Issues surrounding the controversial topic of in vitro fertilization and artificial manipulation of reproduction are discussed. The author examines the moral and ethical implications and presents results of a survey of various religious groups. (SA)

  14. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury ... 2525 info@facingdisability.com SIGN UP FOR OUR NEWSLETTER Your email address * This iframe contains the logic ...

  15. Is fertility falling in Zimbabwe?

    Science.gov (United States)

    Udjo, E O

    1996-01-01

    With an unequalled contraceptive prevalence rate in sub-Saharan Africa, of 43% among currently married women in Zimbabwe, the Central Statistical Office (1989) observed that fertility has declined sharply in recent years. Using data from several surveys on Zimbabwe, especially the birth histories of the Zimbabwe Demographic and Health Survey, this study examines fertility trends in Zimbabwe. The results show that the fertility decline in Zimbabwe is modest and that the decline is concentrated among high order births. Multivariate analysis did not show a statistically significant effect of contraception on fertility, partly because a high proportion of Zimbabwean women in the reproductive age group never use contraception due to prevailing pronatalist attitudes in the country.

  16. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Topic Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury 101 David ...

  17. (ajst) pedological characteristics, general fertility

    African Journals Online (AJOL)

    Administrator

    Key words: Pedological characteristics, fertility, soil classification, benchmark soils, Morogoro. District, Tanzania ... rigorous soil mapping to show their spatial distribution. Although at the ... experience bimodal rainfall pattern characterized by two .... evaluated based on the standards set by EUROCONSULT ... crop growth.

  18. Mineralogy and geochemistry of banded iron formation and iron ...

    Indian Academy of Sciences (India)

    The geological complexities of banded iron formation (BIF) and associated iron ores of Jilling–. Langalata iron ore ...... sure to sea water. Uranium in these samples varies ..... Ce oxidation and removal (Elderfield and Greaves. 1982; De Baar et ...

  19. Toxic diatoms and domoic acid in natural and iron enriched waters of the oceanic Pacific.

    Science.gov (United States)

    Silver, Mary W; Bargu, Sibel; Coale, Susan L; Benitez-Nelson, Claudia R; Garcia, Ana C; Roberts, Kathryn J; Sekula-Wood, Emily; Bruland, Kenneth W; Coale, Kenneth H

    2010-11-30

    Near-surface waters ranging from the Pacific subarctic (58°N) to the Southern Ocean (66°S) contain the neurotoxin domoic acid (DA), associated with the diatom Pseudo-nitzschia. Of the 35 stations sampled, including ones from historic iron fertilization experiments (SOFeX, IronEx II), we found Pseudo-nitzschia at 34 stations and DA measurable at 14 of the 26 stations analyzed for DA. Toxin ranged from 0.3 fg·cell(-1) to 2 pg·cell(-1), comparable with levels found in similar-sized cells from coastal waters. In the western subarctic, descent of intact Pseudo-nitzschia likely delivered significant amounts of toxin (up to 4 μg of DA·m(-2)·d(-1)) to underlying mesopelagic waters (150-500 m). By reexamining phytoplankton samples from SOFeX and IronEx II, we found substantial amounts of DA associated with Pseudo-nitzschia. Indeed, at SOFeX in the Antarctic Pacific, DA reached 220 ng·L(-1), levels at which animal mortalities have occurred on continental shelves. Iron ocean fertilization also occurs naturally and may have promoted blooms of these ubiquitous algae over previous glacial cycles during deposition of iron-rich aerosols. Thus, the neurotoxin DA occurs both in coastal and oceanic waters, and its concentration, associated with changes in Pseudo-nitzschia abundance, likely varies naturally with climate cycles, as well as with artificial iron fertilization. Given that iron fertilization in iron-depleted regions of the sea has been proposed to enhance phytoplankton growth and, thereby, both reduce atmospheric CO(2) and moderate ocean acidification in surface waters, consideration of the potentially serious ecosystem impacts associated with DA is prudent.

  20. Amorphous structure of iron oxide of bacterial origin

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Hideki; Fujii, Tatsuo [Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530 (Japan); Kohara, Shinji [Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198 (Japan); Asaoka, Hiroshi [Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530 (Japan); Kusano, Yoshihiro [Department of Fine and Applied Arts, Kurashiki University of Science and the Arts, Kurashiki, Okayama 712-8505 (Japan); Ikeda, Yasunori [Research Institute for Production Development, Sakyo-ku, Kyoto 606-0805 (Japan); Nakanishi, Makoto [Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530 (Japan); Benino, Yasuhiko; Nanba, Tokuro [Graduate School of Environmental Science, Okayama University, Okayama 700-8530 (Japan); Takada, Jun, E-mail: jtakada@cc.okayama-u.ac.jp [Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530 (Japan); JST, CREST, Okayama 700-8530 (Japan)

    2012-12-14

    In nature, there are various iron oxides produced by the water-habitant bacterial group called 'iron-oxidizing bacteria'. These iron oxides have been studied mainly from biological and geochemical perspectives. Today, attempts are made to use such iron oxides as novel functional materials in several applications. However, their quantitative structural characteristics are still unclear. We studied the structure of iron oxide of microtubular form consisting of amorphous nanoparticles formed by an iron-oxidizing bacterium, Leptothrix ochracea, using a combination of high-energy X-ray diffraction and reverse Monte Carlo simulation. We found that its structure consists of a framework of corner- and edge-sharing distorted FeO{sub 6} octahedral units, while SiO{sub 4} tetrahedral units are isolated in the framework. The results reveal the atomic arrangement of iron oxide of bacterial origin, which is essential for investigating its potential as a functional material. -- Highlights: Black-Right-Pointing-Pointer The amorphous structure of bacterial iron oxide was investigated. Black-Right-Pointing-Pointer The structure was simulated by high-energy X-ray diffraction and reverse Monte Carlo simulation. Black-Right-Pointing-Pointer The structure was constructed of a framework of corner- and edge-sharing distorted FeO{sub 6} octahedral units. Black-Right-Pointing-Pointer SiO{sub 4} tetrahedral units were distributed isolatedly in the framework of FeO{sub 6} octahedral units.

  1. Yield of castor bean fertilized with sewage sludge and potassium and magnesium sulphate

    Directory of Open Access Journals (Sweden)

    Thâmara F. M. Cavalcanti

    2015-08-01

    Full Text Available ABSTRACTThe aim of this study was to evaluate the yield and nutrition of castor bean in response to fertilization with sewage sludge and potassium (K and magnesium (Mg sulphate. The experiment was carried out from January to July 2011. The treatments, in a randomized block design with three replicates, in a Nitosol, corresponded to a factorial scheme (2 x 4 +1: two doses of K and Mg sulphate combined with four doses of sewage sludge (0, 2.60, 5.20 and 10.40 t ha-1, dry basis, applied based on its nitrogen (N content and the N requirement for the crop and an additional treatment with NPK. The castor bean grain yield fertilized with sewage sludge did not differ from conventional fertilization, with the maximum value achieved at a dose of 7.5 t ha-1 of sewage sludge. The fertilization with sewage sludge increased zinc and copper levels in the soil to values close to or higher than those in conventional fertilization, without any influence on the concentrations in the leaf. Fertilization with K and Mg sulphate increased the levels of these cations in the soil without affecting the concentrations in the leaves. The fertilization with sewage sludge increased the contents of organic matter, sulfur, zinc, iron, copper and boron in the soil, and manganese and boron in castor bean leaves.

  2. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... website. Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open ... Diagnosed with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation ...

  3. Fertility Preservation for Children Diagnosed with Cancer

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    Full Text Available ... Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu ... with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for ...

  4. Fertility Preservation for Children Diagnosed with Cancer

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    Full Text Available ... content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu Reprotopia_Main_Menu ... Cancer Fertility Preservation for Children Diagnosed with Cancer Patient Pocket Guides Patient Pocket Guides Patient Guides Fertility ...

  5. Iron Refractory Iron Deficiency Anaemia: A Rare Cause of Iron Deficiency Anaemia

    LENUS (Irish Health Repository)

    McGrath, T

    2018-01-01

    We describe the case of a 17-month-old boy with a hypochromic microcytic anaemia, refractory to oral iron treatment. After exclusion of dietary and gastrointestinal causes of iron deficiency, a genetic cause for iron deficiency was confirmed by finding two mutations in the TMPRSS6 gene, consistent with a diagnosis of iron-refractory iron deficiency anaemia (IRIDA).

  6. Fertility among female hairdressers.

    Science.gov (United States)

    Axmon, Anna; Rylander, Lars; Lillienberg, Linnea; Albin, Maria; Hagmar, Lars

    2006-02-01

    The study investigated whether working as a hairdresser has a negative impact on fertility, measured as time to pregnancy and miscarriage risk. Self-administered questionnaires were sent to 5289 Swedish hairdressers (response rate 50%) and to 5299 age-matched women from the general Swedish population (response rate 54%). Information was collected on time to pregnancy or trying time for women who had tried, but failed, to conceive at the time of the study. The outcome of the pregnancy was determined and categorized as either miscarriage or stillbirth or live birth. The hairdressers were compared with the referents with respect to these two outcomes. Within the hairdresser cohort, the effects of hair treatments, as well as physical workload and stress were investigated. The hairdressers were less successful than the reference cohort in conceiving (fecundability ratio 0.91, 95% confidence interval 0.83-0.99). The effect was reduced after first-month conceptions were excluded, the indication being that the effect may be the result of birth control bias. Within the hairdresser cohort, a self-perceived stressful work situation seemed to prolong the time to pregnancy. No effects were found for the different chemical hair treatments. There was no cohort difference with respect to miscarriage risk (odds ratio 1.12, 95% confidence interval 0.88-1.42), but miscarriage risks were increased for most of the hair treatments and for self-perceived stressful work situations. However, none of these effects were statistically significant. The present study indicates a negative impact on time to pregnancy and miscarriage risk for working as a hairdresser".

  7. Effect of long-term fertilization on humic redox mediators in multiple microbial redox reactions.

    Science.gov (United States)

    Guo, Peng; Zhang, Chunfang; Wang, Yi; Yu, Xinwei; Zhang, Zhichao; Zhang, Dongdong

    2018-03-01

    This study investigated the effects of different long-term fertilizations on humic substances (HSs), humic acids (HAs) and humins, functioning as redox mediators for various microbial redox biotransformations, including 2,2',4,4',5,5'- hexachlorobiphenyl (PCB 153 ) dechlorination, dissimilatory iron reduction, and nitrate reduction, and their electron-mediating natures. The redox activity of HSs for various microbial redox metabolisms was substantially enhanced by long-term application of organic fertilizer (pig manure). As a redox mediator, only humin extracted from soils with organic fertilizer amendment (OF-HM) maintained microbial PCB 153 dechlorination activity (1.03 μM PCB 153 removal), and corresponding HA (OF-HA) most effectively enhanced iron reduction and nitrate reduction by Shewanella putrefaciens. Electrochemical analysis confirmed the enhancement of their electron transfer capacity and redox properties. Fourier transform infrared analysis showed that C=C and C=O bonds, and carboxylic or phenolic groups in HSs might be the redox functional groups affected by fertilization. This research enhances our understanding of the influence of anthropogenic fertility on the biogeochemical cycling of elements and in situ remediation ability in agroecosystems through microorganisms' metabolisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Prevention of formation of acid drainage from high-sulfur coal refuse by inhibition of iron- and sulfur-oxidizing microorganisms. II. Inhibition in run of mine refuse under simulated field conditions

    Energy Technology Data Exchange (ETDEWEB)

    Dugan, P.R.

    1987-01-01

    The combination of sodium lauryl sulfate and benzoic acid effectively inhibits iron- and sulfur-oxidizing bacteria in coal refuse and prevents the conversion of iron pyrite to sulfate, ferric iron, and sulfuric acid, thereby significantly reducing the formation of acidic drainage from coal refuse. The inhibitors were effective in a concentration of 1.1. mg/kg refuse, and data indicate that the SLS was in excess of the concentration required. The treatment was compatible with the use of lime for neutralization of acid present prior to inhibition of its formation.

  9. Current understanding of iron homeostasis.

    Science.gov (United States)

    Anderson, Gregory J; Frazer, David M

    2017-12-01

    Iron is an essential trace element, but it is also toxic in excess, and thus mammals have developed elegant mechanisms for keeping both cellular and whole-body iron concentrations within the optimal physiologic range. In the diet, iron is either sequestered within heme or in various nonheme forms. Although the absorption of heme iron is poorly understood, nonheme iron is transported across the apical membrane of the intestinal enterocyte by divalent metal-ion transporter 1 (DMT1) and is exported into the circulation via ferroportin 1 (FPN1). Newly absorbed iron binds to plasma transferrin and is distributed around the body to sites of utilization with the erythroid marrow having particularly high iron requirements. Iron-loaded transferrin binds to transferrin receptor 1 on the surface of most body cells, and after endocytosis of the complex, iron enters the cytoplasm via DMT1 in the endosomal membrane. This iron can be used for metabolic functions, stored within cytosolic ferritin, or exported from the cell via FPN1. Cellular iron concentrations are modulated by the iron regulatory proteins (IRPs) IRP1 and IRP2. At the whole-body level, dietary iron absorption and iron export from the tissues into the plasma are regulated by the liver-derived peptide hepcidin. When tissue iron demands are high, hepcidin concentrations are low and vice versa. Too little or too much iron can have important clinical consequences. Most iron deficiency reflects an inadequate supply of iron in the diet, whereas iron excess is usually associated with hereditary disorders. These disorders include various forms of hemochromatosis, which are characterized by inadequate hepcidin production and, thus, increased dietary iron intake, and iron-loading anemias whereby both increased iron absorption and transfusion therapy contribute to the iron overload. Despite major recent advances, much remains to be learned about iron physiology and pathophysiology. © 2017 American Society for Nutrition.

  10. Uranium and heavy metals in phosphate fertilizers

    International Nuclear Information System (INIS)

    Khater, Ashraf E.M.; King Saud University, Riyadh

    2008-01-01

    Full text: Agricultural applications of chemical fertilizers are a worldwide practice. The specific activity of uranium-238 and heavy metals in phosphate fertilizers depends on the phosphate ore from which the fertilizer produced and on the chemical processing of the ore. Composite phosphate fertilizers samples were collected and the uranium-238 specific activity, in Bq/kg, and As, Cd, Cu, Pb, Se concentration were measured. The annual addition of these elements in soil due to soil fertilization were calculated and discussed. (author)

  11. Iron-Deficiency Anemia

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    Full Text Available ... exploring about iron-deficiency anemia. Read more New treatments for disorders that lead to iron-deficiency anemia. We are ... and other pathways. This could help develop new therapies for conditions that ... behavior, thinking, and mood during adolescence. Treating anemia in ...

  12. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... grams per deciliter (g/dl) for men and less than 12 g/dl for women is diagnostic of anemia. In iron-deficiency anemia, ... blood levels of iron will be low, or less than 10 micromoles per liter (mmol/L) for both men and women. Normal levels are 10 to 30 mmol/L. ...

  13. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... is blood loss during dialysis. People who have chronic kidney disease also often take other medicines—such as proton ... reduces iron absorption. Other treatments If you have chronic kidney disease and iron-deficiency anemia, your doctor may recommend ...

  14. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... loss and lead to iron-deficiency anemia. Common causes of blood loss that lead to iron-deficiency anemia include: Bleeding in your GI tract, from an ulcer, colon cancer, or regular use of medicines such as aspirin ...

  15. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... ages and stages of life. Until the teen years, the recommended amount of iron is the same for boys and girls. From birth to 6 months, babies need 0.27 mg of iron. This number goes up to 11 mg for children ages 7 to 12 months, and down to 7 mg for children ...

  16. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... have less hemoglobin than normal. Hemoglobin is a protein inside red blood cells that carries oxygen from the lungs to tissues ... stored iron has been used. Ferritin is a protein that helps store iron in your ... very young red blood cells. Peripheral smear to see if your red blood ...

  17. Iron-Deficiency Anemia

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    Full Text Available ... iron supplements work best to treat iron-deficiency anemia in children who do not consume the daily recommended amount ... and Clinical Studies to hear experts, parents, and children talk about their experiences with clinical ... Anemia Arrhythmia Blood Donation Blood Tests Blood ...

  18. Iron-Deficiency Anemia

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    Full Text Available ... iron-deficiency anemia. Search the NIH Research Portfolio Online Reporting Tools (RePORT) to learn about research that ... iron-deficiency anemia in blood donors affects the quality of donated red blood cells, such as how ...

  19. Iron-Deficiency Anemia

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    Full Text Available ... or oral iron, by mouth once or several times a day to increase the iron in your body. This is ... and newer recommendations to increase the length of time between donations to protect blood donors. Cardiovascular Health Study identifies predictors ...

  20. Iron-Deficiency Anemia

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    Full Text Available ... or oral iron, by mouth once or several times a day to increase the iron in your body. This is the most common treatment ... and newer recommendations to increase the length of time between donations to protect ... in older adults. The NHLBI-sponsored Cardiovascular Health Study ...

  1. Iron deficiency in children

    African Journals Online (AJOL)

    cell and excess iron is stored as ferritin to protect the cell from oxidative ... iron deficiency has negative effects during pregnancy and in the postpartum period, which affects maternal health ... use of undiluted cow's milk and a predominant cow's milk intake in .... on bone marrow smear or biopsy for the definitive diagnosis of.

  2. Iron-Deficiency Anemia

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    Full Text Available ... Certain conditions or medicines can decrease your body’s ability to absorb iron and lead to iron-deficiency ... environment or water. Lead interferes with the body’s ability to make hemoglobin. Family history and genetics Von ...

  3. Iron-Deficiency Anemia

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    Full Text Available ... anemia if you have certain risk factors , including pregnancy. To prevent iron-deficiency anemia, your doctor may recommend you eat heart-healthy foods or control other conditions that can cause iron-deficiency anemia. Blood tests to screen for ...

  4. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Services’ National Institutes of Health (NIH)—the Nation’s biomedical research agency that makes important scientific discoveries to improve ... efforts for iron-deficiency anemia. Learn about exciting research areas that ... This could help develop new therapies for conditions that affect the balance of iron ...

  5. Iron-Deficiency Anemia

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    Full Text Available ... Are you curious about how inflammation from chronic diseases can cause iron-deficiency anemia? Read more When there is ... DBDR) is a leader in research on the causes, prevention, and treatment of blood diseases, including iron-deficiency anemia. Search the NIH Research ...

  6. Iron-Deficiency Anemia

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    Full Text Available ... the Eunice Kennedy Shriver National Institute of Child Health and Human Development, we are investigating how best to treat premature newborns with low hemoglobin levels. We also are hoping to determine which iron supplements work best to treat iron-deficiency anemia in children ...

  7. Iron-Deficiency Anemia

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    Full Text Available ... do not have enough iron in your body. People with mild or moderate iron-deficiency anemia may ... as a TMRPSS6 gene mutation that causes a person’s body to make too much of a hormone ...

  8. Iron-Deficiency Anemia

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    Full Text Available ... during the third trimester of pregnancy. Children between ages 1 and 2, especially if they drink a lot of cow’s milk. Cow’s milk is low in iron. Teens, who have increased need for iron during growth spurts. Older adults, especially those ... environments Children who have lead in ...

  9. Iron-Deficiency Anemia

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    Full Text Available ... anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, such as meat and fish, may result in ... deficiency anemia, your doctor may recommend heart-healthy eating and choosing iron-rich foods, especially during certain stages of life when more ...

  10. [Iron deficiency and pica].

    Science.gov (United States)

    Muñoz, J A; Marcos, J; Risueño, C E; de Cos, C; López, R; Capote, F J; Martín, M V; Gil, J L

    1998-02-01

    To study the relationship between pica and iron-lack anaemia in a series of iron-deficiency patients in order to establish the pathogenesis of such relationship. Four-hundred and thirty-three patients were analysed. Pica was studied by introducing certain diet queries into the clinical history. All patients received oral iron and were periodically controlled with the usual clinico-haematological procedures. Pica was present in 23 patients (5.3%). Eight nourishing (namely, coffee grains, almonds, chocolate, ice, lettuce, carrots, sunflower seeds and bread) and 2 non-nourishing (clay and paper) substances were involved. A second episode of pica appeared in 9 cases upon relapsing of iron deficiency. Both anaemia and pica were cured by etiologic and substitutive therapy in all instances. No clear correlation was found with either socio-economic status or pathogenetic causes of iron deficiency and pica, and no haematological differences were seen between patients with pica and those without this alteration. (1) The pathogenesis of pica is unclear, although it appears unrelated to the degree of iron deficiency. (2) According to the findings in this series, pica seems a consequence of iron deficiency rather than its cause. (3) Adequate therapy can cure both conditions, although pica may reappear upon relapse of iron deficiency.

  11. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... stores are developed during the third trimester of pregnancy. Children between ages 1 and 2, especially if they drink a lot of cow’s milk. Cow’s milk is low in iron. Teens, who have increased need for iron during growth ...

  12. Iron-Deficiency Anemia

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    Full Text Available ... other conditions that can cause iron-deficiency anemia. Blood tests to screen for iron-deficiency anemia To screen ... check the size of your liver and spleen. Blood tests Based on results from blood tests to screen ...

  13. Iron-Deficiency Anemia

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    Full Text Available ... en español Iron-deficiency anemia is a common type of anemia that occurs if you do not ... iron-deficiency anemia and help rule out other types of anemia. Treatment will explain treatment-related complications ...

  14. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... with the Eunice Kennedy Shriver National Institute of Child Health and Human Development, we are investigating how best to treat premature newborns with low hemoglobin levels. We also are hoping to determine which iron supplements work best to treat iron-deficiency anemia in children ...

  15. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Precision Medicine Activities Obesity, Nutrition, and Physical Activity Population and Epidemiology Studies Women’s Health All Science A- ... to help your body absorb iron. Avoid drinking black tea, which reduces iron ... was associated with a greater risk of death even with mild anemia. Now, anemia in older ...

  16. Iron deficiency in childhood

    NARCIS (Netherlands)

    Uijterschout, L.

    2015-01-01

    Iron deficiency (ID) is the most common micronutrient deficiency in the world. Iron is involved in oxygen transport, energy metabolism, immune response, and plays an important role in brain development. In infancy, ID is associated with adverse effects on cognitive, motor, and behavioral development

  17. Iron-Deficiency Anemia

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    Full Text Available ... anemia. Return to Signs, Symptoms, and Complications to review signs and symptoms as well as complications from iron-deficiency ... NIH]) Heavy Menstrual Bleeding (Centers for Disease Control and ... Dietary Supplement Fact Sheet (NIH) Iron-Deficiency Anemia (National Library ...

  18. Iron-Deficiency Anemia

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    Full Text Available ... be at risk for iron-deficiency anemia. Lifestyle habits Certain lifestyle habits may increase your risk for iron-deficiency anemia, ... you are experiencing side effects such as a bad metallic taste, vomiting, diarrhea, constipation, or upset stomach. ...

  19. Iron-Deficiency Anemia

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    Full Text Available ... age, sex, and whether you are pregnant or breastfeeding. Recommended daily iron intake for children and adults. The table lists the recommended amounts of iron, in milligrams (mg) at different ages and stages of life. Until the teen years, the recommended amount of ...

  20. Iron-Deficiency Anemia

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    Full Text Available ... how we are using current research and advancing research to prevent iron-deficiency anemia. Participate in NHLBI Clinical Trials will explain our ongoing clinical studies that are investigating prevention strategies for iron-deficiency anemia. Signs, Symptoms, and Complications ...

  1. Patriarchy and fertility in Albania

    Directory of Open Access Journals (Sweden)

    Mathias Lerch

    2013-07-01

    Full Text Available BACKGROUND Theories of fertility collapse in the post-socialist era imply a decline in the moral primacy of traditional social institutions. Yet gender inequality actually increased in many countries, and there is a scarcity of empirical evidence for the role played by traditional social institutions in reproductive decision-making. OBJECTIVE We investigate whether patriarchal institutions sustained the fertility levels in Albania. The geography of marriage and family enlargement is related to the importance of patriarchy in kinship organisation and in the public sphere. To account for this spatial relationship we test the evidence for different pathways in patriarchal influence on reproductive decision-making including social effects, socialisation in patriarchal ideals, and the promotion of male fertility. METHODS We reconstruct reproductive histories from the 2001 Census and use data on attitudes and fertility intentions from the Reproductive and Health Survey 2002. Multilevel logistic regressions on marriage and (the intention of higher order births are used. RESULTS A majority of women endorsed patriarchal ideals and fertility transition was less advanced in more patriarchal municipalities. Patriarchal kinship organisation promoted early marriages and high fertility, which is shown to be achieved by social learning among peers and intergenerational social influences respectively, as well as by women's socialisation and a stopping behaviour in childbearing dominated by son-preference. Although gender inequality in the public sphere has also sustained the level of fertility and decreased the risk of marriage, it was not accounted for by these pathways of patriarchal influence. CONCLUSIONS Despite Albania's gradual opening to the world in a period of economic and political crisis, traditional social institutions remain important for family behaviours.

  2. Iron replacement therapy

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Coskun, Mehmet; Weiss, Günter

    2016-01-01

    PURPOSE OF REVIEW: Approximately, one-third of the world's population suffers from anemia, and at least half of these cases are because of iron deficiency. With the introduction of new intravenous iron preparations over the last decade, uncertainty has arisen when these compounds should...... be administered and under which circumstances oral therapy is still an appropriate and effective treatment. RECENT FINDINGS: Numerous guidelines are available, but none go into detail about therapeutic start and end points or how iron-deficiency anemia should be best treated depending on the underlying cause...... of iron deficiency or in regard to concomitant underlying or additional diseases. SUMMARY: The study points to major issues to be considered in revisions of future guidelines for the true optimal iron replacement therapy, including how to assess the need for treatment, when to start and when to stop...

  3. AN APPROACH FOR TECHNOLOGICAL MANAGEMENT OF MINERAL FERTILIZATION OF CROPS

    Directory of Open Access Journals (Sweden)

    ATANAS Atanasov

    2008-07-01

    Full Text Available An approach for technological management of mineral fertilization in crops based on simulation was presented. The simulation of the interaction between technical means, agricultural workers, crops, soils and fi elds was based on step of the algorithm. It included the following main steps: calculation of the adequate rate of fertilizers depending on soil reserves and the crop requirements, computing the number of aggregates depending of the duration of work, calculation of the productivity of machines, determination of the optimal duration of work and the number of aggregates depending on the shift duration. The new approach presented enabled the following: optimization of time for actual use of the resources, within the boundaries of the agrothechnical terms; precisely simulation of the initial data; specifying the decision for the concrete conditions; easy accessibility and applicability for a broad range of users.

  4. The economics of fertility.

    Science.gov (United States)

    Loraine, J A

    1982-01-01

    The statement that economics and fertility are closely interrelated is a truism. The classical economists--Adam Smith, Thomas Malthus, Karl Marx, John Stuart Mill and John Maynard Keynes appreciated this fact, and their reviews are recounted and their prescience is assessed. Adam Smith (1723-1790) was primarily concerned with the desire of humankind to better his/her material conditions. Although he did not put forward a specific population policy, the tenet of his writing is pronatalist. Economic advantages would accrue to parents by the production of many children. Yet, underneath Smith's optimism, there was an apocalyptic vision of the distant future, i.e., the "steady state" when resources would be depleted or near exhaustion, when capital accumulation would have ceased, and living standards would be dropping vertiginously. In his 1st "Essay on Population" Malthus maintained that "the power of population is infinitely greater than the power of the earth to produce subsistence of men." Malthus can be complimented on his prescience. There is little question that the planet of today is grossly overpopulated and that a great gulf exists between numbers of people and their aspirations and the resources which the earth can provide for them. Malthus was particularly concerned about the population food dilemma, and that is still much in evidence in 1982. 2 concomitants of overpopulation--excessive urbanization and joblessness--could not be foreseen by Malthus. Marx did not deny the basic tenet promulgated by Malthus but to him this was simply an artifact of capitalist society which required "enormous reserves of proletarians" in order to maintain its odius system. Officially Communist governments remain in a Marxist straitjacket regarding the population issue. Mills approach was strongly antinatalist; he saw little need for an increase in human numbers. Mills was concerned that because of unlimited population growth and wealth the earth would lose much of its

  5. Characterization of Prochlorococcus clades from iron-depleted oceanic regions.

    Science.gov (United States)

    Rusch, Douglas B; Martiny, Adam C; Dupont, Christopher L; Halpern, Aaron L; Venter, J Craig

    2010-09-14

    Prochlorococcus describes a diverse and abundant genus of marine photosynthetic microbes. It is primarily found in oligotrophic waters across the globe and plays a crucial role in energy and nutrient cycling in the ocean ecosystem. The abundance, global distribution, and availability of isolates make Prochlorococcus a model system for understanding marine microbial diversity and biogeochemical cycling. Analysis of 73 metagenomic samples from the Global Ocean Sampling expedition acquired in the Atlantic, Pacific, and Indian Oceans revealed the presence of two uncharacterized Prochlorococcus clades. A phylogenetic analysis using six different genetic markers places the clades close to known lineages adapted to high-light environments. The two uncharacterized clades consistently cooccur and dominate the surface waters of high-temperature, macronutrient-replete, and low-iron regions of the Eastern Equatorial Pacific upwelling and the tropical Indian Ocean. They are genetically distinct from each other and other high-light Prochlorococcus isolates and likely define a previously unrecognized ecotype. Our detailed genomic analysis indicates that these clades comprise organisms that are adapted to iron-depleted environments by reducing their iron quota through the loss of several iron-containing proteins that likely function as electron sinks in the photosynthetic pathway in other Prochlorococcus clades from high-light environments. The presence and inferred physiology of these clades may explain why Prochlorococcus populations from iron-depleted regions do not respond to iron fertilization experiments and further expand our understanding of how phytoplankton adapt to variations in nutrient availability in the ocean.

  6. Both Phosphorus Fertilizers and Indigenous Bacteria Enhance Arsenic Release into Groundwater in Arsenic-Contaminated Aquifers.

    Science.gov (United States)

    Lin, Tzu-Yu; Wei, Chia-Cheng; Huang, Chi-Wei; Chang, Chun-Han; Hsu, Fu-Lan; Liao, Vivian Hsiu-Chuan

    2016-03-23

    Arsenic (As) is a human carcinogen, and arsenic contamination in groundwater is a worldwide public health concern. Arsenic-affected areas are found in many places but are reported mostly in agricultural farmlands, yet the interaction of fertilizers, microorganisms, and arsenic mobilization in arsenic-contaminated aquifers remains uncharacterized. This study investigates the effects of fertilizers and bacteria on the mobilization of arsenic in two arsenic-contaminated aquifers. We performed microcosm experiments using arsenic-contaminated sediments and amended with inorganic nitrogenous or phosphorus fertilizers for 1 and 4 months under aerobic and anaerobic conditions. The results show that microcosms amended with 100 mg/L phosphorus fertilizers (dipotassium phosphate), but not nitrogenous fertilizers (ammonium sulfate), significantly increase aqueous As(III) release in arsenic-contaminated sediments under anaerobic condition. We also show that concentrations of iron, manganese, potassium, sodium, calcium, and magnesium are increased in the aqueous phase and that the addition of dipotassium phosphate causes a further increase in aqueous iron, potassium, and sodium, suggesting that multiple metal elements may take part in the arsenic release process. Furthermore, microbial analysis indicates that the dominant microbial phylum is shifted from α-proteobacteria to β- and γ-proteobacteria when the As(III) is increased and phosphate is added in the aquifer. Our results provide evidence that both phosphorus fertilizers and microorganisms can mediate the release of arsenic to groundwater in arsenic-contaminated sediments under anaerobic condition. Our study suggests that agricultural activity such as the use of fertilizers and monitoring phosphate concentration in groundwater should be taken into consideration for the management of arsenic in groundwater.

  7. Male fertility in cystic fibrosis.

    LENUS (Irish Health Repository)

    Chotirmall, S H

    2011-04-05

    Infertility rates among males with cystic fibrosis (CF) approximate 97%. No information is currently available within Ireland determining an understanding of fertility issues and the best methods of information provision to this specialized group. This study aimed to determine understanding and preferred approaches to information provision on fertility issues to Irish CF males. A Descriptive Study utilizing prospective coded questionnaires was mailed to a male CF cohort (n=50). Sections included demographics, fertility knowledge & investigation. Response rate was 16\\/50 (32%). All were aware that CF affected their fertility. More than two-thirds (n=11) were able to provide explanations whilst only one-third (n=5) provided the correct explanation. Significant numbers stated thoughts of marriage and a future family. Half have discussed fertility with a healthcare professional (HCP). Mean age of discussion was 21.9 years. One third preferred an earlier discussion. The commonest first source for information was written material which was also the preferred source. Three-quarters requested further information preferring again, written material. Significant gaps in sex education of Irish CF males exist. Discussion should be initiated by HCPs and centre-directed written material devised to address deficiencies.

  8. Obesity: modern man's fertility nemesis.

    Science.gov (United States)

    Cabler, Stephanie; Agarwal, Ashok; Flint, Margot; du Plessis, Stefan S

    2010-07-01

    The obesity pandemic has grown to concerning proportions in recent years, not only in the Western World, but in developing countries as well. The corresponding decrease in male fertility and fecundity may be explained in parallel to obesity, and obesity should be considered as an etiology of male fertility. Studies show that obesity contributes to infertility by reducing semen quality, changing sperm proteomes, contributing to erectile dysfunction, and inducing other physical problems related to obesity. Mechanisms for explaining the effect of obesity on male infertility include abnormal reproductive hormone levels, an increased release of adipose-derived hormones and adipokines associated with obesity, and other physical problems including sleep apnea and increased scrotal temperatures. Recently, genetic factors and markers for an obesity-related infertility have been discovered and may explain the difference between fertile obese and infertile obese men. Treatments are available for not only infertility related to obesity, but also as a treatment for the other comorbidities arising from obesity. Natural weight loss, as well as bariatric surgery are options for obese patients and have shown promising results in restoring fertility and normal hormonal profiles. Therapeutic interventions including aromatase inhibitors, exogenous testosterone replacement therapy and maintenance and regulation of adipose-derived hormones, particularly leptin, may also be able to restore fertility in obese males. Because of the relative unawareness and lack of research in this area, controlled studies should be undertaken and more focus should be given to obesity as an etiolgy of male infertility.

  9. Fertility preservation in Turner syndrome.

    Science.gov (United States)

    Grynberg, Michaël; Bidet, Maud; Benard, Julie; Poulain, Marine; Sonigo, Charlotte; Cédrin-Durnerin, Isabelle; Polak, Michel

    2016-01-01

    Premature ovarian insufficiency is a relatively rare condition that can appear early in life. In a non-negligible number of cases the ovarian dysfunction results from genetic diseases. Turner syndrome (TS), the most common sex chromosome abnormality in females, is associated with an inevitable premature exhaustion of the follicular stockpile. The possible or probable infertility is a major concern for TS patients and their parents, and physicians are often asked about possible options to preserve fertility. Unfortunately, there are no recommendations on fertility preservation in this group. The severely reduced follicle pool even during prepubertal life represents the major limit for fertility preservation and is the root of numerous questions regarding the competence of gametes or ovarian tissue crybanked. In addition, patients suffering from TS show higher than usual rates of spontaneous abortion, fetal anomaly, and maternal morbidity and mortality, which should be considered at the time of fertility preservation and before reutilization of the cryopreserved gametes. Apart from fulfillment of the desire of becoming genetic parents, TS patients may be potential candidates for egg donation, gestational surrogacy, and adoption. The present review discusses the different options for preserving female fertility in TS and the ethical questions raised by these approaches. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  10. Role of glutaredoxin 3 in iron homeostasis

    Science.gov (United States)

    Iron is an essential mineral nutrient that is tightly regulated through mechanisms involving iron regulatory genes, intracellular storage, and iron recycling. Dysregulation of these mechanisms often results in either excess tissue iron accumulation (overload) or iron deficiency (anemia). Many bioche...

  11. Laboratory Simulations of Micrometeoroid Ablation

    Science.gov (United States)

    Thomas, Evan Williamson

    Each day, several tons of meteoric material enters Earth's atmosphere, the majority of which consist of small dust particles (micrometeoroids) that completely ablate at high altitudes. The dust input has been suggested to play a role in a variety of phenomena including: layers of metal atoms and ions, nucleation of noctilucent clouds, effects on stratospheric aerosols and ozone chemistry, and the fertilization of the ocean with bio-available iron. Furthermore, a correct understanding of the dust input to the Earth provides constraints on inner solar system dust models. Various methods are used to measure the dust input to the Earth including satellite detectors, radar, lidar, rocket-borne detectors, ice core and deep-sea sediment analysis. However, the best way to interpret each of these measurements is uncertain, which leads to large uncertainties in the total dust input. To better understand the ablation process, and thereby reduce uncertainties in micrometeoroid ablation measurements, a facility has been developed to simulate the ablation of micrometeoroids in laboratory conditions. An electrostatic dust accelerator is used to accelerate iron particles to relevant meteoric velocities (10-70 km/s). The particles are then introduced into a chamber pressurized with a target gas, and they partially or completely ablate over a short distance. An array of diagnostics then measure, with timing and spatial resolution, the charge and light that is generated in the ablation process. In this thesis, we present results from the newly developed ablation facility. The ionization coefficient, an important parameter for interpreting meteor radar measurements, is measured for various target gases. Furthermore, experimental ablation measurements are compared to predictions from commonly used ablation models. In light of these measurements, implications to the broader context of meteor ablation are discussed.

  12. Liver Iron Contents in Rats after Administration of Certain Iron ...

    African Journals Online (AJOL)

    The effect of consumption of certain iron compounds on liver iron deposition was ... extra iron probably depends on the type of food prepared, .... main groups. Each main group consisted of 4 subgroups. (8 rats per subgroup) which received the same basic diet but differing amounts of iron of a specific type. Each animal was ...

  13. Fertility effects of cancer treatment.

    Science.gov (United States)

    Marsden, Donald E; Hacker, Neville

    2003-01-01

    Cancer sufferers are a subfertile group, and most treatments have the potential to adversely affect gonadal function. As cancer treatment becomes more effective and survival rates improve there are more cancer survivors in the reproductive age group for whom parenting is an important consideration. This article outlines the effects on fertility of cancer treatments and techniques to minimise the risk of infertility. The overall prospects for younger cancer sufferers to either retain their fertility or have genetic offspring is now better than ever before, due to advances in assisted reproductive technology, the appropriate use of fertility sparing surgery and other techniques to reduce the toxicity of therapy on the reproductive organs. These advances raise new moral and ethical concerns that must be considered before advising cancer sufferers of the options for preserving reproductive capacity.

  14. Crystallographic properties of fertilizer compounds

    Energy Technology Data Exchange (ETDEWEB)

    Frazier, A.W.; Dillard, E.F.; Thrasher, R.D.; Waerstad, K.R.; Hunter, S.R.; Kohler, J.J.; Scheib, R.M.

    1991-02-01

    This bulletin is a compilation of crystallographic data collected at NFERC on 450 fertilizer-related compounds. In TVA's fertilizer R and D program, petrographic examination, XRD, and infrared spectroscopy are combined with conventional chemical analysis methods in identifying the individual compounds that occur in fertilizer materials. This handbook brings together the results of these characterization studies and supplemental crystallographic data from the literature. It is in one-compound-per-page, loose-leaf format, ordered alphabetically by IUPAC name. Indexes provided include IUPAC name, formula, group, alternate formula, synonyms, x-ray data, optical data. Tables are given for solids, compounds in commercial MAP and DAP, and matrix materials in phosphate rock.

  15. Experimental Investigation on Corrosion of Cast Iron Pipes

    Directory of Open Access Journals (Sweden)

    H. Mohebbi

    2011-01-01

    Full Text Available It is well known that corrosion is the predominant mechanism for the deterioration of cast iron pipes, leading to the reduction of pipe capacity and ultimate collapse of the pipes. In order to assess the remaining service life of corroded cast iron pipes, it is imperative to understand the mechanisms of corrosion over a long term and to develop models for pipe deterioration. Although many studies have been carried out to determine the corrosion behavior of cast iron, little research has been undertaken to understand how cast iron pipes behave over a longer time scale than hours, days, or weeks. The present paper intends to fill the gap regarding the long-term corrosion behaviour of cast iron pipes in the absence of historical data. In this paper, a comprehensive experimental program is presented in which the corrosion behaviour of three exservice pipes was thoroughly examined in three simulated service environments. It has been found in the paper that localised corrosion is the primary form of corrosion of cast iron water pipes. It has also been found that the microstructure of cast irons is a key factor that affects the corrosion behaviour of cast iron pipes. The paper concludes that long-term tests on corrosion behaviour of cast iron pipes can help develop models for corrosion-induced deterioration of the pipes for use in predicting the remaining service life of the pipes.

  16. The Heterotrophic Bacterial Response During the Meso-scale Southern Ocean Iron Experiment (SOFeX)

    Science.gov (United States)

    Oliver, J. L.; Barber, R. T.; Ducklow, H. W.

    2002-12-01

    Previous meso-scale iron enrichments have demonstrated the stimulatory effect of iron on primary productivity and the accelerated flow of carbon into the surface ocean foodweb. In stratified waters, heterotrophic activity can work against carbon export by remineralizing POC and/or DOC back to CO2, effectively slowing the biological pump. To assess the response of heterotrophic activity to iron enrichment, we measured heterotrophic bacterial production and abundance during the Southern Ocean Iron Experiment (SOFeX). Heterotrophic bacterial processes primarily affect the latter of the two carbon export mechanisms, removal of DOC to the deep ocean. Heterotrophic bacterial production (BP), measured via tritiated thymidine (3H-TdR) and leucine (3H-Leu) incorporation, increased ~40% over the 18-d observation period in iron fertilized waters south of the Polar Front (South Patch). Also, South Patch BP was 61% higher than in the surrounding unfertilized waters. Abundance, measured by flow cytometry (FCM) and acridine orange direct counts (AODC), also increased in the South Patch from 3 to 5 x 108 cells liter-1, a 70% increase. Bacterial biomass increased from ~3.6 to 6.3 μg C liter-1, a clear indication that production rates exceeded removal rates (bactivory, viral lysis) over the course of 18 days. Biomass within the fertilized patch was 11% higher than in surrounding unfertilized waters reflecting a similar trend. This pattern is in contrast to SOIREE where no accumulation of biomass was observed. High DNA-containing (HDNA) cells detected by FCM also increased over time in iron fertilized waters from 20% to 46% relative to the total population suggesting an active subpopulation of cells that were growing faster than the removal rates. In iron fertilized waters north of the Polar Front (North Patch), BP and abundance were ~90% and 80% higher, respectively, than in unfertilized waters. Our results suggest an active bacterial population that responded to iron fertilization

  17. Fertility and apparent genetic anticipation in Lynch syndrome.

    Science.gov (United States)

    Stupart, Douglas; Win, Aung Ko; Jenkins, Mark; Winship, Ingrid M; Goldberg, Paul; Ramesar, Rajkumar

    2014-09-01

    Genetic anticipation is the phenomenon in which age of onset of an inherited disorder decreases in successive generations. Inconsistent evidence suggests that this occurs in Lynch syndrome. A possible cause for apparent anticipation is fecundity bias, which occurs if the disease adversely affects fertility. The purpose of this study was to determine the effect of age of diagnosis of colorectal cancer (CRC) on lifetime fertility in Lynch syndrome, and whether this can falsely create the appearance of genetic anticipation. A computer model simulated age of diagnosis of CRC in hypothetical Lynch syndrome carriers and their offspring. The model assumed similar age distribution of CRC across generations (i.e. that there was no true anticipation). Age distribution of CRC diagnosis, and lifetime fertility rates (grouped by age of diagnosis of CRC) were determined from the Australasian Colorectal Cancer Family Registry (ACCFR). Apparent anticipation was calculated by comparing ages of diagnosis of CRC in affected parent-child pairs. A total of 1,088 patients with CRC were identified from the ACCFR. Total lifetime (cohort) fertility was related to age of diagnosis of CRC (correlation coefficient 0.13, P = 0.0001). In the simulation, apparent anticipation was 1.8 ± 0.54 years (P = 0.0044). Observed apparent anticipation in the ACCFR cohort was 4.8 ± 1.73 years (P = 0.0064). There was no difference in apparent anticipation between the simulate d and observed parent-child pairs (P = 0.89). The appearance of genetic anticipation in Lynch syndrome can be falsely created due to changes in fertility.

  18. Fertility prognosis for infertile couples

    DEFF Research Database (Denmark)

    Bostofte, E; Bagger, P; Michael, A

    1993-01-01

    OBJECTIVE: To develop a fertility prognosis model for infertile couples. DESIGN: Prospective follow-up study. PARTICIPANTS: In the period November 30, 1977 to June 1, 1985, 321 consecutive couples were investigated for infertility at Hvidovre University Hospital. Investigation of the female...... MEASURE: The Cox regression model was used to predict the time required to conceive based on informations provided by fertility investigations. RESULTS: Three of 16 prognostic variables (the period of infertility, the female infertility factor, and the P-test) possess significant prognostic information...

  19. The nanophase iron mineral(s) in Mars soil

    Science.gov (United States)

    Banin, A.; Ben-Shlomo, T.; Margulies, L.; Blake, D. F.; Mancinelli, R. L.; Gehring, A. U.

    1993-01-01

    A series of surface-modified clays containing nanophase (np) iron oxide/oxyhydroxides of extremely small particle sizes, with total iron contents as high as found in Mars soil, were prepared by iron deposition on the clay surface from ferrous chloride solution. Comprehensive studies of the iron mineralogy in these "Mars-soil analogs" were conducted using chemical extractions, solubility analyses, pH and redox, x ray and electron diffractometry, electron microscopic imaging, specific surface area and particle size determinations, differential thermal analyses, magnetic properties characterization, spectral reflectance, and Viking biology simulation experiments. The clay matrix and the procedure used for synthesis produced nanophase iron oxides containing a certain proportion of divalent iron, which slowly converts to more stable, fully oxidized iron minerals. The clay acted as an effective matrix, both chemically and sterically, preventing the major part of the synthesized iron oxides from ripening, i.e., growing and developing larger crystals. The precipitated iron oxides appear as isodiametric or slightly elongated particles in the size range 1-10 nm, having large specific surface area. The noncrystalline nature of the iron compounds precipitated on the surface of the clay was verified by their complete extractability in oxalate. Lepidocrocite (gamma-FeOOH) was detected by selected area electron diffraction. It is formed from a double iron Fe(II)/Fe(III) hydroxy mineral such as "green rust," or ferrosic hydroxide. Magnetic measurements suggested that lepidocrocite converted to the more stable maghemite (gamma-Fe2O3) by mild heat treatment and then to nanophase hematite (alpha-Fe2O3) by extensive heat treatment. After mild heating, the iron-enriched clay became slightly magnetic, to the extent that it adheres to a hand-held magnet, as was observed with Mars soil. The chemical reactivity of the iron-enriched clays strongly resembles, and offers a plausible mechanism

  20. Soil Fertility Status on Organic Paddy Experiment

    Directory of Open Access Journals (Sweden)

    Mujiyo

    2015-07-01

    Full Text Available The study aims to determine fertility status of the soil after organic paddy experiments using kinds and doses of organic fertilizers. Experiment was conducted at greenhouse laboratory in Faculty of Agriculture Sebelas Maret University Surakarta. Experimental design used completely randomized design with 9 kinds of treatment was replicated 3 times. Experiments were the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations that are based on fulfilling nutrient requirements of 120 kg N ha-1. Result shows that the use of cow manure, Azolla fertilizers and Azolla inoculum had no effect on changes of soil fertility status. Soil fertility status was not significantly correlated with cow manure (0,16ns, Azolla fertilizer (0,26ns and Azolla inoculum (0,16ns. Average of final soil fertility status included fertile category, which was similar as the initial soil fertility status. Average of final soil properties of treatment but nevertheless was relatively higher than in no treatment, indicating the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations had greater impact to soil properties. Cow manure despite increased available K2O and dry grain, but it did not significantly increase the soil fertility status from fertile to very fertile. This was presumably due to the relatively short experiment period, only one planting season had not given significant effect to soil properties. Implication of this study is the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations although did not increase the soil fertility status but could maintain soil fertility status as the initial conditions before planting.